共查询到20条相似文献,搜索用时 15 毫秒
1.
2.
Single-mode tuning over 500 MHz in 90 lines, and 700 MHz in 70 lines is reported for a pyrex waveguide CO2 laser in long-pulse operation. The peak power exceeds 100 W in the strongest lines, and the beam profile is diffraction limited. These features make the laser well suited as pump source for optically pumped molecular lasers.Work supported by the Danish National Science Research Council under Grant No. 11-3389 相似文献
3.
Frequency upconversion as a means of investigating the spectral characteristics of continuously tunable multiatmosphere TE CO2 lasers has been demonstrated. Phase matched mixing in proustite of 10 μm laser radiation and the output of a single-mode Nd:YAG laser has permitted Fabry-Pérot interferograms, at the 0.96 μm sum frequency, to be recorded with the aid of a conventional image converter tube. 相似文献
4.
A. V. Räisänen D. G. Crété P. L. Richards F. L. Lloyd 《International Journal of Infrared and Millimeter Waves》1986,7(12):1835-1852
Several SIS quasiparticle mixers have been designed and tested for the frequency range from 80 to 115 GHz. The sliding backshort is the only adjustable RF tuning element. The RF filter reactance is used as a fixed RF matching element. A mixer which uses a single 2×2 m2 Pb-alloy junction in a quarter-height waveguide mount has a coupled conversion gain of GM(DSB)=2.6±0.5 dB with an associated noise temperature of TM(DSB)=16.4±1.8 K at the best DSB operation point. The receiver noise temperature TR(DSB) is 27.5±0.8 K for the mixer test apparatus. This mixer provides a SSB receiver noise temperature below 50 K over the frequency range from 91 to 96 GHz, the minimum being TR(SSB)=44±4 K. Another mixer with an array of five 5×5 m2 junctions in series in a full-height wave-guide mount has much lower noise temperature TM(DSB)=6.6±1.6 K, but less gain GM(DSB)=–5.1±0.5 dB.Contribution of the U.S. Government, not subject to copyright 相似文献
5.
6.
H. Gerlach 《Optics Communications》1973,8(1):41-45
An electrooptically tunable Lyot filter was inserted into a dye laser resonator as a first stage element. The laser emission was tuned with a speed of 35 nm/μsec over a wavelength range of 20 nm. 相似文献
7.
8.
9.
10.
Pliński E.F. Witkowski J.S. Majewski B.W. Abramski K.M. 《Applied physics. B, Lasers and optics》2003,76(4):375-382
The behaviour of a rf-excited waveguide CO2 laser in the pulse regime is studied experimentally. The specific time sections of the pulse have been defined and described
in detail. The output pulse evolution versus input power, pressure of the laser mixture, output coupling, repetition frequency
and pulse width has been investigated. The spectral content of the pulse has been analysed. A model explaining the effect
of laser tuning during the pulse duration is given. The ultrahigh pulse (UHP), defined as the pulse for which the bulge effect
occurs, is predicted.
Received: 22 October 2002 / Revised version: 13 January 2003 / Published online: 26 March 2003
RID="*"
ID="*"Corresponding author. Fax: +48-71/3203-189, E-mail: eda@zr.ita.pwr.wroc.pl 相似文献
11.
R. E. Beverly III 《Optical and Quantum Electronics》1982,14(1):25-40
A six-temperature Boltzmann-equilibrium kinetics model has been developed for simulating the performance of fast-axial-flow, longitudinal-discharge CO2 lasers. The model includes the effects of electrical excitation, VV and VT collisional relaxation, thermal energy transport, distributed optical losses, and coherent radiation extraction for a CO2/N2/He/H2O mixture. Numerical predictions from the model are compared with experimental results obtained with a 2.5 kW device. 相似文献
12.
13.
《Physics letters. A》1999,264(4):251-256
We have measured the displacement thermal noise of a mechanical cantilever, made of phosphor bronze, using a laser interferometer. The measured noise spectrum agrees well with an estimation based on the fluctuation–dissipation theorem with a mechanical-admittance measurement. The frequency range where we could measure the thermal noise was from 50 to 500 Hz; this range is important for the noise characterization of interferometric gravitational wave detectors. 相似文献
14.
Air-breathing mode laser propulsion experiment with a long-pulse transversely excited (TE) CO2 laser is carried out, and its ignition problem is solved with the ignition needle of lightcraft. Owing to the ignition needle, an order of magnitude reduction in the ignition threshold is demonstrated. The result is compared with previous study. The momentum coupling coefficient is also measured in the experiment and its dependence upon laser pulse energy (6 14 J) and pulse width (20, 32, and 40 μs) is discussed. 相似文献
15.
A. J. Hughes J. O'Shaughnessy E. R. Pike A. McPherson C. Spavins T. H. Clifton 《Optical and Quantum Electronics》1972,4(4):379-384
A CO2 laser anemometer is described which gives a real-time, continuous, measure of one component of wind velocity. Results are presented of a series of trials in which the laser anemometer is compared with a conventional propeller anemometer at ranges up to 50 m from the laser. Very good agreement is observed between the outputs of the two devices. 相似文献
16.
17.
Translated from Zhurnal Prikladnoi Spekstroskopii, Vol. 51, No. 5, pp. 762–766, November, 1989. 相似文献
18.
J.F. Figueira 《Optics Communications》1974,11(3):220-224
Small signal gain measurements of a uv preionized TEA CO2 laser system are described. It is shown that the relative timing of preionization with respect to the main discharge determines the amount of electrical energy that can be deposited in the gas prior to arc formation. 相似文献
19.
Summary In this paper we present a numerical study of the SFUR (self-filtering unstable resonator) cavity resonant modes and numerical
results are compared with the experimental data. The numerical code developed for analysing the SFUR cavity will also allow
for studying a wider class of resonators, and is therefore a very useful tool in designing new laser cavities. 相似文献