A Television and Film Lens-Testing System

T. Wojtowicz

Lens quality is a vital factor in obtaining good television pictures. The Independent Television Companies Association (ITCA) asked the Scientific Instruments Research Association (SIRA) to design an apparatus which, while having neither the absolute precision nor the range of possibilities of a laboratory instrument, would, nonetheless, make it possible to verify the degree of conformity of lenses with the standards established by the British television services. The resulting design comprises four components: a pinhole object generator, an analyzer unit, and an electronic unit. The equipment permits measurement of the modulation transfer function (MTF) of the lens, glare, stray light, paraxial transmission and spectral transmission, relative field illuminance, and transverse chromatic aberration. The units, which are easily transportable, can be used in production centers and allow the rapid measurement of the mentioned lens characteristics. Good correlation has been achieved between this equipment and other apparatus.

Print ISSN
Published
1981-02
Content type
Original Research
DOI
10.5594/J01499