Abstract: A method and apparatus for cleaning, detecting, and/or removing contamination from the surfaces of nominally transparent materials utilizing internal illumination of those surfaces with at least one electromagnetic radiation beam at an angle of incidence equal to or greater than the critical angle for total internal reflection. With appropriate selection of light sources and materials, the technique is effective at detecting and removing water, ice, particles, films and a variety of contaminants.

Abstract: A beam steerer/scanner (50) includes a dynamically balanced bi-index rotating element (52). The element is comprised of a pair (52A, 52B) of transparent hemispheres which are of the same size and shape, are made from two materials of equal density, but which materials have different refractive indices (n). When the element is oscillated or rotated, an incident beam (L) impinging upon the element through a coupling lens (56) is deviated from its initial path and a deviated beam (T) is emitted from the element through another coupling lens (58). Because the two materials forming the hemispheres are of equal density, the resulting assembly may be oscillated or rotated at very high speeds without causing excessive vibration or stress. The steerer/scanner provides a high (>0.95) throughput and scanning rates as high as 1 kHz are possible. A two-dimensional scanning unit can also be constructed using the same components as used to produce a one-dimensional scanner.

Abstract: A beam steerer/scanner (50) includes a dynamically balanced bi-index rotating element (52). The element is comprised of a pair (52A, 52B) of transparent hemispheres which are of the same size and shape, are made from two materials of equal density, but which materials have different refractive indices (n). When the element is oscillated or rotated, an incident beam (L) impinging upon the element through a coupling lens (56) is deviated from its initial path and a deviated beam (T) is emitted from the element through another coupling lens (58). Because the two materials forming the hemispheres are of equal density, the resulting assembly may be oscillated or rotated at very high speeds without causing excessive vibration or stress. The steerer/scanner provides a high (>0.95) throughput and scanning rates as high as 1 kHz are possible. A two-dimensional scanning unit can also be constructed using the same components as used to produce a one-dimensional scanner.

Abstract: A method and apparatus for cleaning, detecting, and/or removing contamination from the surfaces of nominally transparent materials utilizing internal illumination of those surfaces with at least one electromagnetic radiation beam at an angle of incidence equal to or greater than the critical angle for total internal reflection. With appropriate selection of light sources and materials, the technique is effective at detecting and removing water, ice, particles, films and a variety of contaminants.