JP2021026195A - Projection type display device - Google Patents

Abstract

To provide a display device capable of modulating luminance for each of RGB on a modulator for modulating luminance.SOLUTION: The projection-type display device includes: irradiation means that emits light; first optical modulation means that performs RGB optical modulation in a time division; and second optical modulation means that separates a luminous flux from the first modulation means into RGB to play each RGB on a panel by receiving each RGB luminous flux. An image is generated by the first optical modulation means and the second optical modulation means.SELECTED DRAWING: Figure 1

Description

The present invention relates to a projection type display that projects onto a screen with a projection lens, and relates to a video device that improves contrast.

The liquid crystal display device has a structure in which each pixel of the liquid crystal panel acts as a shutter of light while shining light from a light source. As a problem of such a display device, there is a problem that the contrast is lowered due to diffused light of a liquid crystal panel, optical leakage light, or the like.

Therefore, in recent years, projectors and liquid crystal displays have been proposed in which the contrast is dramatically improved by performing double modulation.

The double modulation in the projector of Patent Document 1 has a configuration in which a first modulation unit that performs color modulation and a second modulation unit that performs luminance modulation are optically connected in series. In the double modulation method in the present document, the contrast is increased by displaying the image of the first modulation optical system in black and the second modulation optical system in black with respect to the black signal as the input. Can be raised. For example, when the contrast of the first modulation optical system is 1000: 1 and the contrast of the second modulation optical system is 1000: 1, the contrast obtained by multiplying is finally obtained, so that the contrast of 1000000: 1 can be obtained.

Japanese Unexamined Patent Publication No. 2005-241738

However, in the prior art disclosed in Patent Document 1 above, the luminance modulation can be performed only in the state where RGB is synthesized with respect to the second modulation unit that performs the luminance modulation, and the luminance modulation is performed for each RGB. I couldn't do it.

An object of the present invention is to provide a display device that performs luminance modulation for each RGB with respect to a modulation unit that performs luminance modulation.

In order to achieve the above object, the projection device according to the present invention is
Irradiation means to irradiate light and
A first optical modulation means that performs RGB optical modulation in a time division manner,
A second optical modulation means that separates the light flux from the first modulation means into RGB and receives each of the RGB light fluxes to display an RGB panel, respectively.
The image is generated by the first optical modulation means and the second optical modulation means.

According to the projection apparatus according to the present invention, by performing double modulation using an RGB color modulation panel and a luminance modulation panel that can modulate each RGB, the luminance is modulated for each RGB to improve the contrast and at low brightness. Color purity can be increased. At that time, by controlling the driving method of each panel, it is possible to improve the color purity and the contrast while suppressing the deviation of the modulation of the display state.

Block diagram showing the features of the first and second embodiments Detailed view of DA conversion unit Timing chart of DA conversion unit LCD panel block diagram LCD panel timing chart Liquid crystal panel circuit diagram Detailed configuration of the luminance modulation panel Luminance modulation panel drive timing chart Optical system block diagram of the first embodiment Detailed block diagram of image output unit 601 Timing chart of the luminance modulation panel and the pixel liquid crystal panel of the first embodiment Pixel transition of luminance modulation of the first embodiment Projected image display Timing chart of the luminance modulation panel and the pixel liquid crystal panel of the second embodiment Pixel transition of luminance modulation of the second embodiment Optical system block diagram of the third embodiment

Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing the features of the image display device of the present invention.

The display device 1000 is shown in FIG. The control unit 501 performs various calculations / controls and communicates with other display devices, and also has a storage unit. The storage unit 510 is connected to the control unit 501, stores setting values and the like for each circuit block, and sets or the like in each circuit block via the control unit 501.

The focus detection unit 201 detects the distance from the display device to the screen on which the projection is performed by the focus detection sensor, and the focus detection signal is input to the control unit 501.

The control unit 501 outputs a lens control signal from the focus detection unit 201 to the lens drive unit 541 based on the focus detection signal, and displays the AF lens 542 included in the projection optical unit 529 on a screen or the like as an image of the pixel liquid crystal panel 100 described later. Drive so that the projection part of the lens is in focus.

Further, the lens driving unit 541 drives the AF lens 542 and also drives the zoom lens 543 included in the projection optical unit 529 to change the projection magnification of the image of the pixel liquid crystal panel 100 described later on a screen or the like.

The image detection unit 202 uses an image sensor such as a CCD or CMOS to input an image signal to the control unit 501 via the image input processing unit 203. The flicker detection unit 204 detects the flicker of the projected image and inputs it to the control unit 501.

The lens shift unit 544 shifts the projection lens of the projection optical unit 529 including the AF lens 542 and the zoom lens 543 vertically and horizontally, and shifts the projection position of the image of the pixel liquid crystal panel 100 described later on the screen or the like vertically and horizontally. The pixel liquid crystal panel 100, which is a display means, forms an image on the pixel liquid crystal panel 100 based on the data from the image output unit 601. Further, the brightness modulation panel block 700, which is a light amount control means, receives the light flux from the light source unit 527 based on the data from the image output unit 601 and receives the light flux from the light source unit 527 based on the data from the image output unit 601 and the pixels of the pixel liquid crystal panel 100, like the pixel liquid crystal panel 100 described above. Control the brightness of.

The communication unit 552 communicates between the display device 1000 and another display device.

As a flow of the video system, for example, in the case of a video display device such as a projector, an image is input from an external video source source (not shown) via an input terminal 551. The signal input from the video input terminal is an analog signal such as a component, or a digital signal output from DVI, HDMI (registered trademark), a wireless input unit (not shown), or the like. The control unit 501 transmits a control signal to the image input unit 522 based on the setting information from the input unit 530 including the power supply SW / mode SW, zoom SW, image input switching SW, etc. installed in the image display device. To do. This image input The image input unit 522 selects analog signal input or digital signal input input from the input terminal 551 according to the control signal from the control unit 501, and performs A / D conversion processing or decoding processing on the image signal. And so on. Then, the image processing unit 523 performs known noise removal, contour enhancement, image scaling, keystone correction, and the like, and outputs the image data to the image output unit 601.

For the output image data that has been subjected to various image processing by the image processing unit 523, processing such as a synchronization signal of the double speed drive timing of the output image data and gamma conversion is performed by the image output unit 601 and a memory such as SDRAM. Further, an image data signal for driving the pixel liquid crystal panel 100 is output. The drive data is also output to the luminance modulation panel block 700. The image output unit 601 is a block that exhibits the features of the present invention, and details will be described later. The image data signal for driving the pixel liquid crystal panel 100 is converted into an analog signal by the pixel DA conversion unit 531.

The pixel liquid crystal panel 100 is composed of three panels for R, G, and B. Each of the RGB liquid crystals receives a synchronization signal of double speed drive timing and a liquid crystal drive signal converted into an analog signal by the pixel DA conversion unit 531 in the previous period, that is, a so-called Video signal, and an image is formed on the pixel liquid crystal panel 100.

In this formed image, the light transmitted through the luminance modulation panel block 700 and the relay optical system 528 is color-separated into red (R), green (G), and blue (B), and red (R) and green (R) and green ( An image on each pixel liquid crystal panel 100 for G) and blue (B) is generated. The image generated by the luminance modulation panel block 700 and the pixel liquid crystal panel 100 is projected via the projection optical unit 529 and projected on the screen.

The reference voltage DA conversion unit 520 has a plurality of output channels, receives a communication signal from the control unit 501, and has a Vcom voltage which is an electrode voltage facing the pixel electrode of the pixel liquid crystal panel 100, and a pixel DA conversion unit 531. Drive voltage Generates the set voltage.

The driving operation of the pixel liquid crystal panel 100 will be described with reference to FIGS. 2, 3 and 4.

FIG. 2 is a schematic view of the pixel DA conversion unit 531, and receives input signals of CLK, DAT, Latch, and INV from the image output unit 601 of FIG. 1 to generate liquid crystal drive signals Video0 to Video7. The timings of the input data, CLK, DATA, Latch, and output signals Video0 to Video7 are as shown in FIG. 3, and the DATA for the Video output is transferred to a register (not shown) in the DA conversion unit 531 by the rising signal of CLK. Further, the INV signal outputs a video output which is an analog voltage by inverting the voltage to +-with respect to a predetermined center voltage according to the data input from the DAT. Here, assuming that the video output is 8 channels, the DATA is transferred at the rising edge of the Latch signal after the DATA is transferred for 8 clocks. The video signal updates the video signal to the Data signal of DATA before the ratch signal rises at the rise of CLK after the fall of the Latch signal. By repeating this process, a liquid crystal drive signal to the pixel liquid crystal panel 100 is generated.

As shown in FIG. 4, the pixel liquid crystal panel 100 is composed of an H shift register 110, a V shift register 120, and a pixel unit 130. The H scanning operation shown in FIG. 5 is the H shift register 110, and the HS signal is used as the reset signal and the start signal of the H shift register. The liquid crystal drive signals of Video 0 to Video 7 are vertically scanned by turning on the signal lines of 8 lines while updating the liquid crystal drive signals of Video 0 to Video 7 for each clock of the HCLK signal. That is, HCLK and the Latch signal shown in FIG. 3 have the same frequency. For example, here, when the resolution of the pixel liquid crystal panel 100 is set to H: 1024 × V: 768 of XGA, the display portion of the pixel liquid crystal panel 100 is scanned in the H direction with an HCLK: 128 clock. Then, the next HS signal is used to perform H scanning of the next V line as a reset signal and a start signal of the H shift register 110. Actually, H scanning is performed with several clocks, that is, so-called blanking added to the HCLK: 128 clocks required for scanning in the H direction.

In the V scan, the VS signal is used as the reset signal and the start signal of the V shift register 120, and the V shift register 120 shifts the H line for each clock of the VCLK signal to obtain a resolution of XGA H: 1024 × V :. When 768 is set, the display portion of the pixel liquid crystal panel 100 in the V direction is scanned with VCLK: 768 clock. Actually, as in the case of H scanning, V scanning is performed with a number of clocks plus blanking for VCLK: 768 clocks required for scanning in the V direction. The number of blankings is arbitrary.

A liquid crystal drive signal is applied to the pixel portion 130 in the pixel liquid crystal panel 100 by each scanning signal of the H scanning signal / V scanning signal.

Further, eight black regions (Vcom voltage is applied to the pixels) are provided on the top, bottom, left and right of the display pixels H: 1024 × V: 768, and the liquid crystal drive signal is applied by the blanking clock. However, when the pixel position shift occurs, the position of writing the video signal to the pixel portion 130 in the pixel liquid crystal panel 100 is shifted by using eight pixels in the black areas of the top, bottom, left, and right to perform the alignment.

The pixel unit 130 is configured as shown in FIG. 6, the H shift register 110 operates by HCLK as described above, and the transfer SW145 is turned on by the H shift register output 148 to transfer the Voltage signal 149 from the pixel DA conversion unit 531 to the signal line 147. A Pixel signal voltage is applied to. Then, the shift register output 146 of the V shift register 120 drives the gate of the NMOS 141 to accumulate the Video signal voltage in the pixel capacitance 142. The liquid crystal LC143 changes the transmittance of light deflected by the negatively illustrated polarizing plate according to the pixel capacity 142.

An example of the constituent blocks of the luminance modulation panel block 700 is shown in FIG. The luminance modulation panel block 700 is composed of a luminance modulation panel 702, a time division multiplexing circuit 701, and a color wheel 710. Further, it is assumed that the color wheel 710 is composed of G, R, and B color filters having a central angle of 120 degrees, respectively, and is set to make one rotation at 120 Hz. The brightness modulation panel 702 receives a drive signal from the image output unit and PWM-drives one frame of RGB gradation into time divisions (RGB3 division), and reflects the light received from the light source unit 527 (PWM drive time). ) Adjusts the brightness. Further, it is configured between the light source unit 527 and the luminance modulation panel 702 via a condensing system 740 and a color wheel 710 having at least an RGB surface to display RGB colors. The luminance modulation panel 702 has XGA pixels like the pixel liquid crystal panel 100.

In FIG. 7, the RGB color signal, which is an 8-bit digital signal, is input to the time division multiplexing circuit 701, which is the drive circuit of the brightness modulation panel 702. Each RGB color signal input to the time division multiplexing circuit 701 at 120 Hz is time-compressed in a period of 1/3 of each of RGB and output as a one-field period. FIG. 8 shows how the one-field period is time-division-multiplexed. The luminance modulation panel 702 is controlled by this output signal. Further, the light collected by the condensing system 740 from the light source unit 527 passes through the color wheel 710 and then reaches the luminance modulation panel 702. In this case, the light transmitted through the color wheel 710 is separated into RGB at each predetermined interval and reaches the luminance modulation panel 702.

In FIG. 8, each color of RGB is numbered in order from the front side of the divided fields. Here, it is assumed that the color wheel 710 is clockwise and the light from the light source unit 527 hits the position of 0 degrees. The RGB light of each color is reflected by the luminance modulation panel 702 controlled by the RGB signal for a corresponding period, and the output RGB light is perceived as a color image.

At this time, each field of the RGB signal is further composed of a plurality of time-divided subfields so that the gradation can be expressed. As an example of the subfield period, the subfield configuration of the first field of R in the case of expressing the gradation of 8 bits, that is, 256 gradations is shown at the lower side of FIG. The time length of each subfield is weighted corresponding to the brightness of one color when only the subfield is turned on, and this weight is applied to the luminance modulation panel 702 in the case of the configuration of FIG. Corresponds to the time when is on (lit). The data is transferred to the luminance modulation panel 702 in the field before the display field.

Next, the details of the projection system from the light source unit 527 to the condensing system 740, the luminance modulation panel block 700, the relay optical system 528, the pixel liquid crystal panel 100, and the projection optical unit 529 will be described with reference to FIG.

The light flux projected from the light source unit 527 is collected by the light collecting system 740 and irradiated to the luminance modulation panel 702 via the color wheel 710 and the prism 730 in the luminance modulation panel block 700. The color wheel 710 separates the luminous flux into red, green, and blue by time division. The time-divided red, green, and blue lights are applied to the luminance modulation panel 702, and the luminance modulation panel 702 is switched on / off by PWM of 256 gradations, so-called panel drive. The light flux passing through the luminance modulation panel 702 is reflected by the prism 730 and is incident on the relay optical system 528.

Then, the luminous flux incident on the relay optical system 528 transmits the incident light through the dichroic mirror 808 through green (G) and redistributes red (R) and blue (B) as reflections again.

The polarizing beam splitter 813a, the polarizing beam splitter 813b, and the polarizing beam splitter 813c relay the light beam of the brightness modulation panel 702 to the pixel liquid crystal panel 100 of each RGB by the polarizing separation film 814a, the polarization separation film 814b, and the polarization separation film 814c, respectively. The light imaged by the above is incident. Also, each polarizing beam splitter transmits the reflected light of the panel.

Then, for red, light is incident on the projection optical unit 529 via the red 1/4 retardation plate 810r and the red birefringence filter 811r. For green, light is incident on the projection optical unit 529 via a green 1/4 retardation plate 810 g and a green birefringence filter 811 g. For blue, light is incident on the projection optical unit 529 via the blue 1/4 retardation plate 810b and the blue birefringence filter 811b.

The display image of the luminance modulation panel 702 is configured to form an image on the pixel liquid crystal panel 100 by the relay optical system 528. Therefore, the luminance modulation panel 702 modulates the luminance of a predetermined pixel or a pixel in a partial region of the pixel liquid crystal panel 100 of each color. Then, an image is generated by synthesizing the reflectances of the pixel liquid crystal panel 100 and the luminance modulation panel 702.

Then, the luminous flux image-formed by the pixel liquid crystal panel 100 and the luminance modulation panel 702 synthesizes RGB images via the polarizing beam splitter 813a, the polarizing beam splitter 813b, and the polarizing beam splitter 813c.

Then, the combined light flux is projected onto the screen via the projection optical unit 529.

The image output unit 601 will be described with reference to FIG.

The image output unit 601 is composed of a double speed unit 602, a double speed memory 603, and a luminance modulation data generation unit 604. Double-speed drive output data is generated by writing each 60 Hz image processing data sent by the image processing unit 523 to the double-speed unit 602 and the double-speed memory 603 and reading the data twice within a time of 60 Hz. The luminance modulation data generation unit 604 generates the luminance modulation image data in the luminance modulation data generation unit 604 based on the output data of the double speed drive created by the luminance section 602.

Further, the luminance modulation data generation unit 604 is composed of a luminance modulation unit 610, a time division memory 620, and a timing generator 630. From the output data of the double speed drive sent by the double speed unit 602, the brightness modulation unit 610 generates the brightness modulation image data. The luminance modulation unit 610 generates luminance-modulated image data to be output to the luminance modulation panel 702 and the pixel liquid crystal panel 100, respectively. Each luminance-modulated image data generated by the luminance modulation unit 610 is transmitted to the timing generator 630. The timing of the data to be transmitted is shifted by a certain time so that the target luminance-modulated image is generated by the TG1 in the timing generator 630 and the time-division memory 620. Further, data for driving the pixel liquid crystal panel 100 is transmitted to the luminance modulation panel 702 by the TG2 in the timing generator 630, and the pixel liquid crystal panel 100 described above is driven.

The timing frame for transmitting the brightness-modulated image data of each of the RGB to the pixel liquid crystal panel 100 depends on the frame period for expressing RGB of the brightness-modulated panel 702.

The features of the present embodiment of the timing frame will be described with reference to FIG.

The input data N sent by the image processing unit 523 is doubled by displaying two frames for one frame of N1, N2 and input from the double speed unit 602 and the double speed memory 603 of the image output unit 601. Further, the doubled speed data is further transferred by TG1 in the timing generator 630 to the pixel liquid crystal panel_G and the pixel liquid crystal panel with respect to the pixel liquid crystal panel_R such as Nr1, Nr2, Ng1, Ng2, Nb1 and Nb2. _B delays the display.

In the pixel liquid crystal panel 100, the image data of N1 is sequentially written to each pixel in the period of one frame as described above, and the image data of N1 of each pixel is held until the next image data of N2 is written, and according to the data. The above-mentioned PWM drive is performed.

The luminance modulation panel 702 is time-divisioned for each frame RGB, is driven with each color as one field, is written in batches according to the data, and holds image data for one field.

The timing of writing to the pixel liquid crystal panel 100 of each RGB depends on the rotation of the color wheel 710. The color wheel 710 makes one rotation in one frame (each RGB is displayed once), and the luminance modulation panel 702 enables RGB luminance modulation in one frame.

The timing of writing Ng1 is delayed for the R frame of the color wheel 710 with respect to the writing of Nr1 (see section (1)). Further, the timing of writing Nb1 is delayed by the amount of the G frame of the color wheel 710 with respect to the writing of Ng1 (see section (2)). Further, the timing of writing Nr2 is delayed by the frame of B of the color wheel 710 with respect to the writing of Nb1 (see section (3)). It is assumed that writing is continuously performed on the RGB pixel liquid crystal panel 100 at the above timing.

Here, regarding the RGB timing of the color wheel 710 of FIG. 11, the R field is (1), the G field is (2), and the B field is (3). At the timing (1), the writing of R of the pixel liquid crystal panel 100 is started. In the luminance modulation panel 702, the luminance modulation panel 702 is time-controlled based on the generated luminance modulation data, and is driven to perform the luminance modulation of R. Further, at the timing (2), the writing of G of the pixel liquid crystal panel 100 is started. The writing state of G of the pixel liquid crystal panel 100 at the timing (2) is the same as the writing state of R of the pixel liquid crystal panel 100 at the timing (1). In the luminance modulation panel 702, the luminance modulation panel 702 is time-controlled based on the generated luminance modulation data, and is driven to perform the luminance modulation of G. At the timing (3), the writing of B of the pixel liquid crystal panel 100 is started. The writing state of G of the pixel liquid crystal panel 100 at the timing (3) is the same as the writing state of R of the pixel liquid crystal panel 100 at the timing (1). In the luminance modulation panel 702, the luminance modulation panel 702 is time-controlled based on the generated luminance modulation data, and the luminance modulation of B is driven.

Therefore, the image data of R is projected at the timing (1), the image data of G is projected at the timing (2), and the image data of B is projected at the timing (3), and one picture is projected in one frame.

That is, the display states of RGB of the pixel liquid crystal panel 100 are the same.

The input data N1 will be described with reference to FIG.

The input data N1 is RGB-divided data, and becomes Nr1, Ng1, and Nb1. The RGB input data Nr1, Ng1, and Nb1 are output at the above timings, respectively. The output of Nr1 of the pixel liquid crystal panel 100_R is luminance-modulated to Nr1'by the luminance modulation panel 702 during the period of R of the color wheel 710. Further, regarding the output of Ng1 of the pixel liquid crystal panel 100_G, the color wheel 710 is luminance-modulated to Ng1'in the period of G by the luminance modulation panel 702. Further, regarding the output of Nb1 of the pixel liquid crystal panel 100_B, the color wheel 710 is luminance-modulated to Nb1'in the period of B by the luminance modulation panel 702. Therefore, by sequentially outputting the image data of Nr1', Ng1', and Nb1'in one frame, it is output as the luminance-modulated image data of N1'.

For example, in the case of white and black as shown in FIG. 13 (1), the display state of the white portion and the black portion is expressed by the gradation of the pixel liquid crystal panel 100 and the luminance modulation panel 702. It is assumed that each of RGB is represented by 8-bit 256 gradations. In the white display portion, for example, if the gradation of each RGB of the pixel liquid crystal panel 100 is R255, G255, and B255, the gradation of each RGB of the luminance modulation panel 702 can be expressed by R255, G255, and B255. Further, in the black display portion, for example, if the gradation of each RGB of the pixel liquid crystal panel 100 is R0, G0, B0, the gradation of each RGB of the luminance modulation panel 702 can be expressed by R0, G0, B0. Since the black display portion has leakage light of the optical system, black appears to float even if the gradation of the pixel liquid crystal panel 100 is 0. Here, by setting the gradation of the luminance modulation panel 702 to 0, black can be further submerged and black can be expressed.

Further, in the case of red and black as shown in FIG. 13 (2), the display state of the red portion and the black portion is expressed by the gradation of the pixel liquid crystal panel 100 and the luminance modulation panel 702. It is assumed that each of RGB is represented by 8-bit 256 gradations. In the red display portion, for example, if the gradation of each RGB of the pixel liquid crystal panel 100 is R200, G10, B10, the gradation of each RGB of the luminance modulation panel 702 can be expressed by R200, G10, B10. Further, in the black display portion, for example, if the gradation of each RGB of the pixel liquid crystal panel 100 is R0, G0, B0, the gradation of each RGB of the luminance modulation panel 702 can be expressed by R0, G0, B0. By modulating each RGB gradation of the brightness modulation panel 702 with respect to each RGB gradation of the pixel liquid crystal panel 100, it is possible to perform luminance modulation for each RGB.

The number of pixels of the pixel liquid crystal panel 100 and the luminance modulation panel 702 may be the same or different, and the number of pixels of the luminance modulation panel 702 may be small. If the luminance modulation panel 702 is the same, the luminance modulation may be performed for each pixel. When the luminance modulation panel 702 is smaller than the pixel liquid crystal panel 100, the luminance modulation in the area may be performed by using a relay optical system 528 that blurs the focus of the luminance modulation panel 702.

Further, in the present embodiment, the pixel liquid crystal panel and the luminance modulation panel are not limited to analog drive type liquid crystal panels, digital drive liquid crystal panels, transmissive type, reflective type, and DLP panels. Needless to say.

The pixel liquid crystal panel in the present description may be a sequential write drive type panel, and the luminance modulation panel may be a time division drive type panel.

The block diagram showing the features of the image display device in this embodiment is FIG. 1 as in the first embodiment. Further, in the optical configuration, FIG. 9 is the same as in the first embodiment.

Next, the features of this embodiment will be described with reference to FIG.

The generated data transmitted to the pixel liquid crystal panel 100 by the luminance modulation unit 610 generates blanking of about 1/3 frame in each RGB frame. Writing is performed on the pixel liquid crystal panel 100 at a time of 2/3 of 1/120 Hz. At that time, the display image is completed.

It is assumed that the color wheel 710 repeats RGB in one frame. Here, regarding the RGB timing of the color wheel 710, the R field is (1), the G field is (2), and the B field is (3). The image data of R is transmitted so that the blanking of the red output of the pixel liquid crystal panel 100 is started at the timing (1) when the red color wheel 710 is started. Further, at the timing (2) when the green of the color wheel 710 is started, the image data of G is transmitted by the TG1 in the timing generator 630 so that the blanking of the green output of the pixel liquid crystal panel 100 is started. Further, at the timing (3) when the blue of the color wheel 710 is started, the image data of B is transmitted by the TG1 in the timing generator 630 so that the blanking of the blue output of the pixel liquid crystal panel 100 is started. Hereinafter, the above operation is repeated for the pixel liquid crystal panel 100.

At the timing (1), the writing of R of the pixel liquid crystal panel 100 is completed and the state is blank. In the luminance modulation panel 702, the luminance modulation panel 702 is time-controlled based on the generated luminance modulation data, and is driven to perform the luminance modulation of R. Further, at the timing (2), the writing of G of the pixel liquid crystal panel 100 is completed and the state is blank. In the luminance modulation panel 702, the luminance modulation panel 702 is time-controlled based on the generated luminance modulation data, and is driven to perform the luminance modulation of G. At the timing (3), the writing of B of the pixel liquid crystal panel 100 is completed and the state is blank. In the luminance modulation panel 702, the luminance modulation panel 702 is time-controlled based on the generated luminance modulation data, and the luminance modulation of B is driven.

Therefore, the image data of R is projected at the timing (1), the image data of G is projected at the timing (2), and the image data of B is projected at the timing (3), and one picture is projected in one frame.

The input data N1 will be described with reference to FIG. The input data N1 is time-divisioned for each of RGB to become Nr1, Ng1, and Nb1. The RGB input data Nr1, Ng1, and Nb1 are output at the above timings, respectively. The output of Nr1 of the pixel liquid crystal panel 100_R is luminance-modulated to Nr1'by the luminance modulation panel 702 during the period of R of the color wheel 710. Further, regarding the output of Ng1 of the pixel liquid crystal panel 100_G, the color wheel 710 is luminance-modulated to Ng1'in the period of G by the luminance modulation panel 702. Further, regarding the output of Nb1 of the pixel liquid crystal panel 100_B, the color wheel 710 is luminance-modulated to Nb1'in the period of B by the luminance modulation panel 702. Therefore, by sequentially outputting the image data of Nr1', Ng1', and Nb1'in one frame, it is output as the luminance-modulated image data of N1'.

By performing luminance modulation of each color by the luminance modulation panel 702 during the blanking of the pixel liquid crystal panel 100 of each RGB, it is possible to suppress the deviation of the image display state of each of RGB.

The above-mentioned blanking period is not limited to a specific time, but is a light source time division period as RGB, that is, 1/3 or less of one frame, and the drive control of the luminance modulation panel 702 is performed during that period.

In this embodiment, the optical configuration is different from that of the first embodiment. However, the method of driving each panel is the same as that of the first and second embodiments.

The details of the projection system from the light source unit 527 to the condensing system 740, the pixel liquid crystal panel 100, the relay optical system 528, the brightness modulation panel block 700, and the projection optical unit 529 will be described with reference to FIG.

The luminous flux projected from the light source 527 and incident by the condensing system 740 disperses the incident light through the dichroic mirror 808 by transmitting the incident light through green (G) and reflecting red (R) and blue (B).

The polarizing beam splitter 813a, the polarizing beam splitter 813b, and the polarizing beam splitter 813c make light incident on the pixel liquid crystal panel 100 of each RGB by the polarizing separation film 814a, the polarization separation film 814b, and the polarization separation film 814c, respectively, and the reflected light of the panel is emitted. Make it transparent.

The red color causes light to enter the relay optical system 528 via the red 1/4 retardation plate 810r and the red birefringence filter 811r. For green, light is incident on the relay optical system 528 via a green 1/4 retardation plate 810 g and a green birefringence filter 811 g. For blue, light is incident on the relay optical system 528 via the blue 1/4 retardation plate 810b and the blue birefringence filter 811b.

The combined luminous flux is applied to the luminance modulation panel 702 via the relay optical system 528, the color wheel 710, and the prism 730 in the luminance modulation panel block 700. The color wheel 710 separates the luminous flux into red, green, and blue by time division. The time-division red, green, and blue lights are applied to the luminance modulation panel 702, and the luminance modulation panel 702 is switched ON / OFF. The light flux passing through the luminance modulation panel 702 is reflected by the prism 730, and an image is formed by the projection optical unit 529 and projected onto the screen.

The display image of the luminance modulation panel 702 is configured such that the image of the pixel liquid crystal panel 100 is formed by the relay optical system 528. Therefore, the luminance modulation panel 702 modulates the luminance of a predetermined pixel or a pixel in a partial region of the pixel liquid crystal panel 100 of each color. Then, an image is generated by synthesizing the reflectances of the pixel liquid crystal panel 100 and the luminance modulation panel 702.

The driving method and driving timing of the pixel liquid crystal panel 100 and the luminance modulation panel 702 are the same as those in the first embodiment.

100-pixel liquid crystal panel, 130-pixel section, 141 NMOS,
142 pixel capacity, 43 LC, 45 transfer SW,
146 shift register output, 147 signal lines,
148 H shift register output, 149 Video signal,
201 Focus detection unit, 202 image detection unit, 203 image input processing unit,
204 Flicker detector, 501 control unit, 510 storage unit,
520 reference voltage DA conversion unit, 522 image input unit,
523 image processing unit, 527 light source unit, 528 relay optical system,
529 projection optical unit, 530 input unit, 531 pixel DA conversion unit,
541 lens drive unit, 542 AF lens, 543 zoom lens,
544 lens shift unit, 551 input terminal, 552 communication unit,
601 image output section, 602 double speed section, 603 double speed memory,
604 Luminance Modulation Data Generator, 610 Luminance Modulation Unit,
620 time division memory, 630 timing generator,
702 Luminance Modulation Panel, 701 Time Division Multiplexing Circuit,
710 color wheel, 730 prism, 740 condensing system,
808 dichroic mirror, 810b blue 1/4 retardation plate,
810g green 1/4 retardation board, 810r red 1/4 retardation board,
811b blue birefringence filter, 811g green birefringence filter,
811r red birefringence filter, 813a polarizing beam splitter,
813b Polarized beam splitter,
813c Polarizing Beam Splitter, 814a Polarized Separation Membrane,
814b Polarized Separation Membrane, 814c Polarized Separation Membrane, 1000 Display,
110 H shift register, 120 V shift register,
700 Luminance Modulation Panel Block

Claims (7)

Irradiation means to irradiate light and
A first optical modulation means that performs RGB optical modulation in a time division manner,
A second optical modulation means that separates the light flux from the first modulation means into RGB and receives each of the RGB light fluxes to display an RGB panel, respectively.
Have,
A projection device characterized in that an image is generated by the first light modulation means and the second light modulation means. The projection apparatus according to claim 1, wherein the light flux from the light source is modulated by the second light modulation means after the modulation by the first light modulation means. The projection apparatus according to claim 1, wherein the light flux from the light source is modulated by the first light modulation means after the modulation by the second light modulation means. Claim 1 or claim, wherein the first optical modulation means is driven by shifting the display timing of each RGB of the second optical modulation means with respect to each color in one frame represented by time division. Item 2. The projection device according to item 2. Claim 1 or claim, wherein the drive data generation means of the second optical modulation unit is usually written in one frame (1/120 Hz), but generates blanking in one frame. 2. The projection device according to 2. The projection device according to claim 1 or 2, wherein the first optical modulation unit enables modulation of at least RGB in one frame. The projection device according to claim 1 or 2, wherein the first optical modulation unit can modulate at least RGB with one panel.