What’s the difference between 850nm and 940nm infrared LEDs?
The difference between 940nm and 850nm lies in the visibility. The infrared LED with 940nm produces no light and therefore cannot be seen by a human eye. Another thing is that the 850nm infrared light can illuminate a place better as compared to the 940nm. Also the operating voltage is different for both of them.
The 940nm infrared LEDs are virtually invisible (99%)to the naked eye. These LEDs produce virtually no light that the human eye can see. The light that comes from these, however, can be utilized by infrared cameras. The 850nm infrared LEDs is not as invisible as a 940. They have a very slight reddish glow to the LEDs themselves. The fact that they do have a very small amount of light that the human eye can see means directly relates to how well they can illuminate. A 850nm LED will illuminate better than a 940nm LED, all things being equal. The lower the NM number gives it better illumination ability. Operating voltage, amperage, manufacture and even actual size of the LED all play vital roles in the brightness and lifespan of an LED. This is how 48 LED and 28 LED (850nm) cameras can illuminate as well or better than 104LED (940nm) camera. If a camera has 940nm infrared LEDs it will be labelled as such in the description.
