A "transfer picture" for monitoring blood flow and skin condition
Researchers at Northwestern University and the University of Illinois have developed a miniature device designed for permanent wear that immediately informs a person about heart problems or the need to apply a moisturizer to the skin.
The wireless sensor is a square with a side of 5 cm that is glued to the skin of the wrist. It consists of a thin flexible base, on which 3,600 liquid crystals of 0.5 mm in size are applied, reacting to changes in the temperature of the skin. A change in the color of the sensor signals a person about problems in the body.
The technology developed by the authors uses transient changes in skin surface temperature to determine the blood flow rate, reflecting the state of the cardiovascular system and the degree of hydration of the skin (dehydration changes its thermal conductivity).
Each crystal changes the temperature independently of the others, which provides data on the temperature distribution over the entire area of the device, and a special algorithm transforms the temperature data into an accurate health report. The whole process takes no more than 30 seconds.
A large number of liquid crystals provides a high degree of spatial resolution comparable to the indicators provided by infrared radiation sensors used in medical practice.
Unlike expensive infrared sensors, the use of which is possible only in the clinic, the new device does not require large financial costs and can be used in almost any conditions. It also has a wireless heating system activated by electromagnetic waves and designed to determine the thermophysical properties of the skin.
Article by Li Gao et al. Epidermal photonic devices for quantitative imaging of temperature and thermal transport characteristics of the skin is published in the journal Nature Communications.
Evgeniya Ryabtseva
Portal "Eternal youth" http://vechnayamolodost.ru based on the materials of Northwestern University:
‘Skin-Like’ Device Monitors Cardiovascular and Skin Health.
26.09.2014