This is a 67-422 Steinheil Achromatic Triplet lens, sourced from Edmund Optics. The lens has a diameter of 25 mm and an effective focal length (EFL) of 50 mm, making it suitable for a wide range of optical applications.
The lens is composed of three elements, specifically N-LASF45 from Schott, N-BK7 from Schott, and another N-LASF45 from Schott. This configuration ensures high-quality imaging and minimal chromatic aberration.
The lens features a standard MgF2 coating on both the front and back surfaces, optimized for the 400-700nm spectrum. This coating enhances the lens's light transmission capabilities and reduces surface reflections, further improving image quality.
The lens geometry includes a thickness edge of 20.58 mm, an inner radius of 0 mm, and an outer radius of 0 mm. The r1 and r2 radii are 31.25 mm and 18.47 mm respectively, while the r3 and r4 radii are -18.47 mm and -31.25 mm respectively. The center thickness is 6.4 mm, with additional thicknesses of 13 mm at center a and 6.4 mm at center b.
This lens is a multiplet, meaning it is a compound lens made up of multiple individual lenses. The multiplet design allows for more complex optical properties and corrections than a single lens, making it a versatile choice for many applications.