Temperature measurement using NIR camera with automatic adjustment of integration time for monitoring high-temperature industrial processes

Abstract

The system presented in this paper is based on a Near Infrared Radiation (NIR) camera to measure temperature above 300 °C. The CCD camera selected absorbs a small portion of radiation in the near infrared range, above λ = 700 nm. In addition, by using an NIR filter one can cut off the visible light to reduce noise and unwanted radiation. The system has been developed at the Institute of Applied Computer Science, Lodz University of Technology. This system has been made for controlling industrial thermal processes during the inductive heating hardening. The varying of camera integration time has been applied to avoid the saturation and to increase the sensitivity at low temperature. The emissivity of the inductive heating object has been taken into account. New algorithms for temperature calibration and image processing have been developed enabling measurement of temperatures from 300 °C, thanks to the application of automatic adjustment of integration time.

Keywords:

• NIR camera
• high-temperature industrial processes
• calibrated temperature measurement