WO2016148210A1

WO2016148210A1 - Light source device and projection device

Info

Publication number: WO2016148210A1
Application number: PCT/JP2016/058401
Authority: WO
Inventors: 小林大介
Original assignee: コニカミノルタ株式会社
Priority date: 2015-03-18
Filing date: 2016-03-16
Publication date: 2016-09-22

Abstract

Provided is a light source device that uniformly illuminates the entire surface of the effective region of a phosphor and that can reduce the size of the optical system of a light source. Also provided is a projection device incorporating the light source device. A light source device 21 is provided with the following: a laser-beam forming unit 31 that projects excitation light EL; a phosphor 41 that radiates fluorescence FL as a result of the excitation light EL being projected thereto; a polarizing dichroic mirror 32 that is disposed on the light path between the laser beam forming unit 31 and the phosphor 41, and that splits the fluorescence FL from the light path of the excitation light EL; and a fly's-eye optical system 36 that equalizes the intensity distribution of the excitation light EL and the intensity distribution of the fluorescence FL. The fly's-eye optical system 36 equalizes the intensity distribution of both the excitation light EL and the fluorescence FL as a result of at least a portion of the fly's-eye optical system 36 being disposed on the light path between the polarizing dichroic mirror 32 and the phosphor 41, and as a result thereof, the fly's-eye optical system 36 can reduce the size and cost of the light source device 21 and uniformly illuminate the effective region of the phosphor 41 using the excitation light EL.

Description

Light source device and projection device

The present invention relates to a light source device for illuminating an image display element incorporated in a projection device, and a projection device incorporating such a light source device.

In recent years, phosphors have come to be used as light sources for projectors (projectors). In these projectors, light emitted from a laser diode or LED is irradiated onto a phosphor, and the fluorescence emitted by wavelength conversion by the phosphor is used (see Patent Documents 1 to 3). The fluorescence emitted from the phosphor is applied to an image display element such as a liquid crystal or DMD (digital micromirror device), and an image formed by the image display element is enlarged and projected onto a screen by a projection optical system. Here, if the intensity of the excitation light applied to the phosphor is increased by increasing the output of the excitation light source in order to brighten the projected image on the screen, there is a problem that the light emission efficiency decreases due to the saturation phenomenon of the phosphor. Further, when the excitation light intensity is high, there is a problem that the phosphor is deteriorated and the life is shortened. For these two reasons, it is desirable that the excitation light intensity is not excessively high.

An area on the surface of the phosphor where the fluorescence can reach the image display element when the phosphor emits light is defined as an effective area. This effective area usually has a rectangular shape having substantially the same aspect ratio as that of the image display element. In order not to excessively increase the excitation light intensity, it is desirable to irradiate the excitation light in a uniform state over the entire effective area of the phosphor. To that end, it is conceivable to incorporate the fly-eye lens of Patent Document 1 in the excitation light source system and irradiate the phosphor with excitation light. For this reason, if a fly-eye lens is added to the excitation light source system, the light source This increases the size of the optical system and increases the cost.

JP2012-118110A JP 2014-2839 A International Publication No. 2011/092842

The present invention has been made in view of the above-described background art, and a light source device for a projection device that can suppress an increase in the size of an optical system of a light source while uniformly illuminating the entire effective area of a phosphor, and the same An object of the present invention is to provide a projection apparatus incorporating the above.

To achieve the above object, a light source device for a projection apparatus according to the present invention includes an excitation light source that emits excitation light, a phosphor that emits fluorescence when irradiated with excitation light, an excitation light source, and a phosphor. A beam splitter for branching the fluorescence from the optical path of the excitation light, and a fly-eye optical system for equalizing the intensity distribution of the excitation light and the intensity distribution of the fluorescence, the beam splitter and the phosphor At least a part of the fly-eye optical system is disposed in the optical path between the two.

In order to achieve the above object, a projection apparatus according to the present invention includes a light source device for the projection apparatus described above, an image display element illuminated by the light source apparatus for the projection apparatus, and an image display element. A projection optical system for projecting an image.

It is a figure explaining the projection apparatus containing the light source device for projection apparatuses which concerns on 1st Embodiment. It is a figure explaining an example of the fluorescent substance wheel provided in the light source device shown in FIG. 3A shows a front view of the first fly-eye lens viewed from the optical axis direction, FIG. 3B shows a front view of the second fly-eye lens, and FIG. 3C shows a front view of the third fly-eye lens. . FIG. 4A is a diagram illustrating a light source device for a projection device according to the second embodiment, and FIG. 4B is a diagram illustrating a phosphor wheel or a phosphor incorporated in the light source device of FIG. 4A. It is a figure explaining the light source device etc. for projectors of a 3rd embodiment.

[First Embodiment]
Hereinafter, a projection apparatus incorporating a light source device for a projection apparatus according to a first embodiment of the present invention will be described with reference to the drawings.

As shown in FIG. 1, the projection device 2 according to the first embodiment enables projection of images corresponding to various video signals, and includes a light source device 21, a polarization beam splitter 22, and a reflective liquid crystal element 23. , A projection optical system 24, and an image drive circuit 25.

The light source device 21 includes a laser beam forming unit 31 that emits a substantially parallel laser beam L1, a polarization dichroic mirror 32 that branches the optical path of the fluorescence FL from the optical path of the laser beam L1, and a position that changes the polarization state of the laser beam L1. A phase difference plate 33, a condenser lens 34 that condenses the laser light L1 as excitation light EL onto the phosphor 41 and takes out the fluorescence FL from the phosphor 41 as a substantially parallel light beam, and generates fluorescence FL from the excitation light EL. Polarized light that aligns the polarization direction of the illumination light L2 emitted from the polarization dichroic mirror 32, the phosphor wheel 35 having the phosphor 41, the composite fly-eye optical system 36 that equalizes the intensity of the excitation light EL and the fluorescence FL The conversion part 37 and the field lens 38 which adjusts the incident angle of the illumination light L2 to the reflective liquid crystal element 23 are provided. That is, the polarization dichroic mirror 32 corresponds to a beam splitter that is disposed in the optical path between the excitation light source (laser array 51 described later) and the phosphor 41 and branches the fluorescence FL from the optical path of the excitation light EL.

The polarization beam splitter (PBS) 22 is a polarization separation type beam splitter. The polarization beam splitter 22 is formed by bonding a pair of right-angle prisms. On the bonding surface, the illumination light L2 that is linearly polarized light in a predetermined direction incident from the light source device 21 is selected on the inclined surface of one right-angle prism. A polarization separation surface 22a made of a polarization separation film that reflects light is formed. Thereby, the illumination light L <b> 2 emitted from the light source device 21 can be reflected and incident on a reflective liquid crystal element 23 described later. Further, the image light L 3 reflected by the reflective liquid crystal element 23 can be transmitted and incident on the projection optical system 24. The polarization separation surface 22a reflects S-polarized light based on this and transmits P-polarized light.

The reflective liquid crystal element 23 is a display panel that forms the image light L3, that is, an image display element. In particular, the reflective liquid crystal element 23 is a light valve or spatial light in that the image light L3 is formed from the illumination light L2 by changing the spatial reflectance. It can be said that it is a modulation element. The reflective liquid crystal element (image display element) 23 includes an image display panel that is a plate-like electronic component. The reflection type liquid crystal element 23 is a micro display also called LCOS (Liquid crystal on silicon), in which a circuit is directly formed on the surface of a silicon chip and a liquid crystal layer is sandwiched between a counter substrate. When a voltage corresponding to a drive signal is applied to the liquid crystal layer for each pixel, the reflective liquid crystal element 23 modulates the illumination light L2 by changing the arrangement of liquid crystal molecules, and displays a desired image by reflection. Is. At this time, when S-polarized light with the polarization separation surface 22a as a reference is incident on the reflective liquid crystal element 23 as illumination light L2, P-polarized light with the polarization separation surface 22a as a reference is reflected as video light L3.

Although the detailed description is omitted, the projection optical system 24 enlarges an image obtained from the reflective liquid crystal element 23 as an image display element and projects it on a screen or other projection target (not shown). The projection optical system 24 includes a plurality of lens groups and reflecting surfaces, and focusing and zooming can be performed by moving some lens groups in the optical axis SX direction.

The video drive circuit 25 is a circuit portion for operating the reflective liquid crystal element 23 and the drive unit 39 of the phosphor wheel 35 based on video signals input from various content sources (not shown) including terminal devices such as computers. It is. The video drive circuit 25 operates based on a control signal from the control circuit 28, and outputs a drive signal corresponding to the video signal to the reflective liquid crystal element 23 to perform an image display operation. At this time, the video drive circuit 25 monitors the rotational position of the phosphor wheel 35 and makes the display operation of the reflective liquid crystal element 23 correspond to the rotational position of the phosphor wheel 35. As will be described in detail later, the phosphor wheel 35 is formed with a plurality of regions that emit fluorescence having different wavelengths in the circumferential direction, and the video drive circuit 25 serving as the control unit rotates the phosphor wheel 35. In synchronization, the image displayed on the reflective liquid crystal element 23 corresponding to the wavelength of fluorescence emitted from a plurality of regions is switched. As a result, the reflective liquid crystal element 23 performs a display operation in synchronization with blue light, green light, and red light sequentially emitted from the phosphor wheel 35, thereby enabling projection of a desired color image.

Hereinafter, the components, functions, operations, and the like of the light source device 21 will be described.
First, the laser beam forming unit 31 includes a laser array 51, a collimator array 52, and a beam reduction lens 53. Here, the laser array 51 is an excitation light source for the phosphor 41 and also an illumination light source for blue. The laser array (excitation light source) 51 is configured by two-dimensionally arranging laser diodes (hereinafter also referred to as LDs) that emit blue laser light L1, and emits light with a uniform polarization direction. To do. The laser beam L1 emits P-polarized light with the polarization dichroic mirror 32 as a reference. The collimator array 52 includes a number of lens elements corresponding to the number of LDs constituting the laser array 51. The collimator array 52 converts the laser light L1 emitted from each LD constituting the laser array 51 into a substantially parallel light beam. The beam reduction lens 53 is an afocal system in which a positive lens and a negative lens are combined, and the laser beam L1 is left as a substantially parallel beam, the beam diameter is decreased, and the excitation beam EL having a desired cross-sectional area is obtained.

The polarization dichroic mirror 32 functions as a polarization separation mirror that transmits P-polarized light and selectively reflects S-polarized light, and transmits blue light and selectively reflects green light and red light having longer wavelengths. It has a function as a dichroic mirror. The polarization dichroic mirror 32 is used in combination with the phase difference plate 33, and branches blue light, which is polarized light in a specific direction, in an optical path according to transmission and reflection. The polarization dichroic mirror 32 is formed by forming a dielectric multilayer film 32a on one side of a parallel plate. The polarization dichroic mirror 32 transmits the excitation light EL from the laser beam forming unit 31 as it is, and blue light and green light from the phosphor 41 side. , And red light are reflected to the field lens 38 side. Specifically, the polarization dichroic mirror 32 transmits the excitation light EL that is P-polarized light, is reflected by the phosphor wheel 35, and reflects blue light converted to S-polarized light by reciprocating the phase difference plate 33. To the polarization conversion unit 37. Further, the polarization dichroic mirror 32 reflects the green light and the red light generated by the phosphor 41 when illuminated with the excitation light EL and guides them to the polarization conversion unit 37.

The retardation film 33 is a quarter wave plate made of a birefringent material. The phase difference plate 33 transmits the P-polarized excitation light EL that has passed through the polarization dichroic mirror 32 to change from P-polarized light to circularly-polarized light. Further, the phase difference plate 33 transmits the blue light that has returned from the phosphor 41 side, that is, the excitation light EL, and changes from circularly polarized light to S-polarized light. Thus, the blue light, that is, the excitation light EL that has returned from the phosphor 41 side through the phase difference plate 33 is almost reflected by the polarization dichroic mirror 32 and efficiently guided to the polarization conversion unit 37.

The condenser lens 34 condenses the laser light L1 that has passed through the polarization dichroic mirror 32 on the phosphor 41 as excitation light EL. The condenser lens 34 collects green light and red light generated by the phosphor 41 and guides them to the polarization dichroic mirror 32. The condenser lens 34 also has a role of collecting excitation light EL, that is, blue light reflected by a later-described scattering surface provided along with the phosphor 41 and guiding it to the polarization dichroic mirror 32. The condenser lens 34 is not limited to being constituted by a single lens but can be constituted by a plurality of lenses.

As shown in FIG. 2, the phosphor wheel 35 is obtained by fixing an annular phosphor 41 on a disk-shaped substrate 35a, and is driven around the axis RX by being driven by the drive unit 39 shown in FIG. Rotates at high speed. The phosphor 41 emits fluorescence having a longer wavelength by absorption of the excitation light EL. The phosphor 41 has a green area AR1 that generates green fluorescence when irradiated with the excitation light EL, a red area AR2 that generates red fluorescence when irradiated with the excitation light EL, and a scattering surface that reflects and reflects the excitation light EL slightly. It has a certain blue area AR3. In the blue region AR3, it is desirable not to change the polarization state so much.

The fly's eye optical system 36 includes a first homogenizing system 36a that equalizes the intensity distribution of the excitation light EL and a second homogenizing system 36b that equalizes the intensity distribution of the fluorescence FL. The first homogenization system 36a for the excitation light EL includes a first fly-eye lens 61 disposed on the laser array (excitation light source) 51 side of the polarization dichroic mirror 32, and between the polarization dichroic mirror 32 and the phosphor 41. And a second fly-eye lens 62 disposed in the optical path. The second homogenization system 36b for the fluorescence FL is disposed on the side where the fluorescence FL of the second fly-eye lens 62 disposed in the optical path between the polarization dichroic mirror 32 and the phosphor 41 and the polarization dichroic mirror 32 is emitted. And a third fly-eye lens 63 disposed. That is, the second fly's eye lens 62 is also used to make the intensity distribution of both the excitation light EL and the fluorescence FL uniform. The first fly-eye lens 61 contributes to the uniform distribution of the intensity of the excitation light EL, and the third fly-eye lens 63 contributes to the uniform distribution of the intensity distribution of the fluorescent light FL and the blue reflected excitation light. As shown in FIG. 3A, the first fly-eye lens 61 includes a plurality of lenses 61a as elements for dividing the excitation light EL. As shown in FIG. 3B, the second fly-eye lens 62 includes a plurality of lenses 62a as elements for appropriately diverging the excitation light EL and dividing the fluorescence FL. As shown in FIG. 3C, the third fly-eye lens 63 includes a plurality of lenses 63a as elements for appropriately diverging the fluorescence FL and the like. The lens 61a constituting the first fly-eye lens 61, the lens 62a constituting the second fly-eye lens 62, and the lens 63a constituting the third fly-eye lens 63 are two-dimensionally arranged adjacent to each other. .

The homogenization of the intensity distribution of the excitation light EL by the first homogenization system 36a will be described. The excitation light EL enters the first fly's eye lens 61 and is divided into a plurality of light beams. The excitation light ELa emitted from one lens 61a constituting the first fly-eye lens 61 is converged by the lens 61a. The excitation light ELa from the lens 61a enters the corresponding lens 62a of the second fly-eye lens 62 and enters the condenser lens 34 while diverging. The condenser lens 34 causes the excitation light ELa from each lens 62 a constituting the second fly-eye lens 62 to be incident on the rectangular effective area of the phosphor 41 so as to be superimposed with a small deviation. As a result, the rectangular effective area of the phosphor 41 is illuminated without waste by the uniform excitation light ELa, that is, the excitation light EL. Note that the second fly's eye lens 62 can have not only a function of changing the divergence angle of the excitation light ELa but also a function of adjusting the emission direction of the excitation light ELa.

The homogenization of the intensity distribution of the fluorescence FL and the blue light (reflection excitation light) by the second homogenization system 36b will be described. In addition, since blue light (reflected excitation light) is equalized similarly to fluorescence FL, the description is abbreviate | omitted by description of fluorescence FL below. Each of the lenses 62 a constituting the second fly-eye lens 62 has a shape substantially similar to the image display area of the reflective liquid crystal element 23. In FIG. 3B, the lenses 62a are arranged in a matrix, but may be arranged in a staggered manner. The fluorescent light collimated by the condenser lens 34 enters the second fly-eye lens 62 from the opposite direction to the excitation light EL and is divided into a plurality of light beams. The fluorescence FLa emitted from one lens 62a constituting the second fly's eye lens 62 is converged by the lens 62a. The fluorescent light FLa from the lens 62a enters the corresponding lens 63a of the third fly's eye lens 63 to once form a secondary light source and enter the polarization conversion unit 37 while being appropriately diverged. Note that the third fly's eye lens 63 can have not only a function of changing the divergence angle of the fluorescence FLa but also a function of adjusting the emission direction of the fluorescence FLa.

As described above, the laser array (excitation light source) 51 emits blue light as the excitation light EL, the phosphor 41 emits fluorescence generated by excitation with blue light, and the fly-eye optical system 36 generates excitation light. The EL intensity distribution and the fluorescence FL intensity distribution are made uniform. Thereby, the illumination light L2 containing blue light and fluorescence FL can be obtained.

The polarization conversion unit 37 is arranged on the light exit side of the third fly-eye lens 63, and aligns the polarization direction of the illumination light L2 obtained from the excitation light EL. Thereby, the polarization direction of the illumination light L2 can be aligned in a desired direction and can be incident on the reflective liquid crystal element 23, which is an illumination target, specifically, a light modulation element or the like. The polarization conversion unit 37 is a combination of a plurality of conversion units including, for example, a polarization beam splitter and a wave plate, and is P-polarized light among S-polarized light and P-polarized light included in the fluorescent light FLa and blue light reflected by the polarization dichroic mirror 32. Are selectively converted to S-polarized light. As a result, substantially S-polarized fluorescence FL (that is, green light and red light) can be made incident on the polarization beam splitter 22, and the loss of the light source light is reduced. Note that the blue light (reflected excitation light) obtained from the excitation light EL is only the S-polarized light component reflected by the polarization dichroic mirror 32 and passes through the polarization conversion unit 37 almost as it is.

The field lens 38 is for harmonizing the traveling direction of light beams in a region close to the optical axis SX and a region away from the optical axis SX on the reflective liquid crystal element 23, and illumination light on the reflective liquid crystal element 23. L2 is uniformly superimposed and has a function of making the incident angle range of the illumination light L2 uniform.

According to the light source device 21 of the first embodiment described above, the second fly's eye lens 62 that is a part of the fly's eye optical system 36 is disposed in the optical path between the polarization dichroic mirror 32 and the phosphor 41. Thus, the excitation light EL and the fluorescence FL are passed twice. The effective area of the phosphor 41 can be uniformly illuminated by the excitation light EL by the first homogenizing system 36a including the second fly-eye lens 62. Further, the second uniformizing system 36b including the second fly-eye lens 62 can uniformly illuminate the reflective liquid crystal element 23 by uniformizing the intensity distribution of the fluorescence FL. A second fly-eye lens 62, which is a part of the fly-eye optical system 36, is disposed in the optical path between the polarization dichroic mirror 32 and the phosphor 41, and is also used to equalize the intensity distribution of both the excitation light EL and the fluorescence FL. Therefore, the size and cost of the optical system of the light source device 21 can be reduced as compared with the case where the fly-eye optical system for excitation light and the fly-eye optical system for fluorescence are provided separately.

Further, as described above, the projection device 2 uses the small and efficient light source device 21 and can be small and bright.

[Second Embodiment]
The light source device according to the second embodiment will be described below. The light source device according to the second embodiment is a modification of the light source device according to the first embodiment, and matters not specifically described are the same as those in the first embodiment.

As shown in FIG. 4A, in the case of the light source device 21 of the second embodiment, the laser array 151 generates, for example, light of 440 nm or less (ultraviolet light or blue-violet light) as the excitation laser light L1.

As shown in FIG. 4B, in the phosphor wheel 35, the phosphor 141 includes a green region AR1 that generates green fluorescence when irradiated with the excitation light EL, a red region AR2 that generates red fluorescence when irradiated with the excitation light EL, A blue region AR3 that generates blue fluorescence having a wavelength longer than that of the excitation light EL when irradiated with the excitation light EL.

In the second embodiment described above, instead of the polarization dichroic mirror 32, a dichroic mirror 132 that transmits excitation light EL in the ultraviolet or blue-violet wavelength band and selectively reflects visible light having a longer wavelength is used. ing. The dichroic mirror 132 is a color separation type beam splitter. In this case, it is not necessary to control the polarization state of the excitation light EL or the like, and the phase difference plate 33 shown in FIG. 1 is not necessary. Here, the dichroic mirror 132 is disposed in the optical path between the excitation light source (laser array 151) and the phosphor 141, and corresponds to a beam splitter that branches the fluorescence FL from the optical path of the excitation light EL.

[Third Embodiment]
The projector according to the third embodiment will be described below. The projection apparatus according to the third embodiment is a modification of the projection apparatus according to the first embodiment, and matters not specifically described are the same as those in the first embodiment.

As shown in FIG. 5, the light source device 21 of the third embodiment has a fly-eye optical system 136 in which a fly-eye lens 162 is disposed only in the optical path between the polarization dichroic mirror 32 and the phosphor 41. As a result, the fly-eye optical system 136 can be arranged in a smaller space, and the light source device 21, and thus the projection device 2, can be further downsized. The fly-eye lens 162 is used to make the intensity distribution of both the excitation light EL and the fluorescence FL uniform, and includes a plurality of lenses 162a as elements for dividing the excitation light EL and the fluorescence FL.

The array surface 62i on the laser array 51 side of the fly-eye lens 162 has the same function as the first fly-eye lens 61 of the first embodiment with respect to the excitation light EL, and divides the excitation light EL. The array surface 62o on the phosphor 41 side of the fly-eye lens 162 has the same function as the second fly-eye lens 62 of the first embodiment with respect to the excitation light EL, and appropriately divides the divided excitation light ELa. Let The array surface 62o on the phosphor 41 side of the fly-eye lens 162 may have not only a function of changing the divergence angle of the divided excitation light ELa but also a function of adjusting the emission direction of the excitation light ELa. it can.

The array surface 62o on the phosphor 41 side of the fly-eye lens 162 has the same function as the second fly-eye lens 62 of the first embodiment with respect to the fluorescence FL, and divides the fluorescence FL. The array surface 62i on the laser array 51 side of the fly-eye lens 162 has a function similar to that of the third fly-eye lens 63 of the first embodiment with respect to the fluorescence FL, and appropriately divides the divided fluorescence FLa.

5 does not have the polarization conversion unit 37. The light source device 21 shown in FIG. Therefore, in the case of the third embodiment, a digital micromirror device 123 is used instead of the polarization beam splitter 22 and the reflective liquid crystal element 23. Note that a projection optical system that enlarges an image obtained from the digital micromirror device 123 and projects it on a screen or the like is not shown. In FIG. 5, a single fly-eye lens having lens surfaces formed on both sides is disposed. However, the present invention is not limited to this, and a plurality of fly-eye lenses may be disposed.

The digital micromirror device 123 is a two-dimensional array of a large number of mirrors that correspond to pixels and can be tilted, and projects illumination light L2 incident from the polarization dichroic mirror 32 via the field lens 38 (not shown). An on / off operation that is directed toward the optical system or deviates from the projection optical system is possible.

Although the light source device and the projection device according to the embodiment have been described above, the light source device and the like according to the present invention are not limited to the above. For example, the specific configurations of the light source device 21 and the projection optical system 24 are not limited to those shown in the drawings, and can be changed as appropriate according to the application.

For example, in the laser beam forming unit 31, an LED array can be used instead of the laser array 51. When using light from the LED array as illumination light, it is desirable to align the polarization direction of the light from the LED array before entering the polarization dichroic mirror 32.

Further, the condenser lens 34, the second fly-eye lens 62, the

phosphors

41, 141, and the like can be provided on the reflection side of the polarization dichroic mirror 32. In this case, the polarization dichroic mirror 32 reflects the excitation light EL that is S-polarized light, and transmits green light, red light, and the like generated by the

phosphors

41 and 141 illuminated by the excitation light EL.

As the image display element, a transmissive liquid crystal element may be used instead of the reflective liquid crystal element 23.

In the phosphor 41 or the phosphor wheel 35, the blue region AR3 can be a simple reflecting surface instead of a scattering surface. In this case, for example, a method of diffusing light with the collimator array 52 incomplete is used. Can do.

Claims

An excitation light source that emits excitation light;
A phosphor that emits fluorescence when irradiated with excitation light; and
A beam splitter that is arranged in an optical path between the excitation light source and the phosphor, and branches the fluorescence from the optical path of the excitation light;
A fly-eye optical system that equalizes the intensity distribution of excitation light and the intensity distribution of fluorescence, and at least part of the fly-eye optical system is disposed in an optical path between the beam splitter and the phosphor A light source device for a projection device.
The fly-eye optical system includes a first fly-eye lens disposed on the excitation light source side of the beam splitter, a second fly-eye lens disposed in an optical path between the beam splitter and the phosphor, The light source device for a projection device according to claim 1, further comprising a third fly's eye lens disposed on a beam splitter side on which the fluorescence is emitted.
The light source device for a projection device according to claim 2, further comprising a polarization conversion unit that is disposed on a light exit side of the third fly-eye lens and aligns the polarization direction.
The light source device for a projection device according to claim 1, wherein the fly-eye optical system is disposed only in an optical path between the beam splitter and the phosphor.
The excitation light source emits blue light as excitation light, the phosphor emits fluorescence generated by excitation with blue light, and the fly-eye optical system performs excitation light intensity distribution and fluorescence intensity distribution. The light source device for a projection device according to any one of claims 1 to 4, wherein each of the light source devices is uniformized.
The beam splitter is a polarization dichroic mirror that is used in combination with a phase difference plate and splits blue light, which is polarized light in a specific direction, on the optical path depending on whether it is transmitted or reflected, and converts the blue light from the excitation light source into the fluorescent light. 6. The light source device for a projection device according to claim 5, wherein the light source device for the projection device according to claim 5, wherein the light source device guides blue light that has not been used for excitation by the phosphor to a fluorescent light path.
The excitation light source emits ultraviolet light or blue-violet light as excitation light, the phosphor emits fluorescence in the visible range, and the fly-eye optical system performs excitation light intensity distribution and fluorescence intensity distribution, respectively. The light source device for a projection device according to any one of claims 1 to 4, wherein the light source device is uniformized.
A light source device for a projection device according to any one of claims 1 to 7,
An image display element illuminated by the light source device;
A projection optical system for projecting an image formed by the image display element;
A projection apparatus.
The light source device includes a phosphor wheel in which the phosphor is fixed to a disk-shaped substrate,
The phosphor wheel is formed with a plurality of regions emitting fluorescence of different wavelengths in the circumferential direction,
The projection apparatus according to claim 8, further comprising: a control unit that switches an image displayed on the image display element corresponding to a wavelength of fluorescence emitted from the plurality of regions in synchronization with rotation of the phosphor wheel.