NEUTRAL DENSITY FILTERS
Apr 2005SwissOptic AGRequest Info
SwissOptic AG offers three neutral density filters that can be produced either as analog types with a continuous gradient, or digitally, with a discrete gradient. In linear gradient filters, the optical density shifts and is defined along an axis, so the density gradient can be defined in terms of linear or logarithmic functions or as a Gaussian profile. Because the optical density of the company's circular filters changes in a circular pattern as a function of angle, the density gradient can be defined by various mathematical functions. The optical gradient of its radial filters changes from the center outward along the radius, again defining the density gradient mathematically.