Abstract: An electric lamp includes a first light source and a second light source and power circuitry configured to selectively energize the first light source and the second light source. The first light source is configured to produce light that is substantially free of wavelengths below about 530 nanometers, and the second light source is configured to product light having wavelengths of less than about 530 nanometers. The electric lamp is configured to produce white or near-white light in a variety of color temperatures, while retaining good color rendering index.

Abstract: An electric lamp includes a first light source and a second light source and power circuitry configured to selectively energize the first light source and the second light source. The first light source is configured to produce light that is substantially free of wavelengths below about 530 nanometers, and the second light source is configured to product light having wavelengths of less than about 530 nanometers. The electric lamp is configured to produce white or near-white light in a variety of color temperatures, while retaining good color rendering index.

Abstract: A runway and taxiway lighting system (of FIG. 1). The system (100) includes a housing (105) as part of a light assembly (102), which light assembly (102) includes a light source (120) for emitting light (123), and a light pipe (126). The light pipe (126) has a first end (124) in close association with the light source (120) for coupling the light (123) thereinto, and a second end (128) from which the light (123) is dispersed. The system (100) also includes a power source encased in a power box (108), and operatively connected to the light assembly (120) for providing power thereto.

Abstract: A runway and taxiway lighting system (of FIG. 1). The system (100) includes a housing (105) as part of a light assembly (102), which light assembly (102) includes a light source (120) for emitting light (123), and a light pipe (126). The light pipe (126) has a first end (124) in close association with the light source (120) for coupling the light (123) thereinto, and a second end (128) from which the light (123) is dispersed. The system (100) also includes a power source encased in a power box (108), and operatively connected to the light assembly (120) for providing power thereto.

Abstract: According to the present invention, there is provided an optical sensor capable of detecting, identifying or measuring a property of a solid, liquid or gas which is in contact with its measuring surface. The preferred sensor comprises an optically transparent sensing element with at least one surface, an optical energy source, means for conducting optical energy from the source to the sensing element at a specific, precisely determined angle and a photodetector. The measuring surface of the sensing element forms an interface with the substance to be measured. Optical energy is partially reflected from the interface formed at the planar surface of the transparent element toward the photodetector. It has been discovered that the resulting signal from the photodetector is proportional to the refractive index of the medium covering the outer surface of the transparent element.

Abstract: Light from a light source (10) is transmitted along an optical fiber (12) through a sensor (14) to opto-electronics (16). The sensor includes a cantilevered beam (20) that flexes in response to acceleration causing its free end (26) to move. Light from the optical fiber (12) is transmitted along an optical fiber to a terminal end (30) thereof and across a gap (34). Light transmitted across the gap is returned to the optical fiber by a mirror (FIG. 2 ) or received by a free end (36) of a second optical fiber (FIG. 1) and conveyed to the opto-electronics. The beam member is configured with an appropriate stiffness that under acceleration, the beam flexes moving its free end sufficiently to change measurably through transmission of light across the gap to the opto-electronics.

Abstract: An optical fiber (12) extends from a light source (10) along a beam (16) of a sensor (18). The optical fiber terminates in a free end adjacent a free end of the beam and generally opposite to a fixed free end of a target, such as a second optical fiber (20). Light is transmitted across a gap between the first and second optical fibers in accordance with the degree of alignment thereof. The beam (16) has at least two portions (38, 40) extending longitudinally therealong. Each of the beam portions is constructed of a material that changes longitudinal dimension to a different degree than the other in response to the sensed condition. In this manner, the sensed condition causes the beam to bend, altering the degree of alignment between the optical fiber free ends in response to the sensed condition.

Abstract: Light from source (10) is transmitted along an optical fiber (12) to a free end (20). Light emitted from the optical fiber free end is transmitted to a target (22), such as the free end of a second optical fiber (16). An opto-electric transducer (18) provides an output that varies in accordance with the intensity of received light. Relative alignment between the optical fiber free end and the target is controlled by movement of a cantilever beam member (30). The cantilever beam member is a strip of ferromagnetic material (40) extending therealong. A second elongated ferromagnetic strip (42) is mounted closely adjacent but spaced from a free end (36) of the cantilever beam member defining a flux gap (44) therebetween. As magnetic flux flows through the ferromagnetic strips, the beam member free end is deflected in proportion to the strength of the magnetic field.

Abstract: A first optical fiber coil (A) is disposed adjacent one end of a housing (40). The housing defines an interior reservoir (44) which contains a material (B) having substantial mass, preferably a dense fluid. A second optical fiber coil (C) is mounted to the housing but isolated from pressure or force exerted by the mass material during acceleration. Phase coherent light is transmitted from the laser (10) through the two optical fiber coils. Under acceleration, the pressure or force on the first optical fiber coil causes a corresponding length change. The change in length causes a phase shift of the phase coherent light travelling the first optical fiber coil relative to the light which has travelled the second optical fiber coil. A signal processor (36) translates the phase shift into an indication of acceleration for display on an acceleration indicator (38).

Abstract: The apparatus according to the invention is all-fiber optic device that produces an output indicative of the gradient of an acoustic wave in water. The device comprises a neutrally buoyant body having a relatively rigid outer case. When it is submerged in water, the motion of the case is the same as that of a water particle in the same vicinity. A fiber optic linear accelerometer produces a signal proportional to the component of acceleration.

Abstract: An optical sound source signature transducer system for use in marine seismic exploration in which coherent radiation from a laser is coupled to unequal length optical paths exposed to modulation by the acoustic energy wave generated by the sound source. The reflected beams from the paths are crosscoupled to generate interference fringes in two output beams out of phase with each other. The fringes in one output beam are counted in an up/down counter to determine the magnitude of the pressure as a function of time. The direction of the pressure change is determined by examination of the phase relationship between the fringes in the output beams. Peaks and valleys in the pressure are detected as phase reversals between the fringes in the output beams be detecting the beginning and end of a fringe in one beam without detecting the beginning or end of a fringe in the other beam therebetween.

Abstract: First and second coils (A, B) of optical fibers are disposed adjacent opposite ends of a housing (40). The housing defines an interior reservoir which contains a material (C) having substantial mass. Preferably, the material is a dense fluid such as mercury. Phase coherent light from a laser (10) is transmitted through the first and second optical fiber coils. The phase coherent light passing through the first and second coils is combined by an optical coupler (22). Under acceleration, the pressure to which the mercury subjects the two fiber optic coils varies by a pressure differential that is proportional to acceleration. The pressure differential causes a corresponding elongation and contraction of the optical fiber lengths which, in turn, causes a corresponding optical phase shift. The optical phase shift is detected interferometrically providing optical intensity changes.

Abstract: The invention relates to a technique for detecting electric fields by modulating the phase of an optical beam. A length of optical fiber is jacketed with or attached to piezoelectric material that is poled perpendicular to the length of the fiber. An electric field is applied across the piezoelectric element, i.e. in the direction of poling, resulting in a change in the element thickness and a change in the axial dimension, which, in turn, changes the length of the optical fiber. The change in fiber length is accompanied by a smaller change in the refractive index of the fiber. The result is a shift in the optical phase.

Abstract: This invention relates to an optical fiber acoustical sensor for sensing acoustic vibrations and in combination with an incoherent or coherent source of light such as a LED or a laser and a photo detector to determine the frequency and amplitude of the sound pressure variations. The invention consists of an element of optical fiber without cladding surrounded by a liquid or plastic potting material permeable to sound pressure and having an index of refraction slightly less than the fiber. The intensity of a light beam transmitted by means of fiber optic waveguides, single or multi-mode, from a source of light through the sensor to a photo detector varies with the variation of sound pressure to which the sensor is subjected. If the sensor is in water, the transmitted light intensity varies with the acoustical pressure in the water because the changes in liquid or plastic index of refraction changes with the sound pressure.

Abstract: An optical fiber acoustical sensor for detecting sound waves in a fluid mum. An optical fiber coil through which a light beam is transmitted is placed in a fluid medium. A sound wave propagating through the fluid medium and incident on the optical fiber coil changes the index of refraction of the optical fiber at the area of incidence. The index change causes a phase shift in the transmitted light which is detectable to denote the presence of the sound wave.