iTECH
New technology brings fresh ideas to the thermometers we
saw in iScience & iMaths, p6. Heat affects the movement of
electrons, for example, which modern technology can track
precisely.
DIGITAL THERMOMETERS
contain a heat-sensitive electric
resistor called a 'thermistor'.
Using computer technology
and semiconductor physics, the
temperature is measured and
displayed on a Liquid Crystal
Display, LCD.
LIQUID CRYSTAL THERMOMETERS
such as bendy forehead strips,
use thermochromic technology.
Think too of fun things like bath
toys that change shade in hot
water or the colourful magic of a
mood ring. As temperatures rise
and fall, these crystals change
colour – time after time!
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FUSE
FOREHEAD SCANNERS
('temple thermometers') use
infrared waves to scan inside the
body and accurately read the heat
emitted by your temporal artery.
'PILL THERMOMETERS'
(Ingestible Monitoring Systems)
were first developed in the
late 1980s to be swallowed by
astronauts! Nowadays they are
also used by Formula 1 drivers,
amongst others. This vibrating
'pill' includes a microbattery and
quartz crystal temperature sensor.
It sends out a low-frequency signal
that is interpreted by a signal
recorder outside of the body.
FIBER BRAGG GRATINGS
are a high-tech development
that reflect or even block certain
wavelengths in a short section of
optical fibre. They are now being
used in advanced temperature
sensors in risky areas like
seismology (earthquakes) and
nuclear power (monitoring the
core temperature and safety of
nuclear reactors).
From the Greek...
THERMOS + CHROMOS
= HOT + COLOUR
= THERMOCHROMIC