What are some suggestions for purchasing infrared thermal imaging night vision devices for research and development?
Point 1:
What temperature are you measuring?
A common application of thermal imaging cameras is to measure temperature changes in the object under study. Two points to consider when measuring temperature are: the temperature range of the object being measured and the desired temperature resolution. Answering these two questions will help you narrow down your choices to the type of thermal imaging camera and detector that best suits your needs.
temperature range:
The temperature range measures how cold or hot an object will be. This may also be the lowest or highest temperature you can measure. For example, you're photographing the engine of a plane parked on a runway. The temperature of the fuselage of the aircraft may be around 25°C, while the temperature of the engine is about 500°C. So your temperature range is about 25°C to 500°C, then you need to choose a thermal imaging camera system that can capture the entire temperature range at one time.
Temperature Resolution:
Temperature resolution is the smallest temperature difference you need to measure and is often referred to as the thermal sensitivity of your infrared camera. Depending on the thermal imaging camera detector type, the thermal imaging camera's thermal sensitivity can range from less than 0.025 °C to less than 0.075 °C.
The temperature resolution or sensitivity of an infrared camera is often referred to as the Noise Equivalent Temperature Difference (NETD). This parameter is the smallest temperature difference that an infrared camera can detect above its noise floor. Simply put, this is the smallest temperature difference you can detect with a particular camera. Table 1 shows common temperature ranges and temperature resolutions for different models of thermal imaging cameras.
Point 2:
How fast do you need to capture data?
Answering this question requires consideration of three factors: exposure time, frame rate, and total recording time.
exposure time
Exposure time refers to the speed at which an infrared camera captures a single frame of data, which is similar to the shutter speed of a traditional visible light camera. The exposure time of an infrared camera is referred to as the integration time, or thermal time constant of the detector. Both terms refer only to the time it takes to capture a thermal image.
Now, let's make an analogy to the exposure time of a thermal imaging camera, i.e. compare the advantages of conventional cameras with longer or shorter exposure times. For both cameras, the shorter the exposure time, the less likely the image will be blurred when capturing high-speed moving events. However, due to the shorter exposure time, the thermal imager has less time to capture the target; therefore, underexposure may result. On the other hand, if the exposure time is longer, more light (for conventional cameras) or heat (for thermal imaging cameras) can be collected from the object of interest. Of course, the disadvantage is that if the target is moving fast, the image may become blurred.
So there is a balance between short exposures and long exposures. However, according to Table 1, we know that the higher the thermal resolution of some thermal imagers, the higher their thermal sensitivity. From this we can deduce that when observing the same thermal target, the same image is taken In general, a thermal imager with high thermal sensitivity requires a shorter exposure time than a thermal imager with low thermal sensitivity. For thermal imaging cameras with higher thermal resolution detectors, we can kill two birds with one stone: high-quality images of cooler targets without motion blur.
