Institut National D'optique

Francois Trepanier

Pierre Langlois

A device and method for recording holographic gratings by the use of a single illuminating beam, two diffraction gratings, light detectors and a slit-scanning system. The beam illuminates two slits that then define two beams that are incident on the gratings. One diffracted order from one beam and one diffracted order from the other beam then interfere on a recording plane to produce sinusoidal variations of intensity. The interfering region may instantaneously be limited by a third slit. Also, another order of diffraction from one beam may be directed toward its own light detector and so is another order of diffraction from the other beam. These two detectors allow real time monitoring of the light intensity of each beam. By moving the slits in a direction parallel to the recording plane, an area larger than the slits' width can be exposed by the interfering pattern.

Growing community of inventors

Saint-Augustin-de-Desmaures, Canada

Francois Trepanier