Abstract: A long pulsed dye laser device for selective photothermolysis comprises at least two pulsed dye lasers, such as flash lamp excited dye lasers, each generating corresponding pulsed laser beams successively in time. These laser can be coordinated by a synchronizer that sequentially triggers the lasers. A combining network merges the pulse laser beams into a combined beam and a delivery system conveys the combined pulse laser beam to a patient. An example of a delivery device is a single optical fiber. This invention enables production of the necessary pulse widths, on the order of 2 msec, which can not be achieved by individual dye lasers, generally lower than 0.8 msec. Also disclosed is a selective photothermolysis method. This method comprises irradiating a tissue section of a patient with a pulsed laser beam having a changing color across a time period of the pulse.

Abstract: In a dye laser system, a porous bed filter is loaded with dye prior to operation of the system. With repeated firings, the dye solution is filtered by the porous bed filter to remove by-products of the laser process. Solute concentration is monitored and dye and additives removed by the filter are replenished by a metering pump. Precise temperature control assures consistent filtering of dye by the filter for more consistent color and energy output. To control the metering pump, the differential output of a two-channel absorption detector is digitized. The digitized signal is loaded into a counter which drives the metering pump. The useful lifetime of the dye solution is enhanced by incorporating pH buffers in the solution.

Abstract: A long pulsed dye laser device for selective photothermolysis comprises at least two pulsed dye lasers, such as flash lamp excited dye lasers, each generating corresponding pulsed laser beams successively in time. These laser can be coordinated by a synchronizer that sequentially triggers the lasers. A combining network merges the pulse laser beams into a combined beam and a delivery system conveys the combined pulse laser beam to a patient. An example of a delivery device is a single optical fiber. This invention enables production of the necessary pulse widths, on the order of 2 msec, which can not be achieved by individual dye lasers, generally lower than 0.8 msec. Also disclosed is a selective photothermolysis method. This method comprises irradiating a tissue section of a patient with a pulsed laser beam having a changing color across a time period of the pulse.

Abstract: A long pulsed dye laser device for selective photothermolysis comprises at least two pulsed dye lasers, such as flash lamp excited dye lasers, each generating corresponding pulsed laser beams successively in time. These laser can be coordinated by a synchronizer that sequentially triggers the lasers. A combining network merges the pulse laser beams into a combined beam and a delivery system conveys the combined pulse laser beam to a patient. An example of a delivery device is a single optical fiber. This invention enables production of the necessary pulse widths, on the order of 2 msec, which can not be achieved by individual dye lasers, generally lower than 0.8 msec. Also disclosed is a selective photothermolysis method. This method comprises irradiating a tissue section of a patient with a pulsed laser beam having a changing color across a time period of the pulse.

Abstract: In a dye laser system, a porous bed filter is loaded with dye prior to operation of the system. With repeated firings, the dye solution is filtered by the porous bed filter to remove by-products of the laser process. Solute concentration is monitored and dye and additives removed by the filter are replenished by a metering pump. Precise temperature control assures consistent filtering of dye by the filter for more consistent color and energy output. To control the metering pump, the differential output of a two- channel absorption detector is digitized. The digitized signal is loaded into a counter which drives the metering pump. The useful lifetime of the dye solution is enhanced by incorporating pH buffers in the solution.

Abstract: A method for treating simple wrinkles caused by age or sun exposure comprises treating blood vessels in the wrinkles with laser light. The laser light may have a wavelength between 577 and 585 nm. The laser light may also be a laser light pulse having a pulse duration that is greater than 0.2 msec, or alternatively, greater than 0.5 msec. The output pulse may be generated with a dye laser, for instance, by exciting dye solution in a resonant cavity with one or more flashlamps. A further treatment method comprises irradiating wrinkle-bearing skin with a laser pulse where the pulse duration is selectively matched to the thermal relaxation time of blood vessels in the targeted skin.

Abstract: In a dye laser system, a porous bed filter is loaded with dye prior to operation of the system. With repeated firings, the dye solution is filtered by the porous bed filter to remove by-products of the laser process. Solute concentration is monitored and dye and additives removed by the filter are replenished by a metering pump. Precise temperature control assures consistent filtering of dye by the filter for more consistent color and energy output. To control the metering pump, the differential output of a two-channel absorption detector is digitized. The digitized signal is loaded into a counter which drives the metering pump. The useful lifetime of the dye solution is enhanced by incorporating pH buffers in the solution.

Abstract: A long pulsed dye laser device for selective photothermolysis comprises at least two pulsed dye lasers, such as flash lamp excited dye lasers, each generating corresponding pulsed laser beams successively in time. These lasers can be coordinated by a synchronizer that sequentially triggers the lasers. A combining network merges the pulse laser beams into a combined beam and a delivery system conveys the combined pulse laser beam to a patient. An example of a delivery device is a single optical fiber. This invention enables production of the necessary pulse widths, on the order of 2 msec, which can not be achieved by individual dye lasers, generally lower than 0.8 msec. Also disclosed is a selective photothermolysis method. This method comprises irradiating a tissue section of a patient with a pulsed laser beam having a changing color across a time period of the pulse.

Abstract: In a dye laser system, a porous bed filter is loaded with dye prior to operation of the system. With repeated firings, the dye solution is filtered by the porous bed filter to remove by-products of the laser process. Solute concentration is monitored and dye and additives removed by the filter are replenished by a metering pump. Precise temperature control assures consistent filtering of dye by the filter for more consistent color and energy output. To control the metering pump, the differential output of a two-channel absorption detector is digitized. The digitized signal is loaded into a counter which drives the metering pump. The useful lifetime of the dye solution is enhanced by incorporating pH buffers in the solution.

Abstract: A flashlamp-excited dye laser generating light pulses for therapy has a circulator which circulates a gain media through a dye cell. A controller coordinates operation by triggering flashlamps to excite the laser gain media while the circulator is circulating the gain media. This operation enables the generation of laser light pulses with a duration of at least one millisecond. If the flow velocity of dye solution is great enough such that the new solution enters the resonant cavity before the solutions in the cavity are substantially spent, ultra-long pulses with high fluences are possible. Specifically, longer pulses of up to 50 msec can be achieved with energies of up to 50 Joules. These energies enable reasonable spot sizes, which makes the invention relevant to dermal therapy, for example.

Abstract: An optics X-Y positioner has an optics support positioned within a housing having sides and front and rear walls. The optics support has a groove on one face which rides in an X direction along a ridge in a sliding guide plate. The guide plate slides within a flat groove in the Y direction in the rear wall of the housing. X and Y direction adjustment screws extend through sides of the frame and abut the optics support. A spring in tension is wrapped about the optics support in a circumferential groove to force the optics support against the adjustment screws.

Abstract: A dye laser fluid dye solution replenishment system in which the portion of the lasing fluid passing through the laser head which has been activated to a lasing condition is separated from the remainder of the unactivated dye solution and is separately restored before being recombined into the fluid flow path. The thus separated and degraded dye solution, representing only the degraded component of the flowing dye solution, is filtered to remove the degradation products and restored to the desired dye solution component concentrations. The thus restored solution is reinserted into the fluid flow path through the laser head.

Abstract: Automated gain control in rail flaw detection which includes attenuation of echoes from rails pulsed with a burst of sonic energy, comparing said attenuated signals over discrete intervals, and reducing or increasing said attenuation in response thereto to develop a uniform signal from which an evaluation of flaw indicating echoes can be obtained.

Abstract: An automatic base gate positioning circuit for use in rail flaw detection is disclosed which includes the generation of a string of uniformly spaced pulses corresponding to known rail depth, correlating said pulses with sonic echoes averaging and storing the correlated signals and developing a signal representing the rail depth for comparison with an echo from the rail base.