Recently, optoelectronic technologies have attracted more and more attention in the field of diagnosis, treatment, and intelligence. In particular, portable and wearable technologies are rapidly evolving and extending their reach to critical applications of wellness and healthcare. The progress is driven by advances in optical technology, sensor technology, circuits, computing, wireless communications, signal processing, measurement algorithm, and data analysis. Portable and wearable technologies allow extending the monitoring into the community and have been used in many research and clinical applications, including monitoring of healthy, elderly, and frail individuals, individuals with neurological disorders, measuring levels of physical activity in disease-association studies, and developing behavioral interventions. Combined, portable, and wearable optoelectronics create unique capabilities of continuous behavioral and physiological monitoring at home and in the community.

The goal of this special issue is to highlight state-of-the-art applications of portable and wearable optoelectronics with focus on wellness and healthcare applications of the technology. High-quality research articles, short communication, and reviews are welcome. Of special interest is research work that seeks to address recent development on small-size and wearable medical optoelectronic technologies, biomedical sensor technology, clinical applications, measurement algorithms, signal processing, statistics, problems, and solutions in the framework of health care and wellness, as well as the relevant prospect on opportunities and challenges.

Potential topics include but are not limited to the following:

• Smart medical and biological imaging instrumentation and techniques
• Noninvasive physiological monitoring
• Wearable optical biosensors and sensor-related technology
• Healthcare and wellness
• Wearable optical biosensors and sensor-related technology
• Laser diagnostic and laser therapeutic methods and instruments
• Mobile health
• Light or/and electronic stimulation in medicine
• Mini-size intelligence in healthcare
• Measurement algorithm, signal processing, data analysis, and interpretation
• Recent advances in preclinical and clinical researches of mini-size optoelectronic technologies
• The clinical application case of above novel technologies
• The problem and solutions of applying above novel technologies