JP6286825B2 - Projector and control method thereof - Google Patents

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, the characteristics (for example, wavelength and polarization) of the light emitted from the light source change, which causes a problem that the brightness of the image displayed by the projector differs 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 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) Moreover, one aspect of the present invention is the above-described projector, further including a temperature detection unit that detects temperature information indicating an environmental temperature, and the adjustment unit uses the temperature information detected by the temperature detection unit. With reference, 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.
In one embodiment of the present invention, first light is emitted to a phosphor substrate that emits light according to incident light, and second light that is light having a wavelength of a predetermined wavelength or more is emitted from the phosphor substrate. A second light source, a second light detector for detecting second brightness information indicating the second brightness that is the brightness of the second light, and a second reference brightness that is the second brightness serving as a reference. A ratio of the second brightness indicated by the second brightness information detected by the second light detection unit and a first correction coefficient for correcting the second brightness detected by the second light detection unit; The first correction coefficient corresponding to the second brightness indicated by the second brightness information detected by the second light detection unit is determined based on the first information associated with The second brightness is corrected based on one correction coefficient, and the first light is corrected based on the corrected second brightness. And a regulating portion for regulating an output, said first correction coefficient is a coefficient for correcting the change in the detection result of said second optical detecting portion due to a change in wavelength of the first light, a projector.
One embodiment of the present invention is a projector, wherein the second light detection unit detects the second brightness information related to the brightness of the second light different from the second light projected onto a screen. .
In one embodiment of the present invention, the projector further includes a temperature detection unit that detects temperature information indicating temperature, and the adjustment unit is configured to detect the first light based on the temperature information detected by the temperature detection unit. Adjust the output of.
In one embodiment of the present invention, the projector further includes a temperature detection unit that detects temperature information indicating temperature, and the adjustment unit includes the second brightness information detected by the second light detection unit. The wavelength of the second light is estimated with reference to the temperature information detected by the temperature detection unit, and the output of the first light is adjusted based on the estimated wavelength.
In one embodiment of the present invention, third light is emitted to a polarization conversion element that emits incident light as light having a predetermined polarization state, and fourth light that is light in the polarization state is emitted from the polarization conversion element. A fourth light source to be detected, a fourth light detection unit that detects fourth brightness information indicating the fourth brightness that is the brightness of the fourth light, and a fourth reference brightness that is the reference fourth brightness. And the fourth brightness indicated by the fourth brightness information detected by the fourth light detection unit, and a second correction coefficient for correcting the fourth brightness detected by the fourth light detection unit. The second correction coefficient corresponding to the fourth brightness indicated by the fourth brightness information detected by the fourth light detection unit is determined based on the second information associated with The fourth brightness is corrected based on the second correction coefficient, and based on the corrected fourth brightness An adjustment unit that adjusts the output of the third light, and the second correction coefficient is a coefficient that corrects a change in a detection result of the fourth light detection unit due to a change in polarization characteristics of the polarization conversion element. Is a projector.
One embodiment of the present invention is a projector, wherein the fourth light detection unit detects the fourth brightness information related to the brightness of the fourth light different from the fourth light projected onto a screen. .
Another embodiment of the present invention is a projector, further comprising a polarization separating element you separate the fourth light of the incident fourth light different polarization from the fourth light source, the fourth light detection unit, out of the fourth light the polarization separation element are separated, and detects the fourth brightness information on the brightness of different said fourth light and the fourth light projected on the screen.
In one embodiment of the present invention, the projector further includes a temperature detection unit that detects temperature information indicating temperature, and the adjustment unit is configured to detect the third light based on the temperature information detected by the temperature detection unit. Adjust the output of.
In one embodiment of the present invention, the projector further includes a temperature detection unit that detects temperature information indicating temperature, and the adjustment unit includes the fourth brightness information detected by the fourth light detection unit. The polarization state of the fourth light is estimated with reference to the temperature information detected by the temperature detection unit, and the output of the third light is adjusted based on the estimated polarization state.
According to another aspect of the present invention, the first light is emitted from the second light source to the phosphor substrate that emits light according to the incident light, and the light having a wavelength equal to or greater than a predetermined wavelength is emitted from the phosphor substrate. Two light is emitted, second brightness information indicating the second brightness that is the brightness of the second light is detected by the second light detection unit , and the second reference brightness that is the reference second brightness is detected. Sato, wherein the ratio of the second brightness second photodetecting unit is indicated by the second brightness information detected, the first correction coefficient for correcting the second brightness that is detected by the second light detector And the first correction coefficient corresponding to the second brightness indicated by the second brightness information detected by the second light detection unit is determined based on the first information associated with Based on the corrected second brightness, correcting the second brightness based on the first correction coefficient. The projector control method, wherein the output of the first light is adjusted, and the first correction coefficient is a coefficient for correcting a change in a detection result of the second light detection unit due to a change in the wavelength of the first light. .
One embodiment of the present invention is light in the polarization state from the polarization conversion element by emitting third light from the fourth light source to the polarization conversion element that emits incident light as light in a predetermined polarization state. The fourth light is emitted, the fourth brightness information indicating the fourth brightness which is the brightness of the fourth light is detected by the fourth light detection unit , and the fourth reference which is the fourth brightness serving as a reference. and brightness, the fourth and the ratio of the fourth brightness showing the fourth brightness information light detecting unit detects the second correction for correcting the fourth brightness detected by the fourth light detector And determining the second correction coefficient according to the fourth brightness indicated by the fourth brightness information detected by the fourth light detection unit based on the second information associated with the coefficient. The fourth brightness is corrected based on the second correction coefficient, and the corrected fourth brightness is corrected. And adjusting the output of the third light based on the second correction coefficient, wherein the second correction coefficient is a coefficient for correcting a change in a detection result of the fourth light detection unit due to a change in a polarization characteristic of the polarization conversion element. This is a control method.

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.

<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 this case, the blue light correction coefficient determination unit 93 reads the blue light correction coefficient corresponding to the red light attenuation coefficient indicated by the information input from the blue light attenuation ratio calculation unit 92, for example, to correct the blue light correction. 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 multiplication unit 84, a duty determination unit 85, a polarization change estimation unit 90b, a blue light wavelength change estimation unit 100, 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.

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

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

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

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

3R, 3G, 3B Light guiding optical system 4R, 4G, 4B Reflective liquid crystal panel (light modulation unit)
DESCRIPTION OF SYMBOLS 5 Cross dichroic prism 6 Projection optical system 9 1st lens array 10 2nd lens array 11 Polarization conversion element 12 Superimposition lens 25 Dichroic mirror 26, 27, 28 Polarization beam splitter (polarization separation element)
32R, 32G, 32B Condensing lenses 34R, 34G, 34B Polarizing plate 36R Red light sensor 36G Green light sensor 36B Blue light sensor 37 First aperture (incident angle limiting member)
38 Second stop (incident angle limiting member)
50, 50b Projector 51 Illumination device for blue light 52 Illumination device for yellow light 53 Blue laser diode array 54 Parallelizing lens 55 Condensing lens 56 Diffuser plate 57 Pickup lens 58 Parallelizing lens 59 Blue laser diode 61 Phosphor substrate 62 For excitation Laser diode 64, 64b, 64c Control unit 65, 65b, 65c Signal processing unit 66 Liquid crystal drive unit 67 PWM signal generation unit 68 Laser diode drive unit for excitation 69 Blue laser diode drive unit 70, 70b Adjustment unit 71 Light source 72 Light detection unit 73, 73b, 73c Correction unit 80, 80b, 80c Wavelength change estimation unit 81 Red light optical sensor reference value storage unit 82, 82b Red light attenuation ratio calculation unit 82c First temperature change ratio calculation unit 83, 83c Red light correction Coefficient determination unit 84 Red Multiplier for light 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 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 DESCRIPTION OF SYMBOLS 100 Blue light wavelength change estimation part 101 3rd correction coefficient determination part 102 Blue light addition part 110 Temperature sensor (temperature detection part)

Claims (11)

A second light source that emits first light to a phosphor substrate that emits light according to incident light, and emits second light that has a wavelength of a predetermined wavelength or more from the phosphor substrate;
A second light detection unit for detecting second brightness information indicating the second brightness that is the brightness of the second light;
A ratio between the second reference brightness, which is the second brightness serving as a reference, and the second brightness indicated by the second brightness information detected by the second light detection unit, and detected by the second light detection unit. The second brightness indicated by the second brightness information detected by the second light detection unit based on the first information associated with the first correction coefficient for correcting the second brightness. An adjustment that determines the first correction coefficient according to the first correction coefficient, corrects the second brightness based on the determined first correction coefficient, and adjusts the output of the first light based on the corrected second brightness. And
With
The first correction coefficient is a coefficient for correcting a change in the detection result of the second light detection unit due to a change in the wavelength of the first light.
projector.   2. The projector according to claim 1, wherein the second light detection unit detects the second brightness information related to the brightness of the second light different from the second light projected onto a screen. A temperature detection unit for detecting temperature information indicating the temperature;
The projector according to claim 1, wherein the adjustment unit adjusts the output of the first light based on temperature information detected by the temperature detection unit. A temperature detection unit for detecting temperature information indicating the temperature;
The adjustment unit estimates the wavelength of the second light with reference to the second brightness information detected by the second light detection unit and the temperature information detected by the temperature detection unit, and the estimated wavelength The projector according to claim 1, wherein the output of the first light is adjusted based on the projector. A fourth light source that emits third light to a polarization conversion element that emits incident light as light of a predetermined polarization state, and emits fourth light that is light of the polarization state from the polarization conversion element;
A fourth light detection unit for detecting fourth brightness information indicating the fourth brightness that is the brightness of the fourth light;
A ratio between the fourth reference brightness, which is the fourth brightness serving as a reference, and the fourth brightness indicated by the fourth brightness information detected by the fourth light detection unit, and detected by the fourth light detection unit. The fourth brightness indicated by the fourth brightness information detected by the fourth light detection unit based on the second information associated with the second correction coefficient for correcting the fourth brightness. An adjustment for determining the second correction coefficient according to the second correction coefficient, correcting the fourth brightness based on the determined second correction coefficient, and adjusting the output of the third light based on the corrected fourth brightness And
With
The second correction coefficient is a coefficient for correcting a change in the detection result of the fourth light detection unit due to a change in polarization characteristics of the polarization conversion element.
projector.   The projector according to claim 5, wherein the fourth light detection unit detects the fourth brightness information related to brightness of the fourth light different from the fourth light projected onto a screen. Further comprising a polarization separating element you separate the fourth light of the incident fourth light different polarization from the fourth light source,
It said fourth optical detector, of the fourth light the polarization separation element are separated, and detects the fourth brightness information on the brightness of different said fourth light and the fourth light to be projected on a screen The projector according to claim 5 or 6. A temperature detection unit for detecting temperature information indicating the temperature;
The projector according to claim 5, wherein the adjustment unit adjusts the output of the third light based on temperature information detected by the temperature detection unit. A temperature detection unit for detecting temperature information indicating the temperature;
The adjusting unit estimates and estimates the polarization state of the fourth light with reference to the fourth brightness information detected by the fourth light detection unit and the temperature information detected by the temperature detection unit. The projector according to any one of claims 5 to 7, wherein an output of the third light is adjusted based on the polarization state. By emitting the first light from the second light source to the phosphor substrate that emits light according to the incident light, the second light that is light having a wavelength of a predetermined wavelength or more is emitted from the phosphor substrate,
The second light detection unit detects the second brightness information indicating the second brightness that is the brightness of the second light ,
A second reference brightness is the second brightness as a reference, and the ratio of the second brightness indicated by the second brightness information by the second light detection unit detects is detected by the second light detector The second brightness indicated by the second brightness information detected by the second light detection unit based on the first information associated with the first correction coefficient for correcting the second brightness to be performed And determining the first correction coefficient according to the first correction coefficient, correcting the second brightness based on the determined first correction coefficient, and adjusting the output of the first light based on the corrected second brightness. ,
The first correction coefficient is a coefficient for correcting a change in the detection result of the second light detection unit due to a change in the wavelength of the first light.
Projector control method. By emitting the third light from the fourth light source to the polarization conversion element that emits the incident light as light of a predetermined polarization state, the fourth light that is the light in the polarization state is emitted from the polarization conversion element,
The fourth light detection unit detects fourth brightness information indicating the fourth brightness which is the brightness of the fourth light ,
A fourth reference brightness is the fourth brightness as a reference, and the ratio of the fourth brightness showing the fourth the fourth brightness information light detecting unit detects is detected by the fourth light detector The fourth brightness indicated by the fourth brightness information detected by the fourth light detection unit on the basis of second information associated with the second correction coefficient for correcting the fourth brightness. And determining the second correction coefficient according to the second correction coefficient, correcting the fourth brightness based on the determined second correction coefficient, and adjusting the output of the third light based on the corrected fourth brightness. ,
The second correction coefficient is a coefficient for correcting a change in the detection result of the fourth light detection unit due to a change in polarization characteristics of the polarization conversion element.
Projector control method.

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