Acta Mechanica Slovaca 2026, 30(1):58-63 | DOI: 10.21496/ams.2026.013

Metrological Comparison of Ocular Tonometers for Optometric Use

Stela Levická1, *, Dominik Pražák2, Václav Sedlák2, Eliška Najmanová1, František Pluháček1
1 Department of Optics, Faculty of Science, Palacký University, 17. listopadu 12, 771 46 Olomouc, Czech Republic
2 Unit of Primary Metrology of Pressure, Vacuum and Low Mass Flow, Czech Metrology Institute, Okružní 31, 638 00 Brno, Czech Republic

This paper presents an international metrological comparison of non-contact tonometers used for measuring intraocular pressure (IOP), a critical parameter in glaucoma diagnosis. Since non-contact tonometry is affected by biological variability and lacks direct linkage to SI units, reliable calibration standards are essential. A newly developed universal model eye, independent of specific manufacturers and traceable to SI units, served as the primary metrological standard. The comparison involved tonometers tested at institution in the Czech Republic and Slovakia according to the ISO 8612:2009 standard under controlled laboratory conditions. Accuracy, repeatability, and deviations from reference values were evaluated. Results demonstrated stable performance with minimal deviations across the measured pressure range. The study confirms the suitability of the developed model eye as a universal calibration standard and highlights the importance of international comparisons for enhancing the reliability and standardization of IOP measurements in clinical practice.

Keywords: Intraocular pressure, Metrological comparison, Metrological traceability, Ocular tonometers

Received: February 15, 2026; Revised: March 11, 2026; Accepted: March 18, 2026; Published: April 1, 2026  Show citation

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Levická, S., Pražák, D., Sedlák, V., Najmanová, E., & Pluháček, F. (2026). Metrological Comparison of Ocular Tonometers for Optometric Use. Acta Mechanica Slovaca, 30(1), 58-63. doi: 10.21496/ams.2026.013
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