KR20180073763A - Flat Panel Display Embedding Optical Imaging Sensor - Google Patents

Abstract

The present invention relates to a flat panel display device having an embedded image sensor such as a fingerprint recognizing sensor. According to the present invention, the flat panel display device having an embedded image recognizing sensor, comprises a display panel and a directional light unit. In the display panel, a display area and a non-display area are defined. The directional light unit has a length, a width, and a constant thickness to accommodate the display panel, and is attached to an upper surface of the display panel. The directional optical unit includes a cover substrate, a light emitting element, a light incident element, and a light source. The cover substrate has an area corresponding to a length and a width thereof. The light emitting element is arranged in the display area on a lower surface of the cover substrate. The light incident element is arranged in the non-display area on the lower surface of the cover substrate. The light source is arranged to face the light incident element at one side of the display panel.

Description

Technical Field [0001] The present invention relates to a flat panel display (LCD)

The present invention relates to a flat panel display device incorporating an image sensor such as a fingerprint recognition sensor. More particularly, the present invention relates to a flat panel display device incorporating an optical image sensor including an optical image sensor and a super thin film substrate for providing a directional light.

With the development of computer technology, various kinds of applications such as a notebook computer, a tablet PC, a smart phone, a personal digital assistant, an automated teller machine, a search guide system, A computer based system has been developed. These systems typically store many confidential data, such as business information and business secrets, as well as personal information related to personal privacy, so there is a need to enhance security to protect these data.

For this purpose, a method of enhancing security using an image sensor capable of recognizing biometric information has been proposed. For example, fingerprint sensors are known that can enhance security by registering or authenticating a system using a fingerprint of a finger. The fingerprint sensor is a sensor that detects a human fingerprint. The fingerprint sensor is roughly classified into an optical fingerprint sensor and a capacitive fingerprint sensor.

The optical fingerprint sensor uses a light source such as an LED (Light Emitting Diode) to illuminate the light and reflects the light reflected by the ridge of the fingerprint through a CMOS (Complementary Metal Oxide Semiconductor) image sensor It is based on the principle of sensing. Optical fingerprint sensors require additional equipment for scanning because they must be scanned using LEDs. There is a limitation in increasing the size of the scannable image. Therefore, there are limitations in various applications such as coupling with a display device.

As a conventional optical fingerprint sensor, Korean Registered Patent No. 10-0608171 entitled " Image Display Device with a Fingerprint Recognition Sensor "filed on July 26, 2006, and Korean Patent Registration No. 10-0608171 published on April 21, Korean Patent Publication No. 10-2016-0043216 entitled " Display Device Including Device "is known.

The display device having the optical fingerprint sensor described in the Korean Laid Open Publication is configured so that the display area of the display device can be used simultaneously as the touch area and the fingerprint recognition area. However, the sensing light for fingerprint recognition uses a diffusion light having a significantly low directivity (or directivity). Therefore, there is a limit in recognizing the pattern of the correct fingerprint. When a collimated light such as a laser beam having high directivity is used, it is difficult to irradiate a light for sensing over a large area, so that the size of the fingerprint recognition area is extremely limited. In addition, in order to apply the highly directional collimated light to a wide scan area, it is difficult to apply the scan function to a portable flat panel display device.

Therefore, in a display device incorporating a fingerprint recognition sensor, a capacitance type fingerprint sensor is mainly applied. However, capacitance type fingerprint sensors also have many problems.

A capacitive fingerprint sensor uses a difference in the quantity of electricity charged between a ridge and a valley in contact with a fingerprint sensor. As a conventional capacitive fingerprint sensor, US Patent Publication No. US 2013/0307818 entitled " Capacitive Sensor Packaging ", published on Nov. 21, 2013, is known.

The capacitive fingerprint sensor disclosed in the above-mentioned U.S. patent publication is configured in the form of an assembly combined with a specific push button, and a circuit for measuring the capacitance between the capacitive plate and the fingerprint (ridge and valley) of the user is printed Lt; / RTI > wafer. Generally, ridges and valleys of human fingerprints are very small with a size of about 300 μm to 500 μm. Therefore, the capacitive type fingerprint sensor of the US publication needs a high-resolution sensor array and an integrated chip (IC) for fingerprint recognition processing And a silicon wafer capable of integrally forming a sensor array and an IC is used for this purpose.

However, when a high-resolution sensor array and an IC are formed together using a silicon wafer, an assembly structure for combining a fingerprint sensor with a push button is required, which not only complicates the configuration but also increases the non-display area (bezel area) . Further, since the push button (for example, the home key of the smart phone) and the fingerprint sensor are formed to overlap with each other, the thickness of the push button is increased, and the fingerprint sensing area is dependent on the size of the push button.

In order to solve such a problem, a technique of using the area of the touch sensor screen as a fingerprint identification area has been developed. US Patent No. 8,564, 314 entitled " Capacitive Touch Sensor for Identifying a Fingerprint ", entitled " Fingerprint Identification Integrated Capacitive Touch Screen Korean Patent No. 10-1432988, which was registered on Aug. 18, 2014, is known.

A personal portable display device such as a smart phone is often provided with a protective film for protecting the display panel. When the above-described technique is applied to the display area of the personal portable display device as a fingerprint recognition area, the fingerprint recognition function may significantly deteriorate when a protective film is attached. Generally, even if a protective film is attached, the touch function can be used as it is. However, since fingerprint recognition must recognize very fine fingerprints, it is necessary to detect minute changes in capacitance. No matter how thin the thickness of the protective film can be, it can cause serious obstacles to accurately sensing the change in capacitance required to recognize a fine fingerprint.

In a display device incorporating a capacitance type fingerprint sensor, a protective film or a tempered glass is often attached to the outer surface of the display device. In this case, the recognition ability may be significantly deteriorated. Therefore, in the case of the capacitance type fingerprint sensor, there may arise a problem with the thickness of the display substrate. On the other hand, in a display device incorporating an optical fingerprint sensor, accurate reading ability is difficult because scattered light is used. When a collimated light is used to ensure accurate recognition capability, it is difficult to combine with a highly portable flat display device because a complicated and bulky optical device is required.

It is an object of the present invention to provide a flat panel display device incorporating an ultra-thin film optical image recognition sensor designed to overcome the above problems. Another object of the present invention is to provide a flat panel display device with a super thin film type optical image recognition sensor having a high detection resolution and sensitivity by accurately irradiating the directional light to the detection region and refracting the reflected detection light in the vertical direction have.

In order to achieve the above object, an image recognition sensor built-in flat panel display device according to the present invention includes a display panel and a directional light unit. The display panel defines a display area and a non-display area. The directional light unit has a length, a width, and a constant thickness that accommodate the display panel, and is attached to the upper surface of the display panel. The directional light unit includes a cover substrate, an outgoing element, an incident element, and a light source. The cover substrate has an area corresponding to the length and the width. The light exiting element is disposed in the display area on the lower surface of the cover substrate. The light-incident element is arranged in the non-display area on the lower surface of the cover substrate. The light source is disposed so as to face the light-incident element at one side of the display panel.

In one example, the light source provides incident light at an incident point defined on the surface of the light-incident element. The light-incident element has a holographic pattern for converting incident light into scanning light having a diffusing angle for totally reflecting the incident light on the surface of the cover substrate and entering the inside of the cover substrate. The light-exiting element has a holographic pattern for converting the emitted light, which has been totally reflected from the upper surface of the cover substrate by the scanning light, into detection light emitted in a direction perpendicular to the lower surface of the cover substrate.

For example, the diffusing angle includes a horizontal diffusing angle and a vertical diffusing angle. The horizontal diffusion angle is an angle that diffuses on a horizontal plane formed by the longitudinal direction and the width direction of the cover substrate. The vertical diffusion angle is an angle that diffuses on a vertical plane formed by the longitudinal direction and the thickness direction of the cover substrate.

For example, the scanning light diffuses between the first scanning light having the first incident angle on the vertical plane and the second scanning light having the second incident angle.

In one example, the outgoing light diffuses between the first outgoing light in which the first scanning light is totally reflected on the upper surface of the cover substrate and the second outgoing light in which the second scanning light is totally reflected on the upper surface of the cover substrate.

For example, the detection light is emitted to the outside of the cover substrate between the first detection light refracted by the light emitting element by the first emitted light and the second detection light refracted by the light emitting element by the second emitted light.

For example, the range in which the scanning light is irradiated on the upper surface of the cover substrate is defined as a sensing area for positioning an image object to be recognized. The range in which the detection light is emitted is defined as a sensor area in which the optical sensor is disposed.

For example, the display panel and the directional light substrate are surface-bonded through an optical adhesive.

In one example, the light source provides a collimated light whose cross-sectional shape is prestigious.

The present invention can provide a flat panel display with an optical image recognition sensor having high resolution image recognition capability by providing directional light as detection light. The present invention can provide an optical image recognition sensor built-in flat panel display device with high accuracy by diffusing and providing an infrared laser having a dot cross-sectional area provided by a point light source using a holographic technique to a sensing area defined in a display panel. In particular, since the detection light is incident perpendicularly on the display substrate provided with the image recognition sensor, the light amount of the detection light is not degraded, and accurate image recognition results can be obtained. Further, in the present invention, the protective substrate itself attached to the first surface of the display device can be used as the cover substrate of the directional light substrate according to the present invention. Therefore, even when the optical image recognition apparatus according to the present invention is combined with the display apparatus, the thickness of the display apparatus is not increased. Since the image recognition area can be freely set within the display area of the display panel, the flat panel display device with an optical image recognition sensor according to the present invention can be applied to various products.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a view showing the structure of a directional light substrate applied to a flat panel display device incorporating an optical image sensor according to a preferred embodiment of the present invention. Fig.
BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to an optical image sensor and a flat panel display.
3 is a sectional view showing the structure of an optical image sensor built-in type liquid crystal display device including a directional light unit and an optical recognition sensor according to a first application example of the present invention.
4 is a cross-sectional view showing a structure of an optical image sensor built-in organic light emitting diode display device including a directional light unit and an optical recognition sensor according to a second application example of the present invention.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. Like reference numerals throughout the specification denote substantially identical components. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the following description, a detailed description of known technologies or configurations related to the present invention will be omitted when it is determined that the gist of the present invention may be unnecessarily obscured. In addition, the component names used in the following description may be selected in consideration of easiness of specification, and may be different from the parts names of actual products.

Hereinafter, an embodiment of the present invention will be described with reference to Fig. 1 is a view showing a structure of a directional light unit applied to a flat panel display device incorporating an optical image sensor according to a preferred embodiment of the present invention. 1 is a side view as viewed from an XZ plane, and the lower drawing is a plan view as viewed from an XY plane from above.

Referring to FIG. 1, a directional light unit according to a preferred embodiment of the present invention includes a directional light substrate SLS and a light source LS. The directional light substrate SLS includes a cover substrate CP, an outgoing light element GHOE, and a light incident element CHOE. The cover substrate CP has a substantially rectangular plate shape, and has a length, a width, and a thickness. In Fig. 1, the length corresponds to the X axis, the width corresponds to the Y axis, and the thickness corresponds to the Z axis.

The directional optical unit is an optical device that provides limited reproduction of collimated light to a predetermined sensing area (or detection area) and provides light replicated with an image. Thus, the light source LS preferably provides collimated light.

A sensing area SA (or detection area) is defined on the upper surface of the cover substrate CP. In the case of a fingerprint recognition device, it is preferable that the sensing area SA be set at a position suitable for the user to place his / her fingerprint on the surface of the cover substrate CP. For example, in the rectangular cover substrate CP, a rectangular region can be defined at the center portion of the 1/3 point from the lower side. In this case, the sensing area SA may have a size of 4 mm X 4 mm to 10 mm X 10 mm. Here, 4 mm X 4 mm is set considering the minimum size for fingerprint recognition. In addition, 10 mm X 10 mm is set considering the average size of a thumbprint of a general person.

An incident light element (CHOE) and an outgoing light element (GHOE) are attached to the lower surface of the cover substrate (CP). The light-incident element CHOE is an optical element which diffuses and expands the light having a cross-sectional area provided by the light source LS corresponding to the sensing area SA. Since the light-incident element is not directly related to (CHOE) image recognition, it is preferable to arrange the light-incident element in the outer region of the light-exiting element (GHOE). Particularly, the light-incident element CHOE is disposed opposite to the light source LS.

The outgoing element (GHOE) is an optical element that transmits the light used for image detection to the image sensor. The light exiting element (GHOE) is disposed in an area where light reflected by the object disposed on the surface of the sensing area (SA) arrives. In particular, the outgoing element (GHOE) is preferably a holographic element that provides detection light in a direction perpendicular to the lower surface of the cover substrate (CP) to enhance the accuracy of image detection. The outgoing element GHOE is preferably a holographic optical element that provides detection light to the outside of the directional light substrate SLS, particularly to an image sensor (or detector) disposed outside the lower surface of the cover substrate CP.

A light source LS is arranged in the lower space of the light-incoming element CHOE so as to face the light-incoming element CHOE. In particular, it is preferable that the light source LS is opposed to the light incident element CHOE. It is desirable that the light source LS provide high collimation light such as a laser. When applied to a system incorporating a fingerprint recognition function in a portable display device, it is desirable to provide an infrared laser, which is light that can not be perceived by a person.

The collimated light provided in the light source LS is provided as an incident point IP having a point shape cross section as an incident light 100 and defined in the light incident element CHOE. The incident light 100 is preferably incident on the surface of the incident point IP in the normal direction. However, the present invention is not limited to this, and it may be incident at an inclined angle with respect to the normal line of the surface of the incident point IP, if necessary.

The light incident element CHOE provides scanning light (or scan light) 200, 210 for image detection of the incident light 100 provided by the light source LS. The scanning lights 200 and 210 are the light refracted inside the cover substrate CP to satisfy the total reflection condition on the upper surface of the cover substrate CP. It is preferable that the light incident element CHOE has an area larger than the incident point IP at which the incident light 100 is irradiated. For example, when the cross-sectional area of the collimated light provided by the light source LS is in the garden of 0.5 mm x 0.5 mm, the light-incident element CHOE is disposed at the center of the cover substrate CP and has a width of about 3 mm to 5 mm And may have a rectangular shape with a length.

The scanning light 200 and 210 converted by the light incident element CHOE by the incident light 100 which is a point-like straight light is diffused into an area corresponding to the sensing area SA defined on the upper surface of the cover substrate CP . In order to extend the light source LS having a pointed cross section to the sensing area SA having a certain area, the light incident element CHOE has a vertical diffusion angle? That is a diffusion angle on the XZ plane and a horizontal diffusion angle? So as to diffuse the incident light.

The scanning light 200, 210 used for image detection is totally reflected on the surface of the cover substrate CP and proceeds to the lower surface as the outgoing light 300, 310. It is preferable that the light exiting element GHOE is a holographic optical element which changes the direction of travel so that the emitted light 300 or 310 is emitted in a direction perpendicular to the surface of the cover substrate CP. Therefore, it is preferable that the outgoing light element GHOE is arranged in a region irradiated with the outgoing light 300 or 310 on the lower surface of the cover substrate CP and has an area larger than the area irradiated with the outgoing light 300 or 310 Do.

The light-emitting element GHOE and the light-receiving element CHOE can be arranged on the same plane. Considering the manufacturing process, it is preferable to form the regions of the light-emitting element (GHOE) and the light-receiving element (CHOE) separately on one film. It is preferable that the light-outgoing element (GHOE) and the light-incoming element (CHOE) are optical elements including a holographic pattern. For example, after a master film having a pattern of an outgoing element (GHOE) and a master film having a pattern of an incident element (CHOE) are arranged at proper positions, two holographic patterns can be simultaneously copied to one holographic recording film .

Hereinafter, a specific operation process for image detection in the directional light substrate (SLS) according to the present invention will be described. The incident light 100 is switched to the scanning light 200 or 210 by the entrance element CHOE. The scanning lights 200 and 210 satisfy the total reflection condition on the upper surface of the cover substrate CP and are incident into the cover substrate CP. For example, the light-incident element CHOE is formed between the first scanning light 200 having the first incident angle? 1 and the second scanning light 210 having the second incident angle? 2 on the XZ plane, The diffused light is converted into diffused light within the range of. It is preferable that the first incident angle 1 and the second incident angle 2 be larger than a total reflection critical angle T _{CP_AIR} between the cover substrate CP and the air layer AIR.

The first scanning light 200 advances to the boundary line closest to the light source LS in the sensing area SA. The second scanning light 210 travels to a boundary line that is farthest from the light source LS in the sensing area SA. The first incidence angle? 1 of the first scanning light 200 and the second incidence angle? 2 of the second scanning light 210 satisfy the total reflection condition on the upper surface of the cover substrate CP. For example, the first incident angle? 1 may have a value of 75 to 80 degrees. The second incident angle [theta] 2 may have a value between 82 degrees and 87 degrees. In particular, the vertical diffusion angle [theta], which is an angle between the first incident angle [theta] 1 and the second incident angle [theta] 2, may have a value between 2 degrees and 12 degrees. Most preferably, the vertical diffusion angle [theta] has a value of about 7 degrees.

It is preferable that the first scanning light 200 and the second scanning light 210 have a horizontal diffusion angle? In an XY plane (or a 'horizontal plane') composed of a longitudinal axis and a longitudinal axis. The range of the horizontal diffusion angle? And the vertical diffusion angle? Is a diffusion angle defining the sensing area SA. The horizontal diffusion angle () can determine the horizontal width range of the sensing area SA. For example, the horizontal diffusion angle? May have a value between 30 degrees and 60 degrees. The sensing area SA is determined by the vertical diffusion angle [theta], the horizontal diffusion angle [phi], the thickness of the cover substrate CP, and the like.

The first scanning light 200 and the second scanning light 210 are totally reflected from the upper surface of the cover substrate CP and become the first outgoing light 300 and the second outgoing light 310 traveling to the lower surface. At this time, the first reflection angle of the first outgoing light 300 is the same as the first reflection angle? 1. Similarly, the second reflection angle of the second outgoing light 310 is the same as the second incident angle 2. The entire area where the first outgoing light 300 and the second outgoing light 310 reach the lower surface of the cover substrate CP corresponds to the sensor area SEA (or the detecting element area). Here, the sensor region SEA corresponds to the region where the detection elements are arranged.

It is preferable that the light exiting element GHOE is disposed corresponding to the sensor area SEA. The first outgoing light 300 and the second outgoing light 310 totally reflected on the upper surface of the cover substrate CP have a refractive index larger than that of air on the lower surface of the cover substrate CP even if there is no outgoing element GHOE If a substrate or film is present, it can be exposed to the outside. However, since the first outgoing light 300 and the second outgoing light 310 have the reflection angle and the incident angle that satisfy the total reflection condition, a large amount of light is reflected into the cover substrate CP. As a result, the intensity of the detection light is lowered and the detection capability is lowered. Therefore, it is preferable that an outgoing light element (GHOE) for transmitting all of the outgoing lights 300 and 310 to the optical sensor is disposed. In particular, the outgoing element GHOE refracts the first outgoing light 300 having the reflection angle? 1 and the second outgoing light 310 having the reflection angle? 2 in the direction perpendicular to the lower surface of the cover substrate CP, Is a holographic optical element.

The size of the sensor area SEA is determined by the first outgoing light 300 and the second outgoing light 310. The sensor region SEA may have a shape continuously extended from the light-incoming element CHOE through the sensing region SA. Therefore, the sensor region SEA has a shape diffused more than the sensing region SA. It is preferable that the light exiting element (GHOE) has a larger size than the sensor area (SEA).

The outgoing light element GHOE transmits the first outgoing light 300 and the second outgoing light 310 to the first detection light 400 and the second detection light 410 which are emitted to the outside of the lower surface of the cover substrate CP, . The first detection light 400 and the second detection light 410 are provided on the lower surface of the directional light substrate SLS to the detection element attached corresponding to the light exiting element GHOE. The image of the object disposed on the upper surface of the cover substrate CP can be detected by recognizing the first detection light 400 and the second detection light 410 emitted to the detection element disposed on the lower surface of the directional light substrate SLS, Can be determined.

Hereinafter, an image recognition apparatus using the directional light unit described in Fig. 1 will be described. Particularly, a flat panel display device incorporating a fingerprint recognition sensor will be described. 2 is a view showing the structure of an optical image sensor built-in type flat panel display device including a directional optical unit and an optical recognition sensor according to a preferred embodiment of the present invention.

Referring to FIG. 2, an optical image sensor built-in type flat panel display device according to a preferred embodiment of the present invention includes a display panel DP, a directional light substrate SLS, and a light source LS. A display area AA and a non-display area NA are defined in the display panel DP. The display area AA occupies most of the central portion of the display panel DP, and the non-display area NA is arranged around the display area. In the display area AA, elements for displaying images to be displayed by the display panel DP are arranged. In the non-display area NA, elements for driving the elements arranged in the display area are arranged.

In particular, in the display area AA, a plurality of pixel areas for displaying an image are arranged in a matrix manner. In this pixel region, one optical sensor for image recognition is arranged. In some cases, a plurality of pixel regions may be arranged as a basic unit, one by one. For example, an optical sensor can be arranged for every 2x2, 3x3 or 4x4 pixels.

The directional light substrate SLS is a thin and wide plate-like substrate having a constant length, a constant width, and a constant thickness. Preferably, the length and width of the directional light substrate SLS have a size sufficient to accommodate the display panel DP. In particular, it is desirable that the size of the display panel DP is slightly larger than the total size of the display panel DP. It is preferable to have at least a portion extended to one side of at least the display panel DP. For example, a light source LS is disposed at a portion further extended to one side of the display panel DP.

The directional light substrates SLS may be surface-bonded to the upper surface of the display panel DP. As described above, the directional light substrate SLS includes a cover substrate CP, a light incident element CHOE, and an outgoing element GHOE. It is preferable that the light exiting element (GHOE) is surface-bonded to the upper surface of the display panel (DP). Here, the upper surface of the display panel DP refers to a surface on which image information provided by the display panel DP is emitted. That is, it refers to the surface of the display panel DP when the user views the image.

As described above, in the directional light substrate SLS, the image detection light 400, 410 is provided to the lower surface, that is, the upper surface of the display panel DP. Then, the optical sensor of the display panel DP disposed under the directional light substrate SLS recognizes the detection light 400, 410. As a result, an image of an object contacting the upper surface of the directional light substrate SLS can be recognized.

More specifically, the scanning light 200 and 210 produced by the light-incident element CHOE of the directional light substrate SLS reach the upper surface of the cover substrate CP. Particularly, when the image object IM is in contact with the cover substrate CP, the scintillation light 200 and 210, which are not in contact with the object IM, are totally reflected and output to the outgoing lights 300 and 310, Is provided as a display panel (DP) as light (400, 410). On the other hand, the scanning light 201, 211, which reaches the portion where the object IM touches the surface of the cover substrate CP, is refracted outward. The scanning light 201 and 211 are refracted toward the object IM without being totally reflected at a portion where the object IM having a refractive index larger than air comes into contact with the cover substrate CP. That is, in the portion where the image object IM exists, the scanning light 201 and 211 are absorbed light 500 and 510, and the amount of light provided to the optical sensor of the display panel DP is almost zero.

As a result, only the detection lights 400 and 410 among the scanning lights 200 and 210 are recognized on the display panel DP, and the absorbed lights 500 and 510 can not be recognized. As described above, the optical sensors of the display panel DP reproduce the pattern of the image by recognizing the reflection pattern of the detection light 400, 410 which is reflected from the surface of the cover substrate CP and adjusted in the vertical direction .

When the directional light unit is applied to a fingerprint recognition apparatus, the image object IM becomes a finger of a person. Then, the ridge portion of the fingerprint contacts the surface of the cover substrate CP, and the valley portion does not contact the surface of the cover substrate CP. Scanning light beams 200 and 210 irradiated with a valley portion are totally reflected to become outgoing lights 300 and 310. [ On the other hand, the inter-scanning light 201 and 211 are refracted into the protuberance (R) portion and become the absorbed light 500 and 510 that escape to the outside of the cover substrate CP.

The image sensing on the XY plane will be described with further reference to the perspective view shown at the bottom of FIG. The incident light 100 may include collimated infrared rays having a constant cross-sectional area. For this purpose, the light source LS may be one that provides an infrared laser.

The incident light 100 is converted into scanning light 200 and 210 by the light-incident element CHOE. At this time, the progressive lights 200 and 210 are converted to have the horizontal diffusion angle? In the XY plane, which is a horizontal plane made up of the X axis as the longitudinal axis and the Y axis as the lateral axis. In the XZ plane, which is a vertical plane made up of the longitudinal axis X and the thickness direction Z axis, it is converted to have a vertical diffusion angle?.

Here, the sensing region SA is defined on the upper surface of the cover substrate CP by the horizontal diffusion angle? And the vertical diffusion angle?. For example, the image sensing area SA may be determined as a trapezoidal rectangular inner area, such as a hatched area in FIG.

≪ First application example >

Up to now, the present invention has been described centering on a directional light unit for providing a directional light in a flat panel display device incorporating an optical image sensor. Hereinafter, specific application examples of optical image sensor built-in flat panel display devices formed by combining the directive optical unit according to the present invention with a flat panel display panel including an optical recognition sensor will be described.

Hereinafter, a flat panel display device incorporating an optical image sensor according to a first application example of the present invention will be described with reference to FIG. 3 is a cross-sectional view showing the structure of an optical image sensor built-in type liquid crystal display device including a directional light unit and an optical recognition sensor according to a first application example of the present invention.

An optical image sensor built-in type liquid crystal display device according to a first application example of the present invention includes a liquid crystal display panel (LCP), a directional light substrate (SLS), and a light source (LS). The liquid crystal display panel LCP includes a lower substrate SL and an upper substrate SU and a liquid crystal layer LC interposed therebetween. In the lower substrate SL, a plurality of pixel regions are arranged in a matrix manner. Color filters may be arranged on the upper substrate SU corresponding to the pixel regions. Alternatively, the upper substrate SU may be a substrate on which special elements are not formed. Here, the liquid crystal display panel LCP has a horizontal electric field type. However, the present invention is not limited to this, and can be applied to various liquid crystal display panels.

A pixel electrode (PXL) and a common electrode (COM) for representing an image may be disposed in the pixel region. Further, a thin film transistor T for selectively applying an image signal to the pixel electrode PXL is disposed. The optical sensor TS may be disposed adjacent to the thin film transistor T. [ One or more optical sensors TS may be arranged for each pixel region. Or one optical sensor TS may be disposed for each of the plurality of pixel regions.

On the upper surface of the upper substrate (SU) of the liquid crystal display panel (LCP), the directional light substrate (SLS) described in the embodiments of the present invention is attached. The directional light substrate SLS includes a cover substrate CP, an incident element CHOE, and an exit element GHOE. The directional light substrate SLS is surface-bonded to the upper surface of the upper substrate SU via an optical adhesive layer SDH.

The liquid crystal display panel (LCP) is a non-self-luminous display device which can not emit light by itself. In this case, the backlight unit BLU may be disposed on the lower surface of the lower substrate SL. A light source LS may be disposed on one side of the backlight unit BLU so as to face the light incident element CHOE. In this case, the light source LS can be formed integrally with the backlight unit BLU. Alternatively, the light source LS may be manufactured in a different configuration and disposed near the backlight unit BLU.

The liquid crystal display panel LCP includes a display area AA and a non-display area NA. The light exiting element GHOE of the directional light substrate SLS is disposed in the display area AA. The light-incident element CHOE is disposed in the non-display area NA. Further, the light source LS is also arranged opposite to the light-incoming element CHOE in the non-display area NA.

In particular, it is preferable that an optical sensor TS is disposed under the light-exiting element (GHOE). For example, the optical sensor TS can be disposed with a uniform distribution density in all regions in the liquid crystal display panel (LCP). As another example, the optical sensor TS may be selectively disposed only in a portion corresponding to the light-outgoing element (GHOE) in the liquid crystal display panel (LCP).

≪ Second application example >

Hereinafter, a flat panel display device incorporating an optical image sensor according to a second application example of the present invention will be described with reference to FIG. 4 is a cross-sectional view illustrating a structure of an organic light emitting diode display device with an optical image sensor including a directional light unit and an optical recognition sensor according to a second application example of the present invention.

An optical image sensor built-in organic light emitting diode display device according to a second application example of the present invention includes an organic light emitting diode display panel (OLP), a directional light substrate (SLS), and a light source (LS). In the organic light emitting diode display panel OLP, the substrate SUB on which the display elements are disposed and the in cap (ENC) for protecting the display element are bonded together. In the substrate SUB, a plurality of pixel regions are arranged in a matrix manner. The in-cap (ENC) may have color filters arranged corresponding to the pixel regions. Alternatively, the in-cap (ENC) may be a transparent substrate on which no special elements are formed. Here, the case of the top emission organic light emitting diode display panel OLP is shown. However, the present invention is not limited to this, and various types of structures such as a top emission type can be applied.

In the pixel region, an organic light emitting diode (OLE) for displaying an image and a thin film transistor (T) for selectively applying an image signal to the organic light emitting diode (OLE) are arranged. The organic light emitting diode includes an anode electrode ANO, an organic light emitting layer OL, and a cathode electrode CAT. The optical sensor TS may be disposed adjacent to the thin film transistor T. [ One or more optical sensors TS may be arranged for each pixel region. Or one optical sensor TS may be disposed for each of the plurality of pixel regions.

On the upper surface of the in-cap (ENC) of the organic light emitting diode display panel (OLP), the directional light substrate (SLS) described in the embodiments of the present invention is attached. The directional light substrate SLS includes a cover substrate CP, an incident element CHOE, and an exit element GHOE. The directional light substrate SLS is surface-attached to the upper surface of the in-cap ENC via the optical adhesive layer SDH.

The organic light emitting diode display panel (OLP) is a self-luminous display device that emits light by itself. In this case, a separate backlight unit (BLU) is not required. Therefore, it is preferable to arrange the light source LS so as to face the light-incoming element CHOE on one side of the organic light emitting diode display panel OLP.

More specifically, the organic light emitting diode display panel OLP includes a display area AA and a non-display area NA. The directional light substrate SLS is preferably configured to have a larger size than the organic light emitting diode display panel OLP. The light exiting element GHOE of the directional light substrate SLS is disposed in the display area AA. The light-incident element CHOE is disposed above the extended space on the side of the organic light emitting diode display panel OLP. And the light source LS can be disposed under the expanded space.

As described above, the display device incorporating the optical image recognition sensor according to the present invention includes the cover substrate attached to the outer surface of the display device and the ultra-thin holography film attached to only one surface of the cover substrate. Therefore, the optical image recognition sensor can be incorporated without affecting the thickness of the display device. In addition, since the highly collimated light can be uniformly distributed (or scanned) in the entire area of the display panel of the display device, the image can be recognized. Therefore, the image recognition resolution is excellent and the fine image can be accurately recognized .

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification, but should be defined by the claims.

DP: display panel SLS: directional light substrate
CP: Cover substrate CHOE: Light-incident element
GHOE: Exposure element LS: Light source
100: incident light 200, 210, 201, 211: scanning light
300, 310: Outgoing light 400, 410: Detection light
500, 510: absorption light SA: (image) sensing area
SEA: Sensor (detection element) area

Claims (9)

A display panel in which a display area and a non-display area are defined; And
A directional light unit attached to an upper surface of the display panel, the directional light unit having a length, a width, and a constant thickness to receive the display panel,
The directional light unit includes:
A cover substrate having an area corresponding to the length and the width;
An outgoing light element disposed in the display area on a lower surface of the cover substrate;
An incident-light element disposed on the non-display area on a lower surface of the cover substrate; And
And a light source arranged to face the light-incident element at the one side of the display panel.
The method according to claim 1,
Wherein the light source provides incident light at an incident point defined on a surface of the light-incident element;
Wherein the light incident element has a holographic pattern for converting the incident light into scanning light having a diffusing angle for totally reflecting the incident light on the surface of the cover substrate and entering the inside of the cover substrate;
Wherein the outgoing light element includes an image recognition sensor built-in flat panel display having a holographic pattern for switching the outgoing light totally reflected from the upper surface of the cover substrate by the scanning light to detection light emitted in a direction perpendicular to the lower surface of the cover substrate Device.
3. The method of claim 2,
The diffusion angle
A horizontal diffusion angle that is an angle of diffusion on the horizontal plane of the cover substrate in the longitudinal direction and the width direction; And
And a vertical diffusion angle which is an angle of diffusion on a vertical plane formed by the longitudinal direction and the thickness direction of the cover substrate.
The method of claim 3,
The scanning light,
Wherein the light is diffused between the first scanning light having the first incident angle on the vertical plane and the second scanning light having the second incident angle on the vertical plane.
5. The method of claim 4,
In the outgoing light,
An image recognition sensor built-in flat panel display in which the first scanning light is diffused between the first outgoing light totally reflected from the upper surface of the cover substrate and the second outgoing light which is reflected from the upper surface of the cover substrate by the second scanning light, Device.
6. The method of claim 5,
The detection light,
An image recognition sensor built-in type in which the first outgoing light is emitted to the outside of the cover substrate between the first detection light refracted by the outgoing light element and the second outgoing light is refracted by the outgoing element, Flat panel display.
3. The method of claim 2,
A range of the upper surface of the cover substrate to which the scanning light is irradiated is defined as a sensing area for positioning an image object to be recognized;
Wherein the range in which the detection light is emitted is defined as a sensor area in which the optical sensor is disposed.
The method according to claim 1,
Wherein the display panel and the directional light substrate are arranged such that,
Flat panel display with built - in image recognition sensor bonded by optical adhesive.
The method according to claim 1,
The light source includes:
An image recognition sensor built-in flat panel display device that provides collimated light having a domed sectional shape.

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