JP2014132289A - Projector and control method of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To bring the brightness of an image to be displayed close to the desired brightness.SOLUTION: A projector includes a reflection type liquid crystal panel 4R that modulates light emitted from a light source on the basis of an image signal indicating an image to be projected, and an adjustment unit 70 that adjusts the output of the light source in reference to the image signal.

Description

  The present invention relates to a projector and a control method thereof.

  The projector includes a light source, a light modulation device, and a projection lens. The light emitted from the light source is modulated by the light modulation device, and the modulated light is projected onto the screen by the projection lens, whereby an image is displayed on the screen. indicate. A conventional projector includes a halogen lamp, a metal halide lamp, and a high-pressure mercury lamp as a light source. Recently, a projector having a solid-state light source such as a laser diode or a light emitting diode has been developed.

  Patent Document 1 discloses a solid-state light source that emits excitation light, a phosphor that converts the excitation light into fluorescence, a light modulation device that modulates light from the phosphor, and light modulated by the light modulation device. A projector including a projection optical system that projects a projection onto a screen is disclosed. Further, it is disclosed that the projector of Patent Document 1 includes an optical sensor that detects at least one of the excitation light via the phosphor and the fluorescence converted by the phosphor. Moreover, in the projector of Patent Document 1, a control device that controls at least one of the solid-state light source and the light modulation device according to the detection result of the light sensor is disclosed.

JP2012-47951A

  Light reflection or absorption occurs when the light modulator modulates the light. Accordingly, there is a problem that the brightness of the image displayed by the projector is different from the desired brightness.

  Accordingly, an aspect of the present invention has been made in view of the above problems, and an object of the present invention is to provide a projector that can bring the brightness of an image to be displayed closer to a desired brightness and a control method thereof. .

  (1) In one embodiment of the present invention, an optical modulation unit that modulates light emitted from a light source based on an image signal indicating an image to be projected, and an output of the light source is adjusted with reference to the image signal And a control unit. As a result, even if light reflection or absorption occurs when the light modulation unit modulates light, the projector adjusts the output of the light source to adjust the brightness of the image indicated by the image signal to a desired brightness. Can be approached.

  (2) Moreover, one aspect of the present invention is the above-described projector, further including a light detection unit that detects light brightness information related to the brightness of light emitted from the light source, and the adjustment unit includes: According to the image signal, the light brightness information detected by the light detection unit is corrected, and the output of the light source is adjusted with reference to the corrected light brightness information. As a result, even if light reflection or absorption occurs when the light modulation unit modulates light, the projector corrects the light brightness information detected by the light detection unit according to the image signal, and By adjusting the output of the light source with reference to the light brightness information, the brightness of the image indicated by the image signal can be brought close to the desired brightness.

  (3) One embodiment of the present invention is the above-described projector, in which the light detection unit detects the light brightness information with respect to light included in an optical path from the light source to the light modulation unit. As a result, even if light reflection or absorption occurs when the light modulation unit modulates light, the projector determines the light brightness of the light included in the optical path from the light source to the light modulation unit according to the image signal. By correcting the information and adjusting the output of the light source with reference to the corrected light brightness information, the brightness of the image indicated by the image signal can be brought close to the desired brightness.

  (4) One embodiment of the present invention is the above-described projector, wherein the adjustment unit corrects the light brightness information detected by the light detection unit in accordance with information about the brightness of the image signal. . As a result, even if light reflection or absorption occurs when the light modulation unit modulates light, the projector corrects the light brightness information detected by the light detection unit according to the information related to the brightness of the image signal. Then, by adjusting the output of the light source with reference to the corrected light brightness information, the brightness of the image indicated by the image signal can be brought close to the desired brightness.

  (5) One embodiment of the present invention is the above-described projector, in which the light detection unit detects light brightness information for each color of light, and the adjustment unit includes a color included in the image signal. The light brightness information of the color of the corresponding light detected by the light detection unit is corrected according to the information regarding the brightness for each. Accordingly, the light intensity of the target color can be corrected according to the brightness of the target color in the image signal, and the light emission intensity of the light source can be adjusted with reference to the corrected light intensity. Therefore, the projector can bring the brightness of the image indicated by the image signal for each color closer to the desired brightness.

  (6) One embodiment of the present invention is the above-described projector, in which the adjustment unit converts information relating to brightness of one color included in the image signal into reflection information indicating reflection of the light modulation unit. A conversion unit for converting, and a correction processing unit for correcting the light brightness information of the one color detected by the light detection unit according to the reflection information obtained by conversion by the conversion unit. Thereby, the correction processing unit can correct the light brightness information of one color by the same process regardless of the setting of the color mode, for example. As a result, the correction processing unit can correct the light brightness information of one color using, for example, a common correction table regardless of the color mode setting. Therefore, the number of tables held by the correction processing unit can be reduced, and the capacity of the memory held in the correction processing unit can be reduced.

  (7) One aspect of the present invention is the above-described projector, wherein the information regarding the brightness for each color of the image signal is an average gradation value for each color of the image signal. Thereby, the brightness for each color of the image signal can be accurately determined by setting the brightness for each color of the image signal as the average gradation value for each color of the image signal.

  (8) According to another aspect of the present invention, there is provided a projector control method including a light modulation unit that modulates light emitted from a light source based on an image signal indicating an image to be projected. The projector control method includes a procedure for adjusting the output of the light source. As a result, even if light reflection or absorption occurs when the light modulation unit modulates light, the projector adjusts the output of the light source to adjust the brightness of the image indicated by the image signal to a desired brightness. Can be approached.

It is a schematic block diagram which shows the structure of the projector in 1st Embodiment. It is a schematic block diagram which shows the structure of the control part in 1st Embodiment. It is a schematic block diagram which shows the structure of the correction | amendment part in 1st Embodiment. It is a figure which shows the relationship between a correction coefficient and APL. It is a flowchart which shows an example of the flow of a process of the control part in 1st Embodiment. It is a schematic block diagram which shows the structure of the projector in 2nd Embodiment. It is a schematic block diagram which shows the structure of the control part in 2nd Embodiment. It is a schematic block diagram which shows the structure of the correction | amendment part in 2nd Embodiment. It is a flowchart which shows an example of the flow of a process of the control part in 2nd Embodiment.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a schematic block diagram illustrating the configuration of the projector 50 according to the first embodiment. As shown in FIG. 1, the projector 50 includes a blue light illumination device 51, a yellow light illumination device 52, a dichroic mirror 25, a light guide optical system 3R, a light guide optical system 3G, and a light guide optical system. 3B, a reflective liquid crystal panel (light modulator) 4R, a reflective liquid crystal panel (light modulator) 4G, a reflective liquid crystal panel (light modulator) 4B, a red light photosensor 36R, and a green light The optical sensor 36G, the blue light optical sensor 36B, the cross dichroic prism 5, and the projection optical system 6 are provided. As an example, the blue light illumination device 51 emits mainly P-polarized blue light LB. As an example, the yellow light illumination device 52 emits mainly P-polarized yellow light LY.

  The dichroic mirror 25 is an optical element in which a wavelength selection film that reflects a light beam in a predetermined wavelength region and transmits a light beam in another wavelength region is formed on a substrate. In the present embodiment, as an example, the dichroic mirror 25 transmits the red light LR having a wavelength longer than a predetermined reference wavelength among the yellow light LY emitted from the yellow light illumination device 52, and determines a predetermined reference. The green light LG having a wavelength shorter than the wavelength is reflected.

  The light guide optical system 3R guides S-polarized red light reflected by the polarization beam splitter 26 out of the red light LR transmitted through the dichroic mirror 25 to the red light optical sensor 36R. On the other hand, the light guide optical system 3R guides the P-polarized red light transmitted through the polarization beam splitter 26 out of the red light LR transmitted through the dichroic mirror 25 to the reflective liquid crystal panel 4R. The light guide optical system 3 </ b> R guides S-polarized red light reflected by the polarization beam splitter 26 out of the red light reflected from the reflective liquid crystal panel 4 </ b> R to the cross dichroic prism 5.

  The light guide optical system 3G guides the S-polarized green light reflected by the polarization beam splitter 27 out of the green light LG reflected by the dichroic mirror 25 to the green light optical sensor 36G. The light guide optical system 3G guides the P-polarized green light transmitted through the polarization beam splitter 27 out of the green light LG reflected by the dichroic mirror 25 to the reflective liquid crystal panel 4G. The light guide optical system 3G guides the S-polarized green light reflected by the polarization beam splitter 27 out of the green light reflected from the reflective liquid crystal panel 4G to the cross dichroic prism 5.

  The light guide optical system 3B guides the S-polarized blue light reflected by the polarization beam splitter 28 out of the blue light LB emitted by the blue light illumination device 51 to the blue light optical sensor 36B. The light guide optical system 3B guides the P-polarized blue light transmitted through the polarization beam splitter 28 out of the blue light LB emitted by the blue light illumination device 51 to the reflective liquid crystal panel 4B. The light guide optical system 3B guides S-polarized blue light reflected by the polarization beam splitter 28 out of the blue light reflected from the reflective liquid crystal panel 4B to the cross dichroic prism 5.

The reflective liquid crystal panel 4R modulates the red light guided by the light guide optical system 3R according to the image signal. Similarly, the reflective liquid crystal panel 4G modulates the green light guided by the light guide optical system 3G according to the image signal. Similarly, the reflective liquid crystal panel 4B modulates the blue light guided by the light guide optical system 3B according to the image signal.
The cross dichroic prism 5 combines the red light guided by the light guide optical system 3R, the green light guided by the light guide optical system 3G, and the blue light guided by the light guide optical system 3B. The projection optical system 6 projects the light combined by the cross dichroic prism 5 onto a projection surface such as a screen SCR.

  The red light optical sensor 36R detects the brightness of the S-polarized red light guided by the light guide optical system 3R (in this embodiment, the light intensity is an example). The red light optical sensor 36 </ b> R outputs a red light intensity signal indicating the detected light intensity of the red light to the control unit 64. Similarly, the blue light optical sensor 36B detects the brightness of the S-polarized blue light guided by the light guide optical system 3B (in this embodiment, the light intensity is an example). The blue light optical sensor 36 </ b> B outputs a blue light intensity signal indicating the detected light intensity of the blue light to the control unit 64. Similarly, the green light optical sensor 36G detects the intensity of S-polarized green light guided by the light guide optical system 3G. The green light optical sensor 36G outputs a green light intensity signal indicating the intensity of the detected green light to the control unit 64.

  The blue light illumination device 51 includes a blue laser diode array 53, a collimating lens 54, a condenser lens 55, a diffusion plate 56, a pickup lens 57, a collimating lens 58, a first lens array 9, A second lens array 10, a polarization conversion element 11, and a superimposing lens 12 are provided.

  The blue laser diode array 53 is, for example, a structure in which twelve blue laser diodes 59 are arranged in an array of 4 × 3. The same number of collimating lenses 54 as the individual blue laser diodes 59 are provided at positions corresponding to the individual blue laser diodes 59. The first lens array 9 has a plurality of first small lenses 13 for dividing the illumination light beam emitted from the collimating lens 58 into a plurality of partial light beams. The second lens array 10 has a plurality of second small lenses 14 corresponding to the plurality of first small lenses 13 of the first lens array 9. The polarization conversion element 11 converts each partial light beam from the second lens array 10 into approximately one type of linearly polarized light having a uniform polarization direction and emits the converted light. The superimposing lens 12 superimposes each partial light beam emitted from the polarization conversion element 11 in the illuminated area.

  The blue light LB emitted from the blue laser diode 59 is collimated by the collimating lens 54, then condensed by the condensing lens 55, and irradiated on the diffusion plate 56, thereby forming a point light source. Blue diffused light from each point light source on the diffusion plate 56 passes through the pickup lens 57 and is collimated by the collimating lens 58 and then enters the first lens array 9.

  The first lens array 9 has a function as a light beam splitting optical element that splits the parallel light from the parallelizing lens 58 into a plurality of partial light beams. The first lens array 9 has a configuration in which a plurality of first small lenses 13 are arranged in a matrix of a plurality of rows and a plurality of columns in a plane orthogonal to the illumination optical axis 51ax. Although not illustrated, the outer shape of the first small lens 13 is similar to the outer shape of the image forming area of the reflective liquid crystal panel 4B.

  The second lens array 10, together with the superimposing lens 12, has a function of forming an image of each first small lens 13 of the first lens array 9 in the vicinity of the image forming area of the reflective liquid crystal panel 4B. Similar to the first lens array 9, the second lens array 10 has a configuration in which a plurality of second small lenses 14 are arranged in a matrix of a plurality of rows and a plurality of columns in a plane orthogonal to the illumination optical axis 51ax.

  The polarization conversion element 11 emits the polarization direction of each partial light beam divided by the first lens array 9 as approximately one type of linearly polarized light having the same polarization direction. Of the illumination light from the blue laser diode 59, the polarization conversion element 11 transmits one polarized light (for example, P-polarized light) and reflects the other polarized light (for example, S-polarized light) in a direction perpendicular to the illumination optical axis 51ax. A polarized light separating layer, a reflecting layer that reflects light having the other polarized component reflected by the polarized light separating layer in a direction parallel to the illumination optical axis 51ax, and light having one polarized component that has passed through the polarized light separating layer. And a retardation plate that converts light into light having the other polarization component. In addition, although the light which permeate | transmitted the polarization conversion element 11 turns into P polarization substantially, not all become P polarization, and S polarization is mixed.

  The superimposing lens 12 is an optical element for condensing a plurality of partial light beams that have passed through the first lens array 9, the second lens array 10, and the polarization conversion element 11 and superimposing them on the vicinity of the image forming area of the reflective liquid crystal panel 4B. is there. The superimposing lens 12 is disposed so that the optical axis of the superimposing lens 12 and the illumination optical axis 51ax of the blue light illumination device 51 substantially coincide. The superimposing lens 12 may be composed of a compound lens in which a plurality of lenses are combined.

  The yellow light illumination device 52 includes an excitation laser diode array 60, a collimating lens 54, a condensing lens 55, a phosphor substrate 61, a pickup lens 57, a collimating lens 58, and a first lens array 9. And a second lens array 10, a polarization conversion element 11, and a superimposing lens 12. For example, the excitation laser diode array 60 includes 30 excitation laser diodes 62 arranged in an array of 6 × 5. The excitation laser diode 62 emits ultraviolet light or blue light as excitation light for exciting the phosphor. The collimating lens 54 is provided corresponding to each excitation laser diode 62. The phosphor substrate 61 is a substrate in which a phosphor layer that emits yellow light upon receiving excitation light such as ultraviolet light or blue light is formed on the substrate.

  Each excitation light emitted from the excitation laser diode 62 is collimated by the collimating lens 54, then condensed by the condensing lens 55, and irradiated onto the phosphor substrate 61 to form a point light source. The The yellow light LY emitted from each point light source on the phosphor substrate 61 passes through the pickup lens 57 and is collimated by the collimating lens 58 and then enters the first lens array 9.

  The first lens array 9, the second lens array 10, the polarization conversion element 11, and the superimposing lens 12 in the yellow light illumination device 52 are respectively the first lens array 9 and the second lens array 10 in the blue light illumination device 51. Since the configuration is the same as that of the polarization conversion element 11 and the superimposing lens 12, the description thereof is omitted. However, the yellow light illumination device 52 is different in that the illumination optical axis 51ax of the blue light illumination device 51 is changed to the illumination optical axis 52ax.

The light guide optical system 3B includes a condenser lens 32B, a first diaphragm (incident angle limiting member) 37, a polarization beam splitter (polarization separation element) 28, a second diaphragm 38, and a polarizing plate 34B. .
The condensing lens 32B converts each partial light beam of the blue light LB collected by the superimposing lens 12 into a light beam substantially parallel to each principal ray. The first stop 37 stops the substantially parallel light beam converted by the condenser lens 32B. As a result, the blue light LB collected by the superimposing lens 12 enters the polarization beam splitter 28 via the condensing lens 32B and the first diaphragm 37. At this time, the illumination light beam from the blue light illumination device 51 is aligned by the polarization conversion element 11 to approximately one type of linearly polarized light (for example, P-polarized light) whose polarization direction is substantially aligned. The passed light passes through the polarization beam splitter 28 and is incident on the blue reflective liquid crystal panel 4B. The other condenser lens 32R and condenser lens 32G are configured in the same manner as the condenser lens 32B.

  The polarization beam splitter 28 is a plate-type polarization beam splitter, and has a configuration in which a polarization separation film is provided on a translucent substrate. The polarization beam splitter 28 has a function of transmitting one polarized light and reflecting the other polarized light. In the present embodiment, the polarization beam splitter 28 has a function of transmitting P-polarized light and reflecting S-polarized light as an example. The second stop 38 stops the S-polarized blue light beam reflected by the polarization beam splitter 28. Thereby, the light narrowed down by the second diaphragm 38 is guided to the blue light optical sensor 36B.

  The polarization beam splitter 28 reflects S-polarized blue light out of the blue light reflected from the reflective liquid crystal panel 4B and transmits P-polarized blue light. Thereby, the S-polarized blue light reflected by the polarization beam splitter 28 is guided to the polarizing plate 34B. The polarizing plate 34B allows only the light polarized in a predetermined direction out of the guided blue light. Thereby, blue light polarized in a predetermined direction is guided to the cross dichroic prism 5.

Further, the P-polarized blue light transmitted through the polarization beam splitter (polarization separation element) 28 is guided to the diffusion plate 56 via the polarization conversion element 11. Here, since the diffuser plate 56 hardly reflects the P-polarized blue light thus guided, the light reflected by the diffuser plate 56 is hardly guided to the blue light optical sensor 36B.
The other polarization beam splitter (polarization separation element) 26 and polarization beam splitter (polarization separation element) 27 are also configured in the same manner as the polarization beam splitter 28 described above.

  As described above, the illumination light beam from the illuminating device 51 for blue light is substantially aligned with the P-polarized light by the polarization conversion element 11, and the blue P-polarized light is transmitted through the polarization beam splitter 28 and is reflected liquid crystal for blue light. Incident on panel 4B. However, in reality, not all the light transmitted through the polarization conversion element 11 is converted to P-polarized light, but S-polarized light is also mixed. Therefore, the S-polarized light incident on the polarization beam splitter 28 is reflected by the polarization beam splitter 28. A blue light optical sensor 36B is provided on the S-polarized light path reflected by the polarization beam splitter 28 in the blue light path.

The light guide optical system 3R includes a condenser lens 32R, a first diaphragm 37, a polarization beam splitter (polarization separation element) 26, a second diaphragm (incident angle limiting member) 38, and a polarizing plate 34R. .
The condenser lens 32R converts each partial light beam of the red light LR that has passed through the dichroic mirror 25 into a light beam that is substantially parallel to each principal ray. The first stop 37 stops the substantially parallel light beam converted by the condenser lens 32R. As a result, the red light LR that has passed through the dichroic mirror 25 enters the polarization beam splitter 26 via the condenser lens 32R and the first diaphragm 37. At this time, since the illumination light beam from the yellow light illumination device 52 is aligned with approximately one type of linearly polarized light (for example, P-polarized light) whose polarization directions are substantially aligned by the polarization conversion element 11, the condenser lens 32 </ b> R is provided. The passed light passes through the polarization beam splitter 28 and enters the reflective liquid crystal panel 4R for red light.

  The polarization beam splitter 26 has a function of transmitting P-polarized light and reflecting S-polarized light as an example. The second stop 38 stops the S-polarized red light beam reflected by the polarization beam splitter 28. Thereby, the light narrowed down by the second diaphragm 38 is guided to the red light optical sensor 36R.

  The polarization beam splitter 26 reflects S-polarized red light out of the red light reflected from the reflective liquid crystal panel 4R and transmits P-polarized red light. Accordingly, the P-polarized red light reflected by the polarization beam splitter 26 is guided to the polarizing plate 34R. The polarizing plate 34R allows only the light polarized in a predetermined direction out of the guided red light. Thereby, red light polarized in a predetermined direction is guided to the cross dichroic prism 5.

  Further, the P-polarized red light transmitted through the polarization beam splitter 26 is transmitted through the dichroic mirror 25 and guided to the phosphor substrate 61. Here, the phosphor substrate 61 reflects the guided P-polarized red light. The polarization beam splitter 26 reflects S-polarized red light out of the light reflected by the phosphor substrate 61. Thereby, the reflected red light is guided to the red light optical sensor 36R.

The light guide optical system 3G includes a condenser lens 32G, a first diaphragm 37, a polarization beam splitter (polarization separation element) 27, a second diaphragm (incident angle limiting member) 38, and a polarizing plate 34G. .
The condensing lens 32G converts each partial light beam of the green light LG reflected by the dichroic mirror 25 into a light beam substantially parallel to each principal ray. The first stop 37 stops the substantially parallel light flux converted by the condenser lens 32G. Thereby, the green light LG reflected by the dichroic mirror 25 enters the polarization beam splitter 26 via the condenser lens 32G and the first diaphragm 37. At this time, the illumination light beam from the yellow light illumination device 52 is aligned with approximately one type of linearly polarized light (for example, P-polarized light) having substantially the same polarization direction by the polarization conversion element 11, so The passed light passes through the polarization beam splitter 27 and is incident on the green reflective liquid crystal panel 4G.

  For example, the polarization beam splitter 27 transmits P-polarized light and reflects S-polarized light. The second stop 38 stops the S-polarized green light beam reflected by the polarization beam splitter 27. Thereby, the light narrowed down by the second diaphragm 38 is guided to the green light optical sensor 36G.

  The polarization beam splitter 27 reflects S-polarized green light out of the green light reflected from the reflective liquid crystal panel 4G and transmits P-polarized green light. Thereby, the S-polarized green light reflected by the polarizing beam splitter 26 is guided to the polarizing plate 34G. The polarizing plate 34G allows only the light polarized in a predetermined direction out of the guided green light. Thereby, green light polarized in a predetermined direction is guided to the cross dichroic prism 5.

  Further, the P-polarized green light transmitted by the polarization beam splitter 27 is reflected by the dichroic mirror 25 and guided to the phosphor substrate 61. Here, the phosphor substrate 61 reflects the guided P-polarized green light. The polarization beam splitter 27 reflects S-polarized green light out of the light reflected by the phosphor substrate 61. As a result, the reflected green light is guided to the green light optical sensor 36G.

The reflective liquid crystal panel 4R, the reflective liquid crystal panel 4G, and the reflective liquid crystal panel 4B modulate illumination light according to an image signal. The reflective liquid crystal panel 4 </ b> R and the reflective liquid crystal panel 4 </ b> G are light modulation units to be illuminated by the yellow light illumination device 52. The reflective liquid crystal panel 4 </ b> B is a light modulation unit to be illuminated by the blue light illumination device 51.
The reflective liquid crystal panel 4R, the reflective liquid crystal panel 4G, and the reflective liquid crystal panel 4B include a pair of substrates that sandwich the liquid crystal layer and a reflective layer (or reflective electrode) that is disposed on the substrate side facing the light incident side substrate. ) And. Further, as shown in FIG. 1, on the surface opposite to the light incident side of the reflective liquid crystal panel 4R, the reflective liquid crystal panel 4G, and the reflective liquid crystal panel 4B, the radiation fins 33R, the radiation fins 33G, and the radiation fins 33B, respectively. Is arranged.

The cross dichroic prism 5 is an optical element that synthesizes an optical image modulated for each color light emitted from the polarizing plate 34R, the polarizing plate 34G, and the polarizing plate 34B to form a color image. The cross dichroic prism 5 has a substantially square shape in plan view in which four right angle prisms are bonded together, and a dielectric multilayer film is formed on the substantially X-shaped interface in which the right angle prisms are bonded together. The dielectric multilayer film formed at one of the substantially X-shaped interfaces reflects the blue light LB, and the dielectric multilayer film formed at the other interface reflects the red light LR. By these dielectric multilayer films, the blue light LB and the red light LR are bent and aligned with the traveling direction of the green light LG that passes through the cross dichroic prism 5, thereby synthesizing three color lights.
The color image formed by the light emitted from the cross dichroic prism 5 is enlarged and projected by the projection optical system 6 to form an image on the screen SCR.

The controller 64 adjusts the light amount of the excitation laser diode 62 according to the intensity of the red light detected by the red light sensor 36R. The controller 64 adjusts the amount of light of the blue laser diode 59 according to the intensity of the blue light detected by the blue light optical sensor 36B. In addition, the control unit 64 controls the reflectance of each pixel of the reflective liquid crystal panels 4R, 4G, and 4B according to a video signal indicating an input video.
Note that the video signal input to the control unit 64 may be a plurality of image signals indicating images of successive frames or an image signal indicating an image of one frame.

  The optical configuration of each embodiment is not limited to the optical configuration of FIG. 1 and FIG. That is, the phosphor substrate 61 may be of a reflective type, and a fine optical configuration such as the presence or absence of a diffusion plate is merely a matter of design and is not limited to these. Moreover, the structure which used three LED of red (R) green (G) blue (B) as a light source may be sufficient. The light modulation unit may be a transmissive liquid crystal panel or a DMD (Digital Mirror Device, digital mirror device). The arrangement of the red light sensor 36R, the green light sensor 36G, and the blue light sensor 36B is not limited to the positions shown in FIG. 1 and FIG. Any place that can do it.

FIG. 2 is a schematic block diagram showing the configuration of the control unit 64 in the first embodiment. In the figure, in addition to the control unit 64, a light source 71 including a blue laser diode 59 and an excitation laser diode 62 is shown, a red light photosensor 36R, a green light photosensor 36G (not shown), and a blue light source. A light detection unit 72 including the light photosensor 36B is shown. The control unit 64 includes liquid crystal drive units 66R, 66G, and 66B, and an adjustment unit 70.
The adjusting unit 70 adjusts the output of the light source 71 according to the video signal. The output is, for example, brightness. The brightness is, for example, light intensity, luminance, or brightness. Here, the adjustment unit 70 includes a signal processing unit 65, a PWM signal generation unit 67, an excitation laser diode driving unit 68, and a blue laser diode driving unit 69.

The signal processing unit 65 receives a video signal and a control signal. The signal processing unit 65 applies various image quality correction processes to the received video signal, and outputs the signals after the image quality correction process to the liquid crystal driving units 66R, 66G, and 66B. Accordingly, the liquid crystal driving units 66R, 66G, and 66B control the reflectance of the reflective liquid crystal panels 4R, 4G, and 4B, respectively, using the signal input from the signal processing unit 65.
Further, the signal processing unit 65 performs processing for dimming control of the light source in accordance with the received control signal. Here, the control signal is a signal including information relating to user settings input by the user or display of the color mode on a menu screen (not shown) displayed on the screen SCR (FIG. 1). Thereby, the light source quantity is controlled based on the user setting or the brightness and color setting linked with the color mode. Further, the signal processing unit 65 performs processing for dimming control in accordance with the brightness (gradation value) of the received video signal.

  Next, a specific example of processing for light control in the signal processing unit 65 will be described. Here, the signal processing unit 65 includes a correction unit 80 and a duty determination unit 100. The correction unit 80 receives the red light intensity signal from the red light optical sensor 36R. Then, the correction unit 80 corrects the red light optical sensor value indicated by the red light intensity signal, for example, according to the color mode and the video signal included in the control signal. Then, the correction unit 80 outputs information indicating the corrected red light optical sensor value to the duty determination unit 100.

  Further, the correction unit 80 receives the blue light intensity signal from the blue light optical sensor 36B. Then, the correction unit 80 corrects the blue light optical sensor value indicated by the blue light intensity signal, for example, according to the color mode and the video signal included in the control signal. Then, the correction unit 80 outputs information indicating the corrected blue light optical sensor value to the duty determination unit 100.

  The duty determining unit 100 determines the excitation duty value DutyY and the blue duty value DutyB according to the corrected red light optical sensor value and the corrected blue light optical sensor value. At that time, the duty determination unit 100 determines the excitation duty value DutyY and the blue duty value DutyB so that the red light intensity and the blue light intensity become a predetermined target ratio. At that time, the duty determining unit 100 determines the excitation duty value DutyY and the blue duty value DutyB so as to change the intensity of the light source with high light intensity in accordance with the light source with low light intensity, for example. The duty determination unit 100 outputs information indicating the excitation duty value DutyY and information indicating the blue duty value DutyB to the PWM signal generation unit 67. Thereby, the duty determination unit 100 can control the light emission amount of the excitation laser diode 62 and the light emission amount of the blue laser diode 59.

It should be noted that the duty determination unit 100 gives a margin to the light output of the blue laser diode 59, and when the light quantity of the blue laser diode 59 decreases, the duty ratio is increased so as to increase the light intensity of the blue laser diode 59. The value DutyB may be determined.
Further, the duty determining unit 100 may determine the excitation duty value DutyY and the blue duty value DutyB so as to change the intensity of the light source with low light intensity in accordance with the light source with high light intensity, for example.

When the excitation laser diode 62 is driven at a constant current, the signal processing unit 65 outputs drive current amplitude information indicating the amplitude Y of the drive current to the excitation laser diode drive unit 68. As a result, the excitation laser diode driving unit 68 can drive the excitation laser diode 62 by constant current driving with amplitude Y in addition to PWM driving.
Similarly, when the blue laser diode 59 is driven at a constant current, the signal processing unit 65 outputs drive current amplitude information indicating the amplitude B of the drive current to the blue laser diode drive unit 69. As a result, the blue laser diode driving unit 69 can drive the blue laser diode 59 not only by PWM driving but also by constant current driving with amplitude B.

The PWM signal generation unit 67 generates a PWMY signal corresponding to the blinking of the excitation laser diode 62 from the excitation duty value DutyY. The PWM signal generation unit 67 outputs the generated PWMY signal to the excitation laser diode drive unit 68.
Similarly, the PWM signal generation unit 67 generates a PWMB signal corresponding to the blinking of the blue laser diode 59 from the blue duty value DutyB. The PWM signal generation unit 67 outputs the generated PWMB signal to the blue laser diode driving unit 69.

The excitation laser diode drive unit 68 performs ON / OFF control of the excitation laser diode 62 based on the waveform of the PWMY signal. The excitation laser diode driving unit 68 may perform constant current driving of the excitation laser diode 62 with the amplitude Y indicated by the drive current amplitude information input from the signal processing unit 65.
The blue laser diode driving unit 69 performs ON / OFF control of the blue laser diode 59 based on the waveform of the PWMB signal. The blue laser diode driving unit 69 may perform constant current driving of the blue laser diode 59 with the amplitude B indicated by the driving current amplitude information input from the signal processing unit 65.

  FIG. 3 is a schematic block diagram showing the configuration of the correction unit 80 (FIG. 2) in the first embodiment. The correction unit 80 includes a red light correction unit 81 and a blue light correction unit 91. The red light correcting unit 81 refers to the control signal and the video signal, corrects the red light optical sensor value, and generates a corrected red light optical sensor value. Here, the red light correction unit 81 includes an image analysis unit 82, a correction coefficient generation unit 83, and a multiplication unit 84.

  For example, the image analysis unit 82 averages the red gradation value of each pixel for an image of a certain frame included in the input video signal, thereby obtaining a red APL (Average Picture Level). calculate. Then, the image analysis unit 82 outputs information indicating the calculated red APL to the correction coefficient generation unit 83.

For example, the correction coefficient generation unit 83 holds a correction table in which the APL and the correction coefficient are associated with each color mode. For example, the correction coefficient generation unit 83 refers to a correction table corresponding to the color mode included in the input control signal, and calculates a correction coefficient corresponding to the red APL input from the image analysis unit 82 from the correction table. A correction coefficient is generated by reading. Then, the correction coefficient generation unit 83 outputs correction coefficient information indicating the generated correction coefficient to the multiplication unit 84.
The multiplication unit 84 generates the correction coefficient generation unit 83 using the red light photosensor value input from the red light photosensor 36R and the red light photosensor value at the timing when the image of the frame is displayed. By multiplying the correction coefficient, a corrected red light optical sensor value is generated. The multiplying unit 84 outputs information indicating the generated corrected red light optical sensor value to the duty determining unit 100.

  The blue light correction unit 91 performs the same processing as the red light correction unit 81. Specifically, the blue light correcting unit 91 refers to the control signal and the video signal, corrects the blue light optical sensor value, and generates a corrected blue light optical sensor value. Here, the blue light correction unit 91 includes an image analysis unit 92, a correction coefficient generation unit 93, and a multiplication unit 94.

  The image analysis unit 92, for example, averages the blue gradation value of each pixel for an image of a certain frame included in the input video signal, thereby obtaining a blue APL (Average Picture Level). calculate. Then, the image analysis unit 92 outputs information indicating the calculated blue APL to the correction coefficient generation unit 93.

For example, the correction coefficient generation unit 93 holds a correction table in which an APL and a correction coefficient are associated with each color mode. For example, the correction coefficient generation unit 93 refers to the correction table corresponding to the color mode included in the input control signal, and calculates the correction coefficient corresponding to the blue APL input from the image analysis unit 92 from the correction table. A correction coefficient is generated by reading. Then, the correction coefficient generation unit 93 outputs correction coefficient information indicating the generated correction coefficient to the multiplication unit 94.
The multiplying unit 94 generates the blue light photosensor value input from the blue light photosensor 36B and the blue light photosensor value at the timing when the image of the frame is displayed. By multiplying the correction coefficient, the corrected blue light optical sensor value is generated. The multiplying unit 94 outputs information indicating the generated blue light sensor value after correction to the duty determining unit 100.

  Next, the correction table held by the correction coefficient generation unit 83 and the correction table held by the correction coefficient generation unit 93 will be described. The correction coefficient generation unit 83 holds, for example, a correction table indicating the relationship between the correction coefficient and the APL in the case of the red light sensor value in FIG. Further, the correction coefficient generation unit 93 holds a correction table indicating the relationship between the correction coefficient and the APL in the case of a blue light sensor value in FIG.

  FIG. 4 is a diagram illustrating the relationship between the correction coefficient and the APL. The vertical axis in the figure is the correction coefficient, and the horizontal axis is the ratio [%] of APL to the maximum value of APL. In the figure, the relationship between the correction coefficient in the case of the sensor value for red light and APL, and the relationship between the correction coefficient in the case of the sensor value for blue light and APL are shown.

  The light reflected by the reflective liquid crystal panel 4R for red light is reflected again by the phosphor substrate 61. The value of the red light optical sensor 36R increases, for example, by the amount of recurring light when displaying black. Therefore, the sensor value of red light becomes larger as APL becomes smaller. Therefore, in order to correct the sensor value of the red light, the correction coefficient decreases as APL decreases. Thereby, the correction | amendment part 80 can approximate the sensor value of red light after correction | amendment to the intensity | strength of light when there is no recursive light.

  On the other hand, the light reflected by the reflective liquid crystal panel 4B for blue light returns to the illuminating device 51 for blue light but is hardly reflected by the diffusion plate 56. However, the blue light sensor value at the time of black display decreases due to the influence of the change in characteristics of the optical element such as the polarization conversion element 11 due to the light reflected by the blue reflective liquid crystal panel 4B. . In the example of FIG. 4, the correction coefficient is 1 when the ratio of APL to the maximum value of APL is 100%, and is 1 or more when the ratio of APL to the maximum value of APL is less than 100%. Thereby, the correction | amendment part 80 can approximate the sensor value of the blue light after correction | amendment to the intensity | strength of light when there is no recursive light.

FIG. 5 is a flowchart illustrating an example of a processing flow of the control unit 64 in the first embodiment. The control unit 64 performs the processes of steps S101 to S106 and steps S107 to S112 in parallel.
(Step S101) First, the image analysis unit 82 calculates a red APL from the video signal.
(Step S102) Next, the correction coefficient generation unit 83 calculates a correction coefficient for red light.
(Step S103) Next, the multiplying unit 84 multiplies the red light photosensor value by the red light correction coefficient to generate a corrected red light photosensor value.
(Step S104) Next, the duty determination unit 100 calculates the excitation duty value DutyY from the corrected red light optical sensor value.
(Step S105) Next, the PWM signal generation unit 67 generates a PWMY signal corresponding to the blinking of the excitation laser diode 62 using the excitation duty value DutyY.
(Step S106) Next, the excitation laser diode driver 68 drives the excitation laser diode 62 using the PWMY signal.

(Step S107) First, the image analysis unit 92 calculates a blue APL from the video signal.
(Step S108) Next, the correction coefficient generation unit 93 calculates a correction coefficient for blue light.
(Step S109) Next, the multiplier 94 multiplies the blue light photosensor value by the blue light correction coefficient to generate a corrected blue light photosensor value.
(Step S110) Next, the duty determination unit 100 calculates a blue duty value DutyB from the corrected blue light optical sensor value.
(Step S111) Next, the PWM signal generation unit 67 generates a PWMB signal corresponding to the blinking of the blue laser diode 59 using the blue duty value DutyB.
(Step S112) Next, the blue laser diode driver 69 drives the blue laser diode 59 using the PWMB signal. Above, the process of this flowchart is complete | finished.

  As described above, in the first embodiment, when the brightness of the entire screen is not maximum (for example, during black display), light returning to the light source side (hereinafter also referred to as recursive light) is taken into the optical sensor, so that the recursive light The light sensor value for red light is higher than when there is no light. Accordingly, there is a more specific problem that the red component in the image displayed by the projector becomes darker than the brightness of the desired red component.

  For the problem, in the first embodiment, the correction unit 80 corrects the light sensor value for red light according to APL (average pixel level), so that the brightness of the entire screen is not maximum ( For example, the light sensor value for red light that has risen when light returning to the light source side during black display is taken into the red light sensor 36R can be corrected. As a result, the projector 50 adjusts the light amount of the excitation laser diode 62 in accordance with the corrected red light optical sensor value, so that the red component and the green component in the displayed image are changed to the desired red component and green component, respectively. It can be displayed with the brightness of the component.

In addition, as another specific problem, when the brightness of the entire screen is not maximum (for example, when displaying black), the recursive light is influenced by the change in characteristics due to the temperature change of the optical element caused by the light returning to the light source side. The light sensor value for blue light is reduced compared to the case where there is no. Accordingly, there is a more specific problem that the blue component in the image displayed by the projector becomes brighter than the brightness of the desired blue component.
For the problem, in the first embodiment, the correction unit 80 corrects the light sensor value for blue light, so that the brightness of the entire screen is not maximum (for example, when displaying black), the light source side It is possible to correct the light sensor value for blue light which is reduced due to the influence of the change in characteristics due to the temperature change of the optical element caused by the light returning to the back. As a result, the projector 50 adjusts the amount of light of the blue laser diode 59 according to the corrected light sensor value for blue light, so that the blue component in the displayed image is displayed with the brightness of the desired blue component. Can do.

  In summary, in the projector 50 according to the first embodiment, the reflection type liquid crystal panels 4R, 4G, and 4B as the light modulators are light emitted from the light source 71 based on the image signal indicating the image to be projected. Modulate. The light detection unit 72 detects light brightness information related to the brightness of the light included in the optical path from the light source 71 to the light modulation unit. Then, the adjustment unit 70 corrects the light brightness information detected by the light detection unit 72 according to the image signal, and adjusts the output of the light source 71 with reference to the corrected light brightness information. Since the adjusting unit 70 adjusts the output of the light source 71 in accordance with the image signal, the projector 50 can display the brightness of an image to be displayed even if light reflection or absorption occurs when the light modulating unit modulates light. Can be brought close to the desired brightness.

  Furthermore, the adjustment unit 70 corrects the light brightness information detected by the light detection unit 72 according to the image signal. At that time, the adjustment unit 70 corrects the light brightness information detected by the light detection unit 72 according to the information related to the brightness of the image signal. More specifically, the light detection unit 72 detects light brightness information for each color of light, and the adjustment unit 70 provides information on the brightness for each color included in the image signal (for example, for each color of the image signal). The light brightness information of the corresponding light color detected by the light detection unit 72 is corrected according to the (average gradation value).

  In the first embodiment, the reflective liquid crystal panels 4R, 4G, and 4B may be transmissive liquid crystal panels. In particular, when a polarizing plate that reflects light to be blocked is used as the polarizing plate disposed on the emission side of the transmissive liquid crystal panel, the reflected light can be detected by the light detection unit 72. In the case of a transmissive liquid crystal panel, the liquid crystal driving unit 66 changes the transmittance of the transmissive liquid crystal panel using a signal input from the signal processing unit 65.

<Second Embodiment>
Next, the second embodiment will be described. The correction table in the first embodiment is greatly influenced by the table VRLUT (table VTLUT in the case of transmittance) that associates the gradation value of the image signal with the reflectance (or transmittance) of the display panel. When the user changes the color mode setting, it is necessary to change the table VRLUT. However, it is inefficient to prepare a correction table each time the table VRLUT is changed. Therefore, the projector 50b according to the second embodiment converts the APL into a reflectance using the table VRLUT, and generates a correction coefficient from the converted reflectance using the correction table, so that the color mode is set. A correction table can be shared.

  FIG. 6 is a schematic configuration diagram illustrating a configuration of the projector 50b according to the second embodiment. Elements common to those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted. In the configuration of the projector 50b in the second embodiment, the control unit 64 is changed to the control unit 64b with respect to the configuration of the projector 50 in the first embodiment.

  FIG. 7 is a schematic block diagram illustrating the configuration of the control unit 64b in the second embodiment. Elements common to those in FIG. 2 are denoted by the same reference numerals, and detailed description thereof is omitted. The configuration of the control unit 64b in the second embodiment is different from the configuration of the control unit 64 in the first embodiment in that the correction unit 80 of the signal processing unit 65 in the adjustment unit 70 is different from the signal processing unit 65b in the adjustment unit 70b. The correction unit 80b is changed.

FIG. 8 is a schematic block diagram illustrating the configuration of the correction unit 80b according to the second embodiment. The correction unit 80b includes a red light correction unit 81b and a blue light correction unit 91b. The red light correction unit 81 b includes an image analysis unit 82, a conversion unit 85, and a correction processing unit 86.
For example, the conversion unit 85 holds a table VRLUT in which APL and reflectance are associated with each other. The conversion unit 85 reads the reflectance corresponding to the red APL input from the image analysis unit 82 from the table VRLUT. Then, the conversion unit 85 outputs the reflectance information indicating the read reflectance to the correction coefficient generation unit 83b described later of the correction processing unit 86.

The correction processing unit 86 corrects the intensity of red light detected by the red light optical sensor 36R, for example, according to the reflectance obtained by the conversion by the conversion unit 85. Here, the correction processing unit 86 includes a correction coefficient generation unit 83 b and a multiplication unit 84. For example, the correction coefficient generation unit 83b holds a correction table in which the reflectance and the correction coefficient are associated with each other. The correction coefficient generation unit 83b reads a correction coefficient corresponding to the reflectance indicated by the reflectance information input from the conversion unit 85 from the correction table. Then, the correction coefficient generation unit 83 b outputs correction coefficient information indicating the read correction coefficient to the multiplication unit 84.
The multiplier 84 multiplies the red light optical sensor value by the correction coefficient read by the correction coefficient generation unit 83b to generate a corrected red light optical sensor value. The multiplier 84 outputs information indicating the corrected red light optical sensor value to the duty determining unit 100.

The blue light correction unit 91 b includes an image analysis unit 92, a conversion unit 95, and a correction processing unit 96.
The conversion unit 95 performs the same process as the conversion unit 85. Specifically, the conversion unit 95 holds, for example, a table VRLUT in which APL and reflectance are associated. The conversion unit 95 reads the reflectance corresponding to the red APL input from the image analysis unit 92 from the table VRLUT. Then, the conversion unit 95 outputs the reflectance information indicating the read reflectance to the correction coefficient generation unit 93b described later of the correction processing unit 96.

The correction processing unit 96 performs the same processing as the correction processing unit 86. Specifically, the correction processing unit 96 corrects the intensity of the blue light detected by the blue light optical sensor 36B, for example, according to the reflectance obtained by the conversion by the conversion unit 95. Here, the correction processing unit 96 includes a correction coefficient generation unit 93 b and a multiplication unit 94. For example, the correction coefficient generation unit 93b holds a correction table in which the reflectance and the correction coefficient are associated with each other. The correction coefficient generation unit 93b reads a correction coefficient corresponding to the reflectance indicated by the reflectance information input from the conversion unit 95 from the correction table. Then, the correction coefficient generation unit 93b outputs correction coefficient information indicating the read correction coefficient to the multiplication unit 94.
The multiplier 94 multiplies the blue light optical sensor value by the correction coefficient read by the correction coefficient generator 93b to generate a corrected blue light optical sensor value. The multiplication unit 94 outputs information indicating the corrected blue light optical sensor value to the duty determination unit 100.

  In the second embodiment, the reflective liquid crystal panels 4R, 4G, and 4B may be transmissive liquid crystal panels. In that case, the converters 85 and 95 may convert the APL into the transmittance using the table VTLUT and generate a correction coefficient from the converted transmittance using the correction table. In this case, it is assumed that APL and transmittance are associated with the table VTLUT. Further, it is assumed that the transmittance and the correction coefficient are associated with the correction table.

FIG. 9 is a flowchart illustrating an example of a processing flow of the control unit 64b in the second embodiment. The control unit 64b performs the processes of steps S201 to S207 and steps S208 to S214 in parallel.
The process of step S201 is the same as the process of step S101, and the process of step S204 to step S207 is the same as the process of step S103 to S106, so the description thereof is omitted.
(Step S202) Next, the conversion unit 85 generates the reflectance of the reflective liquid crystal panel 4R from the red APL.
(Step S203) Next, the correction coefficient generation unit 83b generates a correction coefficient from the reflectance of the reflective liquid crystal panel 4R.

The processing in step S208 is the same as the processing in step S107, and the processing in steps S211 to S214 is the same as the processing in steps S109 to S112.
(Step S209) Next, the conversion unit 95 generates the reflectance of the reflective liquid crystal panel 4B from the blue APL.
(Step S210) Next, the correction coefficient generator 93b generates a correction coefficient from the reflectance of the reflective liquid crystal panel 4B. Above, the process of this flowchart is complete | finished.

  As described above, in the second embodiment, the conversion units 85 and 95 convert information regarding the brightness of the color that is the target of the image signal into information indicating the reflection of the light modulation unit. Here, the information indicating reflection is information including reflectance and transmittance. The correction processing unit 86 corrects the red light intensity detected by the light detection unit 72 according to the information indicating the reflection obtained by the conversion by the conversion unit 85. In addition, the correction processing unit 96 corrects the blue light intensity detected by the light detection unit 72 according to the information indicating the reflection obtained by the conversion by the conversion unit 95. Thereby, according to the setting of the color mode, the conversion units 85 and 95 convert the information regarding the brightness of the color to be the target of the image signal into the information indicating the reflection of the light modulation unit. The light intensity can be corrected by the same process regardless of the color mode setting. As a result, the correction coefficient generation unit 83b can use a common correction table regardless of the color mode setting. Therefore, in addition to the effects of the first embodiment, the number of tables held by the correction coefficient generation unit 83b can be reduced, and the capacity of the memory held inside the correction coefficient generation unit 83b can be reduced.

  In each embodiment, the correction unit 80 uses APL, but is not limited thereto. The correction unit 80 may use the center level of the image signal or the mode value of the histogram.

  A program for executing each process of the control unit (64 or 64b) of each embodiment is recorded on a computer-readable recording medium, and the program recorded on the recording medium is read into a computer system and executed. By doing so, you may perform the various process mentioned above which concerns on a control part (64 or 64b).

  Here, the “computer system” may include an OS and hardware such as peripheral devices. Further, the “computer system” includes a homepage providing environment (or display environment) if the WWW system is used. “Computer-readable recording medium” means a flexible disk, a magneto-optical disk, a ROM, a writable non-volatile memory such as a flash memory, a portable medium such as a CD-ROM, a hard disk built in a computer system, etc. This is a storage device.

  Further, the “computer-readable recording medium” refers to a volatile memory (for example, DRAM (Dynamic) in a computer system that becomes a server or a client when a program is transmitted via a network such as the Internet or a communication line such as a telephone line. Random Access Memory)) that holds a program for a certain period of time is also included. The program may be transmitted from a computer system storing the program in a storage device or the like to another computer system via a transmission medium or by a transmission wave in the transmission medium. Here, the “transmission medium” for transmitting the program refers to a medium having a function of transmitting information, such as a network (communication network) such as the Internet or a communication line (communication line) such as a telephone line. The program may be for realizing a part of the functions described above. Furthermore, what can implement | achieve the function mentioned above in combination with the program already recorded on the computer system, what is called a difference file (difference program) may be sufficient.

  As mentioned above, although embodiment of this invention was explained in full detail with reference to drawings, a specific structure is not restricted to this embodiment. Each configuration in each embodiment, a combination thereof, and the like are examples, and the addition, omission, replacement, and other changes of the configuration can be made without departing from the spirit of the present invention. Further, the present invention is not limited by the embodiments, and is limited only by the scope of the claims.

3R, 3G, 3B Light guiding optical system 4R, 4G, 4B Reflective liquid crystal panel (light modulation unit)
DESCRIPTION OF SYMBOLS 5 Cross dichroic prism 6 Projection optical system 9 1st lens array 10 2nd lens array 11 Polarization conversion element 12 Superimposition lens 25 Dichroic mirror 26, 27, 28 Polarization beam splitter (polarization separation element)
32R, 32G, 32B Condensing lenses 34R, 34G, 34B Polarizing plate 36R Red light sensor 36G Green light sensor 36B Blue light sensor 37 First aperture (incident angle limiting member)
38 Second stop (incident angle limiting member)
50, 50b Projector 51 Illumination device for blue light 52 Illumination device for yellow light 53 Blue laser diode array 54 Parallelizing lens 55 Condensing lens 56 Diffuser plate 57 Pickup lens 58 Parallelizing lens 59 Blue laser diode 61 Phosphor substrate 62 For excitation Laser diode 64, 64b Control unit 65, 65b Signal processing unit 66 Liquid crystal drive unit 67 PWM signal generation unit 68 Laser diode drive unit for excitation 69 Blue laser diode drive unit 70, 70b Adjustment unit 71 Light source 72 Photodetection unit 80, 80b Correction Unit 81, 81b Red light correction unit 82, 92 Image analysis unit 83, 83b, 93, 93b Correction coefficient generation unit 84, 94 Multiplication unit 85, 95 Conversion unit 86, 96 Correction processing unit 91, 91b Blue light correction unit

Claims (8)

A light modulation unit that modulates light emitted from the light source based on an image signal indicating an image to be projected;
An adjusting unit that adjusts an output of the light source with reference to the image signal;
A projector comprising: A light detection unit that detects light brightness information related to the brightness of the light emitted from the light source;
The said adjustment part correct | amends the light brightness information which the said light detection part detected according to the said image signal, It refers to the light brightness information after correction | amendment, and adjusts the output of the said light source. The projector described.   The projector according to claim 2, wherein the light detection unit detects the light brightness information for light included in an optical path from the light source to the light modulation unit.   The projector according to claim 2 or 3, wherein the adjustment unit corrects the light brightness information detected by the light detection unit in accordance with information related to the brightness of the image signal. The light detection unit detects light brightness information for each color of light,
The projector according to claim 4, wherein the adjustment unit corrects light brightness information of a corresponding light color detected by the light detection unit in accordance with information on brightness of each color included in the image signal. . The adjusting unit is
A conversion unit that converts information on the brightness of one color included in the image signal into reflection information indicating reflection of the light modulation unit;
A correction processing unit that corrects the light brightness information of the one color detected by the light detection unit according to the reflection information obtained by the conversion by the conversion unit;
A projector according to claim 5.   The projector according to claim 5, wherein the information regarding the brightness for each color of the image signal is an average gradation value for each color of the image signal. A projector control method comprising a light modulation unit that modulates light emitted from a light source based on an image signal indicating an image to be projected,
A projector control method comprising a procedure of adjusting an output of the light source with reference to the image signal.

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