65-550 12.5 mm Dia. N-BASF64/N-SF66 Achromatic Doublet; EFL=12.5mm MgF2 400-700nm

The 65-550 is a high-quality achromatic doublet lens, sourced from the renowned optical vendor, Edmund Optics. This lens, with a diameter of 12.5 mm, is designed for use in the spectral range of 400-700 nm, making it suitable for a wide range of optical applications.

The lens is a multiplet, composed of two distinct elements: N-BASF64 and N-SF66. These materials, both from Schott, are known for their excellent optical properties. The first element, N-BASF64, has a refractive index of 1.5652 at 587.6 nm, while the second element, N-SF66, has a refractive index of 1.8118 at the same wavelength. This combination helps to correct chromatic aberration, a common issue in optical systems.

The lens has an effective focal length (EFL) of 12.5 mm, which is the distance from the lens's principal point to the focal point. This EFL, combined with the lens's diameter, makes it a compact and versatile option for various applications.

The 65-550 lens features a standard MgF2 coating on both the front and back surfaces. This coating, designed to minimize reflection and increase transmission, is particularly useful in applications where high transmittance is required.

The lens geometry is also noteworthy. The edge thickness is 7.29 mm, while the center thickness is 8.12 mm. The lens also features three radii of curvature: r1 is 9.53 mm, r2 is -6.92 mm, and r3 is -20.07 mm. These parameters contribute to the lens's overall performance and optical characteristics.