A measurement apparatus for measuring a coating amount of a slurry according to the present disclosure includes a light emitter configured to irradiate terahertz wave onto a release paper coated with the slurry, a light receiver configured to receive the terahertz wave, which is irradiated from the light emitter and passes through the release paper coated with the slurry, to obtain a power of the terahertz wave, and a calculating part configured to calculate a thickness of an electrode, formed from the slurry applied to the release paper, based on the power of the terahertz wave received by the light receiver.

An aim is to reduce the size of an optical sensor which detects radiated light such as phosphorescence radiated from a detection target excited by exciting light, and to increase a radiated light receiving surface of the optical sensor. An optical sensor is configured to be provided with: a light source which irradiates excitation light; a light detector which detects radiation light emitted from a detection target excited by the excitation light; and a single light guide unit which guides the excitation light to the detection target and guides the radiation light to the light detector.

A measurement apparatus for measuring a coating amount of a slurry according to the present disclosure includes a light emitter configured to irradiate terahertz wave onto a release paper coated with the slurry, a light receiver configured to receive the terahertz wave, which is irradiated from the light emitter and passes through the release paper coated with the slurry, to obtain a power of the terahertz wave, and a calculating part configured to calculate a thickness of an electrode, formed from the slurry applied to the release paper, based on the power of the terahertz wave received by the light receiver.

The invention relates to a method, comprising illuminating an area of a wood fibre web by directing ultraviolet light to an area of the web by an ultraviolet light source, capturing an image of at least part of the illuminated area by an imaging device comprising a colour filter, transmitting image data of the captured image to an image data processing device, and analysing if the captured image comprises a fluorescent liquid stain emitting fluorescent light passed through the colour filter. The invention further relates to a machine vision system and a computer program product for detecting fluorescent liquid stains from a wood fibre web.

A measurement apparatus of a moving paper web, includes an optical radiation source that outputs optical radiation toward a scattering element of the measurement apparatus. The scattering element scatters the optical radiation, and a transmitting surface of the scattering element directs the optical radiation in a scattered manner toward the moving paper web. A distance between said transmitting surface of the scattering element and a surface of the paper web is known, and the transmitting surface and a detector of the apparatus are on opposite sides of the paper web. The detector receives at least a part of the optical radiation, which is side-scattered from the moving paper web. The detector determines a moisture value and a dry weight of the paper web on the basis of spectral information on the received optical radiation and the known distance.

Provided is a discriminating device including a light-receiving unit receiving light beam from a detected surface (DS) and an optical unit (OU) guiding light beam from DS to light-receiving unit, and satisfying following conditional expressions:
0.01|m1/m01|, and
1<|m1/m01|/|s1/s01|,
where m0 represents a magnification of OU with respect to a first direction in a first cross section parallel to DS when DS is at a first position, m1 represents a magnification of OU with respect to first direction in first cross section when DS is at a second position shifted from first position by +0.2 mm in a direction perpendicular to DS, s0 represents a magnification of OU with respect to a second direction perpendicular to first direction in first cross section when DS is at first position, and s1 represents a magnification of OU with respect to second direction in first cross section when DS is at second position.

A light detection sensor includes a light source that irradiates a detection target with light, a rod lens that collects emitted light from the detection target, a first light receiving element that detects the emitted light that has passed through the rod lens, and a second light receiving element that detects the emitted light that has passed through the rod lens, at a position different from a position at which the first light receiving element detects the light.

The present disclosure includes systems and methods for calibration of an optical sensor package, including setting an initial detection threshold of a detector, gradually increasing a power level of a signal generator that is in communication with a detector to cause a detected power at the detector to exceed the initial detection threshold, storing in a memory a first power level of the signal generator at which the detected power at the detector exceeds the initial detection threshold, and adjusting the initial detection threshold of the detector to an adjusted detection threshold to include a detection buffer amount within the adjusted detection threshold.

A method of measuring the thickness of long sheet material wound on to a reel spool while being pressed by a reel drum, includes: measuring the increase in the roll diameter of the wound roll formed from the long sheet material in a non-contact manner; measuring the number of rotations of the reel spool; and determining the thickness of the long sheet material by calculation using the measured increase in the roll diameter and the number of rotations.

According to an embodiment, a paper sheet processing device includes a fluorescence reference member, a light source, and a sensor. The fluorescence reference member is configured to demonstrate fluorescence in accordance with an intensity of excitation light applied. The light source configured to apply the excitation light to the fluorescence reference member and a paper sheet. The sensor configured to take, at a plurality of sensitivity wavelengths, images of irradiation surfaces of the fluorescence reference member and the paper sheet being irradiated with the excitation light. The fluorescence reference member includes a transmittance control element for the excitation light.