The 13-500 is a high-quality aspheric lens offered by Edmund Optics, designed for use in the near-infrared (NIR) spectrum with a wavelength of 780nm. This lens is characterized by its circular base shape and uncoated surface, which is typical for applications where anti-reflective properties are not a primary concern.
The lens has an 18mm diameter and a numerical aperture (NA) of 0.6, indicating a wide acceptance angle and high light-gathering capability. The effective focal length (EFL) of this lens is 15mm, making it suitable for use in moderate magnification applications.
The geometry of the lens is defined by its inner and outer radii, both of which are 0 in this case, indicating a flat inner surface and a curved outer surface. The lens has a thickness of 2.55mm at the edge and 6.2mm at the center. The aspheric surface is defined by its conic constant (k1) of -1.002, which contributes to the lens's high optical performance.
The lens is made from S-LAH64, a high-refractive index material from Ohara, which is known for its excellent optical properties and chemical resistance. The lens is uncoated, which means it does not have any anti-reflective or protective coatings. This can be advantageous in certain applications where coatings may introduce unwanted reflections or distortions.