Patent ID: 7497122

Claim:
A method for detecting a high pressure condition within a high voltage vacuum device, comprising: providing a gas tight envelope for containing gas pressure within said high voltage vacuum device; providing a collapsible device, enclosed within said gas tight envelope, having a first surface and a second surface, said first surface fixed relative to said gas tight envelope, said second surface movable relative to said first surface with an increase in said gas pressure within said gas tight envelope; providing a shaft, having a first end and a second end, said first end attached to said second surface of said collapsible device; transmitting an optical beam to a first location on a hemispherically shaped reflecting surface; reflecting a portion of said optical beam from said first location to a second location on said hemispherically shaped reflecting surface; blocking said portion of said optical beam being reflected from said first location to said second location with a portion of said shaft, at said high pressure condition; and, providing an output responsive to blocking said portion of said optical beam.