Comparison of performances between GASIR moulded optics and existing IR optics

摘要

Umicore IR Glass has developed an industrial process to manufacture low cost chalcogenide glasses with well controlled properties. These materials called GASIR 1 and GASIR 2 are transparent in the 3-5 and 8-12 μm atmospheric windows allowing a great range of applications in thermal imaging. A high precision industrial moulding process has been developed and set up allowing to mould GASIR material directly into high quality finished spherical, aspherical and diffractive lenses. This process is especially attractive for medium and high volume applications. Specific antireflection coatings have also been developed offering a maximum transmission of 98% when coated with high efficiency coating. Several optics from 17.5 mm F/1 to 100 mm F/ 1.25 focal length based on existing germanium optics have been redesigned especially for GASIR 1 and GASIR 2 glasses. The lenses have been manufactured using Umicore's moulding technology. These chalcogenide moulded optics are used in various applications like imaging, process control, military applications and their performances (modulation transfer function has been measured) are reviewed and compared to the existing solutions made of traditional IR optics.