LF7185-F 12.7 mm Dia. ZnSe Negative Meniscus Lens; EFL=-40mm 8-12µm
- Type
- Lens
- Subtype
- Spherical Lens (Concave-Convex)
- Brand
- Thorlabs
Properties
- Shape
- Circular
- Diameter
- 12.7 mm
- EFL
- -40 mm
- BFL
- -33.6 mm
- R1
- 10.9 mm
- R2
- 7.6 mm
Material
- Name
- ZnSe
- Dispersion Equation
- Sellmeier
- n (λ)
- 2.402780893783937
- λ
- 10600 nm
- B1
- 4.45813734
- C1
- 0.040344681 μm2
- B2
- 0.467216334
- C2
- 0.15317139 μm2
- B3
- 2.8956629
- C3
- 2221.822369 μm2
LF7185-F 12.7 mm Dia. ZnSe Negative Meniscus Lens; EFL=-40mm 8-12µm
The LF7185-F is a spherical lens with a concave-convex base shape and a circular geometry. This lens, sourced from Thorlabs, has a diameter of 12.7 mm and a thickness of 4.3 mm at the edge, tapering down to 3 mm at the center. The effective focal length (EFL) is -40 mm, making it a negative meniscus lens. The radii of curvature for the front and back surfaces are 10.9 mm and 7.6 mm, respectively, resulting in a back focal length (BFL) of -33.6 mm.
This lens is made of ZnSe (Zinc Selenide) material, identified as "znse connolly" in the material ID. It is designed to operate at a wavelength of 10600 nm. The lens comes with anti-reflection coatings on both the front and back surfaces, specifically the THORLABS ZnSe-ARCED 8-12 coating, which is optimized for the 8-12 µm spectral range.
Please note that the inner and outer radii are both 0, indicating that this lens does not have any threading or other features on its edges. The lens is available from Thorlabs and is currently in stock, according to the vendor's website.
