Development of Polishing Procedure for Producing Highly Specularly Reflecting Surface for Sun Shield Panels of INSAT II TS VHRR Radiant Cooler

Abstract

VIRR Radient Cooler used for cooling of infrared detector of VHRR instrument onboard INDIAN NATIONAL SATELLITE [INSAT II] is being developed at Thermal Systems Division of ISAC/ISRO, Bangalore. This development work is being carried out with the participation of various organizations. One of the most critical requirements for maintaining the patch temperature of the cooler at crygenic low temperature purely by passive methods is the development of the highly specularly reflecting surfaces for the sun shield of the cooler. The polishing techniques and procedures for this were developed successfully. This paper presents the theoretical criteria developed, procedures evolved for polishing of sunshields of the cooler and the measurements made to evaluate the quality of polishing