METER AND METHOD OF MEASURING REDUCED LUMINESCENCE BRIGHTNESS OF PAPER Russian patent published in 2025 - IPC G01N21/63 

FIELD: measuring.

SUBSTANCE: invention relates to analytical instrument-making, specifically to devices for analysing optical characteristics of luminescence of materials arising under the action of exciting UV radiation with two wavelengths of maximum radiation – 265 and 370 nm. Meter of the reduced luminescence brightness of the paper contains a measuring probe connected by a cable to the analysis unit, and a control measure of the reduced luminescence brightness. Measuring probe comprises a first housing, on one of its surfaces there is an optically transparent section, inside the housing there is a LED module facing the optically transparent section of the first housing, comprising at least LEDs with wavelengths of 265 and 370 nm with a conical mirror, the wide base facing the LEDs, and the narrow one – to the optically transparent section, and a receiving optical unit located opposite the optically transparent section, which includes a series-installed condenser, a correcting light filter, a collective and a photodetector module, having its own microcontroller and ADC, connected in such a way that the signal from the photodetector arrives to the ADC, and from the output of the ADC – to the microcontroller. Analysis unit comprises installed in the second housing a control module and a processing module, wherein the processing module comprises a microcontroller configured to receive and process a signal coming from the measuring probe, and transmitting the processed signal value to the control module, which includes a display for displaying data and a film keyboard for controlling the meter, and the reference measure of the reduced luminescence brightness is a housing with a cone-shaped recess in the end part for mounting a measuring probe, at the bottom of the recess there is a luminophore sample with known characteristics of the reduced luminescence brightness.

EFFECT: providing the possibility of measuring the reduced luminescence brightness of various types of paper (writing, printing, et cetera), images applied on paper, and other image carriers with a flat surface.

4 cl