Patent ID: 7573642

Claim:
A collimating device for use in a system having a backlight, the collimating device comprising: an immersing layer; a reflecting layer; and an optical element layer formed from a plurality of three-dimensional, optical elements, each optical element having a light input end and a light output end, each optical element being tapered towards the backlight such that the light input end has a horizontal plane cross-sectional area that is less than that of the light output end, wherein each optical element has a vertical plane cross-section that includes at least one curved section that is an approximation of a compound parabolic concentrator and includes at least one linear section, such that uncollimated light entering the light input end of the optical element from multiple angles emerges from the light output end of the optical end as a substantially uniform sheet, and wherein the curved section is defined by an arc of a circle, and a slope of the curved section matches a slope of the at least one linear section at the intersection point of the curved section and the at least one linear section, and wherein the reflecting layer has apertures therein which correspond to the position and shape of the light input ends of the optical elements.