Abstract: Continuous mass flow gas replenishment may be implemented in a gas lasing device, such as a gas laser or amplifier, by using a restrictive orifice to bleed one or more gases into a reservoir and/or discharge chamber of the gas laser or amplifier at a predefined mass flow rate. The mass flow rate is a function of the pressure drop across the restrictive orifice resulting from the pressure differential between the depleted gas and the source gas. Thus, gases may be added as needed such that the gas total pressure, as well as the constituent partial pressures, is maintained within a desired range throughout the laser or amplifier fill lifetime. The continuous mass flow gas replenishment may thus make up the lost partial pressure of reactive gases in gas lasing devices in a manner that is less complicated and is less expensive than other continuous flow methodologies.

Abstract: Vision correction and tracking systems may be used in laser machining systems and methods to improve the accuracy of the machining. The laser machining systems and methods may be used to scribe one or more lines in large flat workpieces such as solar panels. In particular, laser machining systems and methods may be used to scribe lines in thin film photovoltaic (PV) solar panels with accuracy, high speed and reduced cost. The vision correction and/or tracking systems may be used to provide scribe line alignment and uniformity based on detected parameters of the scribe lines and/or changes in the workpiece.

Abstract: Vision correction and tracking systems may be used in laser machining systems and methods to improve the accuracy of the machining. The laser machining systems and methods may be used to scribe one or more lines in large flat workpieces such as solar panels. In particular, laser machining systems and methods may be used to scribe lines in thin film photovoltaic (PV) solar panels with accuracy, high speed and reduced cost. The vision correction and/or tracking systems may be used to provide scribe line alignment and uniformity based on detected parameters of the scribe lines and/or changes in the workpiece.

Abstract: Laser lift off systems and methods overlap irradiation zones to provide multiple pulses of laser irradiation per location at the interface between layers of material to be separated. To overlap irradiation zones, the laser lift off systems and methods provide stepwise relative movement between a pulsed laser beam and a workpiece. The laser irradiation may be provided by a non-homogeneous laser beam with a smooth spatial distribution of energy across the beam profile. The pulses of laser irradiation from the non-homogenous beam may irradiate the overlapping irradiation zones such that each of the locations at the interface is exposed to different portions of the non-homogeneous beam for each of the multiple pulses of the laser irradiation, thereby resulting in self-homogenization. Thus, the number of the multiple pulses of laser irradiation per location is generally sufficient to provide the self-homogenization and to separate the layers of material.

Abstract: Laser machining systems and methods may include debris removal systems to remove debris generated by the machining process and/or outgassing or filtration systems to remove harmful gases and filter and recycle air within the system. The laser machining systems and methods may be used to scribe one or more lines in large flat workpieces such as solar panels. In particular, laser machining systems and methods may be used to scribe lines in thin film photovoltaic (PV) solar panels with accuracy, high speed and reduced cost.

Abstract: A pre-irradiation system and method may be used in a gas discharge lasing device to provide multiple ultraviolet (UV) pre-irradiation discharges per electrical feed-through into a gas discharge chamber of the lasing device. One or more high-voltage electrical feed-throughs are electrically connected to one or more high-voltage electrodes that provide multiple discharge paths to a current return electrode to allow multiple pre-irradiation discharges per feed-through in response to high-voltage pulses applied via the feed-through(s). The discharge paths may include spark gap discharge paths and/or tracking discharge paths across an insulator. In some embodiments, multiple discharge paths are formed between respective tracking locators on a high voltage electrode and/or a current return electrode. In other embodiments, multiple discharge paths are formed between respective discharge locations on a high voltage electrode surrounded by an insulator, which spark or track to a current return electrode.

Abstract: A system and method of laser machining rotates a workpiece about an axis of rotation, and translates the workpiece in a first direction along the axis of rotation. A mask defining a shape is translated in a second direction opposite the first direction, and a laser beam is directed at the mask such that the laser beam is scanned across the mask and at least a portion of the laser beam passes through the mask and toward the workpiece. The mask and the workpiece are translated with coordinating opposing motion to cause the laser beam to be imaged onto the workpiece with a shape or pattern corresponding to a shape or pattern defined by the mask. Rotation of the workpiece and the shape of the image on the workpiece produce different vectorial intensities such that material of the workpiece is removed to different respective depths to form a three-dimensional structure.

Abstract: An adjustable astigmatic elongated beam spot may be formed from a laser beam having ultrashort laser pulses and/or longer wavelengths to machine substrates made of a variety of different materials. The laser beam may be generated with pulses having a pulse duration of less than 1 ns and/or having a wavelength greater than 400 nm. The laser beam is modified to produce an astigmatic beam that is collimated in a first axis and converging in a second axis. The astigmatic beam is focused to form the astigmatic elongated beam spot on a substrate, which is focused on the substrate in the first axis and defocused in the second axis. The astigmatic elongated beam spot may be adjusted in length to provide an energy density sufficient for a single ultrashort pulse to cause cold ablation of at least a portion of the substrate material.

Abstract: A variable astigmatic focal beam spot is formed using lasers with an anamorphic beam delivery system. The variable astigmatic focal beam spot can be used for cutting applications, for example, to scribe semiconductor wafers such as light emitting diode (LED) wafers. The exemplary anamorphic beam delivery system comprises a series of optical components, which deliberately introduce astigmatism to produce focal points separated into two principal meridians, i.e. vertical and horizontal. The astigmatic focal points result in an asymmetric, yet sharply focused, beam spot that consists of sharpened leading and trailing edges. Adjusting the astigmatic focal points changes the aspect ratio of the compressed focal beam spot, allowing adjustment of energy density at the target without affecting laser output power. Scribing wafers with properly optimized energy and power density increases scribing speeds while minimizing excessive heating and collateral material damage.

Abstract: Continuous mass flow gas replenishment may be implemented in a gas lasing device, such as a gas laser or amplifier, by using a restrictive orifice to bleed one or more gases into a reservoir and/or discharge chamber of the gas laser or amplifier at a predefined mass flow rate. The mass flow rate is a function of the pressure drop across the restrictive orifice resulting from the pressure differential between the depleted gas and the source gas. Thus, gases may be added as needed such that the gas total pressure, as well as the constituent partial pressures, is maintained within a desired range throughout the laser or amplifier fill lifetime. The continuous mass flow gas replenishment may thus make up the lost partial pressure of reactive gases in gas lasing devices in a manner that is less complicated and is less expensive than other continuous flow methodologies.

Abstract: Laser machining systems and methods may use one or more moving laser scanning stages with force cancellation. The force cancellation is provided by moving masses linearly with equal and opposition motion. One or more of the masses may be a laser scanning stage. The laser machining systems may be used to scribe one or more lines in large flat workpieces such as solar panels. In particular, laser machining systems and methods may be used to scribe lines in thin film photovoltaic (PV) solar panels with accuracy, high speed and reduced cost.

Abstract: Multiple beamlet laser beam delivery systems and methods may be used in laser machining systems and methods to machine multiple regions on a workpiece simultaneously. One embodiment of a laser machining system and method may be used, for example, to scribe one or more lines in large flat workpieces such as solar panels. In particular, laser machining systems and methods may be used to scribe lines in thin film photovoltaic (PV) solar panels with accuracy, high speed and reduced cost. The multiple beam delivery systems may be movable to scribe multiple lines simultaneously in the workpiece.

Abstract: A laser machining system and method uses a shaped laser beam, such as a long, narrow beam, and effectively scans the beam in the narrow direction across a mask having an aperture pattern. The pattern on the mask is imaged onto a moving workpiece and the patterned laser beam selectively removes material from the workpiece. The workpiece may be moved using a coordinated synchronized rotational motion. The laser may use a longer wavelength (e.g., 248 nm) and the beam may be scanned at a high rate of speed to reduce the dissipation of the residual thermal energy in the material being machined. In one embodiment, this system and method may be used to machine a complex pattern into a curved surface with relatively high resolution and high speeds.