JP2015072387A - 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 light detection unit 72 that detects light brightness information on the brightness of light emitted from a light source 71, a temperature detection unit 301 that detects temperature information indicating temperature, and an adjustment unit 70d that corrects the light brightness information detected by the light detection unit 72 on the basis of the temperature information detected by the temperature detection unit 301 and adjust the output of the light source 71 on the basis of the light brightness information after the correction.

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

  Due to the deterioration of the light source, 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) One aspect of the present invention includes a light detection unit that detects light brightness information related to the brightness of light emitted from a light source, a temperature detection unit that detects temperature information indicating temperature, and the temperature detection unit. An adjustment unit that corrects light brightness information detected by the light detection unit based on the detected temperature information and adjusts the output of the light source based on the corrected light brightness information; is there. Thereby, the projector can improve the accuracy of adjustment of the output of the light source by correcting the light brightness information based on the temperature information, and the brightness of the image to be displayed can be brought close to the desired brightness. it can.

  (2) One embodiment of the present invention is the above-described projector, in which the light source includes a first light source and a second light source, and the light detection unit corresponds to the first light source. A first light detection unit; and a second light detection unit corresponding to the second light source, wherein the temperature detection unit includes a first temperature detection unit corresponding to the first light source, and the second light detection unit. A second temperature detection unit corresponding to the light source, and the adjustment unit detects the first temperature detected by the first light detection unit based on the first temperature information detected by the first temperature detection unit. 1 light brightness information is corrected, and the second light brightness information detected by the second light detection unit is corrected based on the second temperature information detected by the second temperature detection unit. The first light source is based on the corrected first light brightness information and the corrected second light brightness information. Adjusting one or both of the output of the output second light source. Thereby, the projector can improve the accuracy of adjustment of the output of the light source by correcting the light brightness information based on the temperature information for the first light source and the second light source, and can improve the accuracy of the image to be displayed. The brightness can be brought close to a desired brightness.

  (3) One embodiment of the present invention is the above-described projector, in which a first light modulation element corresponding to the first light source and a second light modulation element corresponding to the second light source are provided. The first light detection unit detects first light brightness information related to light brightness between the first light source and the first light modulation element, and the second light detection unit detects the second light brightness information about the light brightness between the first light source and the first light modulation element. The light detection unit detects second light brightness information related to light brightness between the second light source and the second light modulation element, and the first temperature detection unit detects the second light brightness information. A first light source ambient temperature detection unit for detecting first light source ambient temperature information indicating a temperature around one light source; and a first light modulation element ambient temperature indicating a temperature around the first light modulation element A first light modulation element ambient temperature detection unit for detecting information, wherein the second temperature detection unit detects a temperature around the second light source; A second light source ambient temperature detector for detecting second light source ambient temperature information, and a second light for detecting second light modulator ambient temperature information indicating a temperature around the second light modulator. A modulation element ambient temperature detector is included. Accordingly, the projector adjusts the output of the light source by correcting the light brightness information for the first light source and the second light source based on the temperature information around the light source and the temperature information around the light modulation element. Can be improved, and the brightness of the image to be displayed can be brought close to the desired brightness.

  (4) One embodiment of the present invention is the above-described projector, in which the first light source is a Y light source, the second light source is a B light source, and the first light. The detection unit and the first light modulation element ambient temperature detection unit are provided corresponding to one or both of R and G. Thus, the projector obtains light brightness information for the first light source (Y light source) and the second light source (B light source) based on the temperature information around the light source and the temperature information around the light modulation element. By correcting, the accuracy of adjusting the output of the light source can be improved, and the brightness of the image to be displayed can be brought close to the desired brightness.

  (5) According to one aspect of the present invention, the light detection unit detects light brightness information related to the brightness of light emitted from the light source, and the temperature detection unit detects temperature information indicating the temperature. The adjustment unit corrects the light brightness information detected by the light detection unit based on the temperature information detected by the temperature detection unit, and outputs the light source based on the corrected light brightness information. And a adjusting method. Thereby, the projector can improve the accuracy of adjustment of the output of the light source by correcting the light brightness information based on the temperature information, and the brightness of the image to be displayed can be brought close to the desired brightness. it can.

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 signal processing part in 1st Embodiment. It is an example of the graph which compared the relationship between the output of an optical sensor, and the attenuation factor of an optical sensor before and after correction | amendment by an adjustment part. 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 signal processing 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. It is a schematic block diagram which shows the structure of the projector in 3rd Embodiment. It is a schematic block diagram which shows the structure of the control part in 3rd Embodiment. It is a schematic block diagram which shows the structure of the signal processing part in 3rd Embodiment. It is a flowchart which shows an example of the flow of a process of the control part in 3rd Embodiment. It is a schematic block diagram which shows the structure of the projector in 4th Embodiment. It is a schematic block diagram which shows the structure of the control part in 4th Embodiment. It is an example of the graph showing the relationship between the brightness of the light source in 4th Embodiment, and a duty (Duty). It is a flowchart which shows an example of the flow of the process (light source initial confirmation process) of the control part in 4th Embodiment. It is a flowchart which shows an example of the flow of the process (light source degradation confirmation process) of the control part in 4th Embodiment.

<First Embodiment>
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. When a laser diode (hereinafter also referred to as LD) deteriorates, the wavelength of the light source changes. Specifically, for example, when the amount of light hitting the fluorescent plate changes due to degradation of the LD (for example, when the amount of light decreases), the wavelength of light emitted from the fluorescent plate changes. ) Here, the ratio of the amount of light detected by the optical sensor after the deterioration of the LD is defined as the ratio (for example, 70%) of the sensor detected light amount based on the amount of light detected by the optical sensor before the deterioration of the LD. Further, with the amount of light incident on the liquid crystal panel before the deterioration of the LD as a reference, the ratio of the amount of light incident on the liquid crystal panel after the deterioration of the LD is set as the actual light amount ratio (for example, 80%). In this case, for example, when the ratio of the actual light amount is 80%, the ratio of the light amount detected by the sensor may be 70% because the wavelength of the light source is shifted and the sensitivity of the optical sensor is lowered. Thus, due to the spectral sensitivity of the optical sensor, the ratio of the detected light quantity of the sensor differs from the actual ratio of the light quantity. Accordingly, there is a problem that the projector cannot display an image with a desired brightness. In contrast, the projector 50 according to the first embodiment corrects the sensor detected light amount, and adjusts the output of the light source with reference to the corrected sensor detected light amount. Thereby, the projector 50 can bring the brightness of the image to be displayed closer to a desired brightness.

  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.
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 4B for green 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 blue 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.

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.

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 FIGS. 6 and 10 described later. 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 FIGS. 6 and 10 to be described later. Any place where the amount of light can be detected may be used.

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.
In addition, the signal processing unit 65 performs processing for dimming control of the light source 71 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 quantity of the light source 71 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. The signal processing unit 65 receives a red light intensity signal from the red light optical sensor 36R. Then, for example, the signal processing unit 65 corrects the current value of the red light photosensor indicated by the red light intensity signal. The signal processing unit 65 determines an excitation duty value DutyY indicating the duty of light emission of the excitation laser diode 62 with reference to the corrected red light optical sensor value obtained by the correction. The signal processing unit 65 outputs information indicating the determined excitation duty value DutyY to the PWM signal generation unit 67.

  The signal processing unit 65 receives the blue light intensity signal from the blue light optical sensor 36B. Then, for example, the signal processing unit 65 corrects the current value of the blue light optical sensor indicated by the blue light intensity signal. The signal processing unit 65 determines a blue duty value DutyB indicating the light emission duty of the blue laser diode 59 with reference to the corrected blue light optical sensor value obtained by the correction. The signal processing unit 65 outputs information indicating the determined blue duty value DutyB to the PWM signal generation unit 67.

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 signal processing unit 65 in the first embodiment. The signal processing unit 65 corrects the red light optical sensor value and the blue light optical sensor value at a predetermined timing. Here, the signal processing unit 65 includes a wavelength change estimation unit 80, a red light multiplication unit 84, a duty determination unit 85, a polarization change estimation unit 90, and a blue light multiplication unit 94.

  The wavelength change estimation unit 80 estimates the wavelength change of the red light LR. Here, the wavelength change estimation unit 80 includes a red light optical sensor reference value storage unit 81, a red light attenuation ratio calculation unit 82, and a red light correction coefficient determination unit 83. The red light photosensor reference value storage unit 81 stores a red light photosensor reference value. The red light optical sensor reference value is, for example, the red light optical sensor value at the time of shipment of the projector 50.

The red light attenuation ratio calculation unit 82 reads the red light optical sensor reference value from the red light optical sensor reference value storage unit 81. The red light attenuation ratio calculation unit 82 calculates the red light attenuation ratio by dividing the current value of the red light optical sensor by the reference value of the red light optical sensor. Then, the red light attenuation ratio calculation unit 82 outputs information indicating the red light attenuation ratio to the red light correction coefficient determination unit 83.
The red light correction coefficient determination unit 83 determines a red light correction coefficient in accordance with the red light attenuation ratio. Specifically, for example, the red light correction coefficient determination unit 83 stores a table in which the red light attenuation ratio and the red light correction coefficient are associated with each other. In that case, the red light correction coefficient determination unit 83 reads the red light correction coefficient corresponding to the red light attenuation ratio indicated by the information input from the red light attenuation ratio calculation unit 82, for example, by reading the red light Determine the correction factor. Thereby, the red light correction coefficient corresponding to the red light attenuation ratio is determined. The red light correction coefficient determination unit 83 outputs information indicating the determined red light correction coefficient to the red light multiplication unit 84.

  The red light multiplication unit 84 multiplies the red light photosensor value after correction by multiplying the red light photosensor current value by the red light correction coefficient indicated by the information input from the red light correction coefficient determination unit 83. calculate. As a result, an error in the current value of the red light photosensor due to a change in the wavelength of the yellow light LY emitted from the yellow light illumination device 52 (FIG. 1) is corrected.

  As described above, when the red light optical sensor value decreases, the wavelength change estimation unit 80 reduces the amount of light incident on the phosphor substrate 61 and changes the wavelength of the light output from the phosphor substrate 61. Estimated. As a result, the wavelength change estimation unit 80 causes the red light (or G light) of the projected image to be generated due to the difference between the spectral sensitivity characteristic of the red light optical sensor 36R and the relative visibility function that is the spectral sensitivity characteristic of the human eye. , Y light) and a red light correction coefficient for correcting an error between the red light light sensor 36R and the output. This correction factor for red light is caused by the luminance value of the red light (or G light, Y light) of the projected image, which is caused by the wavelength characteristics of the optical element such as the polarization separation element, and the output of the red light optical sensor 36R. It is possible to correct it including the error. Then, the wavelength change estimation unit 80 can obtain the corrected red light photosensor value by multiplying the red light photosensor current value by the correction coefficient.

  The duty determination unit 85 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 this time, the duty determination unit 85 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 determination unit 85 determines the excitation duty value DutyY and the blue duty value DutyB so as to change the intensity of the laser diode with high light intensity in accordance with the laser diode with low light intensity, for example. The duty determination unit 85 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 85 can control the light emission amount of the excitation laser diode 62 and the light emission amount of the blue laser diode 59.

The blue duty value is set so that the duty determination unit 85 increases the light intensity of the blue laser diode 59 when the light output of the blue laser diode 59 is reduced with a margin for the light output of the blue laser diode 59. DutyB may be determined.
Further, the duty determination unit 85 may determine the excitation duty value DutyY and the blue duty value DutyB so as to change the intensity of the laser diode having a low light intensity in accordance with the laser diode having a high light intensity, for example.
In the present embodiment, as an example, when acquiring the optical sensor value for color balance correction of the light source 71, it is assumed that a predetermined sequence is applied, and dimming adapted to the video signal is performed. Control shall not be implemented.

The polarization change estimation unit 90 estimates the polarization change of the blue light LB. Here, the polarization change estimation unit 90 includes a blue light optical sensor reference value storage unit 91, a blue light attenuation ratio calculation unit 92, and a blue light correction coefficient determination unit 93.
The blue light optical sensor reference value storage unit 91 stores a blue light optical sensor reference value. The blue light optical sensor reference value is, for example, the blue light optical sensor value at the time of shipment of the projector 50.

  The blue light attenuation ratio calculation unit 92 reads the blue light optical sensor reference value from the blue light optical sensor reference value storage unit 91. The blue light attenuation ratio calculation unit 92 calculates the blue light attenuation ratio by dividing the current value of the blue light optical sensor by the reference value of the blue light optical sensor. Then, the blue light attenuation ratio calculation unit 92 outputs information indicating the blue light attenuation ratio to the blue light correction coefficient determination unit 93.

  The blue light correction coefficient determination unit 93 determines the blue light correction coefficient according to the blue light attenuation ratio indicated by the information input from the blue light attenuation ratio calculation unit 92. Specifically, for example, the blue light correction coefficient determination unit 93 stores a table in which a blue light attenuation ratio and a blue light correction coefficient are associated with each other. In that case, the blue light correction coefficient determination unit 93 reads the blue light correction coefficient corresponding to the blue light attenuation ratio indicated by the information input from the blue light attenuation ratio calculation unit 92, for example, to correct the blue light. Determine the coefficient. Thereby, the blue light correction coefficient corresponding to the blue light attenuation ratio is determined. The blue light correction coefficient determination unit 93 outputs information indicating the determined blue light correction coefficient to the blue light multiplication unit 94.

  The blue light multiplication unit 94 multiplies the blue light optical sensor value by the blue light correction coefficient indicated by the information input from the blue light correction coefficient determination unit 93 by the blue light optical sensor current value. calculate. Thereby, the error of the current value of the blue light photosensor due to the change in polarization of the blue light LB is corrected.

  Thus, when the blue light sensor value decreases, the polarization change estimation unit 90 estimates that the polarization state after polarization conversion has changed due to the temperature characteristics of the polarization conversion element 11 (FIG. 1). . Then, the polarization change estimation unit 90 determines a correction coefficient for correcting an error in which the current value of the blue light photosensor changes more than the change in the light emission amount of the blue laser diode 59. Then, the polarization change estimation unit 90 can obtain the corrected blue light photosensor value by multiplying the blue light photosensor current value by the determined correction coefficient.

  In this embodiment, since both the wavelength change estimation unit 80 and the polarization change estimation unit 90 correct the optical sensor value based on the attenuation rate of the optical sensor value, error factors of these optical sensors are stored in one table. And each correction value may be obtained using the one table. Moreover, in this embodiment, although the correction value was determined using the attenuation rate from a reference value as an example, you may determine a correction value using the absolute value of an optical sensor value. By the above-described correction, the projector 50 can associate the light output from the illumination device (for example, the blue light illumination device 51) corresponding to the optical sensor output with high accuracy.

  FIG. 4 is an example of a graph comparing the relationship between the output of the optical sensor and the attenuation rate of the optical sensor before and after correction by the adjustment unit 70 (FIG. 2). In the figure, the vertical axis represents the optical sensor output, and the horizontal axis represents the attenuation factor of the optical sensor. Here, the attenuation factor of the optical sensor is a value obtained by multiplying the value obtained by dividing the current value of the optical sensor output by the reference value of the optical sensor output by 100. In the example of the figure, before the adjustment unit 70 corrects the value of the optical sensor, a downwardly convex curve L41 is shown, whereas after the correction, a straight line L42 is shown. That is, after correction, the output of the optical sensor is linear with respect to the attenuation rate.

FIG. 5 is a flowchart illustrating an example of a processing flow of the control unit 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 red light attenuation ratio calculation unit 82 calculates the red light attenuation ratio by dividing the current value of the red light optical sensor by the reference value of the red light optical sensor.
(Step S102) Next, the red light correction coefficient determination unit 83 determines a red light correction coefficient in accordance with the red light attenuation ratio.
(Step S103) Next, the red light multiplication unit 84 multiplies the red light photosensor current value by the red light correction coefficient to generate a corrected red light photosensor value.
(Step S104) Next, the duty determination unit 85 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 blue light attenuation ratio calculation unit 92 calculates the blue light attenuation ratio by dividing the blue light optical sensor current value by the blue light optical sensor reference value.
(Step S108) Next, the blue light correction coefficient determination unit 93 determines a blue light correction coefficient according to the blue light attenuation ratio.
(Step S109) Next, the blue light multiplication unit 94 multiplies the blue light optical sensor value by the blue light correction coefficient to generate a corrected blue light optical sensor value.
(Step S110) Next, the duty determination unit 85 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, the red light optical sensor 36R can detect the light emission amount of the excitation laser diode 62, but cannot detect the chromaticity change. Therefore, when the wavelength of the excitation laser diode 62 changes, the optical sensor output change rate is obtained at a change rate different from the change rate of the light emission amount of the excitation laser diode 62 due to the influence of the spectral sensitivity characteristic of the optical sensor. . As a result, there has been a problem that an image cannot be displayed with a desired brightness.
On the other hand, in the first embodiment, the wavelength change estimation unit 80 (FIG. 3) calculates a red light correction coefficient that corrects an error in the optical sensor output change rate due to the wavelength change of the excitation laser diode 62. Then, the red light multiplication unit 84 corrects the red light photosensor current value by multiplying the red light photosensor current value by the calculated red light correction coefficient. As a result, the excitation duty value DutyY is determined according to the corrected red light optical sensor value, so that the excitation laser diode 62 is driven at a duty corresponding to the corrected red light optical sensor value. In this way, the adjustment unit 70 can bring the brightness of an image to be displayed closer to a desired brightness by adjusting the light amount of the excitation laser diode 62.

In addition, a change in the polarization state of the light due to the influence of the temperature characteristics of the optical element or the like results in an optical sensor output change rate different from the change rate of the light emission amount of the blue laser diode 59. As a result, there has been a problem that an image cannot be displayed with a desired brightness.
On the other hand, in the first embodiment, the polarization change estimation unit 90 calculates a blue light correction coefficient that corrects an error in the optical sensor output change rate due to the polarization change of the blue laser diode 59. Then, the blue light multiplier 94 corrects the blue light photosensor current value by multiplying the blue light photosensor current value by the calculated blue light correction coefficient. As a result, the blue duty value DutyB is determined according to the corrected blue light optical sensor value, so that the blue laser diode 59 is driven at a duty according to the corrected blue light optical sensor value. In this way, the adjusting unit 70 can bring the brightness of the image to be displayed closer to a desired brightness by adjusting the amount of light of the blue laser diode 59.

  From the above, in the first embodiment, the adjusting unit 70 estimates light state information indicating the light state (for example, wavelength and polarization), and outputs the light source 71 based on the estimated light state information. Adjust. The polarization beam splitter 26 separates the light incident from the excitation laser diode 62 into light of different polarizations. The red light optical sensor 36R included in the light detection unit 72 detects light brightness information related to the brightness of light different from the light projected on the screen among the light separated by the polarization beam splitter 26. The polarization beam splitter 28 separates the light incident from the blue laser diode 59 into light of different polarizations. Similarly, the blue light optical sensor 36 </ b> B included in the light detection unit 72 detects light brightness information regarding the brightness of light different from the light projected on the screen among the light separated by the polarization beam splitter 28. Thereby, since the light detection part 72 detects light brightness information about the light of the polarization which is not projected on a screen, the projector 50 can detect light brightness information, without reducing the light quantity of the light projected on a screen. . Further, the polarizing beam splitter 26 is provided in the projector 50 in order to transmit only the P-polarized light and project only the P-polarized light. Therefore, the light detection unit 72 is configured to detect S-polarized light that is reflected by the polarization beam splitter 26 and is not used for projection, so that the projector 50 has a new configuration only for detecting light brightness information. Light brightness information can be detected without adding.

The adjustment unit 70 corrects the light brightness information detected by the light detection unit 72 based on the light state information, and adjusts the output of the light source 71 with reference to the corrected light brightness information. The adjusting unit 70 estimates the wavelength change of the light with reference to the light brightness information detected by the light detecting unit 72, and adjusts the output of the light source 71 based on the estimated wavelength change of the light. Thereby, the adjustment unit 70 can bring the brightness of the image to be displayed closer to a desired brightness by adjusting the shift of the output of the light source due to the change in the wavelength of the light.
Further, the adjustment unit 70 estimates the change in the polarization state of the light with reference to the light brightness information detected by the light detection unit 72, and adjusts the output of the light source 71 based on the estimated change in the polarization state of the light. To do. Thus, the projector 50 can bring the brightness of the image to be displayed closer to a desired brightness by adjusting the deviation of the output of the light source due to the change in the polarization of light.

<Second Embodiment>
Next, the second embodiment will be described. The characteristics of the wavelength change of the light source 71 are different when the light emission duty value is controlled and when the output of the light source 71 is lowered. For example, by controlling the light emission duty value, the temperature of the phosphor substrate 61 changes, but the peak light amount (light density) does not change. When the output of the excitation laser diode 62 decreases, both the temperature of the phosphor substrate 61 and the peak light amount change. As a result, the appearance of the change in the wavelength of the light changes depending on whether the light emission duty value is controlled or when the output of the light source 71 decreases.

  Therefore, the projector 50b according to the second embodiment differs from the projector 50 according to the first embodiment in the following points. The projector 50b determines the first correction coefficient based on the light emission duty value of the excitation laser diode 62 (hereinafter also referred to as yellow light source emission duty). Then, the projector 50b obtains a light amount change ratio other than the light amount change due to the light emission duty value by (sensor current value / sensor reference value) / Duty ratio. Here, the duty ratio is 1/100 of the light emission duty value. For example, when the light emission duty value is 50%, it is 0.5. The projector 50b determines the second correction coefficient according to the light amount change ratio other than the light amount change due to the light emission duty value. The projector 50b corrects the optical sensor value by multiplying the optical sensor value by a value obtained by adding the first correction coefficient and the second correction coefficient. With such a configuration, the projector 50b can correct the optical sensor output with higher accuracy than in the first embodiment.

  Note that although it is divided by the duty ratio, this is applicable when the relationship between the duty ratio and the brightness can be regarded as linear. More precisely, it is preferable that the projector 50b obtains a brightness ratio corresponding to the duty ratio from a table representing the relationship between the duty ratio and the brightness ratio and normalizes the brightness ratio. Thereby, the optical sensor output can be corrected with higher accuracy.

  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 a configuration in which the signal processing unit 65 of the adjustment unit 70 is changed to the signal processing unit 65b of the adjustment unit 70b with respect to the configuration of the control unit 64 in the first embodiment. It has become.

  FIG. 8 is a schematic block diagram showing the configuration of the signal processing unit 65b in the second embodiment. Elements common to those in FIG. 3 are denoted by the same reference numerals, and detailed description thereof is omitted. Unlike the signal processing unit 65 of the first embodiment, the signal processing unit 65b corrects the light sensor value for red light and the light sensor value for blue light in real time as an example. Here, the signal processing unit 65b includes a wavelength change estimation unit 80b, a red light multiplication unit 84, a duty determination unit 85, a polarization change estimation unit 90b, a blue light wavelength change estimation unit 100, and a blue light addition unit. 102 and a blue light multiplier 94.

The wavelength change estimation unit 80b includes a red light optical sensor reference value storage unit 81, a red light attenuation ratio calculation unit 82b, a first correction coefficient determination unit 86, a second correction coefficient determination unit 87, and an addition for red light. Part 88.
The red light attenuation ratio calculation unit 82b calculates a red light amount change ratio other than the red light amount change due to the light emission duty value, for example, according to (red light light sensor current value / red light light sensor reference value) / Duty ratio. The red light attenuation ratio calculation unit 82 b outputs information indicating the calculated red light amount change ratio to the second correction coefficient determination unit 87.

  The first correction coefficient determination unit 86 determines a first correction coefficient according to the input yellow light source emission duty. The yellow light source emission duty is the duty of the excitation laser diode 62. The first correction coefficient has a substantially linear relationship with the yellow light source emission duty. This is because the cause of wavelength change is only temperature. The first correction coefficient determination unit 86 outputs information indicating the determined first correction coefficient to the red light addition unit 88.

  Subsequently, an example of specific processing of the first correction coefficient determination unit 86 will be described. The first correction coefficient determination unit 86 stores, for example, a table T1 in which the yellow light source emission duty and the first correction coefficient are associated with each other. Then, the first correction coefficient determination unit 86 determines the first correction coefficient by, for example, reading the first correction coefficient corresponding to the input yellow light source emission duty from the table T1.

  Here, the table T1 is obtained, for example, by evaluating an error between the current value of the red light photosensor and the screen luminance while actually changing the duty of the excitation laser diode 62. At this time, in order to correct the red light photosensor current value using a value obtained by adding the first correction coefficient and a second correction coefficient described later, the red light photosensor current value is calculated using the first correction coefficient. When the correction is not performed, the table T1 is created so that the first correction coefficient becomes zero.

  The second correction coefficient determination unit 87 determines the second correction coefficient according to the red light amount change rate indicated by the information input from the red light attenuation ratio calculation unit 82b. Here, the second correction coefficient has a quadratic function relationship with the current value of the red light photosensor. This is because there are two causes of wavelength change: temperature and light density. The second correction coefficient determination unit 87 outputs information indicating the determined second correction coefficient to the red light addition unit 88.

Subsequently, an example of specific processing of the second correction coefficient determination unit 87 will be described. The second correction coefficient determination unit 87 stores, for example, a table T2 in which the red light amount change ratio other than the red light amount change based on the light emission duty value is associated with the second correction coefficient. Then, the second correction coefficient determination unit 87 determines the second correction coefficient by, for example, reading the second correction coefficient corresponding to the input red light amount change rate from the table T2.
Here, the first correction coefficient is larger than the second correction coefficient. This is because the first correction coefficient has no effect of canceling the error of two factors.

  The red light addition unit 88 adds the first correction coefficient indicated by the information input from the first correction coefficient determination unit 86 and the second correction coefficient indicated by the information input from the second correction coefficient determination unit 87. The red light addition unit 88 outputs information indicating the addition correction coefficient obtained by the addition to the red light multiplication unit 84.

  The red light multiplying unit 84 multiplies the current value of the red light sensor by the addition correction coefficient indicated by the information input from the red light adding unit 88 and multiplies the value obtained by the multiplication, thereby correcting the red light light. The sensor value. As a result, the signal processing unit 65b can perform correction according to the yellow light source emission duty on the current value of the red light sensor and correction according to the red light amount change ratio other than the red light amount change due to the yellow light source emission duty. . Then, the red light multiplication unit 84 outputs information indicating the obtained corrected red light optical sensor value to the duty determination unit 85.

The polarization change estimation unit 90b estimates the polarization change of the blue light LB. Here, the polarization change estimation unit 90b includes a blue light optical sensor reference value storage unit 91, a blue light attenuation ratio calculation unit 92b, and a fourth correction coefficient determination unit 96.
The blue light attenuation ratio calculation unit 92b calculates a blue light amount change ratio other than a blue light amount change due to the light emission duty value, for example, according to (blue light light sensor current value / blue light light sensor reference value) / blue light source duty ratio. . Here, the blue light source duty ratio is a value obtained by dividing the duty value of the blue laser diode 59 (hereinafter also referred to as blue light source emission duty) by 100. The blue light attenuation ratio calculation unit 92 b outputs information indicating the calculated blue light amount change ratio to the fourth correction coefficient determination unit 96.

  The fourth correction coefficient determination unit 96 determines a fourth correction coefficient according to the blue light amount change rate indicated by the information input from the blue light attenuation ratio calculation unit 92b. Here, the fourth correction coefficient has a quadratic function relationship with the red light optical sensor value. This is because the polarization state change is dominant. The second correction coefficient determination unit 87 outputs information indicating the determined fourth correction coefficient to the blue light addition unit 102.

  An example of specific processing of the fourth correction coefficient determination unit 96 will be described. For example, it is assumed that the fourth correction coefficient determination unit 96 stores a table T4 in which the blue light amount change ratio other than the blue light amount change by the light emission duty value is associated with the fourth correction coefficient. Then, the fourth correction coefficient determination unit 96 determines the fourth correction coefficient by, for example, reading the fourth correction coefficient corresponding to the input blue light amount change rate from the table T4.

The blue light wavelength change estimation unit 100 estimates the wavelength change of the blue light LB based on the blue light source emission duty. The blue light wavelength change estimation unit 100 includes a third correction coefficient determination unit 101.
The third correction coefficient determination unit 101 calculates a third correction coefficient according to the blue light source emission duty. Here, the third correction coefficient has a quadratic function relationship with the blue light source emission duty. This is because two factors of wavelength change and polarization state change are combined. The third correction coefficient determination unit 101 outputs information indicating the calculated third correction coefficient to the blue light addition unit 102.
Here, the third correction coefficient is larger than the fourth correction coefficient. This is because the wavelength change due to temperature change is large during PWM dimming.

  An example of specific processing of the third correction coefficient determination unit 101 will be described. For example, the third correction coefficient determination unit 101 stores a table T3 in which the blue light source emission duty and the third correction coefficient are associated with each other. Then, the third correction coefficient determination unit 101 determines the third correction coefficient by, for example, reading the third correction coefficient corresponding to the input blue light amount change rate from the table T3.

  Here, the table T3 is obtained, for example, by evaluating an error between the blue light optical sensor value and the screen luminance while actually changing the duty of the blue laser diode 59. At this time, since correction is performed using a value obtained by adding a third correction coefficient and a fourth correction coefficient described later, the third correction coefficient is 0 when the light sensor value for blue light is not corrected using the third correction coefficient. The table T3 is created so that

The blue light addition unit 102 adds the third correction coefficient indicated by the information input from the third correction coefficient determination unit 101 and the fourth correction coefficient indicated by the information input from the fourth correction coefficient determination unit 96. The blue light addition unit 102 outputs the second addition correction coefficient obtained by the addition to the blue light multiplication unit 94.
The blue light multiplier 94 multiplies the current value of the blue light sensor by the second addition correction coefficient indicated by the information input from the blue light adder 102 and multiplies the value obtained by multiplying the blue light after correction. The light sensor value. Then, the blue light multiplication unit 94 outputs the obtained corrected blue light optical sensor value to the duty determination unit 85.

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.
(Step S201) First, the red light attenuation ratio calculation unit 82b calculates a red light amount change ratio other than the red light amount change by the light emission duty value.
(Step S202) Next, the first correction coefficient determination unit 86 determines the first correction coefficient in accordance with the yellow light source emission duty. In parallel with this, the second correction coefficient determination unit 87 determines the second correction coefficient according to the red light amount change rate.
(Step S203) Next, the red light adding unit 88 calculates the addition correction coefficient by adding the first correction coefficient and the second correction coefficient.
(Step S204) Next, the red light multiplication unit 84 calculates the corrected red light photosensor value by multiplying the red light photosensor current value by the addition correction coefficient.
Since the process of step S205-step S207 is the same as the process of step S104-S106, the description is abbreviate | omitted.

(Step S208) Next, the blue light attenuation ratio calculation unit 92b calculates a blue light amount change ratio other than the blue light amount change by the light emission duty value.
(Step S209) Next, the third correction coefficient determination unit 101 determines a third correction coefficient in accordance with the blue light source emission duty. In parallel with this, the fourth correction coefficient determination unit 96 determines the fourth correction coefficient according to the blue light quantity change rate.
(Step S210) Next, the blue light addition unit 102 adds the third correction coefficient and the fourth correction coefficient to calculate a second addition correction coefficient.
(Step S211) Next, the blue light multiplier 94 calculates the corrected blue light optical sensor value by multiplying the blue light optical sensor current value by the second addition correction coefficient.
Since the process of step S212-step S214 is the same as the process of step S110-S112, the description is abbreviate | omitted. Above, the process of this flowchart is complete | finished.

As described above, in the second embodiment, the signal processing unit 65b performs the correction according to the yellow light source emission duty and the correction according to the red light amount change ratio other than the red light amount change due to the yellow light source emission duty. Can be applied to the value. Similarly, the signal processing unit 65b can perform correction according to the blue light source emission duty and correction according to the blue light amount change ratio other than the blue light amount change due to the blue light source emission duty on the blue light photosensor current value. .
Accordingly, the projector 50b can correct the optical sensor output with higher accuracy than in the first embodiment. As a result, the brightness of the image to be displayed can be made closer to the desired brightness with higher accuracy than in the first embodiment. Further, the projector 50b can correct the light source light amount by using the red light photosensor current value or the blue light photosensor current value even during the control to change the light emission duty in accordance with the video.

<Third Embodiment>
Subsequently, a third embodiment will be described. The projector 50 c in the third embodiment includes a temperature sensor (temperature detection unit) 110. The projector 50c corrects the optical sensor output according to the change of the temperature sensor value from the reference value. By using the temperature sensor, the projector 50c can correct the color balance of the light source 71 including the environmental temperature change which is a temperature change other than the temperature change due to the deterioration of the output of the light source 71.

  FIG. 10 is a schematic configuration diagram illustrating a configuration of a projector 50c according to the third 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 50c in the third embodiment, the temperature sensor 110 is added to the configuration of the projector 50 in the first embodiment, and the control unit 64 is changed to the control unit 64c.

  As an example, it is assumed that the temperature sensor 110 is disposed in the vicinity of an exhaust port of an exhaust flow of a cooling fan (not shown). The temperature sensor may be disposed near the intake port. The temperature sensor 110 measures the ambient environmental temperature and outputs temperature information indicating the measured environmental temperature (hereinafter also referred to as a current temperature sensor value) to the control unit 64c.

  FIG. 11 is a schematic block diagram illustrating the configuration of the control unit 64c in the third 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 64c in the third embodiment is a configuration in which the signal processing unit 65 of the adjustment unit 70 is changed to the signal processing unit 65c of the adjustment unit 70c with respect to the configuration of the control unit 64 in the first embodiment. It has become.

  FIG. 12 is a schematic block diagram illustrating the configuration of the signal processing unit 65c in the third embodiment. Elements common to those in FIG. 3 are denoted by the same reference numerals, and detailed description thereof is omitted. Similar to the signal processing unit 65 of the first embodiment, the signal processing unit 65c corrects the red light optical sensor value and the blue light optical sensor value at a predetermined timing as an example. The configuration of the signal processing unit 65c in the third embodiment is different from the configuration of the signal processing unit 65 in the first embodiment in that the wavelength change estimation unit 80 is the wavelength change estimation unit 80c and the polarization change estimation unit 90 is the polarization. The change estimation unit 90c is changed.

The wavelength change estimation unit 80c includes a red light temperature sensor reference value storage unit 89, a first temperature change ratio calculation unit 82c, and a red light correction coefficient determination unit 83c.
The red light temperature sensor reference value storage unit 89 stores a red light temperature sensor reference value.
The first temperature change ratio calculation unit 82 c reads the red light temperature sensor reference value from the red light temperature sensor reference value storage unit 89. The first temperature change ratio calculation unit 82 c acquires temperature information from the temperature sensor 110. The first temperature change ratio calculation unit 82c calculates the value obtained by dividing the temperature sensor current value indicated by the temperature information by the red light temperature sensor reference value and dividing it as the first temperature change ratio. The first temperature change ratio calculation unit 82c outputs information indicating the calculated first temperature change ratio to the red light correction coefficient determination unit 83c.

  The red light correction coefficient determination unit 83c determines the red light correction coefficient according to the first temperature change ratio indicated by the information input from the first temperature change ratio calculation unit 82c. Specifically, for example, a table in which the first temperature change ratio and the red light correction coefficient are associated with each other is stored in advance in the red light correction coefficient determination unit 83c. Then, the red light correction coefficient determination unit 83c reads, from the table, the red light correction coefficient corresponding to the first temperature change ratio input from the first temperature change ratio calculation unit 82c, for example. To decide. Then, the red light correction coefficient determination unit 83 c outputs information indicating the determined red light correction coefficient to the red light multiplication unit 84.

The polarization change estimation unit 90c includes a blue light temperature sensor reference value storage unit 95, a second temperature change ratio calculation unit 92c, and a blue light correction coefficient determination unit 93c.
The blue light temperature sensor reference value storage unit 95 stores a blue light temperature sensor reference value.
The second temperature change ratio calculation unit 92 c reads the blue light temperature sensor reference value from the blue light temperature sensor reference value storage unit 95. The second temperature change ratio calculation unit 92 c acquires temperature information from the temperature sensor 110. The first temperature change ratio calculation unit 82c calculates a value obtained by dividing the temperature sensor current value indicated by the temperature information by the blue light temperature sensor reference value and dividing the value as the second temperature change ratio. The second temperature change ratio calculation unit 92c outputs information indicating the calculated second temperature change ratio to the blue light correction coefficient determination unit 93c.

  The blue light correction coefficient determination unit 93c determines the blue light correction coefficient according to the second temperature change ratio indicated by the information input from the second temperature change ratio calculation unit 92c. Specifically, for example, a table in which the second temperature change ratio and the blue light correction coefficient are associated with each other is stored in advance in the blue light correction coefficient determination unit 93c. Then, the blue light correction coefficient determination unit 93c reads, for example, the blue light correction coefficient corresponding to the second temperature change ratio input from the second temperature change ratio calculation unit 92c from the table, thereby correcting the blue light correction coefficient. To decide. Then, the blue light correction coefficient determination unit 93 c outputs information indicating the determined blue light correction coefficient to the blue light multiplication unit 94.

FIG. 13 is a flowchart illustrating an example of a processing flow of the control unit 64c in the third embodiment. The control unit 64 performs the processes of steps S301 to S306 and steps S307 to S312 in parallel.
(Step S301) First, the first temperature change ratio calculation unit 82c obtains the first temperature change ratio by dividing the current temperature sensor value by the temperature sensor reference value for red light.
(Step S302) Next, the red light correction coefficient determination unit 83c calculates a red light correction coefficient in accordance with the first temperature change ratio.
Since the processing from step S303 to step S306 is the same as the processing from step S103 to S106, the description thereof is omitted.

(Step S307) Next, the second temperature change ratio calculating unit 92c obtains the second temperature change ratio by dividing the temperature sensor current value by the red light temperature sensor reference value.
(Step S308) Next, the blue light correction coefficient determination unit 93c calculates a blue light correction coefficient in accordance with the second temperature change ratio.
Since the process of step S309-step S312 is the same as the process of step S109-S112, the description is abbreviate | omitted. Above, the process of this flowchart is complete | finished.

As described above, in the third embodiment, the signal processing unit 65c corrects the red light photosensor current value according to the temperature sensor current value. Similarly, the signal processing unit 65c corrects the blue light photosensor current value according to the temperature sensor current value. The signal processing unit 65c determines the excitation duty value DutyY and the blue duty value DutyB with reference to the corrected red light optical sensor value and the corrected blue light optical sensor value. Then, the adjustment unit 70c adjusts the output of the light source 71 with reference to the determined excitation duty value DutyY and blue duty value DutyB.
Thereby, the projector 50c can correct | amend the optical sensor output error by the wavelength shift of the light resulting from environmental temperature change. Since the adjustment unit 70c adjusts the output of the light source 71 in accordance with the corrected optical sensor output, the projector 50c brings the brightness of the image to be displayed closer to the desired brightness, as in the first embodiment. be able to.

  From the above, in the third embodiment, the projector 50c further includes a temperature detection unit that detects environmental temperature information indicating the environmental temperature. The adjusting unit 70c estimates the light state information with reference to the environmental temperature information detected by the temperature detecting unit, and adjusts the output of the light source 71 based on the estimated light state information. Thereby, since the projector 50 can estimate the light state information with reference to the temperature information, the error of the light brightness information due to the wavelength shift of the light caused by the temperature change can be corrected.

  Note that the projector of the first embodiment or the second embodiment may be configured to include the correction unit 73c in addition to the respective configurations. In that case, in the projector 50 according to the first embodiment, for example, the correction unit 73c is connected before and after the correction unit 73, and the correction unit 73c further corrects the red light sensor value and the blue light sensor value. Also good. In the projector 50b in the second embodiment, for example, the correction unit 73c is connected before and after the correction unit 73b, and the correction unit 73c further corrects the red light sensor value and the blue light sensor value. Good. That is, the adjustment unit (70 or 70b) estimates the light state information with reference to the light brightness information detected by the light detection unit and the environmental temperature information detected by the temperature sensor 110. Thereby, the optical sensor output error due to the wavelength shift of the light emitted from the light source 71 due to the environmental temperature change can be corrected while correcting the optical sensor output error due to the wavelength shift due to the light emission amount of the light source 71. Therefore, the optical sensor output can be corrected with higher accuracy than in the first embodiment or the second embodiment. As a result, it is possible to bring the brightness of the image to be displayed closer to the desired brightness with higher accuracy than in the first embodiment or the second embodiment.

  In the present embodiment, the temperature sensor 110 detects the environmental temperature, but the present invention is not limited to this. The projector 50c may include a first temperature sensor and a second temperature sensor. The first temperature sensor may detect the temperature around the phosphor substrate 61 for the excitation laser diode 62 (hereinafter also referred to as Y light source). This is because the amount of wavelength shift of light varies depending on the temperature of the phosphor substrate 61. For the blue laser diode 59 (hereinafter also referred to as B light source), the second temperature sensor may detect the temperature around the polarization conversion element 11. This is because the polarization state of light changes depending on the temperature of the polarization conversion element 11. In this case, the first temperature sensor outputs the current temperature value around the phosphor substrate 61 to the first temperature change ratio calculation unit 82c. The red light temperature sensor reference value storage unit 89 stores, for example, a reference value of the temperature around the phosphor substrate 61 in advance. The first temperature change ratio calculation unit 82c may calculate the correction coefficient for red light by dividing the current value of the temperature around the phosphor substrate 61 by the reference value of the temperature around the phosphor substrate 61. Further, the second temperature sensor outputs the current value around the polarization conversion element 11 to the second temperature change ratio calculation unit 92c. Further, in the blue light temperature sensor reference value storage unit 95, for example, a reference value of the temperature around the polarization conversion element 11 is stored in advance. The second temperature change ratio calculation unit 92c may calculate the blue light correction coefficient by dividing the current value of the temperature around the polarization conversion element 11 by the reference value of the temperature around the polarization conversion element 11.

The first temperature sensor is not limited to the temperature around the phosphor substrate 61 with respect to the Y light source, but is an optical element such as the excitation laser diode 62, the polarization conversion element 11, the polarization beam splitter 26, or the polarization beam splitter 27. The ambient temperature may be detected.
The second temperature sensor detects not only the temperature around the polarization conversion element 11 but also the temperature around the optical element such as the blue laser diode 59, the phosphor substrate 61, or the polarization beam splitter 28 for the B light source. May be.

<Fourth Embodiment>
Subsequently, a fourth embodiment will be described.
FIG. 14 is a schematic configuration diagram illustrating a configuration of a projector 50d according to the fourth embodiment. Elements common to those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted or omitted. The configuration of the projector 50d in the fourth embodiment is four temperature sensors (excitation LD temperature sensor 201, blue LD temperature sensor 202, red light for the configuration of the projector 50 in the first embodiment. A panel temperature sensor 211R and a blue light panel temperature sensor 211B) are added, and the control unit 64 is changed to a control unit 64d.

First, the projector 50d according to the present embodiment is an element common to FIG. 1, but an outline of the elements related to the present embodiment will be described.
In the projector 50d according to the present embodiment, the phosphor substrate 61 is excited by the light emitted from the excitation laser diode array 60 and converted into Y light. The Y light is converted into parallel light by the pickup lens 57 and the collimating lens 58, and after being uniformed by the multi-lens, the R light reflective liquid crystal panel 4R and the G light reflective liquid crystal panel 4G are illuminated. .
In addition, after the light emitted from the blue laser diode array 53 is made uniform by the diffusion plate 56, the reflective liquid crystal panel 4B for B light is illuminated in the same manner as the R optical path and the G optical path.
Then, the light after color synthesis is projected onto the screen SCR via the projection optical system 6 (for example, a projection lens).

Further, the light sensor for the Y light source (the light sensor for red light 36R and the light sensor for green light 36G) is a reflective liquid crystal panel for Y light (the reflective liquid crystal panel 4R for R light and the reflective type for G light). It is arranged near the liquid crystal panel 4G). An optical sensor for the B light source (blue light optical sensor 36B) is disposed in the vicinity of the reflective liquid crystal panel 4B for the B light. Each of the optical sensors 36R, 36G, 36B detects light separated by the polarization beam splitters 26, 27, 28 arranged in front of the respective reflective liquid crystal panels 4R, 4G, 4B. This light is light whose polarization direction has been rectified by the respective polarization conversion elements 11 disposed in front, but some of the components that cannot be rectified are detected by the respective optical sensors 36R, 36G, and 36B. It will be.
In addition, as arrangement | positioning of each optical sensor 36R, 36G, 36B, for example, the place which can detect the light quantity of Y light source and the light quantity of B light source should just be detected, and it is not limited to arrangement | positioning of this embodiment.

Next, regarding the projector 50d according to the present embodiment, temperature sensors (excitation LD temperature sensor 201, blue LD temperature sensor 202, red light panel temperature sensor 211R, and blue light use) which are elements different from those in FIG. The panel temperature sensor 211B) will be described.
In the present embodiment, temperature sensors for grasping the temperature state of the projector 50d and correcting the temperature (excitation LD temperature sensor 201, blue LD temperature sensor 202, red light panel temperature sensor 211R, blue light) Panel temperature sensor 211B), the periphery of the excitation laser diode 62 (excitation laser diode array 60), the periphery of the blue laser diode 59 (blue laser diode array 53), and the reflective liquid crystal panel 4R for R light. And a reflection type liquid crystal panel 4B for B light, respectively.

More specifically, in the present embodiment, the excitation LD temperature sensor 201 is attached to the excitation laser diode array 60, the blue LD temperature sensor 202 is attached to the blue laser diode array 53, and red light is used. The panel temperature sensor 211R is attached to the radiation fin 33R, and the blue light panel temperature sensor 211B is attached to the radiation fin 33B.
Here, the red light panel temperature sensor 211R and the blue light panel temperature sensor 211B may be arranged near the exhaust port of the exhaust flow of the cooling fan as an example, and as another example, the cooling fan It may be arranged near the inlet of the exhaust flow.
Each temperature sensor (excitation LD temperature sensor 201, blue LD temperature sensor 202, red light panel temperature sensor 211R, blue light panel temperature sensor 211B) is configured using a thermistor or the like.

  In the present embodiment, the temperature of the polarization beam splitters 26, 28, etc. is measured by temperature sensors (red light panel temperature sensor 211R, blue light panel temperature sensor 211B) mounted in the vicinity of the reflective liquid crystal panels 4R, 4B. It is possible to perform correction in consideration of characteristics. In addition, a temperature sensor (excitation LD temperature sensor 201, blue LD temperature sensor 202) mounted in the vicinity of the LD is used for correction in consideration of the temperature characteristics of the light source (excitation laser diode 62, blue laser diode 59). Is possible.

In this embodiment, a temperature sensor for R light (in this embodiment, a temperature sensor 211R for red light panel) is provided around the reflective liquid crystal panel 4R for R light as a temperature sensor for Y light. As another configuration example, instead of the temperature sensor for R light, a G light temperature sensor (for example, a green light panel temperature sensor 211G) is replaced with a G light reflective liquid crystal panel. A configuration provided around 4G may be used, or a configuration including both a temperature sensor for R light and a temperature sensor for G light may be used.
Here, in the configuration including both the temperature sensor for R light and the temperature sensor for G light, for example, instead of the detection result of the temperature sensor for R light in the present embodiment, the detection results of both of these temperature sensors. It is possible to use an average value of.
In addition, in ordinary projectors, each reflective liquid crystal panel and heat radiating fin are often provided with a temperature sensor for temperature monitoring. In this embodiment, such a temperature sensor can also be used. is there.

Here, various configurations may be used as the configuration of the projector 50d.
For example, the phosphor substrate 61 may be of a reflective type. The light source may be three LDs or LEDs of RGB. The light modulation unit (light modulation element) may be a transmissive liquid crystal panel or DMD. Further, the presence or absence of the diffusion plate 56 may be arbitrary. As described above, the detailed optical configuration is not limited to the configuration of the present embodiment.

FIG. 15 is a schematic block diagram illustrating the configuration of the control unit 64d according to the fourth embodiment. Elements common to those in FIG. 2 are denoted by the same reference numerals, and detailed description thereof is omitted or omitted. The configuration of the control unit 64d in the fourth embodiment is a configuration in which the signal processing unit 65 of the adjustment unit 70 is changed to the signal processing unit 65d of the adjustment unit 70d with respect to the configuration of the control unit 64 in the first embodiment. It has become.
Further, in FIG. 15, each temperature sensor (excitation LD temperature sensor 201, blue LD temperature sensor 202, red light panel temperature sensor 211R, blue light panel temperature sensor 211B) is included in the signal processing unit 65d. The connection is shown.
FIG. 15 shows a temperature detection unit 301 including temperature sensors (excitation LD temperature sensor 201, blue LD temperature sensor 202, red light panel temperature sensor 211R, blue light panel temperature sensor 211B). It is shown.

An overview of processing performed in the control unit 64d according to the present embodiment will be described.
In the present embodiment, except for the processing related to the temperature sensors (excitation LD temperature sensor 201, blue LD temperature sensor 202, red light panel temperature sensor 211R, blue light panel temperature sensor 211B), This is the same as in the case of the embodiment.

The signal processing unit 65d applies various image quality correction processes to the video signal, and the video is displayed on the screen SCR by the reflective liquid crystal panels 4R, 4G, and 4B via the RGB liquid crystal driving units 66R, 66G, and 66B. Is done.
The signal processing unit 65d also performs processing for light control of the light source. The amount of light from the light source is controlled based on, for example, brightness and color settings linked to user settings from the menu screen and color mode. Further, the light amount of the light source may be dimming controlled in accordance with the brightness (gradation value) of the video signal.

The signal processing unit 65d stores a table showing the relationship between the brightness of the light source and the duty (duty value of light emission), and by referring to the table, the duty value (excitation for realizing the set brightness) is stored. The duty value DutyY and the blue duty value DutyB) are obtained and output to the PWM signal generator 67.
The PWM signal generation unit 67 generates a PWM signal (PWMY signal, PWMB signal) corresponding to blinking of the light source from the duty value input from the signal processing unit 65d, and an LD drive unit (excitation laser diode drive unit 68). To the blue laser diode driving unit 69).

The LD drive unit (excitation laser diode drive unit 68, blue laser diode drive unit 69) is configured to output LD (excitation laser diode 62, blue color) according to the current value (PWMY signal, PWMB signal) specified by the signal processing unit 65d. The laser diode 59) is driven (constant current drive in this embodiment) to perform light emission control.
Further, on / off control of the LD (excitation laser diode 62, blue laser diode 59) is performed based on the waveform of the PWM signal (PWMY signal, PWMB signal).

Here, the light emission control of such a light source is based on the output (light sensor value) from each light sensor sent from each light sensor (red light light sensor 36R, blue light light sensor 36B) to the signal processing unit 65d. This is performed using the control value that has been subjected to the correction process.
In this embodiment, the output (temperature sensor) from each temperature sensor (excitation LD temperature sensor 201, blue LD temperature sensor 202, red light panel temperature sensor 211R, blue light panel temperature sensor 211B). Value) is sent to the signal processing unit 65d and used for correction processing for the optical sensor.

FIG. 16 is an example of a graph showing the relationship between the brightness of the light source and the duty in the fourth embodiment.
In the present embodiment, the signal processing unit 65d stores and refers to information represented by such a graph. This information is stored in advance as, for example, a lookup table (LUT: Look Up Table).
In the graph of FIG. 16, the horizontal axis represents the brightness of the light source (0% to 100% with respect to a predetermined reference value), and the vertical axis represents the duty (0% to 100% with respect to the predetermined reference value). Represents.
In the example of FIG. 16, the brightness and the duty of the light source are represented by a linear straight line 1001 having a one-to-one relationship.

FIG. 17 is a flowchart illustrating an example of the flow of processing (light source initial confirmation processing) of the control unit 64d according to the fourth embodiment. The light source initial confirmation process is performed, for example, at the time of shipping inspection of the projector 50d.
In the present embodiment, the light source initial confirmation process is performed in a state where the dimming control is not performed (the dimming off state).
(Step S401) First, the signal processing unit 65d controls the liquid crystal panel (in this embodiment, the reflective liquid crystal panels 4R, 4G, and 4B) to display black.
(Step S402) Next, the signal processing unit 65d sets the optical diaphragms (in the present embodiment, the first diaphragm 37 and the second diaphragm 38) arranged in the illumination system to a fully open state, and sets the illumination system to the illumination system. Set the arranged optical filter to the fully open state.

  (Step S403) Next, in the setting state of steps S401 to S402 described above, the signal processing unit 65d acquires the reference value of each temperature sensor. Specifically, the signal processing unit 65d sets the temperature detection value of the excitation LD temperature sensor 201 as its reference value YLS, sets the temperature detection value of the blue LD temperature sensor 202 as its reference value BLS, The temperature detection value of the red light panel temperature sensor 211R is set as the reference value RPA, and the temperature detection value of the blue light panel temperature sensor 211B is set as the reference value BPA. The signal processing unit 65d stores these reference values YLS, BLS, RPA, and BPA.

(Step S404) Next, in the setting state of steps S401 to S402 described above, the signal processing unit 65d acquires the reference value of each optical sensor. Specifically, the signal processing unit 65d sets the light detection value of the red light light sensor 36R as the reference value RSE, and sets the light detection value of the blue light light sensor 36B as the reference value BSE. The signal processing unit 65d stores these reference values RSE and BSE.
In this case, the signal processing unit 65d sets the current value of the excitation laser diode 62 to a predetermined constant value (for example, 2.0 A), and sets the current value of the blue laser diode 59 to a predetermined constant value. A value (for example, 1.2 A) is set, and a reference value for each optical sensor is acquired.
For example, intermittent lighting may be used as the lighting mode of the excitation laser diode 62 and the blue laser diode 59 when the reference value of each optical sensor is measured and acquired, or continuous lighting is used. May be used.

  Here, the setting states in steps S401 to S402 described above are examples, and other setting states may be used. For example, the liquid crystal panel may not display black, and the optical aperture and the optical filter may not be fully opened.

  As described above, the control unit 64d confirms the initial state of the light source using the optical sensor at the timing when various image adjustments are performed in the projector 50d as the light source initial confirmation process, and stores this as the reference state. . Thereafter, the control unit 64d controls the state of the light source so as to maintain this reference state. In addition, the control unit 64d determines factors that affect the amount of light received by the optical sensor (in this embodiment, display on the liquid crystal panel, optical diaphragm, and optical filter) in order to confirm the light emission state of the light source with high accuracy. Is set to a predetermined state.

FIG. 18 is a flowchart illustrating an example of a flow of processing (light source deterioration confirmation processing) of the control unit in the fourth embodiment. The light source deterioration confirmation process is performed to maintain the light source state measured at the time of shipping inspection. The light source deterioration confirmation process is, for example, an end sequence (for example, when the power is turned off) after a predetermined usage time (for example, 100 hours) has elapsed since the light source initial confirmation process or the previous light source deterioration confirmation process was performed. Sequence). As another configuration example, it may be performed in response to the user selecting the light source deterioration confirmation process from the menu screen and instructing the execution thereof. As another configuration example, the light source deterioration confirmation process may be performed at a timing different from that of the present embodiment, such as at the time of startup.
In the present embodiment, the light source deterioration confirmation process is performed in a state where the dimming control is not performed (the dimming off state).

(Step S451) First, the signal processor 65d controls the liquid crystal panel (in this embodiment, the reflective liquid crystal panels 4R, 4G, and 4B) to display black.
(Step S452) Next, the signal processing unit 65d sets the optical diaphragm (in the present embodiment, the first diaphragm 37 and the second diaphragm 38) disposed in the illumination system to a fully open state, and sets the illumination system to the illumination system. Set the arranged optical filter to the fully open state.

  (Step S453) Next, in the setting state of steps S451 to S452 described above, the signal processing unit 65d acquires the detection value of each temperature sensor. Specifically, the signal processing unit 65d acquires the temperature detection value YLS of the excitation LD temperature sensor 201, acquires the temperature detection value BLS of the blue LD temperature sensor 202, and uses the red light panel temperature sensor 211R. The temperature detection value RPA of the blue light panel temperature sensor 211B is acquired. The signal processing unit 65d stores these detection values YLS, BLS, RPA, and BPA.

  (Step S454) Next, in the setting state of Steps S451 to S452 described above, the signal processing unit 65d acquires detection values of the respective optical sensors. Specifically, the signal processing unit 65d acquires the light detection value RSE of the red light optical sensor 36R, and acquires the light detection value BSE of the blue light optical sensor 36B. In addition, the signal processing unit 65d stores these detection values RSE and BSE.

Here, the setting state of steps S451 to S452 described above is the same as the setting state of steps S401 to S402 in the light source initial confirmation process shown in FIG. As described above, in the light source initial check process and the light source deterioration check process, factors other than the light source deterioration that affect the amount of light received by the optical sensor (in this embodiment, the display of the liquid crystal panel, the optical aperture, and the optical filter) are eliminated. It is set to a predetermined state so that it can be performed.
In the process of step S454 described above, the signal processing unit 65d sets the current value of the excitation laser diode 62 and the current value of the blue laser diode 59 to predetermined constant values set in the light source initial confirmation process. . Note that the signal processing unit 65d determines the lighting mode of the excitation laser diode 62 and the blue laser diode 59 (for example, intermittent lighting or continuous lighting) when measuring and acquiring the reference value of each optical sensor. The same mode as that set in the light source initial check process is set.

  (Step S455) Next, the signal processing unit 65d derives and obtains the temperature correction coefficient (Y light) and the temperature correction coefficient (B light) using Expression (1) and Expression (2).

[Equation 1]
Temperature correction coefficient (Y light) = 1 + {Yα × (detection value YLS−reference value YLS)
+ Yβ × (detection value RPA−reference value RPA)}
(1)

[Equation 2]
Temperature correction coefficient (B light) = 1 + {Bα × (detection value BLS−reference value BLS)
+ Bβ × (detection value BPA−reference value BPA)}
(2)

Here, in Expression (1), the detection value YLS and the reference value YLS are the temperature detection value YLS in the light source deterioration confirmation process of the excitation LD temperature sensor 201 and the reference value YLS in the light source initial confirmation process, respectively. The detection value RPA and the reference value RPA are the temperature detection value RPA in the light source deterioration confirmation process of the red light panel temperature sensor 211R and the reference value YLS in the light source initial confirmation process, respectively.
In Expression (2), the detection value BLS and the reference value BLS are the temperature detection value BLS in the light source deterioration confirmation process of the blue LD temperature sensor 202 and the reference value BLS in the light source initial confirmation process, respectively. The value BPA and the reference value BPA are the temperature detection value BPA in the light source deterioration confirmation process of the blue light panel temperature sensor 211B and the reference value BPA in the light source initial confirmation process, respectively.
In addition, Yα and Yβ in the equation (1) and Bα and Bβ in the equation (2) are predetermined coefficients, respectively. For example, assuming that the temperature characteristics do not change, they are determined in advance evaluation. It is a constant value.

  (Step S456) Next, the signal processing unit 65d derives the corrected optical sensor value (Y light) and the corrected optical sensor value (B light) using Expressions (3) and (4). Ask.

[Equation 3]
Optical sensor value after correction (Y light) = temperature correction coefficient (Y light) × detection value RSE
(3)

[Equation 4]
Optical sensor value after correction (B light) = temperature correction coefficient (B light) × detection value BSE
(4)

Here, in Expression (3), the detection value RSE is the light detection value RSE in the light source deterioration confirmation process of the red light optical sensor 36R.
In Expression (4), the detection value BSE is the light detection value BSE in the light source deterioration confirmation process of the blue light optical sensor 36B.
As described above, the corrected optical sensor value related to the temperature is obtained by multiplying the acquired optical sensor value by the temperature correction coefficient. By calculating a temperature correction coefficient for the optical sensor value, it is possible to improve erroneous determination due to a light source deterioration state due to a change in the amount of received light depending on the light source temperature or the optical element temperature at the time of acquiring the optical sensor value.

  (Step S457) Next, the signal processing unit 65d derives and obtains the light source balance correction value (Y light) and the light source balance correction value (B light) using the equations (5) and (6). When only one of the light source balance correction value (Y light) and the light source balance correction value (B light) is used, only one of them may be derived and obtained.

[Equation 5]
Light source balance correction value (Y light)
= LSB_Y
× (Reference value RSE / Reference value BSE) / (Detection value RSE / Detection value BSE)
(5)

[Equation 6]
Light source balance correction value (B light)
= LSB_B
× (Detection value RSE / Detection value BSE) / (Reference value RSE / Reference value BSE)
(6)

Here, in Expression (5), the detection value RSE and the reference value RSE are the light detection value RSE in the light source deterioration confirmation process of the red light optical sensor 36R and the reference value RSE in the light source initial confirmation process, respectively. In the present embodiment, the corrected optical sensor value (Y light) obtained by correcting the temperature by Equation (3) is used as the detection value RSE.
In Expression (6), the detection value BSE and the reference value BSE are the light detection value BSE in the light source deterioration confirmation process of the blue light optical sensor 36B and the reference value BSE in the light source initial confirmation process, respectively. In the present embodiment, as the detection value BSE, a corrected optical sensor value (B light) obtained by correcting the temperature according to Expression (4) is used.
Further, LSB_Y in Expression (5) is the current brightness of the excitation laser diode 62. This brightness is represented by, for example, a ratio (% display) with respect to the maximum output.
In addition, LSB_B in Expression (6) is the current brightness of the blue laser diode 59. This brightness is represented by, for example, a ratio (% display) with respect to the maximum output.

In this manner, the control is performed so that the ratio between the sensor value of Y light (in this embodiment, the sensor value of R light is used) and the sensor value of B light is kept constant.
As an example, when (reference value RSE / reference value BSE) <(detection value RSE / detection value BSE), it is considered that the Y light is stronger or the B light is weaker than the reference. In this case, for example, the signal processing unit 65d controls the B light with the same intensity, and performs control to weaken the Y light according to the equation (5).
As another example, when (reference value RSE / reference value BSE)> (detection value RSE / detection value BSE), it is considered that the Y light is weaker or the B light is stronger than the reference. In this case, for example, the signal processing unit 65d controls the Y light with the intensity as it is, and performs control to weaken the B light according to the equation (6).
Here, when one light is strong or the other light is weak, any one of the control for weakening one light or the control for strengthening the other light may be used. Since the control for increasing the light amount of the light source against the deterioration of the light source may increase the thermal burden and deteriorate the reliability, the control is performed to reduce the light amount of the light source.

In this embodiment, when the light source balance correction value is obtained, the light source deterioration confirmation process ends.
When the light source deterioration confirmation process is executed in the end sequence, the signal processing unit 65d stores the result of the process and applies a new control amount (light source balance correction value) from the next startup of the projector 50d.
By performing such processing, grasping the deterioration state of the light source with high accuracy and performing correction control, it is possible to minimize the fluctuation of white balance due to the deterioration.

  Here, the order of the temperature sensor reference value acquisition process (step S403) and the optical sensor reference value acquisition process (step S404) in the light source initial confirmation process shown in FIG. 17 may be reversed. Similarly, the order of the temperature sensor value acquisition process (step S453) and the optical sensor value acquisition process (step S454) in the light source deterioration confirmation process shown in FIG. 18 may be reversed. However, in the light source initial confirmation process shown in FIG. 17 and the light source deterioration confirmation process shown in FIG. 18, the order of the temperature sensor value acquisition process and the optical sensor value acquisition process is preferably the same.

Further, in the light source initial confirmation process shown in FIG. 17 and the light source deterioration confirmation process shown in FIG. 18, when obtaining a light source balance correction value for a desired brightness of the light source, for example, the desired brightness (the same brightness) ) May be used to obtain the light source balance correction value, or the light source balance correction value may be obtained using different brightness, and the obtained light source balance correction value may be converted according to the desired brightness and used. May be used.
Further, in the light source initial confirmation process shown in FIG. 17 and the light source deterioration confirmation process shown in FIG. 18, for example, the light source balance correction value may be obtained without using the light source balance correction value, or the light source balance A configuration in which a light source balance correction value (further light source balance correction value) for the correction value is used in a state where the correction value is used may be used.

The signal processing unit 65d uses the light source balance correction value (Y light) or the light source balance correction value (B light) obtained in the light source deterioration confirmation process shown in FIG. To control.
Specifically, the signal processing unit 65d obtains the duty value corresponding to the light source balance correction value (Y light) by referring to the correspondence information between the brightness of the light source and the duty as shown in FIG. The excitation laser diode 62 is controlled via the excitation laser diode driving unit 68 using the duty value. Similarly, the signal processing unit 65d obtains a duty value corresponding to the light source balance correction value (B light) with reference to correspondence information between the brightness of the light source and the duty as shown in FIG. 16, and obtains the obtained duty value. Is used to control the blue laser diode 59 via the blue laser diode driver 69.
Various timings may be used as the timing for performing such control. For example, timing such as when the projector 50d is activated can be used.
The correspondence information between the brightness of the light source and the duty as shown in FIG. 16 may be prepared for each light source (in this embodiment, the excitation laser diode 62 and the blue laser diode 59), for example. Alternatively, it may be prepared in common for a plurality of light sources.

As an example, when video adaptive dimming is turned on with high brightness setting, the brightness for high brightness setting (for example, 100%) is multiplied by the brightness for adaptive dimming (for example, 70%), and the light source The result obtained by multiplying the balance correction value is set as the current brightness setting value.
As a specific example, when the light source balance correction value (Y light) = 100%, the light source balance correction value (B light) = 80%, and the Y light deteriorates, the Y light is 100% × 70% × 100%. = 70% brightness is controlled, and B light is controlled to be 100% × 70% × 80% = 56% brightness.

As described above, in the present embodiment, the detection result of the temperature sensor in the projector 50d that can detect the deterioration of the light source based on the detection result of the optical sensor and adjust the output of the light source according to the detected deterioration of the light source. The detection result of the optical sensor is corrected according to the above.
Specifically, in the projector 50d according to the present embodiment, a plurality of light sources (for example, an excitation laser diode 62 and a blue laser diode 59) and a plurality of light modulations that generate image light by modulating light from each light source. Elements (for example, reflective liquid crystal panels 4R, 4B) and a plurality of optical sensors (for example, red light optical sensor 36R, blue light optical sensor 36B) for detecting light between each light source and each light modulation element And a plurality of temperature sensors for detecting the temperature around each light source or each light modulation element (for example, temperature sensor for excitation LD 201, temperature sensor for blue LD 202, temperature sensor for red light panel 211R, for blue light) The temperature sensor for panel 211B) and the detection value of the light sensor are corrected based on the detection value of the temperature sensor, and the light source Check the state, and a signal processing unit 65d for controlling the light source (adjustment of the output of the light source) based on the deterioration state of the light source. Thereby, when determining whether or not the balance (ratio) between the output of the light source of Y light and the output of the light source of B light has changed due to deterioration or the like, the components that have changed due to deterioration due to temperature change are excluded, A component changed due to deterioration or the like other than a temperature change is detected, the brightness is corrected using the detection result, a duty value is obtained from the corrected brightness, and the light source is controlled.

  As described above, according to the projector 50d according to the present embodiment, the change in the amount of light received by the optical sensor caused by the temperature characteristics of the light source, the light modulation element, and the like is corrected, and the detected value of the light sensor is used. By detecting the deterioration state, for example, the deterioration state of the light source can be grasped in a short time and with high accuracy, and light source control that maintains the initial state can be realized. Such an effect is particularly effective after, for example, displaying a screen (for example, displaying a dark screen) where the temperature detected by the temperature sensor is low in a configuration that performs dimming.

In the conventional technology, for example, in order to detect the deterioration state of the light source by the optical sensor, it is necessary to separately control the instantaneous light emission amount change due to the temperature characteristics of the light source or the optical element interposed therebetween. . In addition, in the conventional technology, when acquiring the optical sensor value when the drive current of the light source is controlled, the difference in the amount of light received between the condition where the light source is controlled continuously and the condition where the temperature is stable after control is considered. There was a need to do. In the prior art, due to these causes, there has been a problem that the deterioration state of the light source cannot be accurately grasped.
On the other hand, in this embodiment, such a problem can be solved.

Here, each temperature sensor may be arranged in various places.
As a specific example, as a temperature sensor for the excitation laser diode 62 (in this embodiment, an excitation LD temperature sensor 201), the phosphor substrate 61 or its periphery, the polarization conversion element 11 or its periphery, a polarization beam splitter, or the like. 26 or its periphery, the polarization beam splitter 27, or its periphery.
The blue LD temperature sensor 202 may be disposed on the phosphor substrate 61 or its periphery, the polarization conversion element 11 or its periphery, the polarization beam splitter 28 or its periphery, or the like.
In the present embodiment, the temperature sensor is used to detect the temperature related to each of the light source and the light modulation element and the temperature correction is performed. However, as another configuration example, the temperature related to only the light source is detected using the temperature sensor. Alternatively, a configuration for performing temperature correction or a configuration for performing temperature correction by detecting a temperature related to only the light modulation element by a temperature sensor may be used.

The structural example which concerns on this embodiment is shown.
As an example of the configuration, the projector 50d according to the present embodiment detects light brightness information (in this embodiment, a light detection value) related to the brightness of light emitted from the light source (in this embodiment, the light source 71). A light detection unit (in this embodiment, a light detection unit 72), a temperature detection unit (in this embodiment, a temperature detection unit 301) that detects temperature information indicating temperature, and temperature information detected by the temperature detection unit The light brightness information detected by the light detection unit is corrected based on the light brightness information, and the output of the light source is adjusted based on the corrected light brightness information (in this embodiment, the adjustment unit 70d). And using formula (1) to formula (6).

  As an example of the configuration, in the projector 50d according to the present embodiment, the light source includes a first light source (excitation laser diode 62 in this embodiment) and a second light source (in this embodiment, a blue laser diode 59). The light detection unit includes a first light detection unit corresponding to the first light source (in this embodiment, a red light photosensor 36R, or as another configuration example, a green light photosensor). 36G) and a second light detection unit (in this embodiment, a blue light photosensor 36B) corresponding to the second light source, and the temperature detection unit includes a first light source corresponding to the first light source. Corresponding to the second light source and the temperature sensor for the excitation LD (in this embodiment, the temperature sensor for excitation LD 201, the temperature sensor for red light 211R or another example of the temperature sensor for green light). Do 2 temperature detection units (in this embodiment, a blue LD temperature sensor 202 and a blue light panel temperature sensor 211B), and the adjustment unit detects the first temperature detected by the first temperature detection unit. The first light brightness information detected by the first light detection unit is corrected based on temperature information, and the second temperature information detected by the second temperature detection unit is used to correct the second light information. The second light brightness information detected by the light detection unit is corrected, and the first light source is based on the corrected first light brightness information and the corrected second light brightness information. And / or the output of the second light source.

  As one configuration example, in the projector 50d according to the present embodiment, the first light modulation element corresponding to the first light source (in this embodiment, the reflective liquid crystal panel 4R for R light, or another configuration example). A reflective liquid crystal panel 4G for G light, and a second light modulation element corresponding to the second light source (in this embodiment, a reflective liquid crystal panel 4B for B light), The first light detection unit detects first light brightness information related to light brightness between the first light source and the first light modulation element, and the second light detection unit , Detecting second light brightness information related to light brightness between the second light source and the second light modulation element, and the first temperature detection unit is arranged around the first light source. A first light source ambient temperature detector that detects first light source ambient temperature information indicating the temperature of the light source (in this embodiment, excitation LD temperature sensor 201) and a first light modulation element ambient temperature detection unit (in the present embodiment, for detecting first light modulation element ambient temperature information indicating the temperature around the first light modulation element) A red light panel temperature sensor 211R or, as another configuration example, a green light panel temperature sensor), and the second temperature detection unit includes a second light temperature around the second light source. A second light source ambient temperature detecting section (in this embodiment, a blue LD temperature sensor 202) for detecting light source ambient temperature information, and a second light modulator that indicates the temperature around the second light modulator A second light modulation element ambient temperature detection unit (in this embodiment, a blue light panel temperature sensor 211B) that detects ambient temperature information is included.

  As a configuration example, in the projector 50d according to the present embodiment, the first light source is a Y light source, the second light source is a B light source, the first light detection unit, and the first light source. One light modulation element ambient temperature detector is provided corresponding to one or both of R and G.

  As an example of the configuration, in the control method of the projector 50d according to the present embodiment, the light detection unit detects the light brightness information related to the brightness of the light emitted from the light source, and the temperature detection unit indicates the temperature. The procedure for detecting the temperature information and the adjustment unit correct the light brightness information detected by the light detection unit based on the temperature information detected by the temperature detection unit, and the corrected light brightness information Adjusting the output of the light source based on the method.

  A program for executing each process of the control unit (64, 64b, 64c or 64d) of each embodiment is recorded on a computer-readable recording medium, and the program recorded on the recording medium is stored in a computer system. The various processes described above related to the control unit (64, 64b, 64c, or 64d) may be performed by reading and executing.

  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.

<Configuration example>
(1) One aspect of the present invention is a projector including an adjustment unit that estimates light state information indicating a state of light emitted from a light source and adjusts an output of the light source based on the estimated light state information. is there. As a result, even if the characteristics of the light emitted from the light source change due to the deterioration of the light source, the projector adjusts the output of the light source based on the light state information, so that the brightness of the image to be displayed is desired. Can be close to brightness.

  (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: Based on the light state information, 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. Accordingly, the projector corrects the error of the light brightness information detected by the light detection unit, and adjusts the output of the light source with reference to the corrected light brightness information, thereby adjusting the brightness of the image to be displayed to a desired value. Can be close to brightness.

  (3) Moreover, 1 aspect of this invention is the above-mentioned projector, Comprising: The said adjustment part estimates the said light state information with reference to the light brightness information which the said light detection part detected. Accordingly, the projector estimates the light state information with reference to the light brightness information, corrects the light brightness information detected by the light detection unit based on the estimated light state information, and corrects the corrected light brightness information. The output of the light source can be adjusted with reference to the information.

  (4) One embodiment of the present invention is the above-described projector, wherein the adjustment unit estimates a wavelength change of the light with reference to light brightness information detected by the light detection unit, and The output of the light source is adjusted based on the estimated wavelength change of the light. Accordingly, the projector can adjust the brightness of the output of the light source due to the change in the wavelength of light to bring the brightness of the image to be displayed closer to the desired brightness.

  (5) One embodiment of the present invention is the above-described projector, wherein the adjustment unit estimates a change in a polarization state of the light with reference to light brightness information detected by the light detection unit. The output of the light source is adjusted based on the estimated change in the polarization state of the light. Thus, the projector can adjust the brightness of the output of the light source due to the change in the polarization of light to bring the brightness of the image to be displayed closer to the desired brightness.

  (6) One embodiment of the present invention is the above-described projector, in which the light detection unit detects light brightness information related to light brightness different from light projected onto the screen. Thereby, the projector corrects the light brightness information related to the brightness of the light different from the light projected on the screen based on the light state information, and adjusts the output of the light source with reference to the corrected light brightness information. Can do. Thereby, the brightness of the image to be displayed can be brought close to the desired brightness.

  (7) One embodiment of the present invention is the above-described projector, further including a polarization separation element that separates light incident from the light source into light of different polarizations, and the light detection unit includes the polarization separation element. Among the separated lights, light brightness information relating to the brightness of light different from the light projected on the screen is detected. As a result, the projector detects the light brightness information for the polarized light that is not projected onto the screen, so that the light brightness information can be detected without reducing the amount of light projected onto the screen.

  (8) One embodiment of the present invention is the above-described projector, further including a temperature detection unit that detects temperature information indicating temperature, and the adjustment unit refers to the temperature information detected by the temperature detection unit. Then, the light state information is estimated, and the output of the light source is adjusted based on the estimated light state information. Accordingly, the projector can estimate the light state information with reference to the temperature information, and thus can correct the error in the light brightness information due to the wavelength shift of the light caused by the temperature change.

  (9) One embodiment of the present invention further includes a temperature detection unit that detects temperature information indicating temperature, and the adjustment unit detects light brightness information detected by the light detection unit and the temperature detection unit. The light state information is estimated with reference to the temperature information. Thereby, since the projector estimates the light state information with reference to both the light brightness information and the temperature information detected by the temperature detection unit, the accuracy of the light state information can be improved. Thereby, the brightness of the image to be displayed can be made closer to the desired brightness.

(10) Further, according to one aspect of the present invention, the adjustment unit estimates light state information indicating a state of light emitted from the light source, and adjusts the output of the light source based on the estimated light state information. A projector control method having a procedure. Thereby, even if the characteristics of the light emitted from the light source change due to the deterioration of the light source, the adjustment unit adjusts the output of the light source based on the light state information, thereby adjusting the brightness of the displayed image to a desired value. Can be close to brightness.
<End of configuration example>

  3R, 3G, 3B Light guiding optical system 4R, 4G, 4B Reflective liquid crystal panel (light modulation unit) 5 Cross dichroic prism 6 Projecting optical system 9 First lens array 10 Second lens array 11 Polarization conversion element 12 Superimposing lens 13 First 1 small lens 14 second small lens 25 dichroic mirrors 26, 27, 28 Polarizing beam splitters (polarization separation elements) 32R, 32G, 32B Condensing lenses 33R, 33G, 33B Radiation fins 34R, 34G, 34B Polarizing plate 36R For red light Light sensor 36G Light sensor for green light 36B Light sensor for blue light 37 First aperture (incident angle limiting member) 38 Second aperture (incident angle limiting member) 50, 50b, 50c, 50d Projector 51 Blue light illumination device 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 60 Excitation laser diode array 61 Phosphor substrate 62 Excitation laser diodes 64, 64b, 64c, 64d Control unit 65, 65b, 65c Signal processing unit 66R, 66G, 66B Liquid crystal drive unit 67 PWM signal generation unit 68 Excitation laser diode drive unit 69 Blue laser diode drive unit 70, 70b, 70c, 70d Adjustment unit 71 Light source 72 Photodetection unit 73 73b, 73c Correction unit 80, 80b, 80c Wavelength change estimation unit 81 Red light photosensor reference value storage unit 82, 82b Red light attenuation ratio calculation unit 82c First temperature change ratio calculation unit 83, 83 c Red light correction coefficient determination unit 84 Red light multiplication unit 85 Duty determination unit 86 First correction coefficient determination unit 87 Second correction coefficient determination unit 88 Red light addition unit 89 Red light temperature sensor reference value storage unit 90, 90b, 90c Polarization change estimation unit 91 Blue light sensor reference value storage unit 92, 92b Blue light attenuation ratio calculation unit 92c Second temperature change ratio calculation unit 93, 93c Blue light correction coefficient determination unit 94 Blue light multiplication unit 95 Blue light temperature sensor reference value storage unit 96 Fourth correction coefficient determination unit 100 Blue light wavelength change estimation unit 101 Third correction coefficient determination unit 102 Blue light addition unit 110 Temperature sensor (temperature detection unit) 201 For excitation LD Temperature sensor 202 Blue LD temperature sensor 211R Red light panel temperature sensor 211B Blue light Temperature sensor 301 temperature detector panel

Claims (5)

A light detection unit that detects light brightness information related to the brightness of light emitted from the light source;
A temperature detector for detecting temperature information indicating the temperature;
An adjustment unit that corrects light brightness information detected by the light detection unit based on temperature information detected by the temperature detection unit, and adjusts the output of the light source based on the corrected light brightness information; ,
A projector comprising: The light source includes a first light source and a second light source,
The light detection unit includes a first light detection unit corresponding to the first light source and a second light detection unit corresponding to the second light source,
The temperature detection unit includes a first temperature detection unit corresponding to the first light source, and a second temperature detection unit corresponding to the second light source,
The adjustment unit corrects the first light brightness information detected by the first light detection unit based on the first temperature information detected by the first temperature detection unit, and the second light detection unit detects the second light brightness information detected by the first light detection unit. Based on the second temperature information detected by the temperature detection unit, the second light brightness information detected by the second light detection unit is corrected, and the corrected first light brightness information and correction are performed. Adjusting one or both of the output of the first light source and the output of the second light source based on the second light brightness information later;
The projector according to claim 1. A first light modulation element corresponding to the first light source;
A second light modulation element corresponding to the second light source,
The first light detection unit detects first light brightness information related to light brightness between the first light source and the first light modulation element;
The second light detection unit detects second light brightness information related to light brightness between the second light source and the second light modulation element,
The first temperature detection unit includes a first light source ambient temperature detection unit that detects first light source ambient temperature information indicating a temperature around the first light source, and a periphery of the first light modulation element. A first light modulation element ambient temperature detection unit for detecting first light modulation element ambient temperature information indicating the temperature;
The second temperature detector includes a second light source ambient temperature detector that detects second light source ambient temperature information indicating a temperature around the second light source, and a periphery of the second light modulation element. A second light modulation element ambient temperature detection unit for detecting second light modulation element ambient temperature information indicating the temperature;
The projector according to claim 2. The first light source is a Y light source;
The second light source is a B light source,
The first light detection unit and the first light modulation element ambient temperature detection unit are provided corresponding to one or both of R and G.
The projector according to claim 3. A procedure for the light detection unit to detect light brightness information related to the brightness of light emitted from the light source;
The temperature detection unit detects the temperature information indicating the temperature,
The adjustment unit corrects the light brightness information detected by the light detection unit based on the temperature information detected by the temperature detection unit, and adjusts the output of the light source based on the corrected light brightness information And the steps to
Control method for a projector having

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