ForeignersAfter a year, I understand Chinese mirrors
Mad Pill Research Institute, learn new knowledge every day In mythological stories, the Demon Mirror is known as an artifact that illuminates the true body of the evil spirit, and in the real history, although there are no demons and monsters, there is also a magical quasi-artifact-level mirror - the Western Han Magic Mirror.
This is a metal handicraft found in the ancient tomb of the Western Han Dynasty, made of a single piece of metal grinding, one side is engraved with relief patterns, the other side is smooth as a mirror, although it looks ordinary, but it is a witness to history, and the props in the costume TV series have the same historical value.
When the light hits the mirror, something amazing happens: the light reflected from the mirror hits the wall, revealing the shape of the pattern on the back of the mirror, as if the mirror itself is hidden in the wall.
It's amazing! Although the pattern on the back is not directly exposed to light, its shadow can be clearly reflected. What's even more surprising is that this solid piece of hard metal is able to transmit light, so that the pattern on the back is clearly visible.
This peculiar phenomenon surprised foreigners who saw it for the first time, and some even wondered if it was a mysterious spell. Some Chinese experts have also found that the mirror, which has barely been reproduced after the Han Dynasty, appears to be a unique technology patent.
It wasn't until the early 19th century, about 100 years after Westerners came into contact with this magical mirror, that they fully understood how the gadgets we made haphazardly thousands of years ago worked.
YouTube channel host Steve Mould recently explained in detail how this magic mirror, which contains the mysterious power of the East, works.
If we take a complete smooth flat mirror as a reference, then when the light hits it, it will be perfectly reflected.
If there is an exaggerated hole in the surface of the mirror, the light coming from all directions will be refracted into the distance and end up on the wall or screen.
If the large concave and convex are evenly distributed, can it form a pattern embossed on the back of the mirror? The answer is no.
There are two main reasons for this. First of all, if the pattern is formed in this way, then when we move the mirror itself, the image may disappear at a certain distance, or the reflected light will start to interfere with each other, causing the image to become blurry.
In reality, however, this did not happen.
No matter how far the mirror zooms out of the image, its shape remains the same. When you look closely at these patterns, you'll see that they're all made up of alternating dark and light edges.
However, it is difficult for such uneven undulations to form such a regular arrangement.
Steve changed his mind, turning the exaggerated depression of the mirror into a protrusion so small that it was barely visible.
Light is always keenly able to catch small changes, and the presence of edges and corners creates a dense effect on the reflected beam. If there is a wall on the opposite side that receives these reflections, then part of the beam will be more intense.
If you imagine a mirror covered with tiny bumps that match the undulating distribution of the patterns behind it, then you will find that the presentation of the image is no longer a difficult task.
However, this may explain why dark areas appear next to each other in the reflective pattern, but it does not explain why the pattern does not change much regardless of how the mirror moves.
According to this idea, the distance between the mirror and the wall will directly affect the image quality. For example, if the distance is too close or too far away, the image will be blurry before the light has time to disperse or gather.
Once again, the harsh reality ruthlessly overturns this assumption.
Although the problem is complex, the solution is as obvious as a convex mirror, quietly waiting for us to discover.
Yes, when the light hits the surface of the convex mirror, the mirror can effectively guide the light to reflect out, so that the whole mirror surface can get a good light distribution, so that the pattern is clearly visible.
Of course, this also covers some more esoteric mathematical principles, such as functions, calculus, etc., but the detailed elaboration may be confusing to everyone, so we will not go into details.
To sum up, the countless reflections of the mirror surface correspond to the slight bulge of the back pattern, and the convex mirror shape of the copper mirror as a whole can meet the requirements of imaging the back pattern.
Well, the principle of pattern formation is already clear, and it seems that an extremely precise process is required to achieve such a stunning effect. However, in the Han Dynasty thousands of years ago, how did the craftsmen of that time do it?
In fact, this does not require some extreme work on the part of the craftsman. During the casting process, the thinner part of the back pattern of the mirror cools faster than the thicker part, and it cools faster when polished, just like the thin part of the pancake is cooked first, and the thick part is cooked later.
Environmental factors such as temperature changes unconsciously make the shape of the mirror naturally blend with the pattern behind it, without any deliberate carving.
The surface of such mirrors can be so fine that it is almost impossible to distinguish changes with the naked eye.
Steve also left a wound on the mirror that was not visible to the naked eye, however, when the light shone through, the scar became clearly visible and undeniable as ironclad evidence.
Under the light, the tiny bumps on the mirror surface form ripples and flutters, and the visual effect is like ripples on the surface of the water. If these ripples are connected, the shape of the pattern on the back can be revealed.
After the Han Dynasty, why did similar mirrors become fewer and fewer? Perhaps it is because the mirror has gradually become a flat mirror, losing its previous unique reflective effect. At the same time, with the passage of time, the copper mirror also needs to be continuously polished, and the metal material will gradually wear out, which may inadvertently exacerbate the environmental factors such as cold and heat, and promote the copper mirror to form a unique pattern and form change, which is really a coincidence.
The secret of the Western Han Magic Mirror has been revealed, and various interesting patterns can be set on the mirror, making it a creative toy. Whether it's Einstein, a constellation or a villain, they can all become mirror elements.
Two thousand years later, the spark of ancient wisdom and modern innovation is exciting.
With a large screen and an efficient processor, you can experience a feeling of exhilaration.