Abstract: An image blur compensating telephotographic lens has four lens groups. The four lens groups comprise a first lens group having a positive power, a second lens group having a negative power, a third lens group having a positive power, and a fourth lens group having a negative power arranged in this order from an object side. In one embodiment, the telephotographic lens has a lens moving mechanism for moving the second lens group in a direction vertical to the optical axis in order to compensate for an image blur when a photograph is taken. In another embodiment, the telephotographic lens has a lens moving mechanism for moving the third lens group in a direction vertical to the optical axis in order to compensate for an image blur when a photograph is taken.

Abstract: An objective lens system for use with wavelengths in the visible spectrum, has first and second lens groups. The first lens group has one aplanat lens. The second lens group is a doublet. The second lens group is designed to correct for chromatic aberrations introduced by the first lens group. The power of the second lens group is inversely related to the index of refraction of the first lens group and the optical glasses of the lenses of the second lens group are selected to satisfy a novel color correction equation.

Abstract: A behind stop wide angle lens system comprises a negative meniscus lens L.sub.1 having a convex surface directed to the object, a positive meniscus lens L.sub.2 having a convex surface directed to the object, a double-side-concave negative lens L.sub.3 having both surfaces concaved, a double-side-convex positive lens L.sub.4 having both surfaces convexed, and a stop S. These lenses are arranged in the mentioned order from the end adjacent the object. The lenses satisfying the following conditions (1) to (4):-2.8f<f1<-1.3f (1)0.7f<f2<0.82f (2)1.5<r1/r2<2.3 (3)0.13<r3/r4<0.4 (4)wherein f represents the focal distance of the whole lens system, f1 represents the focal distance of the negative meniscus lens L.sub.1, f2 represents the focal distance of the positive meniscus lens L.sub.2, r1 and r2 respectively represent the radii of curvature of the object-side surface and the image-side surface of the negative meniscus lens L.sub.

Abstract: A steering mirror assembly operates in a stable manner with a high bandwidth, with one to two degree peak-to-peak angular stroke. The steering mirror assembly includes a mirror for directing signals to their destination by reflection. The steering mirror may be moved through any position in a cone of several degrees. Movement of the mirror is achieved by a number of actuators. The mirror is coupled to a flexure ring that locks out undesirable directions of motion. The mirror assembly also includes position sensor that indicate to the assembly where the mirror is currently positioned. Data from these sensors is used as feedback to appropriately adjust mirror position.

Abstract: A zoom lens system comprising a front lens unit which is composed of a positive meniscus lens component having a convex surface on the object side, a negative lens component and at least one positive lens component, and has a positive refractive power as a whole, and a rear lens unit which is composed of a positive lens component, a biconcave lens component and a negative meniscus lens component having a convex surface on the image side, and has a negative refractive power as a whole; and adapted so as to perform variation of focal length by varying the airspace reserved between said front lens unit and said rear lens unit.

Abstract: A mount for an optical element is disclosed in which an optical element can be adjusted to a plurality of positions to change the position of an output beam. In order to provide a mount which can be adjusted to precisely position the output beam in orthogonal directions, the optical element is mounted in a holder which is rotatable about a first axis, and the holder is mounted on a support which is rotatable about a second axis. When the optical element is rotated about the first axis, the output beam is adjusted along an arc in an X direction; and when the support with the holder thereon is rotated about the second axis, the output beam is adjusted along an arc in a Y direction.

Abstract: A zoom lens is disclosed comprising, in the order from the object side, a first lens unit having a positive refractive power, a second lens unit having a negative refractive power, a stop and a third lens unit having a positive refractive power, zooming being performed by moving the second lens unit along an optical axis and focusing being performed by moving the third lens unit, the zoom lens satisfying the following conditions;-0.6<.beta..sub.3T <-0.350.124<D.sub.T /f.sub.T <0.211where .beta..sub.3T is the image magnification of the third lens unit for an infinitely distant object in the telephoto end, D.sub.T is the separation between the stop and the third lens unit in the telephoto end and f.sub.T is the focal length of the entire lens system in the telephoto end.

Abstract: An apochromatic lens system is corrected for chromatic aberration at three wavelengths. The apochromatic lens system includes a plane glass and a plane lens which are interchangeable with each other. When the plane glass is disposed on the optical axis of the lens system, the plane glass cooperates with the lens system to correct for chromatic aberration at first and second wavelengths. When the plane lens is disposed on the optical axis instead of the plane glass, the plane lens cooperates with the lens system to correct for chromatic aberration at the first wavelength and at a third wavelength.

Abstract: A projection lens for projecting images displayed on an image display device having angle-of-view dependency has high image focusing characteristics corresponding to high definition images, wide field angle, and telecentric characteristics. In addition, a projection television system using the same can be minimized in its size.

Abstract: A glare reduction system for video display screens having a top, a bottom and two side projection panels wherein each panel projects outwardly from an edge of the video display screen. There is also included at least one shutter panel which is mounted at or near an outward edge of at least one of the projection panels and which is adjustable to control reflective light.

Abstract: A nearly index matched (NIM) optic is formed from at least two elements having indices of refraction that are substantially the same over a given range of wavelengths. The optical cell can have matched solid and fluid lenses in which the solid has at least one curved interface in contact with the fluid. The solid and fluid share a boundary with equal but opposite curvature at each point over the aperture of the NIM optic. The effective optical curvature of the boundary is reduced by the difference in the index of refraction between the two elements of the NIM optic. This difference in the index of refraction can be controlled by changing the index of refraction of at least one of the elements so as to change the difference in the index of refraction across the optical boundary.

Abstract: An optical system of a NX reduction catadioptric relay lens having sub-half micron resolution over the utlraviolet band width is described. A spherical mirror with a stop at the mirror is used to work at substantially the desired reduction ratio and the desired high numerical aperture sufficient to provide the desired high resolution. A beam splitting cube with appropriate coatings is used to form an accessible image of an object on an image plane. Refracting correctors in the path of the slow beam incident on the mirror and in the path of the fast beam reflected on the mirror are designed to fix the aberrations of the image formed by the mirror.

Abstract: A zoom lens of simple structure is disclosed comprising, from front to rear, a first lens unit of positive refractive power, a second lens unit of positive refractive power and a third lens unit of negative refractive refractive power, wherein these three lens units each are constructed from a single block, and zooming from the wide-angle end to the telephoto end is performed by moving the first and third lens units axially toward the object side independent of each other.

Abstract: A diffraction limited, f/6.0, 71.0 mm focal length telecentric scan lens which is color-corrected for 780 nm, 830 nm and 890 nm wavelengths. The lens includes, in succession from a side of incident light:a first negative meniscus lens element, concave toward the incident light side;a second positive meniscus lens element, concave toward the incident light side;a first plano-convex lens element, convex away from the incident light side;a second plano-convex lens element, convex toward the incident light side;a first cemented doublet including bi-concave and plano-convex lens elements, the cemented surface convex toward the incident light side; anda second cemented doublet including plano-concave and plano-convex lens elements, the cemented surface convex toward the incident light side.

Abstract: A stereoscopic full resolution image is displayed on a monitor which is perceived to be substantially flicker free. A left and right eye image of the object are digitally represented. The digitized images are divided into a plurality of horizontal raster lines comprised of a plurality of pixels. The odd and even lines of each image are separated and the result stored in four different locations. The four locations are repeatedly scanned at a 30 Hz rate and the monitor's display is refreshed four times for each scan. The sequential scanning alternates between left and right eye images and odd and even lines which are interleaved on the monitor viewing surface.

Abstract: A multifocal lens useful as a contact lens or implantable as an intraocular lens which comprises at least 3 zones, the first zone comprising a polymer of a specified refractive index, the second zone comprising a polymer having the same repeating units as the polymer comprising the first zone and having a specified refractive index differing from the refractive index of the polymer comprising the first zone by not more than 0.1 units and by not less than 0.01 units and the third zone between the first and second zones comprising a polymer having the same repeating units as the polymers comprising the first and second zones and having a refractive index continuously variable between that of the polymer comprising the first zone and that of the polymer comprising the second zone, the at least three zones being transparent and having no discontinuities visible to the human eye between the zones.

Abstract: A door-mounted security peephole providing an undistorted view over a relatively large area by use of a beam splitter optical system. The peephole comprises a door-mounted housing containing a beam splitter and light source arranged so that light is reflected from the beam splitter and toward the area exterior of the door. An observer behind the door may view the door exterior area including a visitor at the door entrance. The visitor, however, cannot see the observer through the beam splitter, because of the light reflected therefrom, thus increasing the overall security aspect. The design exploits the contrast sensitivity of the human eye as a function of field brightness.

Abstract: The apparatus of the present invention provides means for obtaining accurate, dependable, measurement of bearings and directions for geologic mapping in subterranean shafts, such as, for example, nuclear waste storage investigations. In operation, a laser beam is projected along a reference bearing. A pyramid is mounted such that the laser beam is parallel to the pyramid axis and can impinge on the apex of the pyramid thus splitting the beam several ways into several beams at right angles to each other and at right angles to the reference beam. The pyramid is also translatable and rotatable in a plane perpendicular to the reference beam.

Abstract: A diode imaging system using a single objective lens and a single cylindrical lens. This imaging system does not image perfectly point-to-point, and although not an apparent extension of imaging systems known in the prior art, it works advantageously for imaging beams from diode lasers having long narrow junctions used in pumping solid-state lasers.

Abstract: An objective lens system for microscopes comprising, in the order from the object side, a first lens unit which has a positive refractive power, comprises a positive meniscus lens component having a convex surface on the image side and allows a diverging light bundle to emerge therefrom, a second lens unit which has a positive refractive power, comprises at least one cemented surface having a negative refractive power and is movable along the optical axis, and a third lens unit having a negative refractive power, and adapted so as to favorably correct aberrations by moving the second lens unit in conjunction with thickness of a transparent plane parallel plate arranged between the first lens unit and an object to be observed through the objective lens system. This objective lens system has a high magnification, a large NA and a long working distance.