The thermal imager uses the infrared detector and the optical imaging objective lens to receive the infrared radiation energy distribution pattern of the measured target and reflect it on the photosensitive element of the infrared detector to obtain an infrared thermal image. This thermal image and the thermal distribution of the surface of the object The field corresponds. Generally speaking, a thermal imager is to convert invisible infrared energy emitted by an object into a visible thermal image. The different colors on the top of the thermal image represent different temperatures of the measured object.

Today, Wuxi very Xiang Technology Co., Ltd. takes you to understand the three index resolutions of infrared thermal imager :

Spatial resolution

Spatial resolution refers to the resolving ability of the infrared thermal imager to the shape of the target space when using an infrared thermal imager for observation. Generally speaking, the smaller the spatial resolution is, the more accurate the temperature measurement is. When the spatial resolution is small, the measured target covers the pixels of the infrared camera, and the test temperature is the temperature of the measured target; the higher the spatial resolution is If the measured target cannot completely cover the pixels of the infrared camera, the test target will be affected by its ambient radiation. The test temperature is the average temperature of the measured target and its surrounding temperature, and the value is not accurate enough. The spatial resolution of an infrared camera is usually expressed in mrad (milli-radians). The smaller the value of mrad, the higher the resolution. The radian value multiplied by the radius is approximately equal to the chord length, which is the diameter of the target.

Image Resolution

The resolution of the map actually refers to the number of pixels of the thermal image. The higher the resolution of the thermal map, the more pixels are imaged, which means that the more temperature measurement points, the more accurate the temperature measurement will be.

Temperature resolution

The thermal resolution of a thermal imager refers to the ability of an infrared thermal imager to accurately distinguish the smallest temperature difference of the target radiation from the background.

A smaller temperature resolution means that the infrared camera will be more aware of temperature changes. The netd (noise equivalent temperature difference) is usually used to express this performance index. For example: netd = 50mk, which means that if the surface temperature of the measurement object changes by 50mk, the camera can detect the change. The main purpose of the infrared camera to test the measured object is to find the temperature failure point through the temperature difference. It is not very meaningful to measure the temperature value of a single point. It is mainly to find the relative hotspots through the temperature difference and play a pre-maintenance role. .