Abstract: The invention concerns a device for correcting the shape of an object by laser treatment.The device comprises means (1) for emitting a laser beam (FL) and means (2) for generating a treatment laser beam (FLT) comprising at least one lobe of elongate cross-section. Means (3) enable focussing of the image of the lobe or lobes of the treatment laser beam on the area of the object (OE) to be corrected and means (4) enable displacement of the image of the lobe of the treatment laser beam in translation or in rotation over the area of the object to be corrected. The total correction or ablation is effected by the summation of a plurality of elementary discrete ablations.Application to refractive surgery in the case of keratomileusis for myopia, hypermetropia or astigmatism, and to shaping contact lenses and intra-ocular implants.

Abstract: An object of the present invention is to provide an optical system for lithography wherein the zero order component of the main lithographic image is unobstructed and the zero order component in the ghost image is removed. The optical system includes a beamsplitter component and a condensor lens structure for illuminating a lithographic mask from a range of directions which excludes a range of directions that are sufficiently close to the axis to add undesired background to the exposure field after multiple reflections with the lens. The optical system further includes an excimer laser and a lens system having an array of stops for intercepting multiple images of the excimer laser after they reflect from the primary wafer image or other surfaces such as the mask or lens surfaces.The illuminating zero-order beams reflect obliquely off the wafer after contributing to the image, where they are then refocussed to the opposite side of the pupil (the primary mirror).

Abstract: This is a static photometric polarimeter for use with a sample S upon which a beam passed through a beam splitter (which reflects the beam to a detector D.sub.o) and which beam is 45.degree. polarized. The reflection of the beam from the surface of sample S is passed to a polarizing beam splitter with one portion of the reflected beam going to a detector D.sub.s which measures the perpendicular polarization component of the beam and the other portion of the beam going to the detector D.sub.p which measures the parallel polarized portion of the reflected beam.