초록 ▼

A laser diode illuminator device and a method for optically conditioning the output beam radiated from such a device, so that highly-demanding illumination application requirements that call for high output powers within a specified field of illumination can be addressed. At the heart of the device

A laser diode illuminator device and a method for optically conditioning the output beam radiated from such a device, so that highly-demanding illumination application requirements that call for high output powers within a specified field of illumination can be addressed. At the heart of the device is a two-dimensional stack of laser diode bars wherein the linear array of beamlets radiated by each laser diode bar is optically conditioned through its passage in a refractive-type micro-optics device followed by a cylindrical microlens. The micro-optics device performs collimation of the linear array of beamlets along the fast axis of the bars, and it also acts as a beam symmetrization device by interchanging the divergences of the laser beamlets along the fast and slow axes. The cylindrical microlens is for collimation of the beamlets along the slow axis. The optical conditioning is performed individually for each linear array of beamlets so that the radiance or brightness of the laser diode illuminator can be optimized while any specified field of illumination can be filled with an excellent uniformity of the radiant intensity.

대표청구항 ▼

The invention claimed is: 1. A laser diode apparatus for illumination, said apparatus comprising:(a) a plurality of laser diode bars packaged in the form of at least one stacked laser diode array, said at least one array radiating a two-dimensional array of laser beamlets,(b) a plurality of micro-op

The invention claimed is: 1. A laser diode apparatus for illumination, said apparatus comprising:(a) a plurality of laser diode bars packaged in the form of at least one stacked laser diode array, said at least one array radiating a two-dimensional array of laser beamlets,(b) a plurality of micro-optics devices for perfoming collimation of the beamlets along the fast axis of said laser diode bars and for interchanging divergence angles of said beamlets along the orthogonal fast and slow axes, the number of said micro-optics devices being equal to the number of said laser diode bars,(c) a plurality of cylindrical microlenses elongated along a direction parallel to said diode laser bars for performing collimation along the slow axis of the beamlets exiting from said micro-optics devices, the number of said cylindrical microlenses being equal to the number of said laser diode bars and their spacing being equal to the spacing between said diode laser bars, and their maximum diameter being determined by the spacing between said laser diode bars,(d) a support structure having a front face on which said plurality of cylindrical microlenses are bonded, said support structure being attached to said array of laser diode bars and said support structure securing said plurality of cylindrical microlenses, said support structure providing spacing between said plurality of cylindrical microlenses and said array of laser diode bars so that the plane of emission of said array of laser diode bars is substantially in the back focal plane of said cylindrical microlenses,(e) means for supplying electrical power to said at least one stacked laser diode array and for controlling its operation,(f) means for controlling the operating temperature of said at least one stacked laser diode array,wherein the interchange of the divergence angles of said array of laser beamlets performed by said plurality of micro-optics devices provides for the use of cylindrical microlenses having their focal length long enough to provide collimation with a predetermined residual divergence angle along the slow axis of said array of laser beamlets.