Ultranarrow filters with good performance when tilted and cooled
Applied Optics The Optical Society 31:22 (1992) 4336-4336
Abstract:
Our latest research indicates that narrow bandpass filters of ~0.6% bandwidth (or any larger chosen width) and with good performance ar low temperature and in tilted and focused illumination can be realized by using multicavities and multimaterials.Design of narrowband filters in the infrared region
Infrared Physics Elsevier BV 31:3 (1991) 237-244
Abstract:
A method of designing multi-cavity narrowband filters is presented, which is based on a Tschebysheff optical prototype bandpass filter, the equivalent index concept and the variation of phases through the filter structure. Some design results are given.Space Exposure of Infrared Filters and Materials on the NASA Long Duration Exposure Facility (LDEF)
, 1991
Abstract:
Infrared optical-multilayer filters and materials were exposed to the space environment of low Earth for a period of nearly six years on the NASA Long Duration Exposure Facility (LDEF) mission. This report describes the effects of that environment on the physical and optical properties of filters and materials used in an experiment designed by the University of reading Infrared multilayer Laboratory. Results of the experiment comprise IR processed spectra both before (1983), and after (1990) exposure, in conjunction with unexposed control samples.Preliminary results from infrared multilayer filters and materials exposed to the space environment on the NASA LDEF mission
Infrared Technology and Applications SPIE (1990)
Abstract:
With continually increasing demands for improvements to atmospheric and planetary remote-sensing instrumentation, for both high optical system performance and extended operational lifetimes, an investigation to access the effects of prolonged exposure of the space environment to a series of infrared interference filters and optical materials was promoted on the NASA LDEF mission. The NASA Long Duration Exposure Facility (LDEF) was launched by the Space Shuttle to transport various science and technology experiments both to and from space, providing investigators with the opportunity to study the effects of the space environment on materials and systems used in space-flight applications. Preliminary results to be discussed consist of transmission measurements obtained and processed from an infrared spectrophotometer both before (1983) and after (1990) exposure compared with unexposed control specimens, together with results of detailed microscopic and general visual examinations performed on the experiment. The principle lead telluride (PbTe) and Zinc Sulphide (ZnS) based multilayer filters selected for this preliminary investigation consist of : an 8-12µm low pass edge filter, a 10.6µm 2.5% half bandwidth (HBW) double half-wave narrow bandpass filter, and a 10% HBW triple half-wave wide bandpass filter at 15µm. Optical substrates of MgF2 and KRS-5 (T1BrI) will also be discussed.System performance in IR atmospheric radiometry
Optical Thin Films and Applications SPIE (1990)