System for the display of images in half tones on a matrix screen
First Claim
1. A system for the display of images in half tones on a matrix screen, comprising the following steps:
- preparing luminance information for each pixel of one of the images according to a corresponding N-bit word, N being greater than or equal to 2;
storing the luminance information in N memory planes with respect to the N-bit word;
addressing the memory planes to produce, through a sequential reading of these planes, N successive displayed images wherein any grouping of N adjacent pixels is obtained by successively extracting, for a given pixel of said grouping, one luminance bit from one of the memory planes different from those already used for said given pixel when forming the preceding images so as to extract the N bits of the luminance word corresponding to said given pixel, said addressing step extracting, in a given image of said N successive displayed images, for each of the pixels of any considered one of said groupings, one luminance bit in a different memory plane from those used for the other pixels of said considered grouping, thereby obtaining for each pixel, in the course of N successive scans of images, N-1intermediate values in addition to the luminance values black and white corresponding to binary values "0" and "1" respectively, said N-1 intermediate values corresponding to half-tones.
1 Assignment
0 Petitions
Accused Products
Abstract
The system enables the making of half-tones by using the control circuits of the matrix which are not usually designed for this purpose while producing no flicker effect. The system has a memory image with N (greater than or equal or 2) memory planes to store therein light information relating to each pixel in an N-bit word. The planes are read sequentially and thus make N-1 half-tones. In the simplest case (n=2), two planes are used and a first image is produced where any pixel is formed by a first bit, extracted from a first plane, and is preceded and followed, in rows as well as in columns, by a pixel formed by a first bit extraced from the other plane. The addressing is then determined to produce a second image by extracting, in reverse and respectively by each pixel, the second luminance bit in the other memory plane not used for the first image.
47 Citations
17 Claims
-
1. A system for the display of images in half tones on a matrix screen, comprising the following steps:
-
preparing luminance information for each pixel of one of the images according to a corresponding N-bit word, N being greater than or equal to 2; storing the luminance information in N memory planes with respect to the N-bit word; addressing the memory planes to produce, through a sequential reading of these planes, N successive displayed images wherein any grouping of N adjacent pixels is obtained by successively extracting, for a given pixel of said grouping, one luminance bit from one of the memory planes different from those already used for said given pixel when forming the preceding images so as to extract the N bits of the luminance word corresponding to said given pixel, said addressing step extracting, in a given image of said N successive displayed images, for each of the pixels of any considered one of said groupings, one luminance bit in a different memory plane from those used for the other pixels of said considered grouping, thereby obtaining for each pixel, in the course of N successive scans of images, N-1intermediate values in addition to the luminance values black and white corresponding to binary values "0" and "1" respectively, said N-1 intermediate values corresponding to half-tones. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17)
-
16. A system according to claim 3, wherein said addressing step has an image frequency corresponding to the scan period of one of said first and second images being at least equal to 90Hz for a liquid crystal matrix screen.
-
17. A system according to claim 8, wherein said addressing step has an image frequency corresponding to the scan period of one of said first and second images being at least equal to 90Hz for a liquid crystal matrix screen.
-
Specification