FND-20C02-60 20 mm Dia. Unmounted N-BK7 Visible Reflective Neutral Density Filter; t=2mm 400-700nm

The FND-20C02-60 is a high-quality Neutral Density Filter, unmounted and with a 20 mm diameter. This filter is sourced from OptoSigma, a renowned vendor in the optical industry, and is available for purchase through their official website. The filter's catalog number, FND-20C02-60, is unique to this specific product, making it easily identifiable and accessible for future reference or reordering.

This Neutral Density Filter is made from N-BK7, a type of glass manufactured by Schott AG, a leading global glass manufacturer. N-BK7 is known for its excellent optical properties, making it a popular choice for various optical applications. The filter's geometry includes a diameter of 20 mm and a thickness of 2 mm, providing a balance between durability and compactness.

The filter's coating is another notable feature. Both the front and back surfaces are coated with Opt FND-60, a reflective neutral density coating designed for the visible light spectrum (400-700 nm). This coating reduces the intensity of light passing through the filter without altering its color balance, making it ideal for applications requiring light control without color distortion.

The filter's shape is described as a Thin Lens, indicating a lens with a thickness significantly less than its diameter. This shape contributes to the filter's compactness and ease of integration into various optical systems.