Image intensifier gain uniformity improvements in sealed tubes b

Details Image intensifier gain uniformity improvements in sealed tubes b Image intensifier gain uniformity improvements in sealed tubes b

1993-09-14

1995-04-18

Sikes, William L.

Radiant energy

Photocells; circuits and apparatus

Photocell controlled circuit

250214A, 250214C, 250214LS, 250214SW, H04N 532, H01J 912

Patent

active

054080878

ABSTRACT:
The gain uniformity of sealed microchannel plate image intensifiers (MCPIs) is improved by selectively scrubbing the high gain sections with a controlled bright light source. Using the premise that ions returning to the cathode from the microchannel plate (MCP) damage the cathode and reduce its sensitivity, a HeNe laser beam light source is raster scanned across the cathode of a microchannel plate image intensifier (MCPI) tube. Cathode current is monitored and when it exceeds a preset threshold, the sweep rate is decreased 1000 times, giving 1000 times the exposure to cathode areas with sensitivity greater than the threshold. The threshold is set at the cathode current corresponding to the lowest sensitivity in the active cathode area so that sensitivity of the entire cathode is reduced to this level. This process reduces tube gain by between 10% and 30% in the high gain areas while gain reduction in low gain areas is negligible.

REFERENCES:
patent: 4178528 (1979-12-01), Kennedy
patent: 4178529 (1979-12-01), Kennedy
patent: 4541106 (1985-09-01), Belanger et al.
patent: 4638355 (1987-01-01), Melman
patent: 5314363 (1994-05-01), Murray
S. W. Thomas et al., "Microchannel Plate Intensifier Gain Uniformity Improvement in Sealed Tubes by Selective Scrubbing", prepared for the 20th International Congress on High Speed Photography and Photonics, Victoria, BC, Canada, Sep. 21-25, 1993, Lawrence Livermore National Laboratory Paper No. UCRL-JC-109349.

Affiliated with

Also associated with

Rating

Image intensifier gain uniformity improvements in sealed tubes b does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Image intensifier gain uniformity improvements in sealed tubes b, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Image intensifier gain uniformity improvements in sealed tubes b will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-68247