Abstract: A stack of parallel but laterally separated laser beams emitted from a pair of laterally separated laser diode bars are focused into a single vertical plane through the use of an interleaved array of stacked, angular glass plates. Successive plates oppositely refract laser beams from successive radiating levels of the stacks of laser bars so that beams emerging from the glass plates lie in the same vertical plane, thereby overcoming the lateral displacement among beams emerging from the laser bars.

Abstract: The screening of edge-emitting laser diode bars in a production line is permitted by fabricating the source electrodes of each diode in the bar in two parts spaced apart to form a window aligned with the lasing cavity of the diode. Such windows have been made in failed devices to determine the cause of failure. Here, the windows are formed in a wafer stage of fabrication for later separation into laser bars or individual laser diodes. All wafers, all laser bars and all laser diodes are fabricated with windows thus permitting automatic screening during fabrication rather than opening a window to examine only failed devices as is the case in the prior art.

Abstract: A laser diode or laser diode bar mounted on a heat sink and having an insulating layer of greater thickness also mounted on the heat sink requires a lead overlying both the insulating layer and the diode to bend downward for making electrical contact. Failures have been found to occur at the bend. The provision of a pattern of slots at the bend alleviates the problem by reducing stress there. The use of such slotted leads is disclosed for diodes or diode bars individually or in a stack arrangement.

Abstract: The cleavage of semiconductor crystalline wafers into laser diodes or laser diode bars is carried out at a low temperature at which both the semiconductor crystal substrate and the laser-forming laminate structure thereon are imbrittled. Cleavage at such low temperatures permits the cleavage planes to be closer together than was hitherto possible. A thickness to cavity length ratio of the resulting laser diodes or laser diode bars is approximately 1 as a result compared to 3/4 by prior art techniques. Also, the energy required for cleaving is reduced thus ensuring mirror surfaces at the cleavage planes.

Abstract: An array of laser diodes, or laser diode bars, is formed by positioning adjacent diodes or bars in an offset or staircase arrangement where the emitting facets of adjacent diodes, or bars, are in different planes. The offset arrangement permits the light from adjacent facets to be separated a distance q much shorter than permitted by prior art stacking arrangements because thermal and mechanical constraints characteristic of prior art stacks, are relaxed considerably in the offset arrangement. Power densities of 2000 watts/cm.sup.2 (cw) are achieved with spacings of 0.6 mm between adjacent laser bars, a ten fold increase in power density over in-plane (prior art) positioning of like components.

Abstract: Laser diode bars with a plurality of light emitting facets have the light from those facets coupled into corresponding fibers of a fiber optic bundle via a microlens having a superconic cross section. An improvement in energy coupling of the typically less than 85 percent to up to 95 percent is achieved.