Testing device for applanation tonometer
laser interferometric force sensor
traceability to national standards by calibrating the force sensor with a 5g standard weight
test specimen is calibrated on the statically mounted force sensor
graphic display of the entire tonometer characteristic curve possible
certificates of the Physikalisch-Technische Bundesanstalt and the Landesamt für Mess- und Eichwesen Thüringen (State Office for Metrology and Verification Thuringia)
The interference-optical test device for applanation tonometers consists of an automated laser-optical test apparatus with USB interface and evaluation software for PC/laptop. Due to the variable design, the test device is suitable for different types of applanation tonometers. The applanation force set on the tonometer to be tested is automatically detected in the entire range of mobility of the tonometer. By detecting the mobility limits of the tonometer, the complete force characteristic curve over the mobility range can be displayed graphically in addition to the applanation force value to be determined in the center of the mobility range according to the test specification.
The sensor used is an interference-optical force sensor with a resolution of 0.01 mN and a measuring range of 100 mN. To determine the measured value, the tonometer is moved against the force sensor using an electromechanical drive unit. The measured force progression is used internally to control the movement sequence
itself and for detecting the limits of mobility. The measured tonometer force value in the center of the range of motion is compared with the permissible
The measured tonometer force value in the center of the mobility range is compared with the permissible tolerance specifications and displayed in green (within the tolerance range) or red (outside the tolerance range). The duration of a complete series of measurements with printout
of the calibration certificate is less than 5 minutes due to the automated test sequence.
The possibility of calibrating the interference-optical force sensor with a standard weight ensures traceability to national standards.