Table 1.

Wearable fiber optic technology applications in healthcare monitoring.

Reference	Working Mechanism	Application	Integration Method	Location on Body	Characteristics
Koyama et al. (2018) [22]	Intensity modulated	Heartbeat and respiration monitoring	Woven with wool fabric into garment	Chest surface	Comfort; real-time function; high accuracy; ability to sense minute-load changes
Li et al. (2018) [16]	Wavelength modulated	Wrist pulse, respiration, and finger pulse monitoring	Embedded in PDMS	Wrist, chest, and finger	High sensitivity of 0.83 kPa−1; real-time function; flexibility; wearability; cost-effectiveness
Arnaldo et al. (2018) [36]	Intensity modulated	Gait monitoring	Attached to insole, orthotic device, and modular exoskeleton	Foot	Flexibility; high repeatability; low cost; simple signal processing; measurement of joint angles and detection of gait events for gait assistance and rehabilitation
Lo Presti et al. (2017) [34]	Wavelength modulated	Respiratory monitoring	Glued by polymeric glue	Chest wall	Monitoring in harsh environments; ability to measure in different positions of the human body
Najafi et al. (2017) [35]	Wavelength modulated	Plantar pressure and temperature monitoring	Embedded into socks	Foot	Quick feedback; real-time function; convenience
Fajkus et al. (2017) [17]	Wavelength modulated	Body temperature, respiration, and heart rate monitoring	Encapsulated inside PDMS	Chest surface	Non-invasiveness; high accuracy; multichannel hybrid fiber optic sensor system
Hu et al. (2016) [18]	Wavelength modulated	Respiratory monitoring	Attached to seat-back	Back	Real-time function; high accuracy; low cost; convenient operation
Ciocchetti et al. (2015) [20]	Wavelength modulated	Respiratory monitoring	Glued by adhesive silicon rubber	Chest surface	Non-invasiveness; good linear response to strain; chemical inertness; small size; flexibility; MR compatibility; high accuracy in the estimation of TR, TI, and TE phases and UT volumes.
Yang et al. (2015) [19]	Intensity modulated	Heartbeat respiration monitoring	Integrated onto an elastic substrate	Back or chest	Simultaneous measurement in daily activities; comfort; cost-effectiveness; high sensitivity; non-invasiveness; simple fabrication
Zheng et al. (2014) [15]	Intensity modulated	Respiration monitoring	Embedded into belt fabric	Chest or abdomen	High strain sensitivity; low hysteresis and repeatability; immunity to electromagnetic interference
Witt et al. (2012) [21]	Wavelength modulated	Respiration monitoring	Integrated into textile-based sensing harness	Abdominal and thoracic areas	Comfort; continuous measurement; testing in MR environment

FBG: fiber Bragg grating; MR: magnetic resonance; T_R: respiratory period; T_I: duration of inspiratory; T_E: expiratory; UT: upper thorax; PDMS: polydimethylsiloxane polymer