Pyroelectric infrared-sensitive element and pyroelectric infrared detector

Abstract

The invention provides a pyroelectric infrared-sensitive element and a pyroelectric infrared detector. The pyroelectric infrared-sensitive element has the following three-layer structure: an upper electrode, a lithium tantalite thin film layer and a lower electrode; meanwhile, the upper electrode can also be utilized as an absorbing layer; therefore, problems that extended response time and reduced sensitivity in the prior art can be solved, wherein the problems are caused by increasing of the thickness of a sensitive element. In addition, the pyroelectric infrared detector comprises: a pyroelectric infrared-sensitive element; a pyroelectric compensating sensitive element; a preamplifier field effect transistor; an impedance matching resistance; a tube cap; an infrared filtering window, which is arranged at the top of the tube cap; a tube socket, which is arranged at the bottom of the tube cap; three tube pins, which are arranged on the tube socket; a circuit board, which is packaged in the tube cap; and two support bodies, which are installed on the circuit board. According to the invention, the pyroelectric infrared-sensitive element has advantages of simple structure, short response time, high sensitivity and strong anti-interference capability and the like.

Description

technical field [0001] The invention relates to an infrared detector, in particular to a pyroelectric infrared sensitive element and a pyroelectric infrared detector. Background technique [0002] In order to improve sensitivity and reduce noise, early photon-type infrared detectors must be cooled to a very low temperature of 70K-90K. Therefore, photon-type infrared detectors must be equipped with refrigeration devices and other related equipment, which not only makes detection The structure of the device becomes complicated, and the manufacturing cost will be greatly increased. [0003] The uncooled pyroelectric infrared detector can work at room temperature, which overcomes the fatal shortcoming that photonic infrared detectors must work at low temperature, greatly reduces the complexity of instrument components, and also improves the reliability of the detector sex and cost performance. For pyroelectric infrared detectors, the current responsivity, voltage responsivity ...

AI Technical Summary

Problems solved by technology

However, the existing pyroelectric infrared sensor is mainly composed of four layers: the front absorption layer, the upper electrode, the pyroelectric film and the lower electrode. The double-layer structure of the front absorption layer and the electrode will increase the thickness of the sensor, resulting in Increased heat capacity, resulting in prolonged response time and reduced sensitivity, especially when used in NDIR detectors that require high uniformity and high detectivity, thick film structure detectors will be further limited

The current infrared detectors still have problems: they cannot effectively absorb weak infrared radiation energy, and cannot avoid the influence of background light and ambient temperature fluctuations.

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