JPH06265852A - Liquid-crystal display of macroscopic size - Google Patents

Abstract

PURPOSE: To lower a price and to easily exchange pixels and switching elements by operationally arranging one of the plural individual pixels of a macroscopic size in respective sections stipulated by the space of two adjacent rows and columns. CONSTITUTION: A large-area liquid crystal display system 10 is black and white or all natural colors and is used so as to provide still or video images to the mass of the people positioned with a distance from the system 10. Then, the system 10 is provided with the almost rectangular supporting structure body 18 of a large area. On the structure body, a first address line set composed of X address lines including address lines 20, 22 and 24, a second address line set composed of Y address lines including the address lines 26, 28 and 30 and plural macroscopic size individual liquid crystal pixels (picture elements) 32, 34, 36, 38, 40, 42, 44, 46 and 48 are arranged. Further, the system 10 is also provided with the switching elements 50, 52, 54, 56, 58, 60, 62, 64 and 66 operationally combined with the respective macroscopic size liquid crystal pixels.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates generally to liquid crystal displays, and more specifically to large areas formed according to an array of macroscopically sized pixels or pixels so that the image may be viewed by many people. Involved in liquid crystal displays. In such a macroscopic liquid crystal display,
Examples include cinema screens, television projection screens, marquees or billboards.

[0002]

In the field of liquid crystal displays in general, and active matrix liquid crystal displays in particular, major international electronics companies have invested hundreds of millions of dollars over the last decade to characterize extremely high resolution. Has worked on the development of "large area" displays. As a result of these efforts,
To date, high resolution displays have been developed that are approximately the size of relatively small television sets. However, the electronic device manufacturer
In order to obtain a high resolution even in a diagonal 2, 3 or 5 inch liquid crystal display, X-defining the display
Thin film amorphous silicon transistors and diodes were used as switching elements to address the individual liquid crystal pixels of the Y matrix. Of course, as the size of the display increased, it became necessary to be able to address the number of rows and columns of the XY matrix defining the display. Also, in order to maintain the required resolution, the number of rows and columns of pixels must increase as the size of the display increases. However, increasing the number of rows and columns of pixels has resulted in another problem as to how to address each individual pixel of the display in order to periodically update the input signal at the video time rate.

[0003]

One of the main objects of the present invention
The first is to tackle problems that are directly opposed to the above problems. That is, the present invention aims to meet social and public needs by providing still and video image information to many people simultaneously in a single display system, rather than providing a very high resolution display. To aim. Such video information should be suitable for meeting the viewing requirements of a person, considering all factors such as distance from the display, viewing angle of the display, screen size, contrast and response. It is provided at the image level.

Another object of the present invention is to construct a liquid crystal display as described above using macroscopically sized liquid crystal pixels and switching elements. The pixels and switching elements used in the present invention are both easy to operate, easy to obtain and / or manufacture, inexpensive and easy to replace. Therefore, not only a large market is obtained, but also when the defective part needs to be replaced, the repair can be easily performed.

The objects and advantages of the invention will be apparent from the following summary of the invention, brief description of the drawings, examples and claims.

[0006]

The present invention relates to large area liquid crystal displays, such as billboards, cinema screens, television projection screens, etc., particularly suitable for viewing by a large number of people in public places. The display of the present invention comprises a substantially rectangular support structure that defines an XY matrix of substantially parallel rows and columns. The space between two adjacent rows and two adjacent columns both define an opening of a given shape. Each of these sections is operatively arranged with one of a plurality of macroscopic sized individual pixels. The shape of the pixel must match the shape of the partition. Both of these pixels have a large image area such that the information displayed therein is visible to the viewer and include liquid crystal display material operatively disposed between pixel electrodes. Importantly, the pixel has a size large enough to be manipulated by the display installer or repair person.
Also, a plurality of non-thin film type individual switching elements are electrically connected to the pixel so that the individual pixels surrounded by the rows and columns of the support structure can be addressed simultaneously.

Each pixel is preferably rectangular, especially square. The pixels should be sized and shaped to match the shape and size of the compartment above the support structure, ignoring the exact size and shape. Further, unlike the cathode ray tube, the depth (thickness) dimension of the pixel is made smaller than the length and width dimensions. In one of the preferred embodiments, the pixel has an image border of about 1 cm on a side. In a more preferred embodiment, the pixels have an image border of about 10 cm on a side. In the most preferred embodiment, the pixels have an image border of about 50 cm on a side or more.

The support structure further includes a plurality of spaced conductive X address lines and a plurality of spaced conductive Y address lines. In the most preferred embodiment, the individual switching element comprises a transistor having first, second and third terminals. A first terminal of each transistor is electrically connected to an X address line, a second terminal of each transistor is electrically connected to a Y address connection,
The third terminal of each transistor is electrically connected to the pixel electrode associated with the X and Y address lines.

For ease of connection and repair, each section of the matrix of the support structure is further engaged with a first and a second terminal of the transistor to connect these first and second terminals respectively. It also includes means for electrically connecting to the address lines and the Y address lines. Also, each individual large area pixel is
Means for engaging a third terminal of one of the individual transistors to electrically connect the third terminal to the first electrode of the pixel are also included. The second pixel electrode is electrically grounded.

In another preferred embodiment of the invention, diodes may be used as the plurality of individual switching elements. If diodes are used, two diodes are combined with each pixel and they are interconnected in an anode to cathode relationship. More specifically, the cathode of the first diode is electrically connected to the first X address line and the anode of the second diode is electrically connected to the adjacent X address line.
The pixel electrode is electrically connected to a common node formed between the two diodes. The support structure itself preferably comprises means for electrically connecting the cathode of the first diode to the first X address line and the anode of the second diode to the adjacent X address line.

A pin connector is provided in one of the compartments or the switching elements on the support structure, and a socket connector is provided in the other so that the socket connector can be electrically engaged with the pin connector. . Both the pixels and the switching elements are sized for manual mounting and electrical connection to the compartments on the support structure.

Also, an approximately V-shaped elongated lens (known as a butterfly lens) is operatively placed at the periphery of each macroscopic size pixel to obtain a coherent image over the entire length and width of a large area display. As a result, the gap on the support structure becomes invisible to the viewer.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 1 illustrates at 10 an overall large area liquid crystal display system including a support structure embodying the concepts disclosed by the present invention. The large area liquid crystal display system 10 can be black and white or all natural colors and is used to provide still or video images to the public at a distance from the system. The system 10 includes a large rectangular, generally rectangular support structure 18 on which a first set of X address lines including address lines 20, 22, and 24 and an address line 2 are provided.
A second set of address lines comprising Y address lines including 6, 28 and 30, and a plurality of macroscopic size individual liquid crystal pixels (ie pixels) 32, 34, 36, 38, 40, 42, 4
4, 46 and 48 are arranged. The system 10 further includes switching elements 50, 52, 54, 56, 58, 6 operatively associated with each macroscopic size liquid crystal pixel.
Also includes 0, 62, 64 and 66.

As shown in FIG. 1, X address lines 20, 2
2 and 24 and the Y address lines 26, 28 and 30 intersect at an angle X, consisting of rows and columns which are substantially parallel.
A plurality of intersections 70, 72, 74, 76, 78, 8 because they define a Y matrix and are spaced from each other
0, 82, 84 and 86 are formed. Each X and Y
The address lines serve to send separate and independent electrical pulses supplied from an off-board electronic driver (not shown) to each macroscopic individual liquid crystal pixel. Therefore, the X address lines and the Y address lines intersect at an angle, but the X address lines 20 to 24 are the Y address lines 26 to 30.
Electrically isolated from.

Each intersection 70-86 corresponds to one of the macroscopically sized individual liquid crystal pixels 32-48. The macroscopic size discrete liquid crystal pixels 32-48 are separately mounted to the support structure 18 and evenly distributed throughout the support structure with a minimum mutual spacing. In this way, a substantially continuous large area is unobstructed, for example by the grid pattern of X and Y address lines or the spaces between the macroscopically sized discrete liquid crystal pixels 32-48 caused by the support structure 18 itself. Can provide still or video images. Although three rows and columns of pixels are shown in FIG. 1, the number of rows and columns of macroscopic size liquid crystal pixels can be arbitrarily determined in the present invention. Further, although the pixel is a square in FIG. 1, the shape of the pixel is not limited to this.
Other shapes such as rectangular or triangular may be used.

The large area display system of the present invention is designed primarily to be viewed by a large number of people, so it will naturally be located at a distance from the viewer. Therefore, even if there is a small gap between macroscopic size individual pixels, there is no problem because the ability of the human eye to recognize the size of the gap decreases as the distance from the plane of the display system increases. Actually, the result of the experiment is 10m
It was found that the 3 mm gap was not perceptible to the naked eye of a person at a distance, and this relationship was linear (ie, a 30 mm gap was not perceived at a distance of 100 m).
Further, as will be described later in detail with reference to FIG. 5, when the gap becomes too large and the quality of the image formed is adversely affected, the elongated lens means 82 (dotted line in FIG. 1) is provided. The obstructing gap can be obscured. In this way, large area video images can be provided to the public on billboards, cinema screens, marquees and large area televisions.

As already mentioned, the macroscopically sized individual liquid crystal pixels 32-48 are preferably rectangular, and more particularly square. It is important that the macroscopic size discrete liquid crystal pixel be sized and shaped such that it completely fills the compartment defined by the XY matrix matrix on the support structure 18, rather than its exact size and shape. Is. In the first preferred embodiment, the pixels are square and each side has a size of about 1 cm. In a more preferred embodiment, the pixels are square and each side is about 10 cm. In the most preferred embodiment, the macroscopically sized discrete liquid crystal pixels 32-48 are large area squares with sides of about 50 cm or more. Thus, the compartments defined between adjacent rows and columns should be able to fully accommodate the length and width dimensions of each large area pixel with a minimum gap between adjacent large area pixels. There must be.

Macroscopic size individual liquid crystal pixels 32-48
Furthermore, the depth dimension is relatively small compared to the length and width dimensions described above. In the preferred embodiment, one side of the image boundary of macroscopically sized discrete liquid crystal pixels is about 50 cm. In comparison to such lengths and widths, the depth dimension is about 5 cm or less, preferably about 1 cm or less. Such a thin, substantially flat profile has two substantially parallel profiles.
It is obtained by using a pixel containing a liquid crystal material operatively arranged between two pixel electrodes. The electrodes are deposited, for example, on opposing transparent substrates formed of a thin sheet of high quality glass. The opposing transparent glass substrate must be lightweight, but mechanically rugged to provide structural rigidity to prevent breakage and easy operation by the installer or repairer of the large area display. I won't.

Individual macroscopic size liquid crystal pixels 32-4
8 further includes switching elements 50-66 associated therewith. The switching element may be mounted or attachable to one of the transparent substrates, preferably on the side facing the deposited pixel electrode, in electrical communication with the pixel electrode. Whether or not the switching element is mechanically attached to the pixel, in the preferred embodiment, the switching elements 50-66 must be placed in electrical communication with one of the electrodes. One terminal of the switching element is preferably electrically connected to the pixel electrode located on the transparent substrate furthest to the viewer.
When the electrical contact is made in this way, the switching element is hidden from the viewer.

The switching elements 50 to 66 are constructed so as not to propagate electric pulses smaller than a predetermined threshold voltage. That is, the switching element prevents parasitic electrical pulses and electrical "noise" propagating through the XY address lines of the matrix from prematurely or inadvertently activating individual pixels associated with the switching element. To do. Switching element 50
˜66 can be individual large area devices that are manually attached to each large area pixel, such as by plug and socket connections, or can be thin film devices deposited directly on the glass substrate of each large area pixel.

In one of the preferred embodiments, the switching element includes a pair of discrete diodes 156 and 158. These diodes are arranged in an anode-to-cathode relationship to function as a switch having two diodes and three terminals (two-diode three-terminal switch). The switch is electrically connected and mechanically attached to one of the electrodes of the large area pixel. One of the main features of the dual diode switch structure is that it requires two X or row address lines per row of large area pixels. This structure will be described later in detail with reference to FIG.

In a second, more preferred embodiment, the switching element associated with each large area pixel of the XY matrix of display 10 and used to address the pixel comprises an individual transistor 120. Because this transistor is a three-terminal device, it is electrically connected to both the X and Y address lines and also to one of the electrodes of large area pixel 134.
In this way, unlike the case of the two-diode switch, it is not necessary to provide the second X address line, that is, the row address line for each pixel row. This structure will be described later in detail with reference to FIG.

FIG. 2 shows an XY on support structure 18 (FIG. 1).
The socket arrangement 100 is shown operatively associated with each intersection 70-86 and each section of the matrix. Since all socket devices 100 are substantially the same, only one socket will be described here. The socket device 100 is configured to engage a switching element associated with each large area pixel to electrically interconnect it with each pixel. As is apparent from FIG. 2, each socket device is electrically connected to the X address line 102 through the conductive lead 104, and the conductive lead 1
It is also electrically connected to the Y address line 106 via 08. For example, in the preferred embodiment where the switching element is a transistor, the first and second terminals of the transistor engage the socket 100 and are electrically connected to the X and Y address lines, respectively, and the third terminal is a large area pixel. It is arranged to be electrically connected to one of the electrodes (the other pixel electrode is grounded). To facilitate the manufacture and repair of macroscopic size displays (required when a pixel fails), each socket device 100 includes a pin connector or engages a pin connector protruding from the switching element. It is formed. In FIG. 2, this is the lead 10
And a plated through hole arranged so as to be electrically connected to the X address line 102 through
ed-through holes 110 and plated through holes 11 arranged to be electrically connected to the Y address connection 106 through the leads 108.
It was shown as 2. The plated through holes 110 and 112 are formed so as to engage with a pin connector projecting from the switching element, and this engagement makes electrical contact with the X and Y address lines and supports each large area pin. It is fixed to the body 18. Although the socket is shown here as a part of the device, the device may have pins instead of sockets.

FIG. 3 illustrates schematically how the terminals of transistor 120 are electrically connected to the first pixel electrode 132 of a single large area pixel 134 and the X and Y address lines 124 and 128 of the matrix array, respectively. As can be seen by only looking at FIG. 3, the first terminal 122 of the transistor 120 is connected to the X address line 124, the second terminal 126 of the transistor 120 is connected to the Y address line 128, and the third terminal of the transistor 120 is connected. 130 is connected to the first pixel electrode 132 of the large area pixel 134. The second pixel electrode 136 of the large area pixel 134 is connected via a lead 138 to a common potential, such as ground. Disposed between the first pixel electrode 132 and the second pixel electrode 136 of the large area display element is a layer of liquid crystal material 140 that reacts when an electric charge is applied. Applying a potential to both the X and Y address lines has the desired optical effect at the level of large area pixels. That is, the liquid crystal material changes from the non-transmissive state to the transmissive state. Addressing several such large area pixels at the same time can form a large area video or still image that can be viewed in large numbers.

Referring to FIG. 4, a pair of X or row address lines 152 and 154 and a first pixel electrode 16 of a large area pixel are connected to the anode and cathode of the two-diode switch structure of the present invention.
A method of electrically connecting to 0 is briefly shown. Figure 4
As can be seen, the row address lines 152 and 154
Includes a pair of series connected diodes 156 and 158 coupled between these address lines. A common node 157 is formed between these diodes. The common node 157 is electrically connected to the first pixel electrode 160. Large area pixel 150 also includes a second pixel electrode 162 connected to Y address line 164. First pixel electrode 160 and second pixel electrode 16
A liquid crystal material layer 166 is operatively disposed between the two. For more information on the dual diode switch structure, see Jo
US Pat. No. 4,868,616 to Hnson et al., "El
See "Electronic Matrix Array", the disclosure of which is incorporated herein by reference.

FIG. 5 is a cross-sectional view taken along line 5-5 of FIG. 1 and shows the last feature of the large area liquid crystal display of the present invention. This feature is characterized by a generally V-shaped elongated lens (also known as a butterfly lens) 82 disposed between adjacent rows and columns of macroscopically sized discrete liquid crystal pixels, eg, between pixels 34 and 36. To be done. As mentioned, this lens slightly distorts the light emitted from the edges of adjacent macroscopically sized discrete liquid crystal pixels so that the gaps formed between these pixels on the support structure are distorted. It has a function to obscure light. Of course, the amount of distortion must be extremely small so that the quality of the image formed on the large area display 10 is not adversely affected. It should be noted here that if the gap between each macroscopic size individual liquid crystal pixel can be kept sufficiently small, ie for a distance of 1 m from the viewer. If it can be maintained below 3 mm, such a lens is not necessary.

The present invention is not limited to the embodiments described above, and various modifications can be made within the scope.

[Brief description of drawings]

FIG. 1 is a front view of a large area liquid crystal display of the present invention constructed by operatively arranging a matrix array of macroscopic size pixels and switching elements on a support structure.

FIG. 2 shows a method for electrically interconnecting pixels and switching elements of a liquid crystal display according to the invention in a matrix array, in particular arranged so that the pin connectors of said pixels and switching elements can be easily inserted manually. It is explanatory drawing which shows the socket device.

FIG. 3 is an explanatory view briefly showing a method of electrically connecting a terminal of a transistor to a first pixel electrode and an X address line in a first preferred embodiment of the present invention.

FIG. 4 schematically shows a method of electrically connecting the anode and cathode of a two-diode switch to each other and also to the adjacent X address line and the first pixel electrode, respectively, in a second preferred embodiment of the present invention. FIG.

5 is a top cross-sectional view along line 5-5 of FIG. 1 showing a lens assembly of the present invention disposed in a pixel gap.

[Explanation of symbols]

18 Support structure 32, 34, 36, 38, 40, 42, 44, 46, 4
8 pixels 50, 52, 54, 56, 58, 60, 62, 64, 6
6 Switching element 82 Lens

Claims (15)

[Claims] 1. A substantially rectangular support structure suitable for viewing by a large number of people, macroscopic sized individual pixels, and non-thin film individual switching elements, said structures being substantially parallel. Defines an XY matrix of different rows and columns,
All the gaps formed between two adjacent rows and between two adjacent columns define macroscopic sized compartments, where each pixel sees the information displayed therein. A liquid crystal display material configured to present a large image area and operatively disposed between electrodes, the size of these pixels being large enough to be manually manipulated, A shape generally conforms to the shape of the compartments, one pixel is operatively arranged in each compartment of the XY matrix on the support structure, and the switching elements are rows and columns of the matrix. A large area liquid crystal display that is electrically connected to pixels to address specific pixels of the pixel at the same time. 2. A display as claimed in claim 1, in which the size of each rectangular pixel is about the same as the size of a section of the matrix of the support structure. 3. The pixel of claim 1, wherein each pixel is substantially rectangular.
Display described in. 4. The display of claim 1, wherein the pixel depth dimension is small compared to the pixel length and width dimension. 5. Each pixel has at least 1 to 50 sides.
The display of claim 3 having an image surface area of cm or greater. 6. The display of claim 1, further comprising a plurality of conductive X address lines spaced apart from each other and a plurality of conductive Y address lines spaced apart from each other. 7. The individual switching element is a transistor, each individual transistor including first, second and third terminals, the first terminal being electrically connected to an X address line and the second terminal being a Y address line. Electrically connected to the third terminal X and Y
7. A display as claimed in claim 6 electrically connected to the pixel electrodes associated with the address lines. 8. Each section on the support structure further engages first and second terminals of one of the individual transistors to electrically connect those terminals to an X address line and a Y address line, respectively. 8. A display as claimed in claim 7 which also includes means for connecting. 9. Each individual large area pixel further includes means for engaging a third terminal of one of the individual transistors to electrically connect the third terminal to one of the pixel electrodes. The display according to claim 8. 10. The display according to claim 9, wherein the second electrode of each pixel is electrically grounded. 11. The individual switching element is a diode, the diodes associated with each pixel being connected in an anode-to-cathode relationship, the cathode of the first diode being electrically connected to the first X address line. An anode of the second diode is electrically connected to an adjacent X address line, and a first pixel electrode is electrically connected to a common node between the first diode and the second diode. Item 6. A display according to item 6. 12. Means for each section on the support structure further electrically connecting the cathode of the first diode to the first X address line and the anode of the second diode to the adjacent X address line. The display of claim 11 including. 13. One of the compartments on the support structure and the switching element comprises connector pin means and the other comprises connector socket means, the socket means electrically engaging the pin means. The display according to claim 1, which is configured as follows. 14. A display as claimed in claim 13, in which the pixels and transistors are sized and shaped such that they can be electrically interconnected manually within the compartments of the support structure. 15. A support structure having grid-like voids surrounding macroscopic sized pixels, lens means being operatively disposed between the pixels to cover these voids. The display of claim 1, wherein light emitted from the periphery of the display obscures the gap through the lens.