Abstract: A method for measuring a physiological signal is provided. The method is applicable to optical physiological measurement with at least two types of light sources. The method includes a processing for adjusting amplitudes of signals of the at least two types of light sources to a predetermined ratio by adjusting intensities of the light sources, so as to increase a signal dynamic range as well as a signal-to-noise ratio.

Abstract: A blood parameter measuring device and a method for measuring a blood parameter are provided. The blood parameter measuring device includes an emitted source, a receiver module, and an actuator. The emitted source is disposed at a side of a tissue to be analyzed and provides at least two different wavelengths of radiation. The receiver module is disposed at another side of the tissue to be analyzed to receive the attenuated radiation produced by the emitted source. The actuator is connected to at least one of the emitted source and the receiver module. The actuator generates a driving force to make the emitted source and the receiver module contacts the tissue to be analyzed, thereby imposing a normal stress on a surface of the tissue to be analyzed to change a wave path between the emitted source and the receiver module.