Ultrafast gating of proximity-focused microchannel-plate intensifiers

Conference · Fri Jan 01 04:00:00 EST 1982

OSTI ID:5218625

Lundy, A S; Iverson, A E

Proximity-focused, microchannel-plate (MCP) image intensifiers have been used at Los Alamos for many years to allow single frame film and video exposure times in the range of 2.5 to 10 ns. There is now a program to reduce gating times to < 1 ns. This paper reviews previous work and the problems in achieving good resolution with gating times of < 1 ns. The key problems involve applying fast electrical gating signals to the tube elements. We present computer modeling studies of the combined tube, tube connection, and pulser system and show that low photocathode surface resistivity must be obtained to permit fast gating between the photocathode and the MCP input. We discuss ways of making low-resistivity S20 photocathodes, using gallium arsenide photocathodes, and various means of gating the tubes. A variety of pulser designs are being experimentally evaluated including spark gaps, avalanche transistors, Krytron tubes with sharpening gaps, step recovery diodes, and photoconductive elements (PCEs). The results of these studies are presented. Because of the high capacitances involved in most gating schemes, the tube connection geometry must be of low-impedance design, and our solution is presented. Finally, ways of testing these high-speed camera systems are discussed.

• Research Organization: Los Alamos National Lab., NM (USA)
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 5218625
• Report Number(s): LA-UR-82-1830; CONF-820822-5; ON: DE82019577
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
420800 -- Engineering-- Electronic Circuits &amp; Devices-- (-1989)
440300* -- Miscellaneous Instruments-- (-1989)
47 OTHER INSTRUMENTATION
ARSENIC COMPOUNDS
ARSENIDES
CATHODES
COMPUTERIZED SIMULATION
ELECTRODES
ELECTRON MULTIPLIERS
ELECTRON TUBES
ELECTRONIC CIRCUITS
GALLIUM ARSENIDES
GALLIUM COMPOUNDS
GATING CIRCUITS
IMAGE INTENSIFIERS
MICROCHANNEL ELECTRON MULTIPLIERS
PHOTOCATHODES
PHOTOGRAPHY
PNICTIDES
SIMULATION
ULTRAHIGH-SPEED PHOTOGRAPHY