KR102450726B1 - Optical lens, light emitting module and light unit having thereof - Google Patents

Abstract

A light emitting module according to an embodiment includes: a light emitting device emitting light through an upper surface and a plurality of side surfaces; and an optical lens disposed on the light emitting element, the optical lens comprising: an inclined bottom surface; an incident surface having a recess on the light emitting element; a first light emitting surface emitting the light incident on the incident surface and having a curved surface; and a second light exit surface disposed around the lower periphery of the first light exit surface and having an aspherical surface, wherein a depth of the recess is 80% or more of a thickness of the optical lens, and a second light exit surface is passed through the incidence surface. The emission angle of the first light emitted to the light exit surface is smaller than the incidence angle of the incidence surface with respect to the optical axis, and the exit angle of the second light reflected by the bottom surface through the incidence surface and emitted to the second light exit surface is smaller than the incident angle of the incident surface with respect to the optical axis, the incident surface and the first light output surface have different centers of radii of curvature, and the centers of circles having different radii of curvature are horizontal to the vertices of the incident surface. It is disposed below one straight line, and a line segment between the vertex of the incident surface and the first edge of the incident surface with respect to the optical axis forms a first angle, the first angle being greater than the inclined angle of the bottom surface. .

Description

Optical lens, light emitting module, and light unit having the same

The present invention relates to an optical lens, a light emitting module, and a light unit having the same.

A light emitting device, for example, a light emitting diode (Light Emitting Device), is a kind of semiconductor device that converts electrical energy into light, and has been spotlighted as a next-generation light source by replacing conventional fluorescent lamps and incandescent lamps.

Since light emitting diodes generate light using semiconductor devices, they consume very low power compared to incandescent lamps that generate light by heating tungsten, or fluorescent lamps that generate light by colliding ultraviolet rays generated through high-voltage discharge onto phosphors. .

In addition, since the light emitting diode generates light by using the potential gap of the semiconductor device, it has a longer lifespan, faster response characteristics, and environment-friendly characteristics compared to a conventional light source.

Accordingly, many studies have been conducted to replace the existing light source with a light emitting diode, and the use of the light emitting diode as a light source for lighting devices such as various lamps, display devices, electric signs, and street lamps used indoors and outdoors is increasing.

An embodiment provides an optical lens having different light exit surfaces.

The embodiment provides an optical lens in which the vertices of the incident surface and the first light exit surface are convex in the same direction.

Embodiments provide an optical lens in which the apex of the incident surface is closer to the apex of the first light exit surface than to the light source.

An embodiment provides an optical lens having a spherical first light exit surface and an inclined aspherical second light exit surface around an incident surface.

An embodiment provides an optical lens having a slanted bottom surface disposed around a light emitting device.

An embodiment provides an optical lens for changing an emission angle of light incident from a light emitting device emitting light on at least five surfaces.

The embodiment provides a light emitting module capable of controlling the luminance distribution of light emitted from an optical lens.

The embodiment provides an optical lens and a light emitting module having the same, in which an emission angle of light emitted to a region deviating from a beam angle of light is smaller than an incident angle.

The embodiment provides a light emitting module in which an absorption layer is provided on a circuit board in a region where the amount of light reflected from an optical lens is maximum.

An optical lens according to an embodiment, a bottom surface; a recess convex from the bottom surface; an incident surface on which light is incident around the recess; a first light emitting surface emitting light incident on the incident surface and having a spherical surface; and a second light exit surface disposed around the lower outer periphery of the first light exit surface and having an aspherical surface, wherein the recess is at least 80% of a distance between the apex of the first light exit surface and the bottom surface having a depth, a region overlapping the recess in a vertical direction among the regions of the first light exit surface includes a curved surface convex in the same direction as the recess, the first light exit surface has different radii of curvature, The centers of circles having different radii of curvature are disposed below a straight line horizontal to the vertex of the recess, and the second light exit surface has an exit angle smaller than the incidence angle of the first light incident on the incidence surface, An angle between the vertex of the incident surface and a line segment connecting the first edge of the incident surface with respect to the axis has a first angle, and the bottom surface is inclined at a second angle with respect to a first axis direction orthogonal to the optical axis. , the first angle is greater than the second angle.

A light emitting module according to an embodiment includes: a light emitting device emitting light through an upper surface and a plurality of side surfaces; and an optical lens disposed on the light emitting element, the optical lens comprising: an inclined bottom surface; an incident surface having a recess on the light emitting element; a first light emitting surface emitting the light incident on the incident surface and having a curved surface; and a second light exit surface disposed around the lower periphery of the first light exit surface and having an aspherical surface, wherein a depth of the recess is 80% or more of a thickness of the optical lens, and a second light exit surface is passed through the incidence surface. The emission angle of the first light emitted to the light exit surface is smaller than the incidence angle of the incidence surface with respect to the optical axis, and the exit angle of the second light reflected by the bottom surface through the incidence surface and emitted to the second light exit surface is smaller than the incident angle of the incident surface with respect to the optical axis, the incident surface and the first light output surface have different centers of radii of curvature, and the centers of circles having different radii of curvature are horizontal to the vertices of the incident surface. It is disposed below one straight line, and a line segment between the vertex of the incident surface and the first edge of the incident surface with respect to the optical axis forms a first angle, the first angle being greater than the inclined angle of the bottom surface. .

The embodiment may improve the luminance distribution of the optical lens by controlling the light path emitted to the side of the light emitting device disposed under the optical lens.

The embodiment may reduce noise such as a hot spot caused by light extracted from an optical lens.

The embodiment may provide a wide gap between the light emitting elements by the optical lens, thereby reducing interference between the optical lenses.

In the embodiment, by disposing the absorption layer on the circuit board to absorb the light reflected by the spherical first light emitting surface, it is possible to control the luminance distribution.

The embodiment may reduce the number of light emitting devices disposed in the backlight unit.

The embodiment may improve the reliability of a light emitting module having an optical lens.

Embodiments may improve images by minimizing interference between adjacent optical lenses.

The embodiment may improve the reliability of a light unit such as an optical lens.

Embodiments may improve the reliability of a lighting system having a light emitting module.

1 is a side cross-sectional view of an optical lens according to an embodiment.
FIG. 2 is a side cross-sectional view of the light emitting module having the optical lens of FIG. 1 .
FIG. 3 is a view showing the centers of radii of curvature of the incident surface and the first light output surface of the optical lens of FIG. 1 .
FIG. 4 is a view showing light distribution of an incident surface and an exit surface of the optical lens of FIG. 1 .
FIG. 5 is a view for explaining an incident surface of the optical lens of FIG. 1 .
FIG. 6 is a view for explaining emission angles of first and second light exit surfaces of the optical lens of FIG. 1 .
FIG. 7 is a side view of the optical lens of FIG. 1 .
FIG. 8 is a bottom view of the optical lens of FIG. 1 .
FIG. 9 is a view for explaining a path of light reflected by a second light emitting surface in the optical lens of FIG. 1 .
FIG. 10 is a view showing another example of a bottom surface of the optical lens of FIG. 1 .
11 is a view showing another example of a second light emitting surface of the optical lens of FIG. 1 .
12 is an exemplary view of a light emitting module including an optical lens having a support protrusion and a circuit board having an absorption layer according to an embodiment.
13 is a perspective view of an optical lens of the light emitting module of FIG. 12 .
14 is a side cross-sectional view illustrating a light unit having an optical lens according to an embodiment.
15 is a diagram illustrating an example of defining a curved section of an incident surface of the optical lens of FIG. 1 using a Bezier curve function.
16 is a diagram illustrating an example of defining a curved section of a first light emitting surface of the optical lens of FIG. 1 using a Bezier curve function.
17 is a first example illustrating a detailed configuration of a light emitting device disposed on a circuit board according to an embodiment.
18 is a second example of a light emitting device disposed on a circuit board according to an embodiment.
19 is a diagram illustrating a third example of a light emitting device disposed on a circuit board according to an embodiment.
20 is a diagram illustrating a display device having a light emitting module according to an exemplary embodiment.
21 is a view showing the luminance distribution of Examples and Comparative Examples.
22 is a diagram illustrating a change in light emitted from an optical lens according to an embodiment.
23 is a graph showing the luminance distribution according to whether the second light exit surface is uneven in the optical lens according to the embodiment.
24 is a graph illustrating a color difference change according to whether a second light emitting surface is uneven in the optical lens according to the embodiment.
25 is a graph showing image uniformity according to whether or not an absorption layer of a circuit board exists in the optical lens according to the embodiment.

Hereinafter, the embodiments will be clearly revealed through the accompanying drawings and the description of the embodiments. In the description of the embodiments, each layer (film), region, pattern or structure is “on” or “under/under” the substrate, each layer (film), region, pad or pattern. In the case of being described as being “formed on,” “on” and “under/under” both refer to “directly” or “indirectly” formed through another layer. include In addition, the criteria for the upper / upper or lower / lower of each layer will be described with reference to the drawings.

Hereinafter, an optical lens and a light emitting module having the same according to an embodiment will be described with reference to the accompanying drawings.

1 is a side cross-sectional view of an optical lens according to an embodiment, and FIG. 2 is a side cross-sectional view of a light emitting module having the optical lens of FIG. 1 .

1 and 2 , the light emitting module 301 includes a light emitting device 100 , an optical lens 300 disposed on the light emitting device 100 , and a circuit disposed under the light emitting device 100 . and a substrate 400 .

The light emitting devices 100 may be arranged on the circuit board 400 with a predetermined interval therebetween. The light emitting device 100 is disposed between the optical lens 300 and the circuit board 400 , is driven by receiving power from the circuit board 400 , and emits light.

The light emitting device 100 emits light through an upper surface S1 and a plurality of side surfaces S2 as shown in FIG. 2 , and has, for example, five or more light emitting surfaces. The plurality of side surfaces S2 of the light emitting device 100 has a structure including at least four side surfaces, and may be a light emitting surface.

Since the light emitting device 100 provides five or more light emitting surfaces, the distribution of the beam angle may be widened by the light emitted through the side surface S2 . The light beam distribution angle distribution of the light emitting device 100 may be 140 degrees or more, for example, 142 degrees or more. The full width at half maximum of the directional angle distribution of the light emitting device 100 may be 70 degrees or more, for example, 71 degrees or more. The half width represents a width having a luminous intensity of 1/2 of the maximum luminous intensity of the beam angle. By providing a wide distribution of the beam angle of the light emitting device 100 , there is an effect that light diffusion using the optical lens 300 is easier.

The light emitting device 100 may include an LED chip including a compound semiconductor, for example, at least one of a UV (ultraviolet) LED chip, a blue LED chip, a green LED chip, a white LED chip, and a red LED chip. The light emitting device 100 may include at least one or both of a group II-VI compound semiconductor and a group III-V compound semiconductor. The light emitting device 100 may emit at least one of blue, green, blue, UV, and white light.

The optical lens 300 may change the path of light emitted from the light emitting device 100 and then extract it to the outside. The light emitting device 100 may be defined as a light source.

The optical lens 300 includes a bottom surface 310 , a recess 315 convex above the bottom surface 310 , an incident surface 320 around the recess 315 , and the bottom surface 310 and a first light exit surface 330 disposed on the opposite side of the incident surface 320 , and a second light exit surface 335 disposed around a lower portion of the first light exit surface 330 . do.

The optical lens 300 receives the light emitted from the light emitting device 100 to the incident surface 320 and emits it to the first and second light output surfaces 330 and 335 . Some light incident from the incident surface 320 may be emitted to the bottom surface 310 through a predetermined path.

When the light emitted from the light emitting device 100 has a directional angle distribution of 136 degrees or more and is incident on the incident surface 320 , the optical lens 300 diffuses it through the first and second light output surfaces 330 and 335 . can

Since the incident surface 320 of the optical lens 300 is disposed to face the plurality of side surfaces S2 of the light emitting device 100 , the light emitted from the side surface 320 of the light emitting device 100 is directly transmitted. can be hired Accordingly, the light emitted to the side surface S2 of the light emitting device 100 may be incident on the incident surface 320 without leakage.

A direction perpendicular to the upper surface of the light emitting device 100 may be referred to as an optical axis Y0 direction. The direction of the optical axis Y0 may be a direction orthogonal to the upper surface of the circuit board 400 . The direction of the first axis X0 perpendicular to the optical axis Y0 may be a direction perpendicular to the optical axis Y0 from the light emitting device 100 .

The recess 315 is recessed in the optical axis Y0 direction from the center region of the bottom surface 310 . The recess 315 may have a greater depth as it approaches the center region or the optical axis Y0. The width D1 of the recess 315 may gradually become narrower as it progresses in the optical axis Y0 direction (eg, upward direction). The recess 315 may be closer to the first light emitting surface 330 as it rises upward.

The cross-sectional shape of the side of the recess 315 may include a hemispherical shape or a semi-elliptical shape, and the lower shape of the surface may include a circular shape or a polygonal shape. The incident surface 320 is disposed around the convex recess 315 upward from the center region of the bottom surface 310 .

The incident surface 320 may be formed of a rotating body having a Bezier curve. The curve of the incident surface 320 may be implemented as a spline, for example, a cubic, B-spline, or T-spline. The curve of the incident surface 320 may be implemented as a Bezier curve.

The incident surface 320 is a surface of the recess 315 and may be disposed outside the upper surface S1 and the side surface S2 of the light emitting device 100 .

The bottom surface 310 of the optical lens 300 may include a flat surface, a curved surface, or a curved surface and a flat surface. The bottom surface 310 may provide a surface inclined with respect to the top surface of the circuit board 400 . The bottom surface 310 of the optical lens 300 may be provided as a surface inclined with respect to the first axis X0. 80% or more of the bottom surface 310 may be disposed to be inclined with respect to the top surface of the circuit board 400 . The bottom surface 310 may include a total reflection surface.

The bottom surface 310 of the optical lens 300 includes a first edge 23 and a second edge 25 . The first edge 23 is a boundary point between the incident surface 320 and the bottom surface 310 , and may be the bottom of the optical lens 300 . The first edge 23 may be the lowest point among the areas of the bottom surface 310 . The position of the first edge 23 may be lower than that of the second edge 25 based on a horizontal line. The first edge 23 may be a lower circumference of the incident surface 320 .

The second edge 25 may be disposed on the lower periphery of the second light emitting surface 335 or at the outermost portion of the bottom surface 310 . The second edge 25 may be a boundary point between the bottom surface 310 and the second light exit surface 335 .

The first edge 23 and the second edge 25 may be both ends of the bottom surface 310 . The bottom-view shape of the first edge 23 may be a circular shape or an elliptical shape, and the second edge 25 may have a bottom-view shape of a circular shape or an oval shape.

The top surface of the circuit board 400 may be disposed closer to the first edge 23 than the second edge 25 of the bottom surface 310 of the optical lens 300 . The first edge 23 of the bottom surface 310 may be in contact with the top surface of the circuit board 400 , and the second edge 25 is at a maximum distance T0 from the top surface of the circuit board 400 . can be spaced apart. The second edge 25 may be disposed at a lower position than the active layer in the light emitting device 100 , thereby preventing light loss.

The first and second light emitting surfaces 330 and 335 of the optical lens 300 refract and emit the incident light. The second light exit surface 335 refracts the extracted light after refraction with respect to the optical axis Y0 to be smaller than the angle of the incident light before refraction. Accordingly, it is possible to provide a long optical interference distance between adjacent optical lenses 300, and some light emitted through the second light exit surface 335 and the light emitted to the first light exit surface 330 are separated from the optical lens ( 300) may be mixed with each other.

The first light emitting surface 330 of the optical lens 300 may be formed as a spherical surface through which light is emitted to the entire area. The center region of the first light emitting surface 330 may be a vertex 31 or a peak, and includes a curved shape continuously connected from the apex 31 . The first light emitting surface 330 may reflect or refract incident light to be emitted to the outside. In the first light exit surface 330 , an emission angle after refraction of the light emitted to the first light exit surface 330 with respect to the optical axis Y0 may be greater than an incidence angle before refraction.

The monotony of the first light emitting surface 330 of the optical lens 300 increases according to the distance from the optical axis Y0 within the half value of the light beam distribution, and the second light emitting surface 335 is the It includes a region that deviates from the half-maximum angle of the directional angle distribution, and the monotony decreases according to a distance with respect to the optical axis Y0.

The first light emitting surface 330 may be formed of a rotating body having a Bezier curve. The curve of the first light emitting surface 330 may be implemented as a spline, for example, a cubic, B-spline, or T-spline. The curve of the first light emitting surface 330 may be implemented as a Bezier curve. The optical lens 300 may be provided in a rotationally symmetrical shape with respect to the optical axis Y0.

The center region of the first light emitting surface 330 is adjacent to the optical axis Y0, and may be a curved surface convex in an upward direction or a flat surface. A region between the center region of the first light emitting surface 330 and the second light emitting surface 335 may be provided in a convex curved shape.

The incident surface 320 and the first light exit surface 330 may have positive radii of curvature. The center area and the peripheral area of the first light emitting surface 330 may not have a negative radius of curvature but may have different positive radii of curvature. The center area of the first light emitting surface 330 may include an area in which a radius of curvature is 0.

A radius of curvature of the incident surface 320 may be smaller than a radius of curvature of the first light exit surface 330 . Alternatively, the inclination of the incident surface 320 may be greater than that of the first light emitting surface 330 .

The second light exit surface 335 is disposed around the lower portion of the first light exit surface 330 to refract and emit the incident light. The second light emitting surface 335 has an aspherical shape or a flat surface. The second light exit surface 335 may be, for example, a surface perpendicular to the top surface of the circuit board 400 or an inclined surface. When the second light emitting surface 335 is formed as an inclined surface, there is an effect of easy separation during injection molding.

The second light emitting surface 335 may be disposed at the outermost side of the optical lens 300 . The second light exit surface 335 may extend as a flat surface around a lower portion of the first light exit surface 330 . The second light exit surface 335 may include a third edge 35 adjacent to the first light exit surface 330 . The second edge 25 may be a lower edge of the second light exit surface 335 , and the third edge 35 may be an upper edge of the second light exit surface 335 or the first and second light exit surfaces. It may be a boundary point between (330,335).

The second light emitting surface 335 receives and refracts some light emitted to the side surface S2 of the light emitting device 100 to be extracted. In this case, in the second light exit surface 335 , an exit angle of the emitted light with respect to the optical axis Y0 may be smaller than an incidence angle before refraction. Accordingly, it is possible to provide a long optical interference distance between adjacent optical lenses 300 .

Referring to FIG. 1 , the optical lens 300 may be disposed to have a width D4 wider than a thickness D3 . The width D4 may be 2.5 times or more, for example, 3 times or more of the thickness D3. The width D4 of the optical lens 300 may be 15 mm or more. Since the width D4 of the optical lens 300 is wider than the thickness D3 in the above range, it is possible to provide a uniform luminance distribution over the entire area of the light unit, for example, the backlight unit, and also the thickness of the light unit. can reduce

Here, the lower width D1 of the incident surface 320 of the optical lens 300 may be the lower width of the recess 315 and may be disposed wider than the width W1 of the light emitting device 100 . . The incident surface 320 and the recess 315 have a size through which the light emitted from the light emitting device 100 can be easily incident.

A depth D2 of the recess 315 may be equal to or deeper than a lower width D1 of the incident surface 320 . The depth D2 of the recess 315 may have a depth of 75% or more, for example, 80% or more of the thickness D3 of the optical lens 300 . The depth D2 of the recess 315 may be 80% or more of the distance between the apex 31 of the first light exit surface 330 and the bottom surface 310 or the first edge 23 . Since the depth D2 of the recess 315 is deep, even if the center area of the first light exit surface 330 does not have a total reflection surface or a negative curvature, the apex 21 of the incidence surface 320 is The light may be diffused in the lateral direction even in an adjacent area. The depth D2 of the recess 315 is the depth of the apex 21 of the incident surface 320 , and the depth of the apex 21 of the incident surface 320 is deep, so that the apex 21 and its The light incident on the peripheral area may be laterally refracted.

A ratio (D1:W1) of the lower width D1 of the incident surface 320 to the width W1 of the light emitting device 100 may be in a range of 1.8:1 to 3.0:1. When the lower width D1 of the incident surface 320 is less than three times the width W1 of the light emitting element 100, the light emitted from the light emitting element 100 hits the incident surface 320 can be entered effectively.

A position having the same width as that of the light emitting device 100 among the incident surface 320 may be spaced apart from the vertex 21 of the incident surface 320 by a predetermined distance D6 . The distance D6 may be the same as the minimum distance D5 between the recess 315 and the first light emitting surface 330 or may have a difference within 0.1 mm. This may guide the light emitted through the upper surface S1 of the light emitting device 100 to be incident in the form of a surface light source up to the periphery of the apex 21 of the incident surface 320 .

A distance D8 from a position having the same width as that of the light emitting device 100 among the incident surface 320 to the apex 31 of the first light emitting surface 330 is in the range of 0.5 mm to 2 mm, and the distance D5 ) or twice the distance D6. This is because the area of the incident surface 320 having the same width as that of the light emitting device 100 is positioned at a distance of 2 mm or less from the apex 31 of the first light exit surface 330, so that the first light exit surface ( Even if the center area of 330 does not have a negative radius of curvature, light may be diffused in the lateral direction by the distance between the depth D2 of the incident surface 310 and the vertex 31 .

The distance D6 between the apex 21 of the recess 315 and the width W1 in the recess 315 is the apex 21 of the recess 315 and the first light exit surface. The ratio of the distance D5 between the vertices 31 of 330 satisfies the range of 0.5:1 to 1:1.

The minimum distance D5 between the recess 315 and the first light exit surface 330 is between the apex 21 of the recess 315 and the apex 31 of the first light exit surface 330 . may be an interval of The distance D5 may be, for example, 1.5 mm or less, for example, may be in the range of 0.6 mm to 1 mm. When the distance D5 between the apex 21 of the recess 315 and the apex 31 of the first light exit surface 330 is 1.5 mm or more, it proceeds to the center region of the first light exit surface 330 Since the amount of light may be increased, a hot spot phenomenon may occur. When the distance D5 between the apex 21 of the recess 315 and the second light exit surface 31 is less than 0.6 mm, there is a problem in that the center-side rigidity of the optical lens 300 is weakened. By disposing the distance D5 between the recess 315 and the first light exit surface 330 in the above range, even if the center region of the second light exit surface 335 does not have a total reflection surface or a negative curvature , it is possible to spread the light path in the horizontal direction to the periphery of the center region. This means that as the apex 21 of the recess 35 is adjacent to the convex apex 31 of the first light emitting surface 330, the lateral direction of the first light emitting surface 330 through the incident surface 320 is increased. The amount of propagating light may be increased. Accordingly, it is possible to increase the amount of light diffused in the lateral direction of the optical lens 300 .

The apex 21 of the recess 315 is a vertex 31 that is the center of the first light emitting surface 330 rather than a straight line extending horizontally from the third edge 35 of the second light emitting surface 335 . may be placed closer to the

Referring to FIG. 3 , in the optical lens 300 , the first light emitting surface 330 may have a plurality of circle components having different radii of curvature ra, rb, and rc, and The centers Pa, Pb, and Pc may be disposed at different positions. The centers Pa, Pb, and Pc of the circle components of the first light emitting surface 330 may be disposed below a horizontal straight line of the vertex 21 of the incident surface 320 . The centers Pa, Pb, and Pc of the original components of the first light emitting surface 330 may be disposed in an area overlapping the optical lens 300 in a vertical direction.

The incident surface 320 may have a plurality of circle components having different radii of curvature, and the center of the circle component may be disposed below a horizontal straight line of the vertex 21 of the incident surface 320 , , may be disposed in an area overlapping the optical lens 300 in a vertical direction.

Referring to FIG. 4 , looking at the optical path of the optical lens 300 , the first point P1 of the light emitted from the light emitting device 100 is incident on the incident surface 320 of the optical lens 300 . One light L1 may be refracted and emitted to a predetermined second point P2 of the first light emitting surface 330 . In addition, among the light emitted from the light emitting device 100 , the second light L2 incident on the third point P3 of the incident surface 320 is a predetermined fourth point ( P4) can be released.

Here, an incident angle of the first light L1 incident on the first point P1 of the incident surface 320 with respect to the optical axis Y0 is defined as a first angle θ1, and the optical axis Y0 is defined as the first angle θ1. An emission angle of the first light L1 emitted to an arbitrary third point P2 of the first light exit surface 330 may be defined as a second angle θ2 based on . An incident angle of the second light L2 incident on the third point P3 of the incident surface 320 with respect to the optical axis Y0 is defined as a third angle θ3, and the optical axis Y0 is defined as a reference Thus, an emission angle of the second light L2 emitted to the fourth point P4 of the second light exit surface 335 may be defined as a fourth angle θ4. The second light L2 may be light emitted from a side surface of the light emitting device 100 .

The second angle θ2 is greater than the first angle θ1 . The second angle θ2 gradually increases as the first angle θ1 gradually increases, and gradually decreases as the first angle θ1 decreases as the first angle θ1 decreases. In addition, the first and second angles θ1 and θ2 satisfy the condition of θ2>θ1 or 1<(θ2/θ1). The second angle θ2 of the first light emitting surface 330 is an emission angle after refraction, and may be greater than an incidence angle before refraction. Accordingly, the first light emitting surface 330 refracts the first light L1 that travels to the first light emitting surface 330 among the light incident through the incident surface 320, so that the first light ( L1) may be diffused in the lateral direction of the optical lens 300 .

The fourth angle θ4 may be smaller than the third angle θ3 . As the third angle θ3 increases, the fourth angle θ4 increases, and as the third angle θ3 decreases, the fourth angle θ4 decreases. In addition, the third and fourth angles θ3 and θ4 satisfy the condition of θ4<θ3 or 1>(θ4/θ3). The fourth angle θ4 of the second light exit surface 335 is an emission angle after refraction, and may be smaller than an incidence angle before refraction. Light emitted through the side surface S2 of the light emitting device 100 or light having a deviation from a light beam angle may be incident on the second light exit surface 335 . Accordingly, the second light emitting surface 335 refracts the light emitted through the side surface S2 of the light emitting device 100 and the light outside the light directivity angle distribution so as to proceed within the half value region of the luminance distribution. can Light loss may be reduced by the second light emitting surface 335 .

The third edge 35 of the second light emitting surface 335 is disposed above the position of the half-value, for example, the fourth angle θ4 of the distribution angle of the light emitting device 100 with respect to the optical axis Y0. can be For example, the angle between the optical axis Y0 and the straight line connecting the reference point P0 to the third edge 35 may be smaller than the half-maximum angle of the light emitting device 100 .

Among the light emitted from the light emitting device 100 , the light irradiated to the region adjacent to the half-value angle may be controlled to be emitted through the second light emitting surface 335 . In this case, the second light L2 emitted to the second light exit surface 335 may be mixed with lights traveling to the first light exit surface 330 .

Here, the reference point P0 may be an intersection of the optical axis Y0 and the light emitting device 100 . The reference point P0 may be disposed at a position lower than the upper surface S1 of the light emitting device 100 . The reference point P0 of the light emitting device 100 is a point at which the center of the upper surface S1 and the centers of the plurality of side surfaces S2 intersect, or the center of the upper surface S1 and the lower center of each side surface S2 intersect. It can be a point to be The reference point P0 may be an intersection point at which the optical axis Y0 and the light emitted from the light emitting device 100 intersect. The reference point P0 may be disposed on the same horizontal line as the bottom point of the optical lens 300 or disposed at a higher position.

Among the light emitted from the light emitting device 100 , the light L3 incident on the fifth point P5 of the incident surface 320 is reflected by the bottom surface 310 of the optical lens 300 and the second light It may be transmitted or reflected through the sixth point P6 of the exit surface 335 . In this case, the second light exit surface 335 transmits or reflects light at an exit angle θ9 smaller than an incidence angle θ8 of the light reflected from the bottom surface 310 . The incident angle θ8 and the exit angle θ9 are angles with respect to the optical axis Y0. Here, the light reflected by the bottom surface 310 and traveling to the second light exit surface 335 is refracted at an exit angle θ8 smaller than the incidence angle θ8, so that the side surface S2 of the light emitting device 100 . It is possible to effectively reuse the light that can be leaked through. In addition, there is an effect of preventing light leakage through total reflection by the bottom surface 310 even for light that deviates from the half-maximum angle in the light directivity angle distribution of the light emitting device 100 .

22 is a diagram illustrating a ratio of an exit angle emitted to the first and second light exit surfaces to an incident angle of the incident surface. As shown in FIG. 22 , the area A1 of the first light exit surface 330 gradually decreases as the ratio of the exit angle/incident angle is adjacent to the area A2 of the second light exit surface 335, and is larger than 1. have a proportion. The X-axis direction of FIG. 22 represents the beam angle, and the distribution of the beam beam angle of 68 degrees or more may be controlled by the area A2 of the second light exit surface 335 .

It has a value less than 1 in the area A2 of the second light exit surface 335 , and the amount of light emitted through the area A3 reflected by the bottom surface 310 to the second light exit surface 335 . The ratio of the exit angle/incident angle has a value smaller than that of the area A2.

Among the light emitted to the side surface S2 of the light emitting device 100 , the light emitted through the second light exit surface 335 is emitted at an emission angle smaller than the incident angle, and thus the distance between the optical lenses 100 as shown in FIG. 14 . (G1) That is, the optical interference distance can be increased. In addition, since the luminance distribution by the optical lens 300 is improved, the distance H1 between the circuit board 400 and the optical sheet 514 may be reduced. In addition, the number of optical lenses 300 disposed in the backlight unit may be reduced.

5, the position of the first edge 23 of the bottom surface 310 in the optical lens 300 may be lower than or located at the same position as the reference point P0 of the light emitting device 300, The position of the second edge 25 may be higher than the upper surface S1 of the light emitting device 100 , but is not limited thereto. Accordingly, the bottom surface 310 totally reflects the light emitted through the side surface S2 of the light emitting device 100 incident from the incident surface 320 .

The optical lens 300 has a reference point P0, a vertex 21 of the incident surface 320, and a line segment connecting the first edge 23 of the incident surface 320 in a triangular shape, for example, in a right-angled triangular shape. can be provided. The angle θ11 between the reference point P0 of the optical axis Y0 and the line segment connecting the vertex 21 and the first edge 23 may be 30 degrees or less, for example, 20 degrees to 24 degrees. This angle θ12 may be 1/3 or less of the other angle θ14.

1 and 5 , the center region of the first light exit surface 330 overlapping the recess 315 in the vertical direction is treated as a flat surface or a convex surface, so that the depth of the recess 315 ( When D2 of FIG. 1 ) is low, a hot spot may be generated by the light transmitted to the center region of the first light emitting surface 330 . In the embodiment, the depth D2 of the recess 315 is disposed adjacent to the convex center region of the first light exit surface 330 to measure the light by the incidence surface 320 of the recess 315 . direction can be deflected. Accordingly, a hot spot caused by the light emitted by the first light emitting surface 330 of the optical lens 300 may be reduced.

An angle θ13 between the optical axis Y0 of the reference point P0 and the vertex 31 and the first edge 23 may be in the range of 15 degrees to 22 degrees smaller than the angle θ11. Here, the angle θ11/θ12 < 1 is satisfied, and the angle θ11/θ5 > 1 is satisfied. Here, the angle θ5 is an inclined angle of the bottom surface 310 . The angle θ11 has a range of 4 times or more, for example, 5 times or more and 20 times or less than the angle θ5.

Referring to FIG. 6 , the inclined angle θ5 of the bottom surface 310 of the optical lens 300 may be within 5 degrees, for example, in the range of 0.5 degrees to 4 degrees. The angle θ6 between the first straight line X1 connecting both edges 23 and 25 of the bottom surface 310 and the optical axis Y0 may be an acute angle, for example, 89.5 degrees or less, for example, 87 degrees or less. . As the bottom surface 310 is disposed as a surface having an inclined angle θ5, the light incident through the side surface S2 of the light emitting device 100 is reflected and transmitted through the second light exit surface 335 or reflect it The emission angle of the second light exit surface 335 is smaller than the incidence angle incident through the reflection surface 310 , thereby reducing interference between adjacent optical lenses. Accordingly, the amount of light emitted through the second light emitting surface 335 of the optical lens 300 may be improved.

The inclined angle θ5 of the bottom surface 310 may be greater than the inclined angle θ7 of the second light emitting surface 335 illustrated in FIG. 11 .

In addition, the linear distance between the second edge 25 and the third edge 35 from the bottom surface 310 may be smaller than the depth D2 of the recess 315 . The width D7 of the second light exit surface 335 may be 1.5 times or more, for example, 2 times or more of the distance between the recess 315 and the first light exit surface 330 . The angle between the straight line connecting the third edge 35 of the second light emitting surface 335 and the reference point P0 and the optical axis Y0 is a half-maximum angle of the directional angle distribution of the light emitting device 100, for example, an angle. It may be smaller than (θ4). Here, the half-maximum angle represents an angle at which the light output emitted from the light emitting device 100 becomes 50% or 1/2 of the peak value with respect to the optical axis.

In the region of the second light exit surface 335 , when the exit angle θ2 from which the second point P2 is emitted is 1/2 of the half-maximum angle distribution of the light emitting device 100 , the second point P2 is The distance D11 between the point of the incident surface 320 of the light incident to the two points P2 and the optical axis Y0 may be less than 1/2 of the point D1. Even if the thickness of the optical lens 300 is reduced or the height of the apex of the first light emitting surface 330 is lowered, light may be diffused in the lateral direction.

A sixth angle θ6 between the line segment connecting the first edge 23 of the bottom surface 310 of the optical lens 300 with respect to the optical axis Y0 is the line segment and the second light exit surface 335 . It may be smaller than the angle θ61 between them. The angle θ6/θ61 < 1 may be satisfied. Here, the angle θ6 may be less than 90 degrees, and the angle θ61 may be 90 degrees or more, for example, 90 < θ61 ≤ 95 degrees. Since the line segment of the bottom surface 310 of the optical lens 300 has an acute angle with respect to the optical axis Y0 and an obtuse angle with respect to the second light exit surface 335, the light emitted from the light emitting device 100 is It is possible to provide total reflection, and also, by refracting the all-reflected light through the second light exit surface 335 , interference with other optical lenses can be reduced.

Meanwhile, the optical lens 300 includes one or a plurality of support protrusions (not shown) disposed below. The support protrusion protrudes downward from the bottom surface 310 of the optical lens 300 , that is, in the circuit board 400 direction. A plurality of the support protrusions are fixed on the circuit board 400 , and it is possible to prevent the optical lens 300 from being tilted.

As shown in FIG. 2 , the circuit board 400 may be arranged in a light unit such as a display device, a terminal, and a lighting device. The circuit board 400 may include a circuit layer electrically connected to the light emitting device 100 . The circuit board 400 may include at least one of a resin PCB, a metal core PCB (MCPCB, metal core PCB), and a flexible PCB (FPCB, flexible PCB), but is not limited thereto.

7 and 8 are views showing a side view and a rear view of an optical lens according to an embodiment.

Referring to FIG. 7 , the optical lens 300 may have a concave-convex surface on the second light emitting surface 335 . The uneven surface may be formed as a haze surface having a rough surface. The uneven surface may be a surface on which scattering particles are formed.

Referring to FIG. 8 , the bottom surface 310 of the optical lens 300 may have an uneven surface. The uneven surface may be formed as a haze surface having a rough surface, or scattering particles may be formed.

Referring to FIG. 23 , Example 1 shows the change in luminance distribution in an optical lens in which haze is not applied to the bottom and side surfaces, and Example 2 is the luminance distribution in the optical lens in which haze is applied to the bottom and side surfaces of the optical lens. indicates change. Here, it can be seen that the uniformity is improved in Example 2 in which haze is applied to the side and bottom surfaces of the optical lens.

Referring to FIG. 24 , Example 1 shows a change in color difference in an optical lens to which haze is not treated, and Example 2 shows a change in color difference in an optical lens in which haze is treated. It can be seen that in Example 2 in which the haze was treated, there was an effect of improving the color difference.

As shown in FIG. 9 , when uneven surfaces are formed on the second light exit surface 335 and the bottom surface 310 of the optical lens 300 , the light incident on the incidence surface 320 is transmitted to the bottom surface 310 . can be fully reflected. The second light emitting surface 335 may reflect some incident light, and the reflected partial light may be re-entered and refracted by the incident surface 320 or may be directly incident on the first light emitting surface 330 . have. Here, the amount of light incident on the incident surface 320 among the light reflected by the second light exit surface 335 may be greater than the amount of light incident on the first light exit surface 330 . The light re-incident to the incident surface 320 may be refracted and emitted through the first light exit surface 330 or the second light exit surface 335 .

Here, as shown in FIGS. 9 and 10 , the bottom surface 310 of the optical lens 300 includes a first area D9 having a curved surface and a second area D10 having a flat surface. The bottom surface 310 has a curved surface in an area adjacent to the recess 315 and a flat surface in an area adjacent to the second light exit surface 335 , and may be provided as a horizontal surface or an inclined surface.

The first region D9 has a radius of curvature convex upward from the first edge 23 . That is, the curved surface of the first region D9 on the bottom surface 310 is concave upward with respect to the horizontal extension line, and has, for example, a radius of curvature in the range of 65 mm to 75 mm. That is, the first region D9 may have a negative (-) curvature. The second region D10 is disposed between the first region D9 and the second edge 25 . A width of the first region D9 may be wider than a width of the second region D10 . The length ratio of the first region D9 and the second region D10 may be in a ratio of 6:4 to 9:1. As the width of the first region D7 increases, a hot spot phenomenon in the center of the optical lens 300 may be reduced.

Of the bottom surface 310 , a first area D9 which is a curved section is disposed adjacent to the incident surface 320 , and a second area D10 which is a flat section is disposed adjacent to the second edge 25 . can be The curved surface and the flat surface may be disposed above a line segment connecting the first edge 23 to the second edge 25 in a straight line. The first area D9 may be disposed lower than the horizontal extension line of the second edge 25 , and the second area D10 may be disposed on the same line as the horizontal extension line of the second edge 25 .

The first region D9 of the bottom surface 310 refracts the light emitted from the light emitting device 100 in different directions, thereby changing the luminance distribution by the first and second light emitting surfaces 330 and 335 . can give Such a luminance distribution of light may be improved when the bottom surface 310 includes a curved area, compared to an optical lens having an inclined surface in which a hot spot phenomenon in the center is inclined.

11 is another example of an optical lens according to an embodiment.

Referring to FIG. 11 , the second light emitting surface 335 of the optical lens may be inclined at a seventh angle θ7 with respect to the vertical optical axis Y0. The seventh angle θ7 may be smaller than the fifth angle θ5 . The angle θ7/θ5 <1 may be satisfied.

12 and 13 are structures in which an absorption layer is disposed on a circuit board in a light emitting module according to an embodiment.

12 and 13 , absorption layers 412 and 414 are disposed on the circuit board 400 . A portion L5 of the light incident on the first light emitting surface 330 of the optical lens 300 is transmitted and a portion L6 of the light is reflected. The absorption layers 412 and 414 absorb the incident light L6. The absorption layers 412 and 414 may include a black resist material.

The absorption layers 412 and 414 may be disposed in a region overlapping the optical lens 300 in a vertical direction. The absorption layers 412 and 414 may be disposed in a region that vertically overlaps with the bottom surface 310 of the optical lens 300 . The absorption layers 412 and 414 may be disposed on opposite sides of the circuit board 400 with respect to the recess 315 of the optical lens 300 .

When the width D4 of the optical lens 300 is wider than the width D13 of the circuit board 400 , the recess 315 of the optical lens 300 along the direction in which the optical lens 300 is arranged. ), the absorption layers 412 and 414 may be disposed on both sides, respectively. The absorption layers 412 and 414 absorb some light L6 reflected to the first light exit surface 330 of the optical lens 300 when incident.

Regions of the absorption layers 412 and 414 may be disposed under regions in which the amount of light reflected by the first light emitting surface 330 is maximum. Regions of the absorption layers 412 and 414 may be disposed to have the same radius D12 from the reference point of the optical axis Y0.

As shown in FIG. 25 , it can be seen that the case in which the absorbing layer is provided on the circuit board (Example 3) absorbs unnecessary light compared to the case in which the absorbing layer is not provided (Example 4), so that the light uniformity is improved.

12 and 13 , a plurality of support protrusions 350 and 355 may be disposed on the bottom surface 310 of the optical lens 300 . The plurality of support protrusions 350 and 355 include a first support protrusion 350 and a second support protrusion 355 . A plurality of the first support protrusions 350 may be disposed except for regions of the absorption layers 412 and 414 , and may be in contact with the upper surface of the circuit board 400 . Two or three or more of the first support protrusions 350 are arranged to support the optical lens 300 on the circuit board 400 .

The second support protrusion 355 may protrude higher than the height of the first support protrusion 350 . A distance between the second support protrusions 355 may be equal to or more spaced apart from the width D13 of the circuit board 400 . The circuit board 400 may be sandwiched between the second support protrusions 355 . Accordingly, the second support protrusion 355 is coupled to the outside of the circuit board 400 in the process of coupling the optical lens 300 to prevent the optical lens 300 from being tilted. Two or three or more of the second support protrusions 355 may be disposed and may be in contact with both sides of the circuit board 400 . A radius of the second support protrusion 355 may be greater than a radius of the first support protrusion 350 .

14 is a side cross-sectional view illustrating a light unit having an optical lens according to an embodiment.

Referring to FIG. 14 , the spacing G1 between the optical lenses 300 disposed in each circuit board 400 may be arranged to be narrower than the spacing between the optical lenses 300 disposed in different circuit boards 400 . The gap G1 may be arranged in a range of 6 to 10 times, for example, 7 to 9 times the width D4 of the optical lens 300 shown in FIG. 13 . The distance G1 between the optical lenses 300 may prevent optical interference between adjacent optical lenses 300 .

Here, the width D4 of the optical lens 300 may be 15 mm or more, for example, may be in the range of 16 mm to 20 mm. When the width D4 of the optical lens 300 is narrower than the above range, the number of optical lenses in the light unit may be increased, and a dark portion may be generated in a region between the optical lenses 300 . When the width D4 of the optical lens 300 is wider than the above range, the number of optical lenses in the light unit is reduced, but the luminance of each optical lens may be reduced.

21 is a diagram showing the luminance distribution of the optical lens in the light unit, and the embodiment has almost the same luminance distribution compared to the optical lens of the comparative example in which the emitting surface has a negative radius of curvature.

Meanwhile, in the optical lens 300, when the cross-sections of the incident surface 320 and the first light emitting surface 330 include a curved section, the curved section can satisfy a spline curve, which is a nonlinear numerical analysis technique. have. A spline curve is a function for making a smooth curve with a small number of control points. It can be defined as an interpolation curve passing through the selected control points and an approximation curve to the shape of a line connecting the selected control points. have. As the spline curve, a B-Spline curve, a Bezier curve, a Non-UniformRational B-Spline, NURBS curve, a cubic spline curve, etc. may be used.

For example, the curved section included in the cross section of each surface may be expressed through a Bezier curve equation. The Bezier curve function may be implemented as a function to obtain various free curves by moving a start point, which is the first control point, an end point, which is the last control point, and an internal control point located therebetween.

15 shows a curve of the incident surface of the recess, which may be implemented by moving a start point C1, an end point C2, and at least one internal control point C3.

By giving weights to the start point C1 and the end point C2 connected to the internal control point C3, the curve of the incident surface 320 can be obtained as shown in Table 1 below. Table 1 is the parameters for obtaining the curved section of the incident surface.

starting point endpoint Y (optical axis) 0.00 1.58 X (horizontal axis) 4.50-4.70 0.0099 Tangent Angle 109-113 -3.74 Tangent Length 1.43 0.45 Weight 0.48-0.50 0.71

The X-axis point and the weight of the starting point C1 may be changed according to the distance between the optical lens 300 and the optical sheet.

16 shows a curve of the first light emitting surface of the optical lens, which may be implemented by moving a start point C4 and an end point C5, and at least two internal control points C6 and C7.

By giving weights to the start point C4 and the end point C5 connected to the internal control points C6 and C7, the curve of the first light emitting surface 330 is obtained as shown in Table 2 below. can Table 2 shows parameters for obtaining a curved section of the first light emitting surface.

starting point endpoint Y (optical axis) 8.51 0.00 X (horizontal axis) 2.48 5.65-5.76 Tangent Angle -22 90 Tangent Length 1.42.363 4.80 Weight 0.44-0.48 0.52-0.54

The X-axis point and the weight of the starting point C4 may be changed according to the distance between the optical lens 300 and the optical sheet.

17 is a view showing a first example of the light emitting device 100 according to the embodiment. The light emitting device 100 and the circuit board 400 will be described with reference to FIG. 17 .

Referring to FIG. 17 , the light emitting device 100 includes a light emitting chip 100A. The light emitting device 100 may include a light emitting chip 100A and a phosphor layer 150 disposed on the light emitting chip 100A. The phosphor layer 150 includes at least one or a plurality of blue, green, yellow, and red phosphors, and may be disposed in a single layer or in multiple layers. In the phosphor layer 150, a phosphor is added in a light-transmitting resin material. The light-transmitting resin material may include a material such as silicone or epoxy, and the phosphor may be selectively formed from among YAG, TAG, Silicate, Nitride, and Oxy-nitride-based materials.

The phosphor layer 150 may be disposed on the upper surface of the light emitting chip 100A, or may be disposed on the upper surface and side surfaces of the light emitting chip 100A. The phosphor layer 150 may be disposed on a region where light is emitted from the surface of the light emitting chip 100A, and may convert a wavelength of light.

The phosphor layer 150 may include a single layer or different phosphor layers. In the different phosphor layers, the first layer may include at least one type of red, yellow, and green phosphor, and the second layer may include phosphor layers. It is formed on the first layer and may have a phosphor different from that of the first layer among red, yellow, and green phosphors. As another example, the different phosphor layers may include three or more phosphor layers, but is not limited thereto.

As another example, the phosphor layer 150 may include a film type. Since the film-type phosphor layer provides a uniform thickness, color distribution according to wavelength conversion may be uniform.

When describing the light emitting chip 100A, the light emitting chip 100A includes a substrate 111 , a first semiconductor layer 113 , a light emitting structure 120 , an electrode layer 131 , an insulating layer 133 , and a first It may include an electrode 135 , a second electrode 137 , a first connection electrode 141 , a second connection electrode 143 , and a support layer 140 .

The substrate 111 may use a light-transmitting, insulating or conductive substrate, for example, sapphire (Al ₂ O ₃ ), SiC, Si, GaAs, GaN, ZnO, Si, GaP, InP, Ge, Ga ₂ O ₃ At least one is available. A plurality of convex portions (not shown) may be formed on at least one or both of the top surface and the bottom surface of the substrate 111 to improve light extraction efficiency. A side cross-sectional shape of each convex portion may include at least one of a hemispherical shape, a semi-elliptical shape, and a polygonal shape. Here, the substrate 111 may be removed from the light emitting chip 100A. In this case, the first semiconductor layer 113 or the first conductive semiconductor layer 115 serves as a top layer of the light emitting chip 100A. can be placed.

A first semiconductor layer 113 may be formed under the substrate 111 . The first semiconductor layer 113 may be formed using a compound semiconductor of a group II to group V element. The first semiconductor layer 113 may be formed of at least one layer or a plurality of layers using a compound semiconductor of a group II to group V element. The first semiconductor layer 113 is, for example, a semiconductor layer using a compound semiconductor of a group III-V element, for example, GaN, InN, AlN, InGaN, AlGaN, InAlGaN, AlInN, AlGaAs, GaP, GaAs, GaAsP, AlGaInP, It may include at least one of GaP. The first semiconductor layer 113 has a composition formula of In _x Al _y Ga _1-xy N (0≤x≤1, 0≤y≤1, 0≤x+y≤1), and a buffer layer and undoped ) may be formed of at least one of the semiconductor layers. The buffer layer may reduce a difference in lattice constant between the substrate and the nitride semiconductor layer, and the undoped semiconductor layer may improve crystal quality of a semiconductor. Here, the first semiconductor layer 113 may not be formed.

A light emitting structure 120 may be formed under the first semiconductor layer 113 . The light emitting structure 120 is selectively formed from compound semiconductors of Group II to Group V elements and Group III-V elements, and may emit light at a predetermined peak wavelength within a wavelength range from an ultraviolet band to a visible light band.

The light emitting structure 120 includes a first conductivity type semiconductor layer 115 , a second conductivity type semiconductor layer 119 , and between the first conductivity type semiconductor layer 115 and the second conductivity type semiconductor layer 119 . It includes the formed active layer 117 , and another semiconductor layer may be further disposed on at least one of the top and bottom of each of the layers 115 , 117 , and 119 , but is not limited thereto.

The first conductivity type semiconductor layer 115 is disposed under the first semiconductor layer 113 and may be implemented as a semiconductor doped with a first conductivity type dopant, for example, an n-type semiconductor layer. The first conductivity type semiconductor layer 115 includes a compositional formula of In _x Al _y Ga _1-xy N (0≤x≤1, 0≤y≤1, 0≤x+y≤1). The first conductive semiconductor layer 115 may be selected from a group III-V group element compound semiconductor, for example, GaN, AlN, AlGaN, InGaN, InN, InAlGaN, AlInN, AlGaAs, GaP, GaAs, GaAsP, and AlGaInP. . The first conductivity-type dopant is an n-type dopant and includes a dopant such as Si, Ge, Sn, Se, Te, or the like.

The active layer 117 is disposed under the first conductivity type semiconductor layer 115 and selectively includes a single quantum well, a multiple quantum well (MQW), a quantum wire structure, or a quantum dot structure. and includes the cycle of the well layer and the barrier layer. The period of the well layer/barrier layer is, for example, InGaN/GaN, GaN/AlGaN, AlGaN/AlGaN, InGaN/AlGaN, InGaN/InGaN, AlGaAs/GaA, InGaAs/GaAs, InGaP/GaP, AlInGaP/InGaP, InP/GaAs at least one of the pairs of

The second conductive semiconductor layer 119 is disposed under the active layer 117 . The second conductivity type semiconductor layer 119 is a semiconductor doped with a second conductivity type dopant, for example, In _x Al _y Ga _1-xy N (0≤x≤1, 0≤y≤1, 0≤x+y≤ 1) contains the composition formula. The second conductive semiconductor layer 119 may be formed of at least one of compound semiconductors such as GaN, InN, AlN, InGaN, AlGaN, InAlGaN, AlInN, AlGaAs, GaP, GaAs, GaAsP, and AlGaInP. The second conductivity-type semiconductor layer 119 is a p-type semiconductor layer, and the first conductivity-type dopant is a p-type dopant and may include Mg, Zn, Ca, Sr, and Ba.

As another example of the light emitting structure 120 , the first conductivity-type semiconductor layer 115 may be implemented as a p-type semiconductor layer, and the second conductivity-type semiconductor layer 119 may be implemented as an n-type semiconductor layer. A third conductivity type semiconductor layer having a polarity opposite to that of the second conductivity type semiconductor layer may be formed on the second conductivity type semiconductor layer 119 . In addition, the light emitting structure 120 may be implemented as any one of an np junction structure, a pn junction structure, an npn junction structure, and a pnp junction structure.

An electrode layer 131 is formed under the second conductive semiconductor layer 119 . The electrode layer 131 may include a reflective layer. The electrode layer 131 may include an ohmic contact layer in contact with the second conductive semiconductor layer 119 of the light emitting structure 120 . The reflective layer may be selected from a material having a reflectance of 70% or more, for example, metals of Al, Ag, Ru, Pd, Rh, Pt, and Ir, and alloys of two or more of the above metals. The metal of the reflective layer may be in contact under the second conductivity type semiconductor layer 119 . The ohmic contact layer may be selected from a light-transmitting material, a metal, or a non-metal material.

The electrode layer 131 may include a stacked structure of a light-transmitting electrode layer/reflective layer, and the light-transmitting electrode layer may include, for example, indium tin oxide (ITO), indium zinc oxide (IZO), indium zinc tin oxide (IZTO), or indium aluminum (IAZO). zinc oxide), indium gallium zinc oxide (IGZO), indium gallium tin oxide (IGTO), aluminum zinc oxide (AZO), antimony tin oxide (ATO), gallium zinc oxide (GZO), Ag, Ni, Al, Rh, Pd , Ir, Ru, Mg, Zn, Pt, Au, Hf, and optional combinations thereof. A reflective layer made of a metallic material may be disposed under the light-transmitting electrode layer, for example, from among materials consisting of Ag, Ni, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Au, Hf, and selective combinations thereof. can be formed. As another example, the reflective layer may be formed in a distributed bragg reflection (DBR) structure in which two layers having different refractive indices are alternately disposed.

A light extraction structure such as roughness may be formed on the surface of at least one of the second conductive semiconductor layer 119 and the electrode layer 131, and this light extraction structure changes the critical angle of incident light, It can improve the light extraction efficiency.

The insulating layer 133 is disposed under the electrode layer 131 , a lower surface of the second conductive semiconductor layer 119 , side surfaces of the second conductive semiconductor layer 119 and the active layer 117 , and the It may be disposed in a partial region of the first conductivity type semiconductor layer 115 . The insulating layer 133 is formed in a region excluding the electrode layer 131 , the first electrode 135 , and the second electrode 137 in the lower region of the light emitting structure 120 . The lower part is electrically protected.

The insulating layer 133 includes an insulating material or insulating resin formed of at least one of oxide, nitride, fluoride, and sulfide having at least one of Al, Cr, Si, Ti, Zn, and Zr. The insulating layer 133 may be selectively formed from, for example, SiO ₂ , Si ₃ N ₄ , Al ₂ O ₃ , and TiO ₂ . The insulating layer 133 may be formed as a single layer or a multilayer, but is not limited thereto. The insulating layer 133 is formed to prevent an interlayer short circuit of the light emitting structure 120 when a metal structure for flip bonding is formed under the light emitting structure 120 .

The insulating layer 133 may be formed in a distributed bragg reflector (DBR) structure in which first and second layers having different refractive indices are alternately disposed, the first layer being SiO ₂ , Si ₃ N ₄ , Any one of Al ₂ O ₃ and TiO ₂ , and the second layer may be formed of any material other than the first layer, but is not limited thereto, or the first layer and the second layer are formed of the same material. Or it may be formed as a pair having three or more layers. In this case, the electrode layer may not be formed.

A first electrode 135 may be disposed under a portion of the first conductive semiconductor layer 115 , and a second electrode 137 may be disposed under a portion of the electrode layer 131 . A first connection electrode 141 is disposed under the first electrode 135 , and a second connection electrode 143 is disposed under the second electrode 137 .

The first electrode 135 is electrically connected to the first conductive semiconductor layer 115 and the first connection electrode 141 , and the second electrode 137 is connected to the second electrode layer 131 through the electrode layer 131 . It may be electrically connected to the second conductive semiconductor layer 119 and the second connection electrode 143 .

The first electrode 135 and the second electrode 137 are made of at least one of Cr, Ti, Co, Ni, V, Hf, Ag, Al, Ru, Rh, Pt, Pd, Ta, Mo, W or an alloy. may be formed, and may be formed in a single layer or in multiple layers. The first electrode 135 and the second electrode 137 may be formed in the same or different stacked structures. At least one of the first electrode 135 and the second electrode 137 may further have a current diffusion pattern such as an arm or finger structure. In addition, the first electrode 135 and the second electrode 137 may be formed in one or a plurality, but is not limited thereto. At least one of the first and second connection electrodes 141 and 143 may be disposed in plurality, but is not limited thereto.

The first connection electrode 141 and the second connection electrode 143 provide a lead function for supplying power and a heat dissipation path. The first connection electrode 141 and the second connection electrode 143 may include at least one of a circular shape, a polygonal shape, and a shape such as a circular pole or a polygonal pole. The first connection electrode 141 and the second connection electrode 143 are made of metal powder, for example, Ag, Al, Au, Cr, Co, Cu, Fe, Hf, In, Mo, Ni, Si, Sn, Ta. , Ti, W, and optional alloys of these metals. The first connection electrode 141 and the second connection electrode 143 may include In, Sn, Ni, Cu, and optional alloys thereof to improve adhesion between the first electrode 135 and the second electrode 137 . It may be plated with any one of the metals.

The support layer 140 includes a thermally conductive material and is disposed around the first electrode 135 , the second electrode 137 , the first connection electrode 141 , and the second connection electrode 143 . can be Lower surfaces of the first and second connection electrodes 141 and 143 may be exposed on a lower surface of the support layer 140 .

The supporting layer 140 is used as a layer supporting the light emitting device 100 . The support layer 140 is formed of an insulating material, and the insulating material is formed of, for example, a resin layer such as silicone or epoxy. As another example, the insulating material may include a paste or insulating ink. The material of the insulating material is polyacrylate resin, epoxy resin, phenolic resin, polyamides resin, polyimides rein, unsaturated polyesters resin, polyphenylene ether resin (PPE), polyphenilene oxide resin (PPO), polyphenylenesulfides resin, cyanate ester resin, benzocyclobutene (BCB), Polyamido-amine Dendrimers (PAMAM), and Polypropylene-imine, Dendrimers (PPI), and PAMAM-OS (organosilicon) having a PAMAM internal structure and an organosilicon outer surface. can be The support layer 140 may be formed of a material different from that of the insulating layer 133 .

At least one of compounds such as oxide, nitride, fluoride, and sulfide having at least one of Al, Cr, Si, Ti, Zn, and Zr may be added into the support layer 140 . Here, the compound added into the support layer 140 may be a heat spreader, and the heat spreader may be used as powder particles, grains, fillers, or additives of a predetermined size. The heat spreader includes a ceramic material, and the ceramic material is a co-fired low temperature co-fired ceramic (LTCC), high temperature co-fired ceramic (HTCC), and alumina. , quartz, calcium zirconate, forsterite, SiC, graphite, fusedsilica, mullite, cordierite, zirconia, beryllia ), and at least one of aluminum nitride. The ceramic material may be formed of a metal nitride having higher thermal conductivity than a nitride or oxide among insulating materials such as nitride or oxide, and the metal nitride may include, for example, a material having a thermal conductivity of 140 W/mK or more. The ceramic material is, for example, SiO ₂ , Si _x O _y , Si ₃ N ₄ , Si _x N _y , SiO _x N _y , Al ₂ O ₃ , BN, Si ₃ N ₄ , SiC (SiC-BeO), BeO, It may be a ceramic series such as CeO or AlN. The thermally conductive material may include a component of C (diamond, CNT).

The light emitting chip 100A is mounted on the circuit board 400 in a flip manner. The circuit board 400 includes a metal layer 471 , an insulating layer 472 on the metal layer 471 , a circuit layer (not shown) having a plurality of lead electrodes 473,474 on the insulating layer 472 , and the circuit layer and a protective layer 475 to protect the The metal layer 471 is a heat dissipation layer, and includes a metal having high thermal conductivity, for example, a metal such as Cu or Cu-alloy, and may be formed in a single-layer or multi-layer structure.

The insulating layer 472 insulates between the metal layer 471 and the circuit layer. The insulating layer may include at least one of a resin material such as epoxy, silicone, glass fiber, prepreg, polyphthalamide (PPA), liquid crystal polymer (LCP), and polyamide9T (PA9T). . In addition, an additive such as a metal oxide, for example, TiO ₂ , SiO ₂ , Al ₂ O ₃ may be added in the insulating layer 472 , but the present disclosure is not limited thereto. As another example, the insulating layer 472 may be used by adding a material such as graphene into an insulating material such as silicon or epoxy, but is not limited thereto.

The insulating layer 472 may be an anodized region in which the metal layer 471 is formed by an anodizing process. Here, the metal layer 471 may be made of aluminum, and the anodized region may be made of a material such as Al ₂ O ₃ .

The first and second lead electrodes 473,474 are electrically connected to the first and second connection electrodes 141 and 143 of the light emitting chip 100A. Conductive adhesives 461 and 462 may be disposed between the first and second lead electrodes 473,474 and the connection electrodes 141 and 143 of the light emitting chip 100A. The conductive adhesives 461 and 462 may include a metal material such as a solder material. The first lead electrode 473 and the second lead electrode 474 are circuit patterns and supply power.

The passivation layer 475 may be disposed on the circuit layer. The protective layer 475 includes a reflective material, and may be formed of, for example, a resist material, for example, a white resist material, but is not limited thereto. The passivation layer 475 may function as a reflective layer, and may be formed of, for example, a material having a higher reflectance than an absorptivity. As another example, the protective layer 475 may be formed of a material absorbing light, and the light absorbing material may include a black resist material.

A second example of the light emitting device of the light emitting module will be described with reference to FIG. 18 .

Referring to FIG. 18 , the light emitting device 100 includes a light emitting chip 100B. The light emitting device 100 may include a light emitting chip 100B and a phosphor layer 150 disposed on the light emitting chip 100B. The phosphor layer 150 includes at least one or a plurality of blue, green, yellow, and red phosphors, and may be disposed in a single layer or in multiple layers. In the phosphor layer 150, a phosphor is added in a light-transmitting resin material. The light-transmitting resin material may include a material such as silicone or epoxy, and the phosphor may be selectively formed from among YAG, TAG, Silicate, Nitride, and Oxy-nitride-based materials.

The phosphor layer 150 may be disposed on the upper surface of the light emitting chip 100B, or may be disposed on the upper surface and side surfaces of the light emitting chip 100B. The phosphor layer 150 may be disposed on a region where light is emitted from the surface of the light emitting chip 100B, and may convert a wavelength of light.

The light emitting chip 100B includes a substrate 111 , a first semiconductor layer 113 , a light emitting structure 120 , an electrode layer 131 , an insulating layer 133 , a first electrode 135 , and a second electrode 137 . , a first connection electrode 141 , a second connection electrode 143 , and a support layer 140 . The substrate 111 and the second semiconductor layer 113 may be removed.

The light emitting chip 100B of the light emitting device 100 and the circuit board 400 may be connected to each other through connection electrodes 161 and 162 , and the connection electrodes 161 and 162 may include a conductive pump, that is, a solder bump. The conductive pump may be arranged in one or a plurality under each of the electrodes 135 and 137, but is not limited thereto. The insulating layer 133 may expose the first and second electrodes 135 and 137 , and the first and second electrodes 135 and 137 may be electrically connected to the connection electrodes 161 and 162 .

A third example of the light emitting device will be described with reference to FIG. 19 .

Referring to FIG. 19 , the light emitting device 100 includes a light emitting chip 200A connected to a circuit board 400 . The light emitting device 100 may include a phosphor layer 250 disposed on the surface of the light emitting chip 200A. The phosphor layer 250 converts the wavelength of the incident light. As shown in FIG. 4 , an optical lens ( 300 in FIG. 4 ) is disposed on the light emitting device 100 to adjust the directivity of light emitted from the light emitting chip 200A.

The light emitting chip 200A includes a light emitting structure 225 and a plurality of pads 245 and 247 . The light emitting structure 225 may be formed of a compound semiconductor layer of a group II to group VI element, for example, a compound semiconductor layer of a group III-V element or a compound semiconductor layer of a group II-VI element. The plurality of pads 245 and 247 are selectively connected to the semiconductor layer of the light emitting structure 225 and supply power.

The light emitting structure 225 includes a first conductivity type semiconductor layer 222 , an active layer 223 , and a second conductivity type semiconductor layer 224 . The light emitting chip 200A may include a substrate 221 . The substrate 221 is disposed on the light emitting structure 225 . The substrate 221 may be, for example, a light-transmitting, insulating substrate, or a conductive substrate. For such a configuration, reference will be made to the description of the light emitting structure and the substrate of FIG. 4 .

Pads 245 and 247 are disposed below the light emitting chip 200A, and the pads 245 and 247 include first and second pads 245 and 247 . The first and second pads 245 and 247 are disposed under the light emitting chip 200A to be spaced apart from each other. The first pad 245 is electrically connected to the first conductive semiconductor layer 222 , and the second pad 247 is electrically connected to the second conductive semiconductor layer 224 . The first and second pads 245 and 247 may have a polygonal or circular bottom shape, or may be formed to correspond to the shapes of the first and second lead electrodes 415 and 417 of the circuit board 400 . A lower surface area of each of the first and second pads 245 and 247 may be formed to have a size corresponding to a size of the upper surface of each of the first and second lead electrodes 415 and 417 , for example.

The light emitting chip 200A may include at least one of a buffer layer (not shown) and an undoped semiconductor layer (not shown) between the substrate 221 and the light emitting structure 225 . The buffer layer is a layer for alleviating a difference in lattice constant between the substrate 221 and the semiconductor layer, and may be selectively formed from group II to group VI compound semiconductors. An undoped group III-V compound semiconductor layer may be further formed under the buffer layer, but is not limited thereto. The substrate 221 may be removed. When the substrate 221 is removed, the phosphor layer 250 may be in contact with an upper surface of the first conductive semiconductor layer 222 or an upper surface of another semiconductor layer.

The light emitting chip 200A includes first and second electrode layers 241,242 , a third electrode layer 243 , and insulating layers 231,233 . Each of the first and second electrode layers 241,242 may be formed as a single layer or a multilayer, and may function as a current diffusion layer. The first and second electrode layers 241,242 may include a first electrode layer 241 disposed under the light emitting structure 225; and a second electrode layer 242 disposed under the first electrode layer 241 . The first electrode layer 241 diffuses the current, and the second electrode layer 241 reflects the incident light.

The first and second electrode layers 241,242 may be formed of different materials. The first electrode layer 241 may be formed of a light-transmitting material, for example, a metal oxide or a metal nitride. The first electrode layer is, for example, indium tin oxide (ITO), ITO nitride (ITON), indium zinc oxide (IZO), IZO nitride (IZON), indium zinc tin oxide (IZTO), indium aluminum zinc oxide (IAZO), or IGZO (indium zinc oxide). Indium gallium zinc oxide), indium gallium tin oxide (IGTO), aluminum zinc oxide (AZO), antimony tin oxide (ATO), and gallium zinc oxide (GZO) may be selectively formed. The second electrode layer 242 may be in contact with a lower surface of the first electrode layer 241 and function as a reflective electrode layer. The second electrode layer 242 includes a metal, for example, Ag, Au, or Al. The second electrode layer 242 may partially contact the lower surface of the light emitting structure 225 when a portion of the first electrode layer 241 is removed.

As another example, the structure of the first and second electrode layers 241,242 may be stacked in an Omni Directional Reflector layer (ODR) structure. The non-directional reflective structure may be formed as a stacked structure of a first electrode layer 241 having a low refractive index and a second electrode layer 242 made of a highly reflective metal material in contact with the first electrode layer 241 . The electrode layers 241,242 may have, for example, a stacked structure of ITO/Ag. The omnidirectional reflection angle at the interface between the first electrode layer 241 and the second electrode layer 242 may be improved.

As another example, the second electrode layer 242 may be removed, and may be formed of a reflective layer of a different material. The reflective layer may be formed in a distributed bragg reflector (DBR) structure, wherein the distributed Bragg reflector structure includes a structure in which two dielectric layers having different refractive indices are alternately disposed, for example, a SiO ₂ layer , Si ₃ N ₄ layer, TiO ₂ layer, Al ₂ O ₃ layer, and may include a different one of the MgO layer, respectively. As another example, the electrode layers 241,242 may include both a distributed Bragg reflective structure and a non-directional reflective structure, and in this case, the light emitting chip 200A having a light reflectance of 98% or more may be provided. The light emitting chip 200A mounted in the flip method emits light reflected from the second electrode layer 242 through the substrate 221 , so that most of the light may be emitted in the vertical direction. In addition, the light emitted to the side surface of the light emitting chip 200A may be reflected by the reflective sheet 600 to the incident surface area of the optical lens.

The third electrode layer 243 is disposed under the second electrode layer 242 and is electrically insulated from the first and second electrode layers 241,242 . The third electrode layer 243 may be formed of a metal, for example, titanium (Ti), copper (Cu), nickel (Ni), gold (Au), chromium (Cr), tantalum (Ta), platinum (Pt), or tin (Sn). ), silver (Ag), and phosphorus (P). A first pad 245 and a second pad 247 are disposed under the third electrode layer 243 . The insulating layers 231,233 block unnecessary contact between the layers of the first and second electrode layers 241,242 , the third electrode layer 243 , the first and second pads 245 and 247 , and the light emitting structure 225 . The insulating layers 231,233 include first and second insulating layers 231,233. The first insulating layer 231 is disposed between the third electrode layer 243 and the second electrode layer 242 . The second insulating layer 233 is disposed between the third electrode layer 243 and the second pads 245 and 247 . The first and second pads 245 and 247 may include the same material as the first and second lead electrodes 415 and 417 .

The third electrode layer 243 is connected to the first conductivity type semiconductor layer 222 . The connection part 244 of the third electrode layer 243 protrudes into a via structure through the lower portions of the first and second electrode layers 241 and 242 and the light emitting structure 225 and is in contact with the first conductive semiconductor layer 222 . do. The connection part 244 may be disposed in plurality. A portion 232 of the first insulating layer 231 extends around the connecting portion 244 of the third electrode layer 243, so that the third electrode layer 243, the first and second electrode layers 241,242, and the second It blocks the electrical connection between the conductive semiconductor layer 224 and the active layer 223. An insulating layer may be disposed on a side surface of the light emitting structure 225 for side protection, but is not limited thereto.

The second pad 247 is disposed under the second insulating layer 233 and makes contact with at least one of the first and second electrode layers 241 and 242 through an open area of the second insulating layer 233 . or connected The first pad 245 is disposed under the second insulating layer 233 and is connected to the third electrode layer 243 through an open area of the second insulating layer 233 . Accordingly, the protrusions 248 of the first pad 247 are electrically connected to the second conductive semiconductor layer 224 through the first and second electrode layers 241,242 , and the protrusions 246 of the second pad 245 . ) is electrically connected to the first conductivity type semiconductor layer 222 through the third electrode layer 243 .

The first and second pads 245 and 247 are spaced apart from each other under the light emitting chip 200A, and face the first and second lead electrodes 415 and 417 of the circuit board 400 . The first and second pads 245 and 247 may include polygonal recesses 271,273 , and the recesses 271,273 are convex in the direction of the light emitting structure 225 . The recesses 271,273 may be formed to have a depth equal to or smaller than the thicknesses of the first and second pads 245 and 247, and the depths of the recesses 271,273 are the first and second pads 245 and 247. can increase the surface area of

Bonding members 255 and 257 are disposed in the region between the first pad 245 and the first lead electrode 415 and in the region between the second pad 247 and the second lead electrode 417 . The bonding members 255 and 257 may include an electrically conductive material, and some are disposed in the recesses 271 and 273 . Since the bonding members 255 and 257 of the first and second pads 215 and 217 are disposed in the recesses 271,273, the bonding area between the bonding members 255 and 257 and the first and second pads 245 and 247 may be increased. have. Accordingly, since the first and second pads 245 and 247 and the first and second lead electrodes 415 and 417 are bonded, the electrical reliability and heat dissipation efficiency of the light emitting chip 200A may be improved.

The bonding members 255 and 257 may include a solder paste material. The solder paste material includes at least one of gold (Au), tin (Sn), lead (Pb), copper (Cu), bismuth (Bi), indium (In), and silver (Ag). Since the bonding members 255 and 257 directly conduct heat transfer to the circuit board 400 , heat conduction efficiency may be improved compared to a structure using a package. In addition, since the bonding members 255 and 257 are a material having a small difference in coefficients of thermal expansion between the first and second pads 245 and 247 of the light emitting chip 200A, heat conduction efficiency may be improved.

As another example, the bonding members 255 and 257 may include a conductive film, wherein the conductive film includes one or more conductive particles in an insulating film. The conductive particles may include, for example, at least one of a metal, a metal alloy, and carbon. The conductive particles may include at least one of nickel, silver, gold, aluminum, chromium, copper, and carbon. The conductive film may include an anisotropic conductive film or an anisotropic conductive adhesive.

An adhesive member, for example, a thermally conductive film may be included between the light emitting chip 200A and the circuit board 400 . The thermally conductive film may include a polyester resin such as polyethylene terephthalate, polybutyrene terephthalate, polyethylene naphthalate, and polybutyrene naphthalate; polyimide resin; acrylic resin; styrene-based resins such as polystyrene and acrylonitrile-styrene; polycarbonate resin; polylactic acid resin; polyurethane resin; etc. can be used. In addition, polyolefin resins such as polyethylene, polypropylene, and ethylene-propylene copolymer; vinyl resins such as polyvinyl chloride and polyvinylidene chloride; polyamide resin; sulfone-based resins; polyether-etherketone-based resins; allylate-based resin; or at least one of a blend of the above resins.

The light emitting chip 200A may improve light extraction efficiency by emitting light through the surface of the circuit board 400 and the side and upper surfaces of the light emitting structure 225 . Since the light emitting chip 200A can be directly bonded to the circuit board 400 , the process can be simplified. In addition, since the heat dissipation of the light emitting chip 200A is improved, it may be usefully utilized in the lighting field.

20 is a side cross-sectional view illustrating a display device having a light emitting module according to an exemplary embodiment.

Referring to FIG. 20 , the display device 500 includes a light emitting module 301 disposed on a bottom cover 510 , and an optical sheet 514 and a display panel 515 are disposed on the light emitting module 301 . .

The bottom cover 510 may include a metal or a thermally conductive resin material for heat dissipation. The bottom cover 510 may include an accommodating part 560 , and a side cover may be provided around the accommodating part 560 .

The light emitting module 301 may be disposed on the bottom cover 510 in one or a plurality of rows. The light emitting module 301 may emit white light by the light emitting device 100, but is not limited thereto.

The light emitting module 301 includes a light emitting device 100 , an optical lens 300 on each light emitting device 100 , and a circuit board 400 on which a plurality of light emitting devices 100 are mounted. The circuit board 400 may be a printed circuit board (PCB, Printed Circuit Board) including a circuit pattern (not shown), for example, a resin material PCB, a metal core PCB (MCPCB, Metal Core PCB), a flexible PCB ( FPCB, Flexible PCB), etc., but is not limited thereto.

A reflective sheet 517 is disposed on the circuit board 400 , the reflective sheet 517 includes an off region 518 , and an optical lens 300 is coupled to the open region 518 . As the optical lens 300 protrudes through the open area 518 of the reflective sheet 517 , the emitted light of the optical lens 300 transmits or reflects the optical sheet 514 , and the reflected light is It may be reflected back by the reflective sheet 517 . Accordingly, the uniformity of the luminance distribution of the backlight oil unit 510 may be improved.

The reflective sheet 517 may be formed of, for example, PET, PC, or PVC resin, but is not limited thereto.

The optical sheet 514 may include at least one of prism sheets for collecting dispersed light, a luminance enhancing sheet, and a diffusion sheet for re-diffusing the light. A light guide layer (not shown) may be disposed in a region between the optical sheet 514 and the light emitting module 301 , but is not limited thereto.

A display panel 515 may be disposed on the optical sheet 514 . The display panel 515 may display an image by the incident light. The display panel 515 is, for example, an LCD panel, and includes first and second substrates made of transparent materials that face each other, and a liquid crystal layer interposed between the first and second substrates. A polarizing plate may be attached to at least one surface of the display panel 515 , but the structure of the polarizing plate is not limited thereto. The display panel 515 displays information by the light passing through the optical sheet 514 . The display device 500 may be applied to various types of portable terminals, a monitor of a notebook computer, a monitor of a laptop computer, a TV, and the like.

The light emitting module according to the embodiment may be applied to a light unit. The light unit may include a structure having one or a plurality of light emitting modules, and may include a three-dimensional display, various lighting lamps, traffic lights, vehicle headlights, electric signs, and the like.

Features, structures, effects, etc. described in the above embodiments are included in at least one embodiment of the present invention, and are not necessarily limited to only one embodiment. Furthermore, features, structures, effects, etc. illustrated in each embodiment can be combined or modified for other embodiments by those of ordinary skill in the art to which the embodiments belong. Accordingly, the contents related to such combinations and modifications should be interpreted as being included in the scope of the present invention.

In addition, although the embodiment has been described above, it is only an example and does not limit the present invention, and those of ordinary skill in the art to which the present invention pertains are exemplified above in a range that does not depart from the essential characteristics of the present embodiment. It can be seen that various modifications and applications that have not been made are possible. For example, each component specifically shown in the embodiment can be implemented by modification. And the differences related to these modifications and applications should be construed as being included in the scope of the present invention defined in the appended claims.

100: light emitting element 100A, 110B, 200A: light emitting chip
301: light emitting module 150,250: phosphor layer
300: optical lens 315: recess
320: incident surface 310: bottom surface
330: first light exit surface 335: first light exit surface
400: circuit board 514: optical sheet
517: reflective sheet

Claims (21)

bottom surface;
an incident surface having a convex recess from the bottom surface to which light is incident;
a first light emitting surface emitting light incident on the incident surface and having a convex curved surface; and
and a second light exit surface extending from an outer lower periphery of the first light exit surface toward the bottom surface,
The recess has a depth of 80% or more of a distance between the apex of the first light exit surface and the bottom surface,
A region overlapping the recess in a vertical direction among regions of the first light emitting surface includes a convex curved surface,
The first light exit surface has different radii of curvature, and centers of circles having different radii of curvature are disposed below a straight line horizontal to the vertex of the incident surface,
The second light exit surface has an exit angle smaller than the incidence angle of the first light incident to the incidence surface,
A boundary point between the bottom surface and the incident surface is a first edge,
A boundary point between the bottom surface and the second light exit surface is a second edge,
The upper end of the second light emitting surface is a third edge,
The angle between the vertex of the incident surface and the line segment connecting the first edge with respect to the optical axis has a first angle,
A first straight line connecting the first edge and the second edge is inclined at a second angle with respect to a first axis direction orthogonal to the optical axis,
The first angle is greater than the second angle,
An apex of the incident surface is disposed higher than a horizontal straight line passing from the third edge toward the recess. According to claim 1, wherein the second light exit surface is inclined at a third angle,
The third angle is an angle between a straight line connecting the second edge from the third edge and a perpendicular straight line,
The first angle is at least 4 times greater than the second angle,
The second angle is greater than the third angle of the optical lens. According to claim 1, wherein the bottom surface comprises a concave curved surface or a total reflection surface,
The second light emitting surface is disposed at an obtuse angle with a first straight line connecting the first and second edges of the bottom surface,
The first edge is an optical lens disposed lower than the second edge. 4. The method according to any one of claims 1 to 3, wherein the depth of the recess is greater than the lower width of the incident surface,
The first light exit surface has a convex curved surface from the apex of the first light exit surface to the outer lower end,
An optical lens having the highest height of the apex of the first light emitting surface on the first light emitting surface and gradually lowering from the apex of the first light emitting surface to the lower outer side. According to claim 4, comprising a plurality of support projections protruding from the bottom surface,
The vertical width of the second light exit surface is at least 1.5 times the distance between the apex of the recess and the first light exit surface. a light emitting device emitting light through an upper surface and a plurality of side surfaces; and
It includes an optical lens disposed on the light emitting device,
The optical lens is
sloping floor;
an incident surface having a recess concave from the bottom surface and on which the light emitting element is disposed;
a first light emitting surface emitting the light incident on the incident surface and having a convex curved surface; and
a second light exit surface extending from a lower periphery of the first light exit surface toward the bottom surface;
The depth of the recess is at least 80% of the thickness of the optical lens,
An emitting angle of the first light emitted to the second light emitting surface through the incident surface is smaller than an incident angle of the incident surface with respect to the optical axis,
Of the light incident through the incident surface, an emission angle of the second light reflected by the bottom surface and emitted to the second light emission surface is smaller than the incidence angle of the incident surface with respect to the optical axis,
The incident surface and the first light exit surface have different centers of radii of curvature, and the centers of circles having different radii of curvature are disposed below a straight line horizontal to the vertex of the incident surface,
A boundary point between the bottom surface and the incident surface is a first edge,
A boundary point between the bottom surface and the second light exit surface is a second edge,
The upper end of the second light emitting surface is a third edge,
A first angle is formed between the line segment between the vertex of the incident surface and the first edge with respect to the optical axis,
The first angle is greater than an angle between a straight line connecting the first and second edges and a first straight line perpendicular to the optical axis,
The vertex of the incident surface is disposed higher than a horizontal straight line passing from the third edge toward the recess. The method according to claim 6, wherein a region overlapping the recess in a vertical direction among regions of the first light exit surface includes a flat surface or a convex curved surface,
The bottom surface is a light emitting module including a concave curved surface or a total reflection surface. 8. The method of claim 7,
It includes a circuit board disposed under the light emitting device,
The optical lens includes a plurality of support protrusions protruding from the bottom surface toward the circuit board,
The top surface of the circuit board includes an absorption layer for absorbing the light transmitted to the bottom surface,
The absorption layer is disposed in regions opposite to each other with respect to the light emitting device,
a region on the circuit board in which the absorption layer is disposed is disposed below a region in which the amount of light reflected from the first light emitting surface is maximally transmitted to the reflective surface. 9. The method according to any one of claims 6 to 8,
An angle between a first straight line connecting both ends of the bottom surface and an optical axis perpendicular to the recess is smaller than an angle between the second light exit surface and the first straight line,
The second light emitting surface is disposed at an obtuse angle with the first straight line,
The depth of the recess is greater than the lower width of the incident surface,
The first edge is lower than the second edge of the second light emitting surface of the light emitting module. 9. The method according to any one of claims 6 to 8,
The distance between the apex of the recess and the first width within the recess, the ratio of the distance between the apex of the recess and the apex of the first light exit surface satisfies the range of 0.5:1 to 1:1
The first width of the light emitting module is the same width as the width of the light emitting element in the region of the recess.
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