This is a Plano-Concave Lens, type SLB-15-40NM, offered by OptoSigma. The lens has a diameter of 15.0 mm and a focal length of -40.0 mm, making it a negatively powered lens. The lens is made of n-bk7 schott material, a popular choice for its high refractive index and low dispersion.
The lens's geometry includes a thickness edge of 3.4 mm and a thickness center of 2 mm. The inner radius is 0 mm, and the outer radius is also 0 mm, indicating a flat surface on both sides. The lens's front and back are coated with opt m, a coating that enhances the lens's performance in the 400-700nm wavelength range.
The lens is designed for use in the visible light spectrum, with a central wavelength of 546.1 nm. It is spherical in shape, a common geometry for optical lenses due to its ease of manufacturing and high optical quality.
The lens is currently in stock and can be purchased directly from the OptoSigma website using the provided weblink. This lens is suitable for various applications, including imaging systems, beam shaping, and optical testing.