热释电零值探测器的设计与研究

Design and research of pyroelectric null detector

单一晶体盘构成的热释电探测器,其热释电信号的极性不受加热信号极性影响,只与晶体盘的极化方式有关。设计了一种热释电探测器,它由两个同样方式极化的晶体盘连接在一起组成,所以在连接处域的极性相反。该探测器的上电极用于吸收光辐射,下电极用于接收电加热。当光辐射功率等于电加热功率时,这两种加热方式产生的热释电信号相互抵消,探测器输出零值。该热释电零值探测器可以用于辐射的绝对测量。

The pyroelectric detector is comprised of single crystal plate. The pyroelectric signal generated by it is only determined by the polarization mode of the signal crystal plate but not the polarity of the heat signal. Thus, a pyroelectric detector has been so designed that the sensing element is comprised of two uniformly poled crystal plates joined together so that the polarity of the domains reverses across the junction. The front electrode of the detector is used for absorption of radiation and the black electrode for electric heating. The pyroelectric signals generated by these two kinds of heat are counteractive then a null output is obtained when radiation power is equal to electric heating power. The pyroelectric null detector can be used for absolute measurement of radiation.