Hello, this is Teppei in charge of KOYO Orient JAPAN'S Product Division. Today, I would like to go over the exciting world of Far-Infrared Cameras and its uses. Let's get started!
Japan is without a doubt, the world's largest camera nation. There are renowned camera and lens manufacturers, and they are producing cameras with excellent performance. However, even with the same optical equipment, the story seems to be different for Middle and Far Infrared cameras. If we visit related booths at an exhibition, most of them are industrial cameras from overseas manufacturers. Very few are made in Japan. Why is this the case?
According to a representative from an overseas manufacturer, it seems that mid-to-far infrared cameras are an industry that progresses closely in relation to the military, and research is progressing in the United States, France, and Israel. In Japan, there are various political situations.
Now, let's take a night vision scope as an example and go through the application examples of mid-far infrared cameras as they relate to the military, without any derailment.
First, a set of near-infrared light and near-infrared camera, which was introduced in the iPhone application example. If you take a picture of your opponent in this way, you can observe it without notice. This is the beginning of night vision scope. By illuminating the darkness with near-infrared light, you can find and attack enemies in an environment that looks bright and bright. It is wonderful.
But this has a major drawback.
If the opponent was watching with a similar near-infrared camera, the near-infrared light quickly turned into a brilliant target in the dark night. That makes no sense. After that, ultra-high-sensitivity visible light cameras that can be seen even in the slightest moonlight will appear, but breakthroughs have occurred in mid-far infrared technology.
As mentioned at the beginning, the mid-to-far infrared range is the wavelength range of the mid-infrared (2500 to 4000 nm) and far-infrared (4000 nm ~). Since the numbers are larger, the unit is not 2.5 nm, but generally 2.5 to 4 μm or 4 μm.
Heat is energy such as the vibration of atoms or molecules, and this wavelength range includes the frequency that resonates with this vibration. Vibration due to the heat of molecules is emitted as it is as mid-far infrared rays, and is absorbed and converted into heat.
The words often heard in commercials such as "warm warmth with the far-infrared effect." "Fire passes through the meat with the far-infrared effect." This is the characteristic of medium to far-infrared rays that transmits thermal energy. It It was a word that represents the.
In the case of observation using visible light to near-infrared light, there are not many objects that emit light by themselves, so the reflected light or transmitted light of objects illuminated by the sun or lighting equipment is usually observed. Obviously, you cannot observe the subject in a completely dark room.
However, in the mid-to-far infrared range, all objects emit mid-to-far infrared radiation unless they are at -273 ° C absolute zero. So you can observe in any darkness if there is only a temperature difference between the background and the subject. Thermography, which is sometimes seen on televisions, is an image obtained with a mid- to far-infrared camera. The world of the movie “Predator”!
It is very useful to be able to observe the heat itself. The body temperature of the creature, the engine of the vehicle, the firearm after foaming. Heat often contains important information on the battlefield.
I found an easy-to-understand video on how a mid-far infrared camera is effective as a night vision camera. See a comparison of images obtained with NIGHT VISION (probably a high sensitivity near infrared camera) and THERMAL (middle to far infrared camera).
Now, a mid-far infrared camera with such wonderful characteristics. One of the drawbacks is that noise suppression is very difficult.
Noise suppression from visible light to near infrared light is easy. If there is a place where extra reflection occurs, cover it with a black material that does not reflect. Our products are used for such purposes.
However, the story is troublesome when it comes to mid-far infrared light. What we observe is heat, but everything that is not the object of observation also emits heat. In other words, anything that is hot will be a source of noise. Even lenses and camera components.
If you make a camera with luminous materials, you can only shoot pure white images full of noise.
As such, the key to achieving high image quality with mid- to far-infrared cameras is to eliminate heat. One of the techniques taken is to take pictures while cooling the camera with liquid nitrogen. You can imagine it is a very large device.
However, the resulting image is highly accurate, and using the latest equipment, if the temperature difference between the atmosphere and the observation target is 0.1 ° C, it seems that a level of 100m can be created between a person 100m away from the atmosphere in the dark.
At present, with the advent of small cooling mechanisms such as Peltier devices, uncooled sensors, and advances in noise processing by software, the size, quality, and price of mid- to far-infrared cameras have been greatly advanced. Handy types that cost less than 100,000 yen are starting to appear. Mid-far infrared cameras have become very familiar.
There are various applications that can be applied by being able to visualize heat from the beginning, such as checking the thermal design of electronic circuits and finding water leaks on building exterior walls. In the future, it may be a tool that general companies and individuals can have. It is a fast growing product in the market in recent years.
Thank you for reading all the way. In summary, we have explained the applications and examples of the invisible infrared region. Did you enjoy it?
Koyo Orient Japan is a company specializing in products and services that mainly absorb visible to near-infrared light. The products we handle are black, and our sales vehicles are black. In a sense, it is a “black company”, but we want to continue to brighten the future of optics through our products.
If you are having trouble with internal reflection in near-infrared optics, please visit "FineShut SP" and "FineShut KIWAMI" pages. For reflection measures limited to the visible light range, please go to the "Flock Sheet" page.
Thank you for reading and have a wonderful day!