An optical microphone includes: a light source; a first optical divider dividing light from the light source into reference light and measurement light; a second optical divider dividing the measurement light into N measurement light beams; a first emitter emitting the N measurement light beams from different positions toward a predetermined space; a first light receiver receiving the N measurement light beams having propagated through the space; a third optical divider dividing the reference light into N reference light beams; N optical couplers coupling the N measurement light beams with the N reference light beams on a one-to-one basis; N optical detectors receiving N coupled light beams and each detecting interference between the measurement light beam and the reference light beam in the corresponding coupled light beam; and a controller controlling directionality of sound pickup by performing signal processing on N detection signals from the N optical detectors.

Devices, systems and methods for encoding information using optical components are described. An example photonic filtered sampler includes a spectral shaper configured to receive an optical pulse train, a dispersive element positioned to receive an output of the spectral shaper and to expand spectral contents thereof in time, and a modulator configured to receive an output of the dispersive element and a radio frequency (RF) signal, and to produce a modulated output optical signal in accordance with the RF signal. In this configuration, one or more characteristics of the modulated output optical signal is determined based on a spectral shape provided by the spectral shaper and dispersive properties of the dispersive element.

A coherent optical mixer circuit is provided that can measure a phase error without requiring a step of cutting away a delay circuit. Odd-numbered or even-numbered two of four inputs of an 4-input-and-4-output multimode interference circuit are connected to an input mechanism. The four outputs of the multimode interference circuit are all connected to an output mechanism to the exterior. Other two inputs of the multimode interference circuit are connected to two monitor waveguides. One of the monitor waveguide is longer than the other to configure a light delay circuit. The monitor waveguides constituting the light delay circuit are connected to the respective outputs of a 2-branched light splitter. The 2-branched light splitter has an input connected to a monitor light input mechanism from the exterior via a monitor input waveguide.

A coherent optical mixer circuit is provided that can measure a phase error without requiring a step of cutting away a delay circuit. Odd-numbered or even-numbered two of four inputs of an 4-input-and-4-output multimode interference circuit are connected to an input mechanism. The four outputs of the multimode interference circuit are all connected to an output mechanism to the exterior. Other two inputs of the multimode interference circuit are connected to two monitor waveguides. One of the monitor waveguide is longer than the other to configure a light delay circuit. The monitor waveguides constituting the light delay circuit are connected to the respective outputs of a 2-branched light splitter. The 2-branched light splitter has an input connected to a monitor light input mechanism from the exterior via a monitor input waveguide.

An optical transmission apparatus includes a wavelength converter that wavelength-converts input signal light using a nonlinear optical medium to output the converted signal light, a memory that holds first information relating to a wavelength conversion characteristic of the wavelength converter, a communication interface that receives second information relating to a second wavelength conversion characteristic of an adjacent optical transmission apparatus, and a control circuit that determines, using the first information and the second information when the second information is received, an excitation light frequency at which a gain deviation of main signal light subjected to a wavelength conversion is minimized to set the determined excitation light frequency in the wavelength converter.

A wavelength conversion device that converts input signal light having a first frequency into output signal light having a second frequency, includes: a control-light generator that outputs first continuous oscillation light and second continuous oscillation light; and a nonlinear optical medium that cross-phase modulates the input signal light with the first continuous oscillation light and the second continuous oscillation light and generates the output signal light, wherein the control-light generator outputs the first continuous oscillation light and the second continuous oscillation light to have polarized waves in directions orthogonal to each other and have a frequency interval equal to a difference between the first frequency and the second frequency and controls, based on intensity of the output signal light, timings of modulation of phases of the first continuous oscillation light and the second continuous oscillation light to be aligned with each other.

A projector and a wavelength conversion device thereof are provided. The projector includes an illumination system that includes a light source device and a wavelength conversion device. The light source device is configured to provide an excitation beam. The wavelength conversion device is disposed on a transmission path of the excitation beam, and configured to convert the excitation beam into an illumination beam. The wavelength conversion device includes a substrate comprising a first surface, a second surface, and an axis center, a heat-conducting connection structure, a first reflective structure, and a wavelength conversion structure. The heat-conducting connection structure is located between the first surface and a first reflective structure, the first reflective structure is located between the heat-conducting connection structure and a wavelength conversion structure, and the wavelength conversion structure is located on the first reflective structure.

Optical signal receivers and methods are provided that include first and second optical resonators, each of which receives a portion of an arriving optical signal. The first optical resonator is tuned to a carrier wavelength and accumulates resonant optical signal energy whose output is disturbed responsive to a transition in the arriving optical signal. The second optical resonator is detuned from the carrier wavelength but also exhibits a disturbed output responsive to the transition in the arriving optical signal. Detectors detect the output disturbances from the two optical resonators to determine characteristics of the transition in the arriving optical signal.

Optical signal receivers and methods are provided that include first and second optical resonators, each of which receives a portion of an arriving optical signal. The first optical resonator is tuned to a carrier wavelength and accumulates resonant optical signal energy whose output is disturbed responsive to a transition in the arriving optical signal. The second optical resonator is detuned from the carrier wavelength but also exhibits a disturbed output responsive to the transition in the arriving optical signal. Detectors detect the output disturbances from the two optical resonators to determine characteristics of the transition in the arriving optical signal.

An apparatus for interrogating a media to be analyzed, such as an avian egg, is provided. Such an apparatus includes an emitter assembly configured to emit light toward a media. The emitter assembly has a first emitter source configured to emit a first light signal and a second emitter source configured to emit a second light signal. The first and second light signals are transmitted through the media in phase quadrature. A detector assembly is configured to detect the first and second light signals transmitted through the media. The detector assembly is further configured to resolve a relative or absolute amplitude of each of the first and second light signals. A processor is configured to process the detected signal to identify a property of the media using at least one of the relative and absolute amplitudes of the first and second light signals. An associated method is also provided.