NEC's infrared cameras have a myriad of applications, from disaster relief to pandemic countermeasures
This time we will be discussing NEC's infrared cameras. NEC actually supplies products that use infrared technology, and the infrared cameras from affiliated company Nippon Avionics have apparently captured a large share of the market in Japan. I've heard that infrared cameras are put to use in a variety of situations, from disaster relief to measures for coping with pandemics.
But I get the feeling that a surprising number of people may not know what infrared cameras are, even if they've heard of them. So we went to talk to a developer of infrared cameras, and asked him questions on a range of subjects. Our discussion covers areas such as what infrared cameras are, what they are used for, and what unique technology NEC has applied to them.
An expert on infrared technology who has been involved in the development of infrared products since he joined NEC 27 years ago. He is also one of the key development team members for a new infrared sensor developed by NEC.
Infrared cameras capture images not visible using normal cameras
- MitaHello, Mr. Sasaki. Before asking you about infrared cameras, can you begin by explaining infrared rays in simple terms?
- SasakiLet me explain with this diagram (shows the diagram below). It indicates electromagnetic waves arranged in order of wavelength. See the area in the middle labeled "optical range"?
- MitaYes. There is a row of five lights from purple to red.
- SasakiThose indicate the light emitted from the sun that is visible to the naked eye. The electromagnetic waves with the longer wavelength to the right of the red light are infrared rays. As the diagram indicates, this light isn't visible to the naked eye.
- MitaI see.
- SasakiIncidentally, there are several types of infrared rays. Of these, NEC mostly deals with "far infrared" (long wavelength infrared), which has the longest wavelength. This light is less affected by the atmosphere, and incorporates a lot of temperature information in the region of 30 degrees close to our body temperature, making it a good candidate for use in infrared cameras that detect heat.
- MitaI'd like to ask about infrared cameras next. First, can you tell us how infrared cameras differ from normal cameras?
- SasakiTo start with, the normal cameras that people such as yourself use produce images or pictures by picking up reflected light from light sources such as the sun or an electric lamp. For that reason they are affected by the surrounding light, and cannot capture images when there is no light source. Meanwhile, infrared cameras are devices that detect the infrared rays emitted by objects and display them as an image. Consequently, they are not affected by the surrounding light, and can capture images whether it is day or night.
- MitaIt would be good to see a comparison of pictures or images.
- SasakiThen take a look at this (shows the image below). The images on the left were taken with a normal camera. The images on the right were taken with an infrared camera. They were taken at about the same place and time of day.
- MitaWow! The images on the left don't show up well at all, with some spoiled by the glare from lights, but the images on the right can be seen clearly!
- SasakiDoes that give you a better idea of how they are different? Because infrared cameras sense and visualize the heat given off by objects or people in this way, they can capture images clearly in places where there is no light, or where visibility is impaired by factors such as fog.
- MitaThe difference is staggering!
- SasakiInfrared cameras can also be used to quantify and visualize the temperatures that they detect. This is a technique called thermography. Temperatures are color-coded, making it easy to see at a glance where the temperature is high or low.
- MitaThey use color-coded pictures like those on TV sometimes as well!
- SasakiFor the record, in addition to enabling you to accurately measure temperature without touching an object, thermography also lets you efficiently measure the temperature of surfaces rather than points. Benefits such as this are put to use in a range of settings, such as on the manufacturing floor.
- MitaI think I'm gradually getting a better sense of the potential for infrared cameras!