Abstract:
A laser beam switching system (50) employs a laser (52) coupled to a beam switching device (58) that causes a laser beam to switch between first and second beam positioning heads such that while the first beam positioning head (60) is directing the laser beam to process a workpiece target location, the second beam positioning head (62) is moving to another target location and vice versa. A preferred beam switching device includes first and second AOMs. When RF is applied to the first AOM (72), the laser beam is diffracted toward the first beam positioning head, and when RF is applied to the second AOM (74), the laser beam is diffracted toward the second beam positioning head. A workpiece processing system (120) employs a common modular imaged optics assembly (122) and an optional variable beam expander (94) for optically processing multiple laser beams.
Abstract:
A laser beam switching system (50) employs a laser (52) coupled to a beam switching device (58) that causes a laser beam to switch between first and second beam positioning heads such that while the first beam positioning head (60) is directing the laser beam to process a workpiece target location, the second beam positioning head (62) is moving to another target location and vice versa. A preferred beam switching device includes first and second AOMs. When RF is applied to the first AOM (72), the laser beam is diffracted toward the first beam positioning head, and when RF is applied to the second AOM (74), the laser beam is diffracted toward the second beam positioning head. A workpiece processing system (120) employs a common modular imaged optics assembly (122) and an optional variable beam expander (94) for optically processing multiple laser beams.
Abstract:
Embodiments of laser systems advantageously use pulsed optical fiber-based laser source (12) output, the temporal pulse profile of which may be programmed to assume a range of pulse shapes. Pulsed fiber lasers are subject to peak power limits to prevent an onset of undesirable nonlinear effects; therefore, the laser output power of these devices is subsequently amplified in a diode-pumped solid state photonic power amplifier (DPSS-PA) (16). The DPSS PA provides for amplification of the desirable low peak power output of a pulsed fiber master oscillator power amplifier (14) to much higher peak power levels and thereby also effectively increases the available energy per pulse at a specified pulse repetition frequency. The combination of the pulsed fiber master oscillator power amplifier and the diode-pumped solid state power amplifier is referred to as a tandem solid state photonic amplifier (10).
Abstract:
Embodiments of laser systems advantageously use pulsed optical fiber-based laser source (12) output, the temporal pulse profile of which may be programmed to assume a range of pulse shapes. Pulsed fiber lasers are subject to peak power limits to prevent an onset of undesirable nonlinear effects; therefore, the laser output power of these devices is subsequently amplified in a diode-pumped solid state photonic power amplifier (DPSS-PA) (16). The DPSS PA provides for amplification of the desirable low peak power output of a pulsed fiber master oscillator power amplifier (14) to much higher peak power levels and thereby also effectively increases the available energy per pulse at a specified pulse repetition frequency. The combination of the pulsed fiber master oscillator power amplifier and the diode-pumped solid state power amplifier is referred to as a tandem solid state photonic amplifier (10).
Abstract:
Preferred embodiments of a purge gas port (74), laser beam attenuating input window (24), and laser shutter (20) constitute subsystems of a UV laser optical system (10) in which a laser beam is completely enclosed to reduce contamination of the optical system components (42, 60, 72). Purge gas is injected through multiple locations in a beam tube assembly (18) to ensure that the optical component surfaces (78) sensitive to contamination are in the flow path of the purge gas. The input window functions as a fixed level attenuator to limit photopolymerization of airborne molecules and particles. Periodically rotating optical elements asymmetrically in their holders (142) reduces burn damage to the optics.
Abstract:
Preferred embodiments of a purge gas port (74), laser beam attenuating input window (24), and laser shutter (20) constitute subsystems of a UV laser optical system (10) in which a laser beam is completely enclosed to reduce contamination of the optical system components (42, 60, 72). Purge gas is injected through multiple locations in a beam tube assembly (18) to ensure that the optical component surfaces (78) sensitive to contamination are in the flow path of the purge gas. The input window functions as a fixed level attenuator to limit photopolymerization of airborne molecules and particles. Periodically rotating optical elements asymmetrically in their holders (142) reduces burn damage to the optics.
Abstract:
A laser (126) and an AOM (10) are pulsed at substantially regular and substantially similar constant high repetition rates to provide working laser outputs (40) with variable noimpingement intervals (50) without sacrificing laser pulse-to-pulse energy stability. When a working laser output (40) is demanded, an RF pulse (38) is applied to the AOM (10) in coincidence with the laser output pulse (24) to transmit the laser pulse to a target. When no working laser output (40) is demanded, an RF pulse (38) is applied to the AOM (10) in noncoincidence with the laser output (24), so that the laser pulse is blocked. Thus, the average thermal loading on the AOM (10) remains substantially constant regardless of how randomly the working laser outputs (40) are demanded. The AOM (10) can also be employed to control the energy of the working laser output (40) by controlling the power of the RF pulse (38) applied. When the RF power is changed, the duration (44) of the RF pulse (38) is modified to maintain the constant average RF power.