Optical And Semiconductor Properties Of Lead Telluride Coatings
Thin Films in Optics SPIE (1990)
Abstract:
The optical and semiconductor properties of lead telluride coatings are dependant on various factors contributing to its performance. In this paper, we will present the temperature dependant effects of single layer lead telluride coatings on the dispersion and absorption characteristics, absorption edge, and carrier concentration from 15 K to 436 K using both experimental and theoretical analysis.Investigation of ultra wideband multi-channel dichroic beamsplitters from 0.3 to 52µm
Infrared Physics Elsevier BV 30:1 (1990) 45-53
Abstract:
The development of a set of multi-channel dichroics which includes a 6 channel dichroic operating over the wavelength region from 0.3 to 52µm is described. In order to achieve the optimum performance, the optical constants of PbTe, Ge and CdTe coatings in the strongly absorptive region have been determined by use of a new iterative method using normal incidence reflectance measurement of the multilayer together with initial values of energy gap Eg and infinite refractive index n for the semiconductor model. The design and manufacture of the dichroics is discussed and the final results are presented.Performance model for cooled IR filters
Journal of Physics D: Applied Physics IOP Publishing 21:10S (1988) S71-S74
Abstract:
A low-temperature model is described for infrared multilayer filters containing PbTe (or other semiconductor) and ZnSe (or other II/VI). The model is based on dielectric dispersion with semiconductor carrier dispersion added. It predicts an improved performance on cooling such as would be useful to avoid erroneous signals from optics in spaceflight radiometers. Agreement with measurement is obtained over the initial temperature range 70-400K and wavelength range 2.5-20µm.Spectral Characterization Of Cooled Filters For Remote Sensing
Recent Developments in Infrared Components and Subsystems SPIE (1988)
Abstract:
The improvements obtained on cooling atmospheric remote-sensing instruments for space flight applications has promoted research in characterization of the necessary optical filters. By modelling the effects of temperature on the dispersive spectrum of some constituent thin film materials, the cooled performance can be simulated and compared. multilayer filter designs with the measured spectra from actual filters. Two actual filters are discussed, for the 7µm region, one a composite cut-on/cut-off design of 13% HBW and the other an integral narrowband design of 4% HBW.Design And Disposition Of Infra-Red Optical Multilayer Coatings For The Improved Stratospheric And Mesospheric Sounder (ISAMS)
Optoelectronic Technologies for Remote Sensing from Space SPIE (1988)