UTILISATION DES VERRES POUR LA CORRECTION D'ABERRATIONS OPTIQUES CHROMATIQUES ET THERMIQUES POUR VERRES TRANSMETTANT DANS LES SPECTRES INFRAROUGE PROCHE, INTERMÉDIAIRE ET LOINTAIN

摘要

The invention relates to chalcogenide glass compositions for use in a lens system to balance thermal effects and chromatic effects and thereby provide an achromatic and athermal optical element that efficiently maintains achromatic performance across a broad temperature range. The glass composition is based on sulfur compounded with germanium, arsenic and/or gallium, and may further comprise halides of, for example, silver, zinc, or alkali metals. Alternatively, is based on selenium compounded with gallium, and preferably germanium, and contains chlorides and/or bromides of, for example, zinc, lead or alkali metals.