JP5790815B2 - projector - Google Patents

Description

  The present invention relates to a projector, and more particularly to a projector using a solid light source.

  Conventionally, one solid light source device that emits white light, a color separation light guide optical system that separates light from one solid light source device into red light, green light, and blue light, and a color separation light guide optical system A projector is known that includes a light modulation device that modulates each color light according to image information and a projection optical system that projects the modulated light from the light modulation device as a projection image (see, for example, Patent Document 1). According to the projector described in Patent Document 1, the three color lights (red light, green light, and blue light) modulated by the light modulation device are obtained by color separation from one solid light source device that emits white light. Since the three color lights are used, the luminous efficiency (brightness per unit power) and temperature characteristics (change in light amount due to temperature change) are different for each solid light source device as in the case of a projector having three solid light source devices. As a result, the color balance of the projected image can be stabilized.

  Also, a solid light source device that emits red light, a solid light source device that emits green light, a solid light source device that emits blue light, and a light modulation device that modulates each color light from each solid light source device according to image information, A projector including a projection optical system that projects modulated light from a light modulation device as a projection image is known (see, for example, Patent Document 2). According to the projector described in Patent Document 2, a solid light source device that emits red light as three color lights (red light, green light, and blue light) modulated by the light modulation device, and a solid light source that emits green light. Since the three solid-state light source devices that emit the blue light and the three solid-state light source devices that emit blue light each use three colored light beams, the projected image can be made brighter than a projector including one solid-state light source device.

JP 2005-274957 A JP 2002-268140 A

  However, in the projector described in Patent Document 1, since white light including red light, green light, and blue light is generated from one solid light source device, the projector includes three solid light source devices. In contrast, a large thermal load is concentrated on one solid-state light source device. As a result, there is a problem that it is difficult to brighten the projected image.

  In the projector described in Patent Document 2, three solid light source devices for emitting red light, green light, and blue light (a solid light source device that emits red light and a solid light source device that emits green light) are disclosed. And the solid-state light source device that emits blue light) have a problem in that it is difficult to stabilize the color balance of the projected image.

  Therefore, the present invention has been made to solve the above-described problem, and can make a projected image brighter than a projector including one solid-state light source device, and can also be used from a projector including three solid-state light source devices. Another object of the present invention is to provide a projector capable of stabilizing the color balance of a projected image.

  [1] A projector according to the present invention includes a first solid-state light source that emits excitation light, a fluorescent layer that converts the excitation light into light including first color light and second color light different from the first color light, and emits the light. A first solid-state light source device, a second solid-state light source device including a second solid-state light source that emits third-color light different from both the first-color light and the second-color light, a first light modulation device, The first color light and the second color light are separated from the light emitted from the first light source device, and the first color light is separated from the first color light. A color separation light guide optical system that guides the light to the light modulator, guides the second color light to the second light modulator, and guides the third color light to the third light modulator; , First modulated light from the first light modulation device, second modulated light from the second light modulation device, and A cross dichroic prism that combines the third modulated light from the third light modulation device to form an image, and a projection optical system that projects the image from the cross dichroic prism as a projection image, The cross dichroic prism includes a first surface on which the first modulated light is incident, a second surface on which the second modulated light is incident, and a third surface on which the third modulated light is incident. The first surface is opposite to the third surface.

Therefore, according to the projector of the present invention, the two color lights (first color light and second light) emitted by the first solid-state light source device as the three color lights (red light, green light, and blue light) modulated by the light modulation device. Color light) and one color light (third color light) emitted by the second solid-state light source device are used, so that the thermal load applied to each solid-state light source device can be reduced as compared with a projector including one solid-state light source device. As a result, the projected image can be made brighter than a projector including one solid-state light source device.
According to the projector of the present invention, the same solid light source is used for two color lights (first color light and second color light) among the three color lights (red light, green light, and blue light) modulated by the light modulation device. Since it is generated using the (first solid light source), it is possible to stabilize the color balance of the projected image more than a projector including three solid light source devices.
As a result, the projector of the present invention can make the projected image brighter than a projector including one solid-state light source device, and can stabilize the color balance of the projected image as compared with a projector including three solid-state light source devices. It becomes a projector that can.

[2] In the projector according to the aspect of the invention, the color separation light guide optical system includes a first mirror, a second mirror, and a third mirror, and the light emitted from the first solid-state light source device is In addition, yellow light is included, the first color light is red light, the second color light is green light, the third color light is blue light, and the first mirror includes the red light and the yellow light. Is separated from the light emitted from the first solid-state light source device, emitted toward the second mirror, and the remaining light is emitted toward the third mirror, and the second mirror May be configured to remove the yellow light from the light emitted from the first solid state light source device by separating the light incident from the first mirror into the red light and the yellow light.

With this configuration, it is possible to emit light including red light and green light from the first solid light source device using the first solid light source that emits blue light. Further, yellow light can be removed from the light emitted from the first solid-state light source device.
In the projector according to the aspect of the invention, the color separation light guide optical system may include a first mirror, a second mirror, and a third mirror, and the light emitted from the first solid-state light source device may further include Including the excitation light, the first color light is red light, the second color light is green light, the third color light is blue light, and the first mirror includes the green light and the excitation light. Is separated from the light emitted from the first solid-state light source device, emitted toward the third mirror, and the remaining light is emitted toward the second mirror, and the third mirror May be configured to remove the excitation light from the light emitted from the first solid-state light source device by separating the light incident from the first mirror into the green light and the excitation light.
By comprising in this way, excitation light can be removed from the light inject | emitted from the 1st solid light source device.

  By the way, a solid light source used for a solid light source device that emits green light has a relatively higher luminous efficiency than a solid light source used for a solid light source device that emits red light and a solid light source device that emits blue light. There is a problem that it is low. On the other hand, according to the projector of the present invention, green light is generated using the first solid light source (emitting blue light) having higher luminous efficiency than the solid light source used in the solid light source device that emits green light. Therefore, it is possible to increase the light emission efficiency compared to using a solid light source device that emits green light.

  [3] In the projector according to the aspect of the invention, it is preferable that the first solid light source and the second solid light source have the same temperature characteristics.

  By configuring in this way, since the change in the light amount due to the change in temperature is uniform for all the color lights, the color balance of the projected image can be further stabilized.

  [4] In the projector of the present invention, the excitation light is ultraviolet light, the first color light is red light, the second color light is green light, and the third color light is blue light. preferable.

  With this configuration, it is possible to emit light including red light and green light from the first solid light source device using the first solid light source that emits ultraviolet light.

  In addition, since the first solid light source (emitting ultraviolet light) having higher luminous efficiency than the solid light source used in the solid light source device that emits green light is used to generate green light, the solid light source that emits green light. Luminous efficiency can be made higher than when an apparatus is used.

  Further, since there are many types of phosphors that efficiently convert ultraviolet light, the range of selection of phosphors in the phosphor layer is widened.

  [5] In the projector according to the aspect of the invention, it is preferable that the phosphor layer includes a layer containing a YAG phosphor, a silicate phosphor, or a TAG phosphor.

The above-described phosphor can efficiently convert the excitation light into light including red light and green light and emit the light, and the phosphor itself has high reliability. Therefore, the phosphor is configured as described above. As a result, the projected image can be brightened and a highly reliable projector can be obtained.
The YAG-based phosphor has a garnet structure as a basic structure such as (Y, Gd) ₃ (Al, Ga) ₅ O ₁₂ : Ce, and is basically a composite oxide of yttrium and aluminum. Refers to phosphor.
The silicate phosphor is a phosphor based on a silicate (silicate) into which various components are introduced, such as (Ca, Sr, Ba) SiO ₄ : Eu.
The TAG phosphor is a phosphor based on a complex oxide of terbium and aluminum having a garnet structure as a crystal structure such as Tb ₃ Al ₅ O ₁₂ : Ce.

  [6] The projector according to the aspect of the invention preferably has a function of removing yellow light from the light from the first solid-state light source device.

  With such a configuration, yellow light can be removed from the light from the first solid-state light source device, and as a result, deterioration of color reproducibility due to yellow light can be prevented.

  Note that the projector of the present invention may not have the function of removing yellow light from the light from the first solid-state light source device. In this case, yellow light that may be included in the light from the first solid-state light source device can be actively used, and a brighter projected image can be projected.

  [7] The projector of the invention preferably has a function of removing the excitation light from the light from the first solid-state light source device.

By the way, in the projector of the present invention, part of the excitation light emitted from the first solid-state light source device passes through the fluorescent layer as it is, and this causes deterioration of color reproducibility and deterioration of the light modulation device. May occur.
However, with the configuration as described above, it becomes possible to remove the excitation light from the light from the first solid-state light source device, and as a result, the color reproducibility deterioration and the light modulation device deterioration due to the excitation light are prevented. It becomes possible.

  [8] In the projector according to the aspect of the invention, the light emitted from the fluorescent layer is separated from the excitation light emitted as it is without being converted by the fluorescent layer, and the excitation light emitted as it is is converted into the fluorescent layer. It is preferable to further include an excitation light reflecting optical system that returns toward the back.

By the way, in the projector of the present invention, a part of the excitation light emitted from the first solid-state light source device passes through the fluorescent layer as it is. Degradation or degradation of the light modulation device may occur.
However, by adopting the configuration as described above, it is possible to improve the light utilization efficiency by reusing the excitation light by making the excitation light that has passed through the fluorescent layer as it is incident again into the fluorescent layer. It becomes possible to brighten the image. Further, by adopting the above configuration, it becomes possible to remove the excitation light from the light from the first solid-state light source device, and as a result, it prevents the color reproducibility deterioration and the light modulation device deterioration due to the excitation light. It becomes possible.

  [9] In the projector according to the aspect of the invention, the projector further includes a collimating optical system that collimates the light emitted from the first solid-state light source device, and the excitation light reflecting optical system is located at a subsequent stage of the collimating optical system. Is preferred.

  With this configuration, the excitation light that has passed through the fluorescent layer as it is and converted into parallel light by the collimating optical system is reflected by the excitation light reflecting optical system as parallel light, and then collected by the collimating optical system. Since the light efficiently enters the light emitting region of the fluorescent layer, it is possible to prevent the light emitting region from expanding due to the provision of the excitation light reflecting optical system.

  [10] In the projector according to the aspect of the invention, one of the polarization components included in the light emitted from the first solid-state light source device is allowed to pass through, and the other polarization component is reflected toward the fluorescent layer. It is preferable to further include a reflective polarizing plate.

By the way, when the light modulation device of the projector is a light modulation device using a liquid crystal light modulation device, only one of the polarization components included in the light is used for modulation, and the other polarization component is not used for modulation. It is common. Therefore, when a light source that emits light including both one polarization component and the other polarization component is used as the light source of the projector, it is necessary to remove the other polarization component by the incident-side polarizing plate. As a result, the light utilization efficiency decreases.
In contrast, by adopting the configuration as described above, the other polarization component is returned to the fluorescent layer and the other polarization component is reflected on the surface of the fluorescence layer, so that a part of the other polarization component is reflected on one side. It is possible to improve the light utilization efficiency by converting the light into the polarized light component and reusing it. As a result, the projected image can be brightened.

  [11] In the projector according to the aspect of the invention, the projector may further include a collimating optical system that collimates the light emitted from the first solid-state light source device, and the reflective polarizing plate may be located at a subsequent stage of the collimating optical system. preferable.

  By adopting such a configuration, the other polarization component converted into parallel light by the collimating optical system is reflected as parallel light by the reflective polarizing plate, and then collected by the collimating optical system to emit light from the fluorescent layer. Since the light efficiently enters the region, it is possible to prevent the light emitting region from being expanded due to the provision of the reflective polarizing plate.

  [12] In the projector according to the aspect of the invention, one of the polarization components included in the light emitted from the first solid-state light source device is allowed to pass as it is, and the other polarization component is reflected toward the fluorescent layer. It is preferable that the reflection-type polarizing plate is further provided, and the reflection-type polarizing plate is disposed at a subsequent stage of the excitation light reflection optical system.

By the way, if the reflective polarizing plate is disposed in front of the excitation light reflecting optical system, part of the excitation light reflected by the excitation light reflecting optical system is absorbed by the reflective polarizing plate, making it difficult to improve the light utilization efficiency. There is a case.
However, by configuring as described above, a part of the excitation light reflected by the excitation light reflecting optical system is not absorbed by the reflective polarizing plate, and thus it is possible to improve the light utilization efficiency. Become.

FIG. 2 is a plan view showing an optical system of the projector 1000 according to the first embodiment. FIG. 3 is a diagram illustrating a first solid light source device 20 and a second solid light source device 120 in the projector 1000 according to the first embodiment. 5 is a graph showing the relative light emission intensity of the first solid light source 24, the fluorescent layer 26, and the second solid light source 124 in the projector 1000 according to the first embodiment. FIG. 6 is a plan view showing an optical system of a projector 1002 according to a second embodiment. FIG. 6 is a plan view showing an optical system of a projector 1004 according to a third embodiment. FIG. 10 is a plan view showing an optical system of a projector 1006 according to a fourth embodiment. FIG. 10 is a plan view showing an optical system of a projector 1008 according to a fifth embodiment. The top view which shows the optical system of the projector 1010 which concerns on a modification.

  Hereinafter, a projector of the present invention will be described based on an embodiment shown in the drawings.

[Embodiment 1]
First, the configuration of the projector 1000 according to the first embodiment will be described.

FIG. 1 is a plan view showing an optical system of a projector 1000 according to the first embodiment.
FIG. 2 is a diagram illustrating the first solid light source device 20 and the second solid light source device 120 in the projector 1000 according to the first embodiment. 2A is a cross-sectional view of the first solid-state light source device 20, and FIG. 2B is a cross-sectional view of the second solid-state light source device 120.
FIG. 3 is a graph showing the relative light emission intensity of the first solid light source 24, the fluorescent layer 26, and the second solid light source 124 in the projector 1000 according to the first embodiment. 3A is a graph showing the relative emission intensity of the first solid-state light source 24, FIG. 3B is a graph showing the relative emission intensity of the fluorescent layer 26, and FIG. 3C is the second solid-state light source. It is a graph which shows the relative light emission intensity of 124. Relative light emission intensity is a characteristic of what wavelength of light is emitted at what intensity when a voltage is applied to a solid light source and excitation light is incident on a fluorescent layer. Say. The vertical axis of the graph represents relative light emission intensity, and the light emission intensity at the wavelength where the light emission intensity is strongest is 1. The horizontal axis of the graph represents the wavelength.

  As shown in FIG. 1, the projector 1000 according to the first embodiment includes a first illumination device 10, a second illumination device 110, a color separation light guide optical system 300, and three liquid crystal light modulation devices as light modulation devices. 400R, 400G, 400B, a cross dichroic prism 500, and a projection optical system 600 are provided.

  The first lighting device 10 includes a first solid-state light source device 20, a collimating optical system 30, and a rod integrator optical system 40.

  As shown in FIG. 2A, the first solid-state light source device 20 is a light-emitting diode having a base 22, a first solid-state light source 24, a fluorescent layer 26, and a sealing member 28, and includes red light, yellow light, and green light. Light including light is emitted (see FIG. 3B described later). The first solid-state light source device 20 has lead wires and the like in addition to the above-described components, but illustration and description thereof are omitted.

The base 22 is a base on which the first solid light source 24 is mounted.
The first solid-state light source 24 emits blue light (emission intensity peak: about 460 nm, see FIG. 3A) as excitation light. In FIG. 3A, what is indicated by a symbol B is a color light component emitted by the first solid light source 24 as excitation light (blue light). The first solid-state light source 24 is mainly composed of gallium nitride and has a pn bond type structure. The first solid-state light source may not have a pn junction type structure, and may have a double heterojunction type, a quantum well junction type, or the like.
A reflective layer (not shown) is formed between the first solid light source 24 and the base 22, and the blue light emitted from the first solid light source to the base 22 side is converted into a fluorescent layer by the reflective layer. Reflected toward the 26th side.

The fluorescent layer 26 is composed of a layer containing (Y, Gd) ₃ (Al, Ga) ₅ O ₁₂ : Ce, which is a YAG phosphor, and is disposed on the illuminated region side of the first solid-state light source 24. The fluorescent layer 26 is most efficiently excited by blue light having a wavelength of about 460 nm. As shown in FIG. 3B, the blue light emitted from the first solid light source 24 is converted into red light (emission intensity peak: about 610 nm), yellow light (emission intensity peak: about 580 nm), and green light (emission intensity peak: about 550 nm). In FIG. 3B, reference numeral R denotes a color light component that can be used as red light out of the light emitted from the fluorescent layer 26. Reference numeral G denotes a color light component that can be used as green light in the light emitted from the fluorescent layer 26. Reference numeral Y denotes a color light component emitted from the fluorescent layer as yellow light.
The sealing member 28 is made of a transparent epoxy resin and protects the first solid light source 24 and the fluorescent layer 26.

  As shown in FIG. 1, the collimating optical system 30 includes a convex meniscus lens 32 that suppresses the spread of light from the first solid-state light source device 20, and a convex lens 34 that collimates the light from the convex meniscus lens 32. As, it has a function which makes the light from the 1st solid light source device 20 parallel.

The rod integrator optical system 40 includes a convex lens 42, a rod lens 44, and a convex lens 46.
The convex lens 42 condenses the parallel light from the collimating optical system 30 and guides it to the incident surface of the rod lens 44.
The rod lens 44 is a solid columnar lens, and makes light incident from the incident surface uniform by multiple reflection on the inner surface, and emits light having a uniform in-plane light intensity distribution from the emission surface. As the rod lens, a hollow columnar lens can be used instead of the solid columnar lens.
The convex lens 46 substantially collimates the light emitted from the exit surface of the rod lens 44 and guides the light to the image forming area in the liquid crystal light modulation devices 400R and 400G.

  The second illumination device 110 includes a second solid-state light source device 120, a collimating optical system 130, and a rod integrator optical system 140.

2B, the second solid-state light source device 120 is a light emitting diode having a base 122, a second solid-state light source 124, and a sealing member 128, and emits blue light (see FIG. 3 (described later)). see c)). The second solid-state light source device 120 has lead wires and the like in addition to the above-described components, but illustration and description thereof are omitted.
As shown in FIG. 3C, the second solid light source 124 emits blue light (emission intensity peak: about 460 nm) as colored light. In FIG. 3C, reference numeral B denotes a color light component emitted by the second solid light source 124 as color light (blue light).
Since the base 122 has the same configuration as the base 22, the second solid light source 124 has the same configuration as the first solid light source 24, and the sealing member 128 has the same configuration as the sealing member 28, detailed description will be omitted.

  The first solid light source 24 and the second solid light source 124 are made of the same material and the same manufacturing method, and have the same structure. For this reason, the first solid-state light source 24 and the second solid-state light source 124 have the same temperature characteristics, and the change in the amount of light due to the change in temperature is equal to each other.

  As shown in FIG. 1, the collimating optical system 130 includes a convex meniscus lens 132 that suppresses the spread of light from the second solid-state light source device 120, and a convex lens 134 that collimates the light from the convex meniscus lens 132. As, it has a function which makes the light from the 2nd solid light source device 120 parallel.

The rod integrator optical system 140 includes a convex lens 142, a rod lens 144, and a convex lens 146.
The convex lens 142 collects the parallel light from the collimating optical system 130 and guides it to the incident surface of the rod lens 144.
The rod lens 144 is a solid columnar lens, which makes light incident from the incident surface uniform by multiple reflection on the inner surface, and emits light from the exit surface with uniform in-plane light intensity distribution. As the rod lens, a hollow columnar lens can be used instead of the solid columnar lens.
The convex lens 146 substantially parallelizes the light emitted from the exit surface of the rod lens 144 and guides the light to the image forming area in the liquid crystal light modulation device 400B.

  The color separation light guide optical system 300 includes a dichroic mirror 310 disposed in the front stage of the optical path, dichroic mirrors 320 and 330 disposed in the rear stage of the optical path, and a reflection mirror 340 for blue light. The color separation light guide optical system 300 separates the light from the first illumination device 10 into red light and green light, and guides the red light and green light to the liquid crystal light modulation devices 400R and 400G to be illuminated. And a function of guiding blue light from the second illumination device 110 to the liquid crystal light modulation device 400B to be illuminated.

The dichroic mirrors 310, 320, and 330 are mirrors on which a wavelength selective transmission film that reflects light in a predetermined wavelength region and allows light in other wavelength regions to pass is formed on a substrate.
The dichroic mirror 310 is a dichroic mirror that reflects a green light component and a blue light component and passes a red light component and a yellow light component.
The dichroic mirror 320 is a dichroic mirror that reflects a red light component and transmits a yellow light component. The yellow light component that has passed through the dichroic mirror 320 is removed out of the system. That is, the projector 1000 has a function of removing yellow light by the dichroic mirror 320. In FIG. 1, a dotted arrow (see symbol Y) extending from the dichroic mirror 320 indicates yellow light that has passed through the dichroic mirror 320.
The dichroic mirror 330 is a dichroic mirror that reflects the green light component and transmits the blue light component. The blue light component that has passed through the dichroic mirror 330 is removed out of the system. That is, the projector 1000 has a function of removing excitation light (blue light) by the dichroic mirror 330. In FIG. 1, a dotted line arrow (see symbol B) extending from the dichroic mirror 330 indicates blue light that has passed through the dichroic mirror 330.

The red light that has passed through the dichroic mirror 310 is reflected by the dichroic mirror 320 and enters the image forming area of the liquid crystal light modulation device 400R for red light.
The green light reflected by the dichroic mirror 310 is further reflected by the dichroic mirror 330 and enters the image forming area of the liquid crystal light modulation device 400G for green light.
The blue light from the second illumination device 110 is reflected by the reflection mirror 340 and enters the image forming region of the blue light liquid crystal light modulation device 400B.

The liquid crystal light modulators 400R, 400G, and 400B modulate incident color light in accordance with image information to form a color image, and are illumination targets of the first illumination device 10 and the second illumination device 110. Although not shown in the figure, the light is incident between the dichroic mirror 320 and the liquid crystal light modulation device 400R, between the dichroic mirror 330 and the liquid crystal light modulation device 400G, and between the reflection mirror 340 and the liquid crystal light modulation device 400B. A side polarizing plate is disposed, and an exit side polarizing plate is disposed between the liquid crystal light modulation devices 400R, 400G, and 400B and the cross dichroic prism 500, respectively. The incident-side polarizing plates, the liquid crystal light modulation devices 400R, 400G, and 400B and the exit-side polarizing plate modulate the light of each incident color light.
The liquid crystal light modulators 400R, 400G, and 400B are transmissive liquid crystal light modulators in which a liquid crystal that is an electro-optical material is hermetically sealed in a pair of transparent glass substrates. In accordance with the received image signal, the polarization direction of one type of linearly polarized light emitted from the incident side polarizing plate is modulated.

  The cross dichroic prism 500 is an optical element that forms a color image by synthesizing an optical image modulated for each color light emitted from the emission side polarizing plate. The cross dichroic prism 500 has a substantially square shape in plan view in which four right-angle prisms are bonded together, and a dielectric multilayer film is formed on a substantially X-shaped interface in which the right-angle prisms are bonded together. The dielectric multilayer film formed at one of the substantially X-shaped interfaces reflects red light, and the dielectric multilayer film formed at the other interface reflects blue light. By these dielectric multilayer films, the red light and the blue light are bent and aligned with the traveling direction of the green light, so that the three color lights are synthesized.

  The color image emitted from the cross dichroic prism 500 is enlarged and projected by the projection optical system 600 to form an image on the screen SCR.

  Next, effects of the projector 1000 according to the first embodiment will be described.

According to the projector 1000 according to the first embodiment, two color lights emitted by the first solid-state light source device 20 as three color lights (red light, green light, and blue light) modulated by the liquid crystal light modulation devices 400R, 400G, and 400B. (Red light and green light) and one color light (blue light) emitted by the second solid state light source device 120 are used, so that a thermal load applied to each solid state light source device rather than a projector including one solid state light source device As a result, it is possible to make the projected image brighter than a projector including one solid-state light source device.
Further, according to the projector 1000 according to the first embodiment, two color lights (red light and green light) among the three color lights (red light, green light, and blue light) modulated by the liquid crystal light modulation devices 400R, 400G, and 400B. Is generated using the same solid-state light source (first solid-state light source 24), the color balance of the projected image can be stabilized more than a projector including three solid-state light source devices.
As a result, the projector 1000 according to the first embodiment can make the projected image brighter than a projector including one solid-state light source device, and has a color balance of the projected image higher than that of a projector including three solid-state light source devices. The projector can be stabilized.

  Further, according to the projector 1000 according to the first embodiment, the excitation light is blue light, the first color light is red light, the second color light is green light, and the third color is blue light. Light including red light and green light can be emitted from the first solid-state light source device 20 using the first solid-state light source 24 that emits blue light.

  Further, according to the projector 1000 according to the first embodiment, green light is generated using the first solid-state light source 24 (emitting blue light) having higher luminous efficiency than the solid-state light source used in the solid-state light source device that emits green light. Therefore, it is possible to increase the light emission efficiency compared to using a solid light source device that emits green light.

  Further, according to the projector 1000 according to the first embodiment, since the first solid light source 24 and the second solid light source 124 have the same temperature characteristics, the change in the amount of light due to the change in temperature is uniform for all the color lights. Thus, the color balance of the projected image can be further stabilized.

Further, according to the projector 1000 according to the first embodiment, since the fluorescent layer 26 is made of a layer containing (Y, Gd) ₃ (Al, Ga) ₅ O ₁₂ : Ce, which is a YAG phosphor, a projected image is displayed. It is possible to make the projector brighter and more reliable.

  In addition, according to the projector 1000 according to the first embodiment, the dichroic mirror 320 has a function of removing yellow light from the light from the first solid light source device 20, so yellow light is emitted from the light from the first solid light source device 20. As a result, it is possible to prevent deterioration of color reproducibility due to yellow light.

  Further, the projector 1000 according to the first embodiment has a function of removing excitation light (blue light) from the light from the first solid-state light source device 20 by the dichroic mirror 330, and thus the light from the first solid-state light source device 20. It is possible to remove excitation light (blue light) from the light source, and as a result, it is possible to prevent deterioration of color reproducibility and deterioration of the light modulation device due to excitation light (blue light).

[Embodiment 2]
FIG. 4 is a plan view showing an optical system of the projector 1002 according to the second embodiment.

The projector 1002 according to the second embodiment basically has the same configuration as the projector 1000 according to the first embodiment, but the configuration of the first illumination device and the configuration of the color separation light guide optical system according to the first embodiment. This is different from 1000.
That is, in the projector 1002 according to the second embodiment, as shown in FIG. 4, the first illumination device 12 is positioned behind the collimating optical system 30 and emits light (red light, green light) emitted from the fluorescent layer 26. And yellow light) and excitation light (blue light) emitted as it is without being converted in the fluorescent layer 26, and excitation light reflection that returns the excitation light (blue light) emitted as it is to the fluorescent layer 26 An excitation light reflecting mirror 50 as an optical system is further provided. The excitation light reflecting mirror 50 is a dichroic mirror in which a wavelength selective transmission film that reflects blue light and transmits red light, green light, and yellow light is formed on a substrate. In FIG. 4, a dotted line arrow (see reference symbol B) extending from the excitation light reflecting mirror 50 indicates blue light reflected by the excitation light reflecting mirror 50.
As a result, excitation light (blue light) is not incident on the color separation / light guiding optical system 302, so that the dichroic mirror 330 having a function of removing excitation light (blue light) is not necessary. For this reason, the color separation light guide optical system 302 includes a reflection mirror 350 instead of the dichroic mirror 330.

  As described above, the projector 1002 according to the second embodiment differs from the projector 1000 according to the first embodiment in the configuration of the first illumination device and the color separation light guide optical system, but the liquid crystal light modulation devices 400R and 400G. , 400B modulated as three color lights (red light, green light and blue light), two color lights (red light and green light) emitted by the first solid light source device 20 and one emitted by the second solid light source device. Of the three color lights (red light, green light, and blue light) that use color light (blue light) and that are modulated by the liquid crystal light modulators 400R, 400G, and 400B, Since the same solid-state light source (first solid-state light source 24) is used for generation, similarly to the projector 1000 according to the first embodiment, a project including one solid-state light source device is used. It can brighten the projection image than compactors, and the three solid-state light source capable projectors to stabilize the color balance of the projected image than a projector provided with a device.

  In addition, according to the projector 1002 according to the second embodiment, since the excitation light reflecting mirror 50 is further provided, excitation light (blue light) that has passed through the fluorescent layer 26 as it is is incident on the fluorescent layer 26 again, thereby exciting light (blue). Light) can be reused to improve the light utilization efficiency, and as a result, the projected image can be brightened. Moreover, it becomes possible to remove excitation light (blue light) from the light from the first solid-state light source device 20, and as a result, it is possible to prevent deterioration of color reproducibility and deterioration of the light modulation device due to excitation light (blue light). Is possible.

  Further, according to the projector 1002 according to the second embodiment, since the excitation light reflecting mirror 50 is located at the rear stage of the collimating optical system 30, the excitation light (which passes through the fluorescent layer 26 as it is and converted into parallel light by the collimating optical system 30 ( (Blue light) is reflected by the excitation light reflecting mirror 50 as parallel light, then condensed by the collimating optical system 30, and efficiently enters the light emitting region of the fluorescent layer 26. Therefore, the excitation light reflecting mirror 50 It is possible to prevent the light emitting region from expanding due to the further provision of the above.

  The projector 1002 according to the second embodiment has the same configuration as that of the projector 1000 according to the first embodiment except for the configuration of the first illumination device and the configuration of the color separation light guide optical system. Among the effects that the projector 1000 according to the invention has, the corresponding effects are provided as they are.

[Embodiment 3]
FIG. 5 is a plan view showing an optical system of the projector 1004 according to the third embodiment.

The projector 1004 according to the third embodiment basically has the same configuration as the projector 1002 according to the second embodiment, but the configuration of the first illumination device is different from that of the projector 1002 according to the second embodiment.
That is, in the projector 1004 according to the third embodiment, the first illumination device 14 is located in the rear stage of the collimating optical system 30 and is included in the light emitted from the first solid-state light source device 20 as shown in FIG. A reflective polarizing plate 52 is further provided that allows one of the polarization components (for example, the s-polarization component) to pass as it is and reflects the other polarization component (for example, the p-polarization component) toward the fluorescent layer 26. The reflective polarizing plate 52 is a wire grid polarizing plate having ultrafine metal wires arranged in a lattice pattern at a specific pitch. As the reflective polarizing plate, a polarizing beam splitter (PBS) in which a dielectric multilayer film is formed on a substrate can be used instead of the wire grid polarizing plate. In FIG. 5, a solid line arrow (see reference signs R (p), G (p), and Y (p)) extending from the reflective polarizing plate 52 represents the other polarization component reflected by the reflective polarizing plate 52. is there.

  As described above, the projector 1004 according to the third embodiment is different from the projector 1002 according to the second embodiment in the configuration of the first illumination device, but the three color lights modulated by the liquid crystal light modulation devices 400R, 400G, and 400B ( Two color lights (red light and green light) emitted from the first solid-state light source device 20 and one color light (blue light) emitted from the second solid-state light source device are used as red light, green light, and blue light. Of the three color lights (red light, green light and blue light) modulated by the liquid crystal light modulation devices 400R, 400G and 400B, the same solid light source (first solid light source) is used for two color lights (red light and green light). 24), the projected image is brighter than the projector having one solid-state light source device, as in the case of the projector 1002 according to the second embodiment. Can Kusuru and the three solid-state light source capable projectors to stabilize the color balance of the projected image than a projector provided with a device.

  Further, according to the projector 1004 according to the third embodiment, since the reflective polarizing plate 52 is further provided, the other polarized component is returned to the fluorescent layer 26 and the other polarized component is reflected on the surface of the fluorescent layer 26. In addition, it is possible to improve the light utilization efficiency by converting a part of the other polarization component into one polarization component and reusing it. As a result, the projected image can be brightened.

  Further, according to the projector 1004 according to the third embodiment, since the reflective polarizing plate 52 is located at the subsequent stage of the collimating optical system 30, the other polarization component converted into parallel light by the collimating optical system 30 is the reflective polarizing plate. Since the light is reflected by the collimating optical system 30 after being reflected by the collimated optical system 52 and is efficiently incident on the light emitting region of the fluorescent layer 26, light is emitted due to the provision of the reflective polarizing plate 52. It is possible to suppress the area from expanding.

  Further, according to the projector 1004 according to the third embodiment, since the reflective polarizing plate 52 is disposed at the subsequent stage of the excitation light reflecting mirror 50, a part of the excitation light reflected by the excitation light reflecting mirror 50 is a reflection type. Since the light is not absorbed by the polarizing plate 52, the light utilization efficiency can be improved.

  Note that the projector 1004 according to the third embodiment has the same configuration as the projector 1002 according to the second embodiment except for the configuration of the first lighting device, and thus, among the effects of the projector 1002 according to the second embodiment. Has the relevant effect as it is.

[Embodiment 4]
FIG. 6 is a plan view showing an optical system of the projector 1006 according to the fourth embodiment.

The projector 1006 according to the fourth embodiment basically has the same configuration as that of the projector 1002 according to the second embodiment, but the configuration of the light modulation device and the configuration of the color separation light guide optical system are the projector 1002 according to the second embodiment. It is different from the case of.
That is, in the projector 1006 according to the fourth embodiment, as shown in FIG. 6, the light modulation device includes reflection type liquid crystal light modulation devices 402R, 402G, and 402B. In addition, the color separation light guide optical system reflects the green light component and allows the other color light component to pass through, and the one polarization component (for example, the s polarization component) as it is, and the other polarization component (p The color separation light guide optical system 304 includes reflective polarizing plates 322, 332, and 342 that reflect the polarization component). The reflective polarizing plate 322 also has a function as a dichroic mirror that reflects the yellow light component and transmits the red light component. The reflective polarizing plate 322 has, for example, ultrafine metal wires arranged in a lattice pattern at a specific pitch as a wire grid polarizing plate on one surface of the substrate, and a dichroic mirror on the other surface of the substrate. As an optical element having a wavelength selective transmission film. That is, the projector 1006 has a function of removing yellow light by the reflective polarizing plate 322.

  The liquid crystal light modulators 402R, 402G, and 402B perform light modulation of incident color light together with the reflective polarizing plates 322, 332, and 342 in the color separation light guide optical system 304. The color separation light guide optical system 304 separates the light from the first illumination device 10 into red light and green light, and guides the respective color light of red light and green light to the liquid crystal light modulation devices 402R and 402G to be illuminated. Light and the function of guiding the light reflected by the liquid crystal light modulators 402R and 402G to the cross dichroic prism 500 as modulated light and the blue light from the second illumination device 110 to the liquid crystal light modulator 402B to be illuminated. The light has a function of guiding the light reflected by the liquid crystal light modulation device to the cross dichroic prism 500 as modulated light.

  As described above, the projector 1006 according to the fourth embodiment differs from the projector 1002 according to the second embodiment in the configuration of the light modulation device and the color separation light guide optical system, but the liquid crystal light modulation devices 402R and 402G. , 402B as three color lights (red light, green light and blue light), two color lights (red light and green light) emitted by the first solid light source device 20 and one emitted by the second solid light source device. Of the three color lights (red light, green light, and blue light) that use color light (blue light) and that are modulated by the liquid crystal light modulators 402R, 402G, and 402B, Since the same solid-state light source (first solid-state light source 24) is used for generation, similarly to the projector 1002 according to the second embodiment, the projector having one solid-state light source device is used. It can brighten the projection image than Ekuta and the three solid-state light source capable projectors to stabilize the color balance of the projected image than a projector provided with a device.

  The projector 1006 according to the fourth embodiment has the same configuration as that of the projector 1002 according to the second embodiment except for the configuration of the light modulation device and the configuration of the color separation light guide optical system. This has the same effect as the projector 1002 has.

[Embodiment 5]
FIG. 7 is a plan view showing an optical system of the projector 1008 according to the fifth embodiment.

The projector 1008 according to the fifth embodiment basically has the same configuration as the projector 1000 according to the first embodiment, but the configuration of the first lighting device and the configuration of the second lighting device are the same as those of the projector 1000 according to the first embodiment. Not the case.
That is, in the projector 1008 according to the fifth embodiment, as illustrated in FIG. 7, the first illumination device 16 includes a lens integrator optical system 60 instead of the rod integrator optical system 40, and the second illumination device 112 includes a rod. A lens integrator optical system 160 is provided instead of the integrator optical system 140. The lens integrator optical system 60 includes a first lens array 62, a second lens array 64, and a superimposing lens 66. The lens integrator optical system 160 includes a first lens array 162, a second lens array 164, and a superimposing lens 166.

  As described above, the projector 1008 according to the fifth embodiment is different from the projector 1000 according to the first embodiment in the configuration of the first illumination device and the configuration of the second illumination device, but the liquid crystal light modulation devices 400R, 400G, and 400B. As the three color lights (red light, green light, and blue light) modulated in Step 1, the two color lights (red light and green light) emitted by the first solid light source device 20 and the one color light (second light source device emitted by the second solid light source device). Blue light) and two color lights (red light and green light) among the three color lights (red light, green light, and blue light) modulated by the liquid crystal light modulators 400R, 400G, and 400B are the same. Since it is generated using the solid light source (first solid light source 24), the projector including one solid light source device is provided, as in the case of the projector 1000 according to the first embodiment. It can brighten the projection image than over, and the three solid-state light source capable projectors to stabilize the color balance of the projected image than a projector provided with a device.

  The projector 1008 according to the fifth embodiment has the same configuration as that of the projector 1000 according to the first embodiment except for the configuration of the first lighting device and the configuration of the second lighting device. It has the same effect as the effect that the projector 1000 has.

  As mentioned above, although this invention was demonstrated based on said embodiment, this invention is not limited to said embodiment. The present invention can be carried out in various modes without departing from the spirit thereof, and for example, the following modifications are possible.

(1) In each of the above embodiments, the fluorescent layer 26 is composed of a layer containing (Y, Gd) ₃ (Al, Ga) ₅ O ₁₂ : Ce, but the present invention is limited to this. is not. For example, the fluorescent layer may be a layer containing a YAG phosphor other than (Y, Gd) ₃ (Al, Ga) ₅ O ₁₂ : Ce, or a layer containing a silicate phosphor. Or a layer containing a TAG phosphor. Further, the fluorescent layer may be composed of a layer containing a mixture of a phosphor that converts excitation light into red light and a phosphor that converts excitation light into green.

  (2) In each of the above embodiments, the liquid crystal light modulation device is used as the light modulation device of the projector, but the present invention is not limited to this. In general, the light modulation device only needs to modulate incident light according to image information, and a micromirror light modulation device or the like may be used. For example, a DMD (digital micromirror device) (trademark of TI) can be used as the micromirror light modulator.

  (3) In each of the above embodiments, the first solid light source device 20 and the second solid light source device 120 are made of light emitting diodes, but the present invention is not limited to this. The first solid light source device and the second solid light source device may be made of, for example, a semiconductor laser, or may be made of an organic light emitting diode.

  (4) In the above embodiments, the excitation light is blue light, but the present invention is not limited to this. The excitation light may be ultraviolet light. Also with this configuration, it becomes possible to emit light including red light and green light from the first lighting device, and the luminous efficiency is made higher than when using a solid light source device that emits green light. In addition, the range of selection of phosphors in the phosphor layer is widened.

  (5) In each of the above embodiments, when the excitation light is ultraviolet light, the first color light may be green light, the second color light may be blue light, the third color light may be red light, or the first color light May be red light, the second color light may be blue light, and the third color light may be green light.

  (6) In the first to third embodiments, the projector has a function of removing yellow light from the first solid-state light source device 20, but the present invention is not limited to this. For example, the projector may not have a function of removing yellow light. In this case, yellow light included in the light from the first lighting device can be actively used, and a brighter projection image can be projected. In addition, when yellow light is not removed, the yellow light is modulated by using a light modulation device different from red light and green light, so that a projected image with better color reproducibility can be obtained in addition to the above effects. The effect that it becomes possible to project can be obtained.

  (7) In Embodiment 3 described above, the first illumination device 14 includes both the excitation light reflecting mirror 50 and the reflective polarizing plate 52, but the present invention is not limited to this. For example, the excitation light reflecting mirror may not be provided.

  (8) In each of the above embodiments, the projector may further include a polarization conversion device. The polarization conversion device is a polarization conversion element that converts light including both one polarization component and the other polarization component into substantially one type of linearly polarized light having a uniform polarization direction.

  (9) In each of the above embodiments, the collimating optical systems 30 and 130 include two lenses, the convex meniscus lenses 32 and 132 and the convex lenses 34 and 134, but the present invention is not limited to this. For example, the collimating optical system may include only one lens, or may include three or more lenses.

  (10) The shape of each lens used in the optical path of the projector in each of the above embodiments is not limited to that described in each of the above embodiments. If necessary, lenses having various shapes can be used.

  (11) In each of the above embodiments, a projector using three liquid crystal light modulation devices has been described as an example, but the present invention is not limited to this. The present invention can also be applied to a projector using one, two, four or more liquid crystal light modulation devices.

  (12) The present invention can be applied to a rear projection type projector that projects from a side opposite to the side that observes the projected image, even when applied to a front projection type projector that projects from the side that observes the projected image. Is also possible.

  (13) In Embodiments 2 and 3, the excitation light reflecting mirror 50 is used as the excitation light reflecting optical system, but the present invention is not limited to this. FIG. 8 is a plan view showing an optical system of a projector 1010 according to a modification. As shown in FIG. 8, as the excitation light reflecting optical system, light (red light, green light, and yellow light) emitted from the fluorescent layer 26 and excitation light (blue light) emitted as it is without being converted by the fluorescent layer. An excitation light reflecting optical system may be used that includes a dichroic mirror 54 that separates the light and the reflection mirror 56 that reflects the excitation light (blue light) from the dichroic mirror 54 toward the fluorescent layer 26. With this configuration as well, in the same way as in the second and third embodiments, it is possible to make the projected image brighter, and prevent deterioration of color reproducibility and light modulator due to excitation light. Is possible.

  DESCRIPTION OF SYMBOLS 10, 12, 14, 16, 18 ... 1st illuminating device, 20 ... 1st solid light source device, 22, 122 ... Base, 24 ... 1st solid light source, 26 ... Fluorescent layer, 28, 128 ... Sealing member, 30, 130 ... collimating optical system, 32, 132 ... convex meniscus lens, 34, 42, 46, 134, 142, 146 ... convex lens, 40, 140 ... rod integrator optical system, 44, 144 ... rod lens, 50 ... excitation light Reflective mirror, 52, 322, 332, 342 ... reflective polarizing plate, 54, 310, 320, 330 ... dichroic mirror, 56, 340, 350 ... reflective mirror, 60, 160 ... lens integrator optical system, 62, 162 ... first 1 lens array, 64, 164 ... second lens array, 66, 166 ... superimposing lens, 110, 112 ... second illumination device, 120 ... second Body light source device, 124 ... second solid light source, 300, 302, 304 ... color separation light guide optical system, 400R, 400G, 400B, 402R, 402G, 402B ... liquid crystal light modulation device, 500 ... cross dichroic prism, 600 ... projection Optical system, 1000, 1002, 1004, 1006, 1008, 1010 ... projector, SCR ... screen.

Claims (5)

A first solid-state light source that emits excitation light; and a fluorescent layer that converts the excitation light emitted from the first solid-state light source into light containing first color light and second color light different from the first color light and emits the light. A first solid state light source device comprising:
A second solid-state light source device comprising a second solid-state light source that emits a third color light different from both the first color light and the second color light;
A first light modulation device;
A second light modulation device;
A third light modulation device;
The first color light and the second color light are separated from the light emitted from the first solid state light source device, the first color light is guided to the first light modulation device, and the second color light is converted to the first color light. A color separation light guiding optical system that guides the light to the second light modulation device and guides the third color light to the third light modulation device;
The first modulated light from the first light modulation device, the second modulated light from the second light modulation device, and the third modulated light from the third light modulation device are combined. Cross dichroic prism to form an image,
The cross dichroic and a projection optical system for projecting a projection image of the image from the click prism,
The cross dichroic prism includes a first surface on which the first modulated light is incident, a second surface on which the second modulated light is incident, and a third surface on which the third modulated light is incident. Have
The first surface to the projectors characterized that you have to face the third surface. The projector according to claim 1, wherein the optical path of the third color light is arranged so as not to intersect the optical path of the second color light. The projector according to claim 1 or 2 ,
The color separation light guide optical system includes a first mirror, a second mirror, and a third mirror,
The light emitted from the first solid state light source device further includes yellow light,
The first color light is red light;
The second color light is green light;
The third color light is blue light;
The first mirror separates the light including the red light and the yellow light from the light emitted from the first solid-state light source device and emits the light toward the second mirror, and the remaining light is emitted from the first mirror. Ejected towards 3 mirror,
The second mirror removes the yellow light from the light emitted from the first solid-state light source device by separating the light incident from the first mirror into the red light and the yellow light. Projector. The projector according to claim 1 or 2 ,
The color separation light guide optical system includes a first mirror, a second mirror, and a third mirror,
The light emitted from the first solid state light source device further includes the excitation light,
The first color light is red light;
The second color light is green light;
The third color light is blue light;
The first mirror separates the light including the green light and the excitation light from the light emitted from the first solid state light source device and emits the light toward the third mirror, and the remaining light is emitted from the first mirror. Ejected towards the mirror 2
The third mirror removes the excitation light from the light emitted from the first solid-state light source device by separating the light incident from the first mirror into the green light and the excitation light. Projector. In the projector as described in any one of Claims 1 thru | or 4 ,
The projector according to claim 1, wherein the first solid-state light source and the second solid-state light source have the same temperature characteristics.

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