Matches 651 - 700 out of 744 < 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 >
Match Document Document Title
4885734 Diffraction grating using birefringence and optical head in which a linearly polarized beam is directed to a diffraction grating  
A diffraction grating comprises a birefractive sheet (11) having a corrugated surface with at least each groove filled with a mass (12) of a material of a refractive index which is substantially...
4869568 Arrangement comprising a planarly extending thin-film waveguide  
An arrangement comprising a planarly extending thin-film waveguide, which is particularly useful when employed with devices that require a relatively high power and highly focused laser radiation....
4834485 Integrated fiber optics transmitter/receiver device  
An integrated transmitter/receiver system which uses a hybrid component for both the light source and the light detector, with holographic optical elements for dividing the light beam into two or...
4832445 Security diffraction devices difficult to exactly duplicate  
Holograms, including diffraction gratings, and methods of making them, that reconstruct an image which changes as the hologram is tilted with respect to the viewer and in a manner that images...
4829506 Apparatus for optically scanning an information plane  
An apparatus for scanning the information plane of an optical record carrier with a radiation beam from a diode laser. The reflected radiation from the information plane is separated from the...
4795236 Optical low pass filter utilizing a phase grating  
An optical low pass filter including a phase grating, wherein the grating is implanted inwardly from the surface of a substrate, the grating having a uniform repetitive period and having a...
4793680 Induced grating devices and method of making same  
It has been found that when a pulsed high-power laser beam is incident on the surfaces of a wide variety of materials, ripples are produced on such surface. This is due to interference between...
4792197 Fabrication method and equipment for diffraction gratings  
A method and equipment for fabricating two diffraction gratings having the same period but phases that are shifted by λ/4 on a work to be treated. A laser beam is divided into two light beams and...
4787694 Optical fibre polarizer  
A frequency selective optical polarizer is formed by pressing a length of single mode polarization maintaining fiber 12 against a ribbed plate 10 in order to generate a distributed strain pattern...
4787690 Cut-off filter for integrated optics  
A cut-off filter for integrated optics, which filter has a form of a relief-like surface grating on a film or strip waveguide, is formed in a portion of the strip waveguide having a reduced layer...
4776696 Optical system for high resolution spectrometer/monochromator  
An optical system for use in a spectrometer or monochromator employing a mirror which reflects electromagnetic radiation from a source to converge with same in a plane. A straight grooved,...
4733943 Pickup for optical disc  
A pickup system for an optical disc reading/recording apparatus in which a micro Fresnel lens, formed with concentric circular gratings, is used in place of an optical element, such as an objective...
4729640 Liquid crystal light modulation device  
A liquid crystal light modulation device conprises a pair of substrates at least one of which is transparent, a diffraction grating formed between or on at least one of the substrates, a liquid...
4728165 Superimposed fast transient and permanent holographic gratings  
A method is disclosed for producing a superimposed fast transient grating on a permanent holographic grating which provides high scattering ability, fast modulation response times, and the...
4676597 Imaging monochromator  
The monochromator presents, in the plane of the slit (5), a mirror (6) which reflects the radiations comprised within the spectrum portion selected by the slit (5) towards the grating (3)...
4660934 Method for manufacturing diffraction grating  
A method for manufacturing diffraction grating, in which after forming, on a substrate, one of a negative type photoresist film (an N film) and a positive type photoresist film (a P film) to cover...
4633171 Window function for an aperture window  
A window function optimum for apodization of diffraction at an aperture of a Bragg Cell spectral analyzer. A window function is derived which is simpler to realize and which comes very close to an...
4626069 Optical power divider  
An optical power divider for use with one incoming and a plurality of outgoing glass fibers includes an imaging device arranged on an optical axis between the incoming and outgoing glass fibers. At...
4623214 Holograms  
An integral direct viewing hologram device and an article useful in the manufacture of hologram devices are predicated upon a particular set of components grouped according to a number of...
4618214 Method of fabricating a controlled harmonic binary grating  
A method of fabricating a controlled harmonic grating having both binary magnitude and phase transmissions in which specified harmonics are enhanced and/or suppressed. The summing of a number of...
4592618 Holographic recording and related reading process  
A holographic process is provided for recording-reading by means of index strata in the volume of a photoexcitable storage medium. This process consists in causing two beams to interfere in this...
4560249 Method of forming diffraction gratings and optical branching filter elements produced thereby  
A method for making a diffraction grating utilizing a laser source, a beam splitter to split the light from the laser source into two light fluxes, a collimator to convert each light flux into a...
4556950 Incoherent optical processor  
An optical signal processor operating on interferometric principles serves to perform real time Fourier transformations on the intensity distribution of one-dimensional incoherent input light sources.
4545646 Process for forming a graded index optical material and structures formed thereby  
A process for depositing on the surface of a substrate a layer of a chosen material having continuous gradations in refractive index in a predetermined periodic pattern. The substrate is exposed to...
4521075 Controllable spatial incoherence echelon for laser  
A system for achieving very uniform illumination of a target. A beam of broadband spatially-coherent light is converted to light with a controlled spatial incoherence and focused on the target. An...
4514053 Integral photosensitive optical device and method  
An integral optical device is disclosed that is composed of a photosensitive glass having an optical pattern developed therein by a refractive index change due to formation of colloidal metal...
4484797 Diffractive subtractive color filter responsive to angle of incidence of polychromatic illuminating light  
A variable index-of-refraction optical medium of certain minimum thickness and periodicity with respect to the wavelength of incident light--if it meets certain specified constraints with respect...
4448485 Harmonic generation using a surface of metal particles  
Metal ellipsoidal particles are deposited on an ordered array of silicon dioxide posts. Each of the particles has dimensions that are less than the wavelength of a fundamental beam to be used in...
4443088 Focusing screen  
A focusing screen includes a plurality of light deflecting portions, each of which includes a prism component having a light deflecting function for providing part of an out-of-focus image with...
4440839 Method of forming laser diffraction grating for beam sampling device  
A combined holographic grating that samples a high energy laser beam and focuses the sample into a spot is formed by the cross-modulation term of a linear holographic grating and a holographic zone...
4433437 Method and apparatus for verifying security labels  
Electro-optical apparatus for verifying the authenticity of security labels of the type having a series of lenticules of predetermined spatial frequency formed thereon. The apparatus is structured...
4426131 Replaceable diffraction gratings for cooled laser optics  
An improved optical diffraction grating for high power laser systems is described which comprises a disk or wafer of suitable material, such a single crystal silicon, having on one side thereof the...
4426130 Semi-thick transmissive and reflective sinusoidal phase grating structures  
Markedly increased optical efficiency for a first diffraction order of incident wave energy, such as light, is derived from a layer of transparent material having effectively two serially spaced...
4416505 Method for making holographic optical elements with high diffraction efficiencies  
Production quantities of a multi-element holographic scanner disc are made by optically replicating a silver halide master disc one element at a time in a dichromated gelatin film. The dichromated...
4410237 Method and apparatus for shaping electromagnetic beams  
The intensity profile of a beam of electromagnetic waves such as a laser beam is shaped by means of a diffraction grating and/or prism in the beam path. In one embodiment, beams exhibiting Gaussian...
4384210 Spatial low pass filter for range finding systems  
A low pass filter for an auto focus camera system to deflect light from the main lens by a controlled angular amount and thus suppress high frequency components in the signal.
4361403 Multiple wavelength instrument for measurement of particle size distributions  
A method for measurement of the size distribution of particles suspended in a gas or in a liquid. The particle suspension is illuminated by a collimated beam of colored light, which is produced by...
4360586 Spatial period division exposing  
Soft carbon-K X-rays (38) expose a PMMA photoresist (31) on an oxide layer (32) of a silicon substrate (33) through a parent mask (30) separated a distance S from the resist by a spacer (34) with...
4360251 Display device and method utilizing phase gratings  
An array of picture elements is disclosed for providing a display having selectivitely light or dark areas. The array includes light valves each comprising a pair of light transmissive elements...
4327966 Variable attenuator for laser radiation  
The invention relates to a variable attenuator having two phase gratings (1 and 2) with rectangular grooves. In a first embodiment of the present invention the gratings are slidably mounted (10,...
4289371 Optical scanner using plane linear diffraction gratings on a rotating spinner  
An optical scanning system including a spinner containing at least one plane linear diffraction grating. As the spinner is rotated, a plane reconstruction wave of wavelength λ r is directed onto...
4277138 Diffraction grating and system for the formation of color components  
A device for spacially separating specific spectral regions, preferably of color components from a wideband spectrum which is actively and/or passively radiated by objects. The spectral regions, or...
4269915 Information carrier original for zero order diffraction projection  
An original of an information carrier, and a process of making the carrier is disclosed in which the carrier comprises a layer of carrier material to which a layer of recording material has been...
4257673 Device for coupling at least three light guides  
The invention provides a coupling device for monochromatic optical signals based on the amplitude division method. The optical signal emerging from one light guide is divided by means of one or...
4255019 Diffractive color filter  
A diffractive color filter, comprised of proximately disposed diffraction grating and lenticular lens structures, which may be embossed on plastic sheet, cooperates with an imaging lens to produce...
4208637 Tunable optical device  
A tunable optical device is produced by forming in the surface of a substrate a fan-shaped grating of continuously varying period by means of a holographic technique using a photoresist and twisted...
4191473 Method of and apparatus for measuring the absolute wavelength of a source of unknown frequency radiation  
The invention constitutes a method of and apparatus for measuring the absolute wavelength of a source of unknown frequency radiation through directing radiant energy of known frequency against a...
4184746 Transmissive diffractive phase-grating  
A transmissive diffractive phase-grating which substantially nulls the zeroth order of the light-source or substantially nulls the undiffracted transmission of generally all frequencies of visible...
4178611 Optical low pass filter  
An optical low pass filter adapted for use in a single or double tube color television camera provided with an optical system including a color encoding filter for obtaining color or chrominance...
4129382 Method and apparatus for storing and reading authenticating information  
A method and apparatus are provided for storing and reading authenticating information which is recorded on a carrier comprising at least one diffraction screen for modifying the path of a beam...
Matches 651 - 700 out of 744 < 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 >