The 47-726 is a high-precision aspheric lens offered by Edmund Optics. This lens, with a catalog number 47-726, is made from L-BAL35 material, a product of Ohara. The lens is uncoated, which is a common choice for applications where the coating might interfere with the optical path.
The lens has a diameter of 15 mm and a numerical aperture (NA) of 0.5. The effective focal length (EFL) is 15 mm, which is also the diameter of the first principal plane (d front). The second principal plane is virtually at infinity, as indicated by the 'e front' parameter being nearly zero.
The lens's geometry is defined by several radii and thicknesses. The inner radius is zero, and the outer radius is not specified, indicating that the lens is circular and has a uniform thickness. The thickness at the edge is 2.04 mm, and the thickness at the center is 5.5 mm. The back focal length (BFL) is 11.54 mm.
The lens's shape is defined by its conic constant (k1) of -1.427973. This value indicates a moderately aspheric lens, which is designed to reduce spherical aberration and provide better image quality than a simple spherical lens.