Field emission display, method for measuring vacuum degree thereof and method for automatically activating getter thereof

A method for measuring a vacuum degree of a field emission display, comprising the steps of:

• measuring current variations of a monitoring emitter from electron emission of a display emitter, when the vacuum degree is changed by gas molecules outgassed from a panel of the FED;
• monitoring variations of the vacuum degree in the panel of the FED according to the variations of the measured anode current;
• and
• automatically reactivating a getter based on a value associated with the current variations of the monitoring emitter.

A method for automatically activating a getter of a field emission display, comprising the steps of:

• setting up an aimed vacuum degree according to an optimal operation state of the FED;
• measuring an anode current flowing through a voltage applied to a monitoring emitter and a voltage applied to a current measuring electrode in the aimed vacuum degree, and feeding back the anode current to a heating device of the getter;
• and
• automatically operating the heating device to automatically reactivate the getter, when the fed-back anode current is reduced from a current value for the aimed vacuum degree below a predetermined range.