49-279-INK 40 mm Dia. N-BK7/N-SF5 Achromatic Doublet; EFL=250mm VIS 0° 425-675nm

The 49-279-INK is a high-quality achromatic doublet lens, boasting a 40 mm diameter and an effective focal length (EFL) of 250mm, specifically designed for the visible light spectrum ranging from 425 to 675nm. This lens is sourced from the renowned optical vendor, Edmund Optics, and is available for purchase on their official website.

This achromatic doublet is meticulously crafted from two types of Schott glass: N-BK7 and N-SF5. These materials are carefully selected to minimize chromatic aberration, a common issue in optical systems where different wavelengths of light are focused at different points. By combining these materials, the 49-279-INK provides clear, focused images across the entire visible light spectrum.

The lens features a sophisticated geometry, with a thickness of 10.57mm at the edge and 8mm at the center. The center thickness is further reduced to 4.5mm at the 'a' position, providing versatility in optical system design. The lens's inner and outer radii are optimized for optimal performance, although these specific values are not provided in the item data.

The 49-279-INK is coated with EDM VIS-0 standard curve coatings on both the front and back surfaces. These coatings enhance the lens's durability and performance by reducing surface reflections and improving light transmission.