Abstract: A method for forming a structure comprising multiple parallel surfaces having a precise separation is disclosed. Precise separation and parallelism of the surfaces is achieved through the use of an adhesive mixture that comprises a plurality of spacers having a dimension substantially equal to the desired separation.

Abstract: An optical displacement sensor is disclosed comprising a beam splitter having two optically coupled and mechanically coupled optically resonant cavities. The respective cavity lengths of the optically resonant cavities are functions of an environmental stimulus. By virtue of the optically coupled optically resonant cavities, the output of the beam splitter is less sensitive to input wavelength variation yet retains high sensitivity to the environmental stimulus.

Abstract: An optical displacement sensor is disclosed that provides a optical displacement sensor that includes a optically-resonant cavity tuned to an operating wavelength without some of the disadvantages for doing so in the prior art. An embodiment of the present invention tunes an operating wavelength used with a Fabry-Perot interferometer to develop a desired relationship between the wavelength and the Fabry-Perot interferometer's initial cavity length.

Abstract: An optical displacement sensor for sensing an environmental stimulus is disclosed. The optical displacement sensor exhibits an optical design that has suppressed back reflection and improved alignment tolerance between its optical components. The sensor is based on an optically resonant cavity whose cavity length is affected by the environmental stimulus. An embodiment of the present invention utilizes a lens to redirect a first light signal toward an optically resonant cavity such that the light is incident on the cavity at a non-normal angle of incidence.

Abstract: An accelerometer based on an optical displacement sensor is disclosed. An embodiment of the present invention directs a light beam toward an optically resonant cavity and detects both the reflected and transmitted optical beams that result from interaction with the optically resonant cavity. The optically resonant cavity has a cavity length that is based on the position of a proof mass that moves in response to an acceleration.

Abstract: An optical displacement sensor is disclosed that provides a optical displacement sensor that includes a optically-resonant cavity tuned to an operating wavelength without some of the disadvantages for doing so in the prior art. An embodiment of the present invention tunes an operating wavelength used with a Fabry-Perot interferometer to develop a desired relationship between the wavelength and the Fabry-Perot interferometer's initial cavity length.

Abstract: An optical displacement sensor is disclosed that provides a optical displacement sensor that includes a optically-resonant cavity tuned to an operating wavelength without some of the disadvantages for doing so in the prior art. An embodiment of the present invention tunes an operating wavelength used with a Fabry-Perot interferometer to develop a desired relationship between the wavelength and the Fabry-Perot interferometer's initial cavity length.

Abstract: An optical displacement sensor is disclosed that provides a high signal-to-noise ratio output signal without some of the disadvantages for doing so in the prior art. An embodiment of the present invention directs a light beam toward a Fabry-Perot interferometer and detects both the reflected and transmitted optical beams that result from interaction with the Fabry-Perot interferometer. Signal processing techniques are applied to signals based on both the reflected and transmitted beams, resulting in higher signal strength and/or reduced noise in the resulting output signal.

Abstract: A nanomechanical near-field grating device is disclosed which includes two sub-gratings vertically spaced by a distance less than or equal to an operating wavelength. Each sub-grating includes a plurality of line-elements spaced apart by a distance less than or equal to the operating wavelength. A light source (e.g., a VCSEL or LED) can provide light at the operating wavelength for operation of the device. The device can operate as an active grating, with the intensity of a reflected or transmitted portion of the light varying as the relative positions of the sub-gratings are controlled by an actuator. The device can also operate as a passive grating, with the relative positions of the sub-gratings changing in response to an environmentally-induced force due to acceleration, impact, shock, vibration, gravity, etc.

Abstract: An apparatus and method for discriminating a directional component of a propagating pressure wave using an array of operatively-coupled displacement sensors are disclosed. In accordance with the illustrative embodiment, each displacement sensor in the array comprises two parallel layers, at least one of which is movable. The output signal of each displacement sensor is based on the separation of the layers. The displacement sensors are operatively-coupled through a compressible fluid such that the response of one of the sensors to an input can cause an output signal in at least one of the other sensors. The operative-coupling of the displacement sensors amplifies relative phase information between their respective output signals, which results in improved directionality. Some embodiments of the present invention are particularly well-suited for use in microphones.

Abstract: An apparatus and method for detecting multiple beams from a beamsplitter is disclosed. Some embodiments of the present invention are particularly well-suited for use in microphones, high-sensitivity pressure sensors, vibration sensors, and accelerometer applications. Some embodiments of the present invention generate a differential electrical output signal that is based on multiple detected optical signals. The differential output signal is generated in response to an environmental stimulus, such as a pressure differential or incident acoustic energy. In accordance with the illustrative embodiment, an optical displacement sensor redirects the transmitted beam back through the optically-resonant cavity with an angular offset. Due to the angular offset, the redirected beam (i.e., retransmitted beam) transits the cavity with an intra-cavity path length that corresponds to substantially full transmittance of the retransmitted beam in the absence of the environmental stimulus.

Abstract: A tunable nanomechanical near-field grating is disclosed which is capable of varying the intensity of a diffraction mode of an optical output signal. The tunable nanomechanical near-field grating includes two sub-gratings each having line-elements with width and thickness less than the operating wavelength of light with which the grating interacts. Lateral apertures in the two sub-gratings are formed from the space between one line-element of the first sub-grating and at least one line-element of the second sub-grating. One of the sub-gratings is capable of motion such that at least one of aperture width and aperture depth changes, causing a perturbation to the near-field intensity distribution of the tunable nanomechanical near-field grating and a corresponding change to the far-field emission of thereof.