Signal processing system for large screen display apparatus

• US 4,901,155 A
• Filed: 06/09/1988
• Issued: 02/13/1990
• Est. Priority Date: 07/15/1986
• Status: Expired due to Term

• Current Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Tanaka, Toshiji, Hara, Zenichiro
• Primary Examiner(s): Chin, Tommy P.
• Application Number:
  US07/204,314
• Time in Patent Office: 614 Days
• Field of Search: 358/230, 358/240, 358/241, 358/56, 358/59, 358/93, 358/60, 358/231, 340/752, 340/766, 340/783, 340/815.12, 340/815.27
• US Class Current: 348/383
• CPC Class Codes: G06F 3/1446 display composed of modules, e.g. video walls
• CPC Class Codes: G09F 9/3026 Video wall, i.e. stackable semiconductor matrix display modules video wall control systems G06F3/1446, G09G2300/026
• CPC Class Codes: G09G 2300/0452 Details of colour pixel setup, e.g. pixel composed of a red, a blue and two green components
• CPC Class Codes: G09G 2360/18 Use of a frame buffer in a display terminal, inclusive of the display panel
• CPC Class Codes: G09G 3/20 for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
• CPC Class Codes: G09G 3/2092 Details of a display terminals using a flat panel, the details relating to the control arrangement of the display terminal and to the interfaces thereto suitable for both CRT and flat panel G09G5/003; specific for a CRT G09G1/165
• CPC Class Codes: G09G 3/22 using controlled light sources
• CPC Class Codes: H04N 3/12 by switched stationary formation of lamps, photocells or light relays
• CPC Class Codes: Y10S 345/903 Modular display

Abstract

A large screen display apparatus comprising a display unit composed of a plurality of modules and a housing accommodating the display unit. Each of the modules includes a plurality of units arranged in a matrix form, a power source and a control unit. Further, each of the units includes a plurality of light emitting elements arranged in a matrix form and a drive circuit for the light emitting elements. Due to this arrangement, it is possible to provide a large screen display apparatus being economical, small in weight and volume and high in usability.

Claims

1. A display apparatus having a plurality of picture elements (2) each capable of having any one of plural display gradations, said apparatus comprising:

a display means (4) in which picture elements (2) are arranged in a matrix form of 2^a ×

2^b picture elements, where a and b are integers;

a frame memory (15) for storing c-bit data representing one of 2^c different gradations for each said picture element where c is an integer, said frame memory responding to an address input of (a+b) bits to provide a c-bit data output corresponding to a picture element identified by said (a+b)-bit address input; and

a clock signal source for providing a clock signal;

an address control section (18) for frequency-dividing said clock signal successively by factors ranging from 1/2 to (1/2)^a+b+c to obtain an output of (a+b+c) bits, wherein (a+b) of said output bits from said address control section correspond to one of said (2^a +2^b) picture elements in said display means and determine said (a+b)-bit address input to said frame memory, and wherein c of said output bits from said address control section identify a reference signal level corresponding to one of said 2^c display gradations available for each picture element;

an on-off decision section (16) for performing a comparison of the c-bit data output from said frame memory with said reference level and for producing 1-bit data output representing "on" and "off" states of said picture elements in accordance with results of said comparison; and

timing control means (FIG.

     15) for applying said 1-bit data to said picture elements and holding said 1-bit data for a predetermined period of time to drive said display means;

2. A display apparatus as claimed in claim 1 wherein said display means comprises:

groups of first control electrodes comprising control electrodes for controlling said display means connected in a vertical direction;

groups of second control electrodes comprising control electrodes for controlling said display means connected in a horizontal direction; and

at least one display element (3) comprising picture elements each arranged at an intersection of a pair of said first and second control electrodes.

3. A display apparatus as claimed in claim 2 wherein said address control section achieves one cyclical operation in the period of a field of a television signal.

4. A large screen display apparatus comprising a plurality of display modules cooperating to display a complete picture, wherein each of said modules is constructed as defined in claim 1.