Abstract: A microscope objective lens system which comprises a front and a rear lens group, the former comprising a first positive meniscus lens component, a second positive lens component, a third positive cemented lens component and a fourth positive cemented lens component, and the latter comprising a fifth cemented lens component, the system enabling to achieve the flattening of an image plane widely towards the surrounding area of visual field.

Abstract: The invention contemplates a multiple-element microscope objective assembly which is removably mountable to a microscope body and which includes a front element adapted for immersion contact with a liquid medium through which a microscopic object is to be observed. The invention features an externally accessible control adjustment for selectively axially positioning one of the optical elements of the objective with respect to the rest of the assembly such that a corrective optical adjustment is made for such change in refractive index as may characterize the use of one vs. another liquid-immersion substance, thereby enabling the microscope to preserve its normal focusing action consistently for use of the objective with a plurality of different immersion substances having different refractive indices.

Abstract: An in-line, three element, large diameter, optical display lens having a front convex-convex element, a central convex-concave element, and a rear convex-convex element. The lens, used in flight simulators, magnifies an image presented on a televison monitor and, by causing light rays leaving the lens to be in essentially parallel paths, reduces eye strain of the simulator operator.

Abstract: A retrofocus type wide-angle lens system for use in micro readers, micro printers, facsimiles, etc. comprising a first negative meniscus lens component, a second positive lens component, a third biconcave lens component, a fourth positive lens component, a fifth positive lens component and a sixth negative meniscus lens component. Said lens system assures high resolution even at marginal portions of image and has a high aperture efficiency.

Abstract: A rear conversion lens comprises a divergent forward lens group comprising three components and a divergent rearward lens group comprising two components. The three components forming the forward lens group are, in order from the object side, a biconvex positive lens, a biconcave negative lens with its more curved surface facing the image side, and a positive lens with its more curved surface facing the object side. The two components forming the rearward lens group are, in order from the object side, a biconcave negative lens with its more curved surface facing the image side and a biconvex positive lens with its more curved surface facing the object side.

Abstract: A high resolution objective lens system for ultra microfiche designed for a magnification of 1/150x.about.1/120x and comprising a first cemented lens component consisting of a positive lens element and a negative lens element, a second positive lens component, a third positive lens component, a fourth negative cemented lens component, a fifth positive lens component and a sixth cemented lens component consisting of a negative meniscus lens element and a positive meniscus lens element.

Abstract: The invention concerns a high-resolving objective particularly for use in aerial photography based on the double-gauss objective type, covering a wide spectral range, and which at a relative aperture of 1:4 images an image field of 2.sigma.>40.degree. without aberrations.

Abstract: First and second plates are formed with like periodic patterns. A laser beam illuminates the second plate through the alignment marks of the first plate to provide a pair of diffracted beams that are detected with alignment being indicated when the beams are of the same intensity.

Abstract: The present lens system is capable of providing both a zooming operation and also a relatively efficient and economical macrophotography mode of operation. The zoom lens system contains the basic conventional lens groups of a focusing lens group, variator lens group, compensator lens group and relay lens group. These individual lens group function in a conventional manner during a zooming mode of operation. However, during the macrophotography mode of operation, the individual lens element that form the relay lens group are capable of coordinate movement with other lens elements in the lens system to provide a relatively compact and economical lens design for macrophotography.

Abstract: A wide angle zoom lens system having a compact configuration is provided for use with 35 mm single lens reflex cameras. The zoom lens system includes two lens groups that can be relatively displaced along the optical axis to provide variation in focal length. The first lens group has a negative refractive power and the second lens group has a positive refractive power. A wide field angle is provided while minimizing the number of optical lens elements that constitute the two group zoom lens system.

Abstract: A hologram of a wave front reflected by the end of a primary standard, either produced by exposure of a plate in the apparatus or synthesized by computer, is illuminated by a laser with a direct beam and with a beam reflected from the end of a standard to be measured mounted in a reference position. Interference fringes are produced on a screen and the standard to be measured is moved from a reference position to a position in which the reflected wave front coincides with the wave front recorded by the hologram while the fringes are counted to determine the difference in length.

Abstract: An optical apparatus for use in conjunction with spherically shaped concave mirrors for substantially eliminating aberrations in the reflections from such mirror. The mirror cooperates with a light source or a light receiver placed in the vicinity of but off-set relative to the natural focal point of the mirror. A plane parallel, transparent plate is placed between the mirror and the light source or receiver and it has a size so as to intercept light rays between the mirror and the light source or receiver and which respectively result in or are caused by light beams oriented parallel to the optical axis of the mirror. Use of the invention for additionally correcting astigmatism and chromatic aberrations caused by spherical mirrors is disclosed. Also disclosed is the use of the invention in connection with large spherical mirrors forming part of light curtain arrangements.

Abstract: A miniaturized, super-wide angle zoom lens system of the two lens group type wherein barrel shaped distortion aberration in the wide angle position is compensated for by providing one of the lenses with an aspherical surface.

Abstract: A zoom lens system consists of a front lens group A comprising a negative meniscus lens L1 convex to front (i.e. object side) and a positive lens L3 having the face of greater curvature faced to front, and a rear lens group B comprising a positive lens L4 having the face of greater curvature faced to front, a positive menisucs lens L5 convex to front, a negative lens L6 having the face of greater curvature faced to rear and a positive lens L7. The front and rear lens groups A and B are moved in the opposite directions along the optical axis thereof to vary the focal length thereof.

Abstract: A velocity servo for a continuous scan Fourier interference spectrometer of the double-pass retroreflector type having two "cat's eye" retroreflectors uses an open-loop, lead-screw drive system for one retroreflector with compensation for any variations in speed of drive of the lead screw provided by sensing any variation in the rate of reference laser fringes, and producing an error signal from such variation used to compensate by energizing a moving-coil actuator for the other retroreflector optical path, and energizing (through a highpass filter) piezoelectric actuators for the secondary mirrors of the retroreflectors.

Abstract: A lens system for photographic cameras which has a very short total length and wherein aberrations are favorably corrected. Said lens system comprises a first positive meniscus lens component, a second biconcave lens component and a third cemented doublet component, and said lens system satisfying the conditions enumerated hereunder:(1) 0.23f<.SIGMA.d<0.3f(2) 0.55f<f.sub.1 <0.59f(3) -0.37f<f.sub.2 <-0.32f(4) n.sub.1 >1.71(5) n.sub.2 <1.67(6) .vertline.r.sub.7 .vertline.>4.8f(7) 0.26f <-r.sub.6 <0.34f(8) .vertline.r.sub.3 .vertline./r.sub.4 >6.0(9) .nu..sub.1 -.nu..sub.

Abstract: The specification describes an interference optical measuring or sensing device, comprising a light source, a beam splitter, two component light paths and a radiation sensor for a multiple hole centrifuge rotor. When the rotor is in motion sample cells and the counter-weight move successively through the component light paths and at a particular position have both light paths extending through them. There is furthermore an arrangement for producing a position signal indicating that a selected hole is in a certain position in which it has both component light paths extending through it. A control arrangement ensures that the measuring device is activated briefly in the predetermined position of the selected hole. The light source continuously supplies light between the periods of activation of the measuring device.

Abstract: A two lens group type of miniaturized zoom lens system having a minimum wide end viewing angle of 76.degree. and a zoom ratio at least 2.3. The first or object side lens group includes at least two positive and two negative lenses with the image side lens being positive. The second or image side lens group includes at least two positive lenses facing the object. The variable aperture is mounted in front of the second lens group and the fixed aperture, which may be proportionally movable, is mounted behind the second lens group. The overall lens system satisfies the following conditions: ##EQU1## wherein: Z is the zoom ratio (Z=f.sub.T /f.sub.W),f.sub.1 is the focal length of the first lens groups,f.sub.2 is the focal length of the second lens group,f.sub.W is the focal length in the wide angle position,f.sub.T is the focal length in the telescopic or narrow angle position, andr.sub.

Abstract: An interferometer, preferably of the Michelson type, is disclosed, in which the reflectors associated with the interferometer arms are stationary, and scanning is accomplished by displacement of a single wedge-shaped refractive element in one of the arms. The reflectors are preferably retro-reflectors rather than flat mirrors in order to minimize the effects of chromatic dispersion. A Moire scale may be used to measure the position of the wedge-shaped refractive element.

Abstract: A zoom lens system comprises, in order from the object side, a positive first lens group, a negative second lens group, a positive third lens group, a negative fourth lens group and a positive fifth lens group. The first lens group includes a positive lens component comprising a negative and a positive lens cemented together, and a positive meniscus lens component convex to the object side. The second lens group includes a negative lens component and a negative lens component comprising a negative lens and at least one positive lens cemented together. The third lens group includes at least one positive lens component and a positive lens component comprising a positive and a negative lens cemented together. The fourth lens group includes a negative lens component. The fifth lens group comprises a forward and a rearward group spaced apart a substantial distance from each other by an air space.