355390-B 4.5 mm Dia. D-ZLAF52LA Molded Glass Aspheric Lenses; EFL=2.8 mm; NA=0.55 AR 600-1050nm

The 355390-B is a high-quality aspheric lens from Thorlabs, designed with a 4.5 mm diameter and a molded glass construction using D-ZLAF52LA material. This lens is specifically engineered for use in the 600-1050nm wavelength range, making it suitable for a wide range of optical applications.

The lens boasts an effective focal length (EFL) of 2.8 mm, which is a crucial specification for determining the lens's magnification and field of view. The lens's numerical aperture (NA) is 0.55, indicating a high light-gathering capability and a shallow depth of field. This makes the lens ideal for use in applications that require high resolution and contrast.

The lens's geometry is defined by several key parameters. The inner and outer radii are 0, suggesting a simple, circular shape. The thickness at the edge is 1.13 mm, while the center thickness is 1.9 mm. The lens's front and back surfaces have been shaped according to specific aspheric coefficients, which help to reduce spherical aberration and improve optical performance.

The lens is coated with a broadband anti-reflective coating (AR) for the 600-1050nm wavelength range, both on the front and back surfaces. This coating helps to minimize light loss due to reflection, thereby improving transmission and enhancing the overall performance of the lens.