Display device and control method for display device

Abstract

To provide a display that can properly monitor a deterioration of a liquid crystal panel, and a method for controlling a display.SOLUTION: In a projection type display 200, when blue (B) light is incident on a first liquid crystal panel 110B, radiant light Z radiated from the first liquid crystal panel 110B includes red (R) phosphorescence having a longer wavelength region than that of the blue (B) light due to a deterioration of liquid crystal material. In the display 200, an optical sensor device 1 is therefore provided behind a mirror 2106 formed of a dichroic mirror, based on a result of light reception within a band from 600 nm to 650 nm in the optical sensor device 1, the life of the first liquid crystal panel 110B is monitored, and a result of the monitoring is notified by an image or voice. Based on a result from the optical sensor device 1, an electrode for impurity adsorption provided in the first liquid crystal panel 110B is driven to sweep out ionic impurities from a display area.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a display device equipped with a liquid crystal panel and a control method thereof. [Background technology]

[0002] In a projection type display device, light emitted from a light source unit is irradiated onto a transmissive liquid crystal panel or a reflective liquid crystal panel, and the transmitted light or reflected light modulated by the liquid crystal panel is projected onto a screen. In such a display device, deterioration of the display device is likely to occur due to the fact that high-intensity light is emitted from the light source unit to the liquid crystal panel. Therefore, a technology has been proposed in which an optical sensor is provided in the display device, and the driving conditions of the display device are changed based on the detection results of the optical sensor (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2008-40016 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the technology described in Patent Document 1, an optical sensor detects the chromaticity or illuminance of light modulated by a liquid crystal panel, and determines the image quality based on the detection result to control a cooling fan. However, the technology in Patent Document 1 has a problem in that it is difficult to properly monitor the deterioration of the liquid crystal panel because it cannot detect whether the deterioration is caused by the liquid crystal panel or the light source. [Means for solving the problem]

[0005] In order to solve the above problems, a liquid crystal device according to one aspect of the present invention includes a first liquid crystal panel and a front When light in a first wavelength range is incident on the first liquid crystal panel To, The first liquid crystal panel The liquid crystal of This was caused by and an optical sensor device for detecting light in a wavelength range longer than the first wavelength range. The present invention is characterized by the above.

[0006] In one embodiment of the present invention, a method for controlling a display device having a liquid crystal panel includes: light in a first wavelength range is incident on the liquid crystal panel; This is caused by the liquid crystal emitting light. The above It is characterized by detecting light in a wavelength range longer than the first wavelength range. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is an explanatory diagram of a projection type display device according to a first embodiment of the present invention. [Diagram 2] 2 is a H-H′ cross-sectional view of the liquid crystal device shown in FIG. [Diagram 3] FIG. 2 is an explanatory diagram showing the planar configuration of the liquid crystal panel shown in FIG. [Figure 4] FIG. 4 is a cross-sectional view of the liquid crystal panel shown in FIG. [Diagram 5] 1 is a diagram illustrating the change over time in photoluminescence when liquid crystal is irradiated with light. [Figure 6] An explanatory diagram of the change in photoluminescence (phosphorescence) over time in an accelerated aging test of a liquid crystal panel. [Figure 7] An explanatory diagram of the change in photoluminescence (phosphorescence) over time in an accelerated aging test of a liquid crystal panel. [Figure 8] FIG. 4 is an explanatory diagram showing the electro-optical characteristics (VT characteristics) of a liquid crystal panel. [Figure 9] FIG. 4 is an explanatory diagram showing a flow of determining the life span of a liquid crystal panel. [Figure 10] FIG. 4 is an explanatory diagram showing a correction flow of a liquid crystal panel. [Figure 11] FIG. 2 is an explanatory diagram of a projection type display device according to a first modified example of the first embodiment of the present invention. [Figure 12]FIG. 11 is an explanatory diagram of a projection type display device according to a second modified example of the first embodiment of the present invention. [Figure 13] FIG. 11 is an explanatory diagram of a projection type display device according to a second embodiment of the present invention. [Figure 14] FIG. 11 is an explanatory diagram of a projection type display device according to a modified example of the second embodiment of the present invention. [Figure 15] FIG. 11 is an explanatory diagram of a display device according to a third embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] An embodiment of the present invention will be described with reference to the drawings. In the drawings referred to in the following description, each layer and each member is shown at a different scale so that they can be recognized on the drawings. In the following description, the liquid crystal panel is denoted by the reference numeral 110, and the corresponding colors are denoted by the reference numerals R, G, and B. However, when it is not necessary to specify the corresponding colors, the liquid crystal panel will be simply described as the liquid crystal panel 110.

[0009] 1. First embodiment 1-1.Projection type display device Fig. 1 is an explanatory diagram of a projection type display device 200 according to a first embodiment of the present invention. Fig. 2 is an explanatory diagram of a control system of the projection type display device 200 shown in Fig. 1.

[0010] The projection type display device 200 shown in Fig. 1 is provided with a white light source unit 2102 consisting of an array light source having a semiconductor laser, a lamp unit having a halogen lamp, or the like. The light source light emitted from the white light source unit 2102 is separated into three primary colors, red (R), green (G), and blue (B), by three mirrors 2104, 2105, and 2106 and two dichroic mirrors 2108 and 2109 arranged inside. The separated projection light is guided to light valves 100R, 100G, and 100B corresponding to red (R), green (G), and blue (B), respectively, and modulated. In Fig. 1, the light of blue (B) has a longer optical path than the other lights of red (R) and green (G), and therefore is guided through a blue (B) optical system 2121 including a relay lens (not shown) to prevent loss.

[0011] Each of the light valves 100R, 100G, and 100B has an incident-side polarization separation element 111 and an exit-side polarization separation element 112 on either side of a liquid crystal panel 110. Here, the wavelengths of red (R), green (G), and blue (B) light have the following relationship: B <G<R

[0012] Therefore, the display device 200 includes a liquid crystal panel 110, which receives light in a first wavelength range. a liquid crystal panel, a second liquid crystal panel to which light in a second wavelength range different from the first wavelength range is incident, and a first liquid crystal panel to which light in a second wavelength range different from the first wavelength range is incident. and a third liquid crystal panel onto which light in a third wavelength range, which is longer than the long wavelength range and the second wavelength range, is incident. Here, the first wavelength range is smaller than the second wavelength range. short wavelength range If this is the case, then the light of each wavelength and the liquid crystal panel Each of the channels 110 is defined as follows: First wavelength region light = Blue (B) light Second wavelength range light = Green (G) light Third wavelength range light = Red (R) light Liquid crystal panel 110 into which blue (B) light is incident = first liquid crystal panel 110B Liquid crystal panel 110 into which green (G) light is incident = second liquid crystal panel 110G Liquid crystal panel 110 into which red (R) light is incident = third liquid crystal panel 110R

[0013] The light modulated by the light valves 100R, 100G, and 100B enters a combining optical system 2112 consisting of a dichroic prism from three directions. In the combining optical system 2112, the red and blue light are reflected at 90 degrees, and the green light is transmitted. Therefore, after the images of each primary color are combined, a color image is projected by the projection optical system 2114 onto a projection target member 2120 such as a screen.

[0014] Furthermore, the display device 200 has an optical sensor device 1 on the light incident side of the liquid crystal panel 110. The optical sensor device 1 is configured to detect light in a wavelength range different from the light incident on the liquid crystal panel 110. As will be described later, the optical sensor device 1 detects radiated light Z emitted from the liquid crystal panel 110 when light is incident on the liquid crystal panel 110. This radiated light Z is photoluminescence of the liquid crystal of the liquid crystal panel 110, and is different from the light incident on the liquid crystal panel 110.

[0015] The optical sensor device 1 of this embodiment is disposed on the opposite side of the first liquid crystal panel 110B with respect to the mirror 2106 that guides blue light, which is light in the first wavelength range, to the first liquid crystal panel 110B, and detects radiated light Z in a wavelength range different from the first wavelength range. The optical sensor device 1 detects radiated light Z emitted from the first liquid crystal panel 110B when light in the first wavelength range is incident on the first liquid crystal panel 110B. The mirror 2106 reflects blue light B, which is light in the first wavelength range, and transmits light in other wavelength ranges. Therefore, the optical sensor device 1 can detect radiated light Z emitted from the light incident surface of the first liquid crystal panel 110B via the mirror 2106.

[0016] A camera or a spectrometer can be used for the optical sensor device 1. The optical sensor device 1 of this embodiment can adopt a mode in which the wavelength of light incident on the light receiving element is limited to 600 nm to 650 nm by a filter or the like, or a mode in which the intensity of light in the band from 600 nm to 650 nm is extracted from the result of light received by the light receiving element. In addition, the optical sensor device 1 may be provided with a condenser lens 11 between the mirror 2106 and the optical sensor device 1 in order to increase sensitivity.

[0017] The display device 200 of this embodiment is configured such that the dichroic mirror 2109 prevents red and green light from entering the optical system from the dichroic mirror 2109 to the first liquid crystal panel 110B. When the optical sensor device 1 observing the first liquid crystal panel 110B detects a change in light of a color different from blue light, it is presumed that a change has occurred in the first liquid crystal panel 110B. The display device 200 is also configured such that the dichroic mirror 2108 prevents red light from entering the optical system from the dichroic mirror 2108 to the second liquid crystal panel 110G. The display device 200 is also configured such that the dichroic mirror 2108 prevents blue and green light from entering the optical system from the dichroic mirror 2108 to the third liquid crystal panel 110R. Therefore, the optical sensor device 1 may be arranged on the opposite side of the dichroic mirror 2109 to the second liquid crystal panel 110G to observe light different from green and blue light. Furthermore, the optical sensor device 1 may be disposed on the opposite side of the mirror 2104 from the third liquid crystal panel 110R, and configured to observe light other than red light.

[0018] As shown in FIG. 2, the projection type display device 200 includes three liquid crystal panels 110 consisting of a first liquid crystal panel 110B, a second liquid crystal panel 110G, and a third liquid crystal panel 110R, and a control unit 70. The liquid crystal panel 110 includes a pixel region E in which a plurality of pixels P are arranged, and a drive circuit 105 that drives the plurality of pixels P. In the pixel region E of the liquid crystal panel 110, s scanning lines 32 extending in a first direction X and t data lines 34 extending in a second direction Y are formed. Each of s and t is an integer of 2 or more. The plurality of pixels P are arranged in s rows and t columns corresponding to the intersections of the scanning lines 32 and the data lines 34. Each of the plurality of pixels P includes a liquid crystal element CL. Although not shown, each of the plurality of pixels P includes a pixel switching element and a storage capacitance.

[0019] The driving circuit 105 includes a data line driving circuit 101 and a scanning line driving circuit 102, and supplies an image signal VD[j] that specifies the grayscale level to be displayed by each of the pixels P to each of the pixels P. j is an integer that satisfies 1≦j≦t. The scanning line driving circuit 102 supplies a scanning signal GS[i] to the scanning line 32 of the i-th row. i is an integer that satisfies 1≦i≦s. The data line driving circuit 101 supplies image signals VD[1] to VD[t] to the data lines 34 of the 1st row to the t-th row in synchronization with the selection of the scanning line 32 by the scanning line driving circuit 102. The liquid crystal element CL is driven by a voltage corresponding to the image signal VD[j], and performs optical modulation according to the electro-optical characteristic (VT characteristic) (see FIG. 8).

[0020] The control unit 70 includes an image processing unit 71, a timing signal generating unit 72, and a determination unit 2. The timing signal generating unit 72 generates a control signal CLT for controlling the driving circuit 105 and the image processing unit 71 based on a synchronization signal supplied from a higher-level device (not shown), and supplies the generated control signal CLT to the driving circuit 105 and the image processing unit 71. The timing signal generating unit 72 generates a polarity signal PL that specifies the polarity of the image signal VD[n], and supplies the polarity signal PL to the data line driving circuit 101. The data line driving circuit 101 sets the polarity of the image signal VD[n] according to the polarity signal PL. When an input video signal Vin representing an image to be displayed by the display device 200 is supplied from the higher-level device, the image processing unit 71 generates a grayscale signal VL indicating the grayscale level of the pixel P based on the input video signal Vin and the control signal CLT, and outputs the grayscale signal VL to the data line driving circuit 101. The determination unit 2 determines whether the intensity of the radiated light Z exceeds a predetermined value based on information from the optical sensor device 1. The image processing unit 71, the timing signal generating unit 72, and the determination unit 2 are realized by electronic circuits. The control unit 70 is configured as a processor. The image processing unit 71, the timing signal generating unit 72, and the determination unit 2 may be configured as modules executed by the processor.

[0021] 1-2. Overall configuration of the liquid crystal panel 110 FIG. 3 is an explanatory diagram showing a planar configuration of the liquid crystal panel 110 shown in FIG. 1. FIG. 4 is a cross-sectional view of the liquid crystal panel 110 shown in FIG. 3. In FIGS. 3 and 4, the liquid crystal panel 110 has a first substrate 10 and a second substrate 20 facing the first substrate 10, and the first substrate 10 and the second substrate 20 are bonded together via a frame-shaped sealant 40. A liquid crystal layer 50 is disposed between the first substrate 10 and the second substrate 20, inside the sealant 40. The first substrate 10 has a substrate body 10w made of a light-transmitting substrate such as a quartz substrate or a glass substrate, and the substrate body 10w to the first alignment film 18 correspond to the first substrate 10. The second substrate 20 has a substrate body 20w made of a light-transmitting substrate such as a quartz substrate or a glass substrate, and the substrate body 20w to the second alignment film 28 correspond to the second substrate 20.

[0022] The first substrate 10 is larger than the second substrate 20, and the sealant 40 is disposed along the outer edge of the second substrate 20. The liquid crystal layer 50 is made of a liquid crystal material having positive or negative dielectric anisotropy. The sealant 40 is made of an adhesive such as a thermosetting or ultraviolet-curing epoxy resin, and includes a spacer (not shown) for maintaining a constant distance between the first substrate 10 and the second substrate 20.

[0023] In the liquid crystal panel 110, a pixel region E is provided within an area surrounded by a sealant 40, and in the second substrate 20, a parting portion 21 is provided in a peripheral area F between the sealant 40 and the pixel region E, surrounding the periphery of the pixel region E. The parting portion 21 is formed of a light-shielding layer made of a metal or a metal oxide. The light-shielding layer may be formed as a black matrix that overlaps the boundary portion between adjacent pixels P on the second substrate 20 in a plan view.

[0024] In the first substrate 10, on one surface 10s facing the second substrate 20, a plurality of terminals 104 are arranged along one side outside the seal material 40, and a data line driving circuit 101 is provided between the terminals 104 and the pixel region E. On the one surface 10s side of the first substrate 10, on the outside of the pixel region E, a scanning line driving circuit 102 is provided along each of two sides adjacent to the side on which the terminals 104 are arranged, and an inspection circuit 103 and wiring 108 are provided along the side opposite to the side on which the terminals 104 are arranged. A plurality of wirings connected to the data line driving circuit 101 and the scanning line driving circuit 102 are each connected to a plurality of terminals 104. In the following description, the direction in which the terminals 104 are arranged is defined as the X-axis direction, and the direction perpendicular to the X-axis direction is defined as the Y-axis direction.

[0025] On one surface 10s of the first substrate 10, pixel electrodes 15 arranged in each of a plurality of pixels P arranged in the X-axis direction and the Y-axis direction in the pixel region E, and a first alignment film 18 covering the pixel electrodes 15 are provided. Although not shown, pixel switching elements, wiring, and the like are also provided on one surface 10s of the first substrate 10. The pixel electrodes 15 are made of a translucent conductive film such as ITO (Indium Tin Oxide).

[0026] On one surface 20s of the second substrate 20 facing the first substrate 10, a parting portion 21, a planarizing film 22 covering the parting portion 21, a common electrode 23 covering the planarizing film 22, and a second alignment film 28 covering the common electrode 23 are provided. The parting portion 21 overlaps the scanning line driving circuit 102 and the inspection circuit 103 in a planar view. The planarizing film 22 is made of an inorganic material such as silicon oxide. The common electrode 23 is made of ITO or the like, and is electrically connected to a terminal 104 via a vertical conductive portion 106 provided between the first substrate 10 and the second substrate 20 and a wiring provided on the first substrate 10.

[0027] The first alignment film 18 and the second alignment film 28 are selected based on the optical design of the liquid crystal panel 110. The first alignment film 18 and the second alignment film 28 are made of an inorganic alignment film containing an inorganic material such as SiOx (silicon oxide) formed by a vapor phase growth method such as deposition. In this case, the first alignment film 18 and the second alignment film 28 align liquid crystal molecules having negative dielectric anisotropy approximately vertically. The first alignment film 18 and the second alignment film 28 may be made of an organic alignment film such as polyimide having a rubbed surface. In this case, the organic alignment film aligns liquid crystal molecules having positive dielectric anisotropy approximately horizontally.

[0028] The liquid crystal panel 110 thus configured is a transmissive type. Therefore, depending on the optical design of the polarizing elements arranged on each of the light entrance side and exit side of the liquid crystal panel 110, the liquid crystal panel 110 is configured as a normally white mode liquid crystal device in which the transmittance of the pixel P is maximum in the absence of applied voltage, or a normally black mode liquid crystal device in which the transmittance of the pixel P is minimum in the absence of applied voltage. In the following description, an optical design of a normally black mode is applied by using inorganic alignment films as the first alignment film 18 and the second alignment film 28, and using a liquid crystal material having negative dielectric anisotropy for the liquid crystal layer 50.

[0029] The first alignment film 18 and the second alignment film 28 are inorganic alignment films, and are composed of an aggregate of columnar columns grown by obliquely evaporating inorganic materials such as silicon oxide. Therefore, in the liquid crystal layer 50, the liquid crystal molecules are aligned substantially vertically (VA) with a pretilt angle of 3° to 5° with respect to the normal direction to the first substrate 10 and the second substrate 20. When a drive signal is applied between the pixel electrode 15 and the common electrode 23, the inclination of the liquid crystal molecules changes depending on the direction of the electric field generated between the pixel electrode 15 and the common electrode 23.

[0030] The oblique deposition direction when forming the first alignment film 18 on the first substrate 10 is, for example, the direction indicated by the arrow C1 in FIG. 1, which is a direction that forms an angle θa with the Y-axis direction. The oblique deposition direction when forming the second alignment film 28 on the second substrate 20 is, for example, the direction indicated by the arrow C2 in FIG. 1, which is a direction that forms an angle θb with the Y-axis direction. The alignment direction of the liquid crystal molecules is determined by the deposition direction. The angles θa and θb are, for example, 45 degrees. The direction of oblique deposition when forming the first alignment film 18 on the first substrate 10 is opposite to the direction of oblique deposition when forming the second alignment film 28 on the second substrate 20.

[0031] The pixel region E has a display region E1 in which display pixels P1 that directly contribute to image display are arranged among the multiple pixels P, and a dummy pixel region E2 surrounding the display region E1, which has multiple dummy pixels P2 that do not directly contribute to image display among the multiple pixels P. Therefore, among the multiple pixel electrodes 15, the pixel electrode 15 provided in the display pixel P1 is a first pixel electrode 151 that is referred to as an effective pixel electrode or the like, and the pixel electrode 15 provided in the dummy pixel P2 is a second pixel electrode 152 that is referred to as a dummy pixel electrode or the like.

[0032] In this embodiment, since the liquid crystal panel 110 is in a normally black mode, a fixed potential or an AC potential that causes the dummy pixel P2 to display black is applied to the second pixel electrode 152 regardless of the display state of the display pixel P1. However, in this embodiment, the parting portion 21 is formed in a region that overlaps with the peripheral region F and the dummy pixel region E2 in a planar view, so that the dummy pixel P2 is not visible. Note that although the parting portion 21 overlaps with the peripheral region F in a planar view, it may be provided so as not to overlap with the dummy pixel region E2 in a planar view. In this case, the dummy pixel region E2 functions as an electronic parting that constitutes a parting together with the parting portion 21.

[0033] 1-3. Aging of LCD panels and photoluminescence The display quality of the liquid crystal panel 110 may change over time due to long-term use. In particular, in the liquid crystal panel 110 employed in the projection-type display device 200 having a high-brightness light source such as a laser, light with a high luminous flux density is incident on the liquid crystal panel 110, so the display quality tends to deteriorate over time. One of the factors that may cause the display quality of the liquid crystal panel 110 to deteriorate is the deterioration of the liquid crystal itself, and it is presumed that the composition and orientation characteristics of the liquid crystal molecules change due to irradiation with light.

[0034] The inventors of the present application have found that light emission presumably due to photoluminescence from liquid crystals can be detected during an accelerated aging test for observing the aging of liquid crystal panel 110. Specifically, strong red light was observed in liquid crystal panel 110 that was continuously irradiated with blue light. This red light is presumed to be photoluminescence caused by deteriorated liquid crystals. The radiated light Z shown in FIG. 1 is photoluminescence (phosphorescence) from liquid crystal panel 110.

[0035] Figure 5 is an explanatory diagram of the change over time in photoluminescence when light is irradiated onto liquid crystal. The horizontal axis is the measured wavelength, and the vertical axis is the light intensity observed in liquid crystal irradiated with blue light. The solid line L0 shows the initial spectrum when blue light irradiation begins, and the dashed line L1 shows the spectrum after blue light has been irradiated for a certain period of time. It is presumed that the spectrum other than that corresponding to the incident light is based on the photoluminescence of liquid crystal molecules or degraded liquid crystal molecules.

[0036] As shown in Figure 5, when blue light with an intensity peak near 450 nm is continuously irradiated onto the liquid crystal for a certain period of time, the intensity of the spectrum of the emitted light from the liquid crystal increases. In particular, the intensity of the band W with wavelengths from 550 nm to 650 nm increases, and it is observed as light with an increased proportion of red components. When electrons transition between liquid crystal molecules, a certain amount of light is emitted, but when liquid crystal molecules that have been degraded by photochemical reactions or the like are present, it is presumed that emitted light includes phosphorescence with a wavelength of 550 nm to 650 nm is emitted.

[0037] 6 and 7 are explanatory diagrams of the change over time of photoluminescence (phosphorescence) in an accelerated deterioration test of the liquid crystal panel 110. FIG. 6 is a diagram showing the spectrum at test times T0, T1, T2, T3, and T4, respectively, where the horizontal axis is the measurement wavelength and the vertical axis is the light intensity observed in the liquid crystal panel 110. FIG. 7 is a diagram showing the change over time of the light intensity in the band W from 500 nm to 650 nm. The horizontal axis of FIG. 7 is the test time, and the vertical axis is the light intensity observed in the liquid crystal panel 110. FIG. 7 shows the points corresponding to the test times T0, T1, T2, T3, and T4 shown in FIG. 6. In the accelerated deterioration test shown in FIG. 6 and FIG. 7, blue light with a high luminous flux density was irradiated onto the liquid crystal panel 110, and the liquid crystal panel 110 was observed from the light incident side by a device equivalent to the optical sensor device 1.

[0038] 8 is an explanatory diagram showing the electro-optical characteristics (VT characteristics) of the liquid crystal panel 110, where the vertical axis indicates the transmittance and the horizontal axis indicates the voltage applied to the liquid crystal element LC. VT curves of the liquid crystal panel 110 corresponding to test times T0, T3, and T4 are shown.

[0039] The main factor for the change in light intensity over time observed in the liquid crystal panel 110 is the change in the photoluminescence intensity of the liquid crystal panel 110 over time. The test time T0 indicates the initial state, and T0 < T1 < T2 < T3 < T4. By irradiating with blue light, the intensity of the spectrum of the emitted light due to the photoluminescence of the liquid crystal increases. At test times T1 and T2, in the band W from 500 nm to 650 nm, the intensity of the photoluminescence from the liquid crystal panel 110 increases. At test times T3 and T4, further, the intensity of the photoluminescence in the entire measured wavelength range increases, and the intensity of the photoluminescence in the band W from 500 nm to 650 nm increases significantly. The test times T3 and T4 are 1.1 times and 1.2 times the time of the test time T2 respectively, and their photoluminescence intensities are 1.5 times and more than 3 times the photoluminescence intensity of the test time T2 respectively. The V-T curve of the liquid crystal panel 110 at the test time T3 changes in the dark direction, and the V-T curve of the liquid crystal panel 110 at the test time T4 changes in the bright direction, and the display quality of the liquid crystal panel 110 deteriorates. It can be understood that the deterioration of the liquid crystal panel 110 progresses rapidly from the test time T3. Therefore, the deterioration of the liquid crystal panel 110 can be grasped by the change in the intensity of the photoluminescence of the liquid crystal panel 110. Incidentally, it is presumed that the factor for the increase in the intensity of the photoluminescence of the liquid crystal panel 110 is the increase in the concentration of deteriorated liquid crystal molecules. After the test time T4, the liquid crystal molecules deteriorate further, and the liquid crystal panel 110 can no longer recover the display quality even by correction or the like, and the life of the liquid crystal panel 110 comes to an end. As a judgment of the life, for example, as shown in FIG. 7, the time point when the intensity I0 of the photoluminescence observed between the test time T2 and the test time T3 is detected is judged to be the life of the liquid crystal panel 110. The intensity I0 of the photoluminescence can be set to the limit value I0 corresponding to the liquid crystal panel 110.

[0040] Therefore, by detecting the intensity of the photoluminescence emitted from liquid crystal panel 110, it is possible to monitor the deterioration of the liquid crystal and the deterioration of liquid crystal panel 110 caused by the deterioration of the liquid crystal. When blue light is continuously irradiated onto the liquid crystal for a certain period of time, the radiated light Z emitted from liquid crystal panel 110 also contains fluorescent light with a wavelength of 600 nm to 650 nm. Also, the shorter the wavelength of the light irradiated onto the liquid crystal, the more likely it is that deterioration due to photochemical reactions and the like will progress.

[0041] 1-4. Monitoring of Deterioration of Liquid Crystal Panel 110 In this embodiment, as shown in Fig. 1 and Fig. 2, among the first liquid crystal panel 110B, the second liquid crystal panel 110G, and the third liquid crystal panel 110R, the first liquid crystal panel 110B is provided with an optical sensor device 1 that detects radiated light Z emitted from the first liquid crystal panel 110B when light in a first wavelength range is incident on the first liquid crystal panel 110B, and the optical sensor device 1 detects radiated light Z in a wavelength range longer than the first wavelength range. More specifically, the optical sensor device 1 detects phosphorescence with a wavelength of 600 nm to 650 nm. Here, the optical sensor device 1 can adopt a mode in which the wavelength of the light incident on the light receiving element is limited to 600 nm to 650 nm by a filter or the like, or a mode in which the intensity of light in the band of 600 nm to 650 nm is extracted from the result of light received by the light receiving element.

[0042] 1, in this embodiment, a dichroic mirror that reflects blue light, which is light in the first wavelength range, and transmits red light, which is light in a third wavelength range, is used as the most downstream mirror 2106 that guides blue light, which is light in the first wavelength range, out of the light emitted from the white light source unit 2102, to the first liquid crystal panel 110B, and the photosensor device 1 is disposed on the opposite side of the mirror 2106 to the first liquid crystal panel 110B. Therefore, the photosensor device 1 can detect radiated light Z emitted from the light incident surface of the first liquid crystal panel 110B via the mirror 2106.

[0043] 2, the present embodiment further includes a determination unit 2 that determines the lifespan of the first liquid crystal panel 110B based on the result of detection of the radiated light Z having a wavelength of 600 nm to 650 nm by the optical sensor device 1. The determination unit 2 also determines whether or not the intensity of the radiated light Z, which is photoluminescence, has exceeded a limit value I0, and notifies the user when the intensity of the radiated light Z has exceeded the limit value I0.

[0044] More specifically, the judgment unit 2 is set with a limit value I0 (see FIG. 7) corresponding to the life of the first liquid crystal panel 110B for the intensity of the radiated light Z having a wavelength of 600 nm to 650 nm. The judgment unit 2 notifies the user of the remaining time of the liquid crystal panel 110 by using an image or the like based on the detected intensity of the radiated light Z. When the intensity of the radiated light Z exceeds the limit value I0, the judgment unit 2 notifies the user of the fact that the first liquid crystal panel 110B has reached the end of its life by using an image, a sound, or the like. The image may be superimposed on an image signal generated by the image processing unit 71 and displayed or projected on the liquid crystal panel 110. A notification means for notifying the user of the fact by using an image, a sound, or the like may also be provided. FIG. 9 shows a flow for notifying the user of the life of the first liquid crystal panel 110B when the intensity of the radiated light Z exceeds the limit value I0. The judgment unit 2 monitors the photoluminescence of the first liquid crystal panel 110B via the optical sensor device 1 (step S1), and when it determines that the intensity of the photoluminescence has exceeded the limit value I0 (step S2: YES), it notifies the user that the first liquid crystal panel 110B has reached the end of its life or the time remaining until its end of life (step S3).

[0045] In addition, the judgment unit 2 may not only notify the lifespan of the first liquid crystal panel 110B, but also correct the driving of the first liquid crystal panel 110B to suppress deterioration of display quality. The judgment unit 2 instructs the image processing unit 71 to correct the gradation signal VL so as to approach the VT curve corresponding to the test time T0 shown in FIG. 7. The driving circuit 105 supplies a corrected image signal VD[j] to each of the multiple pixels P based on the corrected gradation signal VL. As shown in FIG. 10, the judgment unit 2 monitors the radiated light Z, which is photoluminescence of the first liquid crystal panel 110B, via the optical sensor device 1 (step S11), and when it determines that the intensity of the radiated light Z exceeds the threshold I1 (step S12: YES), it determines whether the driving of the first liquid crystal panel 110B can be corrected (step S13). If the driving of the first liquid crystal panel 110B can be corrected, the determination unit 2 corrects the driving of the first liquid crystal panel 110B (step S15), and if the driving of the first liquid crystal panel 110B cannot be corrected, the determination unit 2 notifies that the first liquid crystal panel 110B has reached the end of its life (step S14). For example, the determination unit 2 calculates a correction amount for bringing the VT curves corresponding to the test times T2 and T3 shown in FIG. 7 closer to the VT curve at the test time T0 through an experiment or the like, and stores the calculated correction amount in association with the light intensity of the radiant light Z corresponding to the test times T2 and T3, respectively. If the optical sensor device 1 detects the threshold value I1, and the image processing unit 71 is able to correct the grayscale signal VL based on the corresponding correction amount, the determination unit 2 instructs the image processing unit 71 to correct the grayscale signal VL. For example, the threshold value I1 is the light intensity of the radiant light Z corresponding to the test time T2 or T3 in FIG. 7, and the correction of the driving of the first liquid crystal panel 110B is possible. When the light intensity of the radiated light Z corresponding to the test time T4 in FIG. 7 is equal to the threshold value I1, the driving of the first liquid crystal panel 110 cannot be corrected.

[0046] The monitoring of the radiated light Z emitted from the first liquid crystal panel 110B is performed during a period in which the first liquid crystal panel 110B is performing a display operation in the display device 200. Alternatively, the monitoring of the radiated light Z emitted from the first liquid crystal panel 110B may be performed during a period in which the first liquid crystal panel 110B is irradiated with blue light in the first wavelength range from the white light source unit 2102 and during a period in which the first liquid crystal panel 110B is halting its display operation. Alternatively, a mechanism for irradiating the first liquid crystal panel 110B with blue light in the first wavelength range may be provided as a separate mechanism.

[0047] In this manner, in this embodiment, the optical sensor device 1 is provided for detecting radiated light Z in the third wavelength range emitted when light in the first wavelength range is incident on the first liquid crystal panel 110B, and the radiated light Z is phosphorescence corresponding to deterioration of liquid crystal molecules. Therefore, based on the detection result by the optical sensor device 1, deterioration of the liquid crystal in the first liquid crystal panel 110B can be monitored.

[0048] In this embodiment, the optical sensor device 1 is provided for the first liquid crystal panel 110B, which has the shortest wavelength of incident light, among the first liquid crystal panel 110B, the second liquid crystal panel 110G, and the third liquid crystal panel 110R. Therefore, even if the optical sensor device 1 is not provided for the other liquid crystal panels, the second liquid crystal panel 110G and the third liquid crystal panel 110R, it is possible to monitor deterioration of the liquid crystal panel 110 in the display device 200.

[0049] 1-5. Modification 1 of the first embodiment 11 is an explanatory diagram of a projection type display device 200 according to Modification 1 of the first embodiment of the present invention, in which the optical sensor device 1 is disposed on the opposite side of the mirror 2105 from the first liquid crystal panel 110B. Note that since the basic configuration of this embodiment is similar to that of the first embodiment, the same reference numerals are used to denote common parts, and the description thereof will be omitted.

[0050] 1, the most downstream mirror 2106 is a dichroic mirror, but as shown in Fig. 11, the emitted light Z in the third wavelength range emitted from the first liquid crystal panel 110B may be detected via a combining optical system 2112 and mirrors 2106 and 2105. A dichroic mirror that reflects blue and red light is used as mirror 2106, and a dichroic mirror that reflects blue light and transmits red light is used as mirror 2105.

[0051] 1-6. Modification 2 of the first embodiment 12 is an explanatory diagram of a projection type display device 200 according to a second modification of the first embodiment of the present invention. Since the basic configuration of this embodiment is similar to that of the first embodiment, the same reference numerals are used to denote common parts, and their description will be omitted. In the display device 200 of this embodiment, a light blocking member 4 is provided in the red light path toward the third liquid crystal panel 110R to prevent red light from leaking toward the optical sensor device 1. Therefore, the optical sensor device 1 can accurately detect phosphorescence in the third wavelength range emitted from the first liquid crystal panel 110B.

[0052] 2. Second embodiment 13 is an explanatory diagram of a projection type display device 300 according to a second embodiment of the present invention. Since the basic configuration of this embodiment is similar to that of the second embodiment, the same reference numerals are given to the common parts and their description will be omitted.

[0053] The projection type display device 200 according to the first embodiment uses a transmissive liquid crystal panel 110, but the projection type display device 300 of this embodiment uses a reflective liquid crystal panel 110. More specifically, in the liquid crystal panel 110 shown in Fig. 4, the pixel electrodes 15 are made of a reflective metal such as aluminum.

[0054] In the display device 300, the light source light emitted from the white light source unit 3102 is separated into three primary colors, red (R), green (G), and blue (B), by two dichroic mirrors 3107 and 3108 arranged inside, and a mirror 3109, and the separated light proceeds in a predetermined direction. Specifically, the dichroic mirror 3107 reflects red (R) light and transmits other colors of light among the incident light, thereby separating the incident light into red (R) light and other colors of light. The mirror 3109 is arranged on the optical path of the other colors of light separated by the dichroic mirror 3107. The dichroic mirror 3108 reflects green (G) light and transmits blue (B) light among the incident light, thereby separating the incident light into green (G) light and blue (B) light.

[0055] Here, in the display device 300, polarizing beam splitters 3086B, 3086GB, and 3086R are provided between the first liquid crystal panel 110B, the second liquid crystal panel 110G, and the third liquid crystal panel 110R and a synthesis optical system 3112 consisting of a dichroic prism, which synthesizes the incident optical path of the light source light to the liquid crystal panel 110 and the exit optical path of the modulated light from the liquid crystal panel 110. Therefore, the blue light transmitted through the dichroic mirrors 3107 and 3108 is incident on the polarizing beam splitter 3086B and converted into polarized light, which is then irradiated onto the first liquid crystal panel 110B. The green light transmitted through the dichroic mirror 3107 and reflected by the dichroic mirror 3108 is incident on the polarizing beam splitter 3086G and converted into polarized light, which is then irradiated onto the second liquid crystal panel 110G. The red light reflected by dichroic mirror 3107 enters polarizing beam splitter 3086R where it is converted into polarized light, and is then irradiated onto third liquid crystal panel 110R.

[0056] The first liquid crystal panel 110B, the second liquid crystal panel 110G, and the third liquid crystal panel 110R modulate and reflect the incident light, and emit the modulated light toward the polarizing beam splitters 3086R, 3086G, and 3086B corresponding to each color. The polarizing beam splitters 3086R, 3086G, and 3086B cause the modulated light incident from the first liquid crystal panel 110B, the second liquid crystal panel 110G, and the third liquid crystal panel 110R to enter the combining optical system 3112. The combining optical system 3112 combines the modulated light of the three colors and emits it toward the projection optical system 3114, and the projection optical system 3114 enlarges and projects the color image onto a projection member 3120 such as a screen.

[0057] In this embodiment, the optical sensor device 1 is disposed on the opposite side of the polarizing beam splitter 3086B to the first liquid crystal panel 110B. Therefore, when blue light in the first wavelength range is incident on the first liquid crystal panel 110B, the optical sensor device 1 can detect red radiation light Z in the third wavelength range emitted by the first liquid crystal panel 110B. Although not shown, it is preferable that a light blocking member is provided on the red optical path toward the third liquid crystal panel 110R to prevent the red light from leaking toward the optical sensor device 1, as in the second modification of the first embodiment.

[0058] 2-1. Modification of the second embodiment FIG. 14 is an explanatory diagram of a projection type display device 300 according to a modified example of the second embodiment of the present invention. Since the basic configuration of this embodiment is the same as that of the second embodiment, the same reference numerals are attached to the common parts and the description thereof is omitted. In the display device 300 shown in FIG. 13, the optical sensor device 1 is disposed on the opposite side of the first liquid crystal panel 110B with respect to the polarizing beam splitter 3086B. However, as shown in FIG. 14, the optical sensor device 1 may be disposed on the side of the polarizing beam splitter 3086B. In addition, in order to increase the sensitivity, a condenser lens 11 may be provided between the optical sensor device 1 and the polarizing beam splitter 3086B.

[0059] 3. Third embodiment FIG. 15 is an explanatory diagram of a display device according to a third embodiment of the present invention, and is a cross-sectional view showing an enlarged configuration of an end portion of the first liquid crystal panel 110B. In the liquid crystal panel 110 described with reference to FIG. 2 and the like, when an image signal is supplied to the pixel electrode 15 to drive the liquid crystal layer 50, the liquid crystal molecules vibrate, and a flow of the liquid crystal molecules occurs in the oblique deposition direction indicated by the arrows C1 and C2 in FIG. 2. Therefore, when ionic impurities are generated when the liquid crystal material is deteriorated by photochemical reaction or the like, the ionic impurities move toward the corners Ea and Eb of the pixel region E along the flow of the liquid crystal molecules, and tend to be unevenly distributed in the corners Ea and Eb. In the region where such uneven distribution of ionic impurities occurs, the voltage applied to the liquid crystal layer 50 decreases, and the light modulation characteristics decrease. In addition, among the first liquid crystal panel 110B, the second liquid crystal panel 110G, and the third liquid crystal panel 110R, the first liquid crystal panel 110B, which receives light with the lowest wavelength range, experiences significant deterioration of the liquid crystal material due to photochemical reaction or the like.

[0060] Therefore, in this embodiment, an electrode 130 for attracting impurities that are present in the liquid crystal layer 50 in the display region E1 to the outside of the display region E1 is provided in the peripheral region F between the sealant 40 and the pixel region E on the first substrate 10, and in the first liquid crystal panel 110B, the electrode 130 is driven based on the detection result of the intensity of the radiated light Z by the optical sensor device 1 shown in Fig. 1 etc. For example, an AC signal Vt is applied to the electrode 130, the potential of which alternates between positive and negative polarities when the common potential Vcom applied to the common electrode 23 is taken as the reference potential.

[0061] More specifically, when the intensity of the radiated light Z detected by the optical sensor device 1 becomes higher than a set value, the electrode 130 is driven. Therefore, while the electrode 130 is positive, anionic impurities among ionic impurities generated due to deterioration of the liquid crystal material are attracted to the electrode 130. Meanwhile, while the electrode 130 is negative, cationic impurities among ionic impurities generated due to deterioration of the liquid crystal material are attracted to the electrode 130. As a result, impurities present in the liquid crystal layer 50 in the display region E1 are swept out from the display region E1 to the peripheral region F, so that the ionic impurities are less likely to be concentrated in the corners of the display region E1.

[0062] Here, the electrode 130 is provided at least between the corner of the pixel region E where ionic impurities are likely to be unevenly distributed and the corner of the sealant 40. In this embodiment, the electrode 130 is provided at least between two corners Ea, Eb in the diagonal direction of the pixel region E and two corners 40a, 40b in the diagonal direction of the sealant 40, corresponding to the oblique deposition direction (the alignment direction of liquid crystal molecules) indicated by the arrows C1, C2 in FIG. 2. However, the electrode 130 may be provided in a frame shape so as to surround the pixel region E between the pixel region E and the sealant 40. Also, a plurality of electrodes 130 may be arranged in parallel, and an AC potential may be applied to adjacent electrodes 130. Also, a DC potential may be applied to the electrode 130. Also, the electrode 130 may be provided not only in the first liquid crystal panel 110B but also in the second liquid crystal panel 110G and the third liquid crystal panel 110B.

[0063] 4. Other embodiments In the above embodiment, the first liquid crystal panel corresponding to the first wavelength range is the liquid crystal panel 110 corresponding to blue (B), but the first liquid crystal panel corresponding to the first wavelength range may be the liquid crystal panel 110 corresponding to green (G). In this case, the light of each wavelength and the liquid crystal panel 110 are defined as follows. In this case, the optical sensor device 1 is provided in the liquid crystal panel 110 corresponding to green (G). First wavelength range light = Green (G) light Second wavelength range light = Blue (B) light Third wavelength range light = Red (R) light Liquid crystal panel 110 into which green (G) light is incident = first liquid crystal panel Liquid crystal panel 110 into which blue (B) light is incident = second liquid crystal panel Liquid crystal panel 110 into which red (R) light is incident = third liquid crystal panel

[0064] Alternatively, the optical sensor device 1 may be provided on both the liquid crystal panel 110 corresponding to blue light and the liquid crystal panel 110 corresponding to green light.

[0065] 5. Other Electronic Devices As the light source unit, light emitting elements such as LEDs and laser diodes that emit light of each color may be used, and the color light emitted from the light emitting elements may be used as light source light. Moreover, electronic devices equipped with the liquid crystal panel 110 to which the present invention is applied are not limited to the projection type display devices 200 and 300 of the above embodiments. For example, the liquid crystal panel 110 to which the present invention is applied may be used in electronic devices such as a projection type HUD (head-up display), a direct viewing type HMD (head-mounted display), a personal computer, a digital still camera, and a liquid crystal television. [Explanation of symbols]

[0066] 1...optical sensor device, 2...determination unit, 4...light shielding member, 10...first substrate, 15...pixel electrode, 18...first alignment film, 20...second substrate, 21...partition unit, 23...common electrode, 28...second alignment film, 40...sealing material, 50...liquid crystal layer, 70...control unit, 100B, 100G, 100R...light valve, 110...liquid crystal panel, 110B...first liquid crystal panel, 110G...second liquid crystal panel, 110R...third liquid crystal panel, 111...incident side polarization separation element, 112...exit side polarization separation element, 130...electrode, 200, 300...display device, 2102, 3102...white light source unit, 3107, 3108...dichroic mirror, 2112, 3112...combining optical system, 2114, 3114...projection optical system, E...pixel region, E1...display region, E2...dummy pixel region, F...periphery region, P...pixel, X...first direction, Y...second direction, Z...radiated light

Claims

1. A first liquid crystal panel; When light in a first wavelength range is incident on the first liquid crystal panel, the liquid crystal of the first liquid crystal panel emits light. an optical sensor device for detecting light having a wavelength range longer than the first wavelength range generated by the irradiation of the light; A display device comprising:

2. 2. The display device according to claim 1, a second liquid crystal panel to which light in a second wavelength range different from the first wavelength range is incident; a third liquid crystal panel into which light in a third wavelength range, which is longer than the first wavelength range and the second wavelength range, is incident; Nell and having The light in the first wavelength range modulated by the first liquid crystal panel, the light in the second wavelength range modulated by the third liquid crystal panel, A synthesis optical system that synthesizes and outputs light of three wavelength regions; a projection optical system that projects the light emitted from the synthesis optical system; A display device comprising:

3. 3. The display device according to claim 2, The display device, wherein the first wavelength range is a shorter wavelength range than the second wavelength range.

4. 4. The display device according to claim 3, The light in the wavelength range longer than the first wavelength range is the light in the third wavelength range. Place.

5. 5. The display device according to claim 4, The light in the third wavelength range that is incident on the third liquid crystal panel and that is emitted from the third liquid crystal panel a light blocking member that blocks the light in the third wavelength range from being incident on the optical sensor device; A display device comprising:

6. The display device according to any one of claims 2 to 5, the first liquid crystal panel is a transmissive liquid crystal panel, The optical sensor device detects the first wave emitted from the light-incident surface of the first liquid crystal panel. A display device that detects light in a longer wavelength range than the long wavelength range.

7. 7. The display device according to claim 6, A diode that guides light in the first wavelength range out of the light emitted from the light source to the first liquid crystal panel. Equipped with a Loic Miller, The optical sensor device is disposed on the opposite side of the dichroic mirror from the first liquid crystal panel. a dichroic mirror arranged on the opposite side to the first wavelength region, and A display device characterized by detecting

8. 8. The display device according to claim 7, A condenser lens is provided between the optical sensor device and the dichroic mirror. A display device comprising:

9. The display device according to any one of claims 2 to 5, the first liquid crystal panel is a reflective liquid crystal panel, The optical sensor device detects the first wavelength emitted from the emission side surface of the first liquid crystal panel. A display device that detects light in a wavelength range longer than the visible range.

10. 10. The display device according to claim 9, An incident optical path of light from a light source to the first liquid crystal panel and an exit optical path of modulated light from the first liquid crystal panel and a polarizing beam splitter for combining the first and second paths, The optical sensor device detects wavelengths longer than the first wavelength range through the polarizing beam splitter. A display device characterized by detecting light in a wavelength range.

11. The display device according to any one of claims 1 to 10, Based on the detection result of the intensity of light in a wavelength range longer than the first wavelength range by the optical sensor device, a determination unit for determining a lifespan of the first liquid crystal panel by detecting a lifespan of the first liquid crystal panel.

12. The display device according to any one of claims 1 to 10, The optical sensor detects that the intensity of light in a wavelength region longer than the first wavelength region exceeds a set value. A display device comprising a notification means for notifying.

13. The display device according to any one of claims 1 to 10, The first liquid crystal panel draws impurities present in the liquid crystal layer in the display area to the outside of the display area. Equipped with electrodes for suction of impurities, Based on the detection result of the intensity of light in a wavelength range longer than the first wavelength range by the optical sensor device, and driving the electrodes by a voltage applied to the electrodes.

14. The display device according to any one of claims 1 to 13, The optical sensor device is configured to detect the first liquid crystal panel during a period in which the first liquid crystal panel is performing a display operation. A display device that detects light in a wavelength range longer than the wavelength range.

15. A method for controlling a display device having a liquid crystal panel, comprising: Light in a first wavelength range is incident on the liquid crystal panel; The light having a wavelength region longer than the first wavelength region, which is generated by the liquid crystal of the liquid crystal panel emitting light, 23. A method for controlling a display device, comprising: detecting a signal output from the display device;

Images