What is a neutral density filter

Neutral density filter (attenuator) that is, neutral density filter, neutral density filter, neutral density attenuator, fixed neutral density film, gradient neutral density film, the use of material absorption properties of light, made of sheet, placed on the optical path, can be attenuated light intensity, this sheet element is called optical attenuator. Including fixed density filters, linear graduated density filters, circular graduated density filters and other types. Utilizing the absorption characteristics of the material to the light, made into a sheet, placed on the optical path, can be the light intensity attenuation, this sheet element is called optical attenuator light through the attenuator how much is related to the type of material, but also related to the thickness of the material. The neutral density filters are widely used in a variety of optical systems such as medical equipment light detectors, clinical biochemical analysis equipment, chemical testing equipment, and electronics imaging systems and other optical instruments.