摘要:
A quasi-monochromatic light beam carrier for a particular telecommunication channel is likely to experience drift because of age, temperature, or other factors, and may cause the centroid wavelength of the carrier to shift. Temperature adjustments by wavelength lockers to compensate for drift on one channel may affect the performance of other channels. Embodiments of the present invention couple a quasi-monochromatic light beam through a substrate-based grating, diffract the light beam from the edge of the substrate to free space, and detect the light beam from free space at a position detector to determine the centroid wavelength based on a position of the light beam incident on the detector. The diffracted light beam may be reflected within the substrate a number of times prior to exiting the substrate towards the detector.
摘要:
A multiuse system for use with Wireless Display Tags (WDTs) includes, in one or more exemplary arrangements, techniques for automatically maintaining synchronicity between pricing data for a product and advertising, marketing or promotional data associated with that product, and for detecting the proximity and location of a customer within a category of goods displayed within a managed environment. A messaging format suitable for such low power operation among a large number of peers is also disclosed, as is a technique for integrating a plurality of smaller displays to yield a single large display. An access point capable of serving as a communications hub within such a network, while at the same time offering visual and audio surveillance capabilities, is also disclosed.
摘要:
A wavelength reference filter for receiving an input signal and producing a filtered output signal is provided. The operation of the filter is independent of the angle of incidence of the input signal. As a result, the output signal from the filter will maintain its wavelength, even under changes in the direction of propagation of the input signal to the filter. Without such incidence angle independence, a change to the input signal would change the output signal and result in inaccurate device operation. Example incidence angle independent filters may include a single etalon or multiple etalons. In the former example, a signal may traverse a single etalon twice, along paths that have different angular sensitivities relative to the etalon. In the latter example, each etalon may have an equal and opposite angular sensitivity, such that two the etalons have canceling angular sensitivities. All of the filters described and illustrated may be used in various devices, including detectors, laser sources (tunable and otherwise), and transponders.
摘要:
Methods and apparatus for optimizing feedback suppression of optical isolators when used with variable wavelength light sources. The methods comprise positioning an optical isolator in a light beam, and adjusting feedback suppression by the optical isolator according to wavelength of the light beam. Adjusting the feedback suppression may comprise adjusting temperature of the optical isolator or a non-reciprocal rotator associated with the isolator.
摘要:
Method and apparatus for producing a laser output having stimulated Brillouin scattering (SBS) suppression characteristics. An excitation signal is provided to an optical path length adjustment element in an external cavity laser to modulate the optical path length of the cavity. This produces a laser output having a wavelength modulation frequency and line width that are a function of the frequency and amplitude of the excitation signal. Under appropriate modulation frequency and line width combinations, the laser output comprises an optical signal with SBS suppression characteristics, thus enabling a higher power signal to be launched into a fiber link since the SBS suppression characteristics raise the SBS threshold of the link. The optical path length modulation also produces an intensity (amplitude) modulation in the laser output. A detector is employed to produce a feedback signal indicative of the intensity modulation that is used for tuning the laser in accordance with a wavelength locking servo loop.
摘要:
A method comprising forming two or more frames from a first wafer, forming two or more etalons from a second wafer, disposing a resistive thermal device on each of the two or more frames, dicing the first wafer and the second wafer, and bonding each of the frames to a corresponding one of the etalons to form optical subassemblies of optical filters.
摘要:
Briefly, in accordance with one or more embodiments, a thermally controlled optical filter comprises a frame coupled to an etalon where the frame includes a resistive thermal device disposed on the frame to obtain thermal measurements of the etalon during operation. The frame may be generally L-shaped or generally square-shaped. The frame may include a fillet that is generally planar, generally beveled or trapezoidal, or generally circular in shape. A heater may be additionally disposed on the frame. The etalon and frame subassembly may be bonded to a micro hot plate that is capable of heating the etalon to an operational temperature.
摘要:
The present invention is directed to an apparatus and method for improving the power output of a solar energy system. A field level inverter controller is described that may improve the power output of individual solar energy systems in a field of solar energy systems by controlling the inverter voltage applied to strings of solar energy units in a solar energy system connected in parallel to an inverter. An inverter load voltage for an improved power output may be calculated or derived empirically. An algorithm stored in the controller may calculate an improved load voltage for the inverters based on factors such as string geometry, solar movement and shade patterns generated by surrounding structures. Improved power output may be empirically determined by the field level inverter controller when the inverter controller directs an inverter to sweep a range of voltage values until a maximum output is detected.
摘要:
A system may include determination of power delivered to an intended load by a solar collector and determination of a solar tracking error of the solar collector based on the determined power. Some aspects include determination of a servo feedback signal based on the determined power, wherein determination of the solar tracking error includes determination of the solar tracking error based on the servo feedback signal. Determination of the solar tracking error may further include determination of the solar tracking error based on the servo feedback signal and on a relationship between a response of the solar collector and tracking error.