LF7769-F 12.7 mm Dia. ZnSe Negative Meniscus Lens; EFL=-15mm 8-12µm

The LF7769-F is a spherical lens with a concave-convex base shape and a circular design, sourced from Thorlabs. This lens boasts a 12.7 mm diameter and a negative meniscus shape, making it suitable for a variety of optical applications. The lens has a center thickness of 2 mm and an edge thickness of 3.9 mm, providing a robust and durable structure.

The effective focal length (EFL) of this lens is -15 mm, indicating that it is a diverging lens. This is further emphasized by its back focal length (BFL) of -13.7 mm. The first radius of curvature (R1) is 13.5 mm, while the second radius of curvature (R2) is 7.5 mm, contributing to its unique optical properties.

The lens is made of ZnSe (Zinc Selenide) material, identified as "znse connolly" in the material ID. This material is known for its excellent optical properties, including high transparency in the infrared region, making it suitable for use in the 10600 nm wavelength range.

The lens is coated with AR (Anti-Reflective) coating on both the front and back surfaces, specifically the "tho znse-arced 8-12" coating. This coating is designed to reduce reflection and increase transmission in the 8-12 µm range, further enhancing the lens's performance in infrared applications.