Linear Variable Filter/Gradient Filter

A linear variable filter, also known as a continuously variable filter, changes spectral properties along one dimension. For each physical point along one axis, the filter spectral curve is shifted in the wavelength domain. The change is oftentimes quasi-linear, hence the common name of linear variable filters.

A linear variable filter is manufactured by depositing many thin film layers with varying thicknesses. The thickness change results in a change in filter spectral response.

Typical continuous variable filters include short and long pass. Solaris Optics manufactures bespoke linear variable filters with custom size and spectral response. One of them is the gradient filter which is a part of the Sentinel-5 space project.

Should you be interested to learn more about our capabilities for continuous variable filters, please do not hesitate to get in touch!