Six elements of choosing an infrared thermal imaging camera

Six elements of choosing an infrared thermal imaging camera

1. Pixels

First of all, it is necessary to determine the pixel level of the infrared camera to be purchased. The level of most infrared cameras is related to pixels. The relatively high-end products in civilian thermal imaging cameras have pixels of 640*480=307,200. The infrared images taken by this high-end thermal imaging camera are clear and delicate, and the minimum size measured at 12 meters is 0.5*0.5cm; The pixel of the camera is 320*240=76,800, and the minimum size measured at 12 meters is 1*1cm; the pixel of the low-end infrared camera is 160*120=19,200, and the minimum size measured at 12 meters is 2*2cm . The higher the visible pixels, the smaller the minimum size of the target that can be photographed.

2. Temperature measurement range and measured object

Determine the temperature measurement range according to the temperature range of the measured object to select an infrared thermal imaging camera with a suitable temperature range. Most of the thermal imaging cameras currently on the market are divided into several temperature ranges, such as -40-120°C and 0-500°C. It is not that the larger the span of the temperature range, the better, and the smaller the span of the temperature range, the more accurate the temperature measurement will be. In addition, when the general infrared thermal imager needs to measure objects above 500°C, it needs to be equipped with a corresponding high-temperature lens.

3. Temperature resolution

The temperature resolution reflects the temperature sensitivity of an infrared thermal imager. The smaller the temperature resolution, the more obvious the infrared thermal imager perceives the temperature change. When choosing, try to choose a product with a small value of this parameter. The main purpose of the infrared thermal imager to test the measured object is to find out the temperature fault point through the temperature difference. It is not very meaningful to measure the temperature value of a single point. The main purpose is to find the relative hot spot through the temperature difference and play the role of pre-maintenance. .

4. Spatial resolution

To put it simply, the smaller the spatial resolution value is, the higher the spatial resolution is, the more accurate the temperature measurement is, and the smaller the spatial resolution value is, the smallest target to be tested can cover the pixels of the thermal imager, and the temperature of the test is the temperature of the measured target. real temperature.

If the spatial resolution value is larger, the spatial resolution is lower, and the smallest target to be tested cannot completely cover the pixels of the infrared thermal imager, and the test target will be affected by its environmental radiation. The test temperature is the temperature of the measured target and its surroundings. The average temperature of , the value is not accurate enough.

5. Temperature stability

The core component of the infrared thermal imaging camera is the infrared detector. At present, there are mainly two kinds of detectors, namely vanadium oxide crystal and polysilicon detector. The main advantage of the vanadium oxide detector is that the MFOV (Measurement Field of View) of the temperature measurement is 1, and the temperature measurement is accurate to 1 pixel. AmorphousSilicon (polycrystalline silicon) sensor, MFOV is 9, that is, the temperature of each point is obtained based on the average of 3×3=9 pixels. The vanadium oxide detector has good temperature stability, long life and small temperature drift.

6. Combination function of infrared and visible light images

If the infrared image and the visible light image are combined and displayed, a lot of work will be reduced. The unknown hotspots in the infrared image can be judged based on the visible light image, and the automatic report generation will also greatly reduce the operation time.