There are a lot of sensors, like Oxygen sensor, temperature sensors,
CO sensor and so on. But do you know what the sensors used in the
temperature measurement, and how do the temperature sensors work.
Temperature sensors from ISweek.com
Most common sensors for temperature measurements: Thermistors - whose resistance changes with temperature Thermocouples - which use different metals in contact to create a small voltage potential proportional to temperature Infra red sensors that measure thermal IR emissions for non-contact sensing Various bi-metal sensors that physically change shape due to coefficient of expansion differences; the mechanical movement is measured and converted to a signal.
There are many more way s to measure temperature. I work on optical sensors that used fine Bragg gratings. Bragg gratings are tiny etchings in the side near the end of a long optic fiber that make a high-Q reflector at the wavelength of the spacing. The Bragg grating is therefore a wavelength dependent reflector. We use a tunable laser to sweep past the wavelength range of the grating. As the fiber is heated or cooled, it expands or contracts effectively changing the wavelength of the gratings. We can therefore determine the precise temperature at the grating location by the wavelength of the laser light it reflects. This can be done with the laser at a distance of ten thousand or more meters from the sensor in conditions that electronics don't work well (like at the bottoms of oil wells).
Source: iSweek（http://www.isweek.com/）- wholesale sensors & transmitters
Most common sensors for temperature measurements: Thermistors - whose resistance changes with temperature Thermocouples - which use different metals in contact to create a small voltage potential proportional to temperature Infra red sensors that measure thermal IR emissions for non-contact sensing Various bi-metal sensors that physically change shape due to coefficient of expansion differences; the mechanical movement is measured and converted to a signal.
There are many more way s to measure temperature. I work on optical sensors that used fine Bragg gratings. Bragg gratings are tiny etchings in the side near the end of a long optic fiber that make a high-Q reflector at the wavelength of the spacing. The Bragg grating is therefore a wavelength dependent reflector. We use a tunable laser to sweep past the wavelength range of the grating. As the fiber is heated or cooled, it expands or contracts effectively changing the wavelength of the gratings. We can therefore determine the precise temperature at the grating location by the wavelength of the laser light it reflects. This can be done with the laser at a distance of ten thousand or more meters from the sensor in conditions that electronics don't work well (like at the bottoms of oil wells).
Source: iSweek（http://www.isweek.com/）- wholesale sensors & transmitters
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