Optical sensing module

An optical sensing module suitable for wearable devices, the optical sensing module comprising:

• a silicon or silicon nitride transmitter photonic integrated circuit (PIC), the transmitter PIC comprising:
• a plurality of lasers, each laser of the plurality of lasers providing a laser output at a wavelength that is different from the wavelength of the laser outputs of the other lasers within the plurality of lasers;
• an optical manipulation region, the optical manipulation region comprising one or more of:
• an optical modulator, optical multiplexer (MUX);
• and additional optical manipulation elements;
• and
• one or more optical sensor module outputs for light originating from the plurality of lasers to exit the optical sensing module;
• wherein:
• the plurality of lasers comprises one or more hybrid DBR lasers, each hybrid DBR laser having a III-V RSOA gain chip or coupon that is hybrid integrated to the PIC such that an optical mode in the III-V RSOA gain chip or coupon is edge-coupled to one or more waveguides of the PIC;
• and
• wherein each of the lasers of the plurality of lasers is switchable, to switch between an on configuration and an off configuration.