Ofilinvented and developed an imaging technology - Solar Blind Visible Bispectral Viewing Methods and Apparatus for locating and visualizing UV events. This unique IP technology is incorporated in Ofil imaging systems.

The bispectral systems include two sets of imaging devices: one that locates UV sources and another that gets the visible image of the scene. Both images are combined without parallax i.e., their optical axes are combined using catadioptric UV objectives and mirrors. The UV image goes directly to an image intensifier passing through a narrow band solar blind filter, while the visible light is reflected onto the camera lens.

To further enhance the light filtration, selective dichroic coatings are used on the objectives' mirrors so that only UV below 300 nm is reflected and reaches the photocathode while most of the light above this wavelength is transmitted.

To achieve perfect registration of the two images, the focal lengths of the lenses are matched. Proprietary electronic circuitry superimposes the UV image on a normal image of the object being inspected.