Circuit, procedure, and algorithm to operate SiPMs in optimal conditions for fNIRS / DOT systems

The present invention relates to a system and method for brain tissue analysis comprising: at least one silicon photomultiplier (1) being configured to change from a rest state to an excited state when excited by light, the excited state corresponding to a linear state when the value of the excited state is comprised between a minimum linear value and a maximum linear value; at least one optical element (2) comprising at least two emitting sources, each emitting source being configured to emit light at a given mean wavelength with full width half maximum at least less than 50% of the mean when the optical element is supplied by an electrical power; a source of electric voltage (3) in signal communication with the silicon photomultiplier (1) and configured to supply a given electric voltage to the silicon photomultiplier (1); a digital control and data elaboration unit (4) in signal communication with the silicon photomultiplier (1) and with the optical element (2) and comprising a control unit configured to define an optical and electrical association between the optical element (2) and the silicon photomultiplier (1) and to define a value of electrical power to be supplied to the optical element (2), the digital control and data elaboration unit (4) being configured to supply the value of electrical power defined by the control unit to the optical element (2); a memory unit in signal communication with the digital control and data elaboration unit (4) and having stored the minimum linear value and the maximum linear value of the linear state of the silicon photomultiplier (1) and being configured to store values of electrical power; a measuring unit (5) in signal communication with the silicon photomultiplier (1) and with the control unit and configured to measure a value of the excited state of the silicon photomultiplier (1); in which the control unit is configured to verify if the value of the excited state is comprised between the minimum linear value and the maximum linear value, to change the value of electrical power to be supplied to the optical element (2) when the value of the excited state of the silicon photomultiplier (1) is lower than the minimum linear value or greater than the maximum linear value and to store in the memory unit the value of the electrical power to be supplied to the optical element (2) when the value of the excited state of the silicon photomultiplier (1) is comprised between the minimum linear value and the maximum linear value