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A precision, laser-based method and system for high-speed, sequential processing of material of targets within a field are disclosed that control the irradiation distribution pattern of imaged spots. For each spot, a laser beam is incident on a first anamorphic optical device and a second anamorphic

A precision, laser-based method and system for high-speed, sequential processing of material of targets within a field are disclosed that control the irradiation distribution pattern of imaged spots. For each spot, a laser beam is incident on a first anamorphic optical device and a second anamorphic optical device so that the beam is controllably modified into an elliptical irradiance pattern. The modified beam is propagated through a scanning optical system with an objective lens to image a controlled elliptical spot on the target. In one embodiment, the relative orientations of the devices along an optical axis are controlled to modify the beam irradiance pattern to obtain an elliptical shape while the absolute orientation of the devices controls the orientation of the elliptical spot.

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1. A high-speed, precision, laser-based method for processing material of at least one target within a field, the method comprising:generating a laser beam along a propagation path;controllably modifying the laser beam to obtain a modified laser beam; andsequentially and relatively positioning the m

1. A high-speed, precision, laser-based method for processing material of at least one target within a field, the method comprising:generating a laser beam along a propagation path;controllably modifying the laser beam to obtain a modified laser beam; andsequentially and relatively positioning the modified laser beam into at least one well-focused spot at each target within the field to process the material of each target wherein the at least one spot has a set of desired spatial characteristics including an adjustable aspect ratio which are obtained by the step of controllably modifying. 2. The method as claimed in claim 1, wherein the at least one well-focused spot has a pair of axes and wherein the modified laser beam is focused to a substantially common point in both axes. 3. The method as claimed in claim 1, wherein the adjustable aspect ratio is greater than 0.1 but less than 10. 4. The method as claimed in claim 3, wherein the adjustable aspect ratio is greater than 0.33 but less than 3. 5. The method as claimed in claim 1, wherein the step of sequentially and relatively positioning includes the step of vector scanning the modified laser beam. 6. The method as claimed in claim 1, wherein the step of controllably modifying the laser beam is repeated during the step of sequentially and relatively positioning the modified laser beam so that the at least one well-focused spot has at least a second set of desired spatial characteristics. 7. The method as claimed in claim 1, wherein the set of desired spatial characteristics is determined based on at least one target characteristic of each target. 8. The method as claimed in claim 1, wherein the set of desired spatial characteristics is determined based on at least one target material property of each target. 9. The method as claimed in claim 1, wherein the set of desired spatial characteristics is determined based on at least one process variable. 10. The method as claimed in claim 1, wherein the set of desired spatial characteristics is determined based on at least one desired laser material processing characteristic. 11. The method as claimed in claim 1 wherein the step of generating includes the step of shaping the laser beam to change the aspect ratio and to obtain a modified beam having a first elongated irradiance pattern with a first orientation wherein the modified beam is delivered and focused into the at least one well-focused spot. 12. The method as claimed in claim 11, wherein the step of generating includes the step of further shaping the modified beam to obtain a laser beam having a second elongated irradiance pattern with a second orientation. 13. The method as claimed in claim 12, wherein the step of controllably modifying controls absolute orientation of the first and second orientations based on target orientation. 14. The method as claimed in claim 12, wherein the step of shaping further includes the step of controlling relative orientation of the first and second orientations. 15. The method as claimed in claim 1, wherein the step of sequentially and relatively positioning delivers and focuses the beam into a plurality of well-focused spots extending along a laser processing path wherein the aspect ratio and orientation of each of the spots is based on predetermined dimensions of each target and target orientation. 16. The method as claimed in claim 15, wherein the laser processing path is a curvilinear path. 17. The method as claimed in claim 15, wherein each of the well-focused spots is an elongated spot having a major axis and wherein the major axis of at least one of the spots is aligned with the laser processing path. 18. The method as claimed in claim 15, wherein each of the well-focused spots is an elongated spot having a major axis and wherein the major axis of at least one of the spots is transverse the laser processing path. 19. The method as claimed in claim 1, wherein an aspect ratio and orientation of the at least one spot are controlled bas ed on predetermined dimensions of each target and target orientation. 20. The method as claimed in claim 1, wherein the step of generating includes the step of filtering the laser beam to obtain an initially modified spot shape. 21. The method as claimed in claim 1, wherein the step of generating includes the step of filtering the laser beam to obtain an initially modified spot irradiance profile. 22. The method as claimed in claim 1, wherein the processing is micromachining. 23. The method as claimed in claim 1, wherein the processing includes semiconductor link removal, laser trimming, laser drilling or laser etching. 24. The method as claimed in claim 1, wherein the step of sequentially and relatively positioning delivers and focuses the modified beam into a well-focused spot which is scanned along a laser processing path wherein an aspect ratio and orientation of the spot is based on predetermined dimensions of each target and target orientation. 25. The method as claimed in claim 1, wherein the modified beam has an irradiance pattern of an elliptical Gaussian beam. 26. The method as claimed in claim 1, wherein the modified beam has an irradiance pattern of a top hat in one direction and Gaussian in a direction orthogonal to the one direction. 27. The method as claimed in claim 1, wherein multiple targets are within the field. 28. A high-speed, precision, laser-based method for processing material of at least one target within a field, the method comprising:a) generating a laser beam along a propagation path;b) controllably modifying the laser beam to obtain a modified laser beam;c) relatively positioning the modified laser beam into at least one well-focused spot at a target within the field to process the material of the target wherein the at least one well-focused spot has a set of desired spatial characteristics including an adjustable aspect ratio which are obtained by step b); andd) repeating steps a) through c) for each target until the material of all targets within the field are processed. 29. The method as claimed in claim 28 further comprising: e) evaluating at least one of process, material and target characteristics to obtain data wherein step b) is based on the data. 30. The method as claimed in claim 29, wherein step d) repeats steps a) through c) and step e) for each target until the material of all targets within the field are processed. 31. A high-speed, precision system for processing material of at least one target having predetermined dimensions and a characteristic within a field, the system comprising:a laser source for generating a laser beam along a propagation path and having an irradiance pattern with an aspect ratio and an orientation in a plane substantially perpendicular to the propagation path;a controller for generating control signals including orientation control signals based on the characteristic;a first subsystem disposed in the propagation path for shaping the laser beam based on the predetermined dimensions to change the aspect ratio and obtain a modified beam;a second subsystem for controllably changing the orientation of the irradiance pattern based on the orientation control signals; anda beam delivery and focusing subsystem for sequentially positioning and focusing the modified beam into at least one well-focused spot on each target to process the material of each target. 32. The system as claimed in claim 31, wherein the beam delivery and focusing subsystem sequentially positions and focuses the modified beam to a plurality of well-focused spots extending along a laser processing path wherein the aspect ratio and the orientation of each of the spots is based on the predetermined dimensions and target orientation. 33. The system as claimed in claim 32, wherein the laser processing path is a curvilinear path. 34. The system as claimed in claim 32, wherein each of the well-focused spots is an elongated spot having a major axis and wherein the major axis of at least one of the spots is aligned with the laser processing path. 35. The system as claimed in claim 32, wherein each of the well-focused spots is an elongated spot having a major axis and wherein the major axis of at least one of the well-focused spots is transverse the laser processing path. 36. The system as claimed in claim 31, wherein the first subsystem includes an ellipse generator and wherein the irradiance pattern of the modified beam is an elliptical irradiance pattern and the at least one well-focused spot is at least one well-focused elliptical spot. 37. The system as claimed in claim 36, wherein the second subsystem includes a beam rotator for rotating the modified beam. 38. The system as claimed in claim 31, wherein an aspect ratio and orientation of the at least one well-focused spot are controlled based on the predetermined dimensions and target orientation. 39. The system as claimed in claim 31, wherein the processing is micromachining. 40. The system as claimed in claim 31, wherein the processing includes semiconductor link removal, laser trimming, laser drilling or laser etching. 41. The system as claimed in claim 31, wherein the system compensates for system errors that would result in an out-of-round or an out-of-ellipse condition. 42. The system as claimed in claim 31, wherein the first subsystem includes a fixed expander/rotator based on an in-line or compensated offset optical path. 43. The system as claimed in claim 31, wherein the first subsystem includes a plurality of non-offset prism pairs. 44. The system as claimed in claim 31, wherein the first subsystem includes a multi-element, sphero-cylindrical expander. 45. The system as claimed in claim 31, further comprising a filter for filtering the laser beam to obtain an initially modified spot shape. 46. The system as claimed in claim 31, wherein the second subsystem includes an adaptive optical element. 47. The system as claimed in claim 31, wherein the first subsystem includes an adaptive optical element. 48. The system as claimed in claim 31 further comprising a filter for filtering the laser beam to obtain an initially modified spot irradiance profile. 49. The system as claimed in claim 31, wherein the beam delivery and focusing subsystem sequentially positions and focuses the modified beam into a well-focused spot that is scanned along a laser processing path wherein the aspect ratio and orientation of the spot is based on the predetermined dimension and target orientation. 50. The system as claimed in claim 31, wherein the irradiance pattern is an elliptical Gaussian beam. 51. The system as claimed in claim 31, wherein the irradiance pattern is a top hat in one direction and Gaussian in a direction orthogonal to the one direction. 52. The system as claimed in claim 31, wherein the first subsystem includes a first beam expander for shaping the laser beam to obtain an initially modified laser beam having a first elongated irradiance pattern with a first orientation. 53. The system as claimed in claim 52, wherein the first subsystem includes a second beam expander for further shaping the initially modified laser beam to obtain the modified beam having a second elongated irradiance pattern with a second orientation. 54. The system as claimed in claim 53, wherein the second subsystem includes at least one actuator for moving the anamorphic beam expander to control absolute orientation of the devices in response to the orientation control signals. 55. The system as claimed in claim 54, wherein one actuator moves one of the anamorphic beam expander to control relative orientation of the devices in response to the control signals.