Integrated beam shaper and use thereof

Abstract

A substrate having an optical element on an input surface thereof receives a light beam not having a desired beam shape and shapes the light beam into a predetermined intensity distribution. The substrate may further include a second optical element for providing a predetermined phase pattern to the light beam provided by the first optical element. The first optical element may, for example, circularize an elliptical light beam using a soft aperture for differential power attenuation or by altering the divergence of the light beam along the different axes of the light beam. When the divergence angles are altered and the collimating optical element is provided on the output surface, the thickness of the transparent substrate is determined in accordance with a resultant difference in the divergence and/or with the initial difference in beam size along each axis and with a required circularity. A light source is mounted close to the first optical element in order to minimize the amount of differing divergence present along the different axes of the light beam. The optical elements may be diffractive, refractive, or hybrids thereof and are preferably prepared photolithographically on the substrate itself. The light source may be mounted using fiducial marks and the photolithographic processes for forming the optical elements may also use fiducial marks. All elements of the integrated beam shaper may be formed on a planar, wafer level.