EP0214547B1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Virtual resolution displays
Assignee: International Business Machines Corp
•
Filing: 1986-08-26
•
Granted: 1993-11-10
•
Expires: 2006-08-26
Abstract
No abstract record available.
Inventors
- 👤 Satish Gupta
- 👤 Bruce David Lucas
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 12:21
CPC Classifications
G; G09; G09G; G09G5/00; G09G5/22; G09G5/24; G09G5/28; G09G1/00; G09G1/002
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
246 words
A method for improving the viewing quality of a CRT display image by apparently positioning a number of characters of the image at sub-pixel locations in the CRT display field in which the image appears, which characters are formed from a plurality of pixels and positioned at CRT pixel locations by means of command signals containing the sub-pixel address locations, each pixel having at most one intensity value assigned thereto, the sub-pixel locations being from file formats which identify pixel locations in a given display field having a higher resolution than the CRT display, the method comprising the steps of: forming a single respective low resolution representation for each character of a font which provides characters for an image in the higher resolution display field, and storing each low resolution representation in a CRT display memory; in response to a command signal, positioning the low resolution representation of a character onto the CRT display and assigning a first intensity value to each CRT pixel of said character; and if the command signal specifies a pixel address location in the high resolution display field which corresponds to a sub-pixel location in the CRT display field, changing the first intensity values of CRT pixels forming the displayed character to second intensity values, the changing of the first intensity values being made by linear interpolation using pairs of first intensity values assigned to adjacent pixels of the CRT display, whereby the characters appear to be positioned at sub-pixel locations.
Claim 2
Dependent Claim
68 words
A method as claimed in Claim 1, wherein the linear interpolation comprises at most one linear interpolation for each CRT pixel forming the number of characters, the interpolation being only with the intensity values assigned to two adjacent pixels in the same row or between one intensity value assigned to a pixel in the row and an intensity value assigned to a pixel horizontally adjacent to the row.
Claim 3
Dependent Claim
45 words
A method as claimed in Claim 1 or Claim 2 wherein the sub-pixel address locations are from printer file formats which identify pixel address locations in a printer display field of higher resolution than that of the CRT display field in which the image appears.
Claim 4
Independent Claim
41 words
A method as claimed in any preceding claim wherein a weighting function is applied to each high resolution representation of a character to obtain a single low resolution representation for each character which is then stored in a CRT display memory.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.