Abstract: A method and an apparatus for retrofit electrolization of seawater for production of halogen biocides in situ. A method for effecting an in situ generation of biocide as an aid in anti-biofouling of a device disposed in a volume of salt water includes a) associating a cathode electrode to the device; b) associating an anode electrode to the device with the anode electrode spaced apart from the cathode electrode; and c) hydrolyzing one or more components in the volume of salt water to generate a halogen biocide at the anode electrode with the biocide flowing from the anode electrode away from the cathode electrode as a biocide film, the film responsive to a physical arrangement of the associations of the electrodes with the device.

Abstract: A method and an apparatus for retrofit hydrolization of seawater for production of halogen biocides in situ. A method for effecting an in situ generation of biocide as an aid in anti-biofouling of a device disposed in a volume of salt water includes a) associating a cathode electrode to the device; b) associating an anode electrode to the device with the anode electrode spaced apart from the cathode electrode; and c) hydrolyzing one or more components in the volume of salt water to generate a halogen biocide at the anode electrode with the biocide flowing from the anode electrode away from the cathode electrode as a biocide film, the film responsive to a physical arrangement of the associations of the electrodes with the device.

Abstract: A method and an apparatus for retrofit hydrolization of seawater for production of halogen biocides in situ. A method for effecting an in situ generation of biocide as an aid in anti-biofouling of a device disposed in a volume of salt water includes a) associating a cathode electrode to the device; b) associating an anode electrode to the device with the anode electrode spaced apart from the cathode electrode; and c) hydrolyzing one or more components in the volume of salt water to generate a halogen biocide at the anode electrode with the biocide flowing from the anode electrode away from the cathode electrode as a biocide film, the film responsive to a physical arrangement of the associations of the electrodes with the device.

Abstract: A method and an apparatus for retrofit hydrolization of seawater for production of halogen biocides in situ. A method for effecting an in situ generation of biocide as an aid in anti-biofouling of a device disposed in a volume of salt water includes a) associating a cathode electrode to the device; b) associating an anode electrode to the device with the anode electrode spaced apart from the cathode electrode; and c) hydrolyzing one or more components in the volume of salt water to generate a halogen biocide at the anode electrode with the biocide flowing from the anode electrode away from the cathode electrode as a biocide film, the film responsive to a physical arrangement of the associations of the electrodes with the device.

Abstract: A critical wavelength refractometer is provided. A broadband light source (413) is optically coupled to a sensor (401), the sensor having at least one sensing surface (407). As the light from the broadband light source passes through the sensor, it undergoes multiple internal reflections against the sensing surface. Due to the index of refraction of the material in contact with the sensing surface, a portion of the light passing through the sensor is reflected while a second portion of the light is transmitted through the sensing surface and into the material. A detector (421) coupled to the sensor measures the spectral intensity of the light that passes completely through the sensor after having undergone the multiple internal reflections against the sensing surface. A microprocessor (423) coupled to the detector determines the critical wavelength based on the spectral intensity measurement, thereby allowing the index of refraction of the material to be determined.

Abstract: A critical wavelength refractometer is provided. A broadband light source (413) is optically coupled to a sensor (401), the sensor having at least one sensing surface (407). As the light from the broadband light source passes through the sensor, it undergoes multiple internal reflections against the sensing surface. Due to the index of refraction of the material in contact with the sensing surface, a portion of the light passing through the sensor is reflected while a second portion of the light is transmitted through the sensing surface and into the material. A detector (421) coupled to the sensor measures the spectral intensity of the light that passes completely through the sensor after having undergone the multiple internal reflections against the sensing surface. A microprocessor (423) coupled to the detector determines the critical wavelength based on the spectral intensity measurement, thereby allowing the index of refraction of the material to be determined.

Abstract: A system comprising a solid-state optical beam regulator, an optical sensing device, and a computer provides for fast, accurate, and automatic tracking, steering, and shaping of an optical beam, such as that required in free-space optical communications. With a CMOS imager as the sensing device and a regulator constructed of a stress-optic glass material whose index of refraction is altered by induced stress, the system can track beam perturbations at frequencies greater than 1 kHz. This performance makes the system suitable for a variety of applications in free-space optical communications.

Abstract: A stress-optic beam scanner and system which includes a stress-optic material selected to permit the scanning of an optical beam on a target typically over a scanning angle of greater than five degrees. The system includes a piezoelectric element controlled by a microprocessor to control the mechanical stress applied to the stress-optic material.

Abstract: A stress-optical phase modulator and modulation system, and method of use of the same is described. The stress-optical phase modulator comprises a source for providing optical beams, a photoelastic optical material, and a means for applying mechanical force to the optical material. The mechanical force so applied creates a uniform stress within the optical material and results in a change in its index of refraction. An optical beam passing through the stressed optical material undergoes a phase change and is recovered as a phase modulated optical beam. Components may be added to the stress-optical phase modulator to produce temperature-compensated and intensity-modulated optical beams.

Abstract: An optical switch which comprises a photoelastic, optically transparent material whose index of refraction is changed by stress and which propagates an optical beam or beams from an inlet window to an outlet window in the material, with the inlet window adapted to receive an optical beam from an optical source and the outlet window adapted to pass an optical beam from the photoelastic material to an optical output receptor, and a receptor means of applying a stress gradient to said photoelastic material to change the index of refraction and hence, the optical path of the optical beam between a normal, unstressed optical beam path and a bent, stressed optical beam path. Optical systems are described in which the optical switch is employed to form optical lenses wherein an optical beam is focused by stress within an optical material, such as a photoelastic cylindrical rod. Optical integrated systems are also described employing the optical switch with optical devices as an optical integrated module.

Abstract: An optical switch which comprises a photoelastic, optically transparent material whose index of refraction is changed by mechanical stress and which propagates an optical beam or beams from an inlet window to an outlet window in the material, with the inlet window adapted to receive an optical beam from an optical source and the outlet window adapted to pass an optical beam from the photoelastic material to an optical output receptor, and a means of applying a stress gradient to said photoelastic material to change the index of refraction and hence, the optical path of the optical beam between a normal, unstressed optical beam path and a bent, stressed optical beam path. Optical systems are described in which the optical switch is employed to receive an optical beam from a source and to switch a beam after passing it through the photoelastic optical material to and from an optical receptor.

Abstract: An optical wave guide sensor which comprises: a broad-band, radiant energy source; an optical wave guide, such as an optical fiber, rectangular slab or thin film, having a guiding interface and an inlet an outlet, the inlet receiving the radiant energy and the wave guide deformable from one part to another of the guide; and a spectral intensity detector at the wave guide outlet to measure the change in the wavelength of the energy critically reflected from the guiding interface on deformation of the wave guide. A method of measuring the deformation of an optical wave guide and/or a parameter causing such deformation, which method comprises: measuring the change in the mode band edge critical wavelength of the first, second or higher mode of the radiant energy throughput of the wave guide as a function of the deformation of the wave guide.

Abstract: Present electrical expendable oceanographic instruments are vulnerable to insulation leaks and electromagnetic interference; they are also unable to measure pressure and the index of refraction. In response to these difficulties a unique combination of optical temperature, pressure, and index of refraction sensors have been developed. These sensors are coupled to an optical fiber transmission link which is contained initially within a probe vehicle and is designed to be unreeled. The remote sensing feature of this combination and technique makes the instrument also suitable for industrial and data - and tele-communications use. The principle of the three sensors is that of optical filters, whose band edges are functions of temperature, pressure, and the index of refraction; this wavelength modulation technique avoids drift and allows the signals from the sensors to be wavelength multiplexed in a single optical fiber, and to be read remotely by a single detector.

Abstract: An index of refraction sensor utilizing a sensor face inclined at the nominal critical angle of an incident beam, refracts or reflects this incident radiation depending upon the wavelength of that radiation and the index of refraction external to it. The refraction sensor apparatus includes a broadband radiant energy source, a radiant energy guidance and collimating means, a prism sensing element interposed in the radiant energy guide, and a detector for continuously detecting the spectral intensities of the broadband radiant energy reflected by the prism sensing element. Advantageously, a single mode optical fiber may be used as the radiant energy guidance and collimating means for directing the broadband radiant energy to the prism and a multimode optical fiber may be used for returning the reflected radiant energy to the detector.