摘要:
Apparatus is provided including a light source, a transducer and a detector, which is capable of detecting applied acoustic signals. The transducer employs first and second ridged members which have parallel rippled surfaces which contact opposite sides of a fiber optic waveguide. Each rippled surface has a different predetermined ripple pitch which provides for variable sensitivity along one dimension of the transducer. Modulation of the position of the ridged members relative to one another by means of applied acoustic signals causes microbend attenuation of light transmitted through the waveguide. The modulation of the light provides an indication of the presence of the acoustic signals. The variation in dimensional sensitivity provided by the transducer allows for a determination of the direction of arrival of the acoustic signals. Appropriate selection of pitch and pitch ratio of the two rippled surfaces provides any desired spatial sensitivity distribution of the hydrophone. A transducer is also disclosed which further incorporates magnetic elements to provide a mechanical prestress bias to the waveguide, thus providing a frictionless and hysteresis-free device.
摘要:
Precisely curved, lightweight and low-cost reflectors for electromagnetic radiation are fabricated by use of a tool and a process in which a blank is planar stretched by uniformly applied isotropic and radially extending forces followed by deformation of the stretched blank to a precisely curved surface.
摘要:
There is disclosed coercivity control and signal generating and detection means comprising a two-dimensional lattice array of dots of magnetically susceptible material in intimate physical contact with the major plane surface of a uniaxially anisotropic ferromagnetic crystal platelet which has its major plane surface cut perpendicularly to the easy axis of magnetization of the crystal so as to be capable of sustaining movable cylindrical magnetic domains therein. Such crystals are used in digital signal translating and memory devices. In the conductor access type of device disclosed herein such domains are moved between predetermined locations in the crystal by electrical drive signals in magnetic field generating conductor loops. By providing the lattice array of dots, each of which is of a size having a maximum dimension which is a small fraction of the minimum diameter of the smallest bubble sustainable in the crystal, it is possible to control the coercivity of the crystal platelet and thereby achieve a greater stability of bubble positioning by the access conductors, a faster switching rate and a greater temperature independence for the necessary biasing field. The lattice array used for coercivity control is also such as to give rise to a signal generated by the bubble being moved with respect to the lattice array which signal may be used to detect the motion of the bubble.
摘要:
Lens barrel (12) has a shoulder (16) therein and a retaining ring to retain lens (20) within the lens barrel. A canted coil spring member (24) is engaged between the retaining ring and lens to resiliently retain the lens in place against thermal cycling, vibration and shock.
摘要:
A multi-dimensional nanometric displacement positioner providing a support apparatus for an optical instrument. The positioner apparatus may nanometrically move an optical holder tube through the combined action of a tapered adjustment shaft and a zig-zag double L-shaped arm, which is connected to an optical holder tube support ring by means of a flexure link. Z-axis displacement is achieved when the inner surface of a manually driven outer drive sleeve contacts a radially directed rod flexurally affixed to a lever; so that, as the lever is pressed against a projecting flange of the holder tube, the tube is translated axially forward.
摘要:
Auxiliary depressions, disposed in the substrate of an integrated optic device which employs geodesic lenses, to adjust the effective focal distance of the geodesic lenses and correct optical aberrations of the geodesic lens system are disclosed. The integrated optic device comprises a substrate, a planar waveguide disposed thereon, a laser source at one end and a detector array at the other end, and geodesic lenses disposed in the substrate. The auxiliary surface depressions are non-spherical, symmetrical about a longitudinal axis and disposed in the substrate between either end of the substrate and the geodesic lens closer to that end. By increasing the path length of light transmitted along the surface layer, these auxiliary depressions allow adjustment of the effective focal distance of the geodesic lenses. Also, non-symmetrical auxiliary surface depressions which correct for optical aberrations in the geodesic lens system are disclosed.
摘要:
An electrically energizable high intensity, radiant energy heater (8) having a general M-shape for providing a pocket (20) for localized high intensity isothermal heating for fusion and fiber processing. The heater is shaped to provide easy access for a fiber (18) at an entry (16) to enable insertion of the fiber into the isothermal high temperature zone in pocket (20). A second re-entrant wall external to the pocket provides radiant shielding and buffers the isothermal heating zone from the cool environment. The heater may be constructed from a ribbon of a resistively heated metal, such as platinum foil.
摘要:
A die (40) for extrusion of optical grade fibers has its hard insert (42) placed under compression within a sleeve (44). Sleeve (44) is provided with a tapered interior surface (50) which matches the tapered exterior surface (48) of the insert (42). A metal lubricating layer (60) is provided between the tapered surfaces. The insert is pressed in to obtain compressive prestressing thereof, and the lubricating metal diffuses at the tapered surfaces to lock the insert in the sleeve.
摘要:
An electromechanical micropositioner for making minute angular and linear translational displacements of an element attached to same. The micropositioner employs electrical control potentiometers, a power source, and a signal source that provides for the type of displacement desired.
摘要:
Apparatus useful in the surgical correction of strabismus comprises a clip (10) attachable to the sclera (52) of an eye, and a dynamometer gauge (12) coupled to the clip to measure torques exerted on the muscle of the eye.