Table 1.

Description of Non-contact technologies.

Technology	Vital signs	Description	Scenarios	Pros	Cons
Image-based Visible light	HR, HRV, RR, SpO2	Uses visible light to detect subtle changes in skin color or motion	Pilot studies included all patient positions in isolettes and open cribs, most have infants in supine position ± wrap/clothes, stable patients, very few with resp support, most have ROIs manually selected	High spatial resolution	Affected by ambient light, limited performance in low light
Image-based infrared	RR, Temperature, SpO2	Detects infrared emission/absorption of the body to monitor blood flow, temperature, and RR	Supine and prone in isolettes and open cribs ± wrap/clothes, ROI selected	Works in low light, measures temperature distribution	Lower spatial resolution compared to visible light, prone to drift
Radar-based	HR, HRV, RR	Uses radar waves to detect minute movements caused by cardiac and respiratory activities	Supine, prone, and side-lying, some co-bedded with twin, isolettes and open cribs ± wrap/clothing, acute patients, respiratory support	Not affected by lighting conditions, can work through clothing	Requires precise calibration and more complex algorithms

HR, heart rate; HRV, heart rate variability; RR, respiratory rate; ROI, region of interest.