Abstract: A projection optical apparatus for projection an image of an object onto a workpiece, which is suitable for use, for example, as an exposure apparatus used in the manufacture of integrated circuits. The projection optical apparatus includes an image forming optical system whose optical characteristic is changed by the light energy supplied from the illuminated object. A change of the optical characteristic of the optical system is determined by the use of a predetermined parameter whereby when the distribution of the light energy on the pupil of the optical system is changed, the parameter is correct in such a manner that the change of the optical characteristic determined by the parameter is changed in correspondence to the change in the distribution of the light energy.

Abstract: A Curie temperature (Tc) writing magnetooptical recording medium which uses a dual perpendicular magnetic layer is composed of a first layer having a low Curie point (TL) and a high coercive force (HH) and a second layer having a relatively high Curie point (TH) and low coercive force (HL) and wherein data is written by applying an external magnetic field to the medium which is heated to a temperature higher than the low Curie point (TL) and lower than the high Curie point (TH). The Tc writing magnetooptical recording medium is characterized in that both the first and second layers are made of an RE-Fe-Co amorphous alloy, wherein the RE represents at least one rare earth metal selected from the group consisting of Tb, Dy, Gd and Ho.

Abstract: A protective device for photographic masks or reticles used in the photolithographic operation for fabricating semiconductor devices. The protective device includes a frame having a protective pellicle attached thereover and the frame includes temporary fastening means for detachably fastening the frame to a mask substrate. The temporary fastening is effected by using for example vacuum chucking, magnetic attractive force or spring force. The frame may be formed with vent holes each having a filter so that the internal pressure of the space enclosed by the pellicle and the frame on the mask is made equal to the outside air pressure.

Abstract: Apparatus for measuring the distance to an object comprising projection means for projecting a radiation beam onto the object including a radiation generating means and a first optical system, and detection means for detecting the radiation beam reflected from the object including radiation detecting means having a radiation-receiving surface for detecting the intensity distribution of the radiation on said radiation-receiving surface and a second optical system for guiding at least a portion of the reflected radiation beam from the object to said radiation-receiving surface, an optically conjugated relation being held between said radiation-receiving surface and an area of the optical axis of the first optical system.

Abstract: A projection exposure apparatus includes illuminating means for applying energy rays to a mask having a predetermined pattern formed thereon, a projection optical system for forming the image of the pattern in a predetermined projected state on a responsive substrate, adjusting means for correcting the fluctuation of the projected state of the image caused by the passage of the energy rays, exposure control means for controlling the energy rays so that the pojected image of the pattern by the projection optical system is transferred onto the responsive substrate under a predetermined exposure condition, means for making information regarding the reflectivity of the responsive substrate, and main control means for controlling the adjusting means on the basis of the predetermined exposure condition of the exposure control means and the information regarding the reflectivity.

Abstract: A method for successive alignment of each of a plurality of chip patterns regularly arranged on a substrate to a reference position comprises moving the substrate so as to successively make selected chip patterns correspond to the reference position in accordance with design data representative of the positions of the selected chip patterns, measuring the positions of the selected chip patterns when made to correspond to the reference position, determining on the basis of the measured positions, coefficients of an operational equation so that the sum of the square of deviations between positions of the selected chip patterns determined by use of the operational equation and positions of the selected chip patterns represented by design data may be minimum, determining positions corresponding to the plurality of chip patterns on the basis of the operational equation, and moving the substrate in accordance with the determined positions.

Abstract: An apparatus for measuring the optical characteristics of a lens disposed in a measuring optical system illuminated by the beams of a plurality of light sources, the apparatus includes photoelectric detecting means having a detecting surface disposed substantially orthogonal to the optical axis of the measuring optical system for detecting the positions of the light beams passed through the lens and producing a photelectric signal, optical characteristic calculating means responsive to the signal to calculate the spherical power, the cylindrical power and the principal meridians axis degree of the lens, deviation detecting means responsive to the signal to detect the amount of deviation of the central position of the light beams passed through the lens from the position of the optic axis of the measuring optical system, eccentricity calculating means for calculating the eccentricity of the optic axis of the lens from the optic axis of the measuring optical system in a two-dimensional coordinates system on the

Abstract: The projection optical apparatus includes light-emitting means which are disposed on a stage movable along the image plane in the projection optical apparatus and which define a light-emitting plane having a predetermined shape; photoelectric detection means which is disposed at a position substantially in conjugate relationship with a pupil of said projection optical apparatus and which receives the light emitted from the light-emitting plane of the light-emitting means through the projection optical system and a mask in which a pattern is defined at a predetermined position; and position detection means which controls the stage in such a way that the image projected on the light-emitting plane is shifted in relation to the mask pattern and which detects the superposed position between the image and the pattern in response to the light signal derived from the photoelectric detection means while the projected image is shifted and to the position of the stage.

Abstract: A system for placing thereron an object to be inspected, scanning the surface of the object to be inspected by a light spot and inspecting a foreign substance on the basis of light information produced by the foreign substance on the surface of the object to be inspected includes light information producing means including a member for producing light information substantially similar to the light information produced by the foreign substance, and means for disposing the member on a surface substantially identical to the surface of the object to be inspected placed on the system.

Abstract: A visual display device in a video instrument capable of alternatively setting the frame mode and the field mode comprises display means having a display area, means for driving the display means by a first display mode in which a plurality of patterns are displayed while being distributed at a predetermined density in the display area and a second display mode in which a plurality of patterns are displayed while being distributed at a density lower than the predetermined density in the display area, and means for selecting the first display mode when the frame mode is set, and selecting the second display mode when the field mode is set.

Abstract: A Fresnel lens provided in the finder of a camera includes a central portion through which an optic axis passes, and a plurality of annular portions spaced apart from the central portion and disposed concentrically. The central portion and the plurality of annular portions have their respective focal lengths. The focal length of the central portion is shorter than the focal length of one of the annular portions which is remotest from the optic axis.

Abstract: In an automatic focusing apparatus, wherein first zone representing an in-focus condition and a second zone for sufficiently assuring detection precision of the automatic focusing apparatus are provided for the position of a focusing lens, the focusing lens is driven on the basis of a defocus amount when the defocus amount falls within the range between the first and second zones, and thereafter an in-focus signal is output upon driving of the focusing lens, thereby shortening a delay time from the end of driving of the photographing lens to generation of the in-focus signal.

Abstract: Apparatus for measuring curvature of an object automatically is so composed to guide two radiation beams reflected by the object to a linear image sensor, and determine the curvature of the object from the signals obtained from the linear image sensor, in response to the distance of two radiation beams on the sensor. The apparatus is further provided with an image rotator between means for generating two radiation beams and the object.

Abstract: A zoom lens has, in succession from the object side, a first lens group of positive refractive power, a second lens group of negative refractive power, a third lens group of positive refractive power and a fourth lens group of positive refractive power. The first lens group, the third lens group and the fourth lens group are movable toward the object side for a magnification change from the wide angle end to the telephoto end. The focusing up to a short distance object is made possible by moving the second lens group along the optic axis from the position of its telephoto end toward the object side and moving the third lens group along the optic axis from the position of its telephoto end. The zoom lens satisfies the following condition:-0.5<.chi.3/.chi.2<0.5,where .chi.2 is the amount of movement of the second lens group from the telephoto end toward the object side for short distance focusing and .chi.

Abstract: A stage device comprises an XY-stage movable two-dimensionally in a predetermined reference plane, a Z-stage provided on the XY-stage and capable of a vernier movement in a Z-direction substantially perpendicular to said reference plane, and a levelling stage provided on the Z-stage and capable of an arbitrary inclining movement with respect to the reference plane. There is also provided a laser interferometer for measuring the position of a stage base portion in the X- or Y-direction by projecting a light beam onto a mirror provided on the Z-stage, and the measuring axis of the interferometer is so selected as to be contained in the reference plane. The levelling stage can be inclined in an arbitrary direction with means for driving plural points of the levelling stage independently in the Z-direction. Further it is so designed that the moving points are approximately positioned on the reference plane when the driving points are in a predetermined neutral stage.

Abstract: An apparatus for detecting a position of a semiconductor wafer comprises a linear alignment mark formed on a surface of the wafer along a pair of parallel straight lines extending in a given direction intersecting a radial direction of the wafer. The alignment mark includes at least two projection sections projected from the surface and spaced from each other in the given direction. Each of the projection sections has a first stepped edge provided on or along one of the pairs of straight lines and a second stepped edge provided on and along the other of the pair of straight lines, the pair of straight lines being separated from each other by a distance d', and each of the projection sections being defined such that the following relationship is satisfied:l'>d'where l' is the length of one of the projection sections in the given direction.

Abstract: A projection lens for projecting an image onto a screen includes, in succession from the screen side, a first lens component having a positive refractive power, a second lens component having a positive refractive power and whose both lens surfaces are convex surfaces, a third lens component of meniscus shape having its convex surface facing the screen side, and a fourth lens component having a negative refractive power and whose surface which is adjacent to the screen is a concave surface.

Abstract: A zoom lens comprises, in the order from the object side, a first diverging group of lenses and a second convergent group of lenses. The first and second groups of lenses are movable along the optical axis to effect zooming. The first group comprises, in the order from the object side, a negative meniscus lens having its convex surface faced to the object side, a negative lens and a positive lens having its surface of larger curvature faced to the object side. The second group of lenses comprises, in the order from the object side, a positive lens, a positive lens formed by a single lens or a combination of cemented positive and negative lenses and functioning as an achromatic lens, a negative lens having its surface of larger curvature faced to the image side and a positive lens. The zoom lens satisfies certain conditions.

Abstract: An illumination optical system comprises a multi-beam generator which includes a plurality of each of two kinds of lens elements different in optical characteristics and which is interposed between a source for generating a collimated light beam and a light condenser. The multi-beam generator generates a large number of secondary light sources from the collimated light beam. The illumination optical system is capable of supplying illuminating light rays having an extremely uniform illumination distribution.

Abstract: A rear conversion lens to be mounted in between an objective lens and a determined image plane to produce a composite focal length longer than the focal length of the objective lens itself comprises, in the order from the object side a first lens component, a second lens component and a third lens component. The first lens component has a positive focal length and the image-side lens surface being convex toward the image side. The second lens component has a negative focal length and the object-side lens surface being convex toward the image side. The third lens component has a negative focal length and is in the shape of a meniscus convex toward the image side.