| Dictionary, Encyclopedia and Thesaurus - The Free Dictionary 1,729,606,151 visitors served. |
|
Dictionary/ thesaurus | Medical dictionary | Legal dictionary | Financial dictionary | Acronyms | Idioms | Encyclopedia | Wikipedia encyclopedia | ? |
bolometer |
Also found in: Dictionary/thesaurus, Medical, Wikipedia, Hutchinson | 0.04 sec. |
|
bolometer (bōlŏm`ətər, bə–), instrument for detecting and measuring radiation radiation (rā'dēā`shən) ..... Click the link for more information. , e.g., visible light light, visible electromagnetic radiation . Of the entire electromagnetic spectrum , the human eye is sensitive to only a tiny part, the part that is called light. The wavelengths of visible light range from about 350 or 400 nm to about 750 or 800 nm. ..... Click the link for more information. , infrared radiation infrared radiation, electromagnetic radiation having a wavelength in the range from c.75 × 10−6 cm to c.100,000 × 10−6 cm (0.000075–0.1 cm). ..... Click the link for more information. , and ultraviolet radiation UV index predicts how long it would take a light-skinned American to get a sunburn if exposed, unprotected, to the noonday sun, given the geographical location and the local weather. ..... Click the link for more information. , in amounts as small as one millionth of an erg erg (ûrg), unit of work or energy in the cgs system of units, which is based on the metric system ; it is the work done or energy ..... Click the link for more information. . The bolometer was invented in 1880 by Samuel P. Langley. Basically it consists of a radiation-sensitive resistance element in one branch of a Wheatstone bridge; changes in radiation cause changes in the electrical resistance of the element. The radiation-sensitive element may be a platinum strip, a semiconductor film, or any other substance whose resistance is altered by slight changes in the amount of radiant energy falling on it. bolometer [bə′läm·əd·ər] (engineering) An instrument that measures the energy of electromagnetic radiation in certain wavelength regions by utilizing the change in resistance of a thin conductor caused by the heating effect of the radiation. Also known as thermal detector. Bolometer A device for detecting and measuring small amounts of thermal radiation. The bolometer is a simple electric circuit, the essential element of which is a slab of material with an electrical property, most often resistance, that changes with temperature. Typical operation involves absorption of radiant energy by the slab, producing a rise in the slab's temperature and thereby a change in its resistance. The electric circuit converts the resistance change to a voltage change, which then can be amplified and observed by various, usually conventional, instruments. Although bolometers are useful in studying a variety of systems where detection of small amounts of heat is important, their primary application remains as the instrument of choice for measuring weak radiation signals in the infrared and far infrared, that is, at wavelengths from about 1 to 2000 micrometers, from stars and interstellar material. See Barretter, Infrared radiation, Radiometry, Thermistor Bolometer A device for detecting and measuring small amounts of thermal radiation. The bolometer is a simple electric circuit, the essential element of which is a slab of material with an electrical property, most often resistance, that changes with temperature. Typical operation involves absorption of radiant energy by the slab, producing a rise in the slab's temperature and thereby a change in its resistance. The electric circuit converts the resistance change to a voltage change, which then can be amplified and observed by various, usually conventional, instruments. Although bolometers are useful in studying a variety of systems where detection of small amounts of heat is important, their primary application remains as the instrument of choice for measuring weak radiation signals in the infrared and far infrared, that is, at wavelengths from about 1 to 2000 micrometers, from stars and interstellar material. See Thermistor How to thank TFD for its existence? Tell a friend about us, add a link to this page, add the site to iGoogle, or visit webmaster's page for free fun content. |
|
| ? Mentioned in | ? References in periodicals archive | ||
|---|---|---|---|
| Researchers didn't have to wait anywhere near that long to detect the tell-tale alpha decays because the huge number of bismuth atoms in even a single bite-size bolometer crystal guarantees that some atoms will break down in a matter of days, if they break down at all, de Marcillac says. The effective efficiency of the two bolometer mounts was measured in the PSB calorimeter in Singapore in June and in the NIST calorimeter in July. The Fire Warrior employs a state-of-art bolometer to collect critical information and display it through a hands-free virtual imaging module developed by eMagin. |
| Encyclopedia |
| Free Tools: |
For surfers:
Free toolbar & extensions |
Word of the Day |
Help
For webmasters: Free content | Linking | Lookup box | Double-click lookup | Partner with us |
|---|