摘要:

Fraunhofer holography is re-examined, correcting an error that has existed in the literature concerning the equation that describes the amplitude transmittance of a Fraunhofer hologram. In addition, the cases involving one and two-dimensional apertures are examined in detail, showing that a 45° phase shift exists between them. The original analysis is then extended to include a detailed description of the reconstructed image. This is accomplished by treating the hologram as a new diffracting aperture of finite extent, yielding, for the first time, a complete analytical description of the reconstructed field associated with a Fraunhofer hologram.

ISSN:0030-3909    

DOI:10.1080/713819370

出版商:Taylor & Francis Group    

年代:1976

数据来源: Taylor

摘要:

An ion-etching technique has been successfully applied to the production of blazed holographic plane gratings having various blaze angles ranging from 7 to 26 degrees. Efficiencies of the gratings thus produced were measured in the Littrow configuration as functions of an ion-etching condition, wavelength, and angle of incidence. The maximum efficiency for p -polarized light was found to be more than 64 per cent at about 3250 + for gratings etched at the beam angle of 80 degrees. Experimental results show that ion-etched gratings have the blaze property equivalent to that of holographic gratings made by means of Sheridon's method.

ISSN:0030-3909    

DOI:10.1080/713819374

出版商:Taylor & Francis Group    

年代:1976

数据来源: Taylor

摘要:

Electroplated diamond milling tools are in general use for machining toroidal surfaces on plastic lenses. Diamond-impregnated metal-bonded tools, with a variety of grit sizes and concentrations, are universally used for milling optical glass. Research with electroplated diamond tools has demonstrated that an improved finish, consistant accuracy, faster cutting, with less power consumed, can be achieved when milling crown or flint glass using a smaller number of natural diamonds than are necessary for impregnated metalbonded tools.

ISSN:0030-3909    

DOI:10.1080/713819373

出版商:Taylor & Francis Group    

年代:1976

数据来源: Taylor

摘要:

A theory of the non-linear longitudinal Kerr magneto-optic effect, previously developed for bulk materials [1], is now applied to a magnetic thin film. The material model is based on the classical equation of motion for a free electron with a finite relaxation frequency under the action of a Lorentz force. A second harmonic current density, dependent upon three non-linear conductivity tensors, reduces to results obtained by Jha [2] in the limit of vanishing ferromagnetic state. The second harmonic reflection coefficients are approximated and are given in terms of the first harmonic reflection coefficients as derived by Smith [3].

ISSN:0030-3909    

DOI:10.1080/713819368

出版商:Taylor & Francis Group    

年代:1976

数据来源: Taylor

摘要:

The problem of degrees of freedom of the images of a coherent aplanatic optical system suffering from aberrations is investigated by means of a suitable eigenfunction technique. This analysis leads to an evaluation of the number of effective degrees of freedom in the presence of band-limited noise. This number turns out to be independent of aberrations.

ISSN:0030-3909    

DOI:10.1080/713819371

出版商:Taylor & Francis Group    

年代:1976

数据来源: Taylor

摘要:

The behaviour of optical second harmonic due to crystal inhomogeneity and self-induced thermal effect has been considered for a focused laser beam. Temperature profile created due to a fundamental laser beam along the crystal length shows an increase in temperature band width for various values of focusing parameter (). Normalized second harmonic power in inhomogeneous crystals increases up to an optimum value of focusing parameter. Utility of focusing is limited due to formation of filament in crystal for higher values of focusing parameter.

ISSN:0030-3909    

DOI:10.1080/713819367

出版商:Taylor & Francis Group    

年代:1976

数据来源: Taylor

摘要:

The Japan Camera and Optical Instruments Inspection and Testing Institute (JCII) is an independent organization established to ensure the quality of Japanese cameras and optical instruments to be exported from Japan. On behalf of the Japanese Government, JCII does not allow the export of these products unless they have passed the JCII's export inspection, which is carried out in two stages: the type test and lot inspection. The former is related mainly to reliability and durability; the latter, the individual product's performance. Special mention is made of the research and development work conducted in order to improve the quality of products. Some JCII-developed instruments, such as the computer-controlled multi-purpose spectrophotometer, the JCII standard type flash meter, the OTF measuring equipment and the electronic flash units endurance tester, are mentioned in detail.

ISSN:0030-3909    

DOI:10.1080/713819369

出版商:Taylor & Francis Group    

年代:1976

数据来源: Taylor

ISSN:0030-3909    

DOI:10.1080/713819375

出版商:Taylor & Francis Group    

年代:1976

数据来源: Taylor

ISSN:0030-3909    

DOI:10.1080/713819372

出版商:Taylor & Francis Group    

年代:1976

数据来源: Taylor