as illustrated at 73 due to a self signature laser diode bars constructed with multiple single emitter laser diodes are illustrated in fig1 to be bonded to a circular conductive bond plate 72 with the laser diode bars 70 positioned on either side of ring 30 as can be seen in fig1 conductive plates 72 are positioned on a hollow thermally conductive substrate 74 that provides a chamber 76 between the top and bottom conductive plates this structure along with central aperture 78 in the disk assembly provides for a centrally located cooling chamber for each of the rings as well as to provide for passage of airflow through the disks for cooling purposes as can be seen in fig1 with the diode bars 70 mounted to rings 30 the staring field of view for each of the individual or single element diode lasers is about 40 u00b0 in the vertical direction and about 12 u00b0 in the horizontal direction as will be appreciated with the laser diode bars located on the periphery of a ring one achieves 360 u00b0 coverage here illustrated by double ended arrow 80 the vertical coverage is illustrated by double ended arrow 78 and the horizontal coverage is illustrated by double ended arrow 79 in order to extend the vertical coverage of the semiconductor ir source to a virtual sphere as shown in fig2 ring 30 u2032 and 30 u2033 are dish shaped in which one of the rings is upwardly bowed.