Patent ID: 8766189

Claim:
An optical system for detecting a presence of a living biological element, comprised of at least one pair of light sources ( 1 ; 2 ; 3 ) that emit pulsed electromagnetic radiation with an emission band located in a near-infrared zone of the electromagnetic spectrum; at least one pair of light sources ( 1 ; 2 ; 3 ) that emit pulsed electromagnetic radiation with an emission band located in a near-ultraviolet zone of the electromagnetic spectrum; at least one photodetector ( 4 ) with an absorption band located in the near-infrared zone of the electromagnetic spectrum, for detecting the pulsed radiation transmitted and reflected on the biological element, on a basis of the pulsed radiation emitted by the pair of light sources that emit the radiation with the emission band located in the near-infrared zone; at least one photodetector ( 5 ) with an absorption band located in the near-ultraviolet zone of the electromagnetic spectrum, for detecting the pulsed radiation reflected on the biological element, on a basis of the pulsed radiation emitted by the pair of light sources ( 1 ; 2 ; 3 ) that emit the radiation with the emission band located in the near-ultraviolet zone; a control unit ( 8 ( c )), connected to the pairs of light sources and to the photodetectors, which interprets the pulsed radiation transmitted and reflected on the biological element and detected by the photodetectors; and a processing unit ( 8 ( d )), connected to the control unit, which determines if the biological element is a living biological element, on a basis of the radiation interpreted by the control unit, and by an emission of a periodic signal obtained by the pulsed radiation emission of the pairs of light sources on an alternate basis, due to a sinusoidal electrical signal configured for the emission of the pairs of light sources.