Chapter 410 Chief Engineer Gao, we are ashamed!

This made Qin Huairu cry. After her husband left, the neighbors in the yard, except for a few, did not abandon their widow and orphan.

Seeing Qin Huairu about to cry, Sha Zhu couldn't sit still anymore: "Sister Qin, don't be like this, this is a happy event, why are you crying? Zhendong's family doesn't need these, just accept them for the child."

Gao Zhendong glanced at Sha Zhu with a half-smile, this kid.

After seeing Qin Huairu off, Gao Zhendong and his wife had another meal with Sha Zhu. The couple were busy packing up in the morning and did not cook.
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While Gao Zhendong was finishing up the operating system and waiting for Lou Xiao'e to start school on September 9, he encountered another group of people who arrived first.

Two comrades from the original research institute came to see him, holding a letter of introduction for the Defense Work Committee’s vehicle.

The moment they saw Gao Zhendong, the two comrades were quite excited as if they had finally met the real person. Although they were a little older than Gao Zhendong, they still modestly called him "Teacher Gao".

This really put Gao Zhendong on edge, and he quickly said, "Comrades, you can call me Gao Zhendong, or Comrade Gao, or Chief Engineer Gao. I cannot bear the title of 'Teacher'."

He knows his own business best. When it comes to lasers, I'm afraid I'm not qualified enough to be a "teacher".

The two comrades did not listen to him: "Teacher Gao, you are wrong. A pioneer is a pioneer. This cannot be faked. Even if you no longer work in this profession, we still have to have this little courtesy."

After a long argument, Gao Zhendong finally won. "Since you want to call me teacher, then just listen to me and call me by my title."

After the two sides talked for a long time, Gao Zhendong asked about their purpose.

The two men came here for one thing only, the laser gyroscope.

Gao Zhendong had thought that the laser gyroscope would be made in the desert, but after listening to them, he felt that it made sense. If they had to do everything in the desert by themselves, then they would have nothing to do. Even if the people there were made of iron, they wouldn't be able to hammer a few nails.

Actually, Gao Zhendong only knew so much about the laser gyroscope up to now. The two men seemed to be asking for advice humbly, which made him feel a little uneasy.

But he was not afraid, because he had food in his hands and was not panicked.

After four consecutive draws in early July, there were 7 chances left, and now 5 more have been added. One of them was used to draw the "Barefoot Doctor's Handbook", so there are still 8 chances left. Don't panic.

I didn’t read many books in my previous life, but I did save quite a few.

"What do you want to ask? Regarding the principle, I should have already told the comrade who came last time. As for the details, I won't know if I can answer them until you ask me."

The comrades from the original research institute did not know who the comrade who came last time was, and Gao Zhendong did not say either.

However, they were well prepared for Gao Zhendong's words. As emerging professionals in the field of laser, they had made a lot of preparations to meet Gao Zhendong.

"Mr. Gao, after some preliminary theoretical calculations, we found that in terms of principle accuracy, it is difficult to achieve the accuracy you mentioned when measuring optical path difference using optical interference. Although the theoretical accuracy calculated can be used, it is far from the level you mentioned. In other words, we are stuck at the first step."

This first question shows that these two comrades are really professional. In front of Gao Zhendong, they may be a little timid in terms of laser, but their foundation in optics is indeed solid.

As the two comrades spoke, they handed their calculation process to Gao Zhendong, as if they wanted him to correct them.

With this calculation process in hand, Gao Zhendong is no longer planning to save on the number of draws.

System, search for me!

The result was as he expected. The results of his argument with netizens were very fruitful. A professional textbook on laser gyroscope published in the 80s appeared in his storage repository, and it was published by Wudaokou.

He has spent it 4 times, and doesn’t care about the remaining one. After all, he is going to use part of it soon, so he wrote it to me!
Looking at the pile of manuscripts in his own handwriting in the storage library, Gao Zhendong felt quite pleased with himself.

The two comrades from the original research institute felt nervous when they saw Gao Zhendong carefully looking through his calculation manuscripts. They didn't know how he would do on this first test paper under the personal guidance of the founder.

They thought Gao Zhendong was reading his manuscript because he was talking to them while reading it.

In fact, Gao Zhendong was looking through a book on laser gyroscopes in the storage library. It was not uncommon for him to do two things at the same time.

The book contains a lot of content, and it is very professional. Fortunately, Gao Zhendong's brain has been systematically strengthened, so although he cannot fully understand it in a short period of time, he can definitely get a general idea.

After trying two things at once for a while, Gao Zhendong found the problem.

These two comrades are indeed the professional and technical backbone of the original research institute. There is nothing wrong with the calculations. The reason for this result is that when they originally proposed the principle, the information source was a fragment of non-professional information sources such as Wikipedia. It is normal for non-professional information sources to have some problems. For example, this time, the problem is that interferometric measurement of optical path difference is the simplest method, but not the most accurate method.

These non-professional sources fully demonstrate the charm of journalism. When they talk about technology, they are talking about the simplest one, and when they talk about precision, they graft the highest precision of another technology.

It is a case of misidentification.

The Wiki misled me! Wiki is a rip-off!

It’s easy to solve once you find the problem. It’s not a problem to solve it.

Professional books have the advantage over crappy information sources!

Gao Zhendong withdrew his main thoughts from the storage and closed the other party's manuscript.

The two comrades knew that there was a conclusion, and they stared at him with inquiring eyes.

"Well, there is nothing wrong with your calculations. Interference cannot achieve that level of accuracy."

The optical interference method of measuring the optical path difference requires a relatively large optical loop to obtain a large enough optical path difference to make the optical interference fringes appear to move visibly. This is difficult to achieve in a practical gyroscope with limited size. This is also the reason why the Sagnac effect has been discovered long ago but has not been put into practical use in optical gyroscopes.

It wasn't until the advent of lasers that the situation improved somewhat due to its characteristics, but the accuracy still could not be improved to a very high level.

After hearing this, the two of them felt disappointed. It's not that it can't be used, but the huge difference in accuracy will undoubtedly greatly limit its scope of use.

But Gao Zhendong's next words brought them back to life.

"To achieve that level of precision, interferometry is not a problem. We need to use a different method, which is to oscillate the laser and measure the frequency difference between the forward and reverse oscillating lasers. This is also a way to measure the optical path difference."

When the two heard this, they suddenly remembered a sentence from Chief Engineer Gao in the initial principle materials given to them by the Defense Work Committee. The sentence said that interference measurement is only a method of measuring optical path difference, and they should not be bound by the method he gave as an example.

It is estimated that optical interferometry measurement was just something Chief Engineer Gao casually said at the time as the simplest and most easily understood method. This was to take into account the people who were listening to his explanation at the time. That comrade was probably not a professional in this field, so Chief Engineer Gao naturally chose the easiest to understand example.

As for professionals like us, what they say will definitely be more in-depth. Let's look at the latter method, which is much more professional. What is oscillating laser?
Thinking of this, they felt very ashamed and their faces turned red.

Chief Engineer Gao had reminded them of this matter in words and deeds a long time ago, but the two of them could only wait, rely on, and ask for things. They did their work comfortably within the circle given to them by others, and were at a loss when they left the circle drawn by others. They did not have any subjective initiative as scientific and technological workers, and in the end Chief Engineer Gao had to remind and explain it to them.

"Chief Engineer Gao, we didn't think this through. We are so ashamed. Can you explain to us what oscillating laser means?"

In front of the founder of lasers, they had nothing to be embarrassed about and started asking.

Well, you don’t have to feel ashamed. It’s true that I do feel a little sorry for you.

Gao Zhendong smiled with a little guilty conscience, "As for oscillating lasers, I will give you some materials later, and you will understand after you learn them. As for the advantage of this technology, it is that its output is a pulse signal. It is difficult for the sensor to observe the changes in interference fringes, but it is easy to count pulses."

Although the two people from the original research institute are not professional electronics experts, they still have some basic knowledge of the concepts. Counting pulses is so simple!

"I have done some theoretical calculations and used the Sagnac effect to measure the rotation angle and speed. The oscillating laser method is five orders of magnitude more accurate than interferometry under current technical conditions."

Why is it the current technical conditions? The main reason is that there is a technology that can produce miracles with great effort - fiber optic gyroscope, but the conditions are not available for the time being.

These words almost made the two people from the original research institute think that Gao Zhendong spoke incoherently or that they had heard it wrongly.

"Five orders of magnitude? Not five times?" The comrade from the original research institute confirmed with a shocked tone.

"Order of magnitude!" Gao Zhendong repeated very clearly.

There won't be any problem. Chief Engineer Gao can't joke about this kind of thing. The comrade from the original research institute had a gleam in his eyes: "Chief Engineer Gao, can you let us study your calculation manuscript? It's not that we don't trust you, but we have never been exposed to the theory in this area, and we really want to learn more."

Gao Zhendong nodded: "Well, after proposing this principle last time, I thought that I could carry out in-depth research, so I also took the time to do some related theoretical research. This time we will not discuss any specific technical implementations. I will show you my research first, and we can exchange ideas. After you have finished reading, we will talk about the rest, okay?"

(End of this chapter)