This is a Plano-Concave Lens, type SLB-25-120NIR1, manufactured by OptoSigma. The lens has a diameter of 25.0 mm and a focal length of -120.0 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 3.3 mm and a thickness center of 2 mm. The inner and outer radii are both 0 mm, indicating a flat surface on one side and a concave surface on the other. The lens's back focal length is -121.3 mm.
This lens is coated with opt ir1 on both the front and back surfaces. This coating is specifically designed for the infrared spectrum, making it ideal for applications that use light in the 633-1064nm range. The coating enhances the lens's performance by reducing reflection and increasing transmission.
The lens is currently in stock and available for purchase. For more information, please refer to the vendor's website using the provided weblink.