SYSTEM FOR PRODUCING A GRAY SCALE WITH A GASEOUS DISPLAY AND STORAGE PANEL USING MULTIPLE DISCHARGE ELEMENTS

• US 3,845,243 A
• Filed: 02/28/1973
• Issued: 10/29/1974
• Est. Priority Date: 02/28/1973
• Status: Expired due to Term

• Current Assignee: Techneglas LLC (Nippon Electric Glass Company Limited)
• Original Assignee: Ellsworth M. Murley, Larry J. Schmersal, Theodore C. Baker
• Inventors: Schmersal, Larry J., Baker, Theodore C., Murley, Ellsworth M.
• Primary Examiner(s): Richardson, Robert L.
• Application Number:
  US05/336,598
• Time in Patent Office: 608 Days
• Field of Search: 178/73D 340/324M 315/169R,169TV
• US Class Current: 348/797
• CPC Class Codes: H04N 3/125 using gas discharges, e.g. plasma

Abstract

A method and system for producing a gray scale in a gas discharge storage and display panel. The discharge panel is divided into a number of discharge regions each having the same number of storage and discharge areas which number is equal to the number of gray levels to be produced. In synchronism with the line by line scanning of an image a plurality of storage means are loaded for each picture element scanned with a number of information bits which corresponds to the intensity of the picture element scanned. After the scanning of each image line the stored information corresponding to that line is read out to excite the appropriate number of discharge areas in each discharge region. When viewed from a distance a gray scale is produced.

Claims

1. A system for producing a gray scale in a cross conductor gas discharge storage and display panel having discharge regions, each discharge region including a plurality of storage and discharge areas disposed laterally across said panel which correspond to the crossing areas of said conductors, comprising;

means for scanning an image field and producing an image signal corresponding thereto, means for defining a plurality of discrete gray level signal magnitudes which correspond to a plurality of discrete gray level magnitudes which said image signal exceeds, means for generating a number of information bits from the part of said image signal corresponding to each image element of said image field, the number of information bits generated for each part of said image signal corresponding to the highest gray level signal magnitude which said level detector determines that the part exceeds, means for storing the information bits for each line scanned at least for the duration of that line scan, and means for reading out the stored information bits for exciting the discharge areas of each discharge region of the panel line by line with signals corresponding to said information bits so that the number of areas in each discharge region excited corresponds to the gray level associated with the part of the image field to which that region corresponds.

2. The system of claim 1 wherein said storage means includes a plurality of sub-storage means equal in number to the number of lines of storage and discharge areas located in each discharge region, means for loading information bits corresponding to each scanned line of image signal into all of said sub-storage means;

and means for sequentially reading out said sub-storage means to sequentially excite the lines of discharge areas of each discharge region.

3. The system of claim 2 wherein each of said sub-storage means comprises a serial shift register, said level detector means has a plurality of outputs equal in number to the number of discrete gray levels and includes means for causing one or more of said outputs to go high depending on the detected gray level magnitude of said image signal, a clock means for producing said information bit signals, and gate means connected between said clock means and said serial shift registers for allowing a plurality of bit signals equal in number to the number of outputs of said level detector which are high to load said shift registers for each image element of said field.

4. The system of claim 3 wherein each serial shift register includes at least as many bit storage positions as the number of discharge areas in a row of said panel if it is excited column by column and wherein the clocks signal output of said clocks means activates a divider means for dividing said clock signal output into a number of signals equal to the number of bit positions in each shift register corresponding to one of said regions, the output of said divider means being connected to said gate means.

5. The system of claim 4 wherein said level detector means includes a plurality of Schmitt triggers.