Flexible optical waveguides for health: a review of the current status and technological perspectives

Abstract

In response to the increasing demand for the prevention and control of chronic noncommunicable diseases, people are paying growing attention to the application of flexible optical waveguides in health assistance, and the specific functions of flexible optical waveguides are gradually enriched in the process. This review systematically explains the research progress of flexible optical waveguides in human health assistance. An analysis of the sensing principles used in flexible optical waveguides for signal sensing is provided. The specific applications of flexible optical waveguides in human health assistance are categorized into three main areas: invasive biomedical diagnosis and therapy, contact physiological information monitoring, and interactive soft robots. From the perspective of materials science, a comprehensive analysis is conducted on commonly used materials and their properties for flexible optical waveguides in human health assistance. Furthermore, the sensing principles and specific applications of flexible optical waveguides are provided, aiming to provide theoretical support and technological innovation direction for the construction of a new generation of intelligent health monitoring systems. The unique advantages of flexible optical waveguides in sensing, especially in human physiological signal sensing, are demonstrated through detailed theoretical analyses. Their specific applications in human health assistance are summarized under each category. Finally, this review proposes evolution paths for flexible optical waveguides by addressing current bottlenecks through material innovation (e.g., hybrids, metasurfaces), functional enhancement (e.g., self-powered sensing), and system integration (e.g., miniaturization, Internet of Things platforms).

Keywords

Flexible optical waveguide / sensing principle / invasive biomedical therapy / physiological information monitoring / interactive soft robot

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