In the contemporary aging society, one of the most serious social issue is increase in medical expenses and lack of medical professionals. To deal with this problem, fundamental system of medical service should be revolved. Although it is usual way that a patient start to consult the doctor after his or her subjective symptoms, early therapy based on early detection of physical abnormality should be promoted using continuous vital sign monitoring. Obviously, the monitoring is required to be safe and accurate. As well, it is indispensable to be inexpensive, easy, and stress free for real application of this idea. As one way, we study smart textiles for health care. Especially, optical fiber sensors are remarkable devices. That is to say, optical fibers are considered to be suitable for textile processes by their yarn- or fiber-like form. As a fundamental study, we discussed optical fiber embedding during weft knitting process. By covering optical fibers with textile yarns, the covered optical fibers are successfully introduced into fabrics during inlay knitting process.
