InGaAs avalanche photodiode thermometry

Abstract

The infrared detector is the most important component within any radiation thermometrybased system, with its choice determining the wavelength, response time and, ultimately, the temperature measurement capabilities of the instrument. To improve upon the existing generation of radiation thermometers, more sensitive detector technologies are required. In this work, we demonstrate a direct comparison between an indium gallium arsenide (InGaAs) photodiode and an InGaAs avalanche photodiode (APD) for 1.6 µm radiation thermometry. The high internal gain of the InGaAs APD increases the sensitivity of the radiation thermometer, enabling the measurement of a target temperature more than 50 °C lower than is typical with commercially available InGaAs photodiode thermometers. The more sensitive InGaAs APD provides faster response time measurements, hence improving the thermometer's temporal resolution. Finally, the InGaAs APD is shown to produce a quantitative thermal image with lower measured temperature fluctuation across the scene when incorporated within a highly aperture limited scanning system.

Design of Lidar Receiving Optical System with Large FoV and High Concentration of Light to Resist Background Light Interference

“…In addition, the pulse width of the emitted laser is only a few ns, so a very fast response speed and response bandwidth are required for the subsequent signal readout circuit, which is another great challenge [ 9 , 10 , 11 ]. On the other hand, the single-element gaze receiving system has a simple structure, which can greatly simplify the design of the system and achieve miniaturization.…”

Special Section on TEMPMEKO 2019: a feature on the XIV International Symposium on Temperature and Thermal Measurements in Industry and Science & IV International Temperature Conference, Beijing (TEMPMEKO & TEMPBEIJING 2019) and Metrology for Meteorology and Climate (MMC 2019)

“…Pearce et al [4] describe the lifetime extension of Type R and Type S thermocouples by doping the Pt leg with zirconium, which not only restricts grain growth that can lead to breakage, but also counteracts drift due to rhodium contamination by an increase in emf when zirconium is converted to an oxide. Hobbs and Willmott [5] investigate the application of InGaAs avalanche photodiodes to radiation thermometry. Optimizing the sensor reverse bias voltage to obtain the best signal to noise ratio enables the low temperature measurement limit to be 50 • C lower than with a regular InGaAs photodiode.…”