Planck employs both HEMT radiometers as well as bolometer technology and will measure the CMB on smaller scales than WMAP.
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Langley invented the bolometer, an instrument for measuring infrared radiation, and used it on astronomical objects.
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An instrument that measures heat radiation; extremely sensitive
A bolometer is a device for measuring the energy of incident electromagnetic radiation. It was invented in 1878 by the American astronomer Samuel Pierpont Langley.
Infrared thermometer detector consisting of a resistance thermometer arranged for response to radiation.
Thermal detector which changes its electrical resistance as a function of the radiant energy striking it.
An infrared detector that functions by measuring the heating effect of the incident radiation
A device for measuring microwave or infrared energy, consisting of a temperature-dependent resistance used in a bridge circuit which gives an indication when incident energy heats the resistor. Used for indication when incident energy heats the resistor. ...
A sensitive resistance thermometer often used in IR instruments. Usually cooled with liquid nitrogen or helium to reduce dark currents.
Instrument for measuring the intensity of radiant energy. Its principle is based on the variation of electrical resistance, with the incoming radiation, of one or both the metallic strips which the instrument comprises.