Invention of the Evaporograph
For hundreds of years people have wanted a device that could take pictures in the dark. Modern scientists were also researching for such a device. A European war expert once said, “I wish I had a camera that could take pictures of the enemy in the dark! If it were possible, this war would have been won very easily and the war would have ended.”
Thermal Imaging Technology or Evaporograph
An American scientist said, “If only we could get a machine that could penetrate the darkness and take pictures and show them in light. If it was possible, we would know many secrets of this world." Many people from different professions in different countries were making various statements about the need for such a device. The scientists were investigating this matter with different types of cameras, big and small. Some cameras had very simple hinges and were very simple to use. Some were equipped with very fine equipment, but none could be photographed in the dark.
How can it be possible to take pictures in the dark?
First of all, light is needed to take pictures with a camera. In fact, if you want to understand the meaning of the word photograph specifically, you can understand the difficulty of trying to take pictures with a camera in the dark. The English word photograph is derived from the Greek words phos and graphos. The combined meaning of these two Greek words is painting with light. About nine hundred years ago, a Muslim thinker named Alhazen wrote the first description of the original method of photography with a camera. Four hundred years after these early accounts, Giambattista della Porta, an Italian, invented the first camera. Della Porta points out that if a lens is placed on one side of a closed box, then if an object is placed in front of the outside of the box, its shadow is produced and the shadow is reflected towards the inside of the box.
Many types of cameras have been invented since Della Porter's invention. There are also quite a few sensitive cameras available today. But none were able to take pictures in complete darkness. Except for the current night vision camera. While scientists had been working for years on the search for a camera to take pictures in the dark or a device to see in the dark, it became possible to take pictures with the help of newly invented devices other than cameras. X-ray machine is also an example of such discovery. X-rays are electromagnetic rays of high frequency that can penetrate the human body or any inert material. When this ray penetrates the body, it creates a shadow according to the depth of different parts such as internal bones and heart, lungs, arteries and veins.
When X-rays pass through an object, the shadow of the object falls on a photographic film to produce a shadow image. But this picture is a picture of shadow, not a photograph. Scientists have made many improvements to X-rays, but have not yet been able to produce color images in total darkness. With its help, scientists have tried but have not been able to take color pictures of objects near or far away in the dark. X-ray shadow images must be taken very close up.
At the beginning of the discussion of taking pictures in the dark, let's know about 'Radiation'. Because in this particular word lies our solution to the search for photography in the dark. Research on this radiant energy has been going on for a long time. In this way, every object radiates some energy and this fact was known to scientists long ago. Such as a piece of metal, a piece of stone, an ice wheel, even our body is radiating this energy. This energy is heat or infrared rays and it is possible to detect and control this energy with equipment. Some of the explorers who were trying to take pictures in the dark were attracted to this radiant energy. What kind of light energy is radiated to such an extent in the dark? By which it is possible to take a picture of the object from which the energy is being radiated? Can red eastern rays be used in such a way?
Radiant rays are longer than light rays and shorter than radio waves. Although these waves cannot be seen by the naked eye, they can be detected by instruments. Dr. Dollard, a scientist at John Hopkins University in the United States, famous for low-temperature research. H. Andrews and other scientists were also investigating this issue. Dr. Andrews, like many other chemists throughout the country, knew about devices that could "see" or detect the presence of an object in the dark. These devices are made according to Electron Theory and when they are operated in the dark, if any object emits rays in front of these devices, these devices record after receiving these rays.
Dr. Andrews invented such a device in his laboratory. Which will not only detect the presence of an object in the dark, but also show the object. This device is called Bolometer. This device captures infrared rays emitted by any object penetrating the darkness and reports the presence of that object. In fact, the device is effective with objects as close as five feet or as far as 15 miles away.
Can you see in the dark with a bolometer?
Imagine a man standing a few houses away. Bolometer (Bolometer) will show the presence of all those people on the screen of the device. Cars, trucks, carts can all be seen in the dark with the help of this device. But this instrument, in its simplest form, can see an object in equilibrium only in the sum of a few lines. These shadows need to be explained again; the development of the bolometer was greatly aided by those working on night vision cameras, but not a night vision camera bolometer.
Many scientists discussed the bolometer theory with Dr. Andrews. Further research on this continued. At this time, a German scientist named Dr. M. Czerny found the possibility of holding infrared rays emitted from an object in his laboratory with the help of a device and taking photos with the help of those rays. A scientist named Dr. Paul Overbo of the United States Air Force and another scientist named Dr. Walter Baird, president of the Board Atomic Society, collected all the above data and carefully described the infrared radiation for taking pictures in the dark. He started doing research. In this regard, Baird Atomic Society scientists conducted a series of experiments in their laboratories in Cambridge and Massachusetts. Finally their efforts were successful.
Dr. Baird and his assistants presented a unique device to the public on February 15, 1956. This technique requires no nuclear current, no visible light. This device can photograph a person 200 yards away or a house 1 mile away in total darkness. This device is called EVA. The common name of Evaporograph is EVA. The basic principle of EVA-device invention is derived from the radiation of red east rays; And with the help of Eva, the radiation from any object, large or small, located several miles away can be detected. Similar to EVA cameras in terms of function. Instead of light, it receives infrared rays emitted from an object and reflects those rays onto an oily film. As the infrared rays reach the parts of the oily film, the oil dries up and thus the image of the object slowly floats on the film. An image visible to the naked eye is created with the cone inside the EVA device. If necessary, pictures can be taken by attaching a camera to the device.
What does the image of a photograph taken on an evaporograph look like?
Image taken on the evaporograph
Evaporograph is a thermal imaging device made using the evaporation of a thin film of oil. An evaporograph image shows how much heat radiates from an object as it radiates from different parts of the object. If the temperature difference is greater, it appears brighter. Due to variation in temperature, the amount of infrared radiation is also reduced and this is why any image captured in the EVA device is in its shape. The EVA device is housed in a box measuring 18×14×11 inches. It looks very small, but its eyes can see even in the dark. If we open this box, we can see the working of EVA-machine in detail. Far-infrared rays enter through a lens, pass through a very fine device and fall into a concave mirror in a condensed state. The red eastern rays are filtered through a layer of salt before the rays are concentrated. Then the beam falls into an airless room and hits a plastic screen. The opposite side of the screen is coated with oil very thinly. From a distance, this screen looks like a small drop of oil has been released on top of a drop of water. When infrared heat falls on the screen, the screen heats up and dries the oil. At those points where intense and hot rays fall, it dries quickly and completely, and at those points where the rays are less intense and relatively cold, the oil dries slowly and less. Thus we see the image floating on the oily screen through the evaporograph with the naked eye or through the eye of the camera. An evaporograph is a thermal imaging device that works using the principle of differential evaporation (or condensation) in a thin film of oil. It is more sensitive than any thermal imaging method, especially when considering temperatures around 20°C.
Thermal imaging method of evaporograph
Infrared (IR) imaging: IR cameras detect thermal radiation and convert it into a heat map.
Thermocouple Imaging: Thermocouples measure temperature changes and convert it into a heat map.
Liquid crystal imaging: Uses liquid crystals that change color with temperature changes.
With the help of this invention, the commanders could take their pictures without the enemy's sight and increase the operational efficiency and win the war. Eva is able to capture tactical images of enemy positions and troops in their combat gear without being seen by the enemy. EVA can take pictures of a completely blacked-out city, where the heat of different parts of the city cannot be hidden. We learn that factories were set up underground for wartime production, but even these cannot be hidden from the oily eyes of EVA cameras. The heat from all these factories comes out from under the ground and is captured by this camera.
The invention of the evaporograph opened up many aspects of industrial and scientific research. Now with the help of Eva, many facts can be discovered at the same time about the temperature of the whole surface of a production pan or about the temperature of an electronic device. These inventions are capable of creating a list of how heat is generated in different parts of the interior of an appliance or how it is working. It is almost impossible to spot a metal fault with the naked eye, or even test it with an instrument. The EVA machine can handle such errors easily. Scientists are confident that an evaporograph can look inside a radio tube and quickly give an accurate reading of the temperature in different parts of the tube.
Advantages of Evaporograph
High sensitivity: can detect temperature differences of 1°C for temperatures as close as 20°C.
High resolution: can have a resolution of 10 lines per mm.
Non-invasive: No need to touch the sample.
Real-time imaging: Can collect data quickly and easily.
According to Professor F. H. Spedding of Iowa Test College in the United States of America, determining the heat of various objects was a great obstacle in the era of modern science. Dr. Spedding said that determining chemical reactions and metallurgical properties of objects at high altitudes was very difficult even in today's scientific age. It can now be said without a doubt that with Eva's invention it is possible to have knowledge of any temperature of matter of all kinds. Manufacturers of houses, offices, factories are active in finding out whether any part of these places emits heat. With the help of Eva's sensitive device, it can be detected in a few seconds if the heat is escaping in a house or industrial building. It shows where the heat is escaping from, and the heat escape path can be blocked with non-conductive materials as needed.
Principle of Evaporograph
Oil Membrane: A thin membrane is coated with oil.
Temperature difference: A temperature difference is created in the thin layer of oil on the membrane.
Evaporation: Oil evaporates faster in hot areas.
Condensation: Oil vapor condenses in the cooling zone.
Interferometry: Changes in film thickness due to evaporation and condensation.
Visible Image: This thickness change is converted into a visible image by the interference of light.
Its roots in medicine are also immense. Health is closely related to the temperature rise of the whole human body. The entire human body—the skin—is the first line of defense against germs. Doctors examine the skin of different parts of the patient's body at the beginning of a diagnosis. With the help of the evaporograph, the temperature variation of the body is detected very finely. This variation helps in diagnosis. Experts have already started planning to use the EVA device in herbal research and it is hoped that such research will reveal many new truths about human diseases.
What are the current uses of the Evaporograph?
Treatment: For diagnosis of skin cancer, vascular disease, and other diseases.
Industrial: For fault detection, heat distribution monitoring, and process control.
Environment: For oil pollution, groundwater seepage, and landslides.
Science: For thorough examination in fluid dynamics, surface chemistry, and physics and mathematics.
The steamer's officers thought that Eva's help could be enlisted in carrying out rescue operations in the event of a shipwreck. Because in the dark of night in the ocean, even in icy water, EVA will collect the body heat of people immersed in it to speed up the rescue operation. However, EVA is now used in conjunction with radar. However, the desire to know something new raises various questions in the minds of scientists. Find ways to innovate. These days there are frequent bank robberies by tunneling underground, or attempts to use the evaporograph to help solve other illegal crimes or in industrial production. In this way, such a camera that can see in the dark will be useful to people in everyday life and also to scientists who are searching hard to know the unknown. As Eva light will shed new light on chemistry and physics work and other scientific endeavors. Now Eva's eyes can see objects two hundred miles away in the dark of night. By connecting to the radar, the enemy's missile can be detected and destroyed in the air. It is also possible to see through flames. Not only that, the heat radiation of the sun can be observed by connecting it to the telescope. Earth's weather data can be collected with the help of this device by connecting it to artificial satellites.