Mindray PM-9000, Operation Manual

Page: 188 / 378

SpO
2
Monitoring
12-4
12.2 Mindray SpO
2
Module
NOTE
z
This section is only applicable to the monitor equipped with a Mindray
SpO
2
module.
12.2.1 Principles of Operation
SpO
2
monitoring is a non-invasive technique used to measure the amount of
oxygenated haemoglobin and pulse rate by measuring the absorption of selected
wavelengths of light. The light generated in the probe passes through the tissue and
is converted into electrical signals by the photodetector in the probe. The SpO
2
module processes the electrical signal and displays on the screen a waveform and
digital values for SpO
2
and pulse rate.
The sensor measurement wavelengths are nominally 660nm for the red LED and
940nm for infrared LED. The maximum optical power output for LED is 4mW.