Abstract: A dye laser comprising a container retaining a dye solution for laser and an energy source for pumping connected to the container, the dye solution containing a pyrazoloazaxanthenoisoquinolinone dye.

Abstract: A laser cooling system has a coolant formulated to act as a heat exchanger and a transparent optical medium of matching refractive index between the flashlamp, silver reflectors and laser rod. The coolant has one or more fluorescent dyes and an inorganic pH buffering additive therein and the lamp is in a cerium doped envelope. A method is provided for measuring the operation time of a laser having a cooling system and a coolant having fluorescent dyes therein and actuating a solenoid valve after a predetermined operational life of the laser to release a dye additive into the coolant to maintain the efficiency of the laser.

Abstract: A dye laser (FIG. 1, 5 or 6) includes a pumping laser source (e.g. 11), an optical resonator (e.g. 13-15), and a dye solution or dye cell (e.g. 12) disposed in the path of the pumping laser light in the resonator. The dye cell disclosed herein comprises a pair of closely spaced transparent discs (21). A motor (26) serves to spin the discs at a high rate of speed. The pumping laser light in the resonator is focused on the discs at a predetermined angle (i.e. the Brewster angle). New, unbleached dye is injected axially with respect to the discs so that the spin force causes a radial flow of the dye solution between the spinning discs and, of course, past the pumping laser light spot.

Abstract: A hybrid laser resonator for use with a transverse flow waveguide laser includes cylindrical optical elements for coupling together regions of a thin slab-shaped laser medium operating in the waveguide mode through a set of reflectors which define the ends of the laser cavity. Separate waveguide cylindrical optics which focus in the thin dimension of the slab are combined with a negative cylindrical lens which diverges in the thick dimension of the slab. The negative lens causes an unstable resonator condition to exist in the thick or fluid flow direction so as to prevent narrow isolated horizontal lasing bands and thus provide a nearly diffraction limited beam quality in both thick and thin dimensions.

Abstract: A method and apparatus for producing stable and reproducible ultra-short lasing radiation pulses are disclosed. The duration of incoming pumping pulses for the dye laser arrangement is reduced in stages to produce the ultra-short pulses. A first dye laser cavity of a series of at least two cascaded dye laser cavities is excited with lasing radiation pulses. The lasing radiation pulses emerging from each dye laser cavity of the series are directed into the next successive dye laser cavity of the series. The photon cavity lifetime of each dye laser cavity of the series is sufficient for a given duration of the incoming pumping pulses to produce the ultra-short pulses emerging from the final dye laser cavity of the series. The maximum photon cavity lifetime of each dye laser cavity of the series is selected to thereby reduce in stages the duration of the incoming pumping pulses. This reduction yields from the final dye laser cavity of the series the ultra-short lasing radiation pulses.

Abstract: A dye cell holder adapted for removable engagement with a support in a dye laser arrangement is disclosed. The holder is particularly adapted to hold thin fragile dye cells. The holder comprises means for supporting such fragile cell which contains a dye solution and is to be pumped by a laser beam. The dye cell is retained against the support by a retaining means which is movable relative to the support in a manner to provide access to permit insertion of the dye cell into the holder and to permit removal of the cell from the support means.

Abstract: A dye laser having an improved dye jet nozzle and its method of manufacture is described. The exit aperture of the nozzle is provided by a nozzle end assembly made up of a plurality of blocks of material which are in optical contact with one another. The liquid channel defined by the blocks is provided with optically flat surfaces which minimize interference with uniform liquid flow therethrough. Moreover, edges are provided for the exit aperture defined by the blocks by polishing the same while they are supported, so that the resulting edges have a minimum of imperfections.

Abstract: A long rare-gas halide excimer light source excited by a capacitively coupled discharge pumps a dye laser with high efficiency in a configuration matched to the length of the discharge.

Abstract: A laser dye, 2-keto-4,6,8,8-tetramethyl-8,9-dihydro-2H-pyrano(3,2-g) quinoline, is prepared by mixing m-aminophenol and ethyl acetoacetate and heating the mixture.

Abstract: A dye solution reservoir system for a dye laser comprises a dye solution reservoir, main fluid circuit means for circulating dye solution between the reservoir and a dye laser, and a by-pass dye replenishment loop between the reservoir and the laser for (1) diverting a portion of the solution from the main circuit, (2) filtering substantially all solute, including the dye and other particles from that portion of the solution, (3) replenishing the solution by adding fresh dye solute, and (4) returning the replenished solution to the main circuit. In a preferred embodiment, the solution is filtered by a first filter for removing the dye solute and a second filter for removing degradation by-products and particulate matter. Reverse osmosis may be advantageously used as a part of this filtrate system. The advantage of such systems is a substantial reduction in the required reservoir capacity and enhanced dye recoverability.

Abstract: Fluorescent dyestuffs of the general formula ##STR1## wherein R and R.sup.1 independently of one another represent hydrogen, a salt-forming cation, an alkyl radical with 1 to 16 C atoms or an aryl or aralkyl radical which is optionally substituted by non-chromophoric groups,R.sup.2 to R.sup.5 independently of one another represent hydrogen, alkyl, trifluoromethyl, alkoxy, aralkoxy, alkenoxy, aryloxy, halogen or a carboxyl, cyano, alkyl sulphone, aryl sulphone, aralkyl sulphone, carboxamide, sulphonamide or carboxylic acid ester group,o, p, q and s independently of one another represent 1 or 2 andm and n independently of one another denote 0, 1 or 2, it being possible for the sum of m and n to be 2 to 4,processes for their preparation and their use as laser dyestuffs.

Abstract: Distyryl compounds of the formula ##STR1## wherein A denotes 1,4-phenylene, 4,4'-biphenylylene, 4,4"-terphenylylene, 1,4-, 1,5- or 2,6-naphthylene, 9,10-dihydro-2,7-phenanthrenylene or 2,7-dibenzofuranylene,R.sup.1 denotes an optionally functionally modified phosphonic acid, phosphonyl or phosphinyl group,R.sup.2 denotes hydrogen, an optionally functionally modified phosphonic acid, phosphonyl or phosphinyl group, sulpho, carboxyl, alkoxycarbonyl, aryloxycarbonyl, aralkoxycarbonyl, aminocarbonyl, cyano, halogen, alkyl, aralkyl, alkenyl, hydroxyl, alkoxy, aralkoxy, cycloalkoxy, aryloxy or alkylmercapto andR.sup.3 and R.sup.