Abstract: Ultraviolet light processors are provided with means for moving concave cylindrical reflectors toward and away from generally linear sources of ultraviolet light associated with the reflectors to change the distribution of intensity of ultraviolet light impinging upon a workpiece.

Abstract: A substrate coated with an ultraviolet light curable coating composition is passed under the substantially elliptical cylindrical reflectors of an ultraviolet light coatings processor wherein sources of ultraviolet light are located at the foci nearest the vertices of the reflectors. It has been found that undercuring resulting from vibration of the coated substrate toward and away from the reflectors during passage can be eliminated by maintaining the mean point of vibration more remote from the reflectors than the conjugate foci of the reflectors.

Abstract: A substrate coated with an ultraviolet light curable coating composition is passed under the substantially elliptical cylindrical reflectors of an ultraviolet light coatings processor wherein sources of ultraviolet light are located at the foci nearest the vertices of the reflectors. It has been found that undercuring resulting from vibration of the coated substrate toward and away from the reflectors during passage can be eliminated by maintaining the mean point of vibration more remote from the reflectors than the conjugate foci of the reflectors.

Abstract: Ultraviolet light processors are provided with rotating cylindrical shutters which, depending upon their position, hinder or permit impingement of ultraviolet light upon a workpiece. The rotary configuration allows for compactness in construction of the processor.

Abstract: Air cooling means useful in conjunction with UV processors, i.e. apparatus for treating products with ultraviolet light, is adapted to impinge relatively high velocity cooling air onto the product being treated while minimizing contact of the cooling air with the lamp providing the ultraviolet light. The air cooling means comprises oppositely spaced slot-like nozzles and an exhaust channel to remove the air without contacting the ultraviolet lamp. In preferred embodiments, the nozzles direct the air angularly away from the ultraviolet lamp and toward a longitudinal exhaust channel positioned between and above the nozzles. It is preferred that the UV processor have a plurality of ultraviolet lamps with air cooling means adjacent to and following each such lamp.