Get Adobe Flash player


Health and physical condition of the human body can be ascertained by making suitable measurements on the physical, electrical, chemical and acoustic signals emanating from it. Any disease or injury causes one or more of these signals to differ from their expected normal form. Quite often information reflecting the functioning or malfunctioning of the underlying biological system is entwined in a complex manner in these signals and hence such information has to be extracted. Conventionally, many of these signals were ascertained in an invasive manner. For example, to obtain the constituents of blood, blood is extracted from a patient and details obtained through a chemical assay. Present trend is to obtain as much information as possible, through noninvasive means. This paper reviews the state of the art in noninvasive measurement of biological parameters that are clinically relevant through the use of appropriate optical sensors. Emphasis is given on the research outcomes of the group to which the author is associated with.


Prof. V. Jagadeesh Kumar

Professor of Electrical Engineering and Head, Central Electronics Centre,
Indian Institute of Technology Madras,
Chennai 600036,