[54] RASTER SCAN DISPLAY APPARATUS FOR DYNAMICALLY VIEWING IMAGE ELEMENTS STORED IN A RANDOM ACCESS MEMORY ARRAY
[75] Inventors: Josef S. Sukonick, Cupertino; Greg J.
Tilden, San Jose, both of Calif.
[73] Assignee: Xtrak Corporation, Sunnyvale, Calif.
[21] Appl. No.: 82,592
[22] Filed: Oct 9,1979
Related U.S. Patent Documents
Reissue of:
[64] Patent No.: 4,070,710
Issued: Jan. 24,1978
Appl. No.: 650,372
Filed: Jan. 19,1976
[51] Int. CI.3 G09G1/16
[52] U.S. CI 340/724; 340/709;
340/725; 340/726; 340/731; 340/734; 340/744;
340/703; 340/793; 340/799;364/900
[58] Field of Search 340/709, 721, 725, 726,
340/731, 734, 793, 798, 799
[56] References Cited
U.S. PATENT DOCUMENTS
3,903,510 9/1975 Zobel 340/709 X
3,906,480 9/1975 Schwartz et al 340/745
3,925,776 12/1975 Swallow .
3,976,982 8/1976 Eiselen 340/705 X
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3,996,421 12/1976 Pruznick et al. .
4,011,556 3/1977 Tochitani et al 340/799 X
4,045,789 8/1977 Bristow .
OTHER PUBLICATIONS
"Raster Graphics Image Transformer"; Aeronutronic Ford Corp.; RADC-TR-75-172 Final Technical Report; Jul. 1975.
Kreitzer, Fitzgerald; "A Video Display System for
Image Processing by Computer;" IEEE Trans, on
Computers, vol. C-22, No. 2, Feb. 1973.
Product Release; Video/DMA Interface Unit; Interpre-
tation Systems Incorporated; Jun. 24, 1975.
VDI Series Video/DMA Interface Unit Device Speci-
fication Manual; Interpretation Systems Incorporated;
Sep. 1975; 54 pp.
Michael Fischer; "A Generalized Image Processor";
Computer Graphics, A Quarterly Report of Siggra-
ph-ACM; vol. 7, No. 3, Fall 1973; 9 pp.
Michael Fischer; "Raster Graphics for Spatial Applica-
tions"; Computer Graphics, A Quarterly Report of
Siggraph-ACM; vol. 9, No. 2, Summer 1975; 8 pp.
Dunn, Goyal, McCormick, Tareski; "Parametric De-
scription of a Scan-Display System"; Spring Joint
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111-117, Pergamon Press, 1977.
Primary Examiner—David L. Trafton
Attorney, Agent, or Firm—Spensley, Horn, Jubas &
Lubitz
[57] ABSTRACT
A computer graphics display system including random access raster memory for storing data to be displayed, a raster memory control unit for writing data into the raster memory, a video control unit for causing such information to be displayed on a CRT display screen, a micro control unit for controlling the function and timing of the raster memory control unit and the video control unit, and a computer adapter for facilitating
data exchange between the micro control unit and a host computer. The displayed image can have extremely high complexity with essentially no problem of display flicker. Zoom and pan features allow the use of a very complex stored image in a flexible manner, and a split-screen technique enables an operator to work on a very complex picture at a detail level while still having an overview of the total picture, or any portion thereof, simultaneously presented before him. The split-screen feature also alio -vs the simultaneous display of alphanumeric messages such as prompts, menus, or X-Y read
