Systems and methods for intrusion detection, including an intrusion detection device configured to send a light source to a retroreflector and receive reflected light from the retroreflector. An alarm is activated if the light source is not detected by the intrusion detection device. The intrusion detection device includes a computing device coupled to a preamplifier, a superregenerative receiver, and a digitizer.

An electronic device includes one or more light sources for emitting light toward a body part of a user and one or more optical sensors for capturing light samples while each light source is turned on and for capturing dark samples while the light source(s) are turned off. A signal produced by the one or more optical sensors is filtered and demodulated produce multiple demodulated signals each associated with a light source. Each signal associated with the light source(s) is analyzed to estimate or determine a physiological parameter of the user.

A total reflection spectroscopic measurement device includes a terahertz wave generation unit, an internal total reflection prism, a detection unit configured to detect the terahertz wave, an electric field vector measurement unit configured to measure an electric field vector of the terahertz wave, and an analysis unit configured to acquire information about an optical constant of the object to be measured. Proportions of S polarization component and P polarization component of the terahertz wave are constant. The analysis unit acquires the information about the optical constant on the basis of a ratio between S polarization component and P polarization component of the measured electric field vector when the object is not arranged on the total reflection surface and a ratio between S polarization component and P polarization component of the measured electric field vector when the object is arranged on the total reflection surface.

Provided is a system and method for active multispectral imaging having a transmitter that uses narrowband optical radiation to dynamically illuminate an object with modulated structured light in multiple spectral bands, and a receiver that includes an independent panchromatic imager. The transmitter and receiver can be operated in a bistatic decoupled configuration to enable passive multispectral synthesis, illumination-invariant sensing, optical communications, and the ability for the transmitter to emit a sequence of spectral bands in an order that is unknown to the receiver, and the receiver is able to passively decode the spectral identity from a band identifier embedded in the modulated structured light. The receiver passively decodes embedded high-bandwidth simplex communications while reconstructing calibrated multispectral images at video frame rates.

A concentration measurement device including at least one light source; a measurement cell for containing a fluid to be measured; a splitter for dividing light from the light source into incident light being incident into the measurement cell and non-incident light not being incident into the measurement cell; a transmitted-light detector for detecting transmitted light that is the incident light having passed through the measurement cell; a non-incident light detector for detecting the non-incident light; and an arithmetic part for correcting a detection signal of the transmitted-light detector using a detection signal of the non-incident light detector.

A spot shape detection apparatus for detecting the spot shape of a laser beam oscillated from a laser oscillator includes: a focusing leans for focusing the laser beam oscillated by the oscillator; a rotary body (mirror holder) in which a plurality of mirrors for reflecting the laser beam having passed through the focusing lens are disposed on concentric circles; a drive source (motor) for rotating the rotary body at a predetermined period; a beam splitter for branching return beams of the laser beam reflected by the plurality of mirrors of the rotary body; an imaging unit which is disposed in a direction in which the return beams are branched by the beam splitter and which images spot shapes of the return beams; and a display unit for displaying images obtained by imaging by the imaging unit, in relation with the plurality of mirrors.

In a gas detection device and a gas detection method of the present invention, detection target gas is detected on the basis of reflected light of detection light (sensing light) frequency-modulated with respect to a center frequency and a distance to an object that generates the reflected light is measured. In the gas detection, an output signal of a light reception unit for receiving the reflected light is subjected to phase-sensitive detection. A synchronous detection timing of this phase-sensitive detection is adjusted on the basis of the measured distance to the object.

Apparatus and methods for providing an improved Fabry-Perot interferometer (FPI)-based spectrometer are disclosed herein. The improved FPI-based spectrometer may comprise one or more of a variety of improvements to allow improved sensitivity while retaining high spectral resolution, to limit the susceptibility to stray light, and to limit the degradation in performance due to temporal instabilities in the light source.

Technologies are generally described for concurrent activation of multiple illumination sources to analyze a sample. A controller may be configured to activate the illumination sources substantially simultaneously, where a current or voltage of each activated illumination source is modulated at a different frequency by respective circuit drivers of the controller. Each activated illumination source may be configured to illuminate the sample with light at a different emission wavelength, and one or more detectors may be configured to detect a composite signal from the sample in response to the illumination. The composite signal may include multiple returned signals, where each returned signal corresponds to light emitted from one of the activated illumination sources at a respective emission wavelength. One or more filters, each associated with a respective modulation frequency of one activated illumination source, may be configured to extract each returned signal from the composite signal for analysis.

An electronic device includes one or more light sources for emitting light toward a body part of a user and one or more optical sensors for capturing light samples while each light source is turned on and for capturing dark samples while the light source(s) are turned off. A signal produced by the one or more optical sensors is filtered and demodulated produce multiple demodulated signals each associated with a light source. Each signal associated with the light source(s) is analyzed to estimate or determine a physiological parameter of the user.