ISSN:0030-3909    

DOI:10.1080/713821188

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

ISSN:0030-3909    

DOI:10.1080/713821166

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

ISSN:0030-3909    

DOI:10.1080/713821176

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

ISSN:0030-3909    

DOI:10.1080/716099622

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

ISSN:0030-3909    

DOI:10.1080/716099614

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

A quantum theory of second-harmonic generation is presented in which use is made of the formal equivalence that exists between, on the one hand, the emission of a system ofNtwo-level atoms that interact via the electromagnetic field and, on the other, the generation of second harmonics. TheN-atom system is described in terms of the Dicke model, but in the so-called ‘restricted rotating-wave approximation’. An analytical, closed-form expression is found for the number of second-harmonic photons as a function of time. Also, a comparison with the semiclassical theory and with experiments is given.

ISSN:0030-3909    

DOI:10.1080/713821173

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

This paper is the first in a series on the diffraction and imaging properties of generalized curvilinear diffraction gratings. The ‘image diffraction pattern’ (IDP) of a generalized grating is defined as the optical image that is observed by the naked eye focused on the grating when it is illuminated by an arbitrarily extended diffuse source. In this paper, a general theory of the IDP is derived in both the scalar wave and geometric optics approximations. As an application of the theory, it is shown how the IDP of a generalized grating may be simulated by an optical data processing system in which the Fresnel transform of a low line density representation of the grating is filtered by an aperture of the same shape and orientation as the source. The theory is shown to lead to a simple explanation of the moiré effect first observed by Hamann and to a new technique for performing optical map transformations. As a practical test on the theory, the IDP of a circular diffraction grating is calculated and shown to be in good agreement with experiment.

ISSN:0030-3909    

DOI:10.1080/716099625a

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

This paper is the second in a series [1] of papers on the diffraction and imaging properties of generalized curvilinear diffraction gratings. In this article, a set of generalized ray equations is derived and applied to the calculation of the caustic properties of generalized gratings. No restriction is placed on the form of the ruling pattern or on the shape of the grating surface. For generalized uncrossed and off-axis plane gratings, the ruling pattern may be regarded as a contour map of some abstract surface. In this case, it is shown that the far-field caustic properties of the grating are determined by the regions of vanishing gaussian curvature on the abstract surface. As an application of the theory, a new method for laser material processing is discussed.

ISSN:0030-3909    

DOI:10.1080/716099625

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

Channelled spectra with a speckle interferometer consisting of two identical diffusers are producible for wide interferometer gaps because the order value is kept close to zero for any diffuser separation. The channelled spectrum is used to determine the dispersion of a glass plate whose refractive index is accurately determined to 3 parts in 103for wavelengths having an error of 0·13 nm. The application of the speckle interferometer as a refractometer is comparable with the method of minimum deviation in prisms since both refractometers deduce the refractivity from angle measurements.

ISSN:0030-3909    

DOI:10.1080/713821165

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

The metallic diffraction grating problem is solved forSpolarization using a conformal mapping and the surface impedance boundary condition. This completes the first differential formalism for diffraction gratings valid for good real conductors which does not require the fields inside the metal to be calculated. The method is used to calculate the electromagnetic fields diffracted by a cycloidal-groove grating. The numerical results are compared with those obtained using a rigorous formalism. It is shown that the method proposed here is particularly suited to the study of electromagnetic fields diffracted by a metallic grating, in the spectral zone corresponding to visible and infrared radiation where the conductivities of the metals generally used are high but finite.

ISSN:0030-3909    

DOI:10.1080/713821187

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor