Circular Variable ND Filters (UV-VIS-IR) are filter wheels that linearly attenuate light as the filter is rotated. As the filter rotates, the beam intensity is customized due to the density variation of a gradient metallic coating around the filter. These filters are fully customizable in optical density gradient function, transmission gradient function, substrate type, coating materials, and size to meet customer requirements. Densities can be supplied as a standard linear or a customized gradient function. Prototype to production, ISO 9001:2015 Certified, ITAR Registered & Cybersecurity Compliant.