Si meniscus lenses for 3-5 um IR detectors (pyrometers)
Application: production of concrete, steel, glasses, etc.
Specification:
Material
Si
Type
meniscus lens, plano-convex lens
Diameter, mm
29 (+0/-0.2)
Central thickness, mm
4 (+/-0.2)
EFL tolerance, %
+/-2
Surface quality, scr/dig
60/40
Surface figure, fringes
N<=5, deltaN<=1 @633nm
AR coating (BBAR/BBAR type),
R @3-5 um, %<1 (see the curve below)
Fig. 1. Transmission spectra of Si meniscus lens.