JP6179130B2 - Light source device and projection device - Google Patents

Description

  The present invention relates to a light source device and a projection device.

  Patent Document 1 discloses a time division light source device that emits light of a plurality of colors in a time division manner. In the fluorescent wheel of this light source device, a phosphor layer is provided along the circumferential direction at a central angle of 180 °, and a diffuse transmission layer is provided along the circumferential direction at a central angle of 180 ° (FIG. 1). 6). The fluorescent wheel is rotated by a motor, the optical axis of the excitation light source that emits excitation light intersects the fluorescent wheel, and there is also a red light source. The excitation light source and the red light source blink at high speed, the blinking period of the excitation light source and the red light source is equal to the rotation period of the motor, and the blinking of the excitation light source and the blinking of the red light source are in opposite phases (see FIG. )reference). While the excitation light source is turned on, the red light source is turned off, and during that period, a part of the diffuse transmission layer and a part of the phosphor layer pass through the optical axis of the excitation light. If the diffuse transmission layer passes the optical axis of the excitation light during the lighting period of the excitation light source, the blue excitation light that has passed through the diffusion transmission layer is emitted from the light source device, and the phosphor layer during the lighting period of the excitation light source Passes through the optical axis of the excitation light, the green light emitted from the phosphor layer is emitted from the light source device. While the excitation light source is turned off, the red light source is turned on, and the red light emitted from the red light source is emitted from the light source device.

JP 2011-170363 A

  In the technique described in Patent Document 1, the region irradiated with excitation light is a part of the phosphor layer. Since the motor and the excitation light source operate periodically, the region irradiated with the excitation light is limited to only a part of the phosphor layer. For this reason, the life of the phosphor layer may be shortened. In addition, a luminance saturation phenomenon may occur in the phosphor layer. Luminance saturation refers to a phenomenon in which when the energy density of irradiated excitation light exceeds a certain value, the fluorescence intensity does not increase as the energy density increases.

  Therefore, the problem to be solved by the present invention is to extend the lifetime of the fluorescent region such as the phosphor layer provided on the rotating optical plate and to suppress the occurrence of luminance saturation in the fluorescent region. is there.

In order to solve the above-described problems, a light source device according to the present invention includes an excitation light generator that emits excitation light, a fluorescent region that intersects the optical axis of the excitation light, and passes in the circumferential direction through the intersection. An optical plate provided with a light diffusing and transmitting region; a rotation driver that rotates the optical plate in a circumferential direction; and a light source control unit that controls the excitation light generation device and the rotation driver. parts are during one frame period in which one frame image is generated, the rotational drive unit to control, the optical plate is rotated by the number of times of the two or more integral multiple, the light source control unit, said During the period from when the fluorescent region starts to pass through the optical axis of the excitation light to when it finishes passing, the excitation light generator is turned on at least once during the one frame period, and the fluorescent region is the excitation light. Until it has passed through It performs one or more times in the one frame period that turns off the excitation light generator during the said light source control section, during the period in which the light-diffusing transmissive region passes through the optical axis of the excitation light The excitation light generator is turned on for the number of times that is an integer multiple during the one frame period .

  According to the present invention, the lifetime of the fluorescent region of the optical plate can be extended. In addition, it is possible to suppress the occurrence of luminance saturation in the fluorescent region.

It is a top view of the projector concerning an embodiment of the present invention. It is a block diagram of the projection device concerning the embodiment. It is a top view of the optical plate concerning the embodiment. It is a timing chart for demonstrating the period and operation | movement timing of a display element, a light source, an excitation light generator, and a spindle motor. It is a timing chart for demonstrating the period and operation | movement timing of a display element, a light source, an excitation light generator, and a spindle motor. It is a timing chart for demonstrating the period and operation | movement timing of a display element, a light source, an excitation light generator, and a spindle motor.

  EMBODIMENT OF THE INVENTION Below, the form for implementing this invention is demonstrated using drawing. However, the embodiments described below are given various technically preferable limitations for carrying out the present invention, but the scope of the present invention is not limited to the following embodiments and illustrated examples.

FIG. 1 is a plan view of the projection apparatus 100. FIG. 2 is a block diagram of the projection apparatus 100.
The projection apparatus 100 includes a light source device (time-division light generation device, sequential color generation device) 1, a light source side optical system 2, a display element 3, a projection optical system 4, and the like (see FIG. 1). Furthermore, the projection apparatus 100 includes a video signal processing unit 91, a display controller 92, a VRAM 93, and a system controller 94 (see FIG. 2).

  The video signal processing unit 91 is provided with a video input terminal. The video signal output by the external device is input to the video signal processing unit 91 through the video cable and the video input terminal. The video signal processing unit 91 performs various signal processes on the video signal input from the external device. For example, the video signal processing unit 91 performs scaling of a video signal input from an external device to increase or decrease the resolution of the video signal, change the aspect ratio of the video signal, or perform digital keystone correction on the video signal. Or do.

  The display controller 92 drives the display element 3 based on the video signal signal-processed by the video signal processing unit 91. Further, the display controller 92 controls the light source device 1 (particularly, the light source control unit 70 of the light source device 1) based on the video signal signal-processed by the video signal processing unit 91.

  The VRAM 93 temporarily stores the video signal, and the video signal processing unit 91 temporarily records and reads the video signal during signal processing. Further, the display controller 92 reads the video signal temporarily recorded in the VRAM 93.

  The system controller 94 integrally controls the display controller 92 and the light source device 1 (particularly, the light source control unit 70).

  The light source device 1 divides the emitted light into light of a plurality of different colors by time and emits the light of the plurality of colors. Specifically, the light source device 1 repeatedly emits red light, green light, and blue light in a predetermined order. The light source device 1 emits red light, green light, and blue light at least once per cycle. One period is a period in which a color image of one frame is generated by the display element 3. In the present embodiment, a color image will be described below as an example. However, the present invention is not limited to this, and it is needless to say that the present invention can be applied to a case where a monochrome image is displayed, for example.

  The light source side optical system 2 projects red light, green light, and blue light emitted from the light source device 1 onto the display element 3. The light source side optical system 2 includes a light guide device (integrator) 2a, a lens 2b, an optical axis conversion mirror 2c, a lens group 2d, an irradiation mirror 2e, and a field lens 2f (see FIG. 1). Of these, the field lens 2 f is used as both the light source side optical system 2 and the projection optical system 4.

  The light guide device 2a is a light tunnel or a light rod. The light guide device 2a reflects the red light, the green light, and the blue light emitted from the light source device 1 on the side surface a plurality of times or totally, thereby converting the red light, the green light, and the blue light into a light flux having a uniform intensity distribution. To do. The lens 2b projects and collects red light, green light, and blue light guided by the light guide device 2a toward the optical axis conversion mirror 2c. The optical axis conversion mirror 2c reflects red light, green light, and blue light projected by the lens 2b toward the lens group 2d. The lens group 2d projects and collects red light, green light, and blue light reflected by the optical axis conversion mirror 2c toward the irradiation mirror 2e. The irradiation mirror 2e reflects the light projected by the lens group 2d toward the display element 3. The field lens 2 f projects the light reflected by the irradiation mirror 2 e onto the display element 3.

  The display element 3 is a spatial light modulator, and an image is generated by modulating red light, green light, and blue light irradiated by the light source side optical system 2 with each pixel. The display element 3 generates one frame of color video per cycle, and the one frame of color video is divided into red video, green video, and blue video by time. That is, the display element 3 generates a red video, a green video, and a blue video at least once per cycle, and a frame obtained by combining the red video, the green video, and the blue video formed in one cycle with time. Corresponds to a color image.

The period of the display element 3 and the period of the light source device 1 are equal. The cycle of the display element 3 corresponds to a cycle in which one frame of color video is generated. That is, the period of the display element 3 corresponds to a period in which the display element 3 generates the red video, the green video, and the blue video at least once.
The display element 3 generates a red image in synchronization with a period in which red light is emitted by the light source device 1. The display element 3 generates a green image in synchronization with a period in which green light is emitted by the light source device 1. The display element 3 generates a blue image in synchronization with a period in which blue light is emitted by the light source device 1. The cycle and display operation of the display element 3 are controlled by the display controller 92. The display controller 92 outputs the phase in the cycle of the display element 3 to the light source control unit 70.

  The display element 3 is a digital micromirror device (DMD) having a plurality of movable micromirrors arranged in a two-dimensional array. The display element 3 is driven by the display controller 92. That is, when the red light is irradiated on the display element 3, the time during which the red light is reflected toward the projection optical system 4 by controlling (for example, PWM control) each movable micromirror of the display element 3. The ratio (duty ratio) is controlled for each movable micromirror. Thereby, a red image is generated by the display element 3. The same applies when the display element 3 is irradiated with green light or blue light.

  The display element 3 may be a transmissive spatial light modulator (for example, a liquid crystal shutter array panel: a so-called liquid crystal display) instead of a reflective spatial light modulator. When the display element 3 is a transmissive spatial light modulator, the optical design of the light source side optical system 2 is changed, and the optical axes of red light, green light, and blue light irradiated by the light source side optical system 2 are described later. The display element 3 is disposed between the projection optical system 4 and the light source side optical system 2 so as to overlap the optical axis of the projection optical system 4.

  The projection optical system 4 is a lens array composed of a plurality of lenses. The projection optical system 4 is provided so as to face the display element 3, and the optical axis of the projection optical system 4 extends back and forth and intersects the display element 3. The projection optical system 4 projects the image generated by the display element 3 onto the screen by projecting the light reflected by the display element 3 forward. The projection optical system 4 includes a movable lens group 4a and a fixed lens group 4b. The projection optical system 4 is capable of changing the focal length and focusing by moving the movable lens group 4a.

  Hereinafter, the light source device 1 will be specifically described. The light source device 1 includes an excitation light generation device 10, a reduction optical system 20, a light source 31, an excitation light conversion device 32, an optical path synthesis optical system 40, a condensing optical system 50, and the like (see FIG. 1). The light source device 1 further includes a light source control unit 70, a motor driver 71, and a phase sensor 72 (see FIG. 2).

-About the excitation light generator 10 The excitation light generator 10 emits the excitation light (excitation beam) which is parallel light. The excitation light emitted by the excitation light generator 10 is a bundle of a plurality of excitation rays that travel in parallel with each other. The excitation light generator 10 includes a plurality of excitation light sources 11, a plurality of collimator-lenses 12, and a plurality of reflection mirrors 13. The excitation light emitted by the excitation light generator 10 excites a phosphor layer 34e described later.

  The excitation light source 11 is a semiconductor light emitting element that emits excitation light, and more specifically is a blue laser diode. These excitation light sources 11 are arranged in a two-dimensional array (lattice) along a plane perpendicular to the paper surface of FIG. A plurality of collimator lenses 12 are arranged in a two-dimensional array (lattice) along a plane perpendicular to the paper surface of FIG. The collimator-lens 12 faces the excitation light source 11 respectively. The optical axis of the excitation light beam collimated by the collimator-lens 12 relative to the excitation light source 11 and the collimator lens 12 so that the reflection mirror 13 is inclined with respect to the optical axis of the excitation light beam emitted from the excitation light source 11. Is converted by 90 ° by the reflecting mirror 13. These reflecting mirrors 13 are arranged in a staircase pattern. The interval between the optical axes of the excitation light beams collimated by the collimator-lens 12 is narrowed by these reflection mirrors 13, and the light diameter of the entire bundle of excitation light beams reflected by these reflection mirrors 13 is reflected by the reflection mirror 13. It becomes thinner than the light diameter of the entire bundle of previous laser beams. The excitation light beams reflected by these reflecting mirrors 13 travel substantially in parallel, these excitation light beam bundles are parallel light, and these excitation light beam bundles are excitation light (blue light) emitted by the excitation light generator 10. is there.

  The excitation light generator 10 and the excitation light source 11 blink. The blinking of the excitation light generator 10 and the excitation light source 11 is so fast that it cannot be identified with the naked eye. The blinking cycle of the excitation light generator 10 and the excitation light source 11 is equal to or greater than the cycle of the display element 3, and the excitation light generator 10 and the excitation light source 11 are in a period during which a color image of one frame is generated by the display element 3. Flashes once or more.

  Note that the number of pairs of the excitation light source 11 and the collimator-lens 12 is one set, and the reflection mirror 13 may not be provided. In that case, the optical axes of the collimator-lens 12 and the excitation light source 11 are orthogonal to the optical plate 34 at a position shifted from the center of the optical plate 34. In that case, the reduction optical system 20 may be omitted.

-About the reduction optical system 20 The reduction optical system 20 is a lens group including lenses 21 and 22. The reduction optical system 20 is arranged on the side where the excitation light beam is reflected by the reflection mirror 13. Further, the reduction optical system 20 is arranged so that the optical axis of the reduction optical system 20 coincides with the optical axis of the bundle of excitation light beams reflected by the reflection mirror 13. The reduction optical system 20 reduces the diameter of the excitation light emitted by the excitation light generator 10. That is, the reduction optical system 20 condenses the bundle of excitation light beams reflected by the plurality of reflection mirrors 13 and narrows the interval between these laser beams.

About the excitation light conversion device 32

  The excitation light conversion device 32 converts the excitation light into fluorescence (green light) and diffuse transmission light (blue light). That is, the excitation light conversion device 32 generates fluorescence from the excitation light emitted by the excitation light generation device 10 and generates diffuse transmitted light by transmitting the excitation light so as to diffuse. The fluorescence generated by the excitation light conversion device 32 travels in the direction opposite to the traveling direction of the excitation light. The diffuse transmitted light generated by the excitation light conversion device 32 travels in the same direction as the traveling direction of the excitation light.

The excitation light conversion device 32 includes a spindle motor (rotary drive) 33 and an optical plate 34.
The spindle motor 33 rotates the optical plate 34 in the circumferential direction. The spindle motor 33 rotates at a constant speed, and the rotation cycle of the spindle motor 33 is constant. The rotation cycle of the spindle motor 33 is an integer of 2 or more (preferably an even number) of the cycle of the display element 3, and is preferably an integer of 2 or more (an even number) of the rotation cycle of the spindle motor 33. ) Times is the period of the display element 3. That is, the spindle motor 33 rotates the optical plate 34 twice or more during a period in which a color image of one frame is generated by the display element 3.

  The optical plate 34 is provided in a disc shape, and the center of the optical plate 34 is connected to the drive shaft of the spindle motor 33. The optical plate 34 is orthogonal to the optical axis of the excitation light emitted by the excitation light generator 10 at a position shifted from the drive axis of the spindle motor 33.

  FIG. 3 is a plan view of the optical plate 34. The direction of viewing FIG. 3 and the direction of viewing FIG. 1 are perpendicular. As shown in FIG. 3, the optical plate 34 is divided into two segments 34a and 34b along the circumferential direction. The first segment 34a is a fluorescent region and the second segment 34b is a light diffusing and transmitting region. The first segment 34a and the second segment 34b are provided on the same circumference. The ratio of the central angles of the first segment 34a and the second segment 34b is, for example, “2: 1” or “1: 1”. However, the division ratio between the first segment 34a and the second segment 34b is not particularly limited. Hereinafter, the optical plate 34, the first segment 34a, and the second segment 34b will be described in detail.

The optical plate 34 includes a wheel plate 34d, a phosphor layer 34e, a diffuse transmission plate 34f, and the like. The skeletal shape of the wheel plate 34d when grasping the shape of the wheel plate 34d roughly is a disc. The drive shaft of the spindle motor 33 is directly connected to the center of the wheel plate 34d. Therefore, the rotation cycle of the spindle motor 33 and the rotation cycle of the optical plate 34 are equal, and the rotation speed of the spindle motor 33 (the number of rotations per unit time) and the rotation speed of the optical plate 34 (the number of rotations per unit time) are equal. Therefore, the rotation period of the optical plate 34 is an integer (preferably an even number) of 2 or more of the period of the display element 3.
The drive axis of the spindle motor 33 is parallel to the optical axis of the reduction optical system 20, and the wheel plate 34 d is orthogonal to the optical axis of the reduction optical system 20.

  An opening 34g is formed in the wheel plate 34d, and the opening 34g extends in the circumferential direction. The circumferential direction refers to the circumferential direction around the drive shaft of the spindle motor 33, and the axial direction refers to the direction in which the drive shaft of the spindle motor 33 extends.

  A phosphor layer 34e is formed on the front surface of the wheel plate 34d. The joining interface between the phosphor layer 34e and the wheel plate 34d is mirror-finished, and the utilization efficiency of the fluorescence emitted from the phosphor layer 34e is improved. The front surface of the mirror-finished wheel plate 34 d faces the reduction optical system 20.

  When viewed in the axial direction, the phosphor layer 34e is formed in a circular arc shape so as to extend in the circumferential direction. The phosphor layer 34e and the opening 34g are juxtaposed in the circumferential direction, and the phosphor layer 34e and the opening 34g are on the same rotation trajectory. That is, when viewed in the axial direction, the phosphor layer 34 e and the opening 34 g are disposed on the same circumference with the drive shaft of the spindle motor 33 as the center. The portion where the phosphor layer 34e is formed corresponds to the first segment 34a.

  The phosphor layer 34e is not formed in the shape of a circular arc band, but the phosphor layer 34e may be formed on the entire front surface of the wheel plate 34d, or the phosphor layer 34e may drive the spindle motor 33. You may form in the fan shape centering on an axis | shaft.

  A disc-shaped diffuse transmission plate 34f is attached to the rear surface of the wheel plate 34d, and the opening 34g is closed by the diffusion transmission plate 34f. The part which obstruct | occluded the opening 34g among the diffuse transmission board 34f is equivalent to the 2nd segment 34b.

  If the phosphor layer 34e passes through the optical axis of the excitation light when the excitation light generating device 10 is turned on, fluorescence (green light) is emitted from the phosphor layer 34e. When the diffuse transmission plate 34f passes through the optical axis of the excitation light while the excitation light generator 10 is turned on, the excitation light passes through the diffusion transmission plate 34f, and the excitation light is diffused during the transmission.

・ About light source 31

The light source 31 emits light of a color different from the fluorescence (green light) and diffused transmission light (blue light) generated by the excitation light conversion device 32. That is, the light source 31 emits light having a wavelength band different from that of fluorescence and diffuse transmitted light. Specifically, the light source 31 emits red light.
The light source 31 is a semiconductor light emitting element, more specifically, a red light emitting diode. In the present embodiment, the light source 31 is a light emitting diode, but is not limited to a light emitting diode.
The optical axis of red light emitted by the light source 31 is parallel to the optical axis of excitation light emitted by the excitation light source 11. The optical axis of red light emitted by the light source 31 is orthogonal to the optical axis of excitation light emitted by the excitation light generator 10.

  The light source 31 blinks. The blinking of the light source 31 is so fast that it cannot be identified with the naked eye. The blinking cycle of the light source 31 is equal to or longer than the cycle of the display element 3, and the light source 31 blinks at least once during a period in which a color image of one frame is generated by the display element 3.

・ About optical path synthesis optical system 40

  The optical path synthesis optical system 40 uses red light emitted by the light source 31, fluorescence (green light) generated by the excitation light conversion device 32, and diffused transmission light (blue light) emitted by the excitation light conversion device 32 in the same optical path. Synthesize.

  The optical path synthesis optical system 40 includes a first optical path synthesis member 41, a second optical path synthesis member 42, a first reflection mirror 43, and a second reflection mirror 44.

  The first optical path synthesis member 41 synthesizes the red light emitted from the light source 31 and the fluorescence generated by the excitation light conversion device 32 into the same optical path. The first optical path combining member 41 is disposed at the intersection of the optical axis of red light emitted by the light source 31 and the optical axis of excitation light emitted by the excitation light generator 10. The first optical path combining member 41 obliquely intersects with the optical axis of red light emitted by the light source 31 at 45 °, and at 45 ° with respect to the optical axis of excitation light emitted by the excitation light generator 10. Oblique.

  The first optical path combining member 41 is a dichroic mirror. The first optical path combining member 41 reflects light in a predetermined band (green light) and transmits light outside the predetermined band (red light, blue light). Specifically, the first optical path synthesis member 41 transmits the excitation light (blue light) emitted by the excitation light generation device 10 toward the optical plate 34 of the excitation light conversion device 32. The first optical path combining member 41 transmits the red light emitted from the light source 31 toward the second optical path combining member 42. The first optical path synthesis member 41 reflects the fluorescence (green light) generated by the phosphor layer 34 e of the optical plate 34 toward the second optical path synthesis member 42. Thereby, the optical path of the fluorescence generated by the phosphor layer 34 e of the optical plate 34 is combined with the optical path of red light emitted by the light source 31.

  The first reflecting mirror 43 is disposed on the opposite side of the first optical path combining member 41 with respect to the optical plate 34. The first reflecting mirror 43 is provided perpendicular to the first optical path combining member 41. The first reflection mirror 43 is orthogonal to the optical axis of the excitation light emitted by the excitation light generator 10. Further, the first reflecting mirror 43 obliquely crosses at 45 ° with respect to the optical axis of the diffusely transmitted light that has passed through the diffuser-transmitting plate 34 f of the optical plate 34.

  The first reflection mirror 43 reflects the diffuse transmission light that has passed through the diffusion transmission plate 34 f of the optical plate 34 toward the second reflection mirror 44. The optical axis of the diffusely transmitted light reflected by the first reflecting mirror 43 is parallel to the optical axes of the fluorescent light and red light whose optical paths are combined by the first optical path combining member 41. The traveling direction of the diffusely transmitted light reflected by the first reflecting mirror 43 is the same as the traveling direction of the fluorescence and red light whose optical paths are combined by the first optical path combining member 41.

  The second reflection mirror 44 is provided in parallel to the first optical path combining member 41. The second reflection mirror 44 is provided perpendicular to the first reflection mirror 43. The second reflecting mirror 44 shields light at 45 ° with respect to the optical axis of the diffusely transmitted light reflected by the first reflecting mirror 43.

  The second reflection mirror 44 reflects the diffuse transmitted light reflected by the first reflection mirror 43 toward the second optical path combining member 42. The optical axis of the diffusely transmitted light reflected by the second reflecting mirror 44 is orthogonal to the optical axes of the fluorescent light and red light whose optical paths are combined by the first optical path combining member 41.

  The second optical path combining member 42 is disposed on the opposite side of the light source 31 with respect to the first optical path combining member 41. The second optical path combining member 42 and the first optical path combining member 41 are provided in parallel to each other. The second optical path combining member 42 is disposed at the intersection of the optical axes of the fluorescent light and red light whose optical paths are combined by the first optical path combining member 41 and the optical axis of the diffusely transmitted light reflected by the second reflecting mirror 44. ing. The second optical path combining member 42 crosses at 45 ° with respect to the optical axes of the fluorescent light and red light whose optical paths are combined by the first optical path combining member 41. The second optical path synthesis member 42 crosses at 45 ° with respect to the optical axis of the diffusely transmitted light reflected by the second reflecting mirror 44.

  The second optical path combining member 42 is a dichroic mirror. The second optical path combining member 42 transmits light in a predetermined band (blue light) and reflects light (red light, green light) outside the predetermined band. Specifically, the second optical path combining member 42 reflects the fluorescence (green light) reflected by the first optical path combining member 41 toward the light guide device 2a. The second optical path combining member 42 reflects the red light that has passed through the first optical path combining member 41 toward the light guide device 2a. Further, the second optical path combining member 42 transmits the diffuse transmitted light (blue light) reflected by the second reflecting mirror 44 toward the light guide device 2a. As a result, the red light and the fluorescent light whose optical paths are combined by the first optical path combining member 41 are combined with the optical path of the blue light reflected by the second reflecting mirror 44.

-Condensing optical system 50

The condensing optical system 50 includes a plurality of lenses 51 to 59.
Lenses 51 and 52 are disposed between the light source 31 and the first optical path combining member 41. The lens 53 is disposed between the first optical path combining member 41 and the second optical path combining member 42. The lenses 51 to 53 are arranged so that these optical axes overlap.

  Lenses 55 and 56 are disposed between the optical plate 34 and the first optical path combining member 41. A lens 57 is disposed between the optical plate 34 and the first reflecting mirror 43. The lenses 55, 56, 57 and the reduction optical system 20 are arranged so that their optical axes overlap.

  A lens 58 is disposed between the first reflection mirror 43 and the second reflection mirror 44. The optical axis of the lens 58 and the optical axis of the lens 57 are orthogonal to each other in the first reflection mirror 43. A lens 59 is disposed between the second reflecting mirror 44 and the second optical path combining member 42. The optical axis of the lens 59 and the optical axis of the lens 58 are orthogonal to each other in the second reflecting mirror 44. The lens 54 is disposed between the second optical path combining member 42 and the light guide device 2a. The lenses 54 and 59 are arranged so that these optical axes overlap. The optical axes of the lenses 54 and 59 are orthogonal to the optical axis of the lens 53 in the second optical path combining member 42.

・ Phase sensor 72

  The phase sensor 72 detects the phase during the rotation period of the spindle motor 33 or the optical plate 34. The phase detected by the phase sensor 72 is output to the light source controller 70. For example, the phase sensor 72 is a rotary encoder.

・ Motor driver 71

  The motor driver 71 drives the spindle motor 33 in accordance with a command from the light source control unit 70.

Light source control unit 70

  The light source control unit 70 includes a microcomputer. The light source controller 70 inputs the phase detected by the phase sensor 72 (the phase during the rotation period of the spindle motor 33 or the optical plate 34). The light source control unit 70 receives the phase (phase in the cycle of the display element 3) output by the display controller 92.

  The light source controller 70 feedback-controls the spindle motor 33 based on the phase input from the phase sensor 72 (the phase during the rotation cycle of the spindle motor 33 or the optical plate 34). For example, the light source control unit 70 controls the spindle motor 33 at a constant speed, and changes / adjusts the rotation cycle / rotation speed of the spindle motor 33. Further, the light source control unit 70 blinks the light source 31 and the excitation light generator 10 (excitation light source 11).

-About the period of the display element 3, the blinking period of the light source 31, the blinking period of the excitation light generator 10, and the rotation period of the optical plate 34 (the rotation period of the optical plate 34 is an even number of the period of the display element 3 (however, If it is an even fraction of 2)

  FIG. 4 is a timing chart showing time on the horizontal axis. In the following description, n is a natural number.

  In FIG. 4, the rotation period of the optical plate 34 and the spindle motor 33 is one half of the period of the display element 3, and a period in which a color image of one frame is generated by the display element 3 (hereinafter referred to as one frame period). )), The spindle motor 33 rotates twice. Therefore, during one frame period, the phosphor layer 34e passes the optical axis of the excitation light twice. Also, during one frame period, the diffuse transmission plate 34f passes through the optical axis of the excitation light twice.

  One frame period is equal to the period of the display element 3. During one frame period, the display element 3 generates a green image, a blue image, a red image, and a blue image in this order. And the display element 3 repeats the event which produces | generates a green image, a blue image, a red image, and a blue image in these order.

  The light source control unit 70 controls the spindle motor 33 based on the phase input from the display controller 92 (the phase in the cycle of the display element 3), thereby starting the rotation cycle of the optical plate 34 (phase is zero). Synchronize with the start of the cycle of the display element 3 (phase is zero).

  The display element 3 generates a green image in synchronization with a period in which the phosphor layer 34e passes the optical axis of the excitation light for the first time (odd number) in one frame period. The display element 3 generates a blue image in synchronization with a period in which the diffuse transmission plate 34f passes the optical axis of the excitation light first (odd number) and second (even number) in one frame period. The display element 3 generates a red image in synchronization with a period in which the phosphor layer 34e passes the optical axis of the excitation light for the second time (even number) in one frame period.

  The light source control unit 70 controls the blinking period of the excitation light generator 10 (particularly the excitation light source 11) based on the phase input from the display controller 92 (the phase that is present in the period of the display element 3). The start of the blinking cycle of the generator 10 (phase is zero) is synchronized with the start of the cycle of the display element 3 (phase is zero). Therefore, the light source control unit 70 synchronizes the start of the blinking cycle of the excitation light generator 10 and the start of the rotation cycle of the spindle motor 33 (rotation cycle of the optical plate 34).

  The blinking cycle of the excitation light generator 10 is constant. The blinking cycle of the excitation light generator 10 and the cycle of the display element 3 are equal to each other. The blinking cycle of the excitation light generator 10 is twice the rotation cycle of the optical plate 34 and the spindle motor 33, and the rotation speed (the number of rotations per unit time) of the optical plate 34 and the spindle motor 33 is that of the excitation light generator 10. It is twice the blinking speed (number of blinks per unit time). The light source controller 70 controls the blinking cycle of the excitation light generator 10 to be twice the rotation cycle of the optical plate 34 and the spindle motor 33.

  The excitation light generator 10 is turned on in synchronization with the period in which the display element 3 generates the green image and the first and second blue images in one frame period. That is, during the period in which the phosphor layer 34e passes the optical axis of the excitation light for the first time in one frame period, during the period in which the diffuse transmission plate 34f passes the optical axis of the excitation light for the first time in one frame period, And the excitation light generator 10 lights up during the period when the diffuse transmission plate 34f passes the optical axis of the excitation light for the second time in one frame period.

  On the other hand, the excitation light generator 10 is turned off in synchronization with the period during which the display element 3 generates a red video. That is, the excitation light generating device 10 is turned off in synchronization with the period when the phosphor layer 34e passes the optical axis of the excitation light for the second time in one frame period.

  Therefore, the light source device 1 emits fluorescence (green light) in synchronization with the period in which the display element 3 generates a green image. In addition, the light source device 1 emits diffuse transmitted light (blue light) in synchronization with a period in which the display element 3 generates the first and second blue images.

  The light source control unit 70 controls the blinking cycle of the light source 31 based on the phase input from the display controller 92 (the phase that is present in the cycle of the display element 3), thereby starting the blinking cycle of the light source 31 (the phase is zero). ) Is synchronized with the start of the cycle of the display element 3 (phase is zero). Therefore, the light source controller 70 synchronizes the start of the blinking cycle of the light source 31 and the start of the rotation cycle of the spindle motor 33 (rotation cycle of the optical plate 34). Further, the light source control unit 70 synchronizes the start of the blinking cycle of the light source 31 and the start of the rotation cycle of the excitation light generator 10.

  The blinking cycle of the light source 31 is constant. The blinking cycle of the light source 31, the blinking cycle of the excitation light generator 10, and the cycle of the display element 3 are equal to each other. The blinking cycle of the light source 31 is twice the rotation cycle of the optical plate 34 and the spindle motor 33, and the rotation speed (the number of rotations per unit time) of the optical plate 34 and the spindle motor 33 is the blinking speed of the light source 31 (per unit time). Twice the number of blinks). The light source controller 70 controls the blinking cycle of the light source 31 to be twice the rotation cycle of the optical plate 34 and the spindle motor 33.

  The light source 31 blinks at a phase opposite to that of the excitation light generator 10. That is, the light source 31 is turned on in synchronization with the excitation light generator 10 being turned off, and the light source 31 is turned off in synchronization with the excitation light generator 10 being turned on. The light source controller 70 controls the blinking of the excitation light generator 10 and the blinking of the light source 31 to have opposite phases.

  The light source 31 is turned on in synchronization with the period during which the display element 3 generates a red video. That is, the light source 31 is turned on in synchronization with the period when the phosphor layer 34e passes the optical axis of the excitation light for the second time in one frame period.

  On the other hand, the light source 31 is turned off in synchronization with the period in which the display element 3 generates the green image and the first and second blue images in one frame period. That is, during the period in which the phosphor layer 34e passes the optical axis of the excitation light for the first time in one frame period, during the period in which the diffuse transmission plate 34f passes the optical axis of the excitation light for the first time in one frame period, In addition, the light source 31 is turned off in synchronization with a period during which the diffuse transmission plate 34f passes the optical axis of the excitation light for the second time in one frame period.

  Therefore, the excitation light generating device 10 and the light source 31 are continuously turned on during the period from when the phosphor layer 34e starts to pass through the optical axis of the excitation light until it finishes passing, once during one frame period. is there. The excitation light generator 10 and the light source 31 continue to be turned off once during one frame period during the period from when the phosphor layer 34e starts to pass through the optical axis of the excitation light to when it finishes passing. Further, during the period from when the diffuse transmission plate 34f starts to pass through the optical axis of the excitation light to when it finishes passing, the lighting of the excitation light generator 10 and the extinction of the light source 31 are continued twice during one frame period. is there.

  As described above, the rotation speed of the optical plate 34 and the spindle motor 33 becomes twice the blinking speed of the excitation light generator 10, and the optical plate 34 rotates at a high speed. The area irradiated to the layer 34e is increased. That is, the energy of the excitation light applied to the phosphor layer 34e is dispersed in the circumferential direction. Therefore, the temperature rise of the phosphor layer 34e can be suppressed, and the occurrence of luminance saturation of the phosphor layer 34e can be suppressed. Luminance saturation refers to a phenomenon in which the fluorescence intensity does not increase with an increase in the energy density degree when the energy density of the irradiated excitation light exceeds a certain value.

  The phosphor layer 34e is irradiated with the excitation light until the phosphor layer 34e starts to pass through the optical axis of the excitation light and finishes passing (however, the first time in one frame period). That is, the entire circumferential direction of the phosphor layer 34e is used as an excitation light irradiation region. Therefore, local temperature rise and deterioration of the phosphor layer 34e can be suppressed, and the lifetime of the phosphor layer 34e is prolonged.

  The blinking cycle of the excitation light generator 10 is twice the rotation cycle of the optical plate 34 and the spindle motor 33, and the phosphor layer 34e starts to pass through the optical axis of the excitation light until it finishes passing (however, one frame period) The second time), the excitation light generator 10 is turned off. Therefore, the period can be used as the red light emission period and the air cooling period of the phosphor layer 34e.

  Since the number of times blue light (diffuse transmitted light) is emitted and the number of times blue image is generated is twice per frame period, so-called color braking can be suppressed. Color braking means that the colors of the projected color image appear to be separated in time, resulting in a rainbow-like afterimage that is not an element of the color image.

  Next, a case where the rotation cycle of the spindle motor 33 and the optical plate 34 is an even number of 4 or more of the cycle of the display element 3 will be described with reference to FIG. FIG. 5 is a timing chart showing time on the horizontal axis.

  The display element 3 generates a green image in synchronization with a period in which the phosphor layer 34e passes through the optical axis of the excitation light an odd number of times in one frame period. The display element 3 generates a blue image in synchronization with a period in which the diffuse transmission plate 34f passes the optical axis of the excitation light in the odd-numbered and even-numbered times in one frame period. The display element 3 generates a red image in synchronization with a period in which the phosphor layer 34e passes through the optical axis of the excitation light for an even number of times in one frame period.

  The blinking cycle of the excitation light generator 10 is constant. The blinking period of the excitation light generator 10 is twice the rotation period of the optical plate 34 and the spindle motor 33, and the rotation speed of the optical plate 34 and the spindle motor 33 is twice the blinking speed of the excitation light generator 10. The light source controller 70 controls the blinking cycle of the excitation light generator 10 to be twice the rotation cycle of the optical plate 34 and the spindle motor 33.

  If the rotation period of the optical plate 34 and the spindle motor 33 is 1 / (2 × n) of the period of the display element 3, the blinking period of the excitation light generator 10 is 1 / n of the period of the display element 3. (This is not limited to the case where the rotation period of the optical plate 34 and the spindle motor 33 is an even number of 4 or more of the period of the display element 3. This is also true when the period of 3 is 1/2.)

  The excitation light generator 10 is turned on in synchronization with a period in which the display element 3 generates each green image and each blue image during one frame period. That is, the period during which the phosphor layer 34e passes the optical axis of the excitation light an odd number of times during one frame period, and the period during which the diffuse transmission plate 34f passes the optical axis of the excitation light at each time during the one frame period. The excitation light generator 10 is turned on.

  On the other hand, the excitation light generator 10 is turned off in synchronization with the period in which the display element 3 generates the red image for each time in one frame period. That is, the excitation light generating device 10 is turned off in synchronization with a period in which the phosphor layer 34e passes the optical axis of the excitation light at an even number of times in one frame period.

  The blinking cycle of the light source 31 is constant. The blinking cycle of the light source 31 is twice the rotation cycle of the optical plate 34 and the spindle motor 33, and the rotation speed of the optical plate 34 and the spindle motor 33 is twice the blinking rate of the light source 31. The light source controller 70 controls the blinking cycle of the light source 31 to be twice the rotation cycle of the optical plate 34 and the spindle motor 33.

  If the rotation period of the optical plate 34 and the spindle motor 33 is 1 / (2 × n) of the period of the display element 3, the blinking period of the light source 31 is 1 / n of the period of the display element 3 (this This is not limited to the case where the rotation cycle of the optical plate 34 and the spindle motor 33 is an even number of 4 or more of the cycle of the display element 3, and the rotation cycle of the optical plate 34 and the spindle motor 33 is the cycle of the display element 3. This is also true when it is a half of.

  The light source 31 is turned on in synchronization with a period in which the display element 3 generates a red image for each time in one frame period. That is, the light source 31 is turned on in synchronization with a period in which the phosphor layer 34e passes through the optical axis of the excitation light an even number of times during one frame period.

  On the other hand, the light source 31 is turned off in synchronization with a period in which the display element 3 generates each green image and each blue image in one frame period. That is, the period during which the phosphor layer 34e passes the optical axis of the excitation light an odd number of times during one frame period, and the period during which the diffuse transmission plate 34f passes the optical axis of the excitation light at each time during the one frame period. Inside, the light source 31 is turned off.

  Therefore, if the rotation period of the optical plate 34 and the spindle motor 33 is 1 / (2 × n) of the period of the display element 3, the phosphor layer 34e starts to pass through the optical axis of the excitation light and then passes through. It is n times during one frame period that the excitation light generating device 10 is continuously turned on and the light source 31 is turned off during the period up to. Further, the excitation light generating device 10 and the light source 31 continue to be turned off during the period from when the phosphor layer 34e starts to pass through the optical axis of the excitation light to when it finishes passing, n times during one frame period. is there. In addition, the fact that the excitation light generator 10 and the light source 31 are continuously turned on during the period from when the diffusive transmission plate 34f starts to pass through the optical axis of the excitation light to when it finishes passing is indicated as (2 Xn) There are times. This is also true when the rotation period of the optical plate 34 and the spindle motor 33 is half the period of the display element 3 (when n is 1).

  As described above, even if the rotation period of the optical plate 34 and the spindle motor 33 is one-fourth or more of the period of the display element 3, it is possible to suppress the temperature rise of the phosphor layer 34e and Generation of luminance saturation of the body layer 34e can be suppressed. Furthermore, local temperature rise and deterioration of the phosphor layer 34e can be suppressed, and the lifetime of the phosphor layer 34e is prolonged.

  Further, if the cycle of the display element 3 is (2 × n) times the rotation cycle of the optical plate 34 and the spindle motor 33, the number of times of emitting blue light and the number of times of generating blue video are (2 × n) times. In addition, the number of times green light is emitted, the number of times red light is emitted, the number of times green image is generated, and the number of times red image is generated is n times (the period of the display element 3 is four or more of the rotation period of the optical plate 34 and spindle motor 33) N is a value of 2 or more). Therefore, color braking can be suppressed.

  In the above description, the display element 3 generates a green image and the light source 31 is turned off in synchronization with a period in which the phosphor layer 34e passes the optical axis of the excitation light “odd” times in one frame. Further, the excitation light generator 10 is turned on. On the other hand, in synchronization with the period when the phosphor layer 34e passes through the optical axis of the excitation light “even” times in one frame period, the display element 3 generates a green image, the light source 31 is turned off, The excitation light generator 10 may be turned on. In this case, in synchronization with the period when the phosphor layer 34e passes through the optical axis of the excitation light in the “odd” number of times in one frame period, the display element 3 generates a red image, the light source 31 is turned on, The excitation light generator 10 is turned off. Further, the display element 3 generates a blue image, the light source 31 is turned off, and the excitation light generator 10 synchronizes with the period when the diffuse transmission plate 34f passes the optical axis of the excitation light each time in one frame period. Lights up.

-About the period of the display element 3, the blinking period of the light source 31, the blinking period of the excitation light generator 10, and the rotation period of the optical plate 34 (the rotation period of the optical plate 34 is an odd number of the period of the display element 3 (however, 3 or more Odd number)

  FIG. 6 is a timing chart showing time on the horizontal axis.

  In FIG. 6, the rotation period of the optical plate 34 and the spindle motor 33 is (2 × n + 1) times the period of the display element 3, and the spindle during the period in which a color image of one frame is generated by the display element 3. The motor 33 rotates (2 × n + 1) times. Therefore, the phosphor layer 34e passes through the optical axis of the excitation light (2 × n + 1) times during the period in which one color image is generated by the display element 3. Further, during the period in which a color image of one frame is generated by the display element 3, the diffuse transmission plate 34f passes through the optical axis of the excitation light (2 × n + 1) times.

  In one frame period, the display element 3 generates a green image (n + 1) times, a blue image (2 × n + 1 times), and a red image (n + 1) times. Therefore, color braking can be suppressed.

  The display element 3 generates a green image in synchronization with a period in which the phosphor layer 34e passes the optical axis of the excitation light in an odd number of times in one frame period (excluding the last time in one frame period). In the first half of the period in which the phosphor layer 34e passes the optical axis of the excitation light in the final time in one frame period, the display element 3 generates a red video, and in the second half of the period, the display element 3 generates a green video. To do. The display element 3 generates a blue image in synchronization with a period in which the diffuse transmission plate 34f passes the optical axis of the excitation light in the odd-numbered and even-numbered times in one frame period. The display element 3 generates a red image in synchronization with a period in which the phosphor layer 34e passes through the optical axis of the excitation light for an even number of times in one frame period.

  During the period when the phosphor layer 34e passes the optical axis of the excitation light in an odd number of times in one frame period (except for the last time in one frame period), and the diffuse transmission plate 34f changes the optical axis of the excitation light. The excitation light generator 10 is lit during the period of passing each time during one frame period.

  The excitation light generator 10 is turned off in synchronization with the period when the phosphor layer 34e passes through the optical axis of the excitation light for the even number of times in one frame period.

  In the first half of the period in which the phosphor layer 34e passes the optical axis of the excitation light in the final time in one frame period, the excitation light generation apparatus 10 is turned off, and in the second half of the period, the excitation light generation apparatus 10 is turned on.

  The light source 31 blinks at a phase opposite to that of the excitation light generator 10. That is, the light source 31 is turned on in synchronization with the excitation light generator 10 being turned off, and the light source 31 is turned off in synchronization with the excitation light generator 10 being turned on.

  During the period when the phosphor layer 34e passes the optical axis of the excitation light in an odd number of times in one frame period (except for the last time in one frame period), and the diffuse transmission plate 34f changes the optical axis of the excitation light. The light source 31 is turned off during the period of passing each time during one frame period.

  The light source 31 is turned on in synchronization with a period in which the phosphor layer 34e passes the optical axis of the excitation light for an even number of times in one frame period.

  The light source 31 is turned on in the first half of the period in which the phosphor layer 34e passes the optical axis of the excitation light in the last round of one frame period, and the light source 31 is turned off in the second half of the period.

  Therefore, assuming that the rotation period of the optical plate 34 and the spindle motor 33 is 1 / (2 × n + 1) times the period of the display element 3, the phosphor layer 34e starts to pass through the optical axis of the excitation light and then passes through. It is n times during one frame period that the excitation light generating device 10 is continuously turned on and the light source 31 is turned off during the period up to. Further, the excitation light generating device 10 and the light source 31 continue to be turned off during the period from when the phosphor layer 34e starts to pass through the optical axis of the excitation light to when it finishes passing, n times during one frame period. is there.

  In the above-described embodiment, the blinking cycle of the excitation light generator 10 is twice the rotation cycle of the optical plate 34 and the spindle motor 33. If the blinking cycle of the excitation light generator 10 is an even multiple of the rotation cycle of the optical plate 34 and the spindle motor 33, it is not limited to twice.

Embodiments of the present invention have been described. The scope of the present invention is not limited to the embodiments described above, but includes the scope of the invention described in the claims and the equivalents thereof.
The invention described in the scope of claims attached to the application of this application will be added below. The item numbers of the claims described in the appendix are as set forth in the claims attached to the application of this application.
[Appendix]
<Claim 1>
An excitation light generator that emits excitation light;
An optical plate that intersects the optical axis of the excitation light and is provided with a fluorescent region and a light diffusion transmission region along a circumferential direction passing through the intersection;
A rotation driver for rotating the optical plate in the circumferential direction;
A light source controller that controls the excitation light generator and the rotation driver,
The light source control unit controls the rotation driver so as to control the rotation period of the optical plate to be an integer of 2 or more of one frame period in which one frame of video is generated. Rotate,
The light source controller performs at least once during the one frame period to turn on the excitation light generator during a period from when the fluorescent region starts to pass through the optical axis of the excitation light to when it finishes passing, Performing one or more times during the one frame period to turn off the excitation light generator during a period from when the fluorescent region starts to pass through the optical axis of the excitation light to when it finishes passing,
A light source device characterized by that.
<Claim 2>
The light source control unit turns on the excitation light generation device during a period in which the light diffusion transmission region passes through the optical axis of the excitation light.
The light source device according to claim 1.
<Claim 3>
The light source control unit turns on the excitation light generating device during the period in which the light diffusion transmission region passes through the optical axis of the excitation light, and performs the number of times that is an integer multiple during the one frame period.
The light source device according to claim 2.
<Claim 4>
A light source that emits light of a different color from the excitation light;
The light source control unit turns off the excitation light generator and turns on the light source during a period from when the fluorescent region starts to pass through the optical axis of the excitation light to when it passes through, and the fluorescent region is turned on by the excitation region. 4. The light source according to claim 1, wherein the excitation light generator is turned on and the light source is turned off during a period from the start of passing through the optical axis to the end of passage of light. apparatus.
<Claim 5>
The light source control unit turns off the light source during a period in which the light diffusion transmission region passes through the optical axis of the excitation light.
The light source device according to claim 4.
<Claim 6>
A light source device according to any one of claims 1 to 5;
A display element that is irradiated with light emitted from the light source device and divides one frame image into a plurality of color images in time to generate a plurality of color images during one frame period;
A projection optical system for projecting an image generated by the display element;
Comprising
A projection apparatus characterized by that.
<Claim 7>
An excitation light generator that emits excitation light;
An optical plate that intersects the optical axis of the excitation light and is provided with a fluorescent region and a light diffusion transmission region along a circumferential direction passing through the intersecting point;
A rotation driver for rotating the optical plate in the circumferential direction;
A light source control unit that rotates the rotation driver at an equal speed and blinks the excitation light generation device at a cycle that is an even multiple of the rotation cycle of the optical plate;
The light source control unit turns off the excitation light generator during a period in which the fluorescent region passes through the optical axis of the excitation light once in one blinking cycle of the excitation light generator, and the light source control unit during the remaining period Turn on the excitation light generator,
A light source device characterized by that.
<Claim 8>
A light source that emits light of a different color from the excitation light;
The light source control unit causes the light source to blink at a cycle equal to the blinking cycle of the excitation light generation device and at a phase opposite to the blinking of the excitation light generation device;
The light source device according to claim 7.
<Claim 9>
The light source device according to claim 7 or 8,
A display element that is irradiated with light emitted from the light source device and divides one frame image into a plurality of color images in time to generate a plurality of color images during one frame period;
A projection optical system for projecting an image generated by the display element;
With
The period of one frame of the display element is a natural number multiple of the blinking period of the excitation light generator,
A projection apparatus characterized by that.

DESCRIPTION OF SYMBOLS 1 Light source device 3 Display element 4 Projection optical system 10 Excitation light generator 31 Light source 33 Spindle motor (rotation drive)
34 Optical plate 34a First segment (fluorescence region)
34b Second segment (light diffusion region)
34e phosphor layer 34f light diffusion transmission plate 70 light source control unit

Claims (4)

An excitation light generator that emits excitation light;
An optical plate that intersects the optical axis of the excitation light and is provided with a fluorescent region and a light diffusion transmission region along a circumferential direction passing through the intersection;
A rotation driver for rotating the optical plate in the circumferential direction;
A light source controller that controls the excitation light generator and the rotation driver,
The light source control unit, during one frame period in which one frame image is generated, the rotation driving device to control the, rotates the optical plate many times the number of 2 or more integer multiples,
The light source controller performs at least once during the one frame period to turn on the excitation light generator during a period from when the fluorescent region starts to pass through the optical axis of the excitation light to when it finishes passing, Performing at least once during the one frame period to turn off the excitation light generator during a period from when the fluorescent region starts to pass through the optical axis of the excitation light to when it finishes passing ,
The light source control unit turns on the excitation light generating device during the period in which the light diffusion transmission region passes through the optical axis of the excitation light, and performs the number of times that is an integer multiple during the one frame period .
A light source device characterized by that. A light source that emits light of a different color from the excitation light;
The light source controller is
During the period until the fluorescent region finishes passing from the start of passing through the optical axis of the excitation light, to light the light source in the case of Ru turn off the excitation light generator, lights the pre Symbol excitation light generator the light source device according to claim 1, characterized in that turns off the light source when Ru is. The light source control unit turns off the light source during a period in which the light diffusion transmission region passes through the optical axis of the excitation light.
The light source device according to claim 2 . The light source device according to any one of claims 1 to 3 ,
A display element that is irradiated with light emitted from the light source device and divides one frame image into a plurality of color images in time to generate a plurality of color images during one frame period;
A projection optical system for projecting an image generated by the display element;
Comprising
A projection apparatus characterized by that.

Images