Abstract:
A circuit and method for turning-on and turning-off elements of an field emission display device to protect against emitter electrode(60) and gate electrode(50) degradation. The circuit(910) includes control logic(916) having a sequencer which in one embodiment can be realized using a state machine. Upon power-on, the control logic sends an enable signal to a high voltage power supply (912) that supplies voltage to the anode electrode (914). At this time a low voltage power supply (918) and driving circuitry (920)are disabled. Upon receiving a confirmation signal from the high voltage power supply, the control logic enables the low voltage power supply which supplies voltage to the driving circuitry (920). Upon receiving a confirmation signal from the low voltage power supply (918), or optionally after expiration of a predetermined time period, the control logic (916) then enables the driving circuitry (920) which drives the gate electrodes (50) and the emitter electrodes (60) which make up the rows and columns of the FED device. Upon power down, the control logic (916) first disables the low voltage power supply (918), then the high voltage power supply (912).
Abstract:
A circuit and method for turning-on and turning-off elements of an field emission display device to protect against emitter electrode(60) and gate electrode(50) degradation. The circuit(910) includes control logic(916) having a sequencer which in one embodiment can be realized using a state machine. Upon power-on, the control logic sends an enable signal to a high voltage power supply (912) that supplies voltage to the anode electrode (914). At this time a low voltage power supply (918) and driving circuitry (920)are disabled. Upon receiving a confirmation signal from the high voltage power supply, the control logic enables the low voltage power supply which supplies voltage to the driving circuitry (920). Upon receiving a confirmation signal from the low voltage power supply (918), or optionally after expiration of a predetermined time period, the control logic (916) then enables the driving circuitry (920) which drives the gate electrodes (50) and the emitter electrodes (60) which make up the rows and columns of the FED device. Upon power down, the control logic (916) first disables the low voltage power supply (918), then the high voltage power supply (912).
Abstract:
A method of removing contaminant particles in newly fabricated filed emission displays. Contaminant particles are removed by a conditioning process which includes the steps of: a)driving an anode (20) of a field emission display (FED) to a predetermined voltage; b) slowly increasing an emission current of the FED after the anode has reached the predetermined voltage; and c) providing an ion-trapping device for catching the ions and particles knocked off, or otherwise released, by emitted electrons (40). By driving the anode to the predetermined voltage and by slowly increasing the emission current of the FED, contaminant particles are effectively removed without damaging the FED. A method of operating FEDs is also provided to prevent gate-to-emitter current during turn-on and turn-off, which comprises the steps of: a) enabling the anode display screen (20); and b) enabling the electron-emitters (40) after the anode display screen is enabled. By allowing sufficient time for the anode display screen to reach a predetermined voltage before the emitter is enabled, the emitted electrons (40) will be attracted to the anode (20).
Abstract:
Scattered or/and transmitted light is employed to determine characteristics, including dimensional information, of an object (60) such as part (10) of a flat-panel display. The dimensional information includes the average diameter of openings (62) in the object, the average density of the openings, and the average thickness of a layer (64) of the object. Light-diffraction patterns are produced to determine characteristics, such as abnormalities (146 and 148), of crossing lines (140 and 142) in such an object.
Abstract:
A method of removing contaminant particles in newly fabricated filed emission displays. Contaminant particles are removed by a conditioning process which includes the steps of: a) driving an anode (20) of a field emission display (FED) to a predetermined voltage; b) slowly increasing an emission current of the FED after the anode has reached the predetermined voltage; and c) providing an ion-trapping device for catching the ions and particles knocked off, or otherwise released, by emitted electrons (40). By driving the anode to the predetermined voltage and by slowly increasing the emission current of the FED, contaminant particles are effectively removed without damaging the FED. A method of operating FEDs is also provided to prevent gate-to-emitter current during turn-on and turn-off, which comprises the steps of: a) enabling the anode display screen (20); and b) enabling the electron-emitters (40) after the anode display screen is enabled. By allowing sufficient time for the anode display screen to reach a predetermined voltage before the emitter is enabled, the emitted electrons (40) will be attracted to the anode (20).