Fig. 1. Turning surface of optical parts with single point diamond lathe. (a) Single point diamond lathe^[32]; (b) lens being turned by single point diamond tool

Fig. 2. Precision molding process of chalcogenide glass. (a) Heating; (b) pressing; (c) annealing; (d) cooling and demoulding

Fig. 3. Surface shape and PV before and after coating. (a) Before coating (Ge); (b) after coating (Ge); (c) before coating (IG6); (d) after coating (IG6)

Fig. 4. Transmittance curves of chalcogenide glass before and after antireflection coating. (a) GASIR1^[56]; (b) 72GeSe₂18Ga₂Se₃10CsI^[57]

Fig. 5. Transmittance curves of different wavebands. (a) IG5 (1.4-2.5 μm); (b) IG5 (3.5-4.5 μm); (c) IG6 (3.7-4.8 μm)^[65]

Fig. 6. Transmittance curve of GASIR1 coated antireflection coating^[3]

Fig. 7. Transmittance curve of IG6 coated anti-reflection coating

Fig. 8. Reflectance and transmittance of iDLC films. (a) Reflectance on GASIR1^[75]; (b) transmittance on GASIR5^[76]

Fig. 9. Transmittance curve of DLC coating on chalcogenide glass substrate. (a) Method of Ref. [3]; (b) method of Ref. [67]