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A general discussion of military applications of integrated optics and fiber optics is presented. Specific applications discussed are: 1) a multiterminal multiplexed data highway for aircraft and shipboard use; 2) optical fibers as tethers; 3) a 10.6-/spl mu/m heterodyne detector; and 4) integrated optical phased arrays.

The principles of infrared thermometry are reviewed. Basic properties of infrared optical materials and detectors are presented with reference to design and performance of the radiation thermometer. Application of the radiometric method to a broad class of common industrial materials forms the substance of this paper. Recent extensions of the method to temperature measurement of flames, glass and plastics are described. Applications of special interest to the Radio Engineer are included.

Two experimental models of devices for the intensification of X-ray fluorescent images were put into use in September 1950. These devices have a brightness amplification slightly over 100 times and enable detection of a 3-per cent thickness difference.

A set of equations derived to describe the optics of highly scattering materials are explained, extended, and applied to the problem of in vitro and in vivo measurement of the relative oxygen saturation of nonhemolyzed blood. Fundamental absorption and scattering coefficients are described and related to the absorption coefficient of hemolyzed blood. Diffusion equations for light photons are used to solve the scattering problem in a three-dimensional system that may be useful for in vivo oxyhemoglobin measurements. Crude application to published data from in vitro measurements on nonhemolyzed blood indicates that the scattering coefficient of whole blood is probably not very wavelength-dependent.

The results of calculations which use diffusion equations for photons to calculate optical transmission and backscattering by whole blood will be compared with a variety of published data. The purpose of this work is to demonstrate the usefulness of the diffusion theory approach to the optics of blood and to present information concerning the dependence of the scattering and absorption parameters for blood on the pertinent variables such as hemoglobin concentration, hematocrit, and optical wavelength.

Presented the electro dynamical analysis of the n-Si photonic waveguide structures. The rigorous solution of the problem was fulfilled by the Singular Integral Equations' method (SIE) using the Muller's method. Here the dispersion characteristics of six different structures with three, five and seven air holes are analyzed. The air holes are located symmetrically to the centre of the waveguide substrate in the first three structures. The air holes are shifted in the other examined structures. In the article dependencies of the phase constants and losses on the number of holes and their location with respect to the top and the bottom sides of the semiconductor substrate are presented. The dispersion characteristics' comparison of waveguides with the different location of holes inside n-Si substrate shows that especially strong dependences are observed in the behaviour of losses. Ill. 5, bibl. 9 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.111.5.344

The heterojunction Al x Ga 1-x As diode developed as an edge emitting LED is shown to be a viable light source for fiber optical communications. The optimized diodes exhibit radiance as high as 100 W/cm2-steradian, extrapolated half power CW operating lives in excess of 10,000 and are capable of 180 MHz operation for 50% light modulation.

Recent progress in the fabrication of low attentuation optical fibers raises the attractive possibility of optical communications via these waveguides. Integration of different optical functions on one substrate in the form of optical circuits will form ideal terminals for such a communication network. The authors discuss the theory, fabrication and performance of a few 'building stones' of such optical circuits. Optical directional couplers capable of coupling light from one channel to another are described and their use as switches is discussed. Distributed feedback for integrated lasers is analyzed. Laser action in a GaAs waveguide, in which distributed feedback was supplied by corrugations fabricated on the surface, is described. Longitudinal and transverse mode control of such a laser is also discussed. (Author)

The development of coherent optical sources, producing usable amounts of power, has provided a stimulus for communications research. Coherent sources in the form of lasers and parametric oscillators are available at wavelengths which span the entire optical spectrum. This paper reviews the state of the art of coherent optical sources with major emphasis on the most highly developed sources.

In the article it is considered generation of the down-conversion process, which crucially depends on the phase-matching relations between the interacting waves, in geometry of the transverse excitation of an annular periodically poled nonlinear photonic structure by a fundamental Gaussian beam. It has been investigated the probability and conditions for quasi-phase-matching (QPM) of down-conversion process in annular periodically poled media. Here it is presented in transverse geometry of light propagation, when the fundamental light beam propagates along the axis of the structure; consequently conical beams are formed as a result of the higher-order nonlinear Bragg diffraction. It has been shown strong correlation between the interacting beams polarizations and the type of the nonlinear media for realization of perfect QPM for the process. Besides, it has been calculated the two-photon amplitude of the down-conversion process in the annular nonlinear structure.© (1899) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

On last year’s I.A.F.-Congress at Amsterdam [1], I had the opportunity of pointing out that one way to produce the high radiation intensities of about 109 cal cm−2 sec−1, such as are required for photonic beam propulsion or for weapons beams, might exist in the black body radiation of heavy plasmas having some 105 centidegrees temperature.

The possibility of defects induction controlled by external electric field was experimentally demonstrated in the cholesteric liquid-crystalline films with selective reflection in visible range of light. It was verified that due to the induced defect it is possible to control the rotation of polarization plane of light propagating through liquid-crystalline structure. The investigation of three types of defects induced near the input substrate, in the centre and near the exit substrate of the film was done. The basic result of the experiment is that the maximum value of the polarization plane rotation was observed when light after propagating through ch iral liquid-crystalline photonic structure passes through the anisotropic defect layer. Keywords: Cholesteric Liquid Crystals, Chiral Photonic Crystals, Selective Reflection, Defect Structures. 1. INTRODUCTION The behaviour of polarization of light, propagating through the medium is directly connected with the optical characteristics of the medium and, therefore, provides a lot of information about medium. Apart from a merely fundamental interest, the investigation of the spatial dynamics of the light polarization state in different mediums has also great practical importance. For exampl e, application of polarization methods is used in biomedical research, industry and optoelectronics

A misunderstanding is corrected regarding the effect of phase mismatch on the gain in traveling-wave parametric amplifiers. It is shown that gains greater than unity can be obtained even when the signal and idler waves do not grow exponentially.

The measured small-signal gain of 4.8 dB/m for a sealed-off COs amplifier with average bore of 25 mm compares favorably with the highest gain published for a flowing-gas type. The saturated gain for this 9-meter amplifier was 1.2 dB/m with 95-watts output when sealed off and 1.3 dB/m with 110-watts output for a flowing-gas system.