The 49-549 is a high-quality double-concave lens, boasting a 20mm diameter and a focal length of -20mm. This lens is sourced from Edmund Optics, a renowned vendor known for their extensive catalog of optical elements. The lens is designed for use within the near-infrared (NIR) spectrum, specifically between 600-1050nm, making it ideal for a variety of applications within this range.
The lens is constructed from n-sf11 Schott, a high-index glass material often used in optical systems due to its excellent dispersion properties. This material helps to minimize chromatic aberration, ensuring clear and accurate image reproduction. The lens features a standard curve coating on both the front and back surfaces, specifically the 'edm nir-i std curve'. This coating is designed to enhance the lens' performance within the NIR spectrum, further optimizing its use in this range.
The geometry of the lens is carefully crafted, with an edge thickness of 5.03mm and a center thickness of 2mm. The lens' inner and outer radii are both 0, indicating a purely spherical design. The back focal length (BFL) is -20.55mm, a value that is crucial for determining the positioning of the lens within an optical system.