The 89-359 is a 25mm diameter Aspheric Lens, featuring an effective focal length (EFL) of 50mm and a numerical aperture (NA) of 0.25. This lens is sourced from Edmund Optics, a renowned vendor in the optical industry.
The lens is made of silicon, specifically identified as "silicon sal vil 1957" in the material ID. It is uncoated, which means it does not have any additional layers to enhance its optical properties. This could be beneficial in certain applications where minimal reflection is required.
The geometry of the lens is intricately designed. It has an inner radius of 0 and an outer radius of 0, indicating a symmetrical design. The thickness at the edge is 2.3mm, while the center thickness is 3mm. The back focal length (BFL) is 47.78mm.
The lens's aspheric shape is defined by its radii (r1 and r2), which are 47.913mm and 75.698mm respectively. The aspheric shape helps to reduce spherical aberration, improving the overall image quality. The lens's NA is 0.25, which is a measure of its light-gathering ability.
The lens's wavelength is 4000nm, which is in the infrared region of the spectrum. This could be useful in applications such as thermal imaging or heat sensing.