49-311-INK 6.25 mm Dia. N-BK7/N-SF5 Achromatic Doublet; EFL=50mm VIS-NIR 400-1000nm

The 49-311-INK is a high-quality achromatic doublet lens, sourced from the renowned optical vendor, Edmund Optics. This lens, with a diameter of 6.25 mm, is designed for use in the visible (VIS) and near-infrared (NIR) spectrum, specifically catering to the wavelength range of 400-1000nm.

The lens features a focal length (EFL) of 50mm, making it suitable for a wide range of optical applications. The achromatic design, which combines two different types of glass (N-BK7 and N-SF5), effectively reduces chromatic aberration, ensuring sharp and clear images across the entire spectral range.

The lens geometry is meticulously designed, with a central thickness of 2mm and edge thickness of 2.77mm. The radii of curvature are R1 = 30.77mm, R2 = -22.05mm, and R3 = -64.6mm, providing the lens with its unique optical properties. The lens is inked, which aids in its identification and handling.

The lens is coated with Edmund Optics' proprietary VIS-NIR coating (edm visnir0sp2002000) on both the front and back surfaces. This coating enhances the lens's transmission and reduces reflection, further improving its performance in the VIS-NIR spectrum.

The lens is classified as a multiplet, indicating that it is composed of multiple optical elements. This design allows for the precise control of optical properties, making the lens ideal for use in complex optical systems.