Robust, Speckle-Tolerant Handheld Non-Contact Vital Sign Monitor With Photonics IC

To aid Combat MedicÆs triage of injured Warfighters, the non-contact Vital Signs Monitor (ncLVSM) is a chest-mount device that autonomously retrieves select vital signs of the Warfighter while the medic tends the injuries. The vital signs to be monitored include the heart rate (HR), respiration rate (HR), arterial waveform (AWF), and the AWF-derived systolic pressure (SBP) and diastolic pressure (DBP), while the core body temperature (Tc) derives from serial measurements of HR via the ECTemp algorithm. In Phase I, we iteratively investigated various component technologies and arrived at the design of the ncLVSM that supports small form factor similar to that of smartphones, thanks to the GovernmentÆs invaluable guidance in adopting photonic integrated circuit (PIC) in the ncLVSM while eliminating the conventional free space optics. We further designed, modeled, and validated in silico a novel laser beam projector using PIC-integrated cascaded Mach-Zehnder Interferometers (MZIs) that involves no moving parts. Combined with plastic-lens based laser projection and collection modules, the resultant ncLVSM design supports light-weight, robust operations in the harsh battlefield environment. With the designed-in human pose estimation, the ncLVSM is capable of automatically locating the injured Warfighter, pinpoint his/her pose and pulse points, and retrieve raw waveforms using laser following a preset guidelines, resulting in the retrieval and display of vital signs after signal conditioning, processing, and analysis. In Phase II, component technologies are to be validated experimentally, leading to the final prototype build which will be used to collect vital signs in human subject studies after appropriate IRB approval.