Optical analysis system and method
AssigneeKoninklijke Philips N.V.
InventorsAlphonsus Tarcisius Jozef Maria Schipper, Koen Geenen
Life of this patent
Estimating the term…
Abstract
An optical analysis system and method is provided in which a sample is analyzed using a light source. An optical sensor signal is processed using a first signal processing circuit and an electrical signal, which is representative of a drive signal applied to the light source, is processed using a second signal processing circuit. The sensor signal is further processed to improve the signal to noise ratio using the processed electrical signal as a reference.
Claims12
An optical analysis system, comprising:
- a light source for illuminating a sample to be analyzed;
- a driver for operating the light source;
- a photodetector for receiving light reflected by or transmitted through the sample to be analyzed and generating a sensor signal;
- a first signal processing circuit for processing the sensor signal and which comprises a transimpedance amplifier;
- a second signal processing circuit for processing an electrical signal provided by the driver which is representative of the drive signal applied to the light source;
- and
- a compensation circuit for further processing the sensor signal to improve the signal to noise ratio using the processed electrical signal, characterized in that the second signal processing circuit comprises a filter having a filter frequency characteristic which corresponds to the frequency transfer characteristic of the transimpedance amplifier.
A system as claimed in any preceding claim, wherein the compensation circuit comprises:
- a normalizing circuit for normalizing the processed electrical signal and providing a multiplier which is the reciprocal of the normalized processed electrical signal;
- and
- a scaling element which provides a scaling factor corresponding to the multiplier.
An optical analysis method, comprising:
- illuminating a sample to be analyzed using a light source;
- receiving light reflected by or transmitted through the sample to be analyzed and generating a sensor signal in response thereto;
- processing the sensor signal using a first signal processing circuit which comprises a transimpedance amplifier;
- processing an electrical signal which is representative of a drive signal applied to the light source using a second signal processing circuit wherein the second signal processing circuit comprises a filter having a filter frequency characteristic which corresponds to the frequency transfer characteristic of the transimpedance amplifier;
- and
- further processing the sensor signal to improve the signal to noise ratio using the processed electrical signal.
Dependencies are inferred from the claim text.