Abstract: A variable focal length lens system comprising a first lens unit which comprises a negative meniscus lens and a positive lens, a second lens unit which comprises a negative lens, and a third lens unit which comprises at least three lenses including at least one negative lens, the variable focal length lens system being arranged to vary the focal length by moving the second lens unit and arranged to have a large aperture ratio and high vari-focal ratio and to be small in size.

Abstract: A zoom lens comprising, from front to rear, a first lens unit of negative power, a second lens unit of positive power and a third lens unit, the first and second lens units being axially movable for zooming, and the zoom lens satisfying the following conditions:1.2f.sub.W <.vertline.f.sub.1 .vertline.<1.6f.sub.W0.9f.sub.W <f.sub.2 <1.3f.sub.W-0.35/f.sub.T <1/f.sub.3 <0.3/f.sub.T0.85f.sub.W <l.sub.1W <1.2f.sub.W0<l.sub.2W /f.sub.W <0.30<l.sub.1T /f.sub.W <0.20.7<(l.sub.2T -l.sub.2W)/f.sub.W <1.21.2<.vertline..beta..sub.2T .vertline.<1.1.sqroot.f.sub.T /f.sub.Wwhere F.sub.1, f.sub.2 and f.sub.3 are the focal lengths of the first, second and third lens units respectively, l.sub.1W and l.sub.2W are the first and second separations between the first and second lens units and between the second and third lens units respectively when in the wide angle end, l.sub.1T and l.sub.2T are the first and second separations when in the telephoto end, .beta..sub.

Abstract: The present invention provides a gradient refractive index type anamorphic planar microlens which can be utilized for collimating an elliptical beam radiated from a semiconductor laser, or the like, and a method of producing such a lens. To collimate light rays, in which astigmatism exists, it is necessary to use a lens in which the respective focal distances in the directions perpendicular to an optical axis are different from each other. It includes a semiellipsoidal refractive index distribution region formed in a transparent substrate so as to have a major axis and a minor axis on a surface of the transparent substrate.

Abstract: In a scanning optical system for deflecting a laser beam by a deflector to converge it on a scanning surface by a focusing lens, it is difficult to compensate for both an image surface curvature and a distortion aberration in the optical system. An optical system according to the present invention is designed to minimize a curvature of a meridional image surface of a focusing lens, and a sagittal image surface and distortion are compensated for by arranging an aspherical surface between the focusing lens and the scanning surface. This aspherical surface is advantageously arranged by forming a cylindrical lens, which is inserted to compensate for a tilting of the deflected surface, into an aspherical surface.

Abstract: A Tandem Scanning Microscope is disclosed using a modified Nipkow disk design. With this scanning system, scanning is performed using many apertures at once and using one disk for both image and illumination scanning. The apertures in the disk are in an annular pattern of spiral arms. Each aperture is located along a spiral arm at the end of a radius vector. Relative aperture locations are established in accordance with a mathematical relationship.

Abstract: A retroreflective sheeting has microretroreflective formations on one surface which are partially metallized and partially exposed to the atmosphere about them. It is produced by forming a coating on microprism surface, and this coating includes a thin metallic deposit over substantially the entire surface and a second coating material over only a portion of the surface. The coated surface is then exposed to a solvent to remove the coating from its predominant area and leave the metal deposit on only a minor portion of the area. A backing sheet is then applied over the microprisms and bonded to the retroreflective sheeting so as to leave an air interface about the predominant area of the microprisms. As a result, some light rays are retroreflected by the metal deposit and some are retroreflected by the atmosphere interface. The sheeting exhibits daytime whiteness over the bulk of its surface area.

Abstract: A wide angle projection lens which comprises from the image end a first lens unit of negative power having at least one aspheric surface, a second positive lens unit comprising at least two elements and a third negative element having an aspheric concave to the image, where the first lens unit provides negative power to the overall lens and serves as an aberration corrector including some field curvature.

Abstract: The microscope drape includes a one-piece seamless, substantially tubular main body portion. One or more separately formed sleeve-like extensions are joined to the main body portion with a reinforcing member provided at the joint. The reinforcing member is annular and defines a predetermined stress path to permit the drape to withstand a predetermined level of stress at the joint between the main body portion and the sleeve-like extension, and direct stress at the joint along the predetermined stress path. Thus, tension stresses imposed on a drape and the sleeve-like extension are distributed along a uniform stress path defined by the reinforcement member to help ensure against any rips or ruptures in this area when the drape is secured around the microscope.

Abstract: An integrated head-up and panel display system for aircraft cockpits and the like is disclosed. The system utilizes a wavelength-sensitive fold mirror to separate the HUD image and the panel images. The system includes a monochromatic HUD image source for projecting the HUD image toward the fold mirror, and at least one panel display image source for projecting panel imagery toward the fold mirror. The transmission function of the fold mirror is notched at the wavelength of the monochromatic HUD image source. Thus, the fold mirror reflects the HUD image in the direction of the HUD optical combiner which reflects the HUD image to the system exit pupil. The fold mirror is adapted to transmit light in the visible spectra outside the narrow bandwidth of the HUD image source, so that the panel image is transmitted through the fold mirror to a look-down display screen assembly.

Abstract: Plural overlapped Gaussian-shaped solid state semiconductor laser beams are focused onto the recording medium surface of a printer and will not optically interfere and cause any nonuniformity in printing due to optical interference because the respective laser beams are sequenced in ON/OFF operation so that relative to two or more overlapping laser beam spots focused to a recording medium surface, only one laser beam will be ON at any given time.

Abstract: An apparatus for increasing visual acuity while viewing an image comprising a roof prism having an apex with apex faces adjacent thereto, an eye piece lens mounted to a first apex face of the roof prism, and an objective lens mounted to a second apex face of the roof prism and to the lens of a pair of eyeglasses. The objective lens is mounted to the eyeglasses lens at a point such that the eye of a patient wearing the eyeglasses must be rotated at a angle of from about 25.degree. to about 50.degree. relative to the visual axis of the patient's eye when looking straight ahead to view an image through the apparatus.

Abstract: A projection apparatus comprises a light source, a light scanning optical system including an electro-mechanical transducer element having at least one mirror row comprising a plurality of movable mirrors capable of deflecting the light beam from the light source in at least two directions and arranged in a direction corresponding to the main scan direction, a driving device for putting out a signal for driving the movable mirrors, the movable mirrors deflecting the light beam in response to the signal, and a light-receiving member by which the light applied from the light scanning optical system is subsidiary-scanned, at least one of the shape and arrangement of the mirrors and the subsidiary scan pitch being set so that light dots adjacent to each other in at least one of the main scan direction and the subsidiary scan direction in the pattern of light dots formed on the light-receiving member by the deflected light from the movable mirrors of the mirror row overlap each other to a sufficient degree to obta

Abstract: A constant deviation beam scanning apparatus having a rotatable beam deflector with at least one reflective surface thereof lying in a plane that intersects the axis of rotation at an acute angle. One embodiment utilizes a rotatable, truncated, n-sided pyramidal mirror with at least one planar reflective scanning segment located on one of the n-sides of the pyramidal mirror. The pyramidal mirror's truncation surface lies in a plane normal to the mirror's rotation axis and contains at least one planar reflective segment. A constant deviation reflector having two reflective surfaces is positioned so that a collimated beam of light reflected by the truncation surface reflective segment is reflected by one of the constant deviation reflective surfaces to the other reflective surface and then to the at least one planar reflective scanning segment of the pyramidal mirror.

Abstract: A lens barrel includes a hollow rotary ring rotatable about the optic axis which is disposed within the hollow of a hollow fixed cylinder with a bearing interposed therebetween, a moving cylinder movable in response to rotation of the rotary ring which is disposed within the hollow of the rotary ring, a vibration wave motor which is disposed between the diametrical directions of the fixed cylinder and the rotary ring, and a rotor which is substantially secured to the rotary ring.

Abstract: A method and apparatus for rotating one or more mirrors in a beam scanning system includes a drive motor, a drive spindle, operatively connected to the drive motor, for rotation by the motor, a spindle support arrangement, and a mirror support wheel mounted on the spindle for rotation therewith. The spindle support arrangement includes a generally cylindrical spindle housing and a bearing mounted within the housing a predetermined distance from an open end thereof. The spindle extends through the spindle housing and the bearing and out of the open end of the spindle housing. The mirror support wheel defines a generally annular counter bore for receiving the open end of the spindle housing thereinto.

Abstract: An improved laboratory slide and related methods of manufacture and use, wherein the slide is designed for analysis and/or testing of liquid specimens and the like. The improved slide comprises a transparent upper coverslip affixed to a lower slide plate by a thin bonding agent of controlled thickness which may be a substantially monocellular thickness on the order of about 0.001 inch or less. In some forms, the bonding agent is shaped in cooperation with the slide plate and coverslip to define one or more examination chambers into which liquid specimens may be drawn by capillary action for viewing and analysis. In other forms, the bonding agent defines one or more elongated flow channels through which a specimen may be drawn, wherein the flow channels may be of varying height and/or include selected reagents along their lengths to perform selected testing of biological specimens and the like.

Abstract: Metrology for a microlithographic objective reducing lens 10 is integrated into a metrology block 20 secured to a lower region of the barrel 15 for lens 10. Block 20 has a central opening 27 around a lowermost element 11 of lens 10; and block 20 mounts distance detectors 28 around central opening 27, a pair of microscope objectives 30 and 31, and a pair of X and Y mirrors 40 and 41.

Abstract: A retroreflector is formed of a graded index lens with a reflective coating at one end. The lens has a length of an odd multiple of a quarter period thereof. Hexagonally shaped graded index lenses may be closely packed in an array to form a retroreflecting surface.

Abstract: An ultra-wide angle f-.theta. lens system comprising, in the order from the light beam deflector side, a first lens component having positive power, a second lens component having negative power, and a third lens component having positive power, the ultra-wide angle f-.theta. lens system being arranged to have an ultra-wide scanning angle widened to .+-.45.degree. and exhibiting an imaging performance of laser beam waist close to the diffraction limit in spite of the fact that the f-.theta. lens system comprises a small number of lenses.

Abstract: In a triplet type objective for a compact lens shutter camera with a diaphragm arranged behind the lens system, the first lens element is formed of glass and the second and third lens elements are formed of plastic, so that it is advantageous in manufacturing cost and weight. Furthermore, sufficient marginal light rays and flatness of the image field can be obtained.