Abstract: A dye laser is of compact, rigid and simple construction, with a folded resonator cavity contained on a single rigid block of material, such as aluminum. The block has two or three mirror mount locations, at least one of which is a machined surface which receives a mirror directly and rigidly, without provision for adjustment. The other mirror mount location(s) has an adjustable mirror mount, and this may be the mirror mount for the output mirror. A dye jet mounting block has a flat surface which engages against a flat surface on the exterior of the laser block, with fasteners allowing for rotation and translation of the dye jet block on the laser resonator block to provide for both rotational and translational tuning adjustment of the dye jet with respect to the resonator cavity and a pumping beam. The pumping beam preferably is folded by an adjustable pump mirror on its approach to the dye jet.

Abstract: The power output of a gas laser is maximized by (1) suppressing high order transverse modes, (2) broadening the gain curve to increase the number of axial modes that can lase in a given length of cavity and to thereby reduce power variation due to longitudinal mode sweeping resulting from thermal effects on cavity length, (3) suppressing unwanted infrared lasing activity, and (4) reducing beating noise resulting from frequency offset due to dispersion.

Abstract: A capillary bore laser tube is constructed to have little or no power loss when subjected to relatively high shock loads during operation. A spider structure supports the free end of the capillary bore tube in an almost rigid manner against transverse movement of the free end with respect to the outer envelope or jacket of the laser tube so that high shock loads and vibration produce little or no permanent change in the radial alignment of the free end of the bore tube with respect to the other operating components of the laser tube. The spider structure is a disk shaped member which is rigidly attached at its outer periphery to the outer envelope and which is also rigidly attached at its inner periphery to the bore tube. The spider structure is sufficiently flexible in a longitudinal direction to accommodate differential thermal expansion resulting from the differences in temperatures between the bore tube and the outer envelope produced when the laser is energized for operation.

Abstract: A cold cathode gas discharge apparatus, of the kind in which ionized species are driven against a cathode by an electrical field to eject electrons from the cathode and to produce a discharge within a gas discharge confinement tube, has a cathode constructed for balancing the trapping rate and releasing rate of gas particles in the cathode to maintain a substantially constant gas pressure during the operating life of the gas discharge apparatus. The cathode has an active surface which forms a substantially reentrant cavity about the end of the gas discharge confinement tube.