Projection type display device

Abstract

The invention provides a projection type display device which can realize high-resolution color display at low cost. A projection-type display device includes: a liquid crystal panel (100a) that generates a first image; a liquid crystal panel (100b) that generates a second image; a prism that synthesizes the first image and a second image shifted in the lateral direction with respect to the first pixel and emits the synthesized image; an optical path shift element that shifts the optical path of the output image from the prism; and a display control circuit that controls the liquid crystal panel and the optical path shift element, the display control circuit supplying data signals of odd-numbered rows of the video pixels to the liquid crystal panel (100a) during odd-numbered field periods, supplying data signals of even-numbered rows to the liquid crystal panel (100b), supplying data signals of even-numbered rows to the liquid crystal panel (100a) during even-numbered field periods, and supplying data signals of even-numbered rows to the liquid crystal panel (100b) during even-numbered field periods. Data signals of odd-numbered rows are supplied to a liquid crystal panel (100b), and a display control circuit controls an optical path shift element to shift an optical path in the longitudinal direction.

Description

Technical Field

[0001] The present invention relates to a projection type display device. Background Art

[0002] The following technology has been proposed: in a projection display device that projects image light generated by a liquid crystal panel or the like onto a screen or the like, a first optical image generated by a first optical system and a second optical image generated by a second optical system are offset and synthesized, and then projected to achieve high resolution (for example, refer to Patent Document 1).

[0003] Specifically, when color display is realized in the above-mentioned technology, the structure is as follows. That is, the structure is as follows: in the first optical system, the images based on the three liquid crystal panels are synthesized as the first optical image by using the first dichroic prism, and in the second optical system, the images based on the three liquid crystal panels are synthesized as the second optical image by using the second dichroic prism, and the first optical image and the second optical image are synthesized by using the prism.

[0004] Patent Document 1: Japanese Patent Application Publication No. 2010-181670

[0005] However, the above technology requires not only a total of six liquid crystal panels but also three prisms for synthesizing optical images. Therefore, the above technology has the following problems: in order to achieve high-resolution color display, not only the structure is complicated, but also the cost is increased. Summary of the invention

[0006] In order to solve the above-mentioned problems, a projection display device according to one embodiment of the present invention includes: a first image light emitting device that emits a first image light; a second image light emitting device that emits a second image light; a synthesis optical system that synthesizes the first image light and the second image light in a state where the second image light is offset relative to the first image light in a first direction and emits the synthesized light; an optical path shifting element that shifts the optical path of the synthesized light emitted from the synthesis optical system; and a display control circuit that controls the first image light emitting device, the second image light emitting device, and the optical path shifting element, wherein one frame period includes a first field period and a second field period, and during the first field period, the display control circuit supplies data signals corresponding to grayscale levels specified by image pixel data arranged in a matrix, data signals of image pixels that are odd-numbered in a second direction intersecting the first direction of the image pixel data and arranged along the first direction to the first image light emitting device. The display control circuit controls the optical path shifting element to set the optical path to a reference position. During the second field, the display control circuit supplies the data signals of the image pixels that are the even-numbered pixels in the second direction of the image pixel data and are arranged along the first direction to the first image light emitting device, and supplies the data signals of the image pixels that are the odd-numbered pixels in the second direction of the image pixel data and are arranged in the first direction to the second image light emitting device. The display control circuit controls the optical path shifting element to shift the optical path along a second direction intersecting the first direction. The first image light emitting device emits the first image light based on the supplied data signal, and the second image light emitting device emits the second image light based on the supplied data signal. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 It is a diagram showing a projection type display device according to the first embodiment.

[0008] Figure 2 It is a block diagram showing the structure of a projection type display device.

[0009] Figure 3 This is a diagram showing the arrangement of image pixels in a projection display device.

[0010] Figure 4 It is a diagram showing the arrangement of panel pixels in a projection type display device.

[0011] Figure 5It is a perspective view showing the structure of a liquid crystal panel in a projection type display device.

[0012] Figure 6 is a cross-sectional view showing the structure of a liquid crystal panel.

[0013] Figure 7 is a block diagram showing the electrical structure of a liquid crystal panel.

[0014] Figure 8 A diagram showing the structure of a pixel circuit in a liquid crystal panel.

[0015] Fig. 9 This is a diagram for explaining the operation of one frame period in the projection type display device.

[0016] Fig.10 It is a diagram for explaining a writing operation in a liquid crystal panel.

[0017] Fig.11 This is a diagram showing the relationship between image pixels, panel pixels, and projection positions within one frame period.

[0018] Fig.12 It is a diagram showing the arrangement of panel pixels in the projection display device according to the second embodiment.

[0019] Fig.13 This is a diagram for explaining the operation of one frame period in the projection type display device.

[0020] Fig.14 This is a diagram showing the relationship between image pixels, panel pixels, and projection positions within one frame period.

[0021] Fig.15 It is a diagram for explaining the operation in one frame period in the projection display device according to the third embodiment.

[0022] Fig.16 This is a diagram for explaining the operation in one frame period in the projection type display device according to another example of the third embodiment.

[0023] Fig.17 It is a diagram showing a projection type display device of an application example.

[0024] Description of symbols

[0025] 1: projection display device; 100a, 100b: liquid crystal panel; 110: pixel circuit; 118: pixel electrode; 120: liquid crystal element; 20: display control circuit; 21: processing circuit; 22a, 22b: conversion circuit; 180: prism; 190: optical path shift element. DETAILED DESCRIPTION

[0026] Hereinafter, the projection display device of the embodiment will be described with reference to the accompanying drawings. In addition, in each figure, the size and scale of each part are appropriately different from the actual size and scale. In addition, the embodiment described below is a preferred specific example, and therefore various technically preferred limitations are added, but as long as there is no record of the subject matter of the present disclosure being particularly limited in the following description, the scope of the present disclosure is not limited to these modes.

[0027] Figure 1 The projection display device 1 according to the first embodiment shows an optical structure. The projection display device 1 includes liquid crystal panels 100 a and 100 b , light sources 151 and 152 , polarization optical systems 160 a and 160 b , a prism 180 , an optical path shifting element 190 , and a projection lens 200 .

[0028] The light source 151 includes laser light sources 151R, 151G, and 151B. The laser light source 151R emits light in a red wavelength band, the laser light source 151G emits light in a green wavelength band, and the laser light source 151B emits light in a blue wavelength band.

[0029] The polarization optical system 160a diffuses the emitted light from the laser light sources 151R, 151G, and 151B to form a substantially uniform illumination and substantially parallel light beam, converts the light beam into P polarized light, and emits it to the transmissive liquid crystal panel 100a. In addition, the conversion into P polarized light also includes transmitting the P polarized light. A polarizing plate 171a is provided between the emission surface of the polarization optical system 160a and the incident surface of the liquid crystal panel 100a, and a polarizing plate 172a is provided on the emission surface of the liquid crystal panel 100a.

[0030] In addition, the transmission axis of the polarizing plate 171a is P polarized light, and the transmission axis of the polarizing plate 172a is S polarized light. Therefore, the P polarized component that is not modulated by the liquid crystal panel 100a is blocked by the polarizing plate 172a.

[0031] The light source 152 includes laser light sources 152R, 152G, and 152B similarly to the light source 151. The laser light source 152R emits light in the red wavelength band, the laser light source 152G emits light in the green wavelength band, and the laser light source 152B emits light in the blue wavelength band.

[0032] The polarization optical system 160b diffuses the emitted light from the laser light sources 152R, 152G, and 152B to form a substantially uniform illumination and substantially parallel light beam, converts the light beam into S polarized light, and emits it to the transmissive liquid crystal panel 100b. In addition, converting to S polarized light also includes transmitting the S polarized light. A polarizing plate 171b is provided between the emission surface of the polarization optical system 160b and the incident surface of the liquid crystal panel 100b, and a polarizing plate 172b is provided on the emission surface of the liquid crystal panel 100b.

[0033] In addition, the transmission axis of the polarizing plate 171b is S polarized light, and the transmission axis of the polarizing plate 172b is P polarized light. Therefore, the S polarized component that is not modulated by the liquid crystal panel 100b is blocked by the polarizing plate 172b.

[0034] The liquid crystal panels 100a and 100b have a plurality of pixel circuits as described later. The plurality of pixel circuits each include a liquid crystal element. The liquid crystal element of the liquid crystal panel 100a is driven based on a data signal supplied from a display control circuit, and modulates the incident light according to the voltage of the data signal. Through this modulation, the amount of light transmitted through the polarizing plate 172a changes, that is, the transmittance changes. Therefore, by controlling the modulation performed by the liquid crystal elements based on the data signal, a transmission image is generated in the liquid crystal panel 100a. Similarly, a transmission image is generated in the liquid crystal panel 100b.

[0035] The transmission image of the liquid crystal panel 100a is Figure 1 The transmitted image of the liquid crystal panel 100a is incident on the prism 180 from the 9 o'clock direction, and the transmitted image of the liquid crystal panel 100b is incident on the prism 180 from the 12 o'clock direction. At the bonding surface 182 of the prism 180, the S polarized light in the transmitted image of the liquid crystal panel 100a is transmitted and goes straight, and the P polarized light in the transmitted image of the liquid crystal panel 100b is reflected.

[0036] Therefore, the transmitted image of the liquid crystal panel 100 a and the transmitted image of the liquid crystal panel 100 b are synthesized in the prism 180 , and the synthesized image is emitted in the direction of 3 o'clock. The synthesized image of the prism 180 enters the projection lens 200 via the optical path shifting element 190 .

[0037] The projection lens 200 enlarges and projects the synthetic image that has passed through the optical path shifting element 190 onto the screen Scr.

[0038] The optical path shifting element 190 shifts the optical path of the light emitted from the prism 180 to shift the synthetic image projected onto the screen Scr in the left-right direction or the up-down direction relative to the projection surface.

[0039] In addition, at the joint surface 182 of the prism 180, the transmission image based on the liquid crystal panel 100a is straight, while the transmission image based on the liquid crystal panel 100b is reflected. Therefore, the transmission image based on the liquid crystal panel 100b is generated in a left-right inversion relative to the transmission image based on the liquid crystal panel 100a. In addition, the pixels of the transmission image based on the liquid crystal panel 100a and the transmission image based on the liquid crystal panel 100b are inconsistent with each other, and as described later, they are synthesized in an offset state.

[0040] Figure 21 is a block diagram showing the electrical structure of the projection display device 1. As shown in the figure, the projection display device 1 includes a display control circuit 20 in addition to the liquid crystal panels 100a, 100b, the light sources 151, 152 and the optical path shift element 190 described above.

[0041] The video data Vid_in is supplied from a host device (not shown) or the like in synchronization with a synchronization signal Sync. The video data Vid_in specifies the grayscale level of a pixel in an image constituting a video in a one-frame period, for example, using 8 bits for each RGB.

[0042] In addition, the pixels of the image specified by the image data Vid_in are marked as image pixels, and the data specifying the grayscale level of the image pixels are marked as image pixel data, but sometimes the image pixels and image pixel data are not particularly distinguished. In addition, the pixels of the image before or after synthesis based on the liquid crystal panel 100a or the liquid crystal panel 100b are marked as panel pixels. The position of the panel pixel shifted by the optical path shifting element 190 and projected on the screen Scr is marked as the projection position.

[0043] In the liquid crystal panel 100a and the liquid crystal panel 100b, the panel pixels corresponding to the pixel circuit are arranged in a matrix when viewed from above. In an embodiment, the arrangement of the image pixels specified by the image data Vid_in is twice as long in the vertical direction and twice as long in the horizontal direction as the arrangement of the panel pixels based on the liquid crystal panel 100a or 100b.

[0044] The synchronization signal Sync includes a vertical synchronization signal for instructing the start of vertical scanning of the video data Vid_in, a horizontal synchronization signal for instructing the start of horizontal scanning, and a clock signal indicating the timing of one video pixel in the video data Vid_in.

[0045] The display control circuit 20 includes a processing circuit 21 and conversion circuits 22 a and 22 b .

[0046] The processing circuit 21 controls the conversion circuits 22a, 22b and the liquid crystal panels 100a, 100b in each writing period described later, and controls the light sources 151, 152 and the optical path shift element 190 in each field period described later, based on the synchronization signal Sync. The optical path shift element 190 shifts the projection position in each field period according to the control performed by the processing circuit 21.

[0047] Figure 3 This figure shows a part of the arrangement of image pixels represented by the image data Vid_in extracted.

[0048] In the figure, in order to distinguish the image pixels in the image represented by the image data Vid_in, for convenience, the first row is assigned A1 to A4, the second row is assigned B1 to B4, the third row is assigned C1 to C4, and the fourth row is assigned D1 to D4.

[0049] Return to Figure 2 In the video data Vid_in, the video pixel data specifying the grayscale level of the video pixel to be expressed by the liquid crystal panel 100a is denoted as Va, and the video pixel data specifying the grayscale level of the video pixel to be expressed by the liquid crystal panel 100b is denoted as Vb.

[0050] After temporarily accumulating image pixel data Va for one or more frame periods in the internal buffer, the conversion circuit 22a reads out the image pixel data of the color component corresponding to the writing period, converts it into an analog voltage data signal Vid_a of the polarity corresponding to the writing period, and supplies it to the liquid crystal panel 100a.

[0051] The conversion circuit 22b is the same as the conversion circuit 22a in that the conversion circuit 22b is different from the conversion circuit 22a only in the image pixel data to be converted. That is, after temporarily accumulating the image pixel data Vb, the conversion circuit 22b reads the image pixel data of the color component corresponding to the writing period, converts it into a data signal Vid_b of an analog voltage of a polarity corresponding to the writing period, and supplies it to the liquid crystal panel 100b.

[0052] In addition, which image pixel's grayscale level is designated by the image pixel data Va and Vb will be described later.

[0053] Figure 4 The panel pixels of the liquid crystal panel 100a and the panel pixels of the liquid crystal panel 100b are extracted. Figure 3 The arrangement of image pixels corresponds to the panel pixels shown in the figure.

[0054] In addition, for the convenience of description, the panel pixels of the liquid crystal panel 100 a are marked as panel pixels a, and the panel pixels of the liquid crystal panel 100 b are marked as panel pixels b.

[0055] In the arrangement of the left column, in order to distinguish the panel pixels a, for convenience, a1 and a2 are assigned to the first row, and a3 and a4 are assigned to the second row. In the arrangement of the right column, in order to distinguish the panel pixels b, for convenience, b1 and b2 are assigned to the first row, and b3 and b4 are assigned to the second row.

[0056] As described later, in order to improve the efficiency of light utilization, a microlens is provided for each panel pixel in the liquid crystal panels 100a and 100b. Therefore, the brightness of the panel pixels is not uniform when viewed from above. In fact, it becomes brighter near the center of the panel pixel and becomes darker as it moves from the center to the outside. In the figure, the circle of the panel pixels a and b simply represents the part that becomes brighter than other parts due to the focusing of the microlens. The center of the circle is roughly consistent with the diagonal center of the panel pixel a or the panel pixel b.

[0057] The arrangement of the panel pixel a and the panel pixel b relative to the prism 180 is as follows: Figure 4 The relationship is shown in the lower column of . Specifically, the relationship is as follows: the arrangement of panel pixels b is offset to the right by 0.5 pixels of the panel pixels in the figure relative to the arrangement of panel pixels a. Specifically, the center of panel pixel b1 is located between the center of panel pixel a1 and the center of panel pixel a2, and the center of panel pixel b3 is located between the center of panel pixel a3 and the center of panel pixel a4.

[0058] Next, the liquid crystal panel 100 a and the liquid crystal panel 100 b are described.

[0059] The liquid crystal panel 100a and the liquid crystal panel 100b are different only in the data signals supplied thereto, and have a common structure. Therefore, the liquid crystal panel 100a and the liquid crystal panel 100b are generally described with reference numeral 100 without specifying any one of them.

[0060] Figure 5 is a perspective view showing the liquid crystal panel 100, Figure 6 So Figure 5 A cross-sectional view obtained by cutting along the Hh line in FIG.

[0061] As shown in these figures, in the liquid crystal panel 100, the element substrate 101 provided with the pixel electrode 118 and the counter substrate 102 provided with the common electrode 108 are bonded together by the sealing material 90 with the electrode forming surfaces facing each other while maintaining a certain gap, and the liquid crystal 105 is sealed in the gap.

[0062] As the element substrate 101 and the counter substrate 102, a light-transmitting substrate such as glass or quartz is used. Figure 5 As shown, one side of the element substrate 101 extends from the counter substrate 102. In the extended region, a plurality of terminals 106 are provided along the lateral direction in the figure. One end of an FPC (Flexible Printed Circuits) substrate (not shown) is connected to the plurality of terminals 106. In addition, the other end of the FPC substrate is connected to the display control circuit 20, and the above-mentioned various signals are supplied.

[0063] The pixel electrode 118 is formed on the surface of the element substrate 101 facing the counter substrate 102 by patterning a transparent conductive layer such as ITO (Indium Tin Oxide).

[0064] In addition, although not shown in the figure, in order to efficiently send a large amount of light to the opening portion that becomes the panel pixel, a microlens is provided for each panel pixel on the opposing substrate 102 (or the element substrate 101). With this structure, the light bounced by the light shielding portion is sent to the opening portion of the microlens, thereby improving the efficiency of light utilization. In addition, the reason for providing the light shielding portion is to determine the outer edge of the panel pixel and to prevent light leakage in the transistor.

[0065] Figure 7 2 is a block diagram showing an electrical structure of the liquid crystal panel 100 . In the liquid crystal panel 100 , a scanning line driving circuit 130 and a data line driving circuit 140 are provided around the display region 10 .

[0066] In the display area 10, the pixel circuits 110 are arranged in a matrix. Specifically, in the display area 10, a plurality of scanning lines 12 are arranged to extend in the horizontal direction in the figure, and a plurality of data lines 14 are arranged to extend in the vertical direction and to be electrically insulated from the scanning lines 12. In addition, the pixel circuits 110 are arranged in a matrix corresponding to the intersections of the plurality of scanning lines 12 and the plurality of data lines 14.

[0067] When the number of scan lines 12 is set to m and the number of data lines 14 is set to n, the pixel circuits 110 are arranged in a matrix with m rows in the vertical direction and n columns in the horizontal direction. Both m and n are integers greater than 2. In order to distinguish the rows of the matrix in the scan lines 12 and the pixel circuits 110, they are sometimes referred to as the 1st, 2nd, 3rd, ..., (m-1), and mth rows from the top in the figure. Similarly, in order to distinguish the columns of the matrix in the data lines 14 and the pixel circuits 110, they are sometimes referred to as the 1st, 2nd, 3rd, ..., (n-1), and nth columns from the left in the figure.

[0068] Furthermore, the image pixels are arranged twice as many vertically as the panel pixels and twice as many horizontally, so the image pixels are arranged in (2m) vertical rows and (2n) horizontal columns.

[0069] "Row" and "column" are relative concepts and are in the following relationship: when one of the horizontal (left-right) direction and the vertical (up-down) direction is set as a "row", the other of the horizontal and vertical directions is a "column". However, in this description, for convenience, as described above, the horizontal direction in which the scanning line 12 extends is set as a "row", and the vertical direction in which the data line 14 extends is set as a "column". The same is true for odd-numbered rows and even-numbered rows, odd-numbered columns and even-numbered columns, and they are in the following relationship: when one of the horizontal and vertical directions is set as an odd-numbered row and an even-numbered row, the other of the horizontal and vertical directions is an odd-numbered column and an even-numbered column.

[0070] In order to generally describe the rows of scan lines 12, panel pixels or image pixels, an integer i greater than 1 and less than m is sometimes used. In order to generally describe the columns of data lines 14, panel pixels or image pixels, an integer j greater than 1 and less than n is sometimes used.

[0071] The scanning line driving circuit 130 selects the scanning lines 12 one by one in the order of, for example, the 1st, 2nd, 3rd, ..., mth row according to the control performed by the display control circuit 20, and sets the scanning signal for the selected scanning line 12 to the H level. In addition, the scanning line driving circuit 130 sets the scanning signal for the scanning line 12 other than the selected scanning line 12 to the L level.

[0072] The data line driving circuit 140 outputs the data signal supplied from the corresponding circuit of the conversion circuit 22 a or the conversion circuit 22 b to the pixel circuits 110 located in the 1st to nth columns of the scanning line 12 via the data line 14 while the scanning signal for the scanning line 12 is at H level.

[0073] Figure 8 1 is a diagram showing an equivalent circuit of four pixel circuits 110 in two vertical rows and two horizontal columns corresponding to the intersection of two adjacent scanning lines 12 and two adjacent data lines 14 .

[0074] As shown in the figure, the pixel circuit 110 includes a transistor 116 and a liquid crystal element 120. The transistor 116 is, for example, an n-channel thin film transistor. In the pixel circuit 110, the gate node of the transistor 116 is connected to the scan line 12, the source node of the transistor 116 is connected to the data line 14, and the drain node of the transistor 116 is connected to the pixel electrode 118 which is square in shape when viewed from above.

[0075] The common electrode 108 is provided in common to all pixels so as to face the pixel electrode 118. A voltage LCcom is applied to the common electrode 108. The liquid crystal 105 is sandwiched between the pixel electrode 118 and the common electrode 108 as described above. Therefore, a liquid crystal element 120 in which the liquid crystal 105 is sandwiched between the pixel electrode 118 and the common electrode 108 is formed for each pixel circuit 110.

[0076] In addition, a storage capacitor 109 is provided in parallel with the liquid crystal element 120. One end of the storage capacitor 109 is connected to the pixel electrode 118, and the other end is connected to the capacitor line 107. A temporally constant voltage is applied to the capacitor line 107, for example, a voltage LCcom which is the same as the voltage applied to the common electrode 108. The pixel circuit 110 is arranged in a matrix in the horizontal direction, which is the extension direction of the scanning line 12, and in the vertical direction, which is the extension direction of the data line 14, so the pixel electrodes 118 included in the pixel circuit 110 are also arranged in a matrix in the vertical and horizontal directions.

[0077] In the scanning line 12 whose scanning signal becomes H level, the transistor 116 of the pixel circuit 110 provided corresponding to the scanning line 12 becomes on. By the on-state of the transistor 116, the data line 14 and the pixel electrode 118 are electrically connected, so the data signal supplied to the data line 14 reaches the pixel electrode 118 via the on-state transistor 116. When the scanning line 12 becomes L level, the transistor 116 becomes off, but the voltage of the data signal reaching the pixel electrode 118 is maintained by the capacitive property of the liquid crystal element 120 and the storage capacitor 109.

[0078] As is well known, in the liquid crystal element 120, the orientation of the liquid crystal molecules changes according to the electric field generated by the pixel electrode 118 and the common electrode 108. Therefore, the liquid crystal element 120 has a transmittance corresponding to the effective value of the applied voltage.

[0079] In addition, the area that functions as a panel pixel in the liquid crystal element 120, that is, the area that becomes the transmittance corresponding to the effective value of the voltage, is the area where the pixel electrode 118 overlaps with the common electrode 108 when looking down at the element substrate 101 and the opposing substrate 102. The pixel electrode 118 is square in plan view, and therefore the shape of the panel pixel of the liquid crystal panel 100 is also square.

[0080] In this embodiment, the liquid crystal 105 is of VA (Vertical Alignment) type, which is a normally black mode in which the transmittance is lowest when the voltage applied to the liquid crystal element 120 is zero and the transmittance increases as the applied voltage increases.

[0081] The writing operation of supplying the data signal to the pixel electrode 118 of the liquid crystal element 120 is performed in the order of the 1st, 2nd, 3rd, ..., mth row. Thus, the liquid crystal elements 120 of the pixel circuit 110 arranged in m rows × n columns respectively maintain a voltage corresponding to the data signal, and each liquid crystal element 120 becomes a target transmittance, and a transmission image is generated by the liquid crystal elements 120 arranged in m rows × n columns.

[0082] In addition, applying a DC voltage to the liquid crystal element 120 will cause the liquid crystal 105 to deteriorate, and therefore, a positive voltage and a negative voltage are alternately applied to the pixel electrode 118 of the liquid crystal element 120. That is, the liquid crystal element 120 is driven by AC. The reference of the polarity is generally the voltage LCcom applied to the common electrode 108. The case where a data signal higher than the voltage LCcom is applied to the pixel electrode 118 is called positive polarity writing, and the case where a data signal lower than the voltage LCcom is applied to the pixel electrode 118 is called negative polarity writing. In addition, considering the pull-down (push down) of the transistor 116, the reference of the polarity is sometimes based on a voltage different from the voltage LCcom.

[0083] As described above, when the synthesis is performed using the prism 180, the following relationship is achieved: the arrangement of the panel pixels b is offset to the right by 0.5 pixels of the panel pixels relative to the arrangement of the panel pixels a. Therefore, in the synthetic image based on the transmission images of the liquid crystal panel 100a and the liquid crystal panel 100b, the panel pixels are arranged in m rows (2n) columns.

[0084] The image pixels of the image specified by the image data Vid_in are arranged in (2m) rows×(2n) columns, so the resolution in the vertical direction (column direction) is insufficient in the synthesized image.

[0085] Therefore, the following describes an operation for doubling the vertical resolution of the synthetic image for visual confirmation.

[0086] Fig. 9 These are diagrams for explaining the operation of the projection display device 1 according to the first embodiment.

[0087] As shown in the figure, in the present embodiment, one frame period (1F) is divided into an odd field period (Odd-f) which is earlier in time and an even field period (Even-f) which is later in time. One frame period (1F) refers to a period during which one frame of an image represented by the video data Vid_in is supplied. When the frequency of the vertical synchronization signal included in the synchronization signal Sync is 60 Hz, one frame period is 16.7 milliseconds which is one cycle.

[0088] In the first embodiment, the odd field period (Odd-f) refers to the period during which the panel pixel a of the liquid crystal panel 100a represents the image pixels of odd rows and odd columns, and the panel pixel b of the liquid crystal panel 100b represents the image pixels of odd rows and even columns. That is, the odd field period (Odd-f) refers to the period during which the image pixels of odd rows are represented by the composite image of the panel pixel a and the panel pixel b.

[0089] In addition, during the odd field period (Odd-f), the data signal Vid_a supplied by the conversion circuit 22a to the liquid crystal panel 100a corresponds to the grayscale level of the image pixels located in the odd rows and odd columns. In addition, during the odd field period (Odd-f), the data signal Vid_b supplied by the conversion circuit 22b to the liquid crystal panel 100b corresponds to the grayscale level of the image pixels located in the odd rows and even columns.

[0090] The even field period (Even-f) refers to the period during which the panel pixel a of the liquid crystal panel 100a represents the image pixels of the even rows and odd columns, and the panel pixel b of the liquid crystal panel 100b represents the image pixels of the even rows and even columns. That is, the even field period (Even-f) refers to the period during which the image pixels of the even rows are represented by the composite image of the panel pixel a and the panel pixel b.

[0091] Furthermore, during the even field period (Even-f), the data signal Vid_a supplied by the conversion circuit 22a to the liquid crystal panel 100a corresponds to the grayscale level of the image pixels located in the even rows and odd columns. Furthermore, during the even field period (Even-f), the data signal Vid_b supplied by the conversion circuit 22b to the liquid crystal panel 100b corresponds to the grayscale level of the image pixels located in the even rows and even columns.

[0092] Specifically, in the first embodiment, during an odd field (Odd-f), the panel pixel a of the i row and j column represents the image pixel of the (2i-1) row and (2j-1) column, and the panel pixel b of the i row and j column represents the image pixel of the (2i-1) row and (2j) column.

[0093] In addition, during the even field period (Even-f), the panel pixel a in the i row and j column represents the image pixel in the (2i) row and (2j-1) column, and the panel pixel b in the i row and j column represents the image pixel in the (2i) row and (2j) column.

[0094] Furthermore, (2i-1) and (2j-1) are both odd numbers, and (2i) and (2j) are both even numbers.

[0095] When a panel pixel “represents” a certain image pixel, it means that the liquid crystal element 120 of the panel pixel is in a state of transmittance corresponding to the grayscale level (image pixel data) of the image pixel.

[0096] In addition, if one frame period (1F) is 16.7 milliseconds, the odd-numbered field period (Odd-f) and the even-numbered field period (Even-f) are half of that, that is, 8.33 milliseconds.

[0097] In the first embodiment, the image pixel data Va supplied to the conversion circuit 22a specifies the grayscale level of the image pixels located in the odd rows and odd columns during the odd field period (Odd-f), and specifies the grayscale level of the image pixels located in the even rows and odd columns during the even field period (Even-f). The image pixel data Vb supplied to the conversion circuit 22b specifies the grayscale level of the image pixels located in the odd rows and even columns during the odd field period (Odd-f), and specifies the grayscale level of the image pixels located in the even rows and even columns during the even field period (Even-f).

[0098] The odd-numbered field period (Odd-f) is further divided into three unit periods, and in each unit period, one panel pixel individually represents the RGB components of the corresponding image pixel. That is, in the three unit periods of the odd-numbered field period (Odd-f), one panel pixel represents the RGB components of the image pixel in sequence according to color, that is, color is represented in a time-division manner.

[0099] In addition, the period during which the panel pixels express the R component of the image pixels in the odd rows within the odd field period (Odd-f) is set to OfL-R, the period during which the panel pixels express the G component is set to OfL-G, and the period during which the panel pixels express the B component is set to OfL-B.

[0100] Regarding the even field period (Even-f), it is also divided into three unit periods, namely, the unit period (EfL-R) in which the panel pixels represent the R component of the image pixels in the even rows, the unit period (EfL-G) in which the panel pixels represent the G component, and the unit period (EfL-B) in which the panel pixels represent the B component.

[0101] In addition, if the odd field period (Odd-f) and the even field period (Even-f) are 8.33 milliseconds, the unit period (OfL-R, OfL-G, OfL-B, EfL-R, EfL-G, EfL-B) is 1 / 3, that is, 2.78 milliseconds.

[0102] In addition, the unit period (OfL-R, OfL-G, OfL-B, EfL-R, EfL-G, EfL-B) is also divided into a writing period (+) for writing a positive polarity data signal and a writing period (-) for writing a negative polarity data signal.

[0103] In the first embodiment, the processing circuit 21 controls the optical path shift element 190 as follows. If the projection position during the odd field period (Odd-f) is set as the reference position, the processing circuit 21 shifts the projection position downward by 0.5 pixels of the panel pixel during the even field period (Even-f). When the even field period (Even-f) ends, the processing circuit 21 controls the optical path shift element 190 to shift the projection position upward by 0.5 pixels of the panel pixel during the odd field period and return to the reference position.

[0104] In addition, the bottom refers to the vertical scanning direction, that is, the direction of sequentially selecting the scanning line 12. Figure 4 In the case of, for example, the direction from panel pixel a1 to a3. Fig. 9 When the control signal for the optical path shift element 190 is at the H level, the projection position becomes the reference position, and when the control signal for the optical path shift element 190 is at the L level, the projection position is shifted downward from the reference position by 0.5 pixels of the panel pixels.

[0105] The processing circuit 21 controls the light sources 151 and 152 in the following manner.

[0106] In detail, first, the processing circuit 21 controls the laser light source 151R and the laser light source 152R to be in the on state, and controls the other laser light sources to be in the off state during the unit period (OfL-R) within the odd field period (Odd-f) and the unit period (EfL-R) within the even field period (Even-f).

[0107] In addition, the on state of the laser light source refers to a state in which the laser light source emits light, and the off state of the laser light source refers to a state in which the laser light source does not emit light.

[0108] Second, the processing circuit 21 controls the laser light source 151G and the laser light source 152G to be in the on state, and controls the other laser light sources to be in the off state, during the unit period (OfL-G) within the odd field period (Odd-f) and the unit period (EfL-G) within the even field period (Even-f).

[0109] Third, the processing circuit 21 controls the laser light source 151B and the laser light source 152B to be in the on state, and controls the other laser light sources to be in the off state, during the unit period (OfL-B) within the odd field period (Odd-f) and the unit period (EfL-B) within the even field period (Even-f).

[0110] Fig.10The figure shows the time transition of the scan line 12 selected in the liquid crystal panel 100a and the liquid crystal panel 100b when the number of rows of the scan line 12, i.e., the 1st to the mth row, is set as the vertical axis and the elapsed time is set as the horizontal axis. In addition, in the figure, the positive polarity writing period (+) within the unit period (OfL-R) is taken as an example.

[0111] When the selection of the scanning line 12 is indicated by a thick black line, since the scanning line 12 is exclusively selected row by row in each horizontal scanning period (1H), the selected scanning line 12 sequentially shifts from the 1st row to the mth row as time passes.

[0112] In addition, the positive writing period (+) in the unit period (OfL-R) is followed by the negative writing period (-). Similarly, in the negative writing period (-), the scanning line 12 is exclusively selected in each horizontal scanning period (1H) from the 1st row to the mth row.

[0113] In addition, here, the unit period (OfL-R) within the odd field period (Odd-f) is explained, but in the unit period (OfL-G, OfL-B) and the each writing period of the unit period (EfL-R, EfL-G, EfL-B) within the even field period (Even-f), the scanning line 12 is exclusively selected in each horizontal scanning period (1H) from the 1st row to the mth row.

[0114] Fig.11 1 is a diagram showing which image pixel is represented at which projection position by panel pixel a and panel pixel b in the first embodiment. Fig.11 It is shown Figure 4 The 4 panel pixels a1 to a4 in the upper left column and Figure 4 In the upper right column of the figure, the four panel pixels b1 to b4 are projected at which positions during the odd-numbered field period (Odd-f) and the even-numbered field period (Even-f). Figure 3 Figure 2. Pixels of the image shown.

[0115] As shown in the figure, during the odd field period (Odd-f), the panel pixels a1 to a4 sequentially represent the image pixels A1, A3, C1 and C3 of the odd rows and odd columns to which the shadows are applied. In other words, the panel pixels a1 to a4 are sequentially supplied with the data signals of the R component, G component and B component of the image pixels A1, A3, C1 and C3 within the unit period (OfL-R, OfL-G, OfL-B) of the odd field period (Odd-f), and sequentially represent the R, G, B components.

[0116] In addition, during the odd field period (Odd-f), the panel pixels b1 to b4 sequentially represent the image pixels A2, A4, C2, and C4 in odd rows and even columns to which shadows are applied. In other words, the panel pixels b1 to b4 are sequentially supplied with the data signals of the R component, G component, and B component of the image pixels A2, A4, C2, and C4 within the unit period (OfL-R, OfL-G, OfL-B) of the odd field period (Odd-f), and sequentially represent the R, G, and B components.

[0117] In addition, an arrow pointing upward in a panel pixel in an odd-numbered field period (Odd-f) indicates a shift direction from a projection position in the immediately preceding even-numbered field period (Even-f).

[0118] The processing circuit 21 controls the laser light source 151R and the laser light source 152R to be turned on during the unit period (OfL-R) within the odd field period (Odd-f). Therefore, during the unit period (OfL-R), the R components of the image pixels A1, A3, C1, C3, A2, A4, C2, and C4 represented by the panel pixels a1 to a4 and the panel pixels b1 to b4 are visually recognized by the user. Next, the processing circuit 21 controls the laser light source 151G and the laser light source 152G to be turned on during the unit period (OfL-G). Therefore, the G components of the image pixels A1, A3, C1, C3, A2, A4, C2, and C4 represented by the panel pixels a1 to a4 and the panel pixels b1 to b4 are visually recognized by the user.

[0119] Then, the processing circuit 21 controls the laser light source 151B and the laser light source 152B to be turned on during the unit period (OfL-B). Therefore, the B components of the image pixels A1, A3, C1, C3, A2, A4, C2, and C4 represented by the panel pixels a1 to a4 and the panel pixels b1 to b4 are visually recognized by the user.

[0120] In this way, during the odd-numbered field period (Odd-f), the RGB components of the image pixels in the odd-numbered rows among the image pixels are sequentially displayed in color, and as a result, the user visually recognizes them in color.

[0121] When the odd field period (Odd-f) ends, it becomes the even field period (Even-f). The processing circuit 21 controls the optical path shift element 190 to shift the projection position from the reference position to the bottom of the figure by 0.5 pixels of the panel pixel.

[0122] During the even field period (Even-f), the panel pixels a1 to a4 sequentially represent the image pixels B1, B3, D1 and D3 of the even rows and odd columns to which the shadows are applied. In other words, the panel pixels a1 to a4 are sequentially supplied with the data signals of the R component, G component and B component of the image pixels B1, B3, D1 and D3 within the unit period (EfL-R, EfL-G, EfL-B) of the even field period (Even-f), and sequentially represent the R, G, B components.

[0123] In addition, during the even field period (Even-f), the panel pixels b1 to b4 sequentially represent the image pixels B2, B4, D2, and D4 of the even rows and even columns to which the shadows are applied. In other words, the panel pixels b1 to b4 are sequentially supplied with the data signals of the R component, G component, and B component of the image pixels B2, B4, D2, and D4 within the unit periods (EfL-R, EfL-G, and EfL-B) of the even field period (Even-f), and sequentially represent the R, G, and B components.

[0124] In addition, the arrow pointing downward in the panel pixel in the even-numbered field period (Even-f) indicates the shift direction from the projection position in the immediately preceding odd-numbered field period (Odd-f).

[0125] The processing circuit 21 controls the laser light source 151R and the laser light source 152R to be turned on during the unit period (EfL-R) within the even field period (Even-f). Therefore, during the unit period (EfL-R), the R components of the image pixels B1, B3, D1, D3, B2, B4, D2, and D4 represented by the panel pixels a1 to a4 and the panel pixels b1 to b4 are visually recognized by the user.

[0126] Next, the processing circuit 21 controls the laser light source 151G and the laser light source 152G to be turned on during the unit period (EfL-G). Therefore, the G components of the image pixels B1, B3, D1, D3, B2, B4, D2, and D4 represented by the panel pixels a1 to a4 and the panel pixels b1 to b4 are visually recognized by the user.

[0127] Then, the processing circuit 21 controls the laser light source 151B and the laser light source 152B to be turned on during the unit period (EfL-B). Therefore, the B components of the image pixels B1, B3, D1, D3, B2, B4, D2, and D4 represented by the panel pixels a1 to a4 and the panel pixels b1 to b4 are visually recognized by the user.

[0128] In this way, during the even-numbered field period (Even-f), the RGB components of the image pixels in the even-numbered rows among the image pixels are sequentially displayed in color, and as a result, the user can visually recognize them in color.

[0129] Therefore, during the odd-numbered field period (Odd-f) and the even-numbered field period (Even-f) as a whole, the image pixels arranged in (2m) rows × (2n) columns are visually recognized by the user in color through the composite image and shift of the liquid crystal panels 100a and 100b.

[0130] According to the first embodiment, the liquid crystal panels 100a and 100b are configured to be offset by 0.5 pixels in the vertical direction, so that the user can visually recognize a color image having a resolution four times that of the liquid crystal panels 100a and 100b.

[0131] In other words, in this embodiment, the liquid crystal panels 100a and 100b only need to have a resolution of 1 / 4 of the resolution of the image to be visually recognized, and thus can be configured at a lower cost than when using a liquid crystal panel with the same resolution as the projected image.

[0132] In the first embodiment, the arrangement of the panel pixels b in the liquid crystal panel 100 b is shifted to the right by 0.5 pixels with respect to the arrangement of the panel pixels a in the liquid crystal panel 100 a , but the present invention is not limited to this relationship.

[0133] Therefore, a second embodiment which is different from the first embodiment in terms of the positional relationship between the liquid crystal panels 100 a and 100 b will be described.

[0134] Fig.12 In the second embodiment, the panel pixel a of the liquid crystal panel 100a and the panel pixel b of the liquid crystal panel 100b are extracted. Figure 3 The liquid crystal panel 100a and the liquid crystal panel 100b are the same as those in the first embodiment, but the arrangement of the liquid crystal panel 100a and the liquid crystal panel 100b relative to the prism 180 is changed to Fig.12 The relationship is shown in the lower column.

[0135] Specifically, the arrangement of panel pixels b is shifted downward by 0.5 pixels relative to the arrangement of panel pixels a. Specifically, panel pixel b1 is located between panel pixels a1 and a3, and panel pixel b2 is located between panel pixels a2 and a4.

[0136] Fig.13 It is a diagram for explaining the operation of the projection display device 1 according to the second embodiment.

[0137] In the second embodiment, as in the first embodiment, one frame period (1F) is divided into an odd field period (Odd-f) earlier in time and an even field period (Even-f) later in time, which is the same as the first embodiment, but it is different from the first embodiment in that odd columns of image pixels are displayed during the odd field period (Odd-f) and even columns of image pixels are displayed during the even field period (Even-f).

[0138] Specifically, in the second embodiment, the odd field period (Odd-f) refers to the period during which the panel pixel a of the liquid crystal panel 100a represents the image pixels of the odd rows and odd columns, and the panel pixel b of the liquid crystal panel 100b represents the image pixels of the even rows and odd columns. The even field period (Even-f) refers to the period during which the panel pixel a represents the image pixels of the odd rows and even columns, and the panel pixel b represents the image pixels of the even rows and even columns.

[0139] Specifically, in the second embodiment, during an odd field period (Odd-f), the panel pixel a in the i row and j column represents the image pixel in the (2i-1) row and (2j-1) column, and the panel pixel b in the i row and j column represents the image pixel in the (2i) row and (2j-1) column. In addition, during an even field period (Even-f), the panel pixel a in the i row and j column represents the image pixel in the (2i-1) row and (2j) column, and the panel pixel b in the i row and j column represents the image pixel in the (2i) row and (2j) column.

[0140] In the second embodiment, the conversion circuits 22a and 22b are different from the first embodiment only in the image pixel data to be converted, and the rest is the same as the first embodiment. That is, in the second embodiment, the image pixel data Va supplied to the conversion circuit 22a specifies the grayscale level of the image pixels located in the odd rows and odd columns during the odd field period (Odd-f), and specifies the grayscale level of the image pixels located in the odd rows and even columns during the even field period (Even-f). The image pixel data Vb supplied to the conversion circuit 22b specifies the grayscale level of the image pixels located in the even rows and odd columns during the odd field period (Odd-f), and specifies the grayscale level of the image pixels located in the even rows and even columns during the even field period (Even-f).

[0141] In addition, in the second embodiment, the following aspects are the same as the first embodiment, namely: the odd-numbered field period (Odd-f) is divided into three unit periods, and in each unit period, one panel pixel individually represents the RGB components of the image pixel represented by the panel pixel; and the even-numbered field period (Even-f) is divided into three unit periods, and in each unit period, one panel pixel individually represents the RGB components of the image pixel represented by the panel pixel.

[0142] In the second embodiment, the unit period for representing the R component of the image pixels in the odd columns within the odd field period (Odd-f) of the panel pixels is set to OfC-R, the unit period for representing the G component is set to OfC-G, and the unit period for representing the B component is set to OfC-B. The three unit periods (OfC-R, OfC-G, OfC-B) are respectively divided into a writing period (+) for writing a data signal of a positive polarity and a writing period (-) for writing a data signal of a negative polarity.

[0143] Regarding the even field period (Even-f), it is also divided into three unit periods, namely, the unit period (EfC-R) for the panel pixels to express the R component of the image pixels in the even columns, the unit period (EfC-G) for expressing the G component, and the unit period (EfC-B) for expressing the B component. Moreover, the three unit periods are respectively divided into a writing period (+) for writing a positive polarity data signal and a writing period (-) for writing a negative polarity data signal.

[0144] In the second embodiment, the processing circuit 21 controls the optical path shift element 190 as follows. The projection position during the odd field period (Odd-f) is set as the reference position. The processing circuit 21 shifts the projection position to the right by 0.5 pixels of the panel pixel during the even field period (Even-f). When the even field period (Even-f) ends, the processing circuit 21 controls the optical path shift element 190 to shift the projection position to the left by 0.5 pixels of the panel pixel during the odd field period (Odd-f) and return to the reference position.

[0145] In addition, the right side is the horizontal scanning direction. Fig.12 In the case of, for example, the direction from panel pixel a1 to panel pixel a2. Fig.13 When the control signal for the optical path shift element 190 is at the H level, the projection position becomes the reference position, and when the control signal for the optical path shift element 190 is at the L level, the projection position is shifted to the right by 0.5 panel pixels from the reference position.

[0146] In the second embodiment, the processing circuit 21 controls the light source 151 and the light source 152 in the same manner as in the first embodiment.

[0147] In detail, first, the processing circuit 21 controls the laser light source 151R and the laser light source 152R to be in the on state, and controls the other laser light sources to be in the off state during the unit period (OfC-R) of the odd field period (Odd-f) and the unit period (EfC-R) of the even field period (Even-f).

[0148] Second, the processing circuit 21 controls the laser light source 151G and the laser light source 152G to be in the on state, and controls the other laser light sources to be in the off state during the unit period (OfC-G) of the odd field period (Odd-f) and the unit period (EfC-G) of the even field period (Even-f).

[0149] Third, the processing circuit 21 controls the laser light source 151B and the laser light source 152B to be in the on state, and controls the other laser light sources to be in the off state, during the unit period (OfC-B) within the odd field period (Odd-f) and the unit period (EfC-B) within the even field period (Even-f).

[0150] Fig.14 : is a diagram showing which image pixel is represented at which projection position by panel pixel a and panel pixel b in the second embodiment. Fig.14 It is shown Fig.12 The 4 panel pixels a1 to a4 in the upper left column and Fig.12 In the upper right column of the figure, the four panel pixels b1 to b4 are projected at which positions during the odd-numbered field period (Odd-f) and the even-numbered field period (Even-f). Figure 3 Figure 2. Pixels of the image shown.

[0151] like Fig.14 As shown, during the odd field period (Odd-f), the panel pixels a1 to a4 sequentially display the R component, G component and B component of the image pixels A1, A3, C1 and C3 in the odd rows and columns to which shadows are applied in the unit period (OfC-R, OfC-G, OfC-B).

[0152] In addition, during the odd field period (Odd-f), the panel pixels b1 to b4 sequentially display the R component, G component and B component of the image pixels B1, B3, D1 and D3 in the even rows and odd columns to which shadows are applied in the unit period (OfC-R, OfC-G, OfC-B).

[0153] In addition, an arrow pointing leftward in a panel pixel in an odd-numbered field period (Odd-f) indicates a shift direction from a projection position in the immediately preceding even-numbered field period (Even-f).

[0154] The processing circuit 21 controls the laser light source 151R and the laser light source 152R to be turned on during the unit period (OfC-R) within the odd field period (Odd-f). Therefore, during the unit period (OfC-R), the R components of the image pixels A1, A3, C1, C3, B1, B3, D1, and D3 represented by the panel pixels a1 to a4 and the panel pixels b1 to b4 are visually recognized by the user. Next, the processing circuit 21 controls the laser light source 151G and the laser light source 152G to be turned on during the unit period (OfC-G) within the odd field period (Odd-f). Therefore, during the unit period (OfC-G), the G components of the image pixels A1, A3, C1, C3, B1, B3, D1, and D3 represented by the panel pixels a1 to a4 and the panel pixels b1 to b4 are visually recognized by the user.

[0155] Then, the processing circuit 21 controls the laser light source 151B and the laser light source 152B to be turned on during the unit period (OfC-B), so that the B components of the image pixels A1, A3, C1, C3, B1, B3, D1, and D3 represented by the panel pixels a1 to a4 and the panel pixels b1 to b4 are visually recognized by the user.

[0156] In this way, during the odd-numbered field period (Odd-f), the RGB components of the image pixels in the odd-numbered columns among the image pixels are sequentially displayed in color, and as a result, the user visually recognizes them in color.

[0157] When the odd field period (Odd-f) ends, it becomes the even field period (Even-f). The processing circuit 21 controls the optical path shift element 190 to shift the projection position from the reference position to the right by 0.5 pixels of the panel pixel in the figure.

[0158] During the unit periods (EfC-R, EfC-G, EfC-B) within the even field period (Even-f), the panel pixels a1 to a4 respectively represent the R component, G component and B component of the image pixels A2, A4, C2 and C4 in the odd rows and even columns to which shadows are applied.

[0159] In addition, during the unit period (EfC-R, EfC-G, EfC-B), panel pixels b1 to b4 sequentially represent the R component, G component, and B component of image pixels B2, B4, D2, and D4 in even rows and even columns to which shadows are applied.

[0160] In addition, an arrow pointing rightward in a panel pixel in an even-numbered field period (Even-f) indicates a shift direction from a projection position in the immediately preceding odd-numbered field period (Odd-f).

[0161] The processing circuit 21 controls the laser light source 151R and the laser light source 152R to be turned on during the unit period (EfC-R) of the even field period (Even-f). As a result, the R components of the image pixels A2, A4, C2, C4, B2, B4, D2, and D4 represented by the panel pixels a1 to a4 and the panel pixels b1 to b4 are visually recognized by the user.

[0162] Next, the processing circuit 21 controls the laser light source 151G and the laser light source 152G to be turned on during the unit period (EfC-G). As a result, the G components of the image pixels A2, A4, C2, C4, B2, B4, D2, and D4 represented by the panel pixels a1 to a4 and the panel pixels b1 to b4 are visually recognized by the user.

[0163] Then, the processing circuit 21 controls the laser light source 151B and the laser light source 152B to be turned on during the unit period (EfC-B). As a result, the B components of the image pixels A2, A4, C2, C4, B2, B4, D2, and D4 represented by the panel pixels a1 to a4 and the panel pixels b1 to b4 are visually recognized by the user.

[0164] In this way, during the even-numbered field period (Even-f), the RGB components of the image pixels in the even-numbered columns among the image pixels are sequentially displayed in color, and as a result, the user visually recognizes them in color.

[0165] Therefore, during the odd-numbered field period (Odd-f) and the even-numbered field period (Even-f) as a whole, the image pixels arranged in (2m) rows × (2n) columns are visually recognized by the user in color through the composite image and shift of the liquid crystal panels 100a and 100b.

[0166] According to the second embodiment, similarly to the first embodiment, the liquid crystal panels 100a and 100b are shifted by 0.5 pixels of the panel pixels, so that the user can visually recognize a color image having a resolution four times that of the liquid crystal panels 100a and 100b.

[0167] In other words, in this embodiment, the liquid crystal panels 100a and 100b only need to have a resolution of 1 / 4 of the resolution of the image to be visually recognized, and thus can be configured at a lower cost than when using a liquid crystal panel with the same resolution as the projected image.

[0168] In the first embodiment or the second embodiment, color image pixels are sequentially displayed in color, so color breakup is easily visually recognized. Color breakup is also called color breakup.

[0169] Since color breakup is easily visually recognized at the timing of color switching, it can be said that visual recognition of color breakup is suppressed by shortening the color switching interval or reducing the number of color switching times per unit time.

[0170] In the first embodiment or the second embodiment, the unit period given to represent each component of the three primary colors is 2.78 milliseconds. In a general liquid crystal panel, it is difficult to drive the liquid crystal panel with a period shorter than the unit period, that is, it is difficult to drive the liquid crystal panel with a frequency higher than the frequency corresponding to the length of the period.

[0171] On the other hand, in order for a user (human) to perceive colors, at least three primary colors are required. Therefore, as a period for perceiving colors (field period referred to in the embodiment), at least three unit periods are required for one panel.

[0172] In the first embodiment or the second embodiment, the field period is divided into three unit periods, but the number of panels is 2. Using this point, a third embodiment in which the visibility of color breakup is reduced will be described.

[0173] The third embodiment differs from the first embodiment in the order of colors expressed in three unit periods, the operation of the liquid crystal panel 100 b, and the operation of the light source 152 . Therefore, the following mainly describes these differences.

[0174] Fig.15 This is a diagram for explaining the operation of the projection display device 1 according to the third embodiment. In the third embodiment, the first unit period obtained by dividing the odd field period (Odd-f) into three is the unit period (OfL-R / G), and the second unit period is the unit period (OfL-G / R). In addition, the third unit period in the odd field period (Odd-f) is the unit period (OfL-B).

[0175] In addition, the first unit period obtained by dividing the even field period (Even-f) into three is the unit period (EfL-R / G), and the second unit period (EfL-G / R). In addition, the third unit period in the even field period (Even-f) is the unit period (EfL-B).

[0176] The unit period (OfL-R / G) is a period during which the panel pixel a of the liquid crystal panel 100a represents the R component of the image pixel in odd rows and odd columns, and a period during which the panel pixel b of the liquid crystal panel 100b represents the G component of the image pixel in odd rows and even columns.

[0177] The unit period (OfL-G / R) is a period during which panel pixel a represents the G component of the image pixel in odd rows and odd columns, and a period during which panel pixel b represents the R component of the image pixel in odd rows and even columns.

[0178] In addition, the unit period (OfL-B) is a period during which panel pixel a represents the B component of the image pixel in odd rows and odd columns, and a period during which panel pixel b represents the B component of the image pixel in odd rows and even columns.

[0179] The unit period (EfL-R / G) is a period during which panel pixel a represents the R component of the image pixel in the even row and odd column, and a period during which panel pixel b represents the G component of the image pixel in the even row and even column.

[0180] The unit period (EfL-G / R) is a period during which panel pixel a represents the G component of the image pixel in the even row and odd column, and a period during which panel pixel b represents the R component of the image pixel in the even row and even column.

[0181] In addition, the unit period (EfL-B) is a period during which panel pixel a represents the B component of image pixels in even rows and odd columns, and a period during which panel pixel b represents the B component of image pixels in even rows and even columns.

[0182] In the third embodiment, the processing circuit 21 controls the light source 151 in the same manner as in the first embodiment, but controls the light source 152 in the following manner differently from the first embodiment. Specifically, the processing circuit 21 sequentially controls the laser light sources 151R, 151G, and 151B to be turned on for the light source 151, but sequentially controls the laser light sources 151G, 151R, and 151B to be turned on for the light source 152, during each unit period of the odd field period (Odd-f) and the even field period (Even-f).

[0183] Thus, in the third embodiment, the liquid crystal panel 100b of the first embodiment is in the following relationship: the time sequence of the unit period (OfL-R) and the unit period (OfL-G) is swapped, and the time sequence of the unit period (EfL-R) and the unit period (EfL-G) is swapped.

[0184] In the third embodiment, during the unit period (OfL-R / G), the liquid crystal panel 100a represents the R component, the liquid crystal panel 100b represents the G component, and the laser light source 151R and the laser light source 152G are turned on. Therefore, the R component of the image pixel represented by the panel pixel a and the G component of the image pixel represented by the panel pixel b are synthesized, and the Y (yellow) component is visually recognized by the user.

[0185] In the unit period (OfL-G / R), the liquid crystal panel 100a represents the G component and the liquid crystal panel 100b represents the R component, and thus similarly, the user visually recognizes the Y component obtained by combining the two components.

[0186] Therefore, in the third embodiment, the structure is as follows: the three unit periods (OfL-R / G, OfL-G / R, OfL-B) in the odd field period (Odd-f) are switched in the order of YYB from a synthetic point of view, and the three unit periods (EfL-R / G, EfL-G / R, EfL-B) in the even field period (Even-f) are also switched in the order of YYB.

[0187] Therefore, according to the third embodiment, the number of times of color switching is reduced in each field period compared to the configuration of switching in the order of RGB as in the first embodiment, and thus visual confirmation of color breakup can be reduced.

[0188] In addition, in the third embodiment, the following relationship is set relative to the first embodiment, that is, the time order of the unit period (OfL-R) and the unit period (OfL-G) of the liquid crystal panel 100b is swapped and the time order of the unit period (EfL-R) and the unit period (EfL-G) is swapped, but it is not limited to this.

[0189] For example, you can also Fig.16 As shown, the following relationship is set relative to the second embodiment, that is, the time order of the unit period (OfC-R) and the unit period (OfC-G) of the liquid crystal panel 100b is swapped and the time order of the unit period (EfC-R) and the unit period (EfC-G) is swapped. In detail, in the second embodiment, the first of the three unit periods within the odd field period (Odd-f) becomes the unit period (OfC-R / G), the second becomes the unit period (OfC-G / R), and the third becomes the unit period (OfC-B). In addition, the first of the three unit periods within the even field period (Even-f) becomes the unit period (EfC-R / G), the second becomes the unit period (EfC-G / R), and the third becomes the unit period (EfC-B).

[0190] The unit period (OfC-R / G) is a period during which the panel pixel a of the liquid crystal panel 100a represents the R component of the image pixel of the odd row and odd column, and the panel pixel b of the liquid crystal panel 100b represents the G component of the image pixel of the even row and odd column. The unit period (OfC-G / R) is a period during which the panel pixel a represents the G component of the image pixel of the odd row and odd column, and the panel pixel b represents the R component of the image pixel of the even row and odd column.

[0191] In addition, the unit period (OfC-B) is a period during which panel pixel a represents the B component of the image pixel in odd rows and odd columns, and a period during which panel pixel b represents the B component of the image pixel in even rows and odd columns.

[0192] In addition, the unit period (EfC-R / G) is a period during which panel pixel a represents the R component of the image pixel in the odd row and even column, and a period during which panel pixel b represents the G component of the image pixel in the even row and even column. The unit period (EfC-G / R) is a period during which panel pixel a represents the G component of the image pixel in the odd row and even column, and a period during which panel pixel b represents the R component of the image pixel in the even row and even column.

[0193] In addition, the unit period (EfC-B) is a period during which panel pixel a represents the B component of the image pixel in odd rows and even columns, and a period during which panel pixel b represents the B component of the image pixel in even rows and even columns.

[0194] In addition, in the third embodiment, the following structure is set, that is, the panel pixel a represents the R component and the panel pixel b represents the G component within the unit period (OfL-R / G) or the unit period (OfC-R / G), the panel pixel a represents the G component and the panel pixel b represents the R component within the unit period (OfL-G / R) or the unit period (OfC-G / R), and the Y component is set through synthesis, and the B component is represented in the remaining period, but it is not limited to this structure.

[0195] For example, in one of the three periods within the field period, one of the panel pixels may be used to represent the G component and the other may be used to represent the B component, in another period, one of the panel pixels may be used to represent the B component and the other may be used to represent the G component, and in the remaining period, the R component may be represented, and the switching may be performed in the order of C (cyan) - CR.

[0196] In addition, for example, in one of the three periods within the field period, one of the panel pixels may be used to represent the R component and the other may be used to represent the B component, in another period, one of the panel pixels may be used to represent the B component and the other may be used to represent the R component, and in the remaining period, the G component may be represented, and switching may be performed in the order of M (magenta) -MG.

[0197] The transmission image based on the liquid crystal panel 100a is an example of the first image light, the light source 151 is an example of the first light source, the R component is an example of the light component of the first color, the G component is an example of the light component of the second color, the B component is an example of the light component of the third color, the P polarized light is an example of the first polarized light, and the polarization optical system 160a is an example of the first polarization conversion member. That is, the device including the light source 151, the polarization optical system 160a, and the liquid crystal panel 100a is an example of the first image light emitting device.

[0198] In addition, the transmission image based on the liquid crystal panel 100b is an example of the second image light, the light source 152 is an example of the second light source, the S polarized light is an example of the second polarized light, and the polarization optical system 160b is an example of the second polarization conversion member. That is, the device including the light source 152, the polarization optical system 160b, and the liquid crystal panel 100b is an example of the second image light emitting device.

[0199] The right side is an example of the first direction, and the bottom side is an example of the second direction. The prism 180 is an example of a synthetic optical system.

[0200] In the above-mentioned first to third embodiments (hereinafter referred to as "embodiments etc."), various modifications or applications are possible as follows.

[0201] In the embodiments and the like, the liquid crystal panels 100 a and 100 b as image light emitting devices are of a transmissive type, but may be of a reflective type.

[0202] In the embodiments, the liquid crystal panels 100a and 100b are configured to display colors sequentially, but for example, one panel pixel may be divided into RGB sub-pixels, and colors may be displayed by the three sub-pixels. In addition, in this configuration, since one panel pixel has RGB sub-pixels, it is not necessary to display colors sequentially, that is, it is possible to display colors without dividing one field period into three unit periods.

[0203] In addition, as the image light emitting device, it is not limited to the liquid crystal panel 100, and a self-luminous display panel may also be used. A self-luminous panel is a display panel that generates an image by emitting light from its own display element, rather than using a light source like the liquid crystal panel 100. As a self-luminous panel, a panel using an OLED (Organic Light Emitting Diode), a micro LED (Light Emitting Diode), or the like as a display element can be applied.

[0204] Fig.17 100c and 100d are diagrams showing a projection type display device to which the structure of the self-luminous panels 100c and 100d is applied as a modified example.

[0205] In this modification, the self-luminous panels 100c and 100d use OLED as display elements. Both the self-luminous panels 100c and 100d have RGB sub-pixels, and the RGB sub-pixels constitute one panel pixel to express colors.

[0206] In this modification, the arrangement of panel pixels in the self-luminous panel 100c and the arrangement of panel pixels in the self-luminous panel 100d are shifted by 0.5 pixels in the horizontal direction (row direction), which is the same as the embodiment.

[0207] Furthermore, since the RGB sub-pixels are provided, colors can be expressed without dividing one field period into three unit periods as described above.

[0208] In addition, the light emitted by the OLED is random light without polarization. Therefore, a polarization optical system 160 a is provided between the self-luminous panel 100 c and the prism 180 , and a polarization optical system 160 b is provided between the self-luminous panel 100 d and the prism 180 .

[0209] In addition, as an image light emitting device, in addition to this, it can also be applied to a reflector element, etc., in which the mirror (reflector) of the reflector element is tilted to a position corresponding to opening or closing, and the incident light is reflected in a specified direction only in either the opening or closing state.

[0210] According to the above-exemplified aspects, for example, the following aspects can be understood.

[0211] A projection display device of mode 1 includes: a first image light emitting device that emits a first image light; a second image light emitting device that emits a second image light; a synthesis optical system that synthesizes the first image light and the second image light in a state where the second image light is shifted relative to the first image light in a first direction and emits the synthesized light; an optical path shifting element that shifts the optical path of the synthesized light emitted from the synthesis optical system; and a display control circuit that controls the first image light emitting device, the second image light emitting device, and the optical path shifting element, wherein one frame period includes a first field period and a second field period, and during the first field period, the display control circuit supplies data signals corresponding to grayscale levels specified by image pixel data arranged in a matrix, data signals of image pixels that are odd numbers in a second direction intersecting the first direction of the image pixel data and arranged along the first direction to the first image light emitting device, and The data signals of the image pixels that are the even-numbered ones in the second direction of the image pixel data and arranged along the first direction are supplied to the second image light emitting device, and the display control circuit controls the optical path shifting element to set the optical path as a reference position. During the second field, the display control circuit supplies the data signals of the image pixels that are the even-numbered ones in the second direction of the image pixel data and arranged along the first direction to the first image light emitting device, and supplies the data signals of the image pixels that are the odd-numbered ones in the second direction of the image pixel data and arranged in the first direction to the second image light emitting device. The display control circuit controls the optical path shifting element to shift the optical path along a second direction intersecting the first direction. The first image light emitting device emits the first image light based on the supplied data signal, and the second image light emitting device emits the second image light based on the supplied data signal.

[0212] According to the projection display device of aspect 1, a high-resolution projection can be realized at low cost.

[0213] In the projection display device of specific mode 2 of mode 1, in the synthetic optical system, the offset amount of the second image light in the first direction relative to the first image light is 0.5 pixels of the pixels in the first image light or the second image light, and the optical path shifting element shifts the optical path by the 0.5 pixels.

[0214] In the projection display device of the specific mode 3 of mode 2, the first image light emitting device comprises: a first liquid crystal panel; a first light source, which emits light to the first liquid crystal panel; and a first polarization conversion component, which converts the light emitted by the first light source into a first polarized light, and the first polarized light is incident on the first liquid crystal panel, and the second image light emitting device comprises: a second liquid crystal panel; a second light source, which emits light to the second liquid crystal panel; and a second polarization conversion component, which converts the light emitted by the second light source into a second polarized light, and the second polarized light is incident on the second liquid crystal panel.

[0215] In a projection display device according to a specific aspect 4 of aspect 3, the first light source and the second light source are laser light sources that respectively emit a first light including a red wavelength band, a second light including a green wavelength band, and a third light including a blue wavelength band.

[0216] In another specific mode 5 of mode 3, the first liquid crystal panel in the first image light emitting device generates images of the light components of the first color, the second color, and the third color by positive polarity writing and negative polarity writing, respectively, and the second liquid crystal panel in the second image light emitting device generates images of the light components of the first color, the second color, and the third color by positive polarity writing and negative polarity writing, respectively.

[0217] In the projection display device of specific mode 6 of mode 5, when the first liquid crystal panel generates image light of the light component of the first color, the second liquid crystal panel generates image light of the light component of the second color, and when the first liquid crystal panel generates image light of the light component of the second color, the second liquid crystal panel generates image light of the light component of the first color.

[0218] In the projection display device of specific mode 7 of any one of modes 3 to 6, during the first field and during the second field, the first image light emitting device generates light components of the first color, the second color, and the third color with different wavelengths in the first image light in a time-division manner, and the second image light emitting device generates light components of the first color, the second color, and the third color in the second image light in a time-division manner.

[0219] In another specific mode 8 of mode 2, the first image light emitting device comprises: a first self-luminous panel, which includes sub-pixels corresponding to a first color, a second color and a third color having different wavelengths, and emits the first image light; and a first polarization conversion component, which converts the emitted light from the first self-luminous panel into a first polarized light, and the second image light emitting device comprises: a second self-luminous panel, which includes sub-pixels corresponding to the first color, the second color and the third color, and emits the second image light; and a second polarization conversion component, which converts the emitted light from the second self-luminous panel into a second polarized light.

Claims

1. A projection display device, characterized in that: The projection display device comprises: A first image light emitting device for emitting a first image light; a second image light emitting device for emitting a second image light; a synthesis optical system for synthesizing the first image light and the second image light in a state where the second image light is shifted in a first direction relative to the first image light, and emitting the synthesized light; an optical path shifting element that shifts the optical path of the synthesized light emitted from the synthesizing optical system; and a display control circuit, which controls the first image light emitting device, the second image light emitting device and the optical path shifting element, One frame period includes the first field period and the second field period. During the first field, the display control circuit supplies, among data signals corresponding to grayscale levels specified by image pixel data arranged in a matrix, data signals of image pixels that are odd-numbered in a second direction intersecting the first direction of the image pixel data and arranged along the first direction to the first image light emitting device, and supplies data signals of image pixels that are even-numbered in the second direction of the image pixel data and arranged along the first direction to the second image light emitting device, The display control circuit controls the optical path shifting element to set the optical path to a reference position. During the second field, the display control circuit supplies data signals of the image pixels that are even-numbered in the second direction of the image pixel data and arranged in the first direction to the first image light emitting device, and supplies data signals of the image pixels that are odd-numbered in the second direction of the image pixel data and arranged in the first direction to the second image light emitting device, The display control circuit controls the optical path shifting element to shift the optical path along a second direction intersecting the first direction. The first image light emitting device emits the first image light based on the supplied data signal, and the second image light emitting device emits the second image light based on the supplied data signal.

2. The projection display device according to claim 1, characterized in that: In the synthetic optical system, the amount of displacement of the second image light relative to the first image light in the first direction is 0.5 pixels of pixels in the first image light or the second image light, The optical path shifting element shifts the optical path by the 0.5 pixel.

3. The projection display device according to claim 2, characterized in that: The first image light emitting device comprises: 1st liquid crystal panel; a first light source that emits light toward the first liquid crystal panel; and a first polarization conversion component that converts the light emitted by the first light source into a first polarized light, The first polarized light is incident on the first liquid crystal panel. The second image light emitting device comprises: The second liquid crystal panel; a second light source that emits light toward the second liquid crystal panel; and a second polarization conversion component that converts the light emitted by the second light source into a second polarized light, The second polarized light is incident on the second liquid crystal panel.

4. The projection display device according to claim 3, characterized in that: The first light source and the second light source are laser light sources that respectively emit a first light including a red wavelength band, a second light including a green wavelength band, and a third light including a blue wavelength band.

5. The projection display device according to claim 3, characterized in that: The first liquid crystal panel in the first image light emitting device generates images of light components of the first color, the second color, and the third color by positive polarity writing and negative polarity writing, respectively. The second liquid crystal panel in the second image light emitting device generates images of the light components of the first color, the second color, and the third color by positive polarity writing and negative polarity writing, respectively.

6. The projection display device according to claim 5, characterized in that: When the first liquid crystal panel generates image light of the first color light component, the second liquid crystal panel generates image light of the second color light component. When the first liquid crystal panel generates image light of the second color light component, the second liquid crystal panel generates image light of the first color light component.

7. The projection display device according to any one of claims 3 to 6, characterized in that: During the first session and during the second session, The first image light emitting device generates a first color light component, a second color light component, and a third color light component having different wavelengths in the first image light in a time-division manner. The second image light emitting device generates the light component of the first color, the light component of the second color, and the light component of the third color in the second image light in a time-division manner.

8. The projection display device according to claim 2, characterized in that: The first image light emitting device comprises: a first self-luminous panel, comprising sub-pixels corresponding to a first color, a second color, and a third color having different wavelengths, and emitting the first image light; and a first polarization conversion component that converts the outgoing light from the first self-luminous panel into a first polarized light, The second image light emitting device comprises: a second self-luminous panel, comprising sub-pixels corresponding to the first color, the second color, and the third color, and emitting the second image light; and The second polarization conversion component converts the outgoing light from the second self-luminous panel into a second polarized light.

Images