A photoelectric sensor includes: a placement table configured to allow a workpiece to be placed thereon; a light projecting device including a light emitting element configured to emit light and a converging element configured to converge the light emitted from the light emitting element toward a detection area; and a light receiving device configured to receive the light passing through the detection area from the converging element at a position located on a same plane as the placement table in a direction along an optical axis of the light. The optical axis of the light projected from the light projecting device is set such that the light is incident in a direction perpendicular to an incident surface of the light receiving device and focused on the incident surface of the light receiving device.

A laser detection system comprises a sample chamber configured to receive and contain a volume of sample gas, one or more lasers within at least one laser housing, wherein each laser is configured to produce a respective laser beam for excitation of one or more different materials in the sample gas and the one or more lasers are outside the sample chamber, a detector apparatus for detecting light output from the sample chamber, a first optical interface to the sample chamber having at least one window that is at least partially transparent to the laser beams from the one or more lasers, wherein the at least one laser housing is positioned in a close-coupling arrangement relative to the at least one window of the first optical interface such that, in use, the laser beams are substantially unmodified by passage between the laser housing and the at least one window.

A system for non-invasively measuring an analyte in a vehicle driver and controlling a vehicle based on a measurement of the analyte. At least one solid-state light source is configured to emit different wavelengths of light. A sample device is configured to introduce the light emitted by the at least one solid-state light source into tissue of the vehicle driver. One or more optical detectors are configured to detect a portion of the light that is not absorbed by the tissue of the vehicle driver. A controller is configured to calculate a measurement of the analyte in the tissue of the vehicle driver based on the light detected by the one or more optical detectors, determine whether the measurement of the analyte in the tissue of the vehicle driver exceeds a pre-determined value, and provide a signal to a device configured to control the vehicle.

A light emitting apparatus has light emitting units. The light emitting units can be respectively provided with current densities, so that the light emitted by each of the light emitting unit has a light intensity, wherein the current densities are different from each other, or partial of the current densities are different from each other. A number of the light emitting units can be larger than or equal to four, all of the four lighting frequencies of the four light emitting units are different from each other, or partial of the four lighting frequencies of the four light emitting units are identical to each other, and the light emitting apparatus and the object under test rotate relative to each other. A light emitting method, a spectrum detection method and a lighting correction method are also illustrated for increasing SNR, correcting the light intensity or the spectrum signal.

This invention relates to a method of and system for facilitating detection of a particular predetermined gas in a scene under observation. The gas in the scene is typically associated with a gas leak in equipment. To this end, the system comprises an infrared camera arrangement; a strobing illuminator device having a strobing frequency matched to a frame rate of the camera; and a processing arrangement. The processing arrangement is configured to store a prior frame obtained via the infrared camera arrangement; and compare a current frame with the stored prior frame and generate an output signal in response to said comparison. The system also comprises a display device configured to display an output image based at least on the output signal generated by the processing arrangement so as to facilitate detection of the particular predetermined gas, in use.

In an embodiment an apparatus includes at least one optoelectronic laser configured to provide excitation radiation to a sample, the excitation radiation being generated by an electric current flowing through the at least one optoelectronic laser, a transistor configured to modulate the electric current flowing through the at least one optoelectronic laser in order to switch on and off generation of the excitation radiation and a spectrometer configured to analyze Raman light scattered from the sample in response to exposing the sample to the excitation radiation, wherein the Raman light includes one or more spectral components, wherein the spectrometer includes a diffraction element configured to split the Raman light into the spectral components, and wherein the diffraction element includes at least a photonic crystal or a plasmonic Fabry Perot filter.

The present invention relates to a normal incidence ellipsometer and a method for measuring the optical properties of a sample by using same. The purpose of the present invention is to provide: a normal incidence ellipsometer in which a wavelength-dependent compensator is replaced with a wavelength-independent linear polarizer such that equipment calibration procedures are simplified while a measurement wavelength range expansion can be easily implemented; and a method for measuring the optical properties of a sample by using same.

An optical sensing system includes at least one electro-optical sensor having an adjustable field of view and at least one reflective member including a diffuse reflector surface positioned within the field of view of the at least one electro-optical sensor. The system also includes at least one controller configured to generate calibration parameters for the at least one electro-optical sensor based on data for at least one exposure detected by the electro-optical sensor when the diffuse reflector surface is within the field of view of the at least one electro-optical sensor. Methods for calculating the calibration parameters and for directly measuring reflectivity of objects in a scene with at least one electro-optical sensor are also disclosed herein.

Building blocks are provided for on-chip chemical sensors and other highly-compact photonic integrated circuits combining interband or quantum cascade lasers and detectors with passive waveguides and other components integrated on a III-V or silicon. A MWIR or LWIR laser source is evanescently coupled into a passive extended or resonant-cavity waveguide that provides evanescent coupling to a sample gas (or liquid) for spectroscopic chemical sensing. In the case of an ICL, the uppermost layer of this passive waveguide has a relatively high index of refraction that enables it to form the core of the waveguide, while the ambient air, consisting of the sample gas, functions as the top cladding layer. A fraction of the propagating light beam is absorbed by the sample gas if it contains a chemical species having a fingerprint absorption feature within the spectral linewidth of the laser emission.

A beating spectroscopy device includes: first and second quantum cascade lasers; a quantum cascade detector; and a sample holder configured to hold a sample on an optical path between the second quantum cascade laser and the quantum cascade detector. Lights from the first and second quantum cascade lasers are detected by the quantum cascade detector while a wavelength of the light from the second quantum cascade laser is changed to scan a frequency of a beating signal having a frequency in accordance with a wavelength difference between the lights from the first and second quantum cascade lasers.