Abstract: A glass article having a solar control coating is disclosed for use in producing heat reducing glass for architectural windows. The coated article includes a glass substrate, an iridescence-suppressing interlayer deposited on and adhering to the surface of the glass substrate. At least a first transparent coating deposited on and adhering to the surface of the iridescence-suppressing coating and at least a second transparent coating deposited on and adhering to the surface of the first transparent coating. The first transparent coating and the second transparent coating have a difference in refractive indices in the near infrared region greater than a difference in the refractive indices in the visible region. The use of the article in architectural glazing results in a glazing that rejects solar energy in the near infrared region while permitting the transmittance of a high degree of visible light.

Abstract: An optical filter includes a dielectric layer formed within a resonant optical cavity, with the dielectric layer having formed therein a sub-wavelength periodic structure to define, at least in part, a wavelength for transmission of light through the resonant optical cavity. The sub-wavelength periodic structure can be formed either by removing material from the dielectric layer (e.g. by etching through an electron-beam defined mask), or by altering the composition of the layer (e.g. by ion implantation). Different portions of the dielectric layer can be patterned to form one or more optical interference filter elements having different light transmission wavelengths so that the optical filter can filter incident light according to wavelength and/or polarization. For some embodiments, the optical filter can include a detector element in optical alignment with each optical interference filter element to quantify or measure the filtered light for analysis thereof.

Abstract: An infrared detector including a sensor which provides an output signal responsive to infrared radiation incident on a face thereof, and a diffractive optical element which directs a substantial portion of incident visible radiation away from the sensor and which has substantially no diffractive effect on incident infrared radiation.

Abstract: A multi-fold optical magnifier includes a prism with four reflecting surfaces positioned to direct light from an inlet to an outlet, and a lens positioned adjacent the prism outlet to receive light from the prism. An aspheric surface of the lens is in the light path for aberration correction and diffractive optical elements formed on the prism and lens are positioned in the light path to provide further aberration correction. The prism and lens angularly magnify an image source at the prism inlet by greater than ten. The total distance, orthogonal to the source plane, between the prism inlet and the lens outlet is 10 to 15 millimeters.

Abstract: In an optical apparatus, such as a semiconducter optical amplifier device and an optical filtering apparatus, there are provided an optical amplifier device, a detector and a controller. The optical amplifier device has such a structure that exhibits a both-end voltage change at an optical amplification time of an input light. The detector detects the both-end voltage change, and the controller performs a predetermined control of a portion other than the optical amplifier device, such as another optical amplifier portion and a tunable band pass filter portion.

Abstract: A color separation microlens is fabricated to be a single micro-optical element made up of a color separation grating integrated with a refractive lens. The color separation microlens separates the spectrum into distinct color spots and focuses these spots to a common plane. The spots fall at the locations of the different diffraction orders of the grating. The color separation is done by the grating, and the focusing is done by the lens. The color separation microlens can be fabricated as a monolithically integrated element (an element in which the grating and the lens are combined to a single surface) and can also be fabricated as a dual-sided thin wafer (a wafer in which the grating is on one side and the lens is on the other).

Abstract: A filter has a preselected attenuation/wavelength characteristic, in which spatially separated parts of the filter attenuate different wavelengths. The spatially-separated parts have different attenuation characteristics to attenuate different wavelengths in a predetermined manner to provide a selected attenuation/wavelength characteristic. In one arrangement an interference type filter includes a grating, the pitch of which varies spatially. In one instance, the structure to determine the proportion of radiation subject to interference includes a grating of spatially-varying effectiveness, but alternatively it may include an attenuation filter, the attenuation effect of the attenuation layer varying spatially. In another arrangement, the filter may include structure to separate received radiation into a spatially-disposed spectrum, and to attenuate different parts of the spatially-disposed spectrum in such a manner as to provide the selected attenuation/wavelength characteristic.

Abstract: A holographic filter for protection from radiation, notably laser radiation. At least one support is covered with at least two holograms. Each hologram is constituted by a stack of strata. The holograms are fixed to each other by an optical bonder associated with a selective absorbent material.

Abstract: A photographing apparatus comprising an optical low-pass filter of phase grating type in which a plurality of prism portions, convex or concave in cross section, are arrayed in succession at a predetermined pitch, the arrangement being such that the aperture center or the optical axis of a photo taking lens is located substantially at an apex position of a concave or convex portion which is formed by a prism portion and its adjacent prism portion.

Abstract: A reflective element 26, such as a Bragg grating, impressed in an optical fiber 24, has a reflection wavelength which is tuned by compressing the grating 26. Because an optical fiber is a much stronger under compression than in tension, the grating 26 is tunable over a much broader range than conventional tension/stretching techniques.

Abstract: A flexible rejection filter removes coherent radiation from an incoming beam of light. The filter includes a beamsplitter for dividing the transmitted portion into first and second beams. A photorefractive crystal in the paths of the first and second beams couples coherent radiation from the first beam to the second beam. A focal plane detector follows the crystal in the path of the first beam for sensing the incoherent radiation in the first beam, while a beam dump follows the crystal in the path of the second beam for absorbing the coherent radiation of the second beam. Other filter configurations can utilize contradirectional energy coupling or resonator structures in conjunction with photorefractive media.

Abstract: Spatially variable nonlinear optical thresholding in the Fourier plane reduces signal-dependent noise, such as scalar multiplicative noise. Coherent artifact noise reduction by a factor of four is attained using deamplifying photorefractive two-beam coupling. A variable light transmittance threshold across a spatially thresholded light modulating element such as a photorefractive crystal is utilized for this purpose.

Abstract: The optical device can examine a spectrum at low resolution and subsequently choose a portion of that spectrum to be examined at higher resolution, using a single detector array for both spectra. The latter spectrum can be chosen to be arbitrarily anywhere within the low resolution spectrum. The device comprises a source of input light, a wedged shaped dispersive device, a first reflective mirror, a second reflective mirror, a RF generator connected to the dispersive device, and a detector array. In operation, the dispersive device provides a low dispersion spectrum in the zero order light when the source of light is impinged upon it. When the RF generator is turned on, a second spectrum which is diffracted is obtained. This will be the high resolution spectrum. By operating near 100% diffraction efficiency, it is possible to switch from one spectrum to the other. By adjusting the RF frequency the band center of the high resolution spectrum can be varied to fall anywhere within the low resolution spectrum.

Abstract: Method and apparatus for creating discrete phase optical elements. An arbitrary phase structure is represented by color encoding to produce a color encoded mask. Thereafter, a photo-sensitive substrate is exposed to broad spectrum light transmitted through or reflected from the mask to create the discrete phase structure in the substrate. In preferred embodiments, the exposed substrate is developed and bleached (if necessary) to remove pigmentation to produce highly efficient multiple level phase structures for optical applications. The color encoded mask is produced by a computer-driven color printer resulting in very fast turnaround times.

Abstract: In order to improve an attenuator for a laser beam of a high-power laser comprising a diffraction element which in an attenuating position extends in a section oriented transversely to a beam direction of the laser beam and is irradiated by the laser beam such that it will also withstand the laser beams of high-power lasers, it is proposed that the diffraction element extend beyond the laser beam in the direction transverse to the beam direction so only a partial region of the diffraction element is irradiated by the laser beam and that the diffraction element be continuously moveable in this direction by a drive such that the laser beam irradiates constantly changing partial regions of the diffraction element.

Abstract: The electronic imaging apparatus comprises an imaging lens system for forming an image of an object at magnifications different between an x-z section and y-z section when the object is placed on a z-axis, an imaging optical system, an image sensor having a photoelectric converting surface substantially perpendicular to the z-axis for receiving the image of the object, and a video signal processing circuit capable of changing a difference in expansion/contraction ratio between a scanning direction and the direction perpendicular thereto for reproducing an image of object on the basis of output signals from the image sensor and is capable of generating video signals for displaying an image substantially similar to the object. This electronic imaging apparatus permits obtaining a very clear reproduced image which is substantially similar to the object.

Abstract: A method for generating holographic optical elements such as power spectrum filters is carried out using a printer and a computer. A signal function is input into the computer and traced by the printer to produce a power spectrum envelope of the signal function. The power spectrum is then filled in with a grating pattern whose line spacing is determined by the desired diffraction of coherent radiation beams used to interrogate the optical element.