47-674 9 mm Dia. N-BASF64/N-BK7/N-BASF64 Steinheil Achromatic Triplet; EFL=18mm MgF2 400-700nm

The 47-674 is a high-quality achromatic triplet lens, boasting a 9 mm diameter and an effective focal length (EFL) of 18 mm. This lens is meticulously crafted from three distinct materials - N-BASF64 from Schott, N-BK7 from Schott, and again N-BASF64 from Schott. This strategic combination of materials ensures superior optical performance and minimal chromatic aberration.

The lens features a robust construction, with a thickness of 11.08 mm at the edge and 2.88 mm at the center. The inner and outer radii are thoughtfully designed to optimize light transmission and focus. The first radius (r1) is 11.25 mm, while the second (r2) and third (r3) radii are 5.89 mm and -5.89 mm respectively. The fourth radius (r4) is -11.25 mm, mirroring the first radius.

The 47-674 lens is coated with Edmund Optics' standard MgF2 coating on both the front and back surfaces, ensuring excellent transmission rates within the 400-700 nm spectral range. This coating enhances the lens's durability and resistance to environmental factors, making it an ideal choice for various applications.