The power of laser emission is very important for Doppler velocimeters. Doppler velocimeters with high power laser allow us to investigate structure of shock and detonation waves in a nanosecond region and to perform multychannel diagnostics. Two types of single mode lasers are described in this work: High power iodine laser (= 1 .3 15 Jtm) of about 2 kW power and impulse duration of about 5-10 s; Ruby laser of 150 W power and of 200 s impulse duration. The width of spectral emission is 3. i03 cm1 for both lasers. Two interferometer systems. based on these lasers were made: FabryPerot interferometer and ORVIS. Also this paper decribes the examples of application of interferometer systems with powerful lasers. EXPERIMENTAL METHODFirst laser Doppler method was applied in Russia by Poklontsev B.A. at.al. /1/. Using Fabry-Perot interferometer and photo camera we measured instant liner velocity accelerated by electric explosion. As soon as the power of argon laser (5 W) is not sufficient for making nanosecond and subnanosecond investigations, we decided to find and to apply more powerful lasers. We changed three types of lasers: 1 . High-power Iodine laser with emission convertion to the second harmonic: 2. Ruby laser with emission mode selection: 3 . Laser on a dye-staff with single-frequency selection not featuring emission power loss.The High-power Iodine laser was made of two 60 cm long quarts pipes. The inner 24 mm pipe is filled with working substance C3F71 , the external pipe is filled with xenon and is used as the flash lamp. In free generation condition laser emits a light 5 s impulse on haff intensity level and 10 s on 0. 1 intensity level of emission. The laser emission (1.3 15 .tm) is converted by non-linear crystals DKDP and DCDA into the second mode (0.657 1m). The effectiveness of convertion was 10' , i.e. near 200 W while the width of spectral emission was 3 .iO cm' . With this laser we made a lot of experiments /2,3/. Then we began handling Ruby laser as more technological.In the Ruby laser methods of compensated phase modulation and mode selection were used for getting a single-mode generation. The wave length of laser emission is 2=O.6943 Jtm. The power of laser emission during 200 slowly goes down from 200 W to zero. After 30-50 s from the start of emission. the working condition that corresponds to 150-170 W power. The Ruby laser is easy-to-handle. so now we use three of them /4,5,6/. Today Ruby laser features the device that allows us using active negative inverse connection in slow grade switching mode to get 5 s laser impulses. to 5 kW power and width of spectral emission line of 3•lO cm' . Besides we have today the laser on a dye stuff with a special know-how. This allows us to get the power more than 1 kW while the width of spectral emission line is less than lO cm( lO cmcan be reached too). All these lasers were created to accomplish high precision measurements in physics of shock and detonation waves. We used Fabry-Perot interferometers of 30-300 mm optical base, and ORVIS. Cameras with rot...
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