Abstract: A laser system, which is used in material processing to produce a radiation line of small width and uniform high intensity in the longitudinal direction, produces radiation that has different mode numbers M2 perpendicular to the propagation direction.

Abstract: A laser system, which is used in material processing to produce a radiation line of small width and uniform high intensity in the longitudinal direction, produces radiation that has different mode numbers M2 perpendicular to the propagation direction.

Abstract: In a device and a method for homogenising laser radiation with a homogeniser, the relative position and/or direction between the laser radiation and the homogeniser or an effect of the homogeniser is measured in order to adjust the said relative position and/or direction as a function of the measurement signal.

Abstract: A method for operating an optical projection system including projection optics is disclosed. The projection optics project an image of the object on the substrate at an image distance from the projection optics. The image has a size dependent on the size of the object and the ratio of the image distance to the optical distance of the object from the projection optics. The image distance can change with changes in the condition of the projection optics such as changes in the temperature of elements of the projection optics. The image distance is monitored. If the image distance changes, the substrate is moved to the new image distance and the optical distance of the object is correspondingly changed such that the ratio of the image distance to the object distance stays the same.

Abstract: A device is obtained for converting the intensity distribution of a laser beam in particular into an intensity distribution which falls constantly along an axis from one side to the other in that a homogenizer (10), which mutually superimposes the sub-beams of the laser beam such that when a laser beam with a specific intensity distribution passes through the homogenizer, a homogenization of the intensity distribution of the laser beam is promoted, is combined with at least one inverter (24, 26) which inverts the intensity distribution of a sub-region, in particular a sub-beam or a plurality of adjacent sub-beams, along at least one axis along which the intensity is to be converted. The extent of the fall in intensity from one side to the other can be controlled by means of the number of the inverters.

Abstract: A device is obtained for converting the intensity distribution of a laser beam in particular into an intensity distribution which falls constantly along an axis from one side to the other in that a homogenizer (10), which mutually superimposes the sub-beams of the laser beam such that when a laser beam with a specific intensity distribution passes through the homogenizer, a homogenization of the intensity distribution of the laser beam is promoted, is combined with at least one inverter (24, 26) which inverts the intensity distribution of a sub-region, in particular a sub-beam or a plurality of adjacent sub-beams, along at least one axis along which the intensity is to be converted. The extent of the fall in intensity from one side to the other can be controlled by means of the number of the inverters.

Abstract: This invention concerns a process useful for increasing the accuracy of the shape of a laser ablated feature formed on a substrate, especially where the substrate is a polymeric article. The process includes irradiating the polymeric article with laser light that has passed through a retardation plate selected from stationary adjustable plates, rotating plates or spinning plates, preferable in multiples of quarter-waves or half-waves. This invention also concerns a laser apparatus useful for making ablated features in a substrate having a radiation source; a mask positioned between the radiation source and a substrate to be irradiated, and a retardation plate which is stationary and adjustable, rotating or spinning plates.

Abstract: An optical apparatus for the homogenization of laser radiation, in particular of an excimer laser, and for the generation of several lighting fields (F1, F2) from this radiation comprises a plurality of acentric lens segments (G1a, G1b, G1c, G1d; G2a, G2b, G2c, G2d). The acentric lens segments are characterized in that they are segments of cylindrical lenses with an axis of symmetry and that the portion of the cylindrical lens which contains the axis of symmetry is not part of the acentric lens segment. Several groups (G1, G2) of acentric cylindrical lens segments are provided, with each group generating a lighting field (F1, F2) of homogeneous energy density. A collecting lens (S) is arranged downstream of the acentric lens segments, which generates the lighting fields (F1, F2) on a work plane (E).

Abstract: An optical device is described for generating a sharp illuminating line on an illuminating plane from a high-power laser beam. The sharp illuminating line includes long and short axes. The optical device comprises an anamorphic setup of imaging and homogenizing optical systems for the separate imaging and homogenizing of the laser beam in the directions of the long and short axes. For imaging and homogenizing the laser beam in the direction of the short axes, a slit is illuminated homogeneously and the slit is imaged on the illumination plane by reducing optics.

Abstract: An optical device for homogenizing a light beam comprises a plurality of first lenses on which the light beam impinges from one side. At the side on which the light beam impinges the first lenses are convex, while they are prismatic at the opposite side at which the light beam emerges from the lenses. At least one convergent lens is disposed downstream of the lenses mentioned in the direction of the light beam. Instead of giving the first lenses a prismatic configuration it is also possible to make the first lenses plano-convex and arrange second lenses of plano-concave shape downstream of the first lenses in the direction of the light beam.

Abstract: For small line width tuning of a laser, especially a pulsed dye laser, a reference beam is uncoupled from the laser resonator (10,18) and directed to a beam position photosensor such as an adjacent pair of photo diodes. A control signal for synchronizing the movements of a grating (10) and an etalon (18) of the laser resonator is derived from a local change of the reference beam in order that synchronism may be achieved in the movement of both the etalon and the grating.