Abstract: A method for comparing first and second digital representations of an image, the method comprising the steps of: for each individual translation from among a plurality of translations from the first digital representation to the second digital representation: for each individual image location from among a plurality of image locations within a comparison entity within the first digital representation, determining a binary legitimacy value of the individual translation for the individual image location by comparing the individual image location to a location in the second digital representation defined by operating the individual translation on the individual image location; and combining the binary legitimacy values of image locations within the comparison entity, thereby to generate a comparison entity legitimacy value determining whether the individual translation is legitimate for the comparison entity; and announcing a defect for the comparison entity if none of the plurality of translations are legitimat

Abstract: This invention discloses an apparatus for optically inspecting an object having upper and lower faces for indicating the condition of the object, including a lighting system periodically reflecting a beam of light from one face of the object to produce a series of short-duration time-spaced reflected beams, and periodically transmitting a beam of light through both faces of the object to produce a series of short-duration time-spaced transmitted beams time-interlaced with the reflected beams, a sensor sensing the short-duration time-spaced reflected beams and transmitted beams, and generating electrical outputs corresponding thereto, and a processor receiving the electrical outputs and processing them to provide an indication of the condition of the object.A method of optically inspecting an object having upper and lower faces for indicating the condition of the object is also described.

Abstract: This invention discloses an universal chuck for holding plates, including a base having a longitudinal axis and a transverse axis, a lower carriage movable on the base along said longitudinal axis, an upper carriage movable on the lower carriage along the longitudinal axis, a plate mounting carried by the lower carriage at one side thereof for mounting one edge of a plate to be held by the universal chuck, and a plate mounting carried by the upper carriage at the side thereof opposite to the one side of the lower carriage, for mounting the opposite edge of the plate to be held by the universal chuck, such that moving the lower carriage and the upper carriage with respect to each other and with respect to the base along said longitudinal axis, changes the distance between the lower carriage and upper carriage plate mountings to thereby enable the chuck to hold plates of different longitudinal dimensions.

Abstract: A method and apparatus for inspecting the surface of articles, such as chips and wafers, for defects, includes a first phase of optically examining the complete surface of the article inspected by scanning its complete surface at a relatively high speed and with an optical beam of relatively small diameter, particularly a laser beam, and a second phase of optically examining with a relatively high spatial resolution only the suspected locations for the presence or absence of a defect therein.

Abstract: An inspection method including the steps of providing a patterned object to be inspected and compared with a reference, inspecting the patterned object and providing an output of information relating to the visual characteristics of the patterned object, comparing binary level information relating to the visual characteristics of the patterned object to binary level information relating to the visual characteristics of the reference, and comparing gray level information relating to the visual characteristics of the patterned object to gray level information relating to the visual characteristics of the reference.

Abstract: A method for comparing first and second digital representations of an image, the method comprising the steps of: for each individual translation from among a plurality of translations from the first digital representation to the second digital representation: for each individual image location from among a plurality of image locations within a comparison entity within the first digital representation, determining a binary legitimacy value of the individual translation for the individual image location by comparing the individual image location to a location in the second digital representation defined by operating the individual translation on the individual image location; and combining the binary legitimacy values of image locations within the comparison entity, thereby to generate a comparison entity legitimacy value determining whether the individual translation is legitimate for the comparison entity; and announcing a defect for the comparison entity if none of the plurality of translations are legitimat

Abstract: The present invention seeks to provide an improved system for inspection of and detection of defects in objects such as reticles, photomasks, semiconductor wafers, flat panel displays and other patterned objects. Preferably, the system has two or more stages, whereby the object is examined separately for fine defects, preferably by inspecting a binary level representation of the object, and for ultra fine defects, preferably by inspecting a gray level representation of the object. The system also preferably includes reinspection apparatus for reinspection of detected defects, thereby to reduce the false alarm rate, and for classifying the remaining defects by size, area and type.