ACT508-300-A 50.8 mm Dia. N-BK7/N-SF2 Unmounted Achromatic Doublet; EFL=300mm 400-700nm

The ACT508-300-A is a high-quality achromatic doublet lens, unmounted and with a diameter of 50.8 mm, sourced from the renowned optical components manufacturer, Thorlabs. This lens is designed for use within the spectral range of 400-700 nm, making it suitable for a wide array of applications within the visible light spectrum.

The lens boasts an effective focal length (EFL) of 300mm, which is a crucial factor in determining the lens's magnification and field of view. This EFL, combined with the lens's diameter, allows the ACT508-300-A to provide a high level of optical performance, particularly in systems where space is at a premium.

The lens is composed of two elements, made from N-BK7 and N-SF2 Schott glass, respectively. These materials were chosen for their excellent optical properties, including low dispersion and high transmission across the visible spectrum. The lens is coated with Thorlabs' proprietary AC400-700-A coating on both the front and back surfaces, further enhancing its performance by reducing reflection and increasing transmission.

The geometry of the lens is carefully designed to optimize its optical performance. The lens has a central thickness of 8.4mm and an edge thickness of 12.4mm, while the radii of curvature for the three surfaces are r1=153.7mm, r2=-139.9mm, and r3=-706.8mm. These parameters are crucial in determining the lens's ability to focus light, correct aberrations, and minimize distortion.