LE1156-C 25.4 mm Dia. N-BK7 Positive Meniscus Lens; EFL=125mm 1050-1700nm

The LE1156-C is a 25.4 mm diameter Spherical Lens with a Positive Meniscus shape, sourced from the reputable optical components manufacturer, Thorlabs. This lens is specifically designed for use within the wavelength range of 1050-1700nm, making it suitable for a variety of applications within the near-infrared spectrum.

The lens features an effective focal length (EFL) of 125mm, which is a critical specification for determining the lens's magnification power and field of view. The EFL, combined with the lens's geometry, contributes to the lens's ability to focus light, making it an essential component in many optical systems.

The LE1156-C's geometry includes a 2mm thickness at the edge and a 3.3mm thickness at the center. The lens's front and back radii are 40.6mm and 106.9mm, respectively, and the back focal length (BFL) is 121.2mm. The lens is made from N-BK7 Schott glass, a popular choice for its high refractive index and low dispersion, making it ideal for a wide range of optical applications.

The lens is coated with Thorlabs' proprietary coating, denoted as "tho c bbar". This coating is applied to both the front and back surfaces of the lens, enhancing its transmission capabilities within the specified wavelength range.