Color-changing card?

Draped raster painting?

The first thing that comes to the students' minds is that when they were young, they played with a card toy that could see different images from different angles. Pen | fun | pavilion www. ｂｉｑｕｇｅ。 ｉｎｆｏ

But soon this conjecture was overturned, and the font on the iron ruler was not flat at all. Instead, it was chiseled into the iron ruler, and the traces of the depression could be clearly seen.

"Friends... "Professor Kobayashii's eyes are like firewood burning helplessly in a raging fire.

There is nothing abnormal on the front, and you can see the font from another angle.

What does this mean?

It shows that the four words on the iron ruler, between the strokes and the depictions, are unimaginable horizontal and vertical.

Its principle is simple to explain, if a piece of paper as thin as a cicada's wing, the sides are horizontal and perpendicular between the eyes, then it can easily disappear.

Similarly, the bottom of the font that is recessed on the iron ruler should maintain the same roughness as the surface. This effect can be achieved by machining the side to a frighteningly accurate straight line.

It's easy to explain, but it's very difficult to do.

In the live broadcast room, after the science popularization of a knowledgeable mechanical expert, the students invariably brushed 666 in the barrage......

"Haha~ Just now on the side of the Japanese Institute of Technology, I insisted that there was nothing, but I was slapped in the face from a different angle. ”

"It's so cool, just rush to this visual effect, and you can compare that nut to it. Aren't they invisible, but the threads are as thin as silk. And our four words are as big as mahjong, and the difficulty is naturally much higher. ”

"Is that the only one, this classmate?" Kobayashii said in a relaxed sentence, which made the barrage and the students below suddenly quiet.

"Great ideas, admirable machining accuracy. ”

"But in our opinion, this gift, the level of industry it represents, is still a little short of the top manufacturing technology. ”

It is not arrogant, the technology shown by this iron ruler, Professor Kobayashii, borrowing from a well-known domestic high-precision instrument factory, can also be manufactured.

Of course, there is difficulty, and it will take a lot of time, but it will not be difficult for him.

"It's over, look at this guy's confident look, it seems that they can also make this kind of magical lettering. ”

"After all, they are the world's first in precision machining technology, and it is understandable that they can't help it. ”

"Alas~ Although it is not difficult, it is not a loss. ”

In the live broadcast room, the discussion resumed.

"Professor Kobayashii, I think you misunderstood me. Ye Qing raised the iron ruler in Yang's hand and turned the other side.

"At the beginning, you gave us a nut to make a screw. ”

"Then we naturally want to return the favor and give a commemorative gift that requires the cooperation of our two schools to be complete. ”

After a pause, Ye Qing was very satisfied with the deflated expressions of the guys on the other side.

After showing the iron ruler at different angles and confirming that the reverse side of the iron ruler did not have any Chinese characters, Ye Qing's eyes were calm: "The friendship for a long time is a blessing we send to your school." ”

"I would like to ask your school to engrave another sentence in your language on the reverse side of this iron ruler to testify to our friendship. ”

"Engrave a sentence?" Xiao Linjing didn't react a little: "Engrave a sentence?"

"What to engrave, the answer has been written on the iron ruler, you only need to decipher it, and then use your words to engrave it. ”

After speaking, Ye Qing handed the iron ruler to Xiao Linjing.

The camera clearly captured the suspicious look on Xiao Linjing's face, and the moment he took over the iron ruler, his right hand obviously sank down, revealing why it was such a heavy expression.

The students of the Japanese Institute of Technology gathered around in an uproar.

Here's the highlight, it turns out that this iron ruler not only has amazing precision machining technology, but also hides a puzzle for them to solve.

Fortunately, the Japanese University of Science and Technology had already prepared, and at noon Professor Cai informed them that he would give an iron ruler as a gift. They kept speculating about what this iron ruler would be.

Therefore, many of the town's sub-instruments that originally needed to be packed into shockproof metal boxes and packed away were also brought to the multimedia center.

The iron ruler is more than 30 centimeters long, and there is not even a scale on it. Kobayashii believes that even if there is a mystery, they can easily solve it.

This self-confidence stems from the equipment they carry.

A Nikon S1500 industrial electron digital microscope was moved to the desk by the students of the Japanese Institute of Technology.

Nikon Corporation is one of the world's top optical lens factories. The microscope they took out is currently the microscope with the highest effective magnification among the optical microscopes, and there is no one.

Hmph~ Any cat, under this top-of-the-line optical microscope, there is nowhere to hide.

However, when the students of Polytechnic University set up their microscopes and turned their eyes to the liquid crystal display on the microscope.

Their reaction was more exaggerated than the detonation of a grenade.

With a sudden, they took a step back.

"This can't be!" shouted Kobayashi in his native language, "why is it flat on the surface?"

The other students probably also had a ghostly expression.

Because when they had just adjusted the magnification to the best observation factor of 1,200 times, they saw that the surface of this iron ruler was still smooth. Although it is not as flat as a mirror, it is similar to the surface of ordinary steel when viewed directly with the naked eye.

The first step in studying a metal is to study its characterization.

Magnifying 1,200 times, you can directly see the microstructure of the metal surface, such as the snowflake-like martensite and austenite on the metal.

In the same way, when they looked at this iron ruler with the naked eye, they did not find any cats, so they naturally thought that it was hidden under a microscopic mechanism that was invisible to the naked eye.

What did they see?

If we talk about the previous lettering, for them, it can be called a difficult processing technology. The smooth representation of this iron ruler is equivalent to fear-level processing technology.

It took a lot of effort for them to suppress the fear in their hearts and continue to study the iron ruler.

Time passed little by little, and the Japanese University of Science and Technology, who had already flown to Siberia with pride, changed to dignified and crazy.

Because they can't find anything, no matter how they observe. The surface of this iron ruler is all flat, not to mention the greasy puzzles, and not even a single spot that is not black can be found.

"Haha~ Look at their tangled looks. ”

"Stumped, let them look down on us again?"

"I think...... They need Detective Conan to save the day!"

Half an hour had passed, and Xiao Linjing raised his head with difficulty, his face was full of beads of sweat: "Warp ...... After our unanimous study, there seems to be no mystery on this iron ruler. ”

"Yes. Ye Qing's unhurried answer made the students of the Japanese Institute of Technology almost miserable.

"Have you measured the length of this iron ruler?"

"Yes...... It has been measured. Kobayashi took out a hand-held rangefinder: "This is a rangefinder produced by Nikon, and we have measured not only the length, but also the width and height." ”

"Its length is 0.32569 meters. ”

"The ruler energy is long, and the answer lies in its length. Ye Qing stood up and shook his head: "The accuracy of the rangefinder is not enough, you can change to a more advanced instrument to re-measure its length." ”

"But we've been accurate to the centimeter, and it's too long for a micrometer to measure. If you want to be more accurate, you need to use a laser interferometer. ”

"What level of accuracy can your laser interferometer be?"

"Nanoscale. There was a hint of roar in Kobayashii's voice: "We can be accurate to 2 nanometers, but what's the point of measuring this iron ruler?"

"With an accuracy of two billionths of a meter, there is no machine tool at this stage to process it. Even our industrial machine can only determine the accuracy of metal materials at 50 nanometers. ”

"0.32569 meters?" Ye Qing said with a serious gaze.

"What do you mean? This length, we measured it. ”

"There's 734 in the back. Ye Qing looked at him and reported a number.

Kobayashi Jing said with some disbelief: "You have accurate to 0.1 filament?"

"Since your laser jammer can't meet the accuracy standard, then I'll tell you the accurate answer. ”

Ye Qing said calmly: "We have fixed the accuracy on one-half nanometer, that is, the accuracy of five billionths of a meter. ”

"The ruler energy is long. ”

"If you are in a vacuum box, use a more advanced jammer to measure the length of this iron ruler. ”

"You will get such a set of numbers 0.32569734830, a very simple set of decimal numbers, as long as you replace this set of numbers with your text, you can get the words you want to engrave on it. ”

Quiet.

In the multimedia center, the old man dropped a time bomb, which made their expressions freeze instantly.

Convert the length of the ruler into their words?

Derives ......

What are they going to engrave? )