Optics Technology最新文献

The GALAXY machine announced earlier this year is the first of its kind to bring complete automation to processes of optical astronomy. Coupled with the 40-cm Schmidt telescope and a computer at the Royal Observatory, Edinburgh, it enables astronomers to process data from the telescope in a fraction of the time it has taken in the past. It can find and measure a thousand star images in an hour. Professor Fellgett, who conceived the idea of GALAXY in 1955, describes the machine and maintains that it is likely to be exploited in many other ways, including draughting and measurement of integrated circuits.

This article surveys the more important optical work being done at A.W.R.E. This includes high-speed photography, development of cameras and laser systems and applications of holography. Some of the recent developments discussed were shown at the Physics Exhibition in March. ‘Optics at A.W.R.E.’ is the subject of an Optical Group meeting of the IPPS on 21 May, one in a series of events featuring work at various establishments.

The paper describes a method for determining the displacement component in a chosen direction on the surface of a deformed object. The method is based on hologram interferometry and uses two illumination waves. During reconstruction, two families of interference fringes are formed; the moiré fringes formed by the superposition of those two families are loci of equal displacement, measured along a direction perpendicular on the bisector of the two illumination waves. By properly choosing the illuminating directions, it is possible to form a moiré pattern corresponding to the in-plane displacements of a flat specimen. Although in the present state of the art applications of the method are confined to the laboratory, it is thought it will provide a simple tool for research in studying small deformations. Some experimental applications verifying the theory are presented.

The superiority of the mtf as a guide to the performance of an optical system over standard resolution tests is well established. The Applied Optics Research Group of the Guided Weapons Divisions is mainly concerned with the measurement of the performance of large optical systems such as telescopic sights and projection systems. In many instances such systems may not be moved, so the measurement of performance necessitates taking the measuring equipment to the system. Hence mtf measurement on a standard electronic bench is not a viable proposition. In 1967 a photographic technique, now well established, was developed at BAC. The simplicity and versatility of the equipment required for the initial measurements made this method of obtaining the mtf particularly suitable for large optical systems. This paper details the equipment required and methods used to obtain the mtf by this photographic technique and discusses the particular problems encountered.

An instrument for on-line measurement of luminous output and luminous efficiency of a vortex-stabilised argon arc lamp has been constructed. Input power to the lamp is measured with a Hall-effect multiplier and the luminous output is measured with a visually corrected selenium cell. A commercial analogue dividing unit provides a quotient signal that is proportional to the luminous efficiency of the lamp. Two ranges of 10 and 50 lumens/watt are available in the one instrument.