JP2015052804A - Illuminating device and projector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve a simple structure and a small size and to emit high quality fluorescence by restricting deterioration of a fluorescent body.SOLUTION: The illuminating device comprises a solid light source 11 configured to emit blue light; a fluorescent body 13b configured to convert blue light into fluorescent light; a liquid crystal display element 30 configured to generate image light by modulating the fluorescent light with an image signal; a projecting optical system 50 configured to project image light; a rotary fluorescent plate 13 on which the fluorescent body 13b is continuously formed along a circumferential direction of a disk 13a; a motor 14 configured to rotate the rotary fluorescent plate 13 around a rotary shaft; a light emission timing generator 101 configured to generate a light emission timing signal that has a period synchronized with a frame period of the image signal; a rotation period determining part 102 configured to determine a rotation period that is not an integral multiple of the period of the light emission timing signal; a motor driving part 63 configured to drive the motor 14, thereby rotating the rotary fluorescent plate 13 so as to match the rotation period; and a light source drive part 62 configured to cause the solid light source 11 to intermittently emit light at the period of the light emission timing signal.

Description

  The present invention relates to a lighting device and a projector.

There is known a projector that excites a phosphor with light emitted from a light source to develop fluorescence, obtains red light, blue light, and green light and uses them for image light (see, for example, Patent Document 1).
The projection device (projector) disclosed in this document includes a phosphor wheel in which three fan-shaped phosphors that emit red, blue, and green fluorescence are divided and arranged circumferentially. The projection device rotates the phosphor wheel in the circumferential direction, and sequentially irradiates the three fan-shaped phosphors with the laser light emitted from the light source to obtain red light, blue light, and green light to obtain an image. Used for light.

Increasing the output level of the laser light emitted from the light source to the phosphor increases the brightness of the fluorescence generated by the phosphor, while increasing the temperature of the irradiated portion of the phosphor and promoting the deterioration of the phosphor.
Therefore, the projector disclosed in the same document shifts the position of the rotating phosphor wheel itself in the radial direction to shift the position on the phosphor irradiated with the laser light, thereby reducing the thermal damage of the phosphor. ing.

JP 2010-164846 A

However, the projection apparatus disclosed in this document requires a second motor that operates the crank mechanism to reciprocate the phosphor wheel in the radial direction in addition to the first motor that rotates the phosphor wheel. For this reason, the structure is complicated and hinders downsizing of the projection apparatus.
Accordingly, the present invention has been made to solve the above-described problem, and can be realized in a small size with a simple structure, and further can suppress deterioration of the phosphor and emit high-quality fluorescence. And to provide a projector.

[1] In order to solve the above problems, an illumination device according to one embodiment of the present invention includes a solid-state light source that emits excitation light, a phosphor that converts the excitation light into fluorescence, and a circumferential direction of a circle on a flat plate A fluorescent plate on which the phosphor is continuously formed, a motor unit that rotates the fluorescent plate around an axis that passes through the center of the circle, and a light emission that generates a light emission timing signal having a period synchronized with a frame period. A timing generation unit; a rotation cycle determination unit that determines a rotation cycle that is a non-integer multiple of the cycle of the light emission timing signal; and a motor drive unit that drives the motor unit to match the rotation cycle of the fluorescent screen with the rotation cycle. And a light source driving unit that causes the solid-state light source to emit light intermittently at a cycle of the light emission timing signal.
With this configuration, in the first aspect of the present invention, the irradiation position of the excitation light in the phosphor constantly moves, so that the temperature rise of the phosphor irradiation portion can be suppressed, and the phosphor is deteriorated. It can be made very slow, so that high quality fluorescence can be obtained. In addition, the first aspect of the present invention has a configuration in which the irradiation position of the excitation light to the phosphor is shifted using a single motor unit, and thus can be realized in a small size with a simple structure.
[2] The illumination device according to [1], wherein the rotation period determination unit determines a rotation period that is a non-integer times a period of the light emission timing signal.
With this configuration, even in the second aspect of the present invention, the irradiation position of the excitation light in the phosphor always moves, so that the temperature rise of the phosphor irradiation portion can be suppressed, and the phosphor is deteriorated. It can be made very slow, so that high quality fluorescence can be obtained.
[3] In the illumination device according to [1] or [2], the light source driving unit has an output level adjustment function of the solid-state light source, and includes a light detection unit that detects the fluorescence, and a light detection unit. A light source output level adjusting unit that controls the output level adjusting function of the light source driving unit according to a detection result, and the light source driving unit is configured to control the output level adjusting function from the solid-state light source. The output level of the excitation light is corrected.
With this configuration, in the third aspect of the present invention, it is possible to obtain higher-quality fluorescence while suppressing variations in the amount of light emitted from the phosphor.
[4] The illumination device according to any one of [1] to [3], wherein the solid-state light source emits blue light, and the phosphor emits part of the blue light as red light. While converting into green light, another part of the blue light is transmitted.

[5] In order to solve the above-described problem, a projector according to one embodiment of the present invention includes a solid-state light source that emits excitation light, a phosphor that converts the excitation light into fluorescence, and modulates the fluorescence with an image signal. A light modulation unit that generates image light, a projection optical system that projects the image light, a fluorescent plate on which the phosphor is continuously formed along the circumferential direction of a circle on a flat plate, and the center of the circle A motor unit that rotates the fluorescent plate around a penetrating axis; a light emission timing generation unit that generates a light emission timing signal having a period synchronized with a frame period of the image signal; and a rotation that is a non-integer multiple of the period of the light emission timing signal A rotation cycle determination unit that determines a cycle; a motor drive unit that drives the motor unit to match the rotation cycle of the fluorescent screen with the rotation cycle; and the solid-state light source between the light emission timing signals. It characterized in that it comprises a light source driving unit for emitting, to the.
With this configuration, in the fifth aspect of the present invention, since the irradiation position of the excitation light in the phosphor constantly moves, it is possible to suppress the temperature rise of the irradiated portion of the phosphor, and to deteriorate the phosphor. It can be made very slow, so that high quality fluorescence can be obtained. Further, in the fifth aspect of the present invention, since the irradiation position of the excitation light to the phosphor is shifted using a single motor unit, it can be realized with a simple structure and a small size.
[6] The projector according to [5], wherein the rotation period determination unit determines a rotation period that is a non-integer times one of the period of the light emission timing signal.
With this configuration, even in the sixth aspect of the present invention, the irradiation position of the excitation light in the phosphor always moves, so that the temperature rise of the phosphor irradiation portion can be suppressed, and the phosphor is deteriorated. It can be made very slow, so that high quality fluorescence can be obtained.
[7] In the projector according to [5] or [6], the light source driving unit has an output level adjustment function of the solid-state light source, and a light detection unit that detects the fluorescence, and detection of the light detection unit A light source output level adjusting unit that controls the output level adjusting function of the light source driving unit according to a result, wherein the light source driving unit performs the excitation from the solid light source according to the control of the output level adjusting function The light output level is corrected.
With this configuration, in the seventh aspect of the present invention, it is possible to emit higher-quality fluorescence while suppressing variations in the amount of light emitted from the phosphor.
[8] In the projector according to any one of [5] to [7], the solid-state light source emits blue light, and the phosphor converts part of the blue light into red light and green light. The light is converted into light, and another part of the blue light is transmitted.

  Therefore, according to each aspect of the present invention, it is possible to realize a small size with a simple structure, and furthermore, it is possible to emit high-quality fluorescence while suppressing deterioration of the phosphor.

1 is a schematic diagram schematically illustrating an overall configuration of a projector according to a first embodiment of the invention. It is a figure showing the structure of the rotation fluorescent screen provided in a projector. It is a figure showing the optical characteristic of the fluorescent substance provided in a rotation fluorescent plate. It is a block diagram showing the functional structure of the control system which controls operation | movement of the projector which is the same embodiment. It is a flowchart showing the procedure of the process which the control system of the projector which is the same embodiment performs. It is a block diagram showing the functional structure of the control system which controls operation | movement of the projector which is 2nd Embodiment of this invention. It is a flowchart showing the procedure of the process which the control system of the projector which is the same embodiment performs. 4 is a timing chart showing timings of various signals generated by the projector in the embodiment. 4 is a timing chart showing timings of various signals generated by the projector in the embodiment.

Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings.
[First Embodiment]
FIG. 1 is a schematic diagram schematically showing the overall configuration of the projector according to the first embodiment of the invention.
As shown in FIG. 1, the projector 1 includes an illumination device 10, a color separation light guide optical system 20, liquid crystal display elements 30 </ b> R, 30 </ b> G, and 30 </ b> B, a cross dichroic prism 40, and a projection optical system 50. In the following description, the liquid crystal display elements 30R, 30G, and 30B may be collectively referred to as the liquid crystal display element 30.
The projector 1 displays an image on the screen SCR by projecting image light based on an image signal supplied from the outside toward the screen SCR.

  The illumination device 10 emits white light whose illumination optical axis is the optical axis AX. This white light is the light that is the basis of the image light. The illumination device 10 includes a solid-state light source 11, a condensing optical system 12, a rotating fluorescent plate 13, a motor 14, a collimator optical system 15, a first lens array 16, a second lens array 17, and a polarization conversion element. 18 and a superimposing lens 19.

The solid light source 11 emits blue laser light (hereinafter also simply referred to as blue light) as excitation light, for example. This blue laser light has a characteristic that a peak of emission intensity appears at a wavelength of about 445 nm (nanometer) or about 460 nm. In the present embodiment, the solid light source 11 will be described as an example that emits blue laser light in which a peak of emission intensity appears at a wavelength of about 445 nm.
As the solid light source 11, for example, a light source including a single semiconductor laser element or a light source including a plurality of semiconductor laser elements arranged in a planar shape is used.

The condensing optical system 12 includes a single lens or a plurality of lenses, for example, a first lens 12 a and a second lens 12 b, and is provided on an optical path between the solid light source 11 and the rotating fluorescent plate 13. The condensing optical system 12 condenses the blue light emitted from the solid light source 11 at a predetermined position of the rotating fluorescent plate 13.
The rotating fluorescent plate 13 is rotatably supported by a motor 14 and converts part of the blue light collected by the condensing optical system 12 into fluorescent light including red light and green light. And emits red light and green light. Details of the rotating fluorescent plate 13 will be described later.

The motor 14 is an electric motor that rotates the rotating fluorescent plate 13. The motor 14 takes in a rotation instruction signal supplied from a motor driving unit, which will be described later, and rotates the rotation shaft at a rotation cycle corresponding to the rotation instruction signal. The motor 14 includes a position detection sensor realized by, for example, a Hall element, and outputs position information indicating the reference position of the rotation axis detected by the position detection sensor.
The collimator optical system 15 includes a single lens or a plurality of lenses, for example, a first lens 15a and a second lens 15b, and substantially collimates light coming from the rotating fluorescent plate 13.

The first lens array 16 has a plurality of microlenses 16a arranged two-dimensionally, and divides the light substantially collimated by the collimator optical system 15 into a plurality of partial light beams. Specifically, the first lens array 16 is provided so that the plurality of microlenses 16a are two-dimensionally arranged in a plane orthogonal to the optical axis AX.
Note that the outer shape of the plurality of microlenses 16a included in the first lens array 16 is substantially similar to the outer shape of the image forming regions of the liquid crystal display elements 30R, 30G, and 30B.

  The second lens array 17 includes a plurality of microlenses 17 a corresponding to the plurality of microlenses 16 a included in the first lens array 16. That is, the second lens array 17 is provided such that a plurality of microlenses 17a corresponding to the plurality of microlenses 16a are two-dimensionally arranged in a plane orthogonal to the optical axis AX. The second lens array 17 forms an image formed by the micro lenses 16a included in the first lens array 16 together with the superimposing lens 19 in the vicinity of the image forming regions of the liquid crystal display elements 30R, 30G, and 30B.

  The polarization conversion element 18 includes a polarization separation layer, a reflection layer, and a phase difference plate (all of which are not shown), and each partial light beam divided by the first lens array 16 is converted into a polarization direction. It is emitted as almost one type of linearly polarized light. The polarization separation layer transmits one linearly polarized light component of the polarized light components included in the light coming from the rotating fluorescent plate 13 as it is, and reflects the other linearly polarized light component in a direction perpendicular to the optical axis AX. The reflective layer reflects the other linearly polarized light component reflected by the polarization separation layer in a direction parallel to the optical axis AX. The phase difference plate converts the other linearly polarized light component reflected by the reflective layer into the one linearly polarized light component.

  The superimposing lens 19 is arranged so that the optical axis thereof coincides with the optical axis AX of the illumination device 10. The superimposing lens 19 condenses each partial light beam coming from the polarization conversion element 18 to the liquid crystal display elements 30R, 30G, 30B. Superimpose in the vicinity of the image forming area. The first lens array 16, the second lens array 17, and the superimposing lens 19 described above constitute a lens integrator optical system that uniformizes light coming from the solid light source 11.

The color separation light guide optical system 20 separates light coming from the illumination device 10 into red light, green light, and blue light, and guides each color light to the liquid crystal display elements 30R, 30G, and 30B, respectively.
The color separation light guide optical system 20 includes dichroic mirrors 21 and 22, reflection mirrors 23 to 25, relay lenses 26 and 27, and condensing lenses 28R, 28G, and 28B.

  The dichroic mirrors 21 and 22 are mirrors in which a wavelength selective transmission film that reflects light in a predetermined wavelength region and transmits light in a wavelength region other than the predetermined wavelength region is formed on a transparent substrate. Specifically, the dichroic mirror 21 transmits red light and reflects green light and blue light, and the dichroic mirror 22 reflects green light and transmits blue light.

The reflection mirror 23 is a mirror that reflects red light.
The reflection mirrors 24 and 25 are mirrors that reflect blue light.
The relay lens 26 is provided between the dichroic mirror 22 and the reflection mirror 24.
The relay lens 27 is provided between the reflection mirror 24 and the reflection mirror 25. These relay lenses 26 and 27 are provided in order to prevent and suppress a decrease in light use efficiency due to light divergence and the like because the optical path length of blue light is longer than the optical path lengths of other color lights.
The condensing lenses 28R, 28G, and 28B convert the red light reflected by the reflection mirror 23, the green light reflected by the dichroic mirror 22, and the blue light reflected by the reflection mirror 25 into the liquid crystal display elements 30R, 30G. , 30B, respectively.

  The red light that has passed through the dichroic mirror 21 is reflected by the reflecting mirror 23, passes through the condenser lens 28R, and enters the image forming region of the liquid crystal display element 30R. The green light reflected by the dichroic mirror 21 is reflected by the dichroic mirror 22, passes through the condenser lens 28G, and enters the image forming area of the liquid crystal display element 30G. Further, the blue light reflected by the dichroic mirror 21 and passing through the dichroic mirror 22 passes through the relay lens 26, the reflection mirror 24, the relay lens 27, the reflection mirror 25, and the condenser lens 28B in this order, and the liquid crystal display element 30B. Incident on the image forming area.

The liquid crystal display elements 30R, 30G, and 30B modulate incident red light, green light, and blue light based on an image signal supplied from the outside, and red image light, green image light, and blue image light. And generate respectively.
Although not shown in FIG. 1, incident-side polarizing plates are interposed between the condenser lenses 28R, 28G, and 28B and the liquid crystal display elements 30R, 30G, and 30B, and the liquid crystal display element 30R. , 30G, 30B and the cross dichroic prism 40, the exit side polarizing plates are respectively disposed.

  The liquid crystal display elements 30R, 30G, and 30B are transmissive display elements in which liquid crystal is hermetically sealed between a pair of transparent glass substrates, and include, for example, a polysilicon TFT (Thin Film Transistor) as a switching element. Is. The liquid crystal display elements 30R, 30G, and 30B modulate the polarization directions of the red light, the green light, and the blue light (all of which are linearly polarized light) that have passed through the incident-side polarizing plate by the switching operation of the switching element based on the image signal. Thus, red image light, green image light, and blue image light are generated.

  The cross dichroic prism 40 combines the red image light, the green image light, and the blue image light that come from each of the exit-side polarizing plates to form color image light based on the three primary colors of light. Specifically, the cross dichroic prism 40 is an optical member formed by bonding four right-angle prisms into a cube. A dielectric multilayer film is formed on the X-shaped interface where the right-angle prisms are bonded together. The dielectric multilayer film formed on one X-shaped interface reflects red light, and the dielectric multilayer film formed on the other interface reflects blue light. The cross dichroic prism 40 synthesizes red light, green light, and blue light by aligning red light and blue light whose traveling directions are changed by these dielectric multilayer films with the traveling direction of transmitted green light. .

  The projection optical system 50 enlarges and projects the color image light synthesized by the cross dichroic prism 40 toward the screen SCR.

FIG. 2 is a diagram illustrating the configuration of the rotating fluorescent plate 13 provided in the projector 1. FIG. 4A is a front view of the rotating fluorescent plate 13, and FIG. 4B is a cross-sectional view taken along the line AA in FIG.
As shown in FIGS. 4A and 4B, the rotating fluorescent plate 13 is formed by placing a phosphor 13b as a single fluorescent layer on one surface of a disc 13a that is a light-transmitting substrate. It is formed continuously along the circumferential direction.

  The circular plate 13a is formed using a material that transmits blue light, such as quartz glass, crystal, sapphire, optical glass, and transparent resin. A hole through which the rotation shaft of the motor 14 passes is formed at the center of the circle of the disk 13a. In addition, although the example using the disk 13a as a board | substrate was demonstrated here, the shape of a board | substrate is not limited to a disk, What is necessary is just a flat plate.

The phosphor 13b has a property of converting part of the blue light coming from the solid light source 11 into fluorescence including red light and green light and allowing the other part of the blue light to pass through. As the phosphor 13b, for example, a phosphor containing (Y, Gd) ₃ (Al, Ga) ₅ O ₁₂ : Ce, which is an yttrium aluminum garnet (YAG) phosphor, can be used. As shown in FIG. 2B, the phosphor 13b is formed on one surface of the disk 13a via a dichroic film 13c that transmits blue light and reflects red light and green light.

  FIG. 3 is a diagram illustrating the optical characteristics of the phosphor 13 b provided on the rotating fluorescent plate 13. The figure (a) is a figure showing the spectrum of the blue light which injects into the fluorescent substance 13b, The figure (b) is a figure showing the spectrum of the fluorescence converted with the fluorescent substance 13b. A graph indicated by a symbol B in FIG. 5A is an optical characteristic of blue light emitted from the solid light source 11 as excitation light. In addition, the graph indicated by the symbol R in FIG. 5B is an optical characteristic of a color component that can be used as red light in the fluorescence converted by the phosphor 13b. In addition, the graph indicated by symbol G in FIG. 5B is an optical characteristic of a color component that can be used as green light in the fluorescence converted by the phosphor 13b. In other words, the phosphor 13b formed on the rotating fluorescent plate 13 is a yellow light that includes a part of the blue light B having the spectrum shown in FIG. 9A and the red light R and the green light G shown in FIG. Convert to light (fluorescence).

  The rotating fluorescent plate 13 has the surface on which the phosphor 13b is formed facing away from the side on which the blue light is incident so that the blue light coming from the solid light source 11 is incident on the phosphor 13b from the disc 13a side. Provided. The rotating fluorescent plate 13 is provided in the vicinity of the condensing position of the condensing optical system 12 so that blue light is incident on the region where the phosphor 13b is formed while being rotated by the motor 14.

Next, the configuration of the control system of the projector 1 according to the present embodiment will be described.
FIG. 4 is a block diagram illustrating a functional configuration of a control system that controls the operation of the projector 1. In the figure, only the components necessary for explanation are extracted and simplified from the configurations shown in FIG.
As shown in FIG. 4, the projector 1 includes a control unit 61, a light source driving unit 62, a motor driving unit 63, and an image signal supply unit 64 as a control system.

The control unit 61 is realized by including a CPU (Central Processing Unit), a ROM (Read Only Memory), and a RAM (Random Access Memory) (all of which are not shown). The CPU reads the control program stored in the ROM, expands it in the RAM, and executes the program steps on the RAM. The control unit 61 controls the overall operation of the projector 1 by executing the program by the CPU. The control unit 61 supplies an image output request signal to the image signal supply unit 64 by executing the control program.
The control unit 61 includes a light emission timing generation unit 101 and a rotation cycle determination unit 102 as functional configurations.

  The light emission timing generation unit 101 takes in the frame synchronization signal supplied from the image signal supply unit 64, and uses the light emission timing signal for controlling the emission period of the blue light, which is the excitation light emitted from the solid light source 11, as the frame synchronization signal. The light emission timing signals are generated in synchronization with each other, and the light emission timing signal is supplied to the light source driving unit 62 and the rotation period determining unit 102. The frame synchronization signal is a synchronization signal that determines the frame period of video, and is, for example, a pulse signal having a frame rate of 60 frames / second (fps; frame par second). The light emission timing signal is, for example, a positive active pulse signal synchronized with the frame synchronization signal as described above. That is, for example, when the frame rate of the frame synchronization signal is 60 fps, the light emission timing signal is a positive active pulse signal having a period of 1/60 seconds or 1/120 seconds synchronized with the frame frequency.

The rotation cycle determination unit 102 takes in the light emission timing signal supplied from the light emission timing generation unit 101, calculates the rotation cycle of the rotating fluorescent screen 13 that is asynchronous with the pulse cycle of the light emission timing signal, and the value of this rotation cycle (rotation). (Period value) is supplied to the motor drive unit 63. That is, the rotation cycle determination unit 102 obtains a rotation cycle value that is a non-integer multiple of the pulse cycle of the light emission timing signal and is a fraction of a non-integer, and supplies this rotation cycle value to the motor drive unit 63. .
Further, the rotation cycle determination unit 102 takes in the position information of the rotation axis of the motor 14 supplied from the motor driving unit 63 and determines whether or not the rotation axis of the motor 14 is rotating based on this position information.

  The light source driving unit 62 takes in the light emission timing signal supplied from the light emission timing generation unit 101 of the control unit 61 and causes the solid-state light source 11 to emit light intermittently based on the timing indicated by the light emission timing signal. That is, when the light emission timing signal is a positive active pulse signal, the light source driving unit 62 causes the solid-state light source 11 to emit light during the positive period of the light emission timing signal. In the present embodiment, the level value of the excitation light emitted from the light source driving unit 62 is constant.

  The motor drive unit 63 takes in the rotation cycle value supplied from the rotation cycle determination unit 102 of the control unit 61, generates a rotation instruction signal designating this rotation cycle value, supplies the rotation instruction signal to the motor 14, and drives it. Further, the motor drive unit 63 takes in the position information of the rotating shaft supplied from the motor 14 and supplies the position information to the rotation period determining unit 102.

  The image signal supply unit 64 includes a synchronization signal generation unit (not shown), and supplies the frame synchronization signal generated by the synchronization signal generation unit to the light emission timing generation unit 101 of the control unit 61. The image signal supply unit 64 takes in the image output request signal supplied from the control unit 61 and synchronizes the image signal supplied from the outside with the frame synchronization signal in accordance with the image output request signal. Supply to 30R, 30G, and 30B, respectively.

Next, control of the projector 1 executed by the control system having the above-described configuration will be described.
FIG. 5 is a flowchart illustrating a procedure of processing executed by the control system of the projector 1 according to the present embodiment. When the control unit 61 starts the control program and the synchronization signal generation unit of the image signal supply unit 64 starts generating the frame synchronization signal, the processing according to the flowchart of FIG.

  First, in step S1, the light emission timing generation unit 101 takes in the frame synchronization signal supplied from the image signal supply unit 64, generates a light emission timing signal synchronized with the frame synchronization signal, and determines the rotation period with the light source driving unit 62. To the unit 102. For example, the light emission timing generation unit 101 takes in a frame synchronization signal having a period of 1/60 seconds from the image signal supply unit 64, and emits a light emission timing signal (positive active period) having a period of 1/120 seconds synchronized with the frame synchronization signal. For example, 0.1 / 120 seconds) is generated and supplied to the light source driving unit 62 and the rotation period determining unit 102.

  Next, in step S2, the rotation cycle determination unit 102 takes in the light emission timing signal supplied from the light emission timing generation unit 101, calculates the rotation cycle of the rotating fluorescent plate 13 that is asynchronous with the pulse cycle of this light emission timing signal, This rotation period value is supplied to the motor drive unit 63. For example, when the pulse period of the light emission timing signal is 1/120 second, the rotation period determination unit 102 applies 4.3, which is a non-integer, to 4.3 / 4.3 times 1/120 second. 120 seconds is obtained as the rotation period value and supplied to the motor drive unit 63. The non-integer value (referring to 4.3 in this example) may be determined in advance or may be set by an operator as appropriate.

  Next, in step S3, the motor drive unit 63 takes in the rotation cycle value supplied from the rotation cycle determination unit 102, generates a rotation instruction signal specifying the rotation cycle value, supplies the rotation instruction signal to the motor 14, and drives it. For example, the motor driving unit 63 takes in 4.3 / 120 which is the rotation period value supplied from the rotation period determining unit 102 and sets the rotation instruction signal for specifying the rotation period value, that is, the rotation axis of the motor 14 to 120. /4.3=Rotation instruction signal instructing to rotate at about 27.9 rotations / second is generated and supplied to the motor 14.

Next, the motor driving unit 63 takes in the position information of the rotating shaft supplied from the motor 14 and supplies the position information to the rotation period determining unit 102.
Next, the rotation cycle determination unit 102 takes in the position information of the rotating shaft supplied from the motor driving unit 63 and determines whether or not the motor 14 is rotating based on this position information. When it is determined that the motor 14 is not rotating, the rotation cycle determination unit 102 sets an abnormality flag indicating an abnormal state. Then, when the abnormality flag is set, the control unit 61 generates, for example, an alarm signal and outputs it to the outside.

  In step S4, the light source driving unit 62 takes in the light emission timing signal supplied from the light emission timing generation unit 101, and causes the solid-state light source 11 to emit light based on the light emission timing signal. For example, when the pulse period of the light emission timing signal is 1/120 seconds (the positive active period is 0.1 / 120 seconds, for example), the light source driving unit 62 uses the positive period (0.1 / 120 of the light emission timing signal). The solid light source 11 is caused to emit light during a period of seconds).

Next, in step S <b> 5, the control unit 61 supplies an image output request signal to the image signal supply unit 64.
Next, the image signal supply unit 64 takes in the image output request signal supplied from the control unit 61, and synchronizes the image signal supplied from the outside with the frame synchronization signal in accordance with the image output request signal. The power is supplied to the elements 30R, 30G, and 30B, respectively.

As described above, when the control system of the projector 1 operates, the projector 1 operates as follows.
When the motor 14 takes in the rotation instruction signal supplied from the motor drive unit 63 and rotates the rotation shaft at a rotation cycle corresponding to the rotation instruction signal, the rotating fluorescent screen 13 fixed to the rotation shaft rotates at the rotation cycle. To do. For example, when the motor 14 receives and receives a rotation instruction signal having a content for instructing the rotation axis to rotate at 120 / 4.3 (about 27.9) rotations / second from the motor driving unit 63, the motor 14 takes about 27. The rotating fluorescent plate 13 is rotated at a rotation period of 9 rotations / second.

  Next, the fixed light source 11 emits blue light, which is excitation light, by driving the light source driving unit 62. For example, the fixed light source 11 has a positive period of the light emission timing signal by driving the light source driving unit 62 based on the light emission timing signal whose pulse cycle is 1/120 seconds (the positive active period is 0.1 / 120 seconds, for example). Blue light is emitted during a period of 0.1 / 120 seconds. That is, the fixed light source 11 repeats the emission of blue light for 0.1 / 120 seconds at a cycle of 1/120 seconds.

  Since the emission period (for example, 1/120 second) of the blue light emitted from the solid light source 11 and the rotation period (for example, 4.3 / 120 second) of the rotating fluorescent plate 13 are asynchronous, the phosphor of the rotating fluorescent plate 13 The irradiation position of the blue light on 13b moves around with time.

Therefore, in the projector 1 according to the present embodiment, the irradiation position of the blue light on the phosphor 13b always moves, so that the temperature rise of the irradiation portion of the phosphor 13b can be suppressed, and the deterioration of the phosphor is extremely delayed. Therefore, high-quality fluorescence can be obtained. Moreover, since the projector 1 has the structure which shifts the irradiation position of the blue light to the fluorescent substance 13b using one motor 14, it can implement | achieve the illuminating device 10 small with a simple structure.
When the phosphor is mixed with the transparent resin and formed on the surface of the flat plate, it is possible to suppress the problem that the transparent resin is deteriorated, the light transmittance is reduced, and the fluorescence is darkened.

[Second Embodiment]
Next, a projector according to a second embodiment of the invention will be described. The overall configuration of the projector of this embodiment is the same as that of the projector 1 of the first embodiment shown in FIG. However, the projector according to the present embodiment is different from the projector 1 according to the first embodiment in the control system. Hereinafter, in the description of the configuration, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

FIG. 6 is a block diagram illustrating a functional configuration of a control system that controls the operation of the projector according to the present embodiment. In the figure, only the components necessary for explanation are extracted and simplified from the configurations shown in FIG.
In the same figure, the projector 1a which is this embodiment is equipped with the optical sensor 65 as a control system newly compared with the projector 1 which is 1st Embodiment, and the control part 61 and the light source drive part 62 in the projector 1 are provided. The control unit 61a and the light source driving unit 62a are changed.

  The optical sensor 65 is a light amount sensor, for example, and detects the amount of fluorescent light emitted from the phosphor 13b and supplies it to the control unit 61a. The optical sensor 65 is provided between the phosphor 13 b provided on the rotating fluorescent plate 13 and the liquid crystal display element 30 at a position where the light beam incident on the liquid crystal display element 30 is not blocked. However, the optical sensor 65 is provided as close as possible to the optical path. This is to detect light (this light is referred to as leakage light) that is not irradiated on the liquid crystal display element 30 out of the light flux directed from the phosphor 13b to the liquid crystal display element 30. The optical sensor 65 can detect the fluorescence emitted from the phosphor 13b by detecting this light leakage.

  Specifically, the optical sensor 65 is between the illumination device 10 that emits white light and any one of the liquid crystal display elements 30R, 30G, and 30B, and is incident on the liquid crystal display elements 30R, 30G, and 30B. It is provided at a position that does not block light. When the optical sensor 65 is provided in the vicinity of the optical path between the illumination device 10 and the dichroic mirror 21 provided in the color separation light guide optical system 20, the optical sensor 65 determines the amount of white light emitted from the illumination device 10. Can be detected.

  Further, when the optical sensor 65 is provided in the vicinity of the optical path between the dichroic mirror 21 and the liquid crystal display element 30R, the optical sensor 65 can detect the amount of red light. Further, when the optical sensor 65 is provided in the vicinity of the optical path between the dichroic mirror 22 and the liquid crystal display element 30G, the optical sensor 65 can detect the amount of green light. Further, when the optical sensor 65 is provided in the vicinity of the optical path between the dichroic mirror 22 and the liquid crystal display element 30B, the optical sensor 65 can detect the amount of blue light. When the optical sensor 65 is provided in the vicinity of the optical path between the dichroic mirrors 21 and 22, the optical sensor 65 can detect the light amounts of green light and blue light.

As in the first embodiment, the control unit 61a is realized including a CPU, a ROM, and a RAM (all of which are not shown). The CPU reads the control program stored in the ROM, expands it in the RAM, and executes the program steps on the RAM. By executing the program by the CPU, the control unit 61a controls the overall operation of the projector 1a.
As compared with the control unit 61 in the first embodiment, the control unit 61a further includes a light source output level adjustment unit 103 as a functional configuration.

  The light source output level adjustment unit 103 takes in the light emission timing signal supplied from the light emission timing generation unit 101, and obtains the rotation period value of the rotating fluorescent plate 13 and the position information of the rotation axis of the motor 14 supplied from the rotation period determination unit 102. The reference position signal including the reference value is captured, and the light amount value (light amount value) supplied from the optical sensor 65 is captured. Then, the light source output level adjustment unit 103 identifies a part having a low light amount in the phosphor 13b as a fluorescent deterioration part based on the acquired rotation period value and the reference position and light quantity value in the position information. Further, the light source output level adjustment unit 103 generates a light emission level correction signal for the part based on the position of the part where the light amount is low, the light amount value thereof, and the light emission timing signal, and uses the light emission level correction signal as the light source drive part 62a. To supply. Details of the operation of the light source output level adjustment unit 103 will be described later.

  The light source driving unit 62a takes in the light emission timing signal supplied from the light emission timing generation unit 101 and the light emission level correction signal supplied from the light source output level adjustment unit 103, and based on the timing indicated by the light emission timing signal, the light emission level. The solid light source 11 is caused to emit light intermittently with the output value corrected with the light emission level correction value indicated by the correction signal. That is, when the light emission timing signal is a positive active pulse signal, the light source driving unit 62 causes the solid-state light source 11 to emit light during the positive period of the light emission timing signal. In the present embodiment, the level value of the excitation light emitted from the light source driving unit 62a is a value corrected with the light emission level correction value.

Next, control of the projector 1a executed by the control system having the above-described configuration will be described with reference to FIGS.
FIG. 7 is a flowchart showing a procedure of processing executed by the control system of the projector 1a according to the present embodiment. When the control unit 61a activates the control program and the synchronization signal generation unit of the image signal supply unit 64 starts generating the frame synchronization signal, the processing according to the flowchart of FIG.
In addition, since the process from step S21 to step S23 is the same as the process from step S1 to step S3 in 1st Embodiment, description about the process from step S21 to step S23 is abbreviate | omitted.

Following step S23, in step S24, the light source output level adjustment unit 103 supplies a light emission level correction signal with a light emission level correction value of 0 (zero; not corrected) to the light source drive unit 62a.
Next, the light source driving unit 62 a takes in the light emission timing signal supplied from the light emission timing generation unit 101 and takes in the light emission level correction signal supplied from the light source output level adjustment unit 103.
Next, the light source driving unit 62a causes the solid-state light source 11 to emit light with an output value corrected with the light emission level correction value indicated by the light emission level correction signal based on the timing indicated by the light emission timing signal. However, since the light emission level correction value is 0 (zero) here, the output value is not corrected. For example, when the pulse period of the light emission timing signal is 1/120 seconds (the positive active period is 0.1 / 120 seconds, for example), the light source driving unit 62 uses the positive period (0.1 / 120 of the light emission timing signal). In the second period), the solid-state light source 11 is caused to emit light without correcting the output value.

Next, in step S <b> 25, the control unit 61 a supplies an image output request signal to the image signal supply unit 64.
Next, the image signal supply unit 64 takes in the image output request signal supplied from the control unit 61a, and synchronizes the image signal supplied from the outside with the frame synchronization signal in accordance with the image output request signal. The power is supplied to the elements 30R, 30G, and 30B.

  Next, in step S <b> 26, the light source output level adjustment unit 103 monitors the rotation phase of the motor 14 and the amount of light detected by the optical sensor 65. Specifically, the light source output level adjustment unit 103 takes in the light emission timing signal supplied from the light emission timing generation unit 101, and the rotation period value of the rotating fluorescent plate 13 and the rotation of the motor 14 supplied from the rotation period determination unit 102. A reference position signal including axis position information is captured, and a light amount value supplied from the optical sensor 65 is captured.

  Next, in step S27, the light source output level adjusting unit 103 checks the captured light amount value. For example, the light source output level adjustment unit 103 determines whether the light amount value is equal to or less than a predetermined threshold value. When the light source output level adjustment unit 103 determines that the light amount value is equal to or smaller than the threshold value, the process proceeds to step S28, and when it is determined that the light amount value exceeds the threshold value, the process returns to step S26. Specifically, for example, in the timing chart shown in FIG. 8, when the light source output level adjustment unit 103 determines that the light amount value 201 is equal to or less than the threshold value, the process proceeds to step S <b> 28.

In step S <b> 28, the light source output level adjusting unit 103 captures the light amount value (a value equal to or less than the threshold value), the time corresponding to the reference position in the position information, and the rotation period value of the rotating fluorescent plate 13. Based on the above, a portion where the amount of light in the phosphor 13b is low is specified as a fluorescent deterioration portion. Specifically, for example, in the timing chart shown in FIG. 8, the light source output level adjustment unit 103 is a time difference between the time when the light amount value 201 is captured and the time corresponding to the reference position in the latest reference position signal. A certain time t _e is calculated. Next, the light source output level adjustment unit 103 calculates the revolving distance that the rotating fluorescent plate 13 travels from the reference position over the time t _e based on the time t _e and the rotation period value T _M of the rotating fluorescent plate 13. The arrival point is acquired as the position of the part S where the light amount value is equal to or less than the threshold value in the phosphor 13b.

  Next, in step S <b> 29, the light source output level adjustment unit 103 calculates a light emission level correction value for correcting a light amount value that is a value equal to or smaller than a threshold value. Specifically, for example, the light source output level adjustment unit 103 calculates an average value of a predetermined number of light amount values in the vicinity of the light amount value that is a value equal to or smaller than the threshold value, and calculates the average value and the light amount value equal to or smaller than the threshold value. The difference is calculated, and the difference value is determined as the light emission level correction value.

  Next, in step S30, the light source output level adjusting unit 103 determines the time corresponding to the low light quantity part and the time indicating the irradiation period in the light emission timing signal based on the position of the low light quantity part and the light emission timing signal. A light emission level correction signal representing the matching timing and the light emission level correction value is generated and supplied to the light source driving unit 62a. Specifically, for example, in the timing chart shown in FIG. 9, the light source output level adjusting unit 103 matches the timing corresponding to the portion S where the light amount is low and the time indicating the irradiation period in the light emission timing signal (reference numeral 202). ) And a light emission level correction signal representing the light emission level correction value are generated and supplied to the light source driving unit 62a. In the figure, reference numeral 203 indicates the light quantity value of the blue light whose output level is corrected.

  After the process of step S30, the process returns to step S26.

As described above, when the control system of the projector 1a operates, the projector 1a operates as follows.
When the motor 14 takes in the rotation instruction signal supplied from the motor drive unit 63 and rotates the rotation shaft at a rotation cycle corresponding to the rotation instruction signal, the rotating fluorescent screen 13 fixed to the rotation shaft rotates at the rotation cycle. To do. For example, when the motor 14 receives and receives a rotation instruction signal having a content for instructing the rotation axis to rotate at 120 / 4.3 (about 27.9) rotations / second from the motor driving unit 63, the motor 14 takes about 27. The rotating fluorescent plate 13 is rotated at a rotation period of 9 rotations / second.

  Next, the fixed light source 11 emits blue light, which is excitation light, by driving the light source driving unit 62a. For example, the fixed light source 11 has a positive period of the light emission timing signal by driving the light source driving unit 62a based on the light emission timing signal whose pulse cycle is 1/120 second (the positive active period is 0.1 / 120 second, for example). Blue light is emitted during a period of 0.1 / 120 seconds. That is, the fixed light source 11 repeats the emission of blue light for 0.1 / 120 seconds at a cycle of 1/120 seconds.

  Since the emission period (for example, 1/120 second) of the blue light emitted from the solid light source 11 and the rotation period (for example, 4.3 / 120 second) of the rotating fluorescent plate 13 are asynchronous, the phosphor of the rotating fluorescent plate 13 The irradiation position of the blue light on 13b moves around with time.

The phosphor 13b continuously formed along the circumferential direction on one surface of the circular plate 13a of the rotating fluorescent plate 13 may cause variations in the amount of light emitted depending on the variation of components and the application state. Therefore, even in the initial state, the light emission amount may vary depending on the portion of the phosphor 13b.
Further, the degree of progress of deterioration may vary depending on the portion of the phosphor 13b. Therefore, the variation in the amount of light emitted from the phosphor 13b may increase with time.
The projector 1a which is this embodiment detects the site | part where the light quantity value fell by making predetermined light quantity value into a threshold value when the dispersion | variation in the emitted light quantity from the fluorescent substance 13b like these occurs, and the solid light source 11 When irradiating the part, the light source driving unit 62a is controlled so as to increase the output level.

Therefore, in the projector 1a which is this embodiment, since the irradiation position of the blue light in the fluorescent substance 13b always moves, the temperature rise of the irradiation part of the fluorescent substance 13b can be suppressed, and the deterioration of the fluorescent substance is extremely delayed. Can do. Moreover, since the projector 1a has the structure which shifts the irradiation position of the blue light to the fluorescent substance 13b using one motor 14, the illuminating device 10 can be realized in a small size with a simple structure. Furthermore, the projector 1a can emit higher-quality fluorescence by suppressing variations in the amount of light emitted from the phosphor 13b.
When the phosphor is mixed with the transparent resin and formed on the surface of the flat plate, it is possible to suppress the problem that the transparent resin is deteriorated, the light transmittance is reduced, and the fluorescence is darkened.

In the first and second embodiments described above, the phosphor 13b is formed on one surface of the light-transmitting substrate (disk 13a), and excitation light is incident from the disk 13a side. Although it is configured to irradiate the phosphor 13b, it is also possible to adopt a configuration in which the phosphor 13b is irradiated by making excitation light incident from the phosphor 13b side, and the generated fluorescence is reflected by the disk 13a to extract the fluorescence. it can. In this case, the substrate (disk 13a) may not have light transmittance.
In the first and second embodiments described above, the projectors 1 and 1a to which the transmissive liquid crystal display elements 30R, 30G, and 30B are applied are shown. In addition to this, for example, three reflective liquid crystal display elements may be used, and the color separation light guide optical system may be configured so as to be compatible with these reflective liquid crystal display elements.

  As mentioned above, although embodiment of this invention was explained in full detail with reference to drawings, the specific structure is not restricted to those embodiment, The design etc. of the range which does not deviate from the summary of this invention are included.

  DESCRIPTION OF SYMBOLS 1,1a Projector 10 Illuminating device 11 Solid light source 13 Rotating fluorescent plate 13a Disc 13b Phosphor 13c Dichroic film 14 Motor 15 Collimator optical system 20 Color separation light guide optical system 30R, 30G, 30B Liquid crystal display element 40 Cross dichroic prism 50 Projection Optical system 61, 61a Control unit 62, 62a Light source drive unit 63 Motor drive unit 64 Image signal supply unit 65 Optical sensor 101 Light emission timing generation unit 102 Rotation period determination unit 103 Light source output level adjustment unit SCR screen.

[1] In order to solve the above-described problem, an illumination device according to one embodiment of the present invention is continuously provided along a circumferential direction of a solid light source that emits excitation light, a flat plate, and a circle on the flat plate. And a phosphor that converts the excitation light into fluorescence, a motor that rotates the phosphor around an axis that passes through the center of the circle, and light emission that generates a light emission timing signal having a predetermined period A timing generation unit, a rotation period determination unit that determines a rotation period that is a non-integer multiple of the predetermined period, and that determines whether or not the motor unit is rotating; and driving the motor unit to drive the fluorescent plate A motor drive unit that matches the rotation period of the solid light source intermittently with the predetermined cycle, and a light source drive unit that intermittently emits light at the predetermined cycle. In the first aspect of the present invention, the irradiation position of the excitation light in the phosphor always moves, so that the temperature rise of the phosphor irradiation portion can be suppressed, and the deterioration of the phosphor can be extremely slowed. High-quality fluorescence can be obtained. In addition, the first aspect of the present invention has a configuration in which the irradiation position of the excitation light to the phosphor is shifted using a single motor unit, and thus can be realized in a small size with a simple structure.
[2] The illumination device according to [1], wherein the rotation period determination unit determines a rotation period that is a non-integer times a period of the light emission timing signal.
With this configuration, even in the second aspect of the present invention, the irradiation position of the excitation light in the phosphor always moves, so that the temperature rise of the phosphor irradiation portion can be suppressed, and the phosphor is deteriorated. It can be made very slow, so that high quality fluorescence can be obtained.
[3] In the illumination device according to [1] or [2], the light source driving unit has an output level adjustment function of the solid-state light source, and includes a light detection unit that detects the fluorescence, and a light detection unit. A light source output level adjusting unit that controls the output level adjusting function of the light source driving unit according to a detection result, and the light source driving unit is configured to control the output level adjusting function from the solid-state light source. The output level of the excitation light is corrected.
With this configuration, in the third aspect of the present invention, it is possible to obtain higher-quality fluorescence while suppressing variations in the amount of light emitted from the phosphor.
[4] The illumination device according to any one of [1] to [3], wherein the solid-state light source emits blue light, and the phosphor emits part of the blue light as red light. While converting into green light, another part of the blue light is transmitted.

[5] In order to solve the above-described problem, a projector according to one embodiment of the present invention is provided continuously along a circumferential direction of a solid light source that emits excitation light, a flat plate, and a circle on the flat plate. A phosphor that converts the excitation light into fluorescence; a motor that rotates the phosphor around an axis that passes through the center of the circle; and a predetermined period synchronized with the frame period of the image signal. A light emission timing generation unit that generates a light emission timing signal, a rotation cycle determination unit that determines a rotation cycle that is a non-integer multiple of the predetermined cycle, and that determines whether the motor unit is rotating; and A motor driving unit that drives the motor unit to match the rotation cycle of the fluorescent plate with the rotation cycle; a light source driving unit that intermittently emits the solid-state light source at the predetermined cycle; A light modulation unit that modulates the signal to generate image light, characterized in that it comprises a projection optical system that projects the image light.
With this configuration, in the fifth aspect of the present invention, since the irradiation position of the excitation light in the phosphor constantly moves, it is possible to suppress the temperature rise of the irradiated portion of the phosphor, and to deteriorate the phosphor. It can be made very slow, so that high quality fluorescence can be obtained. Further, in the fifth aspect of the present invention, since the irradiation position of the excitation light to the phosphor is shifted using a single motor unit, it can be realized with a simple structure and a small size.
[6] The projector according to [5], wherein the rotation period determination unit determines a rotation period that is a non-integer times one of the period of the light emission timing signal.
With this configuration, even in the sixth aspect of the present invention, the irradiation position of the excitation light in the phosphor always moves, so that the temperature rise of the phosphor irradiation portion can be suppressed, and the phosphor is deteriorated. It can be made very slow, so that high quality fluorescence can be obtained.
[7] In the projector according to [5] or [6], the light source driving unit has an output level adjustment function of the solid-state light source, and a light detection unit that detects the fluorescence, and detection of the light detection unit A light source output level adjusting unit that controls the output level adjusting function of the light source driving unit according to a result, wherein the light source driving unit performs the excitation from the solid light source according to the control of the output level adjusting function The light output level is corrected.
With this configuration, in the seventh aspect of the present invention, it is possible to emit higher-quality fluorescence while suppressing variations in the amount of light emitted from the phosphor.
[8] In the projector according to any one of [5] to [7], the solid-state light source emits blue light, and the phosphor converts part of the blue light into red light and green light. The light is converted into light, and another part of the blue light is transmitted.

Claims (8)

A solid-state light source that emits excitation light;
A phosphor that converts the excitation light into fluorescence;
A fluorescent plate on which the phosphor is continuously formed along the circumferential direction of a circle on a flat plate;
A motor unit for rotating the fluorescent plate around an axis passing through the center of the circle;
A light emission timing generator for generating a light emission timing signal having a period synchronized with the frame period;
A rotation period determining unit that determines a rotation period that is a non-integer multiple of the period of the light emission timing signal;
A motor drive unit that drives the motor unit to match the rotation period of the fluorescent screen with the rotation period;
A light source driving unit that causes the solid-state light source to emit light intermittently at a cycle of the light emission timing signal;
A lighting device comprising: The lighting device according to claim 1, wherein the rotation cycle determination unit determines a rotation cycle that is a non-integer times the cycle of the light emission timing signal. The light source driving unit has an output level adjustment function of the solid light source,
A light detection unit for detecting the fluorescence;
A light source output level adjustment unit that controls the output level adjustment function of the light source drive unit according to the detection result of the light detection unit;
Further comprising
The lighting device according to claim 1, wherein the light source driving unit corrects the output level of the excitation light from the solid-state light source according to control of the output level adjustment function. The solid-state light source emits blue light;
4. The phosphor according to claim 1, wherein the phosphor converts part of the blue light into red light and green light and transmits the other part of the blue light. 5. The lighting device according to item. A solid-state light source that emits excitation light;
A phosphor that converts the excitation light into fluorescence;
A light modulator that modulates the fluorescence with an image signal to generate image light;
A projection optical system for projecting the image light;
A fluorescent plate on which the phosphor is continuously formed along the circumferential direction of a circle on a flat plate;
A motor unit for rotating the fluorescent plate around an axis passing through the center of the circle;
A light emission timing generation unit that generates a light emission timing signal having a period synchronized with a frame period of the image signal;
A rotation period determining unit that determines a rotation period that is a non-integer multiple of the period of the light emission timing signal;
A motor drive unit that drives the motor unit to match the rotation period of the fluorescent screen with the rotation period;
A light source driving unit that causes the solid-state light source to emit light intermittently at a cycle of the light emission timing signal;
A projector comprising: The projector according to claim 5, wherein the rotation period determination unit determines a rotation period that is a non-integer times a period of the light emission timing signal. The light source driving unit has an output level adjustment function of the solid light source,
A light detection unit for detecting the fluorescence;
A light source output level adjustment unit that controls the output level adjustment function of the light source drive unit according to the detection result of the light detection unit;
Further comprising
The projector according to claim 5, wherein the light source driving unit corrects the output level of the excitation light from the solid-state light source according to control of the output level adjustment function. The solid-state light source emits blue light;
8. The phosphor according to claim 5, wherein the phosphor converts a part of the blue light into red light and green light and transmits the other part of the blue light. The projector according to item.

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