Photothermoplastic-based recording equipment: New features of airborne and satellite imaging

摘要

Photothermoplastic media (PTPM) is a non-silver two-layer, semiconductor-thermoplastic, structure for optical data recording which is radiative resistant. The PTPM allows to record photographic, holographic and other kinds of optical data without any wet chemical development that makes them maximal useful for remote sensing applications. Optical data of photothermoplastic recording are characterized by simplicity of developing and erasing processes. We elaborated the PTPM which is photosensitive in different spectral ranges, stable to radiation light mark, being able to record halftones and increasing the resolution of lens - PTPM system at the frequencies close to limiting characteristics of the lenses. Such a medium can work in a circular scheme providing the multiple write-erasure mode of recording. The image obtained on PTPM can be transmitted to the observation station instantly or with a necessary delay. The resolution of PTPM is a function of a thermoplastic layer thickness and varies from 200 to 1800 mm~(-1). PTPM may secure information recording in a broad spectral range from X-rays to IR. Camera is a single unit, which includes special light intensive eight-lens objective with visual resolution of 960 mm~(-1) and weight of 7 kg. Precise tape-drawing mechanism secures movement of the PTPM with the speed of 1.5 to 2.5 mm/s what is sufficient for compensation of displacement of the Earth surface. The ground tests using stroke optical focusing pattern showed resolution of 240 mm~(-1) by simultaneous movement of the apparatus and film relative to the optical focusing pattern.