Camera sensors are made of silicon, sensitive to radiation from 200
nm to 1100 nm. The 400-700 nm range is the visible band while
the 700-1100 range belongs to the NIR band. The ultraviolet part of
the spectrum (200-400 nm) is generally filtered out by the camera’s
optical elements. A filter, called hot mirror, protects the sensors from
incoming NIR light. By replacing the hot mirror by a piece of glass,
the camera is enabled to capture both visible and NIR light [1].
For now, NIR and visible images of the same scene are obtained
by placing alternatively a NIR or visible blocking filter on the lens.
We are currently investigating a camera design that can simoultaneously
capture visible and NIR