Share Email Print

Proceedings Paper

Compact short-pulse laser for near-field range-gated imaging
Author(s): Fred J. Zutavern; Wesley D. Helgeson; Guillermo M. Loubriel; George J. Yates; Robert A. Gallegos; Thomas E. McDonald
Format Member Price Non-Member Price
PDF $14.40 $18.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

This paper describes a compact laser, which produces high power, wide-angle emission for a near-field, range-gated, imaging system. The optical pulses are produced by a 100 element laser diode array (LDA) which is pulsed with a GaAs, photoconductive semiconductor switch (PCSS). The LDA generates 100 ps long, gain-switched, optical pulses at 904 nm when it is driven with 3 ns, 400 A, electrical pulses from a high gain PCSS. Gain switching is facilitated with this many lasers by using a low impedance circuit to drive an array of lasers, which are connected electrically in series. The total optical energy produced per pulse is 100 microjoules corresponding to a total peak power of 100 kW. The entire laser system, including prime power (a nine volt battery), pulse charging, PCSS, and LDA, is the size of a small, hand-held flashlight, System lifetime, which is presently limited by the high gain PCSS, is an active area of research and development. Present limitations and potential improvements will be discussed. The complete range-gated imaging system is based on complementary technologies: high speed optical gating with intensified charge coupled devices (ICCD) developed at Los Alamos National Laboratory and high gain, PCSS-driven LDAs developed at Sandia National Laboratories. The system is designed for use in highly scattering media such as turbid water or extremely dense fog or smoke. The short optical pulses from the laser and high speed gating of the ICCD are synchronized to eliminate the back-scattered light from outside the depth of the field of view (FOV) which may be as short as a few centimeters. A high speed photodiode can be used to trigger the intensifier gate and set the range-gated FOV precisely on the target. The ICCD and other aspects of the imaging system are discussed in a separate paper.

Paper Details

Date Published: 28 May 1997
PDF: 8 pages
Proc. SPIE 2869, 22nd International Congress on High-Speed Photography and Photonics, (28 May 1997); doi: 10.1117/12.273439
Show Author Affiliations
Fred J. Zutavern, Sandia National Labs. (United States)
Wesley D. Helgeson, Sandia National Labs. (United States)
Guillermo M. Loubriel, Sandia National Labs. (United States)
George J. Yates, Los Alamos National Lab. (United States)
Robert A. Gallegos, Los Alamos National Lab. (United States)
Thomas E. McDonald, Los Alamos National Lab. (United States)

Published in SPIE Proceedings Vol. 2869:
22nd International Congress on High-Speed Photography and Photonics
Dennis L. Paisley; ALan M. Frank, Editor(s)

© SPIE. Terms of Use
Back to Top