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 moisture detecting apparatus includes: a light emitting unit including a first light source configured to emit light having a first wavelength as a peak wavelength, and a second light source configured to emit light having a second wavelength as a peak wavelength; a detecting unit configured to detect a first detection value indicating an extent to which the light emitted from the first light source is transmitted through a recording material, and a second detection value indicating an extent to which the light emitted by the second light source is transmitted through the recording material, based on a light receiving result of a light receiving unit; and a determination unit configured to determine a value related to a moisture content of the recording material based on the first detection value and the second detection value.

An apparatus includes a chassis configured to move back and forth along multiple rails. The apparatus also includes electrical contacts configured to form electrical connections to the rails. The apparatus further includes a power converter/conditioner configured to receive power from the rails via the electrical contacts and to convert the power into a different form and/or condition the power. In addition, the apparatus includes one or more sensors configured to measure at least one characteristic of a material, where the one or more sensors are configured to operate using the power from the power converter/conditioner. The electrical contacts could touch the rails and receive the power directly from the rails. The electrical contacts could also touch rail contacts and receive the power indirectly from the rails via the rail contacts.

Embodiments of the invention relate to the automatic measuring of such qualities of a printed sheet as reflectance excluding specular reflectance, reflectance including specular reflectance, e.g. gloss, transmittance, half-tone coverage, and the like.

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.

An optical scanning device includes a reflected-light passing unit having a passing region through which a portion of reflected light that is the scanning light reflected by the medium passes. An outer peripheral contour line of the passing region includes a contour curve configured with a set of points where coordinates in a direction orthogonal to a scanning direction are uniquely determined for the coordinates in the scanning direction. The contour curve renders a curve protruded toward the passing region. When a region in contact with the contour curve in the passing region is divided into a plurality of quadrilateral minute regions having equivalent areas and extending from the contour curve to a predetermined coordinate position in the scanning direction and are continuously arranged in the orthogonal direction, widths of the minute regions in the scanning direction are different for each location in the orthogonal direction.

The invention relates to a method and arrangement for detecting free fiber ends in a paper surface. The method comprises illuminating a target sample (6) surface, which comprises free fiber ends, from at least two directions one at the time, with at least one light source (1). Original reflectance images are obtained for the target sample (6) surface with an imaging device (4), and a surface normal is estimated for each image pixel of the original reflectance image. Thus it is possible to reconstruct a reconstructed reflectance image from the estimated surface normals, and to compare the reconstructed reflectance image and the corresponding original reflectance image and to construct a difference image, where the differences represent shadow objects of the free fiber ends in a paper surface.

A method of measuring properties of a moving cellulose, paper or board sheet. A first parameter of a first resonance caused by the moving sheet in a frequency range 1 GHz to 25 GHz of electromagnetic radiation is measured. A second parameter of an electromagnetic signal transmitted between at least a pair of transceiver parts of a transceiver sensor located on opposite sides of the moving sheet through the moving sheet is measured in a frequency range 25 GHz to 1000 GHz. A minimum difference between the frequency ranges related to the first parameter and the second parameter being at least 5 GHz. Both the dry stuff content and the weight of water per unit of area are determined on the basis of the first parameter, the second parameter and available information related to a distance travelled by the electromagnetic signal.

The quality measurement method for a long sheet material W includes measuring cellulose fibers, % moisture, and % ash of the paper web W by using area cameras 1102 to 1106 having an infrared light receiving element and a light source 1100 having an infrared light emitting LED element. Performance check for the infrared cameras 1102 to 1106 over the entire width and correction of measured values are performed by using consistency between measured values for the same point in an overlap area measured by adjacent cameras and reference samples 1107 at the off-sheet positions provided at both sides.

An optical media sensor includes a guide wall, a light emitter, a light receiver and a blower. The guide wall has an opening. The light emitter emits light to a medium sheet through the opening. The light receiver detects an amount of light travelling from the medium sheet. The blower generates a wind pressure that presses the medium sheet against the guide wall when detecting the amount of light.