Modular flat-screen television displays and modules and circuit drives therefor

• US 4,980,774 A
• Filed: 02/23/1990
• Issued: 12/25/1990
• Est. Priority Date: 07/21/1988
• Status: Expired due to Term

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Magnascreen Corporation
• Inventors: Brody, Thomas P.
• Primary Examiner(s): Chin, Tommy P.
• Application Number:
  US07/484,789
• Time in Patent Office: 305 Days
• Field of Search: 358/241, 358/230, 358/56, 358/59, 340/718, 340/719, 340/754, 340/758, 340/760, 340/781, 340/783, 340/784
• US Class Current: 348/383
• CPC Class Codes: G02F 1/13336 Combining plural substrates to produce large-area displays, e.g. tiled displays
• CPC Class Codes: G06F 3/147 using display panels
• CPC Class Codes: G09F 9/33 being semiconductor devices, e.g. diodes
• CPC Class Codes: G09G 2300/026 Video wall, i.e. juxtaposition of a plurality of screens to create a display screen of bigger dimensions
• CPC Class Codes: G09G 2360/04 Display device controller operating with a plurality of display units
• CPC Class Codes: H04N 9/12 Picture reproducers H04N9/11 takes precedence

Abstract

A modular flat-screen television display having a large area image can be made using an array of modules of easily manufacturable size and preferably removable. The image on each module extends to the edge of the module so that when placed in the array there is no substantial interruption in the television image since the distance between modules is the same as the distance between picture elements within the modules. Control and drive circuitry enable each module to be driven at the same time, thereby decreasing the time it takes to refresh the entire display. The modules contain picture elements which may be emissive, reflective or transmissive.

Claims

1. A flat-screen television display comprising:

A. a plurality of modules positioned adjacent each other to form an array the size of the desired flat-screen display;

B. each of said modules having a substrate with first and second major surfaces and edge surfaces and being capable of transmitting light, a matrix of picture elements extending over the first major surface of the substrate in a regular pattern with boundary picture elements adjacent the edge surfaces of the substrate to distances such that the regular pattern is continued substantially uninterrupted between adjacent modules, where said picture elements are formed of a thin film of a dispersion of liquid crystal droplets in a polymeric medium, a matrix of electrical switching elements extending over the first major surface of the substrate with each of said switching elements capable of activating a picture element upon receiving electrical signals through both said row and column conductive strips, row and column conductive strips each extending over the first major surface from adjacent an edge surface to adjacent an opposite edge surface of the substrate such that said each switching element can be electrically activated by a row conductive strip and a column conductive strip;

C. a light source positioned adjacent the second major surface of the substrate of at least one of said modules in the array;

D. an electrical drive circuit positioned adjacent the second major surface of each said substrate and capable of electrically activating the switching elements in correspondence to desired visual images to be formed by the picture elements over the first major surface;

E. interconnecting conductors adjacent the edge surfaces of the substrate and electrically connecting the drive circuit with the row and column conductive strips on the first major surface and electrically insulated from similar interconnecting conductors of an adjacent module; and

F. an electrical control circuit capable of categorizing incoming video signals corresponding to the modules in the array and directing the electrical signals to the drive circuit of said each module according to the portion of the television picture to be reproduced by the picture elements on that module.

2. A flat-screen television display as described in claim 1 wherein each module can be removed from the matrix and replaced by another like module.

3. A flat-screen television display as described in claim 1 wherein at least one set of row and one set of column conductive strips are provided side-by-side while retaining the corresponding distances between said picture elements of the regular pattern.

4. A flat-screen television display as described in claim 1 wherein a common light source is provided for the array of modules, and the electrical drive circuit for said each module is positioned more specifically adjacent a frame forming an extension of the edge surfaces of each said substrate.

5. A flat-screen television display as described in claim 1 wherein a light source is provided for said each module surrounded by a frame forming an extension of the edge surfaces of each said substrate, and the electrical drive circuit for said each module is positioned on a backboard positioned adjacent the light source opposite the second major surface of the substrate to enclose the light source.

6. A flat-screen television display as described in claim 1 wherein the desired video image is simultaneously and sequentially presented by the electrical control circuit to the electrical drive circuit of said each module.

7. A flat-screen television display as described in claim 1 wherein that portion of the desired video image corresponding to one module is fed sequentially to the electrical drive circuit of that module from the electrical control circuit while at the same time all the modules are being driven in parallel.

8. A flat-screen television display as described in claim 1 wherein the electrical control circuit comprises a decoder circuit and an image processor and wherein each said electrical drive circuit comprises a plurality of analog and digital switches for activating the switching elements in response to sequential signals from the image processor simultaneously fed to each said electrical drive circuit.

9. A flat-screen television display as described in claim 8 wherein the image processor further comprises:

an analog-to-digital converter, for transforming an analog video signal to a digital signal which can be easily stored;

a memory for storing one frame of the video signal in digital form;

a digital-to-analog converter for generating an analog video signal for said each module; and

a timing and control circuit for simultaneously directing different portions of the analog video signal to said each module.

10. A flat-screen television display as described in claim 9 wherein the number of said analog-to-digital converters corresponds to the number of colors in the display and there are two memories for each color.

11. A flat-screen television display as described in claim 10 wherein there is one said digital-to-analog converter for said each module.

12. A flat-screen television display as described in claim 8 wherein analog switches activate the column conductors and digital switches activate the row conductors of the switching elements.

13. A flat-screen television display as described in claim 12 wherein there are three times as many digital switches as analog switches.

14. A flat-screen television display as described in claim 12 wherein there are three times as many analog switches as digital switches.