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1、Chapter 8 Thermoelectric Detectors 第八章第八章 热电探测器热电探测器Light-heat-electricityTemperature-power relation, Thermoelectric effect http:/ Black body radiation 黑体辐射黑体辐射8.2 Temperature-power relation 热流关系热流关系8.3 Thermocouples and thermopiles 热电偶和热电堆热电偶和热电堆8.4 Thermistor bolometers 热电阻,测辐射热计热电阻,测辐射热计8.5 Golay

2、 cell 高莱元件高莱元件8.6 Pyroelectric bolometers 热释电器件热释电器件8.1 Black body radiation 黑体辐射黑体辐射Plancks formulaStefan-Boltzmann law) 1(),(/512TceecTM21621Wm1074. 32hccmK1043879. 122c4TMe42124214KWcm1067. 515ccffGkTTn)41 (4222220.11101000.0110100001E71E10 C 10000K 5000K 2000K 1000K 500K 200Khttp:/commons.wikime

3、/wiki/File:BlackbodySpectrum_loglog_150dpi_en.png 0510152025300100200300400500600700 300K 400K 450K 500K 550K0510012345 2000K 2500K 2856K 3000K 3300Kx10601230.01.21.5 8000K 8500K 9000K 9500K 10000Kx109Color temperature When we talk about blue light being cool and red light being warm

4、, we are referring to something very different from color temperature. We are using these colors to describe our perceptions or to convey moods. Counterintuitively, blue-hot is actually hotter than red-hot. The temperature of a Phoehoe lava flow can be estimated by observing its color. The result ag

5、rees well with measured temperatures of lava flows at about 1000 to 1200 C. /wiki/File:Pahoehoe_toe.jpgMeasurement of color temperature1. To measure the radiant energy over a spectral band. This gives a single intensity reading that is then converted to temperature. 2. To measu

6、re the radiation in two spectral bands and then take the ratio of the two. This two colour ratio is then converted to a temperature. http:/ Temperature-power relation 热热流关系流关系Heat transferhttp:/ GT0TtTTTGTCHdd)(d02211GT8.3 Thermocouples and thermopiles 热电偶和热电堆热电偶和热电堆http://wiki

7、/File:Thermocouple_circuit.svghttp:/www.msm.cam.ac.uk/utc/thermocouple/pages/ThermocouplesOperatingPrinciples.html where Emf is the Electro-Motive Force or Voltage produced by the thermocople at the tail end, T1 and T2 are the temperatures of reference and measuring end respectively, S12 is called S

8、eebeck coefficient of the thermocouple and S1 and S2 are the Seebeck coefficient of the two thermoelements; the Seebeck coefficient depends on the material the thermoelement is made of. Looking at above Equation it can be noticed that: a null voltage is measured if the two thermoelements are made of

9、 the same materials: different materials are needed to make a temperature sensing device, a null voltage is measured if no temperature difference exists between the tail end and the junction end: a temperature difference is needed to operate the thermocouple, the Seebeck coefficient is temperature d

10、ependent.http:/www.msm.cam.ac.uk/utc/thermocouple/pages/ThermocouplesOperatingPrinciples.htmlhttp:/ cooling A Peltier cooler, heater, or thermoelectric heat pump Peltier device, Peltier heat pump, solid state refrigerator, or thermoelectric cooler (TEC). /wiki/Thermoelectric_cooling8.4 Thermistor bolometers 热电阻,测辐射热计热电阻,测辐射热计http:/http:/8.5 Golay cell 高莱元件高莱元件http:/8.6 Pyroelectric bolometers 热释电器件热释电器件http:/ Wang Qingyou et al., Optoelectronic Technology, Publishing House of Electronics Industry0.01101000

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