JP2002077932A - Video display device and method for driving liquid crystal panel therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To display a bright color picture by improving light utilization efficiency in a video display device using a single liquid crystal panel. SOLUTION: A light W emitted from a lamp 11 is resolved into three primary color lights R, G, and B through a dichroic mirrors 14r and 14b, and they are made to be incident on a light path switching part 21 from three directions 120 degrees apart from each other. The light path switching part 21 is provided with three light guide paths 25a to 25c. The three primary color lights emitted from the respective outgoing outlets are led through illumination light guide paths 22a to 22c to a crystal panel 20, and they are directed respectively onto three areas that the crystal panel 20 is divided into three in the vertical scanning direction. In this case, a motor 32 is turned by a motor rotation control unit 33 while the optical path switching part 21 is synchronized with a video signal Sv, so that the three primary color lights are directed on different positions on the crystal panel 20 at the same time, and the position of emitting the respective color lights is moved while synchronizing with the video display position on the liquid crystal panel 20.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a video display device for displaying a color image using a single liquid crystal panel.

[0002]

2. Description of the Related Art In recent years, with the development of video equipment such as video tape recorders and video disk players and video software, there has been an increasing demand for large-screen video display devices for enjoying powerful videos. As a conventional large-screen image display device, there is an image display device that uses a liquid crystal panel for an image display unit, spatially modulates light emitted from a light source with the liquid crystal panel, and projects an image on a screen or the like.

In a video display apparatus employing a liquid crystal panel in a video display section, conventionally, three or one liquid crystal panel is used to obtain a color image, and a user can directly view or project a video displayed on the liquid crystal panel. Enlarged projection display is performed using a lens. An example of a video display device using one liquid crystal panel for a video display unit is disclosed in, for example,
There is one disclosed in Japanese Patent No. 318939.

FIG. 9 is a block diagram showing a configuration of a video display device disclosed in Japanese Patent Application Laid-Open No. 07-318939. This image display device includes a liquid crystal panel 111, a color filter 113, a light source 115, a liquid crystal driving unit 116, a motor 117, and a rotation control unit 118. The liquid crystal panel 111 sequentially displays achromatic color gradation images for red, green, and blue. On the front side or the back side of the liquid crystal panel 111, a color filter 113 provided with three primary color fields of red, green and blue in a predetermined order is arranged. The rotation control unit 118 and the motor 117 rotate the color filter 113 in synchronization with the image display timing of the liquid crystal panel 111. Thus, the light from the light source 115 is sequentially modulated by the color filter 113 and the liquid crystal panel 111 with red, green, and blue video signals and enters the human eye, where it is recognized as a color image. Note that the black mask portion 114 on the color filter 113 is
This is to prevent a field of another color from being positioned on an image for a predetermined color on the liquid crystal panel 111, and to prevent display colors from becoming cloudy due to mixed colors.

[0005]

In the above-described conventional image display device, the color filters are rotated in synchronization with the red, green, and blue images displayed in a predetermined order on the liquid crystal panel. Displayed a color image. In the conventional image display device configured as described above, since images of three primary colors are displayed in a time-divided manner, while displaying an image of a specific one color, light of the other two colors is displayed. Is not used. For this reason, the use efficiency of the light from the light source is reduced to 1/3, and the brightness of the displayed image is not sufficient. In a video display device using three liquid crystal panels corresponding to the three primary colors, light use efficiency can be improved, but the video device becomes large and costs increase.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a video display device which realizes a color image display by temporally dividing and displaying images of three primary colors using a single liquid crystal panel. An object of the present invention is to provide a video display device capable of displaying a sufficiently bright color image by improving the use efficiency.

[0007]

Means for Solving the Problems and Effects of the Invention A first aspect of the present invention is to provide a liquid crystal panel driven based on a color video signal by irradiating the single liquid crystal panel with light, thereby obtaining the transmitted video or reflected light. A video display device that displays a color image represented by a signal, a light source that emits white light,
A color separation optical system that separates the white light into light of three colors, red, green, and blue; and first, second, and third regions obtained by dividing the liquid crystal panel into at least three regions. Three light guides for guiding the three colors of light to the first, second, and third regions, respectively, so that the three colors of light are emitted, the color separation optical system, and the three light guides An optical path switching means provided between the light guide means and the light guide means, wherein the light guide means to which each of the three colors of light is incident is cyclically switched between the three light guide means while synchronizing with the video signal. Optical path switching means for switching the color of light applied to each of the first, second, and third regions, and the first, second, and third portions of the color image
A liquid crystal that drives the liquid crystal panel in synchronization with a switching operation by the optical path switching unit based on the video signal so that an image corresponding to the color of light applied to each area is simultaneously displayed by the liquid crystal panel. Panel driving means.

According to the first invention, the light from the light source is color-separated into three colors, and different positions on the liquid crystal panel are simultaneously irradiated with the three colors of light. By moving the display in synchronization with the image display position on the panel, it is possible to increase the efficiency of use of light from the light source, and to provide a high-brightness color image display even on an image display device using a single liquid crystal panel. it can. Also, unlike conventional video display devices using a single liquid crystal panel, there is no need for dedicated display pixels for red display, green display, and blue display. One-third of the liquid crystal panel used may be sufficient, which is advantageous in terms of cost.

In a second aspect based on the first aspect, the optical path switching means comprises a support structure having an axially symmetrical shape, and three light guide paths penetrating the support structure.
It has three pairs of entrances and exits that allow light of the colors to enter, and when any of the three colors of light enters from one of the entrances and exits in each light guide path, the incident light is reflected by the entrances and exits. Three light guide paths arranged so as to be incident on any of the three light guide means from the other of the three, and a rotation drive means for rotating the support structure about a symmetry axis of the support structure;
Rotation control for controlling the rotation driving means based on the video signal so that light incident on each light guide means from each light guide path is cyclically switched between the three colors of light in synchronization with the video signal. Means.

According to the second aspect of the present invention, the optical path switching means can be realized by a simple configuration in which three light guide paths of optical fibers or the like are incorporated in an axially symmetric structure such as a cylindrical or polygonal column, so that the size is reduced. And lighter,
There is no need for a high-output motor or the like (drive source) as the rotation drive means. Therefore, it is possible to suppress an increase in cost and an increase in the size of the apparatus due to the introduction of the optical path switching mechanism.

In a third aspect based on the first aspect, the liquid crystal panel comprises a plurality of scanning signal lines respectively corresponding to horizontal scanning lines in an image represented by the video signal, and the plurality of scanning signal lines. A plurality of video signal lines intersecting with each other, and a liquid crystal display pixel unit provided at each intersection of the plurality of scanning signal lines and the plurality of video signal lines, the liquid crystal panel driving means Dividing each horizontal scanning period in the video signal into first, second, and third periods, and converting three color signals obtained from the video signal as color signals respectively corresponding to the three colors of light into the first Horizontal scanning side driving means for applying to the video signal line during the first, second and third periods, and one driving unit for each horizontal scanning period in each of the first, second and third regions Scan signal lines sequentially A vertical scanning side driving unit for generating a scanning signal to be selected, and three scanning signal lines to be selected within the same horizontal scanning period in the first, second and third regions by the scanning signal. Irradiation is performed on a region including the scanning signal line selected from any of the first, second, and third periods without overlapping, and selected from the first, second, and third regions. The scanning is performed so that the color of the light is the same as the color of the color signal applied to the video signal line during the period when the scanning signal line is selected among the first, second, and third periods. Scanning signal correcting means for limiting the active period of the signal.

According to the third aspect, the first of the liquid crystal panels is
In the second and third regions, each of the three scanning signal lines to be selected within the same horizontal scanning period is selected one-third of one horizontal scanning period without overlapping each other, and The color of light applied to an area including a scanning signal line selected from the second and third areas and the first and
A signal is applied to each scanning signal line so that the color corresponding to the color signal applied to the video signal line during the period when the scanning signal line is selected in the second and third periods is matched. . As a result, the images corresponding to the colors of the light radiated to the first, second, and third regions, respectively, are simultaneously displayed on the liquid crystal panel, so that the color image represented by the video signal is obtained.

According to a fourth aspect of the invention, a plurality of pre-stage optical paths and a plurality of post-stage optical paths are connected between the plurality of pre-stage optical paths and the plurality of post-stage optical paths, and the respective pre-stage optical paths are connected. An optical path switching device for switching a rear optical path between the plurality of rear optical paths, a support structure having an axially symmetric shape, and a plurality of light guide paths penetrating the support structure, wherein It has a plurality of pairs of entrances and exits that allow the incidence of a plurality of outgoing lights, and when any one of the plurality of lights enters from one of the entrance / exit pairs in each light guide path, the incident light is the entrance / exit. A plurality of light guide paths arranged so as to be incident on any of the plurality of post-stage optical paths from the other of the pair; a rotation driving means for rotating the support structure about a symmetry axis of the support structure; From the optical path to each subsequent optical path And rotation control means for the light to control the rotation driving means to switch between said plurality of light,
It is characterized by having.

According to the fourth aspect of the present invention, a plurality of light paths are simultaneously switched by a simple configuration in which a plurality of light guide paths such as optical fibers are incorporated in an axially symmetric support structure such as a cylindrical or polygonal column. This eliminates the need for a high-output motor or the like (drive source) as the rotary drive means. Therefore, an optical path switching device that is reduced in size and weight can be realized. Such an optical path switching device can be used in fields such as optical communication in addition to the above-described video display device.

In a fifth aspect based on the fourth aspect, the front optical path and the rear optical path each include three optical paths, and the support structure has three light guide paths. It is characterized by.

In a sixth aspect based on the fourth aspect, the support structure has a plurality of optical fibers as the plurality of light guide paths.

According to a seventh aspect of the present invention, there is provided a single liquid crystal comprising at least three regions including first, second, and third regions to which light of three colors is irradiated while switching colors among the three colors. A driving method for driving the liquid crystal panel based on a video signal representing the color image in order to display a color image on a panel, wherein the liquid crystal panel is provided with horizontal scanning lines in an image represented by the video signal. A plurality of corresponding scanning signal lines, a plurality of video signal lines intersecting with each of the plurality of scanning signal lines, and at an intersection of the plurality of scanning signal lines and the plurality of video signal lines. And a liquid crystal display pixel unit provided respectively, wherein the driving method is configured such that each horizontal scanning period in the video signal is first,
Three color signals obtained from the video signal as color signals respectively corresponding to the three colors of light, divided into a number of periods equal to the number of the regions, including a second and a third period; Applying a video signal to a line during the first, second, and third periods, respectively, and scanning one line in each of the first, second, and third regions in each horizontal scanning period Generating a scanning signal for sequentially selecting signal lines; and causing each of the three scanning signal lines to be selected within the same horizontal scanning period in the first, second, and third regions by the scanning signal to each other. Irradiation is performed on a region including the scanning signal line selected from any of the first, second, and third periods without overlapping, and selected from the first, second, and third regions. Light color and the first, A scanning signal selecting step of limiting an active period of the scanning signal so that a color of a color signal applied to the video signal line coincides with a period during which the scanning signal line is selected among the second and third periods. And a scanning signal applying step of applying a scanning signal having a limited active period to the scanning signal line.

According to the seventh aspect, red, green, and blue images are simultaneously displayed independently in at least three regions in a single liquid crystal panel, and the color of the image displayed in each region is the same. Is switched according to the color of the light radiated to. Therefore, 3 obtained by color separation of the light from the light source
A color image can be displayed by simultaneously using the light of the colors. For this reason, the utilization efficiency of light from a light source can be improved, and a bright color image can be obtained in a video display device using a single liquid crystal panel.

[0019]

Embodiments of the present invention will be described below with reference to the accompanying drawings. <1. FIG. 1 is a plan view showing a configuration of a video display device according to an embodiment of the present invention.
Is a side view showing the same configuration. This video display device
A lamp 11 as a light source of white light, a reflecting mirror 12 for efficiently collecting the light from the lamp 11, a condenser lens 13 for condensing the light, and a light, red, green, and blue light from the lamp 11 First and second dichroic mirrors 14r and 14b for decomposing the primary color light, and first to fourth reflecting mirrors 15r1, 15r2, 15b1 and 15 for guiding the primary color light.
b2, a liquid crystal panel 20 for displaying an image, an optical path switching unit 21 for switching an optical path until light beams of three primary colors reach the liquid crystal panel 20, and a light path switching unit 21 for transmitting light beams of three primary colors from the light path switching unit 21 to the liquid crystal panel. And first to third illumination light guide paths 22 a, 22 b, and 22 c for guiding to the liquid crystal panel 20.
, A motor 32 for rotating the optical path switching unit 21, and a motor rotation control unit 33 for rotating the motor 32 in synchronization with a video signal Sv supplied from the outside. It has.

<2. Configuration and Operation of Each Part of Embodiment>
With reference to FIG. 1 and FIG. 2, the operation of the video display device according to the present embodiment will be described together with the detailed configuration of each unit. Lamp 1
The white light W from 1 passes through the condenser lens 13 directly or after being reflected by the reflecting mirror 12, and enters the first and second dichroic mirrors 14r and 14b. First
And the second dichroic mirrors 14r and 14b
They are arranged so that they are perpendicular to each other and the incident angles of the white light W after passing through the condenser lens 13 are both 45 degrees. The first dichroic mirror 14r reflects a red light component of light incident thereon and transmits other light. The second dichroic mirror 14b reflects the blue light component of the light incident thereon and reflects other light. The red light R reflected by the first dichroic mirror 14r is guided to the optical path switching unit 21 by the first reflecting mirror 15r1 and the second reflecting mirror 15r2, and from a predetermined first position to the optical path switching unit. 21. Second
Blue light B reflected by the dichroic mirror 14b
Is guided to the optical path switching unit 21 by the third reflecting mirror 15b1 and the fourth reflecting mirror 15b2, and enters the optical path switching unit 21 from a predetermined second position. The first and second dichroic mirrors 14r, 1 of the white light W
The light transmitted through 4b becomes green light G. This green light G
Is incident on the optical path switching unit 21 from a predetermined third position.

The light of the three primary colors of red, blue, and green obtained by decomposing the white light W in this manner is transmitted to the optical path switching unit 21.
From the first to third positions. Here, the first and second dichroic mirrors 1 are arranged such that the three directions when the light of the three primary colors respectively enter the optical path switching unit 21 from the first to third positions are separated by 120 degrees.
4r, 14b and first to fourth reflecting mirrors 15r1, 15r2, 1
The positional relationship between 5b1 and 15b2 and the optical path switching unit 21 is set.

The optical path switching section 21 includes a support structure and first to third light guides 25a, 25b, and 25c, which are three types of optical waveguides penetrating the support structure.
The support structure has a cylindrical or polygonal columnar axially symmetric shape (in the present embodiment, the support structure is assumed to be cylindrical), and is rotated by the motor 32 about the axis of symmetry. Each of the light guide paths 25a, 25b, and 25c has a pair of entrances and exits on the side surface of the support structure, and light of three primary colors guided to the first to third positions respectively enters the three systems of light guide paths. Each light guide path 25a, 25b, 25c is arranged in the support structure so that light can be incident simultaneously from the three entrances / exit which is one of the exit pairs. Each light guide path 25a, 25b, 2
The primary color lights R, G, and B incident on the optical path switching unit 21 from one of the entrance / exit pair 5c are guided to the exit which is the other of the entrance / exit pair according to the incident light guide path.

The three illumination light guide paths 22a to 22c are respectively connected to the light guide paths 25a and 25
an entrance having a size corresponding to each of the entrances and exits b and 25c, and an exit having a size corresponding to each of the first to third regions obtained by dividing the liquid crystal panel 20 into three in the vertical scanning direction. have. And three illumination light guide paths 2
The entrances 2a to 22c face the three exits (entrance / exit) of the optical path switching unit 21 at predetermined rotation positions in close proximity to each other,
In addition, the three illumination light guide paths 22a to 22c are arranged such that the emission ports of the three illumination light guide paths 22a to 22c face the first to third regions in the liquid crystal panel 20, respectively.
c is arranged. In the example shown in FIG. 1, in the optical path switching unit 21, the red light R is transmitted to the first light guide 25a, the green light G is transmitted to the second light guide 25b, and the blue light B is transmitted to the third light guide 25c. At the time of incidence, the entrance of the first illumination light guide 22a is located near the exit of the first light guide 25a,
The entrance of the second illumination light guide 22b is near the exit of the second light guide 25b, the entrance of the third illumination light guide 22c is near the exit of the third light guide 25c, Each exists. Therefore, in this case, the primary color lights R, G, and B that have passed through the optical path switching unit 21 are converted into the first to third illumination light guide paths 2.
2a, 22b, and 22c, respectively, and the liquid crystal panel 21 is illuminated by the illumination light guide paths 22a, 22b, and 22c.
To the first to third regions of the liquid crystal panel 21. In the following, the first to third regions are defined as an upper 1/3 region (hereinafter simply referred to as "upper") and a central 1/3 region when the liquid crystal panel 20 is divided into three equal parts in the vertical scanning direction. Area (hereinafter simply referred to as “central part”), lower 1/3 area (hereinafter simply referred to as “lower part”)
It is assumed that Therefore, in the example shown in FIG.
The upper, middle, and lower portions of the liquid crystal panel 21 are illuminated with red light R, green light G, and blue light B, respectively.

Incidentally, since the optical path switching section 20 is configured to be rotated by the motor 32, the motor 32
With the rotation of, the colors of the light rays incident on the illumination light guide paths 22a to 22c are sequentially switched. On the other hand, the emission ports of the illumination light guide paths 22 a to 22 c are arranged at positions fixed to the liquid crystal panel 20. Therefore, the portions illuminated by the red light, the green light, and the blue light on the liquid crystal panel 20 sequentially move in accordance with the rotation of the optical path switching unit 20.

The motor 32 is controlled by a motor rotation control unit 33 so as to rotate in synchronization with the video signal Sv. The liquid crystal panel 20 displays images for each primary color from the illumination light guide paths 22a to 22c. It is driven by the liquid crystal panel drive unit 31 so as to correspond to the color of the illumination light. That is, the switching of the color of the light illuminating the first to third regions of the liquid crystal panel 20 and the switching of the color of the primary color images respectively displayed in the first to third regions by the liquid crystal panel 20 are synchronized. Thus, the rotation control of the motor 32 and the driving of the liquid crystal panel 20 are performed.

In the image display apparatus as described above, the light guide paths 25a to 25c and the illumination light guide paths 22a to 22c in the light path switching unit 21 are means for freely changing the direction of light, such as an optical fiber. Can be implemented using

<3. Operation of Optical Path Switching Unit> Next, the operation of the optical path switching unit 21 will be described in detail with reference to FIGS. As described above, the light path switching unit 21 is provided with three systems of light guide paths 25a to 25c, and each of the primary color lights R and R separated by the dichroic mirrors 14r and 14b into three colors.
G and B have an angle of 120 degrees with respect to each other.
Incident on 1. When the optical path switching unit 21 is rotated by the motor 32 in synchronization with the video signal Sv, the optical paths of the primary color lights R, G, and B are switched. At this time, the state of the optical path switching unit 21 is determined by the motor 32 rotating the optical path switching unit 21 by 120 degrees, as shown in FIGS.
A cyclic transition is made between the three states shown in FIG. Here, FIG. 3A shows that the red light R passes through the first light guide path 25a,
The optical path switching unit 21 is located at a rotational position (hereinafter referred to as a “0 degree position”) where green light G enters the second light guide path 25b and blue light B enters the third light guide path 25c. . FIG. 3B shows that the red light R is applied to the second light guide path 25b.
The green light G enters the third light guide path 25c and the blue light B enters the first light guide 25c.
The optical path switching unit 21 is located at a rotational position where the light enters the light guide path 25a, that is, a position rotated by 120 degrees clockwise from the 0 degree position (hereinafter referred to as a “120 degree position”). . FIG. 3C shows that the red light R is in the third light guide 25c and the green light G is in the first light guide 25a.
At a rotational position where the blue light B is incident on the second light guide path 25b, that is, a position rotated 240 degrees clockwise from the 0 degree position (hereinafter referred to as a “position at 240 degrees”). The optical path switching unit 21 is shown.

As shown in FIG. 3A, at the position of 0 degree,
The red light R passes through the first light guide 25a to enter the first illumination light guide 22a, and the green light G passes through the second light guide 25b to enter the second illumination light guide 22b, and the blue light B is the third
And enters the third illumination light guide path 22c through the light guide path 25c. As described above, the first to third illumination light guide paths 22a to 22c exit ports are arranged to illuminate the upper, middle, and lower portions of the liquid crystal panel 20, respectively. Therefore, at the 0-degree position, the upper, middle, and lower portions of the liquid crystal panel 20 are illuminated with red light R, green light G, and blue light B, respectively, as shown in FIG.

Next, when the optical path switching unit 21 is rotated to the position of 120 degrees, the red light R, the green light G, and the blue light B are respectively supplied to the third illumination as shown in FIG. Light guide path 22
c, first illumination light guide 22a, second illumination light guide 22b
Incident on. Therefore, as shown in FIG. 4B, the upper, middle, and lower portions of the liquid crystal panel 20 are respectively
It is illuminated with green light G, blue light B, and red light R.

Further, when the optical path switching unit 21 rotates to the position of 240 degrees, as shown in FIG.
The green light G and the blue light B are respectively transmitted to the second illumination light guide path 2.
2b, third illumination light guide 22c, first illumination light guide 22
a. Therefore, as shown in FIG.
The upper, middle, and lower portions of the liquid crystal panel 20 are illuminated with blue light B, red light R, and green light G, respectively.

As described above, by rotating the optical path switching section 21 in synchronization with the video signal Sv, the liquid crystal panel 2 is rotated.
The liquid crystal panel 20 can be simultaneously illuminated with each of the color lights R, G, and B while the portions illuminated by the red light R, the green light G, and the blue light B on the 0 are moved in the vertical scanning direction. The optical path switching unit 21 includes a cylindrical or polygonal column-shaped axially symmetric structure having an optical fiber or the like having three light guide paths.
Since it has a simple configuration incorporated in a system, it can be reduced in size and weight, and does not require a high-output motor 32 as a driving unit of the optical path switching unit 21.

As described above, according to the present embodiment, the upper, middle, and lower portions of the liquid crystal panel 20 are three primary color lights R, G, and B obtained by decomposing the light from the lamp 11 into three primary colors. Since each can be illuminated simultaneously, the light utilization efficiency is higher than that of a conventional video display device that displays images of three primary colors in a time-divided manner (approximately three times that of a conventional video display device).

<4. Detailed Configuration of Liquid Crystal Panel Driving Unit> Next, the configuration of the liquid crystal panel driving unit 31 in the video display device according to the present embodiment will be described in detail. In the following, the liquid crystal panel 20 includes a plurality of scanning signal lines each corresponding to a horizontal scanning line in an image represented by the video signal Sv, and a plurality of video signal lines intersecting each of the plurality of scanning signal lines. And a liquid crystal display pixel portion as pixel forming means provided at each intersection of the plurality of scanning signal lines and the plurality of video signal lines. Each liquid crystal display pixel portion is a portion for forming each pixel of a color image displayed by the liquid crystal panel 20, and includes, for example, a thin film transistor (TFT) and a transparent electrode corresponding to one pixel. And a liquid crystal portion sandwiched between the transparent electrodes. The gate of the TFT is connected to a scanning signal line passing through the intersection corresponding to the TFT, one of a source and a drain of the TFT is connected to a video signal line passing through the intersection corresponding to the TFT, and the other is connected to the opposite side. Are connected to one of the transparent electrodes. The other of the opposing transparent electrodes is grounded. Then, when a scanning signal line passing through an intersection corresponding to a certain liquid crystal display pixel portion is selected, when a video signal is applied to a video signal line passing through the intersection,
When the value of the video signal is written to the liquid crystal display pixel portion as a pixel value, and then the scanning signal line is deselected, the pixel value is changed until the next scanning signal line is selected. It is held in the pixel section.

FIG. 5 shows the configuration of the liquid crystal panel drive section 31 in the video display device according to the present embodiment,
FIG. 2 is a block diagram shown together with the configuration of FIG. The liquid crystal panel drive unit 31 in the present embodiment generates a drive signal for displaying a color image on the liquid crystal panel 20 illuminated with light of each primary color based on the video signal Sv as described above. The liquid crystal panel drive unit 31 includes a color demodulation circuit 71,
The red video signal processing circuit 72a, the green video signal processing circuit 72b, the blue video signal processing circuit 72c, the video signal switching circuit 73, the synchronization signal separating circuit 74, the liquid crystal panel drive control circuit 75, the vertical Scan signal control circuit 76
, A horizontal scanning driver circuit 53, a red vertical scanning driver circuit 55a, a green vertical scanning driver circuit 55b, a blue vertical scanning driver circuit 55c, and first to third vertical scanning signal switching circuits 57a to 57c. And Further, the liquid crystal panel driving unit 3 having such a configuration is used.
1 is driven by the liquid crystal panel 2
0, the first, the upper, the middle and the lower
To the third scanning signal lines 56a to 56c and the video signal line 54
And first to third liquid crystal display pixel portions 52a to 52c corresponding to three intersections of the first to third scanning signal lines 56a to 56c and the video signal line 54, respectively. Here, for simplicity of explanation, the number of horizontal scanning lines, that is, the number of scanning signal lines is set to 3, and only one video signal line 54 will be described.

A video signal Sv is input from the outside to the liquid crystal panel drive section 31, and the video signal Sv is supplied to a color demodulation circuit 71 and a synchronization signal separation circuit 74. The color demodulation circuit 71 decomposes the video signal Sv into red, green, and blue primary color signals Sr, Sg, Sb, and those primary color signals Sr, Sb
g and Sb are given to a red video signal processing circuit 72a, a green video signal processing circuit 72b, and a blue video signal processing circuit 72c, respectively. Video signal processing circuits 72a, 72 for each color
b and 72c are the red, green and blue primary color signals S
r, Sg, and Sb are respectively converted into a format for display on the liquid crystal panel 20, and the converted signal is converted into the driving primary color signal S.
Output as dr, Sdg, and Sdb, respectively. The video signal switching circuit 73 is a circuit that selects any one of the driving primary color signals Sdr, Sdg, and Sdb and supplies the selected driving primary color signal to the horizontal scanning driver circuit 53 as the driving primary color signal Sdv. The signal Sdv is supplied to the vertical scanning signal control circuit 76.
Are switched among the three driving primary color signals Sdr, Sdg, and Sdb in accordance with the video switching control signal Ssw generated in step (1).

The synchronization signal separation circuit 74 separates the horizontal synchronization signal Hsync and the vertical synchronization signal Vsync from the video signal Sv.
These synchronization signals Hsync and Vsync are output to the liquid crystal panel drive control circuit 75. The liquid crystal panel drive control circuit 75
Based on the horizontal synchronization signal Hsync and the vertical synchronization signal Vsync, a first control signal for driving the liquid crystal panel 20 is used.
To generate the third control signals C1, C2, C3. The first control signal C1 is sent to the horizontal scanning driver circuit 53, and the second control signal C2 is sent to the vertical scanning driver circuits 55a to 55c for each color.
55c, the third control signal C3 is input to the vertical scanning signal control circuit 76, respectively.

The horizontal scanning driver circuit 53 generates a driving video signal to be applied to each video signal line in the liquid crystal panel 20 based on the driving primary color signal Sdv selected by the video signal switching circuit 73 and the first control signal C1. Generate The driving video signal is a signal for determining the value of each pixel on each horizontal scanning line in an image to be displayed by the liquid crystal panel 20. Hereinafter, as described above, one video signal line 54 corresponding to one pixel on each horizontal scanning line (hereinafter, this video signal line is referred to as a “video signal line of interest”) and the video signal line 54 of interest are applied. The following description focuses on the driving video signal Sd.

The vertical scanning driver circuit 55 for each color
a, 55b, 55c are based on the second control signal C2,
A scanning signal for causing the liquid crystal panel 20 to display an image of each color is generated. That is, the red vertical scanning driver circuit 55a generates red scanning signals SR1 to SR3 for vertical scanning for causing the liquid crystal panel 20 to display a red image. The green vertical scanning driver circuit 55b generates green scanning signals SG1 to SG3 for vertical scanning for causing the liquid crystal panel 20 to display a green image. The blue vertical scanning driver circuit 55c generates blue scanning signals SB1 to SB3 for vertical scanning for causing the liquid crystal panel 20 to display a blue image. The scanning signals SR1 to SR3, SG1 to SG3, and SB for each color generated in this manner.
Among the first to SB3, the first color scanning signal group including the red scanning signal SR1, the green scanning signal SG1, and the blue scanning signal SB1 is a first vertical scanning signal switching circuit 57a.
And the red scanning signal SR2 and the green scanning signal S
The second color scanning signal group composed of G2 and the blue scanning signal SB2 is input to the second vertical scanning signal switching circuit 57b, and the red scanning signal SR3, the green scanning signal SG3, and the blue scanning signal SB3. Are input to a third vertical scanning signal switching circuit 57c.

The vertical scanning signal control circuit 76 generates the above-mentioned video switching signal Ssw based on the third control signal C3, and also controls the vertical scanning switching control signal Scr for red and the vertical scanning switching control signal Scg for green described later. And a blue vertical scanning switching control signal Scb. Here, the video switching control signal Ssw
In the horizontal scanning period of the video signal Sv, the three driving primary color signals Sdr, Sdg, and Sdb are sequentially switched one by one for each one-third of one horizontal scanning period.
Is a control signal to be selected. The vertical scanning switching control signals Scr, Scg, Scb for each color correspond to the selection of each driving primary color signal Sdr, Sdg, Sdb by the video switching control signal Ssw in each horizontal scanning period of the video signal Sv. Is a signal that is activated every １ ／ of one horizontal scanning period. The vertical scanning switching control signals Scr, Scg, Scb for each color are input to the vertical scanning signal switching circuits 57a to 57c.

The first vertical scanning signal switching circuit 57a generates a first scanning signal line based on the first scanning signal groups SR1, SG1, SB1 for each color and the vertical scanning switching control signals Scr, Scg, Scb for each color. A first drive scanning signal Ssa to be applied to 56a is generated. Second vertical scanning signal switching circuit 57b
Is a second driving scanning signal to be applied to the second scanning signal line 56b based on the second scanning signal groups SR2, SG2, SB2 for each color and the vertical scanning switching control signals Scr, Scg, Scb for each color. Generate Ssb. The third vertical scanning signal switching circuit 57c includes a third scanning signal group for each color SR3, SG3, S
A third drive scanning signal Ssc to be applied to the third scanning signal line 56c is generated based on B3 and the vertical scanning switching control signals Scr, Scg, Scb for each color. As already mentioned,
The first to third scanning signal lines 56a, 56b, 56c are arranged at the upper, middle, and lower portions of the liquid crystal panel 20, respectively.

<5. Operation of Liquid Crystal Panel Driving Unit> Next, the operation of the liquid crystal panel driving unit 31 configured as described above will be described. In the above description, the number of horizontal scanning lines (scanning signal lines) is set to 3 for simplicity of description, but in the following, m scanning signal lines are arranged in each of the upper, middle, and lower portions of the liquid crystal panel 20. It is assumed that That is, in the above configuration, the red vertical scanning driver circuit 55a outputs SR11 to SR1m instead of SR1 and SR21 to SR2m instead of SR2 as red scanning signals.
SR31 to SR3m are output instead of SR3.
The green vertical scanning driver circuit 55b outputs SG11 to SG1m instead of SG1 as green scanning signals.
However, SG21 to SG2m are output instead of SG2, and SG31 to SG3m are output instead of SG3. From the blue vertical scanning driver circuit 55c, SB11 to SB1m instead of SB1, SB21 to SB2m instead of SB2, and SB31 to SB3m instead of SB3 as blue scanning signals.
Are respectively output. Corresponding to this, hereinafter, first vertical scanning signal switching circuit groups 57a1 to 57am replace first vertical scanning signal switching circuit 57a, and the first vertical scanning signal switching circuit 57b replaces second vertical scanning signal switching circuit 57b. Two vertical scanning signal switching circuit groups 57b1 to 57bm replace the third vertical scanning signal switching circuit 57c with the third vertical scanning signal switching circuit group 57c1.
５７57 cm are provided respectively. Therefore, in this case, the liquid crystal panel 20 includes first scanning signal line groups 56a1 to 56am instead of the first scanning signal lines 56a.
Are provided with second scanning signal line groups 56b1 to 56bm in place of the second scanning signal lines 56b, and third scanning signal line groups 56c1 to 56cm in place of the third scanning signal lines 56c, respectively.
Further, first liquid crystal display pixel unit groups 52a1 to 52am are substituted for the first liquid crystal display pixel unit 52a, and second liquid crystal display pixel unit groups 52b1 to 52bm are substituted for the second liquid crystal display pixel unit 52b.
Are replaced with third liquid crystal display pixel units 52c, respectively, and third liquid crystal display pixel unit groups 52c1 to 52cm are provided. The first scanning signal line groups 56a1 to 56am include first driving scanning signal groups Ssa1 to Ssam generated by the first vertical scanning signal switching circuit groups 57a1 to 57am, and the second scanning signal line groups. In 56b1 to 56bm, second driving scanning signal groups Ssb1 to Ssbm generated by the second vertical scanning signal switching circuit groups 57b1 to 57bm are provided, and in the third scanning signal line groups 56c1 to 56cm, third vertical scanning signal groups 56c1 to 56cm are provided. Scanning signal switching circuit group 5
Third drive scanning signal groups Ssc1 to Sscm generated by 7c1 to 57cm are applied, respectively. The first
Scanning signal line groups 56a1 to 56am and first liquid crystal display pixel section groups 52a1 to 52am are provided in the upper part of the liquid crystal panel 20, and second scanning signal line groups 56b1 to 56bm and second liquid crystal display pixel section groups 52b1 to 52bm. Are located in the middle of the liquid crystal panel 20, the third scanning signal line groups 56c1 to 56cm and the third liquid crystal display pixel group 52c1 to 52cm are located in the liquid crystal panel 20.
, Are arranged at the lower part.

FIG. 6 is a timing chart for explaining the vertical scanning operation in the liquid crystal panel driving section 31 under the above-described premise. As shown in FIG.
垂直 of the size of the liquid crystal panel 20 in the vertical scanning direction
So that the liquid crystal display pixel part at the position shifted by
A scanning signal is output from each color vertical scanning driver circuit 55a to 55c. For example, when the number of display lines (the number of horizontal scanning lines) in the vertical scanning direction of the liquid crystal panel 20 is 480 (when m = 160), the first scanning signal line 56a1 of the liquid crystal panel 20 is selected. As described above, when the scanning signal SR11 is output from the red vertical scanning driver circuit 55a (when the scanning signal SR11 is active), the 161st scanning signal line 56b1 of the liquid crystal panel 20 is output.
Is selected so that the green vertical scanning driver circuit 55 is selected.
b outputs the scanning signal SG21 (becomes active), and outputs the scanning signal SB31 from the blue vertical scanning driver circuit 55c so that the 321st scanning signal line 56c1 of the liquid crystal panel 20 is selected (active and active). Become). Then, each time one horizontal scanning period of the video signal Sv ends, the vertical scanning driver circuits 55a, 55b, and 55 for the respective colors are selected so that the scanning signal line at the next position is selected.
The scanning signal is output from 5c.

This is so that the liquid crystal display pixel portions having the same relative position in the vertical scanning direction in the upper, middle, and lower portions of the liquid crystal panel 20 are simultaneously selected.
In addition, the scanning signals are output from the vertical scanning driver circuits 55a to 55c for each color so that the scanning signal line at the next position is selected each time one horizontal scanning period of the video signal Sv ends. means. Here, which of the upper, middle, and lower regions of the liquid crystal panel 20 the vertical scanning driver circuits 55a to 55c select the scanning signal line depends on the switching of the optical path by the optical path switching unit 21. For example, when the optical path switching unit 21 is at the position of 0 degrees as shown in FIG.
The upper, middle, and lower portions of the liquid crystal panel 20 are illuminated with red light R, green light G, and blue light B, respectively, as shown in FIG.
At this time, the red vertical scanning driver circuit 55a activates the scanning signal SR1j so that the scanning signal line 56aj (j is any one of 1 to m) is selected above the liquid crystal panel 20, and the green vertical scanning driver 55a. The circuit 55b activates the scanning signal SG2j so that the scanning signal line 56bj is selected in the middle part of the liquid crystal panel 20, and the blue vertical scanning driver circuit 55c selects the scanning signal line 56cj below the liquid crystal panel 20. The scanning signal SB3j is activated as described above (see FIGS. 6B, 6F, and 6J). on the other hand,
When the optical path switching unit 21 is at the position of 120 degrees as shown in FIG. 3B, the upper, middle and lower portions of the liquid crystal panel 20 are green light G and blue light, respectively, as shown in FIG. B, illuminated with red light R. At this time, the green vertical scanning driver circuit 55b activates the scanning signal SG1j so that the scanning signal line 56aj (j is any one of 1 to m) is selected above the liquid crystal panel 20, and the blue vertical scanning driver 55b. The circuit 55c activates the scanning signal SB2j so that the scanning signal line 56bj is selected in the center of the liquid crystal panel 20, and operates the red vertical scanning driver circuit 55a.
Activates the scanning signal SR3j so that the scanning signal line 56cj is selected below the liquid crystal panel 20 (FIG. 6).
(See (c), (g) and (h)).

Next, the horizontal scanning operation in the liquid crystal panel driving section 31 will be described with reference to FIG. As described above, the primary color signals Sr, Sg, Sb are output from the color demodulation circuit 71.
The video signal separated into the video signals is supplied to the video signal processing circuit 72 for each color.
The format is converted into a format for displaying an image on the liquid crystal panel 20 in a to 72c. At this time, the video signal processing circuit 7 for each color
2a to 72c output three color video signals at three times or more the speed of normal horizontal scanning in order to write three color video signals of red, green and blue to the liquid crystal panel during one horizontal scanning period. . Then, based on the video switching control signal Ssw from the vertical scanning signal control circuit 76, the video signal switching circuit 73
By switching the video signal to be selected among the three-color video signals Sdr, Sdg, and Sdb output at three times or more the speed of normal horizontal scanning, the three-color video signals Sdr, Sdg, and Sdb are output.
Are generated in a time-division multiplexed manner to generate a video signal Sdv. This signal Sdv is input to the horizontal scanning driver circuit 53 as a serial multiplexed video signal. Horizontal scanning driver circuit 5
No. 3 performs scanning at three times or more the normal speed in order to complete the scanning of the video signal of each color in 1/3 of one horizontal scanning period. That is, three color video signals (color signals) Sdr, S
The multiplexed video signal Sdv, which is a serial signal obtained by time-division multiplexing of dg and Sdb, is subjected to serial-to-parallel conversion, and a signal indicating the value of each pixel in each horizontal scanning line is output for each of three colors.
It is applied to each video signal line at intervals of 1/3 of the horizontal scanning period. More specifically, as shown in FIGS. 7A and 7B, the horizontal scanning driver circuit 53 controls the first control signal C
1, each horizontal scanning period is temporally divided into first to third periods, and the multiplexed video signal S
Based on the dv, signals representing the red image, the green image, and the blue image in the first to third periods, respectively (FIG. 7)
(B)) is generated for each video signal line, and this is applied to the corresponding video signal line 54 as the driving video signal Sd.

As shown in FIGS. 7C to 7E, the vertical scanning signal control circuit 76 controls the red vertical scanning switching control signal S
cr is a signal that is active (for example, H level) only in a first period that is the first one-third of each horizontal scanning period, and a vertical scanning switching control signal Scg for green is used as the next one in each horizontal scanning period. The blue vertical scanning switching control signal Scb is a signal that becomes active only during the second period of the third period.
Is output as a signal that is active only in the third period, which is the last one-third of each horizontal scanning period. First to third vertical scanning signal switching circuit groups 57a1 to 57a
am, 57b1 to 57bm, and 57c1 to 57cm, the vertical scanning switching control signals Scr, Scg, and Scr for each color are respectively the scanning signal from the red vertical scanning driver circuit 55a and the green vertical scanning driver circuit 55b. The logical product of the scanning signal and the scanning signal from the blue vertical scanning driver circuit 55c is obtained.

Therefore, during the first period of each horizontal scanning period, that is, the period when the red video signal is output from the horizontal scanning driver circuit 53 by each vertical scanning signal switching circuit, the red vertical scanning driver circuit 55a outputs the signal. Can be output to the scanning signal line of the liquid crystal panel 20. Here, for example, if the scanning signal SR11 from the red vertical scanning driver circuit 55a is active, this scanning signal SR11 is output to the vertical scanning signal switching circuit 57.
a1 through the first period (the first ３ of one horizontal scanning period)
Is output to the scanning signal line 56a1 for only the period of the liquid crystal display pixel section 5 in the upper part of the liquid crystal panel 20.
2a1 is written.

During the second period of each horizontal scanning period, that is, the period when the green video signal is output from the horizontal scanning driver circuit 53 by the vertical scanning signal switching circuit, the signal from the green vertical scanning driver circuit 55b is output. The scanning signal can be output to the scanning signal line of the liquid crystal panel 20. Here, for example, if the scanning signal SG21 from the green vertical scanning driver circuit 55b is active, this scanning signal SG21 passes through the vertical scanning signal switching circuit 57b1 for the second period (one next to one horizontal scanning period). (Period of / 3) is output to the scanning signal line 56b1, and the green video signal is written to the liquid crystal display pixel portion 52b1 in the middle part of the liquid crystal panel 20.

Further, during the third period of each horizontal scanning period, that is, the period when the blue video signal is output from the horizontal scanning driver circuit 53 by the vertical scanning signal switching circuit, the signal from the blue vertical scanning driver circuit 55c is output. The scanning signal can be output to the scanning signal line of the liquid crystal panel 20. Here, for example, if the scanning signal SB31 from the blue vertical scanning driver circuit 55c is active,
The scanning signal SR31 passes through the vertical scanning signal switching circuit 57c1 and is output to the scanning signal line 56c1 only for the third period (the last ３ period of one horizontal scanning period). The liquid crystal display pixel section 52c1 in the lower part
Is written to.

As described above, in the present embodiment, the video signals of the respective primary colors are input to the horizontal scanning driver circuit 53 in a time-division multiplexed state. A driving video signal representing a video and a blue video in a time-division manner by 1/3 of one horizontal scanning period is applied to a video signal line. On the other hand, the vertical scanning driver circuits 55a, 55b, 55c for each color
In one of the three regions (upper, middle, and lower) of the above, one of the scanning signal lines is selected in a region to be irradiated with light of a color corresponding to the vertical scanning driver circuit (hereinafter referred to as “applicable color”). , Generate a scanning signal. Then, the vertical scanning signal switching circuit to which the scanning signal is input is based on a vertical scanning switching control signal corresponding to the corresponding color,
The active period of the scanning signal is limited to 1/3 of one horizontal scanning period so that the scanning signal line is selected only during the period when the driving video signal from the horizontal scanning driver circuit 53 represents a video of the corresponding color. I do. In this manner, the value of the video signal corresponding to the color of the light applied to the region including the liquid crystal display (either the upper, middle, or lower) is written in each liquid crystal display of the liquid crystal panel 20. By this, each primary color light applied to the liquid crystal panel 20 is spatially modulated, so that a color image represented by the video signal Sv is displayed.

<6. Effects of the Embodiment> As described above, according to the present embodiment, the liquid crystal panel 2 uses the three primary color lights R, G, and B as the illumination light from the lamp 11 separated into the three primary colors.
Since the upper, middle, and lower portions at 0 are simultaneously illuminated (see FIG. 4), the light use efficiency is higher than that of a conventional video display device that displays a video of three primary colors in a time-division manner. Further, by switching the optical paths of the primary color lights R, G, and B by the optical path switching unit 21 in synchronization with the video signal Sv, the color of light illuminating each area (upper, middle, and lower) in the liquid crystal panel 20 becomes three. The liquid crystal panel 20 is driven so that the primary colors are sequentially switched and that the respective regions of the liquid crystal panel 20 simultaneously display images of the three primary colors. Therefore, according to the present embodiment, a color image can be displayed on a single liquid crystal panel while maintaining high light use efficiency. Furthermore, like a conventional image display device using a single liquid crystal panel,
Since dedicated display pixels for red display, green display, and blue display are not required, the number of pixels may be 1/3 of the liquid crystal panel used in the conventional video display device. Therefore, a sufficiently bright color image can be provided while avoiding an increase in cost and an increase in the size of the apparatus. According to the present embodiment, the optical path switching unit 21 has a simple configuration in which three systems of light guides such as optical fibers are incorporated into a cylindrical or polygonal support structure, and can be reduced in size and weight. Therefore, an increase in cost and an increase in the size of the apparatus due to the introduction of the optical path switching mechanism can be suppressed.

<7. Modifications> The liquid crystal panel drive unit 31 in the present embodiment is configured using three vertical scanning driver circuits respectively corresponding to three primary colors, but the present invention is not limited to such a configuration. Instead, for example, instead of the three vertical scanning driver circuits 55a to 55c, one vertical scanning driver circuit that generates a scanning signal so that three scanning signal lines are simultaneously selected may be used.

In the above embodiment, in order to divide each image of the three primary colors spatially and display them at the same time, three regions (upper and middle portions) obtained by dividing the liquid crystal panel 20 into three in the vertical scanning direction are used. , Lower part) correspond to the three primary colors, respectively, but the division for setting the area to correspond to the three primary colors is not limited to the vertical direction. For example, the left area, the center area, and the right area, which are three areas obtained by dividing the liquid crystal panel 20 into three parts in the horizontal scanning direction, are three.
You may make it correspond to each primary color. In this case, the exits of the three illumination light guide paths 22a to 22c are configured and arranged so as to face the three regions, that is, the left region, the center region, and the right region, respectively,
8A to 8C according to the rotation position of the optical path switching unit 21.
The liquid crystal panel 20 is illuminated with light of three primary colors as shown in FIG. In this case, the video signal processing circuits 72a, 72a for each color are applied so that the video signal of each primary color corresponding to the area division in the horizontal scanning direction is applied to the video signal line of the liquid crystal panel 20.
72b and 72c output driving primary color signals Sdr, Sdg and Sdb, respectively, and a video signal switching circuit 73 selects one of these driving primary color signals Sdr, Sdg and Sdb to select a horizontal scanning driver circuit 53. It becomes the composition supplied to.
In this case, the vertical scanning driver circuit may be configured to output a scanning signal such that only one scanning signal line is selected and the selected scanning signal lines are sequentially switched. However, according to the color change of the light applied to each part (the left area, the center area, and the right area) of the liquid crystal panel 20 (FIGS. 8A to 8C), three pixels are set in each vertical scanning period of the video signal Sv. A scanning signal is applied to a scanning signal line of the liquid crystal panel 20 so that vertical scanning is performed every time.

Further, the division of the liquid crystal panel 20 for spatially dividing the respective images of the three primary colors and displaying them simultaneously is not limited to three divisions.
May be divided into three or more regions. For example, the liquid crystal panel 20 is divided into first to sixth regions, and the first to sixth regions are divided.
First, red, green, blue, red, green, and blue may be respectively assigned to the regions, and each color assigned to each region may be sequentially switched.

As can be seen from the above description, the present invention is applicable not only to a video display device using a transmission type liquid crystal panel but also to a video display device using a reflection type liquid crystal panel.

[Brief description of the drawings]

FIG. 1 is a plan view showing a configuration of a video display device according to an embodiment of the present invention.

FIG. 2 is a side view showing the configuration of the video display device according to the embodiment.

FIG. 3 is a diagram for explaining an operation of switching the optical path of each primary color light by the optical path switching unit in the embodiment.

FIG. 4 is a view for explaining an illumination state on a liquid crystal panel in the embodiment.

FIG. 5 is a block diagram showing a configuration of a liquid crystal panel driving unit in the embodiment together with a configuration of the liquid crystal panel.

FIG. 6 is a timing chart for explaining a vertical scanning operation of the liquid crystal panel drive unit in the embodiment.

FIG. 7 is a timing chart for explaining a horizontal scanning operation of the liquid crystal panel drive unit in the embodiment.

FIG. 8 is a view for explaining an illumination state on a liquid crystal panel in a modification of the embodiment.

FIG. 9 is a block diagram showing a configuration of a conventional video display device using one liquid crystal panel.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 ... Lamp 14r, 14b ... Dichroic mirror 15r1, 15r2, 15b1, 15b2 ... Reflecting mirror 20 ... Liquid crystal panel 21 ... Optical path switching part 22a-22c ... Illumination light guide path 25a-25c ... Light guide path 31 ... Liquid crystal panel drive part 32 ... Motor 33 ... Motor rotation control units 52a to 52c ... Liquid crystal display pixel unit 53 ... Horizontal scan driver circuit 54 ... Video signal line 55a to 55c ... Vertical scan driver 56a to 56c ... Scan signal line 57a to 57c ... Vertical scan signal switching circuit 73 ... Video signal switching circuit 75 Liquid crystal panel drive control circuit 76 Vertical scanning signal control circuit W White light R Red light G Green light B Blue light Sv Video signal Sdr, Sdg, Sdb Drive primary color signal Sd Driving video signals Scr, Scg, Scb ... vertical scanning switching control signals SR1 to SR3 ... red driving Signal SG1 to SG3 ... green scanning signal SB1 to SB3 ... blue scanning signal Ssa ... first driving scanning signal Ssb ... second driving scanning signal Ssc ... third driving scanning signal

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (Reference) H04N 9/30 G02F 1/1335 530 F-term (Reference) 2H041 AA18 AA21 AB21 AC04 AZ01 2H091 FA05Z FA23Z FA26Z FA41Z GA13 LA13 LA15 2H093 NA16 NA43 NA65 NC09 NC11 NC16 NC34 NC43 ND08 ND17 ND49 ND54 NE06 5C060 AA07 BA04 BA09 BB13 BC05 DB01 EA01 HC21 HD05 JA00

Claims (7)

[Claims] 1. A video display device for displaying a color image represented by a video signal by transmitting light or reflected light obtained by irradiating a single liquid crystal panel driven based on a color video signal with light. A light source that emits white light; a color separation optical system that separates the white light into light of three colors of red, green, and blue; and a first light-emitting device that is obtained by dividing the liquid crystal panel into at least three regions. Three light guides for guiding the three colors of light to the first, second, and third regions, respectively, such that the three colors of light are applied to the second and third regions, respectively; An optical path switching means provided between the decomposing optical system and the three light guiding means, wherein the light guiding means to which each of the three colors of light is incident is connected between the three light guiding means by the video signal. Switching cyclically while synchronizing with With this, an optical path switching unit that switches the color of light emitted to each of the first, second, and third areas, and the first, second, and third areas of the color image are respectively emitted to the first, second, and third areas. Liquid crystal panel driving means for driving the liquid crystal panel in synchronization with the switching operation by the optical path switching means based on the video signal so that an image corresponding to the color of the light is simultaneously displayed by the liquid crystal panel. An image display device comprising: 2. The optical path switching means comprises: a support structure having an axially symmetrical shape; and three light guide paths penetrating the support structure, and three pairs of light that enable the light of the three colors to enter. When one of the three colors of light is incident from one of the pair of entrances and exits in each light guide path, the incident light is transmitted to one of the three light guides from the other of the pair of entrances and exits. Three light guide paths arranged so as to be incident on the optical axis; rotation driving means for rotating the support structure about a symmetry axis of the support structure; and light incident on each light guide means from each light guide path. 2. A rotation control unit that controls the rotation driving unit based on the video signal so as to cyclically switch between three colors of light in synchronization with the video signal. 3. The video display device according to 1. 3. The liquid crystal panel, comprising: a plurality of scanning signal lines each corresponding to a horizontal scanning line in an image represented by the video signal; and a plurality of video signals intersecting each of the plurality of scanning signal lines. And a liquid crystal display pixel portion provided at each of the intersections of the plurality of scanning signal lines and the plurality of video signal lines, wherein the liquid crystal panel driving unit performs each horizontal scanning period in the video signal. It is divided into first, second, and third periods, and three color signals obtained from the video signal as color signals respectively corresponding to the three colors of light are respectively divided into the first, second, and third periods. A horizontal scanning side driving unit applied to the video signal line; and a scanning signal for sequentially selecting one scanning signal line for each horizontal scanning period in each of the first, second, and third regions. Vertical to generate A scanning-side driving unit; and the first, second and third scanning signal lines to be selected within the same horizontal scanning period in the first, second, and third regions by the scanning signal do not overlap with each other. The color of the light that is selected in any of the second and third periods and is irradiated to the region including the scanning signal line selected from the first, second, and third regions and the first color A scan that limits an active period of the scan signal so that a color of a color signal applied to the video signal line coincides with a period during which the scan signal line is selected among the second and third periods. The video display device according to claim 1, further comprising: signal selection means. 4. A plurality of front-stage optical paths and a plurality of rear-stage optical paths are connected between the plurality of front-stage optical paths and the plurality of rear-stage optical paths. An optical path switching device for switching between a plurality of subsequent optical paths, comprising: a support structure having an axially symmetric shape; and a plurality of light guide paths penetrating the support structure, the plurality of light paths being emitted from the plurality of front optical paths. It has a plurality of pairs of entrances and exits that allow the incidence of light, and when any of the plurality of lights is incident from one of the entrance and exit pairs in each light guide path, the incident light is from the other of the entrance and exit pairs. A plurality of light guide paths arranged so as to be incident on any of the plurality of post-stage optical paths; a rotation driving means for rotating the support structure about a symmetry axis of the support structure; and a post-stage from each light guide path The light incident on the optical path is The number of the optical path switching device, characterized in that it comprises a rotation control means for controlling the rotation driving means to switch between the light. 5. The optical system according to claim 4, wherein the first optical path and the second optical path each include three optical paths, and the support structure includes three optical waveguides. Optical path switching device. 6. The optical path switching device according to claim 4, wherein a plurality of optical fibers are arranged on the support structure as the plurality of light guide paths. 7. A color image is formed on a single liquid crystal panel including at least three regions including first, second, and third regions irradiated with light of three colors while switching colors among the three colors. A driving method for driving the liquid crystal panel based on a video signal representing the color image, so that the liquid crystal panel includes a plurality of liquid crystal panels each corresponding to a horizontal scanning line in an image represented by the video signal. Scanning signal lines,
A plurality of video signal lines intersecting with each of the plurality of scanning signal lines, and a liquid crystal display pixel unit provided at each intersection of the plurality of scanning signal lines and the plurality of video signal lines. The driving method may divide each horizontal scanning period in the video signal into a number of periods equal to the number of the regions, including first, second, and third periods, and correspond to the three colors of light, respectively. A video signal applying step of applying three color signals obtained from the video signal as color signals to the video signal line during the first, second, and third periods, respectively; Generating a scanning signal for sequentially selecting one scanning signal line for each horizontal scanning period in each region of the third region; and performing the same horizontal scanning in the first, second, and third regions by the scanning signal. Within the scanning period Are selected in any of the first, second, and third periods without overlapping each other, and the first, second, and third regions are not selected. And the color of light applied to a region including the selected scanning signal line, and the color applied to the video signal line during the period in which the scanning signal line is selected among the first, second, and third periods. A scanning signal selecting step of limiting the active period of the scanning signal so that the color of the color signal matches the scanning signal, and a scanning signal applying step of applying the scanning signal having the limited active period to the scanning signal line. A method for driving a liquid crystal panel, comprising: