Abstract:
A UV sensor design which virtually eliminates solarization effects on optical components and photodetector and is effective for both broad area and collimated light sources. The sensor design reduces the number of photons striking a unit area of any of the materials in the light path sensitive to UV light to a level which does not produce appreciable solarization over very long periods of time. The UV sensor has as the first optical element in the viewing path a UV transmitting, extremely low solarization window. The back surface of this window is frosted to produce some diffusion of the UV rays. A small metal disc with a very small aperture is the next optical element and reduces the total amount of energy admitted to the optical measurement system. A second frosted UV transmitting, extremely low solarization window further diffuses the light beam passing through the aperture. The UV light from this second window travels toward to two UV filters and is further dispersed to produce low intensity level UV light which impinges on a silicon photodetector.
Abstract:
An apparatus and method for measuring the orientation of a platform by receiving and reading signals from one or more orientation sensors, such as a magnetic compass, using optical interrogation, telemetry, and multiplexing, with the signals passing through a single supply/return optical waveguide.
Abstract:
This invention provides a method for controlling production operations using fiber optic devices. An optical fiber carrying fiber-optic sensors is deployed downhole to provide information about downhole conditions. Parameters related to the chemicals being used for surface treatments are measured in real time and on-line, and these measured parameters are used to control the dosage of chemicals into the surface treatment system. The information is also used to control downhole devices that may be a packer, choke, sliding sleeve, perforating device, flow control valve, completion device, an anchor or any other device. Provision is also made for control of secondary recovery operations online using the downhole sensors to monitor the reservoir conditions. The present invention also provides a method of generating motive power in a wellbore utilizing optical energy. This can be done directly or indirectly, e.g., by first producing electrical energy that is then converted to another form of energy.
Abstract:
A device (1) for securing at least one optical fibre (2; 3; 4; 5) to an optical apparatus (6) is proposed, comprising at least one photo-element (20; 21; 22; 23) mounted on a supporting element (24) and at least one optical fibre (2; 3; 4; 5) which can be connected to the photo-element (20; 21; 22; 23); the securing device (1) comprises at least one transparent part, such that a region of the coupling between the fibre and the photo-element is visible. A securing device (1) is also proposed, comprising a slide (7) provided with at least one slot (8), which assumes a first and a second position; in the first position, the slot (8) is coaxial with a hole (25) in the supporting element (24) and freely houses the optical fibre (2; 3; 4; 5), while in the second position the slot (8) is out of alignment with the hole (25) and exerts on the optical fibre (2; 3; 4; 5) a force which keeps it secured in the hole (25). (FIG. 1).
Abstract:
The present invention relates to a fiber optic sensing device having utility as a roll sensor and/or a pitch sensor. The sensing device comprises at least one optical fiber supported in a structure, a movable mass supported within the structure, and at least one detector for detecting changes in tension in the at least one optical fiber due to movement of the movable mass. In the sensor of the present invention, the optical fiber(s) are the only deformable structures, thus maximizing sensitivity.
Abstract:
Fiber grating environmental measurement systems are comprised of sensors that are configured to respond to changes in moisture or chemical content of the surrounding medium through the action of coatings and plates inducing strain that is measured. These sensors can also be used to monitor the interior of bonds for degradation due to aging, cracking, or chemical attack. Means to multiplex these sensors at high speed and with high sensitivity can be accomplished by using spectral filters placed to correspond to each fiber grating environmental sensor. By forming networks of spectral elements and using wavelength division multiplexing arrays of fiber grating sensors may be processed in a single fiber line allowing distributed high sensitivity, high bandwidth fiber optic grating environmental sensor systems to be realized.
Abstract:
A method and apparatus for monitoring MEMS-based optical switches and cross-connects. A plurality of partial reflectors are introduced into optical paths of the switch for reflecting light transmitted along the optical paths through a transparent substrate of the switch, without disturbing transmission of the light along the optical paths. The reflected light is transmitted through the substrate, which is preferably made of silicon and transparent to wavelengths of light used in DWDM systems. A photodetector array bonded to the underside of the substrate detects the light reflected by the plurality of partial reflectors through the substrate. The light detected by the photodetector array indicates the switching states and functionality of the switch, and can be processed by circuitry associated with the array.
Abstract:
A ribbon-like sensor assembly is described wherein a length of an optical fiber embedded within a similar lengths of a prepreg tow. The fiber is “sandwiched” by two layers of the prepreg tow which are merged to form a single consolidated ribbon. The consolidated ribbon achieving a generally uniform distribution of composite filaments near the embedded fiber such that excess resin does not “pool” around the periphery of the embedded fiber.
Abstract:
An apparatus is provided in which multiple devices are connected in series forming a signal path through which a signal propagates. Each device may have one or more operating frequencies and each operating frequency may generate a corresponding intensity modulation with respect to the signal. For one embodiment, the apparatus includes multiple delay lines through which the signal travels. The length of each delay line is configured to reduce the intensity modulation generated by each device based upon one or more factors including the one or more operating frequencies associated with each device and multiple null orders corresponding to different lengths of the delay lines.
Abstract:
A common reference signal is applied from the same reference signal generating portion to a reference signal input terminal of a signal under test generator and a reference signal input terminal of a sampling signal generator circuit. A sampling frequency is set to the sampling signal generator circuit such that a desired delay time can be obtained relevant to a phase of a signal under test. In the sampling signal generator circuit, the sampling signal having a cycle that corresponds to the sampling frequency is generated based on the common reference signal and the sampling frequency. A repetition cycle of the signal under test and a repetition cycle of the sampling signal are set based on a cycle of the common reference signal so that the repetition cycle of the sampling signal can be set independently of the repetition cycle of the signal under test.