The NENIR520B is a Neutral Density (ND) Filter, specifically designed for use in the Near-Infrared (NIR) spectrum with a center wavelength of 1550nm. This filter is manufactured by Thorlabs, a renowned vendor known for their high-quality optical components. The catalog number for this item is NENIR520B, and it can be found on the Thorlabs website, where it is currently in stock.
This filter is circular in shape, with a diameter of 12.7mm and a thickness of 1.3mm, making it suitable for a wide range of optical applications. The front and back of the filter are coated with tho nenir20b, a specialized absorptive coating that provides a high level of attenuation, specifically an Optical Density (OD) of 2.0 at the specified wavelength.
The NENIR520B features a Thin Lens shape, which is designed to minimize optical aberrations and ensure optimal performance in your optical system. The material used in this filter is UVFS MAL-1965, a proprietary material developed by Thorlabs for use in their optical filters.