Abstract: Method for optically measuring submicron dimensions of an object or covering between two objects, and device implementing such method, wherein a light beam (23) is emitted by means of an arc lamp (22) into a system (21) with an optical monofibre (8) having a diameter larger than 500 .mu.m and a length longer than 3 m, the beam (23) is focussed to the object to be measured through the lens (32) of a microscope, the reflected beam passing through the microscope lens is separated from the incident beam in order to direct it towards the sensors of the matrix cameras (41, 42) of the charge coupling type and the spatial signals thus obtained are processed in order to reconstitute the contours of the object or to measure the covering between the two objects.

Abstract: Optical system for the automatic alignment of two motifs in which the alignment marks of a first fixed motif forming the reference are constituted by at least one pair of identical periodic optical gratings with a constant spacing P and having a predetermined distance d.sub.X from one another such that the equation d.sub.X =(n+.epsilon.) P is proved, n being an integer and .epsilon. a fraction of unity.An optical modulator, for example electro-optical means incorporating a Pockels cell alternately illuminate with the timing of the high frequency control signals, the said gratings in windows, whose position can be regulated in accordance with a given axis. The image of these windows is projected onto gratings carried on a second moving support to be aligned and produces orders of diffraction. An optoelectronic detector detects a predetermined order of diffraction. The high frequency-modulated output signals are transmitted to control circuits for producing the automatic alignment.

Abstract: Arc lamp illuminator which can be used in an optical device for the transfer of patterns, incorporating a mixed fibre bundle which intercepts in an image plane of the source part of the emitted radiation. The exit cross-section of the bundle is adapted to the degree of coherence of the desired illumination measured on the pupil of the optical transfer device. At the entrance, the fibres of the bundle are assembled into two separate bundles, whose ends are aligned with the maximum intensity zone formed in the image plane of the source.

Abstract: An illuminator for supplying a divergent illuminating beam from an area of predetermined energy distribution and dimensions comprising a coherent source whose image is formed in a plane by imaging means incorporating electrically controlled optical scanning means making it possible to displace the image in the said area in accordance with a predetermined law.

Abstract: A compact optical coupling device particularly adapted for coupling between a source and two optical fiber ends having a function of separation of the radiation from the source between these two ends. The device comprises a small-size separator cube, a plano-convex microlens whose flat face is bonded to the input face of the separator cube, and two square-section end-pieces bonded to the two output faces of the separator cube, each enclosing one fiber end.

Abstract: An optical system for aligning two patterns particularly by photo-repetition in which a first pattern formed by two optical networks, disposed along two coordinate axes is illuminated by the image of a second pattern comprising two optical networks, forming a reference produced from the orders of diffraction. In a variation, the optical networks are formed from a series of parallel strokes whose thickness and spatial distribution in a first direction parallel to one of the coordinate axes are determined by a pseudo-random code; the strokes of the optical networks of the first pattern being furthermore interrupted periodically in a second direction orthogonal to the first direction so as to form an optical network with a constant pitch in this direction. The optical alignment system comprises means for detecting the intensity of a predetermined part of the orders of diffraction in the second direction.

Abstract: Illuminating device comprising a laser source providing a coherent beam with gaussian distribution of intensity and means for separating the initial beam into four parts along two orthogonal directions, means for recombining the four parts resulting in their partial superimposition in a predetermined plane and means for averaging the interferences produced in the plane by the four parts.

Abstract: An optical system for aligning two patterns in which the alignment takes place in two phases. In the first phase, the first pattern is aligned with respect to a third fixed intermediate pattern, forming a reference, and during the second phase the second pattern is aligned with respect to this third pattern. The first pattern is formed by a pair of alignment reference marks and the third pattern comprises a first pair of complementary reference marks. The second pattern is also formed by a pair of alignment reference marks and the third pattern comprises a second pair of complementary reference marks. In a preferred embodiment, these latter reference marks are formed by optical networks. The projection of one network on the complementary network produces orders of diffraction which are detected by opto-electronic means.

Abstract: The present patent application discloses an optical fiber interferometric rate gyro using the SAGNAC effect particularly adapted to the measurement of low rotational speeds comprising, between the radiation splitting and recombining device which directs two waves simultaneously towards the two ends of a single mode wound optical fiber and recombines the two waves emerging from the fiber after travelling in opposite directions at each of the two ends of the fiber, a splitter associated with a detector picking up a fraction of the wave emerging from the corresponding end, the speed measurement being obtained from signals from these detectors and from the signal from a detector picking up the radiation resulting from the recombination of both waves.

Abstract: An optical system for projecting patterns in order to reproduce the image of at least one modulating object on a mask or semiconductor wafer coated with photosensitive material for the fabrication of semiconductor components. In this system, optical reflecting means comprising one or a number of plane mirrors including at least one movable mirror are introduced in the optical path of the imaging objective. By forming additional optical paths, it is thus possible to associate with a photorepetition function different functions such as photocomposition or other photorepetition paths, or else to associate a device for ensuring alignment of the object-image planes and comprising optoelectronic detection means.

Abstract: In order to position a sensitized plate in the image plane of a projection lens, the optical projection system is provided with a set of extensible jacks placed in a circle around the lens, the desired image plane being defined by the ends of the jacks when they are in the outwardly displaced position. The plate can then be placed against the ends of the jacks by means of a spherical-bearing unit which is locked in position, whereupon the jacks are caused to withdraw and the plate can be displaced in the image plane while remaining at the focusing distance. The invention is well suited to the construction of photorepeaters.

Abstract: The present invention relates to the precise positioning of a body exhibiting a flat face, said latter requiring to be aligned, or in other words brought into coincidence with a mechanically indexed reference plane. The loading device in accordance with the invention comprises a levelling stage associated with a loading flap which can pivot about an axis. The stage comprises a base containing a cylindrical bore, and a lockable supporting stand equipped with a spherical-walled sleeve located in said cylindrical bore. The flap and the stage are equipped with mechanical indexing means which cooperate with those defining the reference plane.

Abstract: A system for testing a pattern recorded on a plate with a high density in relation to a reference pattern, comprising means for analyzing the pattern with a line detector and a logic circuit for processing the data supplied by the detector and data relating to the reference pattern, the two patterns being described line-by-line. The logic circuit is intended to detect the errors while admitting for each line a shift between the two patterns of one unit in a direction X or in a direction Y perpendicular to X, the maximum shift allowed for the entire pattern amounting, for example, to three units in each direction.

Abstract: The method consists in recording at least one reference mark on each of the patterns corresponding to the various levels of the circuit at a fixed point, in recording the reference mark of the first pattern in the semiconductor plate at the same time as the first pattern and then, after each positioning of the thin plate after the chemical treatments, in centering, by displacing the thin plate relative to the pattern, the images in the plane of the following pattern of at least two reference marks situated in the different zones with the complementary reference mark carried by the following pattern to be projected, the thin plate then being aligned with the following pattern to be projected.

Abstract: The invention relates to the positioning of an object comprising at least two fixed reference marks in an optical projection system. The system according to the invention comprises two projector arms illuminating two regions of the surface of the object through two marks, which form a reference system, having a variable inter-axis interval, display means enabling coincidence between the reference marks of the object and the reference system to be established.

Abstract: A mask photorepeater apparatus for the production of small size masks has an objective-holder whose lens has a magnification very much less than 1 and an object-holder able to move in a plane. For each printing operation, under the action of servomechanisms, the objective-holder rises or drops to bring its object plane within the plane of the object to be printed.

Abstract: The system according to the invention comprises means for displacing the lens and the object enabling magnification and focusing to be adjusted in dependence upon the lens used and co-operating with servocontrol means for the position of the lens which provide for automatic focusing while keeping magnification constant.