A Bonding Material Useful in the 2-14 microm Spectral Range.

A suitable bonding material for optically immersing ir detectors has been found for the 2-4-microm wavelength region, which contains several (8-14 microm, 4.4-5 microm, 2.9-4.2 microm, and 1.9 to 2.5 microm) atmospheric windows of importance for such applications as earth resources and other terrestrial mapping, optical communications from earth to satellites and other bodies, horizon sensors, and ground-based ir astronomy. This material cures to films having flexural and compressive strengths in excess of 700 kg/cm(2), high elastic moduli and heat distortion temperatures, and good visible transmittance to assist in detector and optical system alignment. Its ir transmission properties are measured and analyzed herein in combination with two substrate materials which transmit radiation well in the spectral range of interest.