JP6796751B2 - Light source device and projection type image display device - Google Patents

Description

The present disclosure relates to a projection type image display device using a light source device including a light source that emits blue excitation light and a light emitting body that emits light in response to the excitation light.

Patent Document 1 provides a blue laser light emitter as an excitation light source, diffuses the emitted light from the excitation light source by a diffuser plate, and uses the diffused light as a light source light in the blue wavelength band. A projector capable of projecting a high-quality color image by providing a light source device having a wide wavelength distribution in the light source light is disclosed.

Japanese Unexamined Patent Publication No. 2011-128521

The present disclosure provides a projection type image display device including a light source device capable of optimizing the chromaticity of blue component light.

The light source device of the present disclosure includes a solid-state light source that emits blue light in a first wavelength band having a first polarization, blue light of the first polarization, and blue light of a second polarization different from the first polarization. A substrate provided with a dichroic mirror that reflects one of light and other colored light and transmits the other, and a segment provided with a first phosphor that is excited by the blue light reflected or transmitted by the dichroic mirror. By providing a phosphor wheel, a wavelength selection reflector that reflects a part of blue light and transmits the remaining blue light and other colored light, and a dichroic mirror and a substrate, and transmitting the light back and forth. A retardation plate that converts the first polarization into the second polarization, and a second fluorescence that emits light emitted from a second wavelength band that is on the longer wavelength side than the first wavelength band and is adjacent to the first wavelength band. The fluorescent plate provided with the body and the blue light transmitted by the wavelength selective reflector are condensed to excite the second phosphor of the fluorescent plate, and the colored light emitted from the second phosphor is condensed to perform wavelength selective reflection. It is provided with a light collecting element that emits light toward the plate.

According to the present disclosure, it is possible to improve the chromaticity of the blue component light displayed on the projection type image display device.

The figure which shows the projection type image display device which includes the light source device in Embodiment 1. The figure which shows the phosphor wheel in Embodiment 1. The figure which shows the principle of color generation in Embodiment 1. The figure which shows the principle of color generation in Embodiment 1. The figure which shows the principle of color generation in Embodiment 1. The figure which shows the color wheel in Embodiment 1. Spectral diagram in the projection type image display device of the first embodiment The figure which shows the chromaticity diagram for demonstrating the effect of Embodiment 1. The figure which shows the main part of the projection type image display device in Embodiment 2. The figure which shows the main part of the projection type image display device in Embodiment 2. The figure which shows the main part of the projection type image display device in Embodiment 2. The figure which shows the main part of the projection type image display device in Embodiment 3.

Hereinafter, embodiments will be described in detail with reference to the drawings as appropriate. However, more detailed explanation than necessary may be omitted. For example, detailed explanations of already well-known matters and duplicate explanations for substantially the same configuration may be omitted. This is to avoid unnecessary redundancy of the following description and to facilitate the understanding of those skilled in the art.

It should be noted that the accompanying drawings and the following description are provided for those skilled in the art to fully understand the present disclosure, and are not intended to limit the subject matter described in the claims.

[Embodiment 1]
(Projection type video display device)
Hereinafter, the configuration of the projection type image display device according to the first embodiment will be described with reference to FIGS. 1 to 6. FIG. 1 is a diagram showing an optical configuration of the projection type image display device 100 according to the first embodiment. In the first embodiment, a case where red component light R, green component light G, blue component light B (blue component light B ₁ + blue component light B ₂ ), and yellow component light Y are used as the image light is illustrated.

As shown in FIG. 1, first, the projection type image display device 100 includes a light source unit 10, a dichroic mirror 20, a phosphor wheel 30, a λ / 4 plate (1/4 wave plate) 40, and a first. It has a two-wavelength band light emitting unit 300, a color wheel 50, a rod integrator 60, a DMD (Digital Mirror Device) 70, and a projection unit 80. Here, the λ / 4 plate 40 is an example of a retardation plate.

The light source unit 10 is composed of a plurality of solid-state light sources such as a laser diode (LD: Laser Diode) and a light emitting diode (LED: Light Emitting Diode), for example. In this embodiment, a laser diode, particularly a laser diode 11 that emits blue light, is used as a solid-state light source.

The light emitted from the light source unit 10 is blue light having a wavelength of 455 nm (blue component light B ₁ ), and this blue light is S-polarized light and is also used as excitation light for exciting a phosphor. However, the wavelength of the light emitted from the light source unit 10 is not limited to 455 nm, and may be, for example, a wavelength of 440 to 460 nm. (This wavelength of 440 to 460 nm is an example of the first wavelength band.)
The blue component light B ₁ emitted from the light source unit 10 passes through the lens 111, the lens 112, and the diffuser plate 141 and is incident on the dichroic mirror 20.

The dichroic mirror 20 reflects S-polarized blue light, but transmits P-polarized blue light and other colored light. The blue component light B ₁ reflected by the dichroic mirror 20 is focused by the lenses 113 and 114 and incident on the phosphor wheel.

As shown in FIG. 2, the phosphor wheel 30 includes a substrate 31, a reflective film 32 formed on the substrate 31, a phosphor film 33 formed by coating on the reflective film 32 in an annular shape, and a phosphor film. It is composed of an antireflection film 34 formed on the 33 and a motor 35 for rotating the substrate 31. In this embodiment, a wavelength selective reflector is used as the substrate 31. In FIG. 2, FIG. 2A is a view of the phosphor wheel viewed in the −x direction of FIG. 1, and FIG. 2B is a view of the phosphor wheel viewed in the z direction of FIG.

As shown in FIG. 2A, the phosphor film 33 is composed of a yellow fluorescent film 33Y and a green fluorescent film 33G. Here, the yellow fluorescent film 33Y and the green fluorescent film 33G are examples of the first phosphor.

The phosphor film 33 can be produced, for example, by adhering a ceramic phosphor to a substrate with an adhesive. Examples of the ceramic phosphor used for the phosphor film 33 include a YAG phosphor and a LAG phosphor, which are active garnet structure phosphors with cerium.

As shown in FIG. 2A, the phosphor wheel 30 is composed of four segments in the circumferential direction. The first segment (angle region θ _R ) is a region for generating the red component light R. The second segment (angle region θ _G ) is a region for generating the green component light G. The third segment (angle region θ _B ) is a region for generating the blue component light B. The fourth segment (angle region θ _Y ) is a region for generating the yellow component light Y.

A yellow phosphor film 33Y is formed in the angle region θ _Y + θ _R. The yellow phosphor film 33Y has a phosphor Y that emits yellow emission light Y in response to the blue component light B ₁ (excitation light) emitted from the light source unit 10. An antireflection film is formed on the yellow phosphor film 33Y. The yellow phosphor film 33Y is a region to which the blue component light B ₁ (excitation light) is irradiated while the phosphor wheel 30 is rotating. In other words, on the yellow phosphor film 33Y, blue component light _{B 1} is being focused by the lens 114.

The angular region theta _G, the green phosphor film 33G is formed. Green phosphor layer 33G has a phosphor G ₁ for emitting green light beam G ₁ in accordance with the blue component light B ₁ emitted from the light source unit 10 _(excitation light). An antireflection film is formed on the green phosphor film 33G. The green phosphor film 33G is a region to which the blue component light B ₁ (excitation light) is irradiated while the phosphor wheel 30 is rotating. In other words, the blue component light B ₁ is focused by the lens 114 on the green phosphor film 33G.

The reflective film 32, the phosphor film 33, and the antireflection film 34 are not formed in the angle region θ _B. The blue component light B ₁ emitted from the light source unit 10 is incident on the substrate 31 in the angle region θ _B. Since the wavelength selection reflector is used as the substrate 31 in this embodiment, the angle region θ _B reflects a part of the incident blue component light B ₁ and transmits the remainder, and also emits light G _2. It is a wavelength selective reflection segment that transmits light. As another method of forming the angle region θ _B into the wavelength selective reflection segment, for example, a metal plate may be used as the substrate 31, a notch may be provided in the angle region θ _B of the substrate 31, and the wavelength selective reflector may be attached. As shown in FIG. 1, the blue component light B ₁ emitted from the light source unit 10 and transmitted through the wavelength selective reflection segment is incident on the second wavelength band light emitting unit 300.

As shown in FIG. 1, the second wavelength band light emitting unit 300 is composed of a lens 312, a mirror 311 and a second wavelength band fluorescent plate 330. As shown in FIG. 3c, the second wavelength band fluorescent plate 330 includes a substrate 331, a reflective film 332 formed on the substrate 331, and a second wavelength band phosphor film 333 coated and formed on the reflective film 332. It is composed of an antireflection film 334 formed on the second wavelength band phosphor film 333. The second wavelength band phosphor film 333 has a phosphor G ₂ which emits emission light G ₂ in the second wavelength band in accordance with the blue component light B ₁ emitted _(excitation light) from the light source unit 10. Here, the phosphor G ₂ is an example of the second phosphor.

Lens 312 and the mirror 311 is configured to condense the blue component light _{B 1} incident on the second wavelength band light emitting unit 300 to the second wavelength band fluorescent plate 330, the emitted light _{G 2} emitted in the second wavelength band fluorescent plate 330 Is focused and emitted toward the substrate 31. Here, the lens 312 and the mirror 311 are examples of a light collecting element.

The mirror 311 is an ellipsoidal mirror provided with one opening in this embodiment. As shown in FIG. 1, of the focus in two points of the mirror 311 (the ellipsoidal mirror), a point close to the opening (point A) is the region where the blue component light B ₁ on the substrate 31 of the phosphor wheel passes The second wavelength band fluorescent plate 330 is located at one point (point B) far from the opening.

Lens 312, out of the emitted luminescent light G ₂ at a point B on the second wavelength band fluorescent plate 330, to emit toward the point A to those toward the opening without being reflected by the mirror 311, the point A It is located between the point B and the point B.

Therefore, the blue component light B ₁ incident on the second wavelength band light emitting unit 300 passes through the point A, a part of it is reflected by the mirror 311 and the rest passes through the lens 312 and is a point on the second wavelength band fluorescent plate 330. It is focused on B. A part of the emitted light G ₂ emitted at the point B is reflected by the mirror 311 and the remainder is focused on the point A through the lens 312 and emitted to the outside of the second wavelength band light emitting unit 300. Will be done.

Next, the principle of color generation in the peripheral portion of the phosphor wheel 30 will be described with reference to FIGS. 3a to 3c.

FIG. 3a shows a case where the blue component light B ₁ (excitation light) is irradiated to any of the angular regions θ _Y , θ _R , and θ _G of the phosphor wheel 30. The blue component light B ₁ (L1) is light emitted from the light source unit 10, and is S-polarized in the present embodiment. The blue component light B ₁ (L1) becomes circularly polarized blue component light B ₁ (L2) by passing through the λ / 4 plate 40. The blue component light B ₁ (L2) passes through the antireflection film 34 and becomes the blue component light B ₁ (L3). Due to the effect of the antireflection film 34, the light intensity of the blue component light B ₁ (L3) is 95% or more of the light intensity of the blue component light B ₁ (L2). The yellow phosphor film 33Y or the green phosphor film 33G emits emission light Y or emission light G ₁ when the blue component light B ₁ (L3) is irradiated. Emitting light Y and emitting light G ₁ is emitted to the full 360 ° -direction, the light emitted toward the substrate 31 is reflected by the reflection film 32. Therefore, the emitted light Y and the emitted light G ₁ are emitted in the direction opposite to the traveling direction of the blue component light B ₁ (L3). Since the emitted light Y and the emitted light G ₁ are fluorescent light, they are unpolarized, and even if they pass through the λ / 4 plate 40, they are unpolarized.

FIG. 3b shows a case where the blue component light B ₁ (excitation light) is applied to the angle region θ _B of the phosphor wheel 30. The blue component light B ₁ (L1) is light emitted from the light source unit 10, and is S-polarized in this embodiment. The blue component light B ₁ (L1) becomes circularly polarized blue component light B ₁ (L2) by passing through the λ / 4 plate 40. The blue component light B ₁ (L2) is transmitted by 35% of the substrate 31 which is a wavelength selection reflector, becomes blue component light B ₁ (L2'), and is incident on the second wavelength band light emitting unit 300. The remaining 65% is reflected and becomes blue component light B ₁ (L4). The substrate 31 also transmits the emitted light G ₂ . That is, the substrate 31 transmits (65%) 35% of the light in the wavelength band (455 nm) of the blue component light B ₁ and transmits the light in the wavelength band (460 to 750 nm) of the emitted light G ₂ . Since the emitted light G ₂ is fluorescent light, it is unpolarized, and even if it passes through the λ / 4 plate 40, it is unpolarized. Further, the blue component light B ₁ (L4) is circularly polarized like the blue component light B ₁ (L2), and by passing through the λ / 4 plate 40 again, the blue component light B ₁ (L5) of P polarization is obtained. )become. The transmittance of the substrate 31 should be adjusted as necessary, and may be in the range of 10 to 60%. Here, the wavelength band of 460 nm to 750 nm, which is the wavelength band of the emitted light G ₂ , is an example of the second wavelength band.

The blue component light B ₁ (L2') incident on the second wavelength band light emitting unit 300 is irradiated to the second wavelength band fluorescent plate as shown in FIG. 3c, and the blue component light B ₁ (L2) shown in FIG. 3a. Behaves in the same way as. That is, the blue component light B ₁ (L2') passes through the antireflection film 334 and becomes the blue component light B ₁ (L3'). Due to the effect of the antireflection film 334, the light intensity of the blue component light B ₁ (L3') is 95% or more of the light intensity of the blue component light B ₁ (L2'). When the second wavelength band fluorescent film is irradiated with the blue component light B ₁ (L3'), the emitted light G ₂ is emitted. The emitted light G ₂ is emitted in all directions of 360 °, and the light emitted in the direction toward the substrate 331 is reflected by the reflective film 332. Therefore, the emitted light G ₂ is emitted in the direction opposite to the traveling direction of the blue component light B ₁ (L3'). Since the emitted light G ₂ is fluorescent light, it is unpolarized, and even if it passes through the λ / 4 plate 40, it is unpolarized.

As described above, the light generated by the phosphor wheel 30 and emitted through the λ / 4 plate 40 and the dichroic mirror 20 is emitted light Y and the angle region θ _{G in the} angle region θ _Y + θ _{R as} it rotates. In the light emitting light G ₁ and in the angle region θ _B , the light is a composite light of the blue component light B ₁ (L5) and the light emitting light G ₂ .

The light emitted from the dichroic mirror 20 passes through the lens 131, the optical path is bent in the direction perpendicular to the mirror 124, passes through the lens 132, and enters the color wheel 50.

As shown in FIG. 4, the color wheel 50 is composed of a transparent substrate 51, a dielectric multilayer film 52 formed on the substrate 51, and a motor 53 for rotating the substrate 51. In FIG. 4, FIG. 4A is a view of the color wheel 50 viewed in the z direction of FIG. 1, and FIG. 4B is a view of the color wheel 50 viewed in the y direction of FIG. The dielectric multilayer film 52 is formed in a predetermined angle region θ _R , a red transmission dichroic film 52 _R formed in a predetermined angle region θ _R , a green transmission dichroic film 52 _G formed in a predetermined angle region θ _G , and a predetermined angle region θ _B. It is composed of a blue transmissive dichroic film 52B and an antireflection film 52C formed in a predetermined angle region θ _Y.

The color wheel 50 is controlled so that the rotation is synchronized with the phosphor wheel 30. That is, at the timing when the light is emitted from the angle region θ _R of the phosphor wheel 30, the light is incident on the angle region θ _R of the color wheel 50. At the timing when the light is emitted from the angle region θ _G of the phosphor wheel 30, the light is incident on the angle region θ _G of the color wheel 50. At the timing when the light is emitted from the angle region θ _B of the phosphor wheel 30, the light is incident on the angle region θ _B of the color wheel 50. At the timing when the light is emitted from the angle region θ _Y of the phosphor wheel 30, the light is incident on the angle region θ _Y of the color wheel 50.

As described above, the light generated by the phosphor wheel 30 and the color wheel 50 is emitted in time divisions in the angle regions θ _R , θ _G , θ _B , and θ _Y. That is, each color component light including red component light, green component light, blue component light, and yellow component light is generated by the phosphor wheel 30 and the color wheel 50 and emitted in a time-divided manner.

The color generation in each angle region will be described below with reference to the spectrum shown in FIG.

In angular region theta _R, emitted light Y (FIG. 5 (a)) is emitted from the yellow phosphor film 33Y of the phosphor wheel 30, by passing through the red transmission dichroic film 52R of the color wheel 50, the red component light It becomes R (FIG. 5 (a)). By adjusting the spectral characteristics of the red transmission dichroic film 52R of the color wheel 50, the color purity of the red component light R can be adjusted.

In the angle region θ _G , the emitted light G ₁ (FIG. 5 (b)) is emitted from the green phosphor film 33 _G of the phosphor wheel 30, and is transmitted through the green transmissive dichroic film 52 G of the color wheel 50 to form a green component. It becomes light G (FIG. 5 (b)). By adjusting the spectral characteristics of the green transmissive dichroic film 52G of the color wheel 50, the color purity of the green component light G can be adjusted.

In the angle region θ _B , the blue component light B ₁ reflected by the substrate 31 (wavelength selective reflector) of the phosphor wheel 30 and the second wavelength band fluorescent plate 330 of the second wavelength band light emitting unit 300 emit fluorescence. The luminescent light G ₂ (the luminescent light G ₂ includes the blue component light B ₂ ) transmitted through the substrate 31 (wavelength selective reflecting plate) of the body wheel 30 is synthesized and transmitted through the blue transmissive dichroic film 52B of the color wheel 50. As a result, it becomes blue component light B (blue component light B ₁ + blue component light B ₂ ). Blue light transmission dichroic film 52B is configured to transmit the blue component light B _1, by passing through a short wavelength side of the emission light G _2, to extract the blue component light B _2. The blue component light B ₂ is adjusted to the optimum blue chromaticity by mixing with the blue component light B ₁ having a wavelength of 455 nm.

In this embodiment, the wavelength band of the emitted light G ₂ is 460 nm to 750 nm, and the main wavelength of the blue component light B ₂ is 515 nm, but the wavelength band is not limited thereto. It is desirable to select the phosphor G ₂ and design the spectral characteristics of the blue transmissive dichroic film 52B so that the main wavelength of the blue component light B ₂ is within the range of 470 to 530 nm. In FIG. 5C, the scale of the blue component light B ₁ is 1/100.

In the angular region θ _Y , the emitted light Y is emitted from the yellow phosphor film 33Y of the phosphor wheel 30, and passes through the antireflection film 52C of the color wheel 50 to become the yellow component light Y. The color change caused by the emitted light Y passing through the antireflection film 52C of the color wheel 50 is at a negligible level.

The light emitted from the color wheel 50 is incident on the rod integrator 60. The rod integrator 60 is a solid rod made of a transparent member such as glass. The rod integrator 60 equalizes the light emitted from the light source unit 10 and the light emitted from the phosphor wheel 30. The rod integrator 60 may be a hollow rod whose inner wall is formed of a mirror surface.

The light emitted from the rod integrator 60 passes through the lens 151, the lens 152, and the lens 153, is incident on the total reflection prism composed of the triangular prism 161 and the triangular prism 162, and then is incident on the DMD 70.

The DMD 70 is a light modulation element that modulates each color component light generated by the light source unit 10, the phosphor wheel 30, and the color wheel 50 in a time-divided manner. Specifically, the DMD 70 is composed of a plurality of micromirrors, and the plurality of micromirrors are movable. Each micromirror basically corresponds to one pixel. The DMD 70 switches whether or not to reflect light to the projection unit 80 side by a modulation operation that changes the angle of each minute mirror according to the video signal. The DMD 70 expresses the gradation of each color corresponding to the angle regions θ _R , θ _G , θ _B , and θ _Y described with reference to FIGS. 2 and 4. That is, the red component light R (video light) is modulated during the time when the angle region θ _R is irradiated with light. During the time when the angle region θ _G is irradiated with light, the green component light G (video light) is modulated. During the time when the angle region θ _B is irradiated with light, the blue component light B (video light) is modulated. During the time when the angle region θ _Y is irradiated with light, the yellow component light Y (image light) is modulated.

The video light modulated by the DMD 70 passes through the triangular prisms 161 and 162 and is incident on the projection unit 80. The image light incident on the projection unit 80 is magnified and projected onto a screen (not shown).

FIG. 6 shows a chromaticity diagram, and as shown in this chromaticity diagram, the color gamut A of the projection type image display device 100 of the present embodiment includes sRGB (only each color point is shown in the figure). You can see that. The chromaticity of the blue component light B ₂ is a point indicated by a triangle in the figure, and the appropriate blue chromaticity is obtained by mixing with the blue component light B ₁ . On the other hand, it can be seen that the color gamut B when only the blue component light B ₁ is used as the image light without using the blue component light B ₂ has a region that does not include sRGB.

(Action and effect)
In the first embodiment, the phosphor wheel 30 is provided with a wavelength selective reflection segment, and the blue component light B ₁ transmitted through the wavelength selective reflection segment is converted into light emission G ₂ by the second wavelength band light emission unit 300. the blue component light B ₁ can be mixed with the blue component light B _2, the color gamut including sRGB that could not be included in the blue component light B ₁ is made feasible.

[Embodiment 2]
In this embodiment, the main part 200 of the projection type image display device 100 of FIG. 1 has the form shown in FIG. 7a. In the first embodiment, the dichroic mirror 20 reflected the blue component light B ₁ (S polarized light) emitted from the light source unit 10, and the blue component light B ₁ (P polarized light) and the unpolarized light were transmitted. On the other hand, the dichroic mirror 20'used in this embodiment transmits the blue component light B ₁ (S polarized light) emitted from the light source unit 10, and reflects the blue component light B ₁ (P polarized light) and the unpolarized light. To do.

Further, in the first embodiment, the mirror 311 is an ellipsoidal mirror, whereas in the present embodiment, the mirror 311 is a parabolic mirror. Lens 312, of the emitted light G ₂ emitted at a point B on the second wavelength band fluorescent plate 330, to the ones of the angle does not hit the mirror 311 into parallel light, located between the points A and B I have to. Further, a lens 313 and a lens 314 are added as a condensing element of the second wavelength band light emitting unit 300, and the blue component light B ₁ incident on the second wavelength band light emitting unit 300 through the point A is a lens. The 313 and the lens 314 produce parallel light.

Further, in the first embodiment, the wavelength selective reflector is used as the substrate 31 of the phosphor wheel 30, but in this embodiment, the wavelength selective reflector 320 is provided separately from the substrate 31, and the lens 314 and the lens are provided. It is located between 312. The substrate 31 is a transparent plate or a metal plate in which the angle region θ _B is notched. Point B is the focal point of the mirror 311 and the second wavelength band fluorescent plate 330 is located.

The blue component light B ₁ , which becomes parallel light by passing through the lens 313 and the lens 314, is incident on the wavelength selection reflector 320, and a part of the light is transmitted and the remainder is reflected, and the blue component light B ₁ is passed through the lens 314 and the lens 313 to the point A. Return to. A part of the blue component light B ₁ transmitted through the wavelength selection reflector 320 is reflected by the mirror 311 and the rest is focused on the point B on the second wavelength band fluorescent plate 330 through the lens 312. A part of the emitted light G ₂ emitted at the point B is reflected by the mirror 311 and the remainder becomes parallel light by passing through the lens 312 and is condensed to the point A through the lens 313 and the lens 314. As a result, it is emitted to the outside of the second wavelength band light emitting unit 300.

Some of the parallel light in the second wavelength band light emitting unit 300 becomes light (L6) that is reflected by the mirror 311 at a position closer to the apex of the mirror 311 than the second wavelength band fluorescent plate 330 and heads toward the point B. Since some of them are transparent, the substrate 331 is a transparent plate, and the reflective film 332 in the first embodiment shown in FIG. 3c is replaced with the first wavelength band transmissive dichroic film 335 as shown in FIG. 7b in this embodiment. ing. The first wavelength band transmission dichroic film 335 transmits the blue component light B ₁ and reflects the emitted light G ₂ . Here, the reason why the first wavelength band transmission dichroic film 335 is used is that if an antireflection film that also transmits the emitted light G ₂ is used instead, the second wavelength band phosphor film of the emitted light G ₂ is transferred to the substrate 331. As shown in FIG. 7c, the light emitted in the heading direction is reflected at a position closer to the apex than the second wavelength band fluorescent plate of the mirror 311 to become parallel light, and a part of the light is incident on the lens 312 and is parallel light. This is because the efficiency of the optical system is lowered because the light is not focused on the point A. Here, the mirror 311 and the lenses 312, 313, and 314 are examples of the condensing element.

[Embodiment 3]
In this embodiment, as shown in FIG. 8, only a lens is used as a condensing element of the second wavelength band light emitting unit 300 without using a mirror. The lens 315 has the same shape as the lens 314, and the lens 316 has the same shape as the lens 313. The wavelength selection reflector 320 is located between the lens 314 and the lens 315, and the substrate 31 is a transparent plate or a metal plate in which the angle region θ _B is notched as in the second embodiment. .. The second wavelength band fluorescent plate has the same configuration as shown in FIG. 3c as in the first embodiment.

The blue component light B ₁ incident on the second wavelength band light emitting unit 300 through the point A becomes parallel light by passing through the lens 313 and the lens 314, and is incident on the wavelength selection reflector 320. The blue component light B ₁ incident on the wavelength selection reflector 320 is partially transmitted and the remainder is reflected and returns to the point A through the lens 314 and the lens 313. The blue component light B ₁ transmitted through the wavelength selection reflector 320 is focused on the point B on the second wavelength band fluorescent plate 330 by the lens 315 and the lens 316. The emitted light G ₂ emitted at the point B becomes parallel light by passing through the lens 315 and the lens 316, and is condensed to the point A through the wavelength selection reflector 320, the lens 313, and the lens 314. It is emitted to the outside of the two-wavelength band light emitting unit 300. Lenses 313 to 316 are examples of condensing elements.

[Other embodiments]
As described above, Embodiments 1, 2 and 3 have been described as examples of the techniques disclosed in this application. However, the technique in the present disclosure is not limited to this, and can be applied to embodiments in which changes, replacements, additions, omissions, etc. are made. It is also possible to combine the components described in the first, second, and third embodiments to form a new embodiment.

Therefore, other embodiments will be illustrated below.

In the embodiment, the DMD 70 is exemplified as the light modulation element, but the embodiment is not limited to this. The light modulation element may be one liquid crystal panel or three liquid crystal panels (red liquid crystal panel, green liquid crystal panel and blue liquid crystal panel). The liquid crystal panel may be a transmissive type or a reflective type.

In the embodiment, while transmitting blue component light B _1, the blue light transmission dichroic film to extract the blue component light B ₂ from the emitted light G ₂ by passing through the short wavelength side of the emission light G ₂ is, color wheel Although if it is formed as a blue light transmission dichroic film 52B has been exemplified in the 50 angular field theta _B, the embodiment is not limited thereto. The blue transmissive dichroic film may be formed in the angle region θ _B of the phosphor wheel 30, may be formed on the second wavelength band fluorescent plate 330, or may be formed on the wavelength selective reflector 320. Is also good.

In the first embodiment, the blue component light emitted from the light source unit 10 is the P-polarized blue component light, and the blue component light emitted from the phosphor wheel 30 and transmitted through the λ / 4 plate 40 is S-polarized light. As a result, the dichroic mirror 20 may have a characteristic of transmitting S-polarized light and reflecting P-polarized light.

Further, in the second and third embodiments, the blue component light emitted from the light source unit 10 is used as the blue component light of P-polarized light, and the blue emitted from the phosphor wheel 30 and transmitted through the λ / 4 plate 40. A dichroic mirror 20 having a characteristic of reflecting S-polarized light and transmitting P-polarized light may be used so that the component light becomes S-polarized light.

Since the above-described embodiment is for exemplifying the technique in the present disclosure, various changes, replacements, additions, omissions, etc. can be made within the scope of claims or the equivalent scope thereof.

The present disclosure can be applied to a projection type image display device such as a projector.

10 Light source unit 11 Laser diode 20, 20'Dichroic mirror 30 Fluorescent wheel 31 Substrate 32 Reflective film 33 Fluorescent film 33Y Yellow phosphor film 33G Green phosphor film 34 Antireflection film 35, 53 Motor 40 λ / 4 board 50 Color Wheel 51 Substrate 52 Dielectric multilayer film 52R Red transmissive dichroic film 52G Green transmissive dichroic film 52B Blue transmissive dichroic film 52C Anti-reflection film 60 Rod integrator 70 DMD
80 Projection unit 100 Projection type image display device 111, 112, 113, 114 Lens 124 Mirror 131, 132 Lens 141 Diffusing plate 151, 152, 153 Lens 161, 162 Triangular prism 200 Main part 300 Second wavelength band light emitting unit 311 Mirror 312, 313, 314, 315, 316 Lens 320 Wavelength selective reflector 330 Second wavelength band fluorescent plate 331 Substrate 332 Reflective film 333 Second wavelength band phosphor film 334 Antireflection film 335 First wavelength band transmission dichroic film

Claims (8)

A solid-state light source that emits blue light in the first wavelength band with first polarized light,
A dichroic mirror that reflects one of the first polarized blue light, the second polarized blue light different from the first polarized light, and other colored light and transmits the other.
A phosphor wheel having a substrate provided with a segment provided with a first phosphor excited by the blue light reflected or transmitted by the dichroic mirror.
A first, which is provided between a wavelength selection reflector that reflects a part of the blue light and transmits the remaining blue light and other colored light, and the dichroic mirror and the substrate, and reciprocates to transmit the light. A retardation plate that converts polarized light into a second polarized light,
A fluorescent plate provided with a second phosphor that is on the long wavelength side of the first wavelength band and emits emitted light in a second wavelength band adjacent to the first wavelength band.
The blue light transmitted by the wavelength selection reflector is condensed to excite the second phosphor of the fluorescence plate, and the colored light emitted from the second phosphor is condensed and directed toward the wavelength selection reflector. The light emitting element and the light emitting element
A blue transmissive dichroic film in which the emitted light in the second wavelength band includes light in a third wavelength band adjacent to the first wavelength band and transmits only the blue light and the light in the third wavelength band. , With a light source device. The light source device according to claim 1, wherein the wavelength selection reflector is formed in one segment of the phosphor wheel. The light source device according to claim 1, wherein the wavelength selection reflector is located between the phosphor wheel and the fluorescent plate. The light source device according to claim 1 , wherein the blue-transmitting dichroic film is formed on the fluorescent plate . The light source device according to claim 1 , wherein the blue-transmitting dichroic film is formed on the wavelength-selective reflector . The light source device according to claim 1 , wherein the blue-transmitting dichroic film is formed in at least one segment on the phosphor wheel . A color wheel in which the blue light, the emitted light emitted by the first phosphor, and the emitted light of the second wavelength band are incident is provided, and the blue transmission dichroic film is placed on at least one segment on the color wheel. The light source device according to claim 1, which is formed . A projection type image display device using the light source device according to any one of claims 1 to 7.