LF5961 25.4 mm Dia. CaF2 Negative Meniscus Lens; EFL=-200mm Uncoated

The LF5961 is a spherical lens with a concave-convex base shape and a circular geometry, sourced from Thorlabs. This lens has a diameter of 25.4 mm and a thickness of 5.1 mm at the edge, tapering down to 4 mm at the center. The effective focal length (EFL) of this lens is -200 mm, making it a negative meniscus lens.

The lens is made of Calcium Fluoride (CaF2) with the material ID mal-1963. It is designed to operate at a wavelength of 4000 nm. The lens's first radius of curvature (r1) is 86.2 mm, while the second radius of curvature (r2) is 41.4 mm. The back focal length (bfl) of this lens is -197.3 mm.

Notably, this lens does not have any coating, as indicated in the item data. This could affect its performance in certain applications, particularly those requiring high transmission or resistance to environmental factors. Therefore, users should consider this factor when deciding whether this lens is suitable for their needs.

The lens's web links are valid and indicate that it is in stock, making it readily available for immediate use. This lens could be an excellent choice for users looking for a high-quality, uncoated negative meniscus lens for their optical systems.