A system employing projected light upon objects or surfaces to determine a safe light wave length range of light to be emitted for treatment of the object or surface is provided. Light emitters are employed for projecting light waves upon the surfaces along with light reception components which are employed to receive reflected light wave ranges from such emitted light. Thereafter, a safe light wave range can be employed to treat or affect the object or surface.

This disclosure relates to a method for measuring an electric field in the near-field region of an optically excited sample. The method includes optically exciting at least part of the sample. This step includes directing excitation light onto an interface between the sample and a medium. The excitation light is incident onto the interface under an angle of incidence such that total internal reflection of the excitation light occurs at the interface. The method further includes measuring the electric field using a terahertz near-field probe, wherein the terahertz near-field probe is positioned on one side of the interface and the excitation light approaches the interface on another side of the interface. This disclosure further relates to a system and computer program for measuring an electric field in the near-field region of an optically excited sample.

A device may include a sensor window. The sensor window may include a substrate. The sensor window may include a set of layers disposed onto the substrate. The set of layers may include a first subset of layers of a first refractive index and a second set of layers of a second refractive index different from the first refractive index. The set of layers may be associated with a threshold transmissivity in a sensing spectral range, and may be configured to a particular color in a visible spectral range and associated with a threshold opacity in the visible spectral range. The device may include a spectral sensor device aligned to the sensor window and including at least one sensor element to receive light in the sensing spectral range and provide a plurality of sensing functionalities based on at least one measurement of the light in the sensing spectral range.

Provided is an identification method of plastic microparticles, including: performing an infrared analysis on plastic microparticles to identify whether the plastic microparticles include polyethylene terephthalate, polyethylene, polypropylene, or nylon 66, wherein the identification is to determine whether the plastic microparticles have a characteristic peak of each plastic, and the characteristic peak is selected from signals that do not overlap and interfere with each other in the infrared spectrum signals of each plastic.

Provided is an identification method of plastic microparticles, including: performing an infrared analysis on plastic microparticles to identify whether the plastic microparticles include polyethylene terephthalate, polyethylene, polypropylene, or nylon 66, wherein the identification is to determine whether the plastic microparticles have a characteristic peak of each plastic, and the characteristic peak is selected from signals that do not overlap and interfere with each other in the infrared spectrum signals of each plastic.

A method of optical analysis comprises receiving light at an optical spectrometer module from a light source, distributing the received light into two or more light beams with a light distribution component of the optical spectrometer module, concurrently exposing each of a reference and one or more test samples to one of the two or more light beams, and concurrently measuring a property of the light associated with each of the reference sample and one or more test samples with a corresponding detector.

A method of optical analysis comprises receiving light at an optical spectrometer module from a light source, distributing the received light into two or more light beams with a light distribution component of the optical spectrometer module, concurrently exposing each of a reference and one or more test samples to one of the two or more light beams, and concurrently measuring a property of the light associated with each of the reference sample and one or more test samples with a corresponding detector.

A terahertz scanner for detecting irregularities, such as chemical or structural variations, in a sample and methods of use thereof are described. The described terahertz scanner and algorithms allow for direct, high-sensitivity, high-throughput, and non-invasive detection of irregularities that range from chemical contaminant to material defects in a variety of substrates and settings.

A terahertz scanner for detecting irregularities, such as chemical or structural variations, in a sample and methods of use thereof are described. The described terahertz scanner and algorithms allow for direct, high-sensitivity, high-throughput, and non-invasive detection of irregularities that range from chemical contaminant to material defects in a variety of substrates and settings.

A quantum absorption spectroscopy system (100) includes a laser light source (1), a quantum optical system (201), a photodetector (31), and a controller (4). The laser light source (1) emits pump light. The quantum optical system (201) includes a nonlinear optical crystal (23) that generates a quantum entangled photon pair of a signal photon and an idler photon by irradiation with pump light, and a moving mirror (25) that changes a phase of the idler photon, and causes quantum interference between a plurality of physical processes in which the quantum entangled photon pair is generated. The photodetector (31) detects the signal photon when the phase of the idler photon is changed by the nonlinear optical crystal (23) in a state where a sample is disposed on an optical path of the idler photon, and outputs a quantum interference signal corresponding to the detected number of photons. The controller (4) calculates an absorption spectroscopy characteristic of the sample by performing Fourier transform on the quantum interference signal.