Abstract: The present invention is a deployable climate blanket system for regulating temperature of a water surface, including two or more climate blanket secured one to another, each blanket configured with an interior air-filled cavity and a plurality of weights for maintaining the system into a desired position. When use of the blankets is no longer desired, the blankets can be lowered beneath the water surface so as not to interfere with boat traffic or other surface use of the water.

Abstract: An electronically agile spectro-polarimetric imager is described in which an acousto-optic tunable spectral filter (AOTF) is located in series with an electronically tunable optical phase modulation plate such that incident radiation will pass through the modulation plate and the AOTF in sequence. This system makes it possible to perform both spectral analysis, complex polarization analysis and object discrimination at video-rates of incident radiation from complex target scenes according to the spectral content and polarization state of the radiation reflected or emitted from the objects within the scene, regardless of the polarization state of the incident radiation. Embodiments for analyzing incident radiation of various wavelengths are provided.

Abstract: A method and apparatus for increasing the angular aperture of an acousto-optic dispersive light filter in which acoustic frequencies of differing frequencies are launched into a crystal at differing angles to each other. Input light phase matches with corresponding ones of the acoustic frequencies so that the angular aperture is enlarged.

Abstract: An acousto-optic tunable filter configuration and a method for the operation thereof, whereby the tuning range is extended. A non-collinear acousto-optic tunable filter crystal has a first transducer bonded to one transducer face of the crystal and a single transducer bonded on the opposite crystal face which crystal face is cut so as to be parallel to the first transducer. The first transducer operates at a center frequency f.sub.1 and the second transducer operates at a center frequency f.sub.2. By launching acoustic waves having a center frequency f.sub.1 into the crystal from the crystal's first side acoustic waves propagate in a first direction such that the interaction of the acoustic wave with the light results in the absorption of a phonon. Acoustic waves having a center frequency f.sub.

Abstract: The invention is directed to an acousto-optic dispersive light analyzer (AODLF) which is an electronically adjustable spectroscopic device capable of instantaneously monitoring many wavelengths with a fixed drive frequency. The AODLF has about a one octave range, whose center is selected by changing the RF. The resolution of the AODLF in the infrared is several thousand, and it is electronically adjustable. The acousto-optic device according to this invention is particularly useful for the detection and analysis of short light pulses. An additional capability of the AODLF is its operation in a derivative mode for enhanced SNR of coherence detection in the presence of a high incoherent background by imposing a very small frequency modulation on the RF applied to the AODLF. Then by phase locking each of the detector element signals at first the fundamental and then the first harmonic of the FM, the first and second spectrum derivatives of each resolution element can be observed.

Abstract: The invention is directed to an acousto-optic dispersive light analyzer (AODLF) which is an electronically adjustable spectroscopic device capable of instantaneously monitoring many wavelengths with a fixed drive frequency. The AODLF has about a one octave range, whose center is selected by changing the RF. The resolution of the AODLF in the infrared is several thousand, and it is electronically adjustable. The acousto-optic device according to this invention is particularly useful for the detection and analysis of short light pulses.

Abstract: An improved acousto-optic tunable filter infrared analyzer system useable in a variety of industrial and commercial combustion control applications includes an acousto-optic tunable filter having a crystalline material selected from the group consisting of mercurous chloride, mercurous bromide and mercurous iodide. Selectively polarized infrared radiation is passed at a predetermined plane of incidence to the crystal axis, which plane contains both the (110) and (001) axes. The system relies upon a narrow band pass tunable acousto-optic filter which is selectively tuned by predetermined rf frequency signals to selectively transmit the narrow band pass of interest which corresponds to a specific molecular species for identification and analysis. The system includes a microcomputer and associated memory function to measure and compare detected signals from an infrared detector which converts the filtered infrared signal to an electrical signal.

Abstract: The invention relates to a method and an apparatus for enlarging the spectral range of an acousto-optic tunable filter by extending the operation of the transducer structure to its third harmonic. The transducer structure consists of a plurality of individual transducer elements in electrical communication through a switching network which modifies the total capacitance of the transducer structure to provide a satisfactory impedance match at both the fundamental and the third harmonic.

Abstract: A transducer plate having at least two mounting zones separated by a transverse groove of a depth greater than the desired thickness of the transducer plate obtained after polishing the mounted transducer plate, and a method for mounting the transducer plate to an optical medium to form an acousto-optic device are disclosed.

Abstract: The invention is a method and apparatus for the refraction of an optical ray from a first focal point to at least one other focal point. The method includes the steps of passing the optical ray through an optical medium to establish a first focal point and then launching acoustic waves into the optical medium to induce at least one half standing acoustic wave within the optical medium. The induced refractive index gradient deviates the optical ray from the first focal point to at least one other focal point. This method of induced refraction can be utilized as a chopper in one embodiment and as a high energy dissipation means in an alternative embodiment.

Abstract: Method and apparatus is described for interacting bulk acoustic waves with an optical waveguide on a common substrate to switch, modulate or deflect guided light at a very high speed. A direct application lies in a monolithic optical analog-to-digital converter. To this effect, a plurality of transducer elements regularly spaced in an array across the optical waveguide are controlled with constant or variable phase shift along a slope, thus causing deflection of the guided light in a fashion analog to phased-array radar technique. A fully integrated monolithic device is constructed combining the bulk acoustic wave generating and optical waveguide functions.

Abstract: The self-generating thermal radiation properties of an optical fiber element are employed to determine the temperature, location and length of a hot spot, or region, of an object.

Abstract: Method and apparatus is described for interacting bulk acoustic waves with an optical waveguide on a common substrate to switch, modulate or deflect guided light at a very high speed. A direct application lies in a monolithic optical analog-to-digital converter. To this effect, a plurality of transducer elements regularly spaced in an array across the optical waveguide are controlled with constant or variable phase shift along a slope, thus causing deflection of the guided light in a fashion analog to phased-array radar technique. A fully integrated monolithic device is constructed combining the bulk acoustic wave generating and optical waveguide functions.

Abstract: An improved optical fiber temperature sensor includes at least one optical fiber light conductor including an optical fiber core, cladding material around the core, and a jacket surrounding the core and cladding material. The core exhibits an evanescent field which extends through the cladding material into the jacket in a first selected range of optical wavelengths. Light attenuation in the conductor below a first temperature range is less than light attenuation above the temperature range. By applying light to the conductor at a frequency with the selected optical wavelength range and detecting the light passed through the conductor, an approximate temperature within the temperature range can be sensed. A more accurate temperature can be sensed by using either two optical fiber light conductors having different optical properties or by using two light frequencies with a single conductor which responds differently to the two frequencies.

Abstract: An amorphous film of As.sub.2 S.sub.5 on a substrate is disclosed for use in various optical applications. The film can be shaped as a lens to focus light. By mounting an acoustic transducer on the film to produce surface or bulk acoustic waves light moving in the film can be deflected or modulated respectively. The film can also be used in anti-reflective, high reflectivity, and photoconductive coatings.

Abstract: An arrangement for monitoring a particular condition, specifically temperature in a preferred embodiment, is disclosed herein and includes a sensor in the form of at least one optical fiber. This optical fiber cooperates with a light source and detector for sensing changes in the temperature being monitored and is accomplished by selecting the fiber such that the amount of light which passes through it varies with changes in temperature.

Abstract: Acoustic imaging system wherein signals from a target of interest impinge upon a set of receiving transducers. The transducer signals are processed and form the input signals to a transparent delay line through which is projected coherent light from a laser. Suitable optics and detectors are positioned relative to the projected laser beam so as to produce an output signal that is applied to a CRT to display a range profile or contour map of the target area.

Abstract: Single crystals of Tl.sub.3 TaS.sub.4 and Tl.sub.3 TaSe.sub.4 are disclosed which have useful acousto-optical properties, including low acoustic velocities and high acousto-optical figures of merit. They are used in acousto-optical devices such as a display device, a laser modulator, a non-collinear tunable filter, an acousto-optical delay line, and an acousto-optical waveguide modulator.

Abstract: An optical waveguide modulator is disclosed which uses single crystals of TlGaSe.sub.2 or TlInS.sub.2. The optical waveguide modulator is used to impress a signal upon a light beam traveling in a waveguide. Monochromatic light is guided along a thin plate of the crystal. Acoustic waves are generated which move across the thickness of the crystal, modulating the light. The frequency, polarization, or mode of the light can be modulated by the acoustic waves.