ISSN:0030-3909    

DOI:10.1080/713818418

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

The concept of the assessment of image quality by means of the optical transfer function (OTF) is traced from the early use of sine wave test charts through to the development of the high precision electro-optical instuments required to test modern optical systems. During the 1950's simple photoelectric equipment based on the conventional nodal slide bench, designed for visual assessment, was widely constructed. During the next decade however very poor agreement was found to exist between OTF measurements made on the same lens by different laboratories largely due to mechanical deficiencies but also because the critical dependence of image quality on spectral balance and on choice of image plane were at that time inadequately understood. The situation is even now complicated by a lack of agreement between designers on how to compute the OTF from the lens data. In spite of these difficulties an acceptable level of agreement is now being reached between laboratories for measurements near the axis and OTF has already proved its value to manufacturers and users of optical systems. It is expected that by increasing the level of international collaboration in this subject it will in this decade be possible to resolve rapidly the few remaining areas of disagreement and to work towards agreeing acceptable procedures for specifying image quality in terms of objective parameters such as OTF.

ISSN:0030-3909    

DOI:10.1080/713818412

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

The influence of the construction parameters of an optical system such as radii of curvature, refractive indices, thicknesses, and distances of lenses on the optical transfer function (O.T.F.) is discussed with the example of variation of radii. To find out the critical or uncritical parameters of a compound system, the Seidel coefficients (first aberration) are generally sufficient. Then the exact coefficients of wave aberrations are varied by given amounts and the corresponding O.T.F. is calculated and tabulated. The permissible variation of the coefficients for a given tolerance of O.T.F. in a limited spatial frequency range can be seen from the table. The presented technique is demonstrated for a lens of nine surfaces.

ISSN:0030-3909    

DOI:10.1080/713818415

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

ISSN:0030-3909    

DOI:10.1080/713818417

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

A simplified test procedure was developed that uses only the 45° target orientation. The lenses under test are focused for a given frequency on-axis. The on-axis MTF curve is recorded in one azimuth position of the lens, and the off-axis MTF curves for one selected field angle are recorded in three azimuth positions, The results obtained on ten lenses, each of two different lens types, will be presented in comparison with the results of photographic resolution tests on the same lenses. The results obtained from MTF testing appear to give better differentiation of lenses at a lower cost.

ISSN:0030-3909    

DOI:10.1080/713818416

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

In 1966 the British Calibration Service was set up to operate a nation-wide measurement scheme which includes the calibration of optical equipment. Under this scheme, industrial and other laboratories may apply for approval to issue official calibration certificates covering the measurement of optical transfer functions, and the OTF laboratory at the Royal Aircraft Establishment is being organized, in collaboration with the National Physical Laboratory, as the national standards centre to which such measurements can be referred. This work has led to a critical study of the sources of error in OTF measurement, and the main features of this study are described here.

ISSN:0030-3909    

DOI:10.1080/713818413

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

This paper describes the design and manufacture of three examples of a 50 mm focal length plano-convex lens, to a specification originated by the Assessment and Specification of Image Quality Research Group (SIRA). The features of the design pertinent to its use as a standard reference lens will be discussed and the achieved results presented.

ISSN:0030-3909    

DOI:10.1080/713818420

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

Even now many problems still exist with regard to the reliability of OTF measuring equipments which are being used in many optical companies or laboratories. In Japan, for a one year period beginning in 1967, comparison OTF tests had been carried out on ten typical Japanese equipments. In these tests the MTF's of the same sample lens under assigned conditions were measured with every equipment and the results obtained were compared with one another.

ISSN:0030-3909    

DOI:10.1080/713818419

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

ISSN:0030-3909    

DOI:10.1080/713818414

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor