Liquid crystal display having a field emission backlight

• US 20090186165A1
• Filed: 10/04/2006
• Published: 07/23/2009
• Est. Priority Date: 06/28/2006
• Status: Active Grant

• Current Assignee: InterDigital Madison Patent Holdings (InterDigital, Inc.)
• Original Assignee: Thomson Licensing (Vantiva SA)
• Inventors: Ritt, Peter Michael, Gorog, Istvan
• Granted Patent: US 9,111,742 B2
• Time in Patent Office: Days
• US Class Current: 427/532
• CPC Class Codes: G02F 1/133602 Direct backlight
• CPC Class Codes: G02F 1/133621 providing coloured light G02F1/133617, G02F1/133533 take precedence
• CPC Class Codes: G02F 1/133625 Electron stream lamps
• CPC Class Codes: H01J 63/04 Vessels provided with luminescent coatings; Selection of materials for the coatings
• CPC Class Codes: H01L 21/4814 Conductive parts

Abstract

An LCD display has a programmable backlight device that produces multiple different color fields from multiple different phosphor elements. The backlight device can be a low resolution FED device. The phosphor is applied by an electrophotographic screening process or direct electrostatic screening process. The FED device can further incorporate a wide gamut phosphor.

Claims

1. A method for manufacturing a display device comprising the steps of:

depositing a conductor on an anode plate;

aligning a mask with apertures on the anode plate such that apertures are predetermined locations over selected regions on the anode plate;

setting electric field lines between the mask and the anode plate by applying one voltage to the conductor and applying another voltage on the mask; and

forming phosphor elements on the selected regions by injecting a flux of charged phosphor particles toward the mask, the charge of the charged phosphor particles being selected such that the charged phosphor particles are forced by the electric field lines to deposit on the selected regions.

2. The method of claim 1 further comprising the steps of aligning the anode plate with a cathode plate having electron emitters associated with the phosphor elements and aligning a liquid crystal device with the anode plate such that specific elements of the liquid crystal device are aligned with specific phosphor elements on the anode plate.

3. The method of claim 1, wherein the steps of setting electric field lines and forming phosphor are repeated to deposit additional phosphor of different color.

4. The method of claim 1, wherein the phosphor particles are strontium thiogallate:

europium.

5. The method of claim I further comprising the steps of aligning the anode plate with a cathode plate having electron field emitters associated with the phosphor elements, whereby the display is a field emission display device.

6. A method for manufacturing a display device comprising the steps of

depositing an organic conductor film on an anode plate;

depositing an organic photoconductor film on an anode plate;

charging the organic photoconductor film;

discharging portions of the organic photoconductor by selectively exposing the portions to light;

applying a flux of charged phosphor of one polarity to the anode plate; and

terminating the flux when the charged phosphor fills its intended target regions.

7. The method of claim 6 further comprising the steps of aligning the anode plate with a cathode plate having electron emitters associated with the phosphor elements and aligning a liquid crystal device with the anode plate such that specific elements of the liquid crystal device are aligned with specific phosphor elements on the anode plate.

8. The method of claim 6 wherein the steps of charging, discharging, applying a flux of charged phosphor, and terminating the flux are repeated to deposit additional phosphor of different color.

9. The method of claim 6, wherein the phosphor particles are strontium thiogallate:

europium.

10. The method of claim 6 further comprising the steps of aligning the anode plate with a cathode plate having electron field emitters associated with the phosphor elements, whereby the display is a field emission display device.