Dual coupler device, spectrometer including the dual coupler device, and non-invasive biometric sensor including the spectrometer

A spectrometer comprising:

• a first coupler layer configured to receive light of a first polarization component among incident light;
• a second coupler layer configured to receive light of a second polarization component among the incident light;
• and
• a photodetector configured to detect the light received by each of the first coupler layer and the second coupler layer, and
• wherein the first coupler layer comprises:
• a first waveguide along which the light of the first polarization component propagates;
• a first resonator disposed in the first waveguide, the first resonator being configured to resonate light of a first wavelength band among the light of the first polarization component;
• a second waveguide along which the light of the first polarization component propagates;
• and
• a second resonator disposed in the second waveguide, the second resonator being configured to resonate light of a second wavelength band different from the first wavelength band among the light of the first polarization component, and
• wherein the second coupler layer comprises;
• a third waveguide along which the light of the second polarization component propagates;
• a third resonator disposed in the third waveguide, the third resonator being configured to resonate light of the first wavelength band among the light of the second polarization component;
• a fourth waveguide along which the light of the second polarization component propagates;
• and
• a fourth resonator disposed in the fourth waveguide, the fourth resonator being configured to resonate light of the second wavelength band among the light of the second polarization component.