Results 221 to 230 of about 27,037 (263)

A Low-Loss Diffraction Grating Frequency Multiplexer

IEEE Transactions on Microwave Theory and Techniques, 1978
A quasi-optical frequency multiplexer based on a blazed diffraction grating is studied. Experimental data, supported by semi-quantitative theoretical considerations, show that the multiplexer is an efficient channel-dropping filter well suited to use in the millimeter wave region.
P.S. Henry, J.T. Ruscio
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Diffraction losses of Nd:YAG and Yb:YAG laser crystals

Optics & Laser Technology, 2001
Abstract Based on space-dependent rate equations, the lowest threshold input power for a diode end-pumped solid-state laser is obtained for the pump spot size w p →0. However, as the pump beam waist is decreased, the thermally induced effects in the laser rod would be very high.
Wenjie Xie, Young Kwon, Siu-Chung Tam, Yee-Loy Lam   +3 more
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Experimental investigation of diffraction losses in a laser resonator by means of the diffracted light

Optics Communications, 1984
Abstract In a laser resonator, a part of the diffracted light is picked-off with a knife-edge mirror. It is shown experimentally that the ratio of this picked-off light to the laser output exhibits a linear dependence on the diffraction losses which are varied by changing the mirror spacing.
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Model measurements of diffraction loss due to barriers

The Journal of the Acoustical Society of America, 1981
Propagation of tone bursts from a point source have been studied in a reverberant chamber 8.5 × 14 × 7 m. The insertion loss of a 30-cm-high barrier has been measured directly over the frequency range 1 to 10 kHz using first arrivals. Preliminary results show discrepancies with predictions from theory similar to those found by outdoor measurements ...
Jean Nicolas, T. F. W. Embleton, J. E. Piercy   +2 more
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Experimental determination of spherical resonator diffraction losses

Optics Communications, 1978
Abstract To obtain single transversal mode oscillation of a laser oscillator a pinhole has to be inserted into the resonator. This causes diffraction losses, comparable with the internal losses of the laser system. For a pulsed Nd-YAG-laser, the total losses and the diffraction losses are determined experimentally as a function of the Fresnel number ...
W. Müller, W. Rudolph, H. Weber
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Diffraction loss in the [110] direction in cubic crystals

The Journal of the Acoustical Society of America, 1990
A new ultrasonic measurement model using an angular spectrum of plane waves operating upon a Gauss–Hermite expansion of the transducer field has been used to explain the ultrasonic diffraction loss in the [110] direction in cubic crystals. In the [110] direction, the slowness surface exhibits a saddle point.
Emmanuel P. Papadakis, Frank Margetan, Byron P. Newberry   +2 more
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Polarization anisotropy of diffraction losses in a laser resonator

Soviet Journal of Quantum Electronics, 1989
A report is given of the first experimental evidence that diffraction losses depend on the polarization of light. The losses are maximal when the polarization is normal to the diffracting edge and minimal for the parallel orientation.
S A Gonchukov, A P Usov
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Diffraction losses associated with curved ultrasonic transducers

Journal of Physics D: Applied Physics, 1977
Numerical computations are used to evaluate the values of diffraction losses in a coaxial transducer pair system where the transducers are spherically curved and identically shaped. The complex pressure field of the emitting transducer on the surface of the receiver is calculated with the aid of the impulse response function of a curved radiator.
A Penttinen, M Luukkala
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To the question about the diffraction losses into the powerful orotrons

Twenty Seventh International Conference on Infrared and Millimeter Waves, 2003
The question is considered about the "dynamic" diffraction losses of electromagnetic energy from the open resonator (OR) of a powerful orotron. These losses are connected with radiation of the bunching electron beam at the effective electron-wave interaction with first space harmonic of the periodic orotron structure at excitement of the main type ...
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Diffraction losses in a laser-heated solenoid plasma

Journal of Applied Physics, 1975
A solution for diffraction loss of a laser beam propagating in a plasma light pipe is found by analogy to the tunnel effect of quantum mechanics. It is shown that diffraction tends to dissipate the beam layer by layer, working from the outside inward. A characteristic dissipation length can be defined for each layer of the beam.
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