Browse Prior Art Database

Pixel Intensity Control on a CRT Display

IP.com Disclosure Number: IPCOM000038669D
Original Publication Date: 1987-Feb-01
Included in the Prior Art Database: 2005-Jan-31
Document File: 2 page(s) / 42K

Publishing Venue

IBM

Related People

Oh, SH: AUTHOR [+2]

Abstract

The intensity of each dot of a character display on a CRT (cathode ray tube) screen is controlled so that horizontal and vertical lines are formed to make a uniform character. In character display on a CRT screen, a horizontal line consists of consecutive dots in a row while a vertical line consists of a single dot in each row. A single dot looks less bright than consecutive dots because dots grouped together provide greater intensity. As a result, a horizontal line appears thicker than a vertical line as part of a character on a CRT screen. Accordingly, such horizontal and vertical lines appear to have unequal thicknesses and do not produce a uniform character to the viewer. Horizontal and vertical lines can be formed to produce a uniform character through controlling the intensity of each dot in the character.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 97% of the total text.

Page 1 of 2

Pixel Intensity Control on a CRT Display

The intensity of each dot of a character display on a CRT (cathode ray tube) screen is controlled so that horizontal and vertical lines are formed to make a uniform character. In character display on a CRT screen, a horizontal line consists of consecutive dots in a row while a vertical line consists of a single dot in each row. A single dot looks less bright than consecutive dots because dots grouped together provide greater intensity. As a result, a horizontal line appears thicker than a vertical line as part of a character on a CRT screen. Accordingly, such horizontal and vertical lines appear to have unequal thicknesses and do not produce a uniform character to the viewer. Horizontal and vertical lines can be formed to produce a uniform character through controlling the intensity of each dot in the character. This is accomplished by using a programmed intensity control font. A video controller 1 controls a character generator font 2 and an intensity control font 3 so that dots displayed on a CRT screen are intensified when they represent a vertical line of a character. This increased intensity of the dots of the vertical line makes a vertical line appear to be the same thickness as a horizontal line. This may be done in a standard system, as shown, in which data is from a personal computer and in which attributes, such as highlighting, are combined with serial character data in control logic.

1

Page 2 of 2

2

[This page...