13-521 8 mm Dia. N-F2/N-BK7/N-F2 Hastings Achromatic Triplet; EFL=12.5mm MgF2 400-700nm

This is a Hastings Achromatic Triplet lens, catalog number 13-521, sourced from the renowned optical vendor Edmund Optics. The lens is designed with a base shape that is circular, and it boasts a diameter of 8 mm, making it a compact yet powerful optical component.

The lens's geometry is intricately designed with a range of radii and thicknesses to ensure optimal performance. The edge thickness is 5.44 mm, while the inner and outer radii are 0 mm each. The effective focal length (EFL) is 12.5 mm, and the radii (r1, r2, r3, r4) are 9.4 mm, 4.805 mm, -4.805 mm, and -9.395 mm respectively. The center thickness is 1 mm, with the 'a' and 'b' sections having thicknesses of 5.23 mm and 1 mm respectively.

The lens is composed of three materials, all from the Schott catalog. These are N-F2, N-BK7, and again N-F2. This specific combination of materials ensures high-quality achromatic performance, reducing chromatic aberration and improving overall image quality.

The lens is coated with Edmund Optics' standard MgF2 coating on both the front and back surfaces. This coating, within the 400-700nm wavelength range, enhances the lens's light transmission and durability, making it an excellent choice for various applications.