49-541 6mm Dia. x -9mm FL; NIR I Coated; Double-Concave Lens 600-1050nm

The 49-541 is a double-concave lens with a diameter of 6mm and a focal length of -9mm, making it a negatively powered lens. This lens is sourced from Edmund Optics, a reputable vendor known for its high-quality optical elements. The lens is designed for use within the near-infrared (NIR) spectrum, specifically between 600-1050nm, making it suitable for a wide range of applications within this spectral range.

The lens is made from n-BK7 Schott, a popular optical glass due to its excellent optical properties and high Abbe number. This material ensures high transmittance and low dispersion, which are crucial for imaging and laser applications. The lens features a standard curve coating on both the front and back surfaces, specifically the EDM NIR-I std curve. This coating enhances the lens's performance in the NIR spectrum by reducing surface reflections and increasing transmission.

The lens's geometry includes a thickness of 1.79mm at the edge and 1mm at the center, providing a robust structure while maintaining a low profile. The inner and outer radii are both 0, indicating a simple spherical shape. The back focal length (BFL) is -9.32mm, which is slightly shorter than the effective focal length (EFL) of -9mm due to the lens's concave-concave shape.