Infrared Thermometer FAQs
1. The relationship between the temperature measurement target size and the temperature measurement distance (the concept of optical resolution)?
It can be seen from the figure below that the effective diameter D of the measurable target is different at different distances, so pay attention to the target distance when measuring small targets. The definition of the distance coefficient K of the infrared thermometer is: the ratio of the distance L of the measured target to the diameter D of the measured target, that is, K=L/D
Figure 1 is the relationship between the temperature measurement target size and the temperature measurement distance
2. How to choose the emissivity of the measured substance?
Infrared thermometers are generally graded according to black bodies (emissivity ε=1.00), but in fact, the emissivity of substances is less than 1.00. Therefore, when the real temperature of the target needs to be measured, the emissivity value must be set. The emissivity of matter can be found from "Data on emissivity of objects in radiation thermometry".
3. How to measure the target in the strong light background?
If the measured target has a bright background light (especially when it is directly illuminated by sunlight or strong lights), the accuracy of the measurement will be affected. Therefore, objects can be used to block the strong light directly hitting the target to eliminate background light interference.
4. How to measure small targets?
aiming and focusing
Aiming: The small black dot in the eyepiece is the temperature measurement point, use the black dot to aim at the measured target
Focusing: The objective lens moves back and forth until the measured object is the clearest. If the diameter of the measured object is much larger than the small black dot, it is not necessary to adjust the focus. Please refer to the instruction manual for the specific method of focusing
When measuring smaller targets, for measurement accuracy
⑴ The thermometer should be fixed on the tripod (optional accessory)
⑵ Need to focus, that is: use the small black dots in the eyepiece to aim at the target (the target should be full of small black dots), adjust the lens back and forth, shake the eyes slightly, if there is no relative movement between the measured small black dots, then focus it's done
