Fully Photonic Integrated Wearable Optical Interrogator

Abstract

Wearable technology constitutes a pioneering and leading innovation and a market development platform worldwide for technologies worn close to the body. Wearable optical fiber sensors have the most value for advanced multiparameter sensing in digital health monitoring systems. We demonstrated the first example of a fully integrated optical interrogator. By integrating all the optical components on a silicon photonic chip, we realized a stable, miniaturized and low-cost optical interrogator for the continuous, dynamic, and long-term acquisition of human physiological signals. The interrogator was integrated in a wristband, enabling the detection of body temperature and heart sounds. Our study paves the way for the development of watch-sized integrated wearable optical interrogators with potential applications in health monitoring and can be directly exploited for the customized design of ultraminiaturized optical interrogator systems.

A Concise Review of the Progress in Photonic Sensing Devices

“…A 4 × 1 long-wavelength VCSEL array, a 1 × 8 AWG edge coupler, a 2 × 2 MMI coupler, a 2 × 1 combiner, a 4 × 1 fiber grating coupler array, an integrated 8-channel Ge-on-Si WG PD array, straight WGs, and bend WGs were all included in the PIC, which had a size of roughly 2.5 mm 1.35 mm. The light source array is made up of four VCSELs with center wavelengths of 1545.34, 1548.53, 1551.33, and 1552.15 nm [135]. The findings of this work may be immediately used in the specialized design of ultra-downsized optical interrogator systems and open the way for the creation of integrated wearable optical interrogators the size of watches that may find use in health monitoring.…”

“…An earlier s has focused on specific technical domains of the wearables field, such as smart se [125,126], materials [127,128], and soft interfaces [129], or on the manufacturing and of such gadgets to concentrate on health conditions such as atrial fibrillation [130], c For enhanced multiparameter sensing in digital health monitoring systems, wearable sensors are the most advantageous. The first demonstration of a completely integrated optical interrogator is made [135]. For the continuous, dynamic, and long-term capture of human physiological data, an optical interrogator that is robust, compact, and inexpensive is produced by consolidating all the optical components on a silicon photonic chip.…”

Photonic Solutions for Challenges in Sensing

“…The instability of light source chips is also a challenge that could be solved by implementing C-band semiconductor lasers on functional substrates. 41 Sensors are currently sought to be portable, easy to use and interpret, even for nonexperts for point-of-care testing applications. 42 Photonic sensors have been equipped with automated operation and built-in sensorgram analysis software and tools allowing for easy miniaturization and portability.…”

“…Hence, flexible polymer optical fibers are more amenable to integration with soft textiles. The instability of light source chips is also a challenge that could be solved by implementing C-band semiconductor lasers on functional substrates …”

PLC-Based Arrayed Waveguide Grating Design for Fiber Bragg Grating Interrogation System

“…It can be used in aerospace applications, such as microgravity/orbital position monitoring, radiation measurement, and high-frequency vibration testing. Array waveguide grating (AWG) is the core filtering device of the FBG interrogation system, based on PIC technology, and demodulation using different interrogation methods, including edge filtering method [ 15 ], center-of-mass detection method, relative intensity method [ 16 ], etc. Among them, the relative intensity method uses two signals to demodulate an FBG wavelength and is theoretically independent of light source output optical power jitter, with relatively high accuracy.…”