JPH11271709A - Display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the display device which is free of a color breakup and has high display quality. SOLUTION: This device is equipped with an image display part 2 consisting of plural CRTs 1 which are so arrayed in matrix as to constitute successive display areas and can have their frame frequencies controlled independently and a liquid crystal color shutter 30 which is arranged on the display areas and switches the wavelength of transmitted light at a switching frequency synchronizable with the frame frequencies of images displayed on the display areas. Display characteristics which are stable after driving is started can be obtained by selecting the display frequency according to electrooptic response characteristics of the liquid crystal color shutter 30 based upon operation temperature condition, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a field sequential type color image display device, and more particularly to a color image display device comprising a group of liquid crystal color light shutters and a plurality of monochrome image display devices arranged on a plane. It relates to a driving method.

[0002]

2. Description of the Related Art Display devices using liquid crystals are lightweight, thin,
Due to its characteristics such as low power consumption, it is applied to various fields such as OA equipment, information terminals, clocks, and televisions. In particular, a liquid crystal display element using a thin film transistor element or the like as a switching element is used for a monitor for displaying data including a lot of information such as a portable television and a computer due to its responsiveness.

[0003] Since an increase in the amount of information requires an increase in display colors, a liquid crystal display device generally has three colors of RGB.
By providing a color filter that transmits color,
Many color displays are possible. This color filter has three colors of R, G, and B, which are arranged in a plane and divided in a plane.
GB (red, green, blue), RGBB (red, green, blue, black), R
A unit pixel is composed of several picture elements such as GBW (red, green, blue, and white), which causes a reduction in resolution and luminance. Further, there is a problem that a high technology for arranging different colors for each fine pixel is required, so that the manufacturing unit price is increased and the price of the entire liquid crystal display device is increased.

On the other hand, multi-color information display by a field-sequential operation type color shutter display system (field sequential system) in which time-division color display is performed in accordance with an image signal generated by emission of a white light source and the human eye recognizes the color image as a color image. There is a device. This display device is a black-and-white display high-definition C
A shutter that controls the transmission of light of three primary colors, such as RBG and YCM, is provided in front of the RT or LCD, and color images are time-divisionally combined by plane-sequential operation. The resolution depends only on the black-and-white display device provided on the back. This is a new display method. In this method, a liquid crystal element is used as a color shutter for controlling transmission and non-transmission of three primary colors. This liquid crystal color shutter generally includes a combination of several color polarizing elements, two liquid crystal elements, and a neutral polarizing element, and changes the direction of linear polarization oscillation of light passing through the liquid crystal layer by 90 °. Light transmission control of three primary colors is performed.

If the image display device using a white light source is a high-definition CRT, there is a concern that the thickness of the CRT will increase as the size increases and the thickness of the entire image display device will increase. A method of reducing the thickness of the entire image display device by increasing the size of the image display device (multi-CRT array method) is also being studied.

A liquid crystal color shutter system for selecting a transmission wavelength by a birefringence effect has also been proposed (JP-A-6-89083, Casio Computer Co., Ltd.). this is,
This is a color shutter system in which one liquid crystal element is inserted between two polarizing elements to select a transmission wavelength by an applied voltage. Generally, an ECB (electrically-carrying) method is used.
This is a method referred to as “controlled birefringence (voltage-controlled birefringence mode)”. By using such a method, a member such as a color polarizing plate becomes unnecessary, so that an inexpensive shutter configuration can be realized.

However, in the ECB mode, the transmission wavelength is selected in a state where a voltage is applied, that is, in a state where the liquid crystal molecules rise from the substrate surface at a certain angle due to the voltage, so that the margin of the driving voltage is narrow. There is a problem. Further, the influence of the driving temperature is large, and it is necessary to provide a feedback circuit and a sensor for controlling the driving temperature. Further, since a high-speed response is required for the shutter element, it is common to use a display method showing a relatively high-speed response, such as a Pi array structure, among nematic liquid crystals, but this method is applied from the outside. The response at the time of applying a voltage, which is a force, is as fast as several hundred μsec, but the response when the voltage is turned off is uniquely determined from the energy stable state determined by the liquid crystal molecule alignment and the liquid crystal molecule alignment state. For this reason, the response is delayed from 1 msec to several msec. As a liquid crystal system showing a faster response, a shutter using an FLC or AFLC element has been attempted, but alignment stability, temperature dependency, and the like.
From the viewpoint of the manufacturing process, a large shutter element has not been constructed yet. In particular, the operation speed dependency of the liquid crystal color shutter due to a change in humidity and the color breakup phenomenon when displaying a moving image are important problems that degrade the display quality.

[0008]

Conventionally, FLC and AFL
In a field-sequential display comprising a color shutter using a high-speed liquid crystal such as C, the driving frequency is changed from 3 times the normal to 6 to 9 times from the viewpoint of high-speed response such as FLC material to display a moving image or the like. Attempts have been made to reduce color breakup due to the movement of the subject, but on the other hand, there has been a problem such as deterioration in display quality due to changes in the response speed of the liquid crystal shutter due to temperature changes. In addition, there is a problem that the influence of the increase in the wiring resistance and the writing capacity due to the enlargement of the pixel electrode area of the shutter element accompanying the increase in size and the increase in the time constant due to these increases cannot be ignored.

The present invention has been made to solve such a problem. That is, the present invention provides an image display device having an optimized display quality by controlling the frame frequency and switching time of a monochrome display device and a color shutter element by using a liquid crystal color shutter and a monochrome display device arranged in a plane. It is to provide.

[0010]

In order to solve such a problem, the display device of the present invention has the following configuration.

The first aspect of the display element of the present invention is as follows.
A plurality of display elements arranged in a matrix and independently controllable in frame frequency, and disposed on the display area and transmitted at a switching frequency that can be synchronized with a frame frequency of an image displayed in the display area. A liquid crystal color shutter for switching a wavelength of light, a unit for detecting a response speed of the liquid crystal color shutter, and a unit for adjusting a frame frequency of the display element or a switching frequency of the liquid crystal color shutter according to the detected response speed. , Are provided. This display device improves the display quality by detecting the operation state of the liquid crystal color shutter and adjusting the frame frequency of the display element or the drive frequency of the liquid crystal color shutter according to the detected operation state.

The plurality of display elements may be arranged so that a display area is continuous. Further, the display area of the display element has a first area and a second area, and the liquid crystal color shutter can control the switching frequency independently in the first area and the second area. There is a feature.

[0013] A second aspect of the display element of the present invention is as follows.
A plurality of display elements arranged in a matrix so as to form a display area including a first area and a second area and capable of independently controlling a frame frequency; And a liquid crystal color shutter capable of switching the wavelength of the first region and the second region at an independent switching frequency.

Further, the display device of the present invention is a field-sequential type comprising a plurality of independent display elements arranged in a matrix in a plane and a liquid crystal color shutter arranged on a display screen constituted by the plurality of display elements. In the display device, a frame frequency of the display element and a switching frequency (time) of a liquid crystal color shutter synchronized with the frame frequency are both variable.

The display device further includes a plurality of display elements arranged so as to form a continuous display area, and a liquid crystal color shutter arranged in the display area. It is characterized in that it is variable over the entire surface or a part of the display area.

[0016] Further, among the display elements and the liquid crystal color shutters arranged in a matrix, the driving frequency of a predetermined area can be arbitrarily changed.

Further, one of the electrode structures of the liquid crystal color shutter may be divided into a shape which can be synchronized with a frame scanning direction of the display element.

Further, a response speed of the liquid crystal color shutter is detected by a temperature sensor provided in the liquid crystal color shutter, and a driving frame frequency of the display element can be adjusted according to the detected response speed. You may.

For example, in a moving image display in which information of an image displayed by the display element changes every few frames or every frame, the liquid crystal color shutter is driven at n times the normal frame frequency to fix the character information. In a still image display for displaying as an image, the liquid crystal color shutter may be driven at 3 to 6 times the normal frame frequency.

As the display element, for example, a thin CRT having a multi-CRT array structure in which small CRTs are arranged in a plane so as to form a continuous display area can be used. Each CRT displays an image using an independent electron gun. Therefore, each independent CR
The frame frequency on the T display screen can be independently controlled by the scanning speed of each electron gun.

On the other hand, as the liquid crystal color shutter, AFLC, FLC, stacked Pi cells, and the like having high response speed (both voltage response time τ _rise and response recovery time τ _decay are 0.3 msec or less) are used.

As the substrate holding the liquid crystal material, for example, a glass substrate or a plastic film substrate (polyethylene terephthalate, PES, PEN, polycarbonate, etc.) through which visible light can pass can be used. If necessary, a hybrid substrate composed of a glass substrate and a plastic substrate may be used.

As a constituent material of the electrode provided on the liquid crystal layer sandwiching surface of the substrate, for example, ITO (I
ndium Tin Oxide), conductive polyaniline, polypyrrole, or the like can be used, but it is preferable to use ITO which absorbs little visible light. For electrode patterning, wet etching is possible with ITO, but oxygen plasma asher or the like is used with organic polyaniline or polypyrrole.

The electrode structure for applying a voltage to the liquid crystal material includes an X electrode group divided into a plurality of parts in a direction parallel to the scanning direction of the CRT, and a Y electrode provided on a counter substrate.

The number of divisions of the X-electrode is
The RT screen is preferably divided into at least three parts (to correspond to three primary colors such as RGB and CMY), and it is more preferable to further increase the number of divisions in order to increase the frame frequency.

The liquid crystal color shutter is provided with a sensor for monitoring a change in response speed due to a temperature change or the like. By feeding back a response speed measurement result by applying a test signal, a monochrome (gray) color is displayed in the display area. (Scale) The frame frequency of the CRT for performing the display may be optimized. In particular, when the operating environment temperature is around 0 ° C., it is preferable to drive the frame frequency at about three times (180 Hz), but the setting can be changed depending on the liquid crystal material used.

On the other hand, the image information displayed in the display area formed by the display element is stored in advance in the frame memory for several frames, and is compared with the information in the front and rear memories to determine whether the display information is fast moving or moving image information. It is preferable to determine whether the image is a small still image and optimize the frame frequency of the CRT and the switching time of the color shutter element synchronized with the frame frequency.

The driving frequency is automatically controlled by the display information, but it is also possible to fix the driving frequency to a constant value by manual operation depending on the use condition.

[0029]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the display device of the present invention will be described in more detail.

(Embodiment 1) FIG. 1 is a diagram schematically showing an example of the configuration of a display device of the present invention. This display device is a field-sequential type display device capable of displaying a color image, and includes a plurality of display elements 1 arranged in a matrix so as to form a continuous display area and capable of independently controlling a frame frequency. An image display unit 2 comprising:
A liquid crystal color shutter 30 is provided on the display area and switches the wavelength of transmitted light at a switching frequency that can be synchronized with the frame frequency of an image displayed in the display area. The image display unit 2 is configured by arranging small CRTs 1 capable of individually displaying images individually in a matrix in a plane so as to form a continuous display area.
The liquid crystal color shutter 30 includes shutter elements 3 and 4 using a liquid crystal layer as a light valve, a neutral polarizer 5 and color polarizers 7 and 8. For example, the color deflecting plate 7 may control light of C and R, and the color deflecting plate 8 may control light of M and Y.

FIG. 2 is a diagram for explaining the scanning direction of the image display unit. As shown in FIGS. 2A and 2B, the CRTs 1 arranged in a matrix form a scanning direction for each of the patterns 9 sequentially scanned from top to bottom and the regions corresponding to the color shutter electrode divided regions. Scanning is performed by the pattern 10 to be changed. Since each CRT has an electron gun, it is possible to display an image at an independent scanning speed.

FIG. 3 is a view for explaining the structure of the shutter elements 3 and 4 constituting the liquid crystal color shutter 30. The shutter elements 3 and 4 each have a liquid crystal layer sandwiched between two light-transmitting substrates. Electrodes for applying an electric field to the liquid crystal layer to obtain an electro-optical response are provided on the liquid crystal layer sandwiching surface of the substrate. In this electrode, a transparent electrode group 11 is formed in the X-axis direction so as to correspond to rows 1a, 1b, and 1c of the CRT 1 arranged in a matrix. Further, the transparent electrode 11 divided corresponding to the CRT screen is constituted by the electrode 12 divided into three in parallel with the scanning direction.

Further, by dividing and arranging the electrodes 11 and 12 in one row of the display element array, the switching frequency of the liquid crystal color shutter can be independently adjusted and driven in different portions of the display area. .

On the other hand, a common electrode 13 of a solid pattern having a region covering the entire surface of the electrode groups 11 and 12 is formed on the substrate surface opposed to the electrode groups 11 and 12. Waveforms having different driving frequencies are applied. FIG. 4 is a diagram schematically showing an example of the configuration of the display device of the present invention. A CRT drive signal control circuit 14 that drives the image display unit 2 detects a signal from a response speed measurement sensor 15 attached to the shutter elements 3 and 4 that constitute the liquid crystal color shutter 30, and generates an image according to the detected response speed. A display signal is supplied by optimizing the frame frequency of the display unit 2. Note that the sensor 15a is preferably disposed in a portion having the slowest response speed, for example, in the vicinity of the center of the long side, of the shutter elements 3 and 4 constituting the liquid crystal color shutter 30. 5 and 6 are diagrams for explaining the operation of the display device of the present invention.

In general, when the power is turned on, the characteristics of the display element 1 and the shutter elements 3 and 4 are unstable. Therefore, as shown in FIG. 5, character information with little change in information can be displayed stably. In a moving image having a large change in information, an image is easily broken due to a difference between a shutter switching speed and a CRT frame frequency. In the present invention, the response speed of the shutter elements 3 and 4 is detected, and the switching frequency of the liquid crystal color shutter 30 is adjusted in accordance with the detected response speed. , The image quality can be prevented from lowering. Then, as shown in FIG. 6, when the temperature of the shutter element having the liquid crystal layer is stabilized by the CRT operation and the response speed change obtained by the response speed measurement sensor is reduced, or the change of the display information is reduced by the frame memory or the like. If there is a lot of moving image information detected, set the frame frequency to 6
Switch to 9x speed and LCD color shutter 3
By increasing the switching speed of 0 (for example, 6 times speed or 9 times speed), the quality of moving image display can be improved.

FIG. 7 is a diagram schematically showing another example of the configuration of the display device of the present invention. As shown in FIG. 7, when a still image such as character information with little information change and a moving image with large information change are mixed in the display area of the display device, the CRT drive signal circuit 14 uses the normal triple speed. The frame frequency region 18 and the 6 to 9 × speed frame frequency region 20 corresponding to a moving image are independently controlled, and the normal switching speed region 19 and the high speed switching region 21 of the shutter are synchronized with the frame frequency region 18 and the liquid crystal color shutter driving circuit and the scanning electrode side driving. Each is controlled by the frequency conversion circuit 17. Due to the kinking, the power consumption in the character information area can be reduced and the display quality in the moving image display area can be improved.

As described above, according to the present invention, by selecting the display frequency in accordance with the characteristics of the electro-optical response of the liquid crystal color shutter depending on the operating temperature conditions, it is possible to obtain stable display characteristics after the start of driving. . In addition, the quality of the moving image display is improved by partially selecting the drive frequency according to the display image information, and the increase in the power consumption due to the increase in the drive frequency is reduced by performing the drive divided into regions. be able to.

(Embodiment 2) The display device of the present invention described in Embodiment 1 was actually produced.

As the image display unit 2, a multi-CRT array in which small CRTs 1 are arranged in a matrix in a plane is used. The display area of the image display unit 2 is 32 inches diagonally, and small CRTs arranged in a matrix of 3 × 3 and 8 × width are used.

The structure of the liquid crystal color shutter 30 is as follows. Multi C on a 32 inch diagonal glass substrate
A substrate on which strip-shaped electrodes made of ITO patterned in the X-axis direction with a width of about 1 cm so that the division of each CRT display surface of the RT array and the division position of the shutter electrode coincide with each other; On a glass substrate surface having a display size of 32 inches diagonally for lamination facing each other, an electrode made of ITO in a solid pattern was provided.

A polyimide for liquid crystal alignment film (Nippon Synthetic Rubber Co., Ltd .:
Optomer AL-1051) was formed by offset printing at a thickness of about 40 nm. Approximately 1
After baking and drying at 80 ° C. for about 1 hour, a rubbing treatment was performed by a conventional method for the purpose of controlling the alignment direction of the liquid crystal. At this time, the rubbing phrase is 18 on each substrate surface.
Rubbing treatment was performed so as to form an angle of 0 ° ± 10 °.

While a sealant is formed using a dispenser in a non-display area around the display area, a silica spacer (thin ball: 2 μm) having a diameter of 2 μm is formed on the opposing substrate surface.
m) was dispersed by, for example, an electrostatic spraying method, and the substrates were brought into close contact with each other while maintaining a predetermined gap.

A ferroelectric liquid crystal material (FELIX018: manufactured by hoechst Japan) is injected into this gap by a vacuum injection method.
Was injected to form a liquid crystal cell serving as the shutter elements 3 and 4. By combining the second shutter element, the cyan and red polarizers 7, the magenta and yellow polarizers 8, and the neutral polarizers 5, the three color shutter operations of RGB can be performed. The liquid crystal color shutter 30 was configured. Then, a field-sequential color image display device was obtained by a configuration in which the display area of the multi-CRT array as the image display section and the display area of the liquid crystal color shutter were arranged so as to overlap each other.

The driving circuit of the CRT 1 and the driving circuit of the liquid crystal color shutter 30 have a circuit structure designed to be synchronized with each other, and the operation state from the response speed measuring sensor 15 provided in the shutter elements 3 and 4. Is detected at any time. The sensor unit 15a of the response speed sensor 15 is configured by a photocurrent-voltage conversion circuit combining a general photodiode and a high-speed operational amplifier. The response speed is roughly estimated based on a light change speed at the time of switching of a liquid crystal color shutter, and a CRT drive circuit is provided. By applying the feedback to the LCD color shutter drive circuit, it was possible to control to optimize the display quality.

Comparative Example 1 A multi-CRT array in which small CRTs were arranged in a matrix in a plane was used as a monochrome display element. Display area is 32 inches diagonal and small CRT
Were arranged in a vertical x3 and horizontal x8 configuration. The configuration of the color shutter element is as follows. A glass substrate having a diagonal width of 32 inches and ITO patterned with a width of 1 cm in the X-axis direction so that the division of each CRT display image of the multi-CRT array and the division position of the shutter electrode coincide with each other. Diagonal 32 for laminating opposite
A solid ITO electrode was provided on a glass substrate surface having an inch display size. Polyimide for a liquid crystal alignment film (Nippon Synthetic Rubber Co., Ltd .: Optmer AL-1051) was applied with a thickness of 40 nm by offset printing to the surface of each substrate surface in contact with the liquid crystal material. After baking and drying at 180 ° C. for 1 hour, a rubbing treatment was performed by a conventional method for the purpose of controlling the alignment direction of the liquid crystal. At this time, the rubbing process was performed so that the rubbing directions formed an angle of 180 ° ± 10 ° on each other. A cell was formed by applying a sealant to a non-display area using a dispenser while dispersing a silica spacer (silver ball: 2 μm) having a diameter of 2 μm on the opposing substrate surface and bringing the substrates into close contact with each other at a predetermined position. . Then, a ferroelectric liquid crystal material (FELIX018:
hoechst Japan) was injected to form a shutter element. A liquid crystal color shutter element capable of operating as a three-color RGB shutter was constructed by combining the second shutter element produced in the same manner with the cyan, magenta, yellow, and red polarizers and the neutral polarizer.

A field sequential type color image display device was obtained by a configuration in which the regions of the multi-CRT array and the color shutter element were arranged so as to overlap each other.

The driving circuit of the CRT and the liquid crystal color shutter driving circuit have a circuit configuration designed to be synchronized with each other, and are driven at a frame frequency of 6 to 9 times the speed.

(Embodiment 3) A multi-CRT array in which small CRTs are arranged in a matrix in a plane is used as a monochrome display element. The image display section 2 having a display area of 32 inches diagonally was configured by arranging small CRTs 1 in a matrix of 3 × 3 and 8 ×. The configuration of the liquid crystal color shutter 30 is as follows. A glass substrate having a diagonal width of 32 inches and ITO patterned with a width of 1 cm in the X-axis direction so that the division of each CRT display image of the multi-CRT array and the division position of the shutter electrode coincide with each other. A solid ITO electrode was applied to the surface of a glass substrate having a display size of 32 inches diagonally for opposing lamination. A polyimide for liquid crystal alignment film (Nippon Synthetic Rubber Co., Ltd .: Optmer AL-10) is provided on each substrate surface in contact with the liquid crystal material.
51) was applied with a thickness of 40 nm by offset printing. After baking and drying at 180 ° C. for 1 hour, a rubbing treatment was performed by a conventional method for the purpose of controlling the alignment direction of the liquid crystal.
At this time, the rubbing direction is 180 ° ±
Rubbing treatment was performed so as to form an angle of 10 °. A cell was formed by applying a sealant to a non-display area using a dispenser while dispersing a silica spacer (silver ball: 2 μm) having a diameter of 2 μm on the opposing substrate surface and bringing the substrates into close contact with each other at a predetermined position. .

Thereafter, a shutter element was formed by injecting a ferroelectric liquid crystal material (FELIX018: manufactured by hoechst Japan) by a vacuum injection method. A liquid crystal color shutter capable of operating as a three-color RGB shutter was constructed by combining the second shutter element produced in the same manner with the cyan, magenta, yellow, and red polarizers and the neutral polarizer.

A field sequential type color image display device was obtained by arranging the display area of the multi-CRT array and the display area of the liquid crystal color shutter so as to overlap each other.

The CRT drive circuit and the liquid crystal color shutter drive circuit have a circuit structure designed so as to be synchronized with each other, and detect the operation status from the response speed measurement sensors provided in the shutter elements 3 and 4 as needed. I do.

The response speed sensor is composed of a photocurrent-voltage conversion circuit combining a general photodiode and a high-speed operational amplifier. The response speed is roughly estimated based on the light change speed at the time of liquid crystal switching, and a CRT driving circuit and a liquid crystal color shutter driving circuit are used. Is controlled so as to optimize the display quality by applying feedback to.

FIG. 8 is a diagram schematically showing an example of the configuration of the display device of the present invention. FIG. 8A schematically shows an example of a mounting position of the sensor unit 15a, and FIG. 8B schematically shows an example of a configuration of the sensor unit 15b. The sensor unit 15a is constituted by a photocurrent-voltage conversion circuit combining a photodiode and a high-speed operational amplifier, and calculates the response speed of the shutter elements 3 and 4 constituting the liquid crystal color shutter 30 by changing the light speed at the time of liquid crystal switching. Then, the calculated response speed is used as the driving circuit 1 of the CRT 1 constituting the image display unit.
4 and a drive circuit for the liquid crystal color shutter. By employing such a configuration, the frame frequency of the image displayed on the image display unit or the switching frequency of the liquid crystal color shutter (for example, 3 × speed,
6 ×, 9 ×, etc.) can be adjusted according to the response speed of the liquid crystal color shutter. In particular, when the liquid crystal color shutter is driven at 9 × speed, it takes about 30 minutes for the electro-optical response of the liquid crystal to change from 10% to 90%.
It must be set to 0 μsec or less. For this reason, it is preferable to configure the sensor unit 15a using a light source having a wavelength of 600 nm or more, which has a relatively slow waveform.

Also, by providing a shift circuit in the scanning electrode, which can independently convert the driving signal to the scanning side electrode of the liquid crystal color shutter by the signal from the CRT driving circuit,
The switching frequency of the liquid crystal color shutter area corresponding to the RT row unit was controlled. (Comparative Example 2) Small CR
A multi-CRT array in which Ts were arranged in a matrix in a plane was used as a monochrome display element. The display area is 32 inches diagonally and a small CRT in which 3 × 8 small CRTs are arranged is used. The configuration of the color shutter element is as follows. A glass substrate having a diagonal width of 32 inches and ITO patterned with a width of 1 cm in the X-axis direction so that the division of each CRT display image of the multi-CRT array and the division position of the shutter electrode coincide with each other. A solid ITO electrode was applied to the surface of a glass substrate having a display size of 32 inches diagonally for opposing lamination. Polyimide for liquid crystal alignment film (Nippon Synthetic Rubber Co., Ltd .: Optmer AL-1051) having a thickness of 40 on the surface of each substrate surface in contact with the liquid crystal material.
nm by offset printing. 1 at 180 ° C
After baking and drying for a period of time, a rubbing treatment was performed by a conventional method for the purpose of controlling the orientation direction of the liquid crystal. At this time, the rubbing process was performed so that the rubbing directions formed an angle of 180 ° ± 10 ° on each other. A cell was formed by applying a sealant to a non-display area using a dispenser while dispersing a silica spacer (silver ball: 2 μm) having a diameter of 2 μm on the opposing substrate surface and bringing the substrates into close contact with each other at a predetermined position. . A ferroelectric liquid crystal material (FEL)
IX018: manufactured by hoechst Japan) to form a shutter element. A liquid crystal color shutter element capable of operating as a three-color RGB shutter was constructed by combining the second shutter element produced in the same manner with the cyan, magenta, yellow, and red polarizers and the neutral polarizer. A field sequential color image display device was obtained by a configuration in which the regions of the multi-CRT array and the color shutter element were arranged so as to overlap each other.

The drive circuit of the CRT and the liquid crystal color shutter drive circuit have a circuit structure designed to be synchronized with each other, and detect an operation state from a response speed measurement sensor provided in the shutter element as needed. The response speed sensor is composed of a photocurrent-voltage conversion circuit that combines a general photodiode and a high-speed operational amplifier.
The display quality is optimized by applying feedback to the RT drive circuit and the liquid crystal color shutter drive circuit. The scanning side electrodes were all set so as to be collectively driven by the liquid crystal color shutter drive circuit at the same switching frequency.

(Embodiment 4) Embodiment 2, Embodiment 3,
Display elements as in Comparative Examples 1 and 2 were actually created,
Each characteristic was compared.

In the device of Comparative Example 1, color breakage occurred in the display immediately after driving, and the reproduction of a moving image with extremely poor display quality was conspicuous. On the other hand, in the display devices of the present invention in the second and third embodiments, at the time of the initial driving, since the normal driving was performed at the triple speed, no color breakup was observed, and a stable moving image could be obtained. After the operation was stabilized, the switching frequency of the liquid crystal color shutter could be adjusted to 6 to 9 times the normal speed to drive. As a result, even in a fast-moving moving image, recognition of color breakup was small and display quality was good.

In the display device according to the second embodiment, the CRT
The power consumption of the driving circuit and the shutter element driving circuit was reduced by about 20% as compared with the display device of Comparative Example 2.

(Embodiment 5) FIG. 9 is a diagram schematically showing another example of the configuration of the display device of the present invention. A multi-CRT array in which small CRTs were arranged in a matrix in a plane was used as a monochrome display device. The display area is 32 inches diagonally and a small CRT in which 3 × 8 small CRTs are arranged is used.

The structure of the liquid crystal color shutter 30 is as follows. Multi C on a 32 inch diagonal glass substrate
An ITO-patterned substrate having a width of about 1 cm and patterned in the X-axis direction so that the division of each CRT display image of the RT array and the division position of the shutter electrode coincide with each other. A solid ITO electrode divided right and left was applied to a glass substrate surface having a display size of 32 inches square.

A polyimide for a liquid crystal alignment film (Nippon Synthetic Rubber Co., Ltd., Optmer AL-1051) having a thickness of 40 nm was applied to the surface of each substrate surface in contact with the liquid crystal material by offset printing.

Thereafter, after baking and drying at about 180 ° C. for 1 hour, a rubbing treatment was performed by a conventional method for the purpose of controlling the alignment direction of the liquid crystal. At this time, the rubbing process was performed so that the rubbing directions formed an angle of 180 ° ± 10 ° on each other.

Then, a sealant is applied to the non-display area around the display area by using a dispenser, and a silica spacer (silver ball: 2 μm) having a diameter of 2 μm is provided on the opposing substrate surface.
Were dispersed, and the substrates were brought into close contact with each other at predetermined positions to form a cell.

A ferroelectric liquid crystal material (FELIX 018:
hoechst Japan) was injected to form the shutter elements 3 and 4. By combining a second shutter element similarly manufactured with cyan, magenta, yellow, red polarizing plates and a neutral polarizing plate, R
A liquid crystal color shutter element capable of performing a GB color shutter operation was constructed. A field sequential color image display device was obtained by a configuration in which the regions of the multi-CRT array and the color shutter element were arranged so as to overlap each other.

The CRT drive circuit 14 and the liquid crystal color shutter drive circuit 16 have a circuit configuration so that they can be synchronized with each other. The operation state from the response speed measurement sensor 15 provided in the shutter elements 3, 4 is determined. Detect as needed.

In this example, the image display section 2 has display areas 2a and 2b where display is performed by independent display signals. The liquid crystal color shutter 30 can drive the areas 11a and 11b corresponding to the display areas 2a and 2b at independent switching frequencies. That is, the RX-Driver circuits 31 separately provided so that the drive signal to the scanning side electrode of the liquid crystal color shutter 30 can be independently controlled by the signal from the CRT drive circuit 14.
And a Y-Driver 33 on the counter electrode side corresponding to the drive frequency of each of the LX-Driver circuit 32 and RL.
Accordingly, the switching frequency of the liquid crystal color shutter 30 corresponding to the display area divided into the left and right of the image display unit 2 can be controlled independently (FIGS. 9A and 9A).
(B)).

By adopting such a configuration, in the display device of the present invention, for example, when a moving image is displayed in the display area 2a and character data or the like is displayed in the display area 2b, the liquid crystal color shutter is used. 30 can drive each region at an independent switching frequency. Therefore, display quality can be improved by preventing color breakage and the like. Further, since the switching frequency can be adjusted according to the display, power consumption can be reduced.

It is needless to say that the present invention is not limited to the embodiment described above, but can be variously modified and used within the scope of the invention.

[0069]

As described above, according to the display device of the present invention, the frame frequency of the image displayed in the display area of the image display unit and the switching frequency of the liquid crystal color shutter can be arbitrarily adjusted in synchronization. Can be. Therefore, a high-quality color image can be displayed according to, for example, an operating environment. In addition, by setting the frame frequency according to the form of the display image (image, text, etc.) and controlling the switching frequency of the liquid crystal color shutter in synchronization with this, high-quality moving image display and stable still image display are performed. Can be. Further, the power consumption can be reduced by increasing the frame frequency and the switching frequency only in the necessary area.

[Brief description of the drawings]

FIG. 1 is a diagram schematically illustrating an example of a configuration of a display device of the present invention.

FIG. 2 is a diagram illustrating a scanning direction of an image display unit.

FIG. 3 is a diagram for explaining a configuration of a shutter element included in a liquid crystal color shutter.

FIG. 4 is a diagram schematically showing an example of a configuration of a display device of the present invention.

FIG. 5 is a diagram illustrating an operation of the display device of the present invention.

FIG. 6 is a diagram illustrating an operation of the display device of the present invention.

FIG. 7 is a diagram schematically showing another example of the configuration of the display device of the present invention.

FIG. 8 is a diagram schematically illustrating an example of a configuration of a display device of the present invention.

FIG. 9 is a view schematically showing another example of the configuration of the display device of the present invention.

[Explanation of symbols]

 1 CRT 2 Image display area 2a Display area 2b Display area 3, 4 Liquid crystal cell 6, 7, 8 Polarizing plate 9, 10 ... CRT scanning pattern 11, 12... Transparent electrode 13... Opposite substrate electrode pattern 14... CRT drive signal circuit 15... Response speed measuring sensor 15a. Liquid crystal color shutter 17 Shutter division drive signal frequency conversion circuit 18 Triple speed drive character information area 19 Triple speed drive shutter area 20 Double speed drive moving image display Area 21: 9x speed shutter area 30: Liquid crystal color shutter

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI G02F 1/1343 G02F 1/1343 G09F 9/00 311 G09F 9/00 311Z 321 321E 322 322A G09G 3/18 G09G 3/18 3 / 20 680 3/20 680E H04N 9/30 H04N 9/30 (72) Inventor Tatsuo Saibu 33 Shinisogo-cho, Isogo-ku, Yokohama-shi, Kanagawa Prefecture Toshiba Production Engineering Research Laboratories Co., Ltd. 33, Shinisogo-cho, Isogo-ku, Yokohama-shi Inside Toshiba Production Technology Laboratory Co., Ltd.

Claims (2)

[Claims] 1. A plurality of display elements arranged in a matrix and capable of independently controlling a frame frequency, and arranged on the display area and synchronizable with a frame frequency of an image displayed in the display area. A liquid crystal color shutter that switches a wavelength of transmitted light at a switching frequency, a unit that detects a response speed of the liquid crystal color shutter, and a frame frequency of the display element or switching of the liquid crystal color shutter according to the detected response speed. A display device, comprising: means for adjusting a frequency. 2. A plurality of display elements which are arranged in a matrix so as to form a display area including a first area and a second area, and are capable of independently controlling a frame frequency; A display device, comprising: a liquid crystal color shutter that is provided and is capable of switching the wavelength of transmitted light between the first region and the second region at independent switching frequencies.