Abstract: Optical apparatus for monitoring the relative positioning of first and second members which are movable relative to each other includes radiation means for generating an optical wavefield which provides, over a given area which has a predetermined location relative to the first member at least when the first member is in a given position relative to the second member, a distinctive light intensity distribution. The distinctive light intensity distribution results from at least two wavefronts that differ from each other in curvature in each of two mutually orthogonal planes. The radiation means preferably includes a source of radiation, a diffracting element and a focussing element. The diffracting element coacts with the source of radiation to provide said at least two wavefronts and the focussing element produces an image of the diffracting element at said predetermined location at least when the first member is in said given position relative to the second member.

Abstract: A compact zoom lens system with high zooming ratio for which the range of focal length is 16 to 192, i.e., the zooming ratio is 1:12, and aperture ratio is large and which comprises a focusing lens group having positive power, a variator lens group having negative power, a compensator lens group having negative power, an erector lens group having positive power and a master lens group.

Abstract: A compact retrofocus type wide-angle photographic lens system wherein aberrations are favorably corrected and which comprises a first lens component having negative power, a second lens component having positive power, a third negative lens component, a fourth positive meniscus lens component and a fifth positive lens component, said wide-angle photographic lens system being so adapted as to meet the following conditions.f < f.sub.B < 1.2f (1)0.5f < .SIGMA.d < 0.57f (2)0.55f < f.sub.4,5 < 0.65f (3).vertline. r.sub.a .vertline. < 1.

Abstract: A retrofocus type wide angle objective lens comprising from front to rear a diverging first lens component having a non-spherical surface formed therein, a converging second lens component, a diaphragm, and a converging third lens component, whereby the second component includes a positive front lens followed by a negative lens, said positive and said negative lenses defining therebetween a first air lens of which the focal length is negative in sign, and the third component includes a negative front lens followed by a positive lens, said negative and said positive lenses defining therebetween a second air lens of which the focal length is also negative. The provision of these first and second air lenses facilitates achievement of good correction of aberrations particularly astigmatism which would be otherwise under-corrected by the introduction of the non-spherical surface into the first component.

Abstract: A large-aperture photographic lens system of variant Gauss type which has a back focal distance nearly as long as 70% of the total focal distance of the entire lens system and wherein aberrations are favorably corrected.

Abstract: A varifocal object selectively focusable upon a normal range of object distances and a substantially shorter macro range can be supplemented by a negative component of one or more lenses whose focal length is less than the depth of the macro range and which forms a virtual image of a nearby object on the object plane of the objective when the latter is adjusted to a predetermined closeup position. A correlating linkage between a seat for the supplemental component and a control member designed to establish the closeup position serves to index the control member in that position or to prevent the emplacement of the supplemental component if the objective is in a different position.

Abstract: The present invention relates to a focusing lens group of a telephoto zoom lens having a long range of focal length. The focusing lens group consists of four sub-groups, wherein first, second, and fourth sub-groups are fixed while a third sub-group can be shifted for focusing.And the first sub-group has a positive refractive power and the second sub-group has a negative refractive power. The third sub-group has a positive refractive power and the fourth sub-group has a negative refractive power. As a result, the variation in the image quality at a time when the telephoto zoom lens is focused will be eliminated and the diameters of the lenses in the second, third and fourth sub-groups will be smaller than that of the first sub-group.

Abstract: A three element lens comprising two outer positive meniscuses and a central negative meniscus with all three elements concave to the aperture stop between the negative meniscus and a positive element.

Abstract: A small-area focus solar concentrator comprising a linear echelon refractor and a linear echelon reflector. The increments of the refractor are crossed at approximately 90.degree. to the increments of the reflector. The refractor and reflector cooperate to focus solar radiation incident on the front surface of the refractor to a small area focus in front of the refractor.The refractor-reflector structure permits relatively low cost, high power concentrators using refractor-reflector matrices. Also, the refractor-reflector structure can be used to focus normal or non-normal incident radiation outside the path of the radiation to reduce or eliminate blockage of the radiation by an absorber located at the focus.

Abstract: An optical system utilizing a lens element having a spherical surface incorporating a narrow bandpass filter, with the spherical surface being of such configuration that converging rays are normal to its surface, thereby permitting the narrow bandpass filter to operate with minimum bandwith, thus maximizing the rejection of unwanted background radiation. The surface of the lens element opposite the surface having the narrow bandpass filter may incorporate a dichroic filter, enabling the lens element to operate in a dual mode, with the dichroic filter reflecting entering visible light energy but being transparent to laser light energy, and the narrow bandpass filter thereafter eliminating wavelengths outside a given laser spectrum. As an example, my novel lens element may be used as a part of a catadioptric objective system sensitive to both visible and laser light frequencies.

Abstract: A gauss type photographic lens system having a large aperture ratio which comprises five components of six lens elements and wherein symmetry of coma is improved and curvature of field, spherical aberration, etc., are favorably corrected by enlarging the airspace comprising a stop and increasing refractive indices of the lens elements arranged on both the sides of said stop.

Abstract: Film of a known refractive index whose thickness is to be measured is illuminated by a white light beam. Two wave fronts from both sides of the film are directed to an interferometer. The wave fronts are out of phase in accordance with the thickness of the film. The two wave fronts are amplitude-split, respectively, by the beam splitter of the interferometer. Two of the split wave fronts are tilted by tilting means in the interferometer. The other two split wave fronts, as well as the two tilted wave fronts, are directed to an interference surface. Thus, there is formed a white interference pattern on the interference surface. The white interference pattern has a middle peak and two side peaks. The space interval between these peaks is measured by a scanner. By knowing the peak-to-peak interval, it is possible to discriminate the space interval between both sides of the film.

Abstract: An improved transparent corneal contact lens and method of making the same is disclosed. The lens has an outer edge portion of about 0.7 mm effective radius and a thickness of between about 0.003 to about 0.004 inches. The apex of the outer edge is positioned to be at or below the center line between the posterior and anterior surfaces of the outer edge portion to enable lacrimal fluid to flow between the lens and the corneal surface as well as substantially reduce the possibility of collision by the upper lid during closing. The method involves slowly heating, maintaining and cooling the lens and thereafter cutting the lens within a specified time after it has reached ambient temperature, which enables the lens to be more thinly cut.

Abstract: A catadioptric wide-angle lens is disclosed, in which a convex surface of a positive meniscus lens, a convex surface of a negative meniscus lens and a concave surface of a spherical mirror face an object and an image. These elements are arranged in order along the optical axis. The positive meniscus lens is dense crown glass or phosphate dense crown glass. The negative meniscus lens is dense flint glass.

Abstract: An improved Gauss type lens system having a long back focal length with a relatively high aperture ratio is provided. The Gauss type lens system can comprise a five group, seven lens element system wherein the overall length of the lens system is less than 90 percent of its focal length. The Gauss type lens system has design parameters within the following ranges, wherein the sub-numbers refer to respective lens characteristics, sequentially measured from the object to image side:1.7 < r8/r6 < 1.9, (1)0.9 < r10/r8 < 1.2, (2)0.67 < (d.sub.6 + d.sub.7)/(d.sub.3 + d.sub.4) < 0.87, (3)1.65 <n.sub.2 < 1.72, (4)n.sub.5 > 1.72, n.sub.6 > 1.72 (5)wherein,r represents the radius of curvature;d represents the axial distance, andn represents the refractive index.

Abstract: A medium magnification objective for video disks comprising four single lenses for which the number of lenses constituting the objective is small, the working distance is large and flatness of image is high.

Abstract: An apparatus and method are provided for determining the extinction coefficient of an atmospheric scattering medium utilizing a single-ended optical system having a predetermined transmitter field of view and two concentrically arranged cooperating optical receivers, wherein backscattered light from near and far receiver fields of view for each of a series of transmitted light pulses is collected by the respective receivers. Optimum reception is achieved for both near and far field scatterers and the received signals are selectively processed by a processor which may include, for example, integration, summation, and differentiation steps that automatically yield extinction coefficient data under a wide range of environmental conditions without requirements of extreme apparatus stability, continuous monitoring, or calibration of the apparatus.

Abstract: A wide angle photographic lens system comprises, in the order from the object side, a first lens component which is a positive lens having its more convex surface facing the object side, a second lens component which is a negative meniscus lens having its convex surface facing the object side, a third lens component which is a biconvex lens having its more convex surface facing the object side, a diaphragm, a fourth lens component which is a biconcave lens, a fifth lens component which is a positive meniscus lens having its convex surface facing the image side, and a sixth lens component which is a biconvex lens. Four distinctive optical conditions are characteristic of the lens system.

Abstract: A compact large-aperture photographic lens system having six-component seven-element lens configuration and comprising a first, second, third, fourth, fifth and sixth lens components, in which the first and second lens components are positive meniscus lenses, the third lens component is a negative meniscus lens, the fourth lens component is a cemented meniscus doublet, the fifth lens component is a positive meniscus lens and the sixth lens component is a positive lens, the compact large-aperture photographic lens having a short overall length and long back focal length.

Abstract: In a variable focus objective an axial air space between a negative front lens and a positive rear lens component is variable for zooming. The first component is movable for focusing independently of the rear component and provided with a variable air space defined therein to facilitate focusing down to short object distances while preserving high grade imagery for close objects throughout the zooming range and assuring a good uniformity of image quality throughout the entire image region even at the full open aperture.