摘要:

Optical phase conjugation via degenerate four-wave mixing is studied in iodine solutions under pulsed laser radiation at two wavelengths (532 nm and 694 nm). The effect of using four different solvents (1,2-dibromoethane, xylene, methanol and ethanol) is studied at 532 nm. Phase conjugate reflectivities in the range of 0·1% to 0·3% are observed. The solutions exhibit a maximum reflectivity at an optimum concentration. The experimental data is analysed using the Caro-Gower model.

ISSN:0950-0340    

DOI:10.1080/713823341

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

Anisotropic aberration of a four-element acircular homogeneous planar lens is calculated on anisotropic y cut or x cut LiNbO 3 waveguide. Raytracing shows that the beam waist size increases greatly with off-axis angle. Huygens-Fresnel analysis shows a focused spot size of 2·8 μm at — 8.1 dB in the incident angle range of ± 8° indicating the number of resolvable spots to be 2100.

ISSN:0950-0340    

DOI:10.1080/713823337

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

In light scattering measurements near the gas-liquid critical point double scattering becomes a non-negligible effect. In a Rayleigh-Brillouin study onn-butane using photon correlation spectroscopy double scattering could be demonstrated. On account of the small scattering angles used the double scattering signal appeared as a short-time contribution to the autocorrelation function well separated from the single scattering Rayleigh signal which could thus be evaluated without regard to double scattering. Depolarized scattering including cross-correlation between both polarization components was also studied. Results of measurements along the critical isochore for reduced temperatures ε = (T- Tc)/Tcbetween 1.2 and 8.0 x 10-3are reported (Tcbeing the critical temperature). Whereas the results for the double scattering contribution fit well into existing theories, the origin of a depolarized single scattering Rayleigh component which was also present remains open.

ISSN:0950-0340    

DOI:10.1080/713823344

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

The problem of speckle motion and decorrelation due to displacement and/or deformation of diffusely reflecting surfaces has been investigated theoretically by many authors and various approaches have been adopted. In this paper, the relation between two approaches is discussed. It is shown that the condition of stationarity of the path differences can be derived from the cross-correlation function of speckle intensities before and after the deformation. The relationship for speckle displacements is derived. Examples of experimental verification are presented.

ISSN:0950-0340    

DOI:10.1080/713823340

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

We show in this paper thatN-coupled lasers can be treated as a special case ofNweakly coupled nonlinear oscillators. The dynamical behaviour can be described as the evolution onN-dimensional tori. We examine the simplest case of two elements and discuss some characteristics of the coupled laser system, which include the stability of the trivial solution, the stability of the inphase and out-of-phase solutions, and some symmetry considerations.

ISSN:0950-0340    

DOI:10.1080/713823356

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

Experimental and theoretical investigations on the diffraction efficiency of binary metal gratings working in total internal reflection are carried out. Using the method of amplitude transmission an expression that describes the efficiency of high diffraction orders is derived. Equations for the gratings' diffraction efficiency in the form of infinite series are obtained by the convolution method. It is demonstrated that both approaches yield one and the same result. The theoretical results are compared with the experimental data on the diffraction efficiency dependence on the angle of incidence and duty factor. Qualitatively, the theory describes satisfactorily the behaviour of the experimental relationships. A deviation is observed in the even orders and in the vicinity of the critical angle.

ISSN:0950-0340    

DOI:10.1080/713823354

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

ISSN:0950-0340    

DOI:10.1080/716099804a

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

ISSN:0950-0340    

DOI:10.1080/713823349

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

ISSN:0950-0340    

DOI:10.1080/713823339

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor