Light guide based optical system for laser line generator

摘要

A laser line generator system that utilizes a light guide element to convert high energy coherent light generated by a high fill-factor laser diode bar into homogenous light, and utilizes one or more slow-axis relay lenses to image the homogenous light such that it forms a homogenous line illumination pattern on an illumination plane. The light guide utilizes parallel or down-tapered side walls to mix received coherent light in the slow-axis direction by way of total internal reflection. A Keplerian telescope including two cylinder lenses is optionally used in place of the slow-axis relay lens. Optional fast-axis lenses are used to assist in focusing the homogenous light at the illumination plane. The laser light generator forms, e.g., a single-pass imaging system for a scanning/printing apparatus in which the homogenous line illumination pattern is directed onto a linearly arranged series of spatial light modulators, such as Digital Micromirror Devices (DMDs).

主权项

1. A laser line generator system for generating an elongated homogenous line illumination pattern on an illumination plane, the system comprising:
a plurality of diode lasers, each diode laser configured to emit coherent light having a slow-axis that is aligned in a slow-axis direction; and an optical system including:
a light guide positioned to receive said coherent light generated by said plurality of diode lasers, said light guide comprising a optically transparent dielectric material including side walls configured such that the side walls cause total internal reflection of said coherent light propagating through the optically transparent dielectric material, whereby said coherent light is mixed such that substantially homogenous light having intensity variations of less than 10% exits said light guide;at least one slow-axis relay lens positioned between the light guide and the illumination plane and configured to image said homogenized light exiting said light guide such that the homogenous light forms said homogenous line illumination pattern with an elongated line width extending in the slow-axis direction on said illumination plane.