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Lens Specifications

Design Wavelength	3500 nm	Magnification	Infinite
Numerical Aperture	0.18	Window Thickness
Clear Aperture	4.00 mm	Laser Window Material / Index	N/A
Effective Focal Length	11.0 mm	Glass	BD-2
Working Distance	9.80 mm	Surface Quality	80-50 Scratch-Dig(Entire Bulk Material)

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390021-D
C021TME-D

Vd number	-
CTE (10-6 / °C)	13.5
Thermo optic coefficient (10-6 / °C) (Δn/ΔT)	91

Surface R(mm) k A2 A4 A6 A8	Side 1 17.86 2.168822000 0.000000000 0.000000000 0.000000000 0.000000000	Side 2 - - - - - -

Side 1 and Side 2 are labeled as ASP1 and ASP2, respectively, on the drawings shown on the Specifications tab.

z	SAG as a Function of Y	A4	4th Order Aspheric Coefficient
R	Radius of Curvature	A6	6th Order Aspheric Coefficient
k	Conic Constant	A8	8th Order Aspheric Coefficient
A2	2nd Order Aspheric Coefficient	A10	10th Order Aspheric Coefficient