Abstract: An optical system of changeable magnification comprising a master lens arranged normally in axial alignment to an image receptor to be switchable to another light path which includes a rear converter, and a reflection mirror arranged so that when the master lens is switched from the first to the second light path, the light emerging from the converter is directed to the image receptor, while blocking the first light path off the image receptor, thereby the image magnification is changed from one value to another.

Abstract: A system for directing successive beam pulses of a pulsed laser into different optical fibers, for transmission therethrough, is disclosed. The system comprises at least one lens, a plurality of optical fibers with the tips thereof positioned proximate a focal point of the lens, and at least one galvanometer driven mirror for directing a laser beam through the lens for focusing separately onto each fiber tip. The galvanometer, driven by computer generated position addresses, moves the mirror, between laser pulses, to predetermined positions each effective to direct the laser beam, through the lens, into one of the fiber tips for transmission via the fiber to a remote workstation location. In a first illustrated embodiment, a single mirror is mounted to direct the laser beam into fiber tips positioned substantially in the same plane and proximate the focal points of eight lenses.

Abstract: A function-conversion device for a ground monocular telescope of an erecting-prism type ground monocular telescope. The device includes a rotational plate so mounted as to be horizontally movable in a vicinity of the focal plane of the objective lens of the telescope, with a plurality of windows being provided in the rotational plate and with a reticle and/or a visibility diphragm or a second objective lens being mounted in alignment with the windows. This arrangement provides a convenient and easy-to-handle function-conversion device since the windows can be selectively moved into the vicinity of the focal plane.

Abstract: In a telescope having primary and secondary reflectors, wherein the actual primary reflector surface deviates from an ideal primary reflector surface, such deviation is compensated for. At least one intermediate element forms an image of the primary surface onto the secondary surface, so each point on the secondary surface corresponds to a point on the primary surface. The secondary surface is formed with a deviation from an ideal secondary surface, with the "piston" distance of each point on the actual secondary surface equal to the piston distance of a corresponding point on the actual primary surface from the ideal primary surface. It is found that this results in electromagnetic (e.g., light) rays which strike a deviating area of the actual primary surface being brought to the same focus as if the actual primary surface did not have a deviation from an ideal primary surface.

Abstract: The load-locking joint, which is particularly suitable as a suspension mount for surgery microscopes, comprises a joint ball mounted in a housing and having a shaped-on hinge pin or rod, whose free mobility can be inhibited in its mount by mechanical clamping elements. The self-locking action is brought about in that the clamping elements engage on the spherical surface of the ball and during the rotation of the joint ball are carried along on said side, but are supported on a fixed abutment on the other side, the length between the point on the joint ball and the support point increasing with a slope, whose tangent is smaller than the friction coefficient.

Abstract: In order to substantially reduce the time required for examination and to enable the structure of the microscope apparatus for examining a wafer to be made in a compact size, the apparatus comprises a wafer examination unit provided midway on the transportation course of the wafer transporting means for being able to move the wafer under examination independently of the direction of its transporation, and an objective disposed above the wafer examination unit for being able to move along the upper face of the wafer which is held at the position of examination and in a direction different from the direction of the transportation.

Abstract: A changeover type variable magnification optical system whose focal length is changed by locating an auxiliary lens on the image side of a master lens assembly. The system satisfies following inequalities of:0.2<f.sub.2 /f.sub.1 <0.71where f.sub.1 and f.sub.2 are the effective focal lengths of the master lens assembly and the auxiliary lens, respectively. The auxiliary lens is constructed include of at least one aspherical lens surface.

Abstract: A drive with a D.C. motor is provided for the oscillating deflection of a mirror for the line by line scanning of pictures. It is supplied with alternating current so that the rotor executes a harmonic oscillation. To fix the zero position or the oscillation mean position, a magnet with an outwardly oriented magnetic pole is fixed to the mirror carrier. Another magnet is fixedly disposed on the housing thus that a reciprocal pole to the pole on the mirror carrier is opposite to it. Thus it is not necessary to overcome a force increasing proportionally to the deflection which also would interfere with the oscillation, as in the known zero position by means of a torsion bar.

Abstract: A night vision viewing system, suitable for mounting on an observer's headgear (11), wherein light rays from a forward scene pass to the observer's eye (E) via a path comprising a forward looking objective lens (23), an inclined reflector (35) which directs the rays passing through the objective onto an outwardly sideways looking input face of an image intensifier (31), and a fibre optic stub (33) which directs rays from the output face of the intensifier onto a second reflector (27) which directs the rays downwardly into an eyepiece (21) which is in the observer's forward line of sight. The eyepiece incorporates an internal surface (37) having both light reflective and light transmissive properties which directs rays entering the eyepiece from the intensifier to the observer's eye. The fibre optic stub serves to effect rotation of the intensified image to present an intensified image of correct orientation to the observer.

Abstract: Method of designing a compact binocular night vision instrument with an electronic image intensifier (2) which is oriented so that its symmetry axis forms a right angle with the line of sight (19) between the night vision binocular and the scene to be observed. The total forward length thereby becomes particularly short, thus reducing the downward torque which is troublesome when the night vision binocular is carried like a pair of spectacles, attached to the head (generally called night vision goggles). The total forward length may be even further reduced if the symmetry axis of the objective lens (1) is also at right angles with the line of sight (19). These measures makes feasible a simple beam splitter system where the optical axis through one of the eye pieces (13B) intersects the common optical axis beam splitter (14), and to design an instrument enclosed in a single housing having a smooth exterior shape which is easy to grasp.

Abstract: A stereomicroscopic inspection system having low eyestrain features is disclosed. The system (10) includes an objective lens assembly (12) for forming an image of a viewed object (22). A prism mechanism (14) is positioned adjacent to the objective lens assembly (12) for orienting the image along a heads-up axis. A telephoto objective assembly (16) is positioned adjacent to the prism mechanism (16) for focusing the image transmitted through the prism mechanism (14). A reticle (18) is positioned adjacent to the telephoto objective assembly, and the image is focused (16) onto the reticle (18). An assembly (20) is positioned adjacent to the reticle (18) for enabling heads-up viewing of the object by the viewer, (22) said system projecting a virtual image at a predetermined distance from the viewer. This distance may be substantially equal to the eye's natural focusing distance to minimize eyestrain.

Abstract: An improved lens system for a projection television is described. The lens system is designed to be used with a cathode ray tube having a face glass with an aspheric surface having phosphor elements mounted thereto. The aspheric surface of the face glass has its maximum radius at the optical axis and is of lesser radius outwardly thereof. From the screen, the lens system companies a first aspheric lens of relatively weak power, a second biconvex lens of relatively high positive power, a third aspheric lens of weak positive power and a fourth lens having a concave face on its screen sider and of relatively large negative power.

Abstract: An illumination optical system for an endoscope comprising an illumination lens, which is provided on the object side of the light exiting end of a light projecting element and comprises at least one aspherical lens element, the illumination optical system for an endoscope being arranged to be applicable to a wide angle endoscope and, at the same time, being arranged to have a favorable light distribution characteristic, which ensures bright illumination up to the marginal portion of the field, and arranged that the loss in the intensity of light is small.

Abstract: A lens barrel for a zoom lens in which zooming is achieved by moving both front and rear lenses but focussing is achieved by moving only the front lens. When a sliding ring slides linearly for zooming, a cam sleeve is rotated. A pin in the cam sleeve engages a cam groove in a moving frame for the front lens to thereby linearly move the front lens. Another cam groove in the cam sleeve engages a pin in the frame for the rear lens to thereby also linearly move it. Focussing is achieved by a threaded rotation of the frame for the front lens on the moving frame.

Abstract: A machine and process is provided for automatically removing babbitts from flaker knives and the like, molding new babbitts onto the knives and trimming the new babbitts to precise dimensions. The machien has a frame on which is mounted a magazine for storing the knives and a movable transfer plate transfers a knife from the magazine to successive positions for removing the babbitts, forming new babbitts and trimming the new babbitts. The babbitts are removed by a power actuated punch engaging the babbitts while the knife is held in the appropriate position.

Abstract: A partially color corrected projection lens having three groups comprising from the image end a first group serving to correct aberrations, a second group supplying essentially all of the positive power of the lens and a third negative group where the second group comprises two positive elements with a negative element therebetween.

Abstract: A telephoto zoom lens system comprising a first lens group having positive refractive power, a second lens group having negative refractive power, and a third lens group comprising a front subgroup, which has positive refractive power, and a rear subgroup, the telephoto zoom lens system being arranged that the focal length thereof is varied by moving the first, second and third lens groups along the optical axis in the state that the varifocal functions is alloted to the second and third lens groups so that the magnifications of both of them increase at that time, the telephoto zoom lens system being thereby arranged to be small in size, high-performanced and low cost.

Abstract: A light beam fluctuation compensating device is provided which comprises a light source, a first optical system for splitting a light beam emitted from said light source into two light beams and a second optical system for irradiating the two light beams split by said first optical system onto a target. A light beam fluctuation method utilizing the device is also provided.

Abstract: A zoom finder comprising a system for forming the image of a measuring field frame and a vari-focal system in the order from the object side and arranged that the apparent size of the measuring field frame varies at the time of zooming.

Abstract: A selective shading device has a number of shading plates or planar members and a supporting body that holds the plates or planar members in such a manner that they are arrranged radially with respect to an optical axis. The device blocks sagittal bundles of rays. A preferred example of the supporting body is a cylindrical frame that holds the shading plates perpendicularly to the inner surface thereof. Alternatively, the shading planar members are formed within a lens element along the edge thereof.