Abstract: The specification describes a Mach-Zehnder electro-optic modulator device in which the ridge containing the waveguides in the interactive electro-optic regions have re-entrant sidewalls. This shifts the peak in the RF field profile to below the surface of the ridge and closer to the peak of the optical field, thereby producing a device with reduced drive voltage.

Abstract: An apparatus for redirecting physical energy includes a substrate defining a first boundary of a region, a first electrode defining a second boundary of the region, the second boundary disposed opposite to the first boundary, a second electrode adjacent to the first boundary for cooperating with the first electrode to apply a non-uniform electric field to the region, the non-uniform electric field having electrical field intensities simultaneously including a first electric field intensity and a second electric field intensity, and a layer of material disposed in the region, the layer having a variable index of refraction responsive to the electric field intensities of the non-uniform electric field, the variable index of refraction including a first index of refraction in response to the first electric field intensity and a second index of refraction in response to the second electric field intensity.

Abstract: Optically generated charge carriers in an optically responsive medium, such as an optical switch, which are produced in response to a first pulse of optical radiation (P1), are de-excited by directing a second pulse (P2) of optical radiation into the medium. The second pulse occurs while the excitation produced by the first pulse remains coherent, and the relative phase of the first and second pulses is selected so that the second pulse destructively interferes with the excitation produced by the first pulse. The apparatus may be used as an optical switch or as a photodetector.

Abstract: An electrochromic device having successive layers of electrochromic electrolyte and counter-electrode materials. The counter-electrode material comprises an oxide of a mixture including at least two of vanadium, titanium and zirconium.

Abstract: The present invention pertains to an optical shutter device comprising one or more photon absorbing materials that convert photons to heat in less than 1 nanosecond and one or more thermochromic materials that undergo an increase or decrease in optical density at one or more wavelengths when the thermochromic material is heated from 25° C. to a temperature greater than 100° C. in less than 1 nanosecond.

Abstract: A method for operating an electro-mechanical grating device comprises the steps of: providing a beam of light; applying a first electrostatic actuation force for a certain amount of time thereby generating a first pattern in each group wherein the pattern comprises N different levels thereby diffracting the incident light beam into a first direction; and applying a second electrostatic actuation force for a certain amount of time thereby generating a second pattern in each group wherein the second pattern comprises N different levels thereby diffracting the incident light beam into a second direction different from the first direction. The electro-mechanical grating device has a plurality of spaced apart deformable ribbon elements disposed parallel to each other in the unactuated state and spanning a channel. The deformable ribbon elements are organized in groups of N elements wherein N is greater than 2.

Abstract: A spatial light modulator includes an upper optically transmissive substrate held above a lower substrate containing addressing circuitry. One or more electrostatically deflectable elements are suspended by hinges from the upper substrate. In operation, individual mirrors are selectively deflected and serve to spatially modulate light that is incident to, and then reflected back through, the upper substrate. Motion stops may be attached to the reflective deflectable elements so that the mirror does not snap to the bottom substrate. Instead, the motion stop rests against the upper substrate thus limiting the deflection angle of the reflective deflectable elements.

Abstract: An electrophoretic display element includes a capsule having a first, larger surface and a second, smaller surface. The capsule contains a suspending fluid and at least one particle dispersed within said suspending fluid. Application of a first electrical field causes the particle or particles to migrate towards the first, larger surface of the capsule, causing it to take on the visual appearance of the particles. Application of a second electrical field causes the particle or particles to migrate towards the second, smaller surface, allowing the capsule to take on the visual appearance of the dispersing fluid or of a substrate or electrode positioned behind the display element. Displays may be fabricated from multiple display elements arranged on a substrate.

Abstract: A three channel acousto-optic modulator may be used to implement a projection display or a scanner. Each of three channels are deflected differently by the modulator. The channels may correspond to the primary color planes.

Abstract: A laser wavelength conversion method and device for making the converted beam shape and the energy distribution point symmetrical which is suitable for high precision manufacturing and machining. First and second wavelength conversion devices are adjusted such that the phase matching orientations which give the minimum angular tolerances are orthogonal with each other. Fundamental wave is focused by focusing lens, and then incident on first device and second device, and is ejected as the cross shaped beam made of two orthogonal ellipses of the second harmonic waves. First device and second device are unified in order to eliminate the angular adjustment thereof for improving the working efficiency.

Abstract: There is disclosed a technique regarding an optical amplifier in an optical communications system. In order to effectively suppress optical surges during amplification of signal light, through a simple structure, there is provided an amplifying medium which amplifies input light and outputs the amplified light, and reflecting members are connected to the input and output sides of the amplifying medium. The reflecting members can reflect light with a predetermined optical wavelength different from a signal light wavelength contained in the input light.

Abstract: A bidirectional optical amplification system which includes an optical amplifier having an input and an output and configured to amplify wavelengths lying within a range of wavelengths and an optical coupling device. The optical coupling device includes a first port configured to receive a first optical wave in a first subrange of wavelengths lying within a range of wavelengths, a second port configured to receive a second optical wave in a second subrange of wavelengths lying within the range of wavelengths, an optical coupling output coupled to the input of the optical amplifier, and an optical coupling input coupled to the output of the optical amplifier.

Abstract: An optical amplifier having a two-stage construction using an erbium doped fiber (EDF) as a gain medium. The erbium dopant concentration is 1000 ppm, and the unsaturated absorption coefficient of the signal beam at 1550 nm is 1 dB/m. The length of the EDF 14-8 is 10 m, and the length of the EDF 14-12 is 70 m. The excitation light sources 14-6 and 14-10 are semiconductor lasers of 1.53 &mgr;m, and the excitation light power is 100 mW. Multiplexers 14-7 and 14-11 are inductive multi-layer film filters, and the gain equalizer 14-4 is a Fourier filter. The peak loss of the Fourier filter is 17 dB. The gain of the EDF 14-8 is 25 dB, and the gain of the EDF 14-12 is 15 dB. Two optical isolators are installed on a pre-stage amplifier, and one on a post-stage amplifier in order to prevent laser oscillation.

Abstract: Disclosed is an optical device with at least one lens and at least one swiveling observation tube, exhibiting the following characteristics: The observation tube comprises a base section fixedly connected to the optical device, and an eyepiece carrier which rolls along an arc of a circle so that swiveling can occur on the base section; a first rotatable deflecting mirror whose rotational axis orthogonally intersects the optical axis of an objective lens of the optical device and which is forcibly rotated by the movement of the eyepiece carrier on the base section; a second rotatable deflecting mirror is arranged in the eyepiece carrier and whose rotational axis orthogonally intersects the optical axis as deflected by the first deflecting mirror and which is forcibly rotated by the movement of the eyepiece carrier on the base section.

Abstract: A lens system comprising a plurality of lenses have a peripheral region and a central region. The central region includes a first lens of nonunity power. The central region has a different field of view from the peripheral region.

Abstract: A universal dual power telescope comprises two concentrically mounted telescopes combining functions of a tube-mounted finder and a regular telescope. The finder rotating inside the telescope includes a truncated prism for switching the telescope modes of operation. The dual function prism reflects images into the eyepiece either through the finder or telescope, while deflecting light rays and blocking formation of images through the other non-selected optical assembly. Both telescopes share the same eyepiece and focusing system. A low magnification finder or a high magnification telescope can be selectively engaged by changing an angular position of the prism's silvered plane.

Abstract: A stereoscopic image display device for providing a stereoscopic image by displaying images with a parallax on a viewer's left and right eyes is disclosed. The display device comprises the following. (1) A light source with selectively variable light-emitting regions for emitting light, wherein the light-emitting regions are disposed at various positions from a center of the light source. (2) An optical element having an optical axis extending through the center of the light source for condensing light emitted from the light source to each of the viewer's left and right eyes. (3) Spatial modulation means, disposed on an optical path from the light source to the viewer, for spatially modulating the light emitted from the light source.

Abstract: A binocular assembly which is held in optical alignment with a human being's eyes and without the use of a human being's hands. The binocular assembly includes a support member, a pair of optical systems positioned and mounted on the support member for magnifying items within view of the human beings eyes, an adjustment to laterally adjust and position the pair of optical systems laterally relative to one another to accommodate spacing between the human beings eyes, and a fastener for engaging the human being's head and securing the binocular assembly about the head of the human being.

Abstract: Light is supplied into a light incident surface 2 from a fluorescent lamp L enclosed by a silver foil sheet R, and parallelized illuminating light flux is taken out from a light exit surface 3. On a back surface 4 side of a light flux parallelizer 1, across or without a thin air layer 5, a polarization converter &Sgr; is disposed. The polarization converter &Sgr; reinforces the polarization function of the surface light source device through polarization conversion action accompanying reflection in the prism. At a position confronting the light exit surface 3 across an air layer 7, a polarization separating plate 8 is disposed. At a further outside, across an air layer 9, an exit light direction modifier 10 is disposed. A bright polarized illuminating light flux is emitted from a light exit surface 11. When applied to a backlight of a liquid crystal display, a liquid crystal display panel is disposed at a further outside of the exit light direction modifier 10.

Abstract: A retroreflective article that has a layer of optical elements and a multilayer reflective coating disposed on the optical elements. The reflective coating reflects light back into the optical elements so that it can be returned toward the light source. The multilayer reflective coating has multiple polymer layers and has layers that possess different refractive indices.

Abstract: An optical grating includes a sequence of grating lines, the sequence being such that each grating line is centered on a position which is an integer multiple of a line spacing distance from a datum position on the grating, the sequence of grating lines is non-periodic and the sequence of the grating lines is formed from N concatenated sub-sequences. Each sub-sequence includes a series of one or more instances of a respective grating line pattern. Such an optical grating has a structure that is more amenable to calculation of the grating lines necessary to achieve a desired characteristic. A method of calculating and fabricating such a grating is also disclosed.

Abstract: Coated optical substrates and a method of coating optical substrates with anti-reflective (AR) coatings are described. The composition of the coating is determined by material constraints such as adhesion, durability, ease of manufacture, and cost. The thickness of one or more layers of AR material is determined by minimizing the product of the Fresnel reflection coefficients for the coated article with the angle- and wavelength-dependent sensitivity of the human visual system. Preferred designs have a value of perceived reflectance, F, less than or equal to 1.25 Fmin where Fmin is the minimized perceived reflectance for the coated article. Coatings which have minimal perceived reflection while maintaining reflections with desired visually perceived colors are also described.

Abstract: Projection lenses and projection lens systems are telecentric between an illumination subsystem and a set of imagers. The lenses and systems can exhibit color fringing correction, uniform imager illumination, athermalization, and component articulation for improved imaging. The lenses and systems may be employed in display apparatuses, such as folded display apparatuses that have decreased footprint size, but long effective projection lengths.

Abstract: A piano lens according to the present invention includes a transparent base member disposed on a light emission side thereof or light incidence side thereof and a minute-transparent-ball disposing layer having at least minute transparent balls two-dimensionally in a single grain layer on the transparent base member so that the minute transparent balls disposed adjacent to each other should be disposed in contact with or close to each other, and a colored layer disposed so as to expose the minute transparent balls to outside on the light incidence side. The minute-transparent-ball disposing layer has an improved light transmission at a light emission side end portion of the minute transparent ball.

Abstract: The invention provides a dichroic prism capable of reducing displacements of projection pixels of colors caused by chromatic aberration of magnification. A dichroic prism is formed in the shape of a quadrangular prism as a whole by joining four rectangular prisms together. A red reflecting dichroic plane and a blue reflecting dichroic plane intersect to form substantially an X shape along junction surfaces of the prisms. The red reflecting dichroic plane is convex-shaped by partly changing the thickness of an adhesive layer for connecting the rectangular prisms together. Accordingly, since a red beam can be guided to a projection optical system while being enlarged, it is possible to reduce a projection image of the red beam to be projected onto a projection plane via the projection optical system. This makes it possible to reduce relative displacements of projection pixels of color beams caused by chromatic aberration of magnification.

Abstract: Projection lenses and projection lens systems are telecentric between an illumination subsystem and a set of imagers. The lenses and systems can exhibit color fringing correction, uniform imager illumination, athermalization, and component articulation for improved imaging. The lenses and systems may be employed in display apparatuses, such as folded display apparatuses that have decreased footprint size, but long effective projection lengths.

Abstract: A non-phase separable glass material for fabricating a GRIN lens comprises 5-20 mole % boron oxide and ratio R of network modifiers in mole % to the network former boron oxide in mole % is in the range of about 1-1.5. The melted preform of such glass material is extruded through an opening to form a glass rod where the extrusion process eliminates bubbles that may be present in the preform. Neodymium oxide may be added in the frit material for forming the preform to reduce friction forces in the extrusion process and reduces the stress in the glass rod. Centerless grinding may be performed to control the diameter and roughness of the surface of the rod to control the diffusion parameters during the subsequent ion-exchange.

Abstract: A zoom lens system has, from the enlargement side, a first lens unit having a negative optical power and having a lens element including a diffractive optical surface, a second lens unit having a positive optical power, and a third lens unit. Zooming is performed by varying the distances among the first through third lens units. The following conditions are fulfilled: |&phgr;Dn/&phgr;1|<0.06 −0.8<&phgr;n/&phgr;W<−0.3 where &phgr;Dn represents the diffractive optical power of the first lens unit, &phgr;1 represents the refractive optical power of the lens element including the diffractive optical surface, &phgr;n represents the composite optical power of the diffractive and refractive optical powers of the first lens unit, and &phgr;W represents the composite optical power of the diffractive and refractive optical powers of the entire lens system in the shortest-focal-length condition.

Abstract: A zoom lens system which includes a positive first lens group and a negative second lens group, in this order from the object side; wherein zooming is performed by moving the first lens group and the second lens group, and by varying the distance between the first lens group and the second lens group; wherein the zoom lens system satisfies the following condition: −7.0<fT/f2G<−5.1 . . .   (1) wherein: fT designates the focal length of the entire lens system at the long focal-length extremity and f2G designates the focal length of the second lens group.

Abstract: A laser irradiation device generates a linear laser beam extending in one direction, which is irradiated toward the substrate 20 to be processed. The length Lh of the emitted linear laser beam in the major axis direction is adjusted in accordance with a size of the substrate 20 to be processed or the area to be processed within the substrate 20. The adjustment of the length Lh is performed by altering the distance X between a pair of cylindrical lenses 43 and 5 of the optical system for adjusting the generated laser beam in the direction corresponding to the length Lh direction of the linear laser beam, in accordance with the required length Lh. The alteration of the distance X is performed by altering the position of one of the cylindrical lenses 43 and 5 within the optical path in forward and backward direction. The lens is, for example, one having more flexibility of layout in the optical system than the other.

Abstract: The invention comprises a mounting assembly for an optical sight. In accordance with one embodiment of the invention, a mounting assembly may comprise a first foot (552) and a second foot (556). The first foot (552) may include a top (563), a first side (570), and a second opposite side (574). The top (563) may have a first tab (566) sized to fit a first recess (568) of a sight (20). The first side (570) may engage a first edge (572) of a rail (562). A first clamp (554) may be coupled to second side (574) of the first foot (552) to engage in combination a second edge (576) of the rail (562). The second foot (556) may include a top (586), a first side (594), and a second opposite side (596). The top (586) may include a tab (590) sized to fit a second recess (592) of the sight (20) substantially normal to the first recess (568). The first side (594) may engage the first edge (572) of the rail (562).

Abstract: A lens holder includes which a bottom cover, a top cover, sliding means and clipping means for holding lens assemblies in an optical lighting system. The bottom and top covers have a plurality of slot extensions lining the interior of the two covers. The top cover clips to the bottom cover by a set of clips on each side of the top cover to a set of clip slots on each side of the bottom cover. Lens assemblies can consist of lenses assembled in a holder along with individual lenses which can slide into between slot extensions.

Abstract: A stable resonator for a ring-down cavity spectroscopy cell having an optic axis. The resonator includes two Brewster's angle retroreflector prisms, each having a plurality of total internal reflection surfaces, with one of the total internal reflection surfaces of at least one of the prisms having a curved surface (either a ground curved surface or a surface curved by the addition, through optically contacting or gluing, of a plano-convex lens to the surface). The prisms are disposed in alignment along the optic axis of the resonator. A spherical mirror or lens, tilted from normal incidence to produce a desired degree of astigmatism, mode matches the radiation into the resonator. One or both of the prisms can be rotated so that light rays enter and leave a surface of the prism nearly at Brewster's angle to the normal of the prism surface. This feature maintains alignment between the prisms and allows the resonator to be tuned.

Abstract: A stable resonator for a ring-down cavity spectroscopy cell having an optic axis. The resonator includes two Brewster's angle retroreflector prisms, at least one prism having greater than two total internal reflection surfaces. The prisms are disposed in alignment along the optic axis of the resonator. One or both of the prisms can be rotated so that light rays enter and leave a surface of the prism nearly at Brewster's angle to the normal of the prism surface. This feature maintains alignment between the prisms and allows the resonator to be tuned. One of the total internal reflection surfaces of at least one of the prisms may be a curved surface (either a ground curved surface or a surface curved by the addition, through optically contacting or gluing, of a plano-convex lens to the surface).

Abstract: A catoptric reduction projection optical system (100), a projection exposure apparatus (EX) and a method using same. The catoptric reduction projection optical system is capable of forming a reduced magnification image of an object present on a first surface (R) onto a third surface W. The system includes a first catoptric optical system (10) capable of forming an intermediate image of the object onto a second surface (IM) and comprises a first mirror pair having a first reflective mirror (M1) and a second reflective mirror (M2).

Abstract: A resonant absorption cell filled with a gas, selected in accordance with the wavelength of the laser radiation of interest, such as DF. The gas within the cell is maintained at substantially atmospheric pressure. The energy state of the gas within the cell is raised by either external resistance heating or optical pumping. In an increased energy state, gas molecules resonate with the incoming laser radiation causing the molecules to absorb incident photons before the gas molecules have a chance to re-radiate the captured photons, collisions with other gas molecules within the cell transfer the excitation energy into heat in order to filter out laser radiation but past all other wavelengths.

Abstract: A signal recording device includes a signal inputting unit for inputting a signal to be recorded on a recording medium, as well as a dropout detector which detects a dropout portion of a signal output from the signal inputting unit and generates a pulse signal corresponding to the detected dropout portion. A muter mutes the signal output from the signal inputting unit during the pulse signal period. The signal recording device records on a recording medium, a signal output from the signal muter during the pulse signal period and a signal output from the signal inputting unit during all other times. Therefore, in the signal recording device of the present invention, since a signal during a dropout period is muted before being recorded, upon playback of the recorded signal, a dropout compensator in a reproducing device identifies the muted signal period as the dropout period and accurately compensates for the dropout. Therefore, noise caused by the dropout can be prevented.

Abstract: A signal processing device having a feature of analog-to-digital converting a burst signal has a feature of selecting a data bus to notify a disk control device of a conversion result via an NRZ data bus. The disk control device stores the result of the analog-to-digital conversion of the servo positional signal. The positional signal of a head of the disk device is digitalizes in a R/W channel. Sampling for digital conversion is performed in only a window which is defined only in the vicinity of peaks of the positional signal. The values of peaks which are obtained by sampling are averaged by an averaging circuit. This enables the influence of noise occurred outside of the window to be eliminated. Although the noise in the window is sampled, its adverse influence is suppressed by the averaging processing.

Abstract: A data recording and reproducing apparatus for recording and reproducing data on azimuth tracks of a magnetic tape in which the data may be audio data or computer data in any of several different computer data formats includes a controller that controls the recording and reproducing signal processing so as to be responsive to the four different kinds of data formats such that main data and subdata may be separated from the audio data and subcodes and error correction codes generated and appended to the data stream as required.

Abstract: A method and apparatus for writing clock data to a storage medium, such as a disk, is disclosed. The storage medium has tracks on which data are stored. Clock data is written to a present track on the storage medium. The written clock data is read from said present track. Clock data for a subsequent track on the storage medium is generated from the clock data read from said present track. The phase of the generated clock data for the subsequent track is compared with a reference timing signal and the phase of the generated clock data for the subsequent track is adjusted in accordance with said comparison. Said phase adjusted clock data for the subsequent track is written to said subsequent track. Phase errors can be significantly reduced and, for practical purposes, substantially eliminated. It is not necessary to provide a dedicated clock read/write head.

Abstract: A digital signal recording method and apparatus for recording digital signals of two channels along tracks on a magnetic tape in a helical pattern by employing at least two pairs of rotary heads mounted on a rotatable drum oppositely to each other and by making use of a read-after-write function, the paired heads being disposed adjacent to each other. The input signal to be recorded is compressed such that the digital signal recording period for each relevant track is shortened by a ratio corresponding to a time for which a write period for one track and a read period for adjacent one overlap each other. The write period and the read period are thus prevented from overlapping. The reproduced signal for the read-after-write function is prevented from being masked by an input signal recording current.

Abstract: A magnetic storage system capable of separating thermal signals from data signals is disclosed. The magnetic storage system includes a magnetic media and a head associated with the magnetic media. The head includes a magneto-resistive element which is biased by a modulated bias current. The modulated bias current modulates thermal signals to a first frequency and modulates data signals to at least a second frequency. A method of separating thermal signals from data signals read from a magnetic storage media is also disclosed. The method includes the steps of (1) providing a head for reading information from the magnetic storage media, the head having an MR element; and, (2) biasing the MR element with a modulated bias current.

Abstract: A data storage system for use with a tape cartridge storing data in a serpentine pattern on tape media, and having a memory device for storing a device block map for the tape median, comprises tape drive, or a loading mechanism, which first positions the tape cartridge at memory interface for transfering the device block map from the memory device to a processor, and subsequently positions the tape media for reading and/or writing. The processor processes the device block map from the memory device for optimal retrieval of the serpentine pattern data of the tape media. The processing of the device block map occurs while the tape media is positioned for reading and/or writing, so that the processor begins the retrieval reading process immediately upon the positioning of the tape media. In another aspect of the invention, a robotic accessor of an automated data storage library moves the tape cartridge to the tape drive.

Abstract: A cartridge tape drive for use with a tape cartridge includes a temperature sensor for determining the temperature of the tape cartridge and a control device responsive to the temperature sensor for automatically adjusting the speed of the tape when a temperature threshold value is realized. The cartridge tape drive includes a housing including an opening dimensioned to receive the cartridge and a device for supporting the cartridge within the housing, a magnetic head within the housing, a driver for moving the cartridge in operative engagement with the magnetic head, a temperature sensor for determining the temperature of the cartridge when the cartridge is in operative engagement with the magnetic head, and a control device responsive to the temperature sensor for automatically adjusting the speed of the tape when a temperature threshold value is realized.

Abstract: A tracking control apparatus for a tape-shaped recording medium is operative, prior to carrying out actual reproduction, to measure times from the time point serving as the reference phase position within one period of the rotary drum to the time points when timing signals of respective recording areas of the tape-shaped recording medium are detected by the head, and to calculate average values every respective recording areas of the measured times to generate a reference value on the basis of the maximum value and the minimum value of the calculated average values of the respective recording areas.

Abstract: A method of providing the servo pattern for detecting fine defects in the servo burst signals of a hard disk drive (HDD) comprises the steps of writing a preamble portion for providing a servo sync signal in reading servo data together with a gap to inform of a servo sector, writing a servo address mark (SAM) for notifying the start of the servo to provide a sync signal to read the following gray code, writing the gray code for providing the identification data ID of a track, and writing a burst signal portion consisting of multiple repetition of the position error signal required for even or odd numbered track data and track following.

Abstract: A servo writer for writing servo code to a magnetic tape having a width, the servo writer comprising a tape head including a plurality of write elements and being configured to write servo code to a plurality of bands across substantially the entire width of the tape. A method comprising providing a tape having a width; and writing servo code on the tape using a servo writer configured to transport the tape in a length direction normal to the width, and configured to write servo code in linear bands along the length of the tape, the bands together occupying substantially the entire width of the tape.

Abstract: An actuator is provided with a step so as to allow FPC mounting surfaces of a read/write FPC band and of a relay FPC to be level with each other. Pointer information P4 in a ROM table is used to refer to a RAM table to acquire offset correction data. On-track control is effected at a cross point of two-phase servo signals N and Q. A value of this cross point is measured to find a position sensitivity correction value. A gap corresponding to encode loss is provided at the trailing position of each of sectors. In read operation, a sector pulse is generated with a delay corresponding to decode loss.

Abstract: A technique for measuring a position error signal of a disk drive, includes measuring the width of a track by sequentially following two adjacent tracks upon turning on power, and updating a percentage of the position error signal according to the measurement of the track width.

Abstract: An apparatus of the present invention is a magnetic recording/reproduction apparatus for pulling out a magnetic tape from a tape cassette and winding the magnetic tape around a rotary head cylinder, having a rotary head, for a predetermined arc, for recording/reproducing the magnetic tape.