A magnetometer includes: a substrate; a diamond layer on the substrate, in which the diamond layer includes a defect sub-layer including multiple lattice point defects; a microwave field transmitter; an optical source configured to emit light including a first wavelength that excites the multiple lattice point defects from a ground state to an excited state; a photodetector arranged to detect photoluminescence including a second wavelength emitted from the defect sub-layer, in which the first wavelength is different from the second wavelength; and a magnet arranged adjacent to the defect sub-layer.

A system for the automatic grading of a cut/polished gemstone (SUT) includes an enclosure with a stage for mounting the cut/polished SUT. The enclosure further includes one or more sources of broadband visible (BBV) light, the sources of BBV light being controllable by a programmable controller; an image sensor for capturing a plurality of images of a mounted SUT, and one or more sources of UV light mounted within the enclosure. The controller captures images of the mounted SUT from one or more selected angles relative to the sensor elevation axis and relative to the position of the SUT on the stage rotation axis; an image capturing module is configured for processing the one or more images; and, a light grade calculation module is configured for grading the cut/polished SUT using light indicative parameters from at least a part of the one or more images captured.

Compositions, articles, systems, and methods for sensing and/or authentication using luminescence imaging are generally provided. In some embodiments, an article (or packaging material of an article) is associated with an emissive material comprising an emissive species (e.g., a luminescent species). In some cases, the emissive species has an emission lifetime of at least 10 nanoseconds (ns). In some cases, a characteristic of an article (e.g., identity, authenticity, age, quality, purity) may be determined by obtaining an image (or series of images) comprising time-dependent information related to an emissive species. In certain instances, for example, the emission lifetime of an emissive species may be determined from an image (or series of images). Since the emission lifetime of an emissive species may be modified by a number of factors, including but not limited to binding or proximity to other molecules (e.g., water, oxygen, carbon monoxide), temperature, pH, and radiation exposure, the measured length of the emission lifetime (e.g., the observed emission lifetime, the emission time period) may provide information regarding a characteristic of an associated article. In some instances, an emissive material comprising one or more emissive species may be used to identify and/or authenticate an associated article.

The disclosure provides methods for the measurement of ground water characteristics. The carbon dot tracer is injected in an injection bore well. Carbon dot tracer and ground water are thoroughly mixed in the injection bore well. The ground water mixed with carbon dot tracer is pumped from the injection bore well to an acquiring bore well connected with injection bore well with micro and major fracture; the water samples mixed with carbon dot tracer were collected at the acquiring bore well. The characteristics of the ground water were measured by measuring fluorescence. The disclosure further relates to a method for depicting the solute transportation in the soil.

A detecting apparatus for use in specifying regions having different impurity concentrations in an ingot includes an ingot holding unit having a holding surface for holding the ingot thereon, an excitation light source for applying excitation light having a predetermined wavelength to a face side of the ingot held on the holding surface, and a photodetector for detecting fluorescence emitted from the ingot upon exposure to the excitation light and generating an electric signal representing a number of photons of only light whose wavelength is in an infrared radiation range, of the detected fluorescence.

There is provided is sliding body surface evaluation method and apparatus configured so that a temporal change in a transformed portion at a sliding portion of a sliding body can be observed. The method includes a first step of irradiating, with an electromagnetic wave, a sliding portion of a sliding body sliding on a sliding target body, a second step of detecting light emitted from the sliding portion irradiated with the electromagnetic wave, and a third step of deriving a change in a light emission state of the sliding portion.

Two or more upconverting particles are attached to each unit of one or more units of a chemical component in a sample, to form, for each unit of the chemical component, a multi-particle complex including the unit of the chemical component and two or more corresponding upconverting particles. The sample is illuminated by input light having a first wavelength. Light is received at an imaging sensor, the received light including output light generated by at least a portion of the upconverting particles attached to the units of the chemical component, the output light having a second wavelength that is shorter than the first wavelength. One or more images of the sample are captured from the received light. Based on the captured one or more images, a presence or a level of the chemical component in the sample is determined.

An evaluation method of a SiC epitaxial wafer includes: a first observation step of preparing a SiC epitaxial wafer having a high-concentration epitaxial layer having an impurity concentration of 1×10.sup.18 cm.sup.−3 or more, irradiating a surface of the high-concentration epitaxial layer having an impurity concentration of 1×10.sup.18 cm.sup.−3 or more with excitation light, and observing a surface irradiated with the excitation light via a band-pass filter having a wavelength band of 430 nm or less.

A multi-functional precious stone testing apparatus includes a portable housing and a testing unit. The portable housing includes a portable housing having a hand-held casing and a probe casing extended from a front end of the hand-held casing. The testing unit housed in the hand-held casing includes a UV light emission unit, a UV light reflecting and guiding unit, and a UV light receiving unit. The UV light emission unit produces and emits both a long-wave UV light and a short-wave light, so as to allow the UV receiving unit to sense the UV lights reflected and refracted by a testing object for determining various qualities and distinguishing types of diamond of the testing object.

A liquid measuring system (LMS) comprising: a light source; a multi-region optical filter (MROF); a sample cell configured to contain a liquid sample; an optical detection subsystem (ODS) having an optical detector for measuring optical properties of light emanating from the liquid sample. The MROF may include a spectral filter region such as a bandpass or a long-pass filter type region, and natural density (ND) type filter region, for enabling simultaneous optical measuring at least of turbidity level and algae concentration in a water sample contained by the sample cell, by having light passed through the water sample and the MROF before reaching the optical detector of the ODS. Embodiments of the MROFs may be also used, for example for selective spectral attenuation of light illuminating the liquid sample to achieve reduction in distortions due to stray light.