The SLB-15-25NIR2 is a Plano-Concave Spherical Lens, 15.0 mm in diameter, with a focal length of -25.0 mm, sourced from OptoSigma. This lens is designed for use within the wavelength range of 750-1550nm, making it suitable for near-infrared applications.
The lens is fabricated from n-BK7 Schott, a popular optical glass due to its excellent optical properties and versatility. The Plano-Concave geometry, characterized by a flat front surface and a curved back surface with a radius of -12.98mm, results in a Back Focal Length of -26.3mm. This geometry is ideal for applications requiring light collimation or reduction of beam divergence.
The lens features a Central Thickness of 2mm and an Edge Thickness of 4.4mm, providing robustness and durability. The lens is coated with Opt IR2 on both the front and back surfaces, enhancing its performance within the specified wavelength range. This coating reduces reflection and increases transmission, thereby improving the overall efficiency of the optical system.