A High-Speed, Eight-Frame Electro-Optic Camera With Multipulsed Ruby Laser Illuminator

Abstract

We have developed a high-speed, electro -optic camera that features a large format; eight frames; and an accompanying eight -pulse, ruby laser illuminator.This system offers greater resolution and versatility than has been previously available. The eight 75 -mm frames provide high dynamic spatial resolution (15 line pairs /mm) and time resolution (as short as 10 -ns exposure time) to record fine physical details of rapid events.Four independent two -frame (tube) cameras complete with objective optics comprise the eight -frame array. Finally, pulsed ruby laser illumination with spectral filtering allows photography in intense ambient light.

Feasibility analysis and demonstration of high-speed digital imaging using micro-arrays of vertical cavity surface-emitting lasers

“…The specific heat of copper is 0.385 J/g o K; therefore, for 100 g of copper submount the temperature increase is only 2.5 • C, which allows passive cooling. [7][8][9][10]…”

High-resolution imaging of hypervelocity metal jets using advanced high-speed photographic techniques

“…There were also two other attributes of using lasers: extraneous light could be excluded from the camera by the use of bandpass filtering that transmits only the wavelength of the laser light, and the technique proved very adaptable for stereo photography (Carpluk 1970;Paisley 1976). Over the past fifteen years, we have combined the best attributes of the electro-optic framing camera and pulsed laser illumination into a high speed framing photography system (Shaw 1984).…”

“…Individually triggered 75mm diameter proximity focused image converter tubes are positioned at each image plane, and have adjustable exposure times with a minimum of 12 to 15 ns. A detailed description of the camera timing and control system is provided in references Shaw 1984 andShaw 1993. The optical system consists of a 200mm to 1140mm zoom lens and a five-to-one magnifying relay lens which transmits and magnifies the image formed by the 35mm format objective optics to match the format of the 75mm image converter tubes.…”

MHz class repetitively Q-switched, high-power ruby lasers for high-speed photographic applications

“…Shaw et al is an example of a custom ruby laser system, = 694 nm, that combines the capability of using four separate regions of a ruby rod for separate Q-switched laser cavities as well as to have two of these units to form a pulse train of up to eight pulses. [2][3] Francis on the other hand, used four commercially available frequency doubled Nd:YAG lasers, = 532 nm, each with a single or double pulse output waveform. 4 The use of multiple independently triggered lasers does provide enhanced timing flexibility , i.e., to obtain pulse repetition rates in excess of 1 MHz.…”