Integrated Type Infrared Pyrometers | SIMTRUM Photonics Store

Basic composition

The structure of the IR pyrometer is designed around the logic of "capturing radiation - converting signals - processing and calculating - outputting results", and its core components include four major modules:

• Optical system: It is equivalent to an "infrared signal collector", composed of components such as lenses, mirrors or optical fibers. Its function is to converge the infrared light radiated by the object under test and focus it on the subsequent infrared detector, reducing the interference of ambient stray light and enhancing the signal strength.
• Infrared detector: The core sensing component, responsible for converting the infrared radiation energy gathered by the optical system into measurable electrical signals.
• Signal processing circuit: The electrical signals output by infrared detectors are usually weak and noisy. This module enhances, denoising, and digitizes the signals through amplification circuits, filtering circuits, A/D conversion circuits, etc. At the same time, it incorporates algorithms such as environmental temperature correction to eliminate the influence of external factors on the measurement.
• Display and Output unit: Responsible for presenting measurement results and achieving signal interaction.

Working principle

The core operation of an infrared pyrometer follows the fundamental law of thermal radiation: any object with a temperature above absolute zero (-273.15℃) will continuously radiate infrared rays (an invisible light) outward, and the intensity and wavelength distribution of the radiation are directly related to the temperature of the object.

According to Planck's law of radiation, the spectral distribution of an object's infrared radiation varies with temperature. The higher the temperature, the shorter the peak wavelength of the radiation and the stronger the total energy of the radiation. According to the Stefan-Boltzmann law, the total infrared radiation power per unit area of an object is directly proportional to the fourth power of the thermodynamic temperature, which is the key basis for the conversion between temperature and radiation energy. The infrared pyrometer captures the infrared radiation of the object being measured through an optical system. The infrared detector converts the radiation signal into an electrical signal, which is then amplified, filtered and compensated by the signal processing circuit. Finally, it is converted into the surface temperature of the object according to the preset algorithm and the reading is output through the display unit. Some models can also synchronously transmit the temperature signal to the control system.

The emissivity of an object (a parameter characterizing the object's ability to radiate infrared rays, with a value ranging from 0 to 1) directly affects the measurement accuracy. Therefore, most infrared pyrometers have an adjustable emissivity function and can be calibrated according to the characteristics of the material being measured (such as metals and non-metals) to ensure accurate results.

The reference table for the emissivity of common substances is as follows:

Confirmation of installation angles

To ensure accurate measurement, the Angle between the sensor's axis and the normal of the object being measured must be less than 45°. Due to the different measurement angles, the emissivity of the object being measured varies in a certain direction. Therefore, if the installation Angle changes, the emissivity needs to be reset.

Measurement of large-area high-temperature heat sources

When measuring large-area high-temperature heat sources, due to the scorching effect of the high-temperature heat source on the sensor, the temperature of the sensor will rise or change significantly and continuously, thereby affecting the measurement accuracy. At this time, a orifice plate can be installed in front of the sensor to block the heat source, which can improve the measurement accuracy and stability.

 

 

 

Product Dimensions

IRTSM3/5 series IR pyrometer	IRTSM3/5 series IR pyrometer external straight head connector
Schematic diagram of the installation bracket	IRTSX0 series IR pyrometer
Schematic diagram of L-shaped installation bracket