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  3. Volume 86, no.4, 2025
  4. METHOD FOR MONITORING THE FILL LEVEL OF AN INHALER RESERVOIR

METHOD FOR MONITORING THE FILL LEVEL OF AN INHALER RESERVOIR

ISTCMTM.
2025;
Volume 86(4), Number 4
: 45-51
https://doi.org/10.23939/istcmtm2025.04.
Authors:
  1. Myroslav Tykhan
  2. Oleksiy Didkovskyi
1
Lviv Polytechnic National University
2
Lviv Polytechnic National University

This paper proposes an optical method for monitoring the fill level of an inhaler reservoir, based on the phenomenon of total internal reflection within a light guide. A detector design has been developed that enables the detection of the presence of working fluid (glycerine, propylene glycol, or their mixture) in various orientations of the inhaler. A theoretical analysis of the operational boundary conditions has been conducted, including calculations of light losses in the light guide depending on its material and surrounding medium. Additionally, a method for determining the critically low level of working fluid in the inhaler reservoir has been developed. The functionality of the proposed method has been experimentally validated. This approach can be applied in biomedical devices to enhance the safety and comfort of inhalation therapy.

Inhaler
liquid fill monitoring
optical sensor
light guide
liquid detector
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