The temperature measurement distance of a thermal imager is one of the standards considered by customers. Everyone hopes that the longer the temperature measurement distance of a thermal imager, the better. However, do you know the factors that affect the temperature measurement distance of a thermal imager?
1. Lens focal length
The most important factor determining the temperature measurement distance of a thermal imager is the lens focal length. The focal length of the lens directly determines the size of the image formed by the target. The larger the focal length, the farther the imaging distance, and the smaller the field of view angle. Simply put, as the focal length increases, the thermal imager can see further, but the viewing range (horizontal perspective) decreases.
To measure the temperature of an object using a thermal imager, it is necessary to ensure that the object exceeds 9 pixels in the thermal imager, otherwise the temperature measurement effect cannot be achieved.
2. Resolution
At present, the resolution of thermal imagers on the market is divided into five levels, 80 * 60160 * 120384 * 288640 * 4801024 * 768, among which the middle three levels are the most commonly used. As mentioned earlier, to measure temperature, it is necessary to ensure that it reaches 9 pixels. This indicates that resolution and temperature measurement range have a significant impact, and they are directly proportional to each other.
3. Detector performance
The focal length of the lens theoretically determines the detection distance of a thermal imager, and another factor that plays an important role in practical applications is the detector performance. The focal length of the lens only determines the size of the image and the number of pixels occupied, while the performance of the detector determines the image quality, such as blurriness and signal-to-noise ratio. The performance of detectors can be analyzed from aspects such as pixel size, thermal sensitivity, and signal processing. The smaller the pixel size, the smaller the spatial resolution and the larger the detection distance. The thermal sensitivity and signal processing of the detector determine the clarity of the image. If the thermal sensitivity of the detector is not high, the method of increasing the lens aperture is adopted to improve the image effect.