Patent ID: 9480407
Filing Date: 2016-11-01
CPC Classification: A61B,F04C,G01N

Claim Text:
1. A method for removal of ambient noise signal from an optical measurement, the method comprising: obtaining a first signal waveform based on detecting light based on a first light illumination; obtaining a second signal waveform based on detecting light based on a second light illumination; tuning the first light and second light illumination such that the maximum amplitudes of the first and second signal waveforms are maximised and within a predetermined saturation range, such that ambient light interference for the first and second signal waveforms is reduced; obtaining a third signal waveform based on detecting ambient light; obtaining respective maximum and minimum values of the first and the second signal waveforms, said obtaining respective maximum and minimum values being performed at a plurality of identified sample points; and deriving signal values of the first and second signal waveforms with the removal of ambient noise using the third signal waveform and by using the maximum and minimum values of the first and the second signal waveforms.