应用案例

The laser aiming system and infrared temperature measurement system in an infrared thermometer are separate functions. A working laser therefore does not necessarily mean that the thermometer is measuring correctly. Low battery power, contaminated optics, condensation, unsuitable ambient temperatures, trigger-switch problems, detector failure, or internal circuit faults may all prevent a temperature reading from being displayed.

An infrared thermometer may still power on normally after being dropped, but this does not necessarily mean its measurement performance is unaffected. Mechanical shock can disturb the infrared optics, detector, electronics, or laser aiming system. This article explains what to inspect, how to perform a basic measurement check, and when the instrument should no longer be used for critical measurements.

Whether an infrared thermometer can measure through plastic film depends on the film’s transmission characteristics within the instrument’s operating wavelength range. A film that appears transparent to the human eye may still absorb or reflect infrared radiation. In many cases, the thermometer may primarily detect the film temperature or a combined radiation signal rather than the true surface temperature of the object behind it.

Shiny metals and other low-emissivity surfaces can strongly reflect ambient infrared radiation, making direct infrared temperature measurement unstable or inaccurate. Applying a piece of black tape with a relatively high and stable emissivity creates a more suitable measurement target. Once the tape reaches thermal equilibrium with the surface, it can provide a more reliable indication of the actual surface temperature.

Infrared thermometers can measure aluminum, copper, and other metallic surfaces, but shiny metals typically have low emissivity and high reflectivity. As a result, readings can be strongly influenced by reflected thermal radiation from the surroundings, causing temperatures to appear too low, too high, or unstable. This article explains the main challenges and practical ways to improve measurement reliability.

Stainless steel, particularly polished or shiny surfaces, often has low and variable emissivity and can strongly reflect infrared radiation from its surroundings. As a result, infrared thermometer readings may fluctuate or appear higher or lower than the actual surface temperature. Correct emissivity settings, controlled measurement geometry, reduced background reflections, and high-emissivity tape can significantly improve measurement reliability.

Metals—especially polished aluminium, copper, and stainless steel—often have low and variable infrared emissivity. An infrared thermometer may therefore receive not only radiation emitted by the metal itself, but also a significant amount of reflected background radiation. This can result in readings that are too low, unstable, or significantly inaccurate. Understanding emissivity, surface condition, and reflected radiation is essential for reliable infrared measurement of metals.

An infrared thermometer determines surface temperature by detecting infrared radiation through its optical system. If condensation, fog, or water droplets form on the lens or optical window, infrared transmission may be altered, resulting in low, unstable, or inconsistent readings. This article explains why condensation affects infrared temperature measurement, what causes it, and how to prevent and correct the problem.

When an infrared thermometer is moved from a hot or cold outdoor environment into a room, the instrument itself does not immediately reach the new ambient temperature. Its detector, optics, internal temperature sensor, and compensation circuitry may still be adjusting, and condensation may also form on the optical window. Allowing the instrument to thermally stabilize helps ensure more stable and reliable temperature measurements.

Infrared thermometers detect infrared radiation emitted from a target surface rather than relying on visible light, so normal bright light usually does not prevent them from operating. However, direct sunlight can heat the target, increase reflected-radiation effects on low-emissivity surfaces, and make the laser aiming point difficult to see. Understanding these factors helps improve the reliability of outdoor infrared temperature measurements.

Infrared thermometers can be used to measure objects in environments containing water vapor, but measurement reliability depends on steam density, optical path length, target temperature, the temperature difference between the target and the steam, and possible condensation on the lens. Normal humid air usually has limited impact over short distances, whereas dense visible steam can significantly interfere with infrared transmission.

Standard infrared thermometers generally cannot measure the true temperature of an object through ordinary glass because glass is not transparent to the infrared wavelengths used by most handheld instruments. The detector mainly receives infrared radiation emitted and reflected by the glass itself, so the reading is usually closer to the glass surface temperature. This article explains the measurement principle, influencing factors, and recommended measurement methods.