Method of adjusting the colors of a polychrome plasma panel and a plasma panel using such a method

• US 5,045,846 A
• Filed: 05/08/1990
• Issued: 09/03/1991
• Est. Priority Date: 03/13/1987
• Status: Expired due to Fees

• Current Assignee: Thomson-CSF
• Original Assignee: Thomson-CSF
• Inventors: Gay, Michel, Deschamps, Jacques
• Primary Examiner(s): Brier, Jeffery A.
• Application Number:
  US07/520,467
• Time in Patent Office: 483 Days
• Field of Search: 340/702, 340/704, 340/767, 340/777, 340/772, 340/805, 315/169.1, 315/169.4
• US Class Current: 345/65
• CPC Class Codes: G09G 2320/0242 Compensation of deficiencies in the appearance of colours
• CPC Class Codes: G09G 3/2946 by introducing variations of the frequency of sustain pulses within a frame or non-proportional variations of the number of sustain pulses in each subfield
• CPC Class Codes: G09G 3/297 using opposed discharge type panels
• CPC Class Codes: H01J 11/12 with main electrodes provided on both sides of the discharge space
• CPC Class Codes: H04N 3/125 using gas discharges, e.g. plasma

Abstract

A method of adjusting the colors of a polychrome plasma panel is provided, including a plurality of elementary image points, each point being formed by several zones covered with luminophores of different colors, each of these zones corresponding to the intersection of electrodes for applying control signals and more particularly a holding signal to each zone during operation, which method consists in applying to the different zones of each elementary image point a respective holding signal at an adjustable frequency, identical for all the luminophores of the same type of all the image points of the panel, and the colors of the panel are adjusted by adjusting the frequency of the different holding signals used.

Claims

1. A glow discharge panel comprising:

means for providing a plurality of red, blue, and green color sources on said panel;

means for providing a first alternating frequency holding signal to all of said red color sources;

means for providing a second alternating frequency holding signal to all of said blue color sources;

means for providing a third alternating frequency holding signal to all of said green color sources;

means for adjusting the frequency of at least two of said alternating frequency holding signals; and

wherein each of said color sources comprises two plates, with electrodes on at least one plate, and an ionizable gas between the plates which ionizable gas emits ultra-violet radiation in response to the gas being ionized by signals, including said holding signal, being applied to said electrodes, and further comprising luminescent material on one of said plates and which emits the colored light when said emitted ultra-violet radiation is received thereon from said ionized gas;

whereby in accordance with the adjusted frequencies of said holding signals, a desired color balance of said panel is achieved.

3. A panel according to claim 1, or claim 2, wherein each of said color sources comprises a lumiphore of said color and a source of ultra-violent radiation, which ultra-violent radiation is converted into light of said color by said lumiphore.

4. A panel according to claim 1 or claim 2, wherein said color sources are substantially all of the same size, and the frequency of the red holding signal is about 68 KHz, the frequency of the green holding signal is about 36 KHz, and the frequency of the blue holding signal is about 52 KHz.

5. A panel according to claim 1 or claim 2, further comprising means for selecting the adjusting frequencies after the panel has been finished, and after experimentally determining the light characteristics of the panel.

6. A panel according to claim 1 or claim 2, wherein said color sources are arranged as part of continuous color strips.

2. A glow discharge panel comprising:

means for providing a plurality of different color sources on said panel;

means for providing separate and different alternating frequency color signals to all of said different color sources of the same color;

means for adjusting the frequency of at least one of said alternating frequency holding signals; and

wherein each of said color sources comprises two plates, with electrodes on at least one plate, and an ionizable gas between the plates which ionizable gas emits ultra-violet radiation in response to the gas being ionized by signals, including said holding signal, being applied to said electrodes, and further comprising luminescent material on one of said plates and which emits the colored light when said emitted ultra-violet radiation is received thereon from said ionized gas;

whereby in accordance with the adjusted frequency of said holding signal a desired colored balance of said panel is achieved.