Patent ID: 6087649
Filing Date: 2000-07-11
Classification: H01J,H04N

Abstract:
A night vision device comprising:an objective lens receiving light from a scene being viewed and directing this light to an image intensifier tube, said image intensifier tube providing a visible image of the scene being viewed, and an eyepiece lens providing this visible image to a user of the night vision device;said image intensifier tube including a photocathode receiving photons from the scene and releasing photoelectrons in a pattern replicating the scene, a microchannel plate having microchannels opening in the direction of said photocathode to receive the photoelectrons and responsively providing a shower of secondary emission electrons in a pattern replicating the scene, and a screen receiving the shower of secondary emission electrons and producing a visible image replicating the scene;said night vision device further including a source of electrical power at a selected voltage level, anda power supply circuit receiving said electrical power at said selected voltage level to responsively provide electrical power at plural higher voltage levels to each of: said photocathode, to opposite faces of said microchannel plate, and to said screen; said power supply circuit providing as one of said plural higher voltage levels a determined voltage level which is available for connection to said photocathode; and said power supply circuit including a switching means continually connecting and disconnecting said determined voltage level to and from said photocathode.