Cylindrical microlens with an internally reflecting surface and a method of fabrication

#1. Field of the Invention

#The present invention relates to microlenses. More specifically, the present invention relates to cylindrical microlenses for use with laser diodes, laser diode bars, and integrated optics.

#2. Description of Related Art

#The accompanying drawings, which are incorporated into and form a part of the disclosure, illustrate an embodiment of the invention and, together with the description, serve to explain the principles of the invention.

#FIG. 1 illustrates a cylindrical lens.

#FIG. 2 shows the basic concept of non-normal emission from a multitude of laser diode bars attached to plane surfaces in silicon V-grooves, where the plane surfaces are defined by <111> planes.

#General Description

#The prior art cylindrical-technology (i.e., shaped fiber lenses) to condition large radiance conditioned laser diode array sources has centered on the development of a modular integrated laser diode package. One of the convenient features of large two-dimensional diode arrays constructed from this technology is the normal emission direction relative to the array face, (See R. J. Beach et al., “Applications of Micro-lens-conditioned Laser Diode Arrays,” SPIE, Vol. 2383, p. 283 (1995). However, subsequent technology, (i.e., Silicon Monolithic Microchannels (SiMM) and V-BASIS), which has kept many features of the modular integrated laser diode packages, does not have the normal emission feature because the diodes in these packages are attached to slanted surfaces defined by the V-grooves that are due to anistropic etching of silicon wafers.

#FIG. 1 illustrates a conventional cylindrical lens 10, comprising a body 11, having a first surface 12 and a second surface 14. As illustrated in FIG. 1, light rays 18 enter the body 11 of the cylindrical lens 10 through the first surface 12, and exit the lens 10 through the second surface 14. In other configurations, the direction of light propagation may be reversed.