Method for line field-sequential color video display

• US 5,528,262 A
• Filed: 11/02/1994
• Issued: 06/18/1996
• Est. Priority Date: 01/21/1993
• Status: Expired due to Fees

• Current Assignee: Fakespace, Incorporated
• Original Assignee: Fakespace, Incorporated
• Inventors: Bolas, Mark T., McDowall, Ian E.
• Primary Examiner(s): Kuntz, Curtis
• Assistant Examiner(s): CHIN, VIVIAN C
• Application Number:
  US08/333,621
• Time in Patent Office: 594 Days
• Field of Search: 345/88, 345/150, 345/87, 345/151, 345/94, 345/148, 348/266-270
• US Class Current: 345/664
• CPC Class Codes: G09G 2310/0235 Field-sequential colour display
• CPC Class Codes: G09G 5/02 characterised by the way in which colour is displayed details of colour display specific for CRTs G09G1/28; specific for flat matrix panels other than liquid crystal displays G09G3/2003; specific for liquid crystal displays G09G3/3607
• CPC Class Codes: H04N 9/31 Projection devices for colour picture display , e.g. using electronic spatial light modulators [ESLM]

Abstract

Describes the application of field-sequential color techniques to create a line field-sequential color display with particular advantages for head-mounted and head-coupled displays. The display is composed of a gray-scale CRT or other white display and a color shutter with fast switching time. The shutter is switched during blanking to create a color display in a sequential color fashion where the color fields are not entire frames.

Claims

1. A method for scanning a line field-sequential color video display, comprising the steps of:

(a) combining a video display having a surface emitting white light, and a color shutter, in a way that filters white light from said display into primary colors provided by said color shutter,

(b) drawing a sequence of different complete images over a time period, where each complete image in the sequence of complete images is drawn as a sequence of primary-colored lines or primary-colored groups of lines over time, such that radiation emitted from any particular physical place on the surface of the display averages out over the time period to white light having intensity within a gray scale range rather than light of a specific color,

(c) while performing step (b), sequencing said color shutter on the basis of a desired primary color for each of said primary-colored lines or said primary-colored groups of lines so as to produce said each complete image as a full-color image over time, where the full-color image can be represented as M scan lines of full-color pixels, and each of the primary-colored groups of lines consists of radiation from P of the scan lines, where P is an integer equal to much less than M/2.

2. The method of claim 1, wherein P=1.

3. The method of claim 1, wherein P=3.

4. The method of claim 1, wherein said primary colors consist of a first color, a second color, and a third color, and wherein step (b) includes the steps of:

(d) drawing a line having the first color on an elongated region on the surface of the display;

(e) after step (d), drawing a line having the second color on said elongated region; and

(f) after step (e), drawing a line having the third color on said elongated region.

5. The method of claim 4, wherein step (b) also includes the steps of:

(g) drawing a second line having the first color onto a second elongated region on the surface of the display;

(h) after step (g), drawing a second line having the second color onto said second elongated region; and

(i) after step (h), drawing a second line having the third color onto said second elongated region.

6. The method of claim 1, wherein the video display emits white light of intensity within said gray scale range.

7. A method for generating a line field-sequential display of a color image, where the color image can be represented as M scan lines of pixels, the method including the steps of:

(a) receiving video data representing P of the M scan lines, where P is an integer much less than M/2, and where the video data includes first primary color components for each of said P of the scan lines, second primary color components for said each of said P of the scan lines, and third primary color components for said each of said P of the scan lines;

(b) storing the video data in a memory;

(c) writing the first primary color components for a first one of the scan lines from the memory to a line on a display;

(d) after step (c), writing the second primary color components for the first one of the scan lines from the memory to said line on the display; and

(e) after step (d), writing the third primary color components for the first one of the scan lines from the memory to said line on the display;

(f) repeating step (c), (d), and (e), each time for a different one of said P of the scan lines, until the first primary color components, the second primary color components, and the third primary color components of all said P of the scan lines have been written on the display;

(g) repeating steps (a), (b), (c), (d), (e), and (f) to write on the display the first primary color components, the second primary color components, and the third primary color components of another subset of Q of said M scan lines, where Q is an integer much less than M/2, and Q can but need not equal P; and

(h) repeating step (g), each time for a different subset of said M scan lines, until the first primary color components, the second primary color components, and the third primary color components of all of said M scan lines have been written on the display.

8. The method of claim 7, wherein P=1.

9. The method of claim 7, wherein P=3.

10. The method of claim 7, wherein the first primary color components, the second primary color components, and the third primary color components are red, green, and blue components.

11. A system for generating a line field-sequential color video display, including:

a display emitting white light comprising a sequence of lines of pixels;

color shutter means for filtering the white light from the display to exclude, at any instant, components of the white light other than a selected one of a set of primary color components, wherein the color shutter means includes control means for sequencing the selected one of the set of primary color components on a line-by-line basis to cause the color shutter means to output a sequence of filtered lines determining a color image, wherein each of the filtered lines is a primary color component of one of the lines of pixels, and each of three consecutive ones of the filtered lines is a different primary color component of one of the lines of pixels.

12. The method of claim 11, wherein the display is a gray-scale display which emits white light comprising a sequence of lines of gray-scale pixels.