Neodymium glass? This is a kind of glass containing rare earth ion neodymium, which looks like a piece of purple glass.
As for the role, it refers to the application in the laser field.
Today, let's talk about laser and neodymium glass.
Development history of laser in China
The word "laser" is a free translation of a word composed of 48 letters.
It is estimated that some people will be wrong when talking about this. The English of laser is LASER, which is actually the original combination of a long string of words, simplified.
I have to say that the charm of Chinese, any new thing, can use the words created by the old ancestors to combine its name, and you can roughly know what it means at a glance.
However, when the word was first introduced into China, it was also translated in a variety of ways, mainly because there was no unified standard, and some were transliterated according to the meaning of the word itself.
For example, it is called Lesser, laser, light stimulated radiation amplifier and so on. This phenomenon cannot last forever. After all, it is the content of the scientific field. So in 1964, Qian Xuesen fixed its name, that is, laser.
This is the origin of the word laser.
In fact, the principle of laser has been discovered as early as 1916, and its brightness is 10 billion times that of sunlight. But it was really made in 1960.
Relatively speaking, the research on laser in China is not late. As early as 1957, the Institute of Optics and Fine Mechanics was established. Its full name is the Institute of Optics, Precision Instruments and Machinery of the Chinese Academy of Sciences.
At that time, Chinese scientific research was all about bringing the old with the new. A group of young people grew up rapidly under the cultivation of the older generation.
China has many professionals in the laser field.
To put it simply, the world's first laser was born in 1960, while China successfully developed its first laser in 1961.
However, the first laser developed in China has very low efficiency and energy.
But anyway, this laser has given China a foundation from scratch.
Later, many achievements were made.
For example, in 1964, we used lasers to transmit TV images, and even used lasers to make calls within 30 kilometers.
In 1965, the laser retinal welder was also used for animal clinical trials.
Since then, laser application equipment has been developed in all walks of life.
Today, China's deep cultivation in the laser field is not only the world's first, but also a member of the world's first echelon.
Such achievements are the foundation laid at the moment when the optical machinery was founded.
Let's take a look at China's laser development field.
The most eye-catching laser is the military laser. In 1966, China began research in this field.
The first is the laser ranging, which can measure the distance of 660 kilometers with an accuracy of less than two meters.
The equipment developed has finally become a key equipment on intercontinental missiles.
If such equipment is placed on a satellite, it will have a longer distance (2300 kilometers).
Although it is a simple distance measurement, it is widely used in military affairs, such as tracking distance measurement between aircraft, missile to aircraft distance measurement, ground to aircraft distance measurement, etc.
Once you say these names, you can realize the power of laser ranging.
This is just the unexpected effect of laser ranging, let alone other laser characteristics.
For example, the application of high power laser in nuclear fusion has two ways to produce nuclear fusion, one of which is to ignite nuclear fusion with high power laser.
In fact, with the development of laser, there are many branches, such as the laser related to neodymium glass.
At first, the combination of these two things was called high-energy neodymium glass laser system.
China started the project as early as 1964. However, due to the heat effect, the combination of the two became difficult, so the project was dismissed in 1976.
At that time, a large oscillating laser system with a diameter of 120 mm was built, and the output energy could reach 320000 joules.
The achievements are also quite outstanding.
Although he was dismounted, the technical reserve was kept, and talents in related fields were cultivated.
Neodymium glass
Neodymium glass is a special glass made of rare earth neodymium ions.
So what does it do?
Neodymium glass is known as the heart of laser. It can produce laser under certain conditions, even amplify the laser.
For example, in a device equipped with thousands of laser neodymium glasses, put a tiny negligible laser, and finally pass through these laser neodymium glasses, the laser energy level can be compared with the sun.
As mentioned above, the high-energy Nd glass laser system has been dismounted, but the related research has not stopped.
The development of neodymium glass has been studied for three generations.
As early as 1964, when Shanghai Institute of Optics and Fine Mechanics was founded, neodymium glass had been included in the task list for research and development.
The first generation neodymium glass is silicate neodymium glass used in high-energy laser systems.
The second generation neodymium glass is a functional phosphate neodymium glass used in high-energy laser systems.
The third generation is the development of N31 phosphate laser neodymium glass.
Although the research on neodymium glass in China started very early, it is backward in the relevant crucible smelting technology, which was blocked by foreign countries before 2005.
Crucible smelting technology is developed from crucible smelting, then semi continuous smelting, and then continuous smelting.
In the end, China broke through this technical difficulty, and a scientist named Hu Lili played an important role in it.
In 2001, she began to study neodymium glass.
It must be noted here that Hu Lili's previous research topic was glass, but this change can be said to make her start over again.
Speaking of this, many people do not understand that is not neodymium glass glass?
From the perspective of scientific research, it can't be regarded as true. There are fundamental differences between the two.
Therefore, when Hu Lili accepted the research on neodymium glass, the outside world did not think highly of her research based on her work experience.
Don't do it if you don't like it?
It's impossible. Opportunities are always reserved for those who are prepared. In order to break through difficulties, Hu Lili combed over and over again from theory to technology research and development, and even process flow.
Finally, she found the shortcomings of the previous crucible smelting technology, so by 2005, Hu Lili had a heavy burden on her shoulders, breaking the monopoly of foreign laser Nd glass continuous smelting technology.
According to the words at that time, this was a challenge to the limits of optical glass.
At that time, only two companies mastered this technology, one was Livermore National Laboratory in the United States and the optical glass company in Germany, the other was the optical glass company in Japan.
No third institution has mastered this technology.
Even the continuous melting technology of neodymium glass has been listed by the United States as the first of the seven wonders of the national ignition device.
Therefore, not only technology, but also related products of laser neodymium glass are banned from China.
From these descriptions, we can see the importance of the crucible continuous melting technology of neodymium glass.
In the face of technical blockade, everything has to be innovated, and innovation is still under self exploration.
At that time, Hu Lili's team did everything possible to absorb relevant knowledge, books, and first-line glass smelting workers' experience.
Difficulties are hard to break, don't they have to?
After absorbing enough knowledge and preparing enough, the experiment began.
The experimental site is very simple, that is, a 500 square meter shed, which is a common shed built with color steel plates on the construction site.
This kind of work shed does not avoid summer heat and is not cold resistant in winter.
Of course, it doesn't matter when the environment arrives. The most troublesome thing is the difficulties encountered during the experiment.
For example, when annealing, there was always the problem of cracking. At that time, foreign aid experts were invited. As a result, the experts came to the scene, looked at it and concluded that it could not be solved.
Can't we solve it?
If the neodymium glass does not break through one day, it means that someone else gets stuck in the neck for one more day.
Foreign aid experts are not good. They can only find problems by themselves.
Then, from the characteristics of neodymium glass to the structure of tunnel kiln, the problems were broken down into small problems for research.
Finally, the tunnel kiln burning neodymium glass was dug up and rebuilt according to the plan.
Every question is verified again. This small question has been verified more than 50 times before and after.
After ten years of dismantling problems, studying small problems and solving big problems, laser neodymium glass products finally appeared in front of us.
In 2012, China created the first continuous melting production line of laser neodymium glass, which can produce 1200 pieces of large-size phosphate laser neodymium glass a year, with technology improved three times and efficiency improved ten times.
It is expected that only 250 mm diameter neodymium glass can be produced, but 400 mm diameter neodymium glass can actually be produced.
While obtaining nine invention patents, this technology has also formulated three industry standards to meet the needs of the country.
Prohibition of neodymium glass export
In 2022, the state decided to add the neodymium glass manufacturing industry to the list of prohibited exports for the sake of safety.
Moreover, export restrictions have been set on some rare earths.
This decision will inevitably lead to an increase in the price of neodymium glass.
After all, scarcity is the most important thing. China's ban on exports means that the scarcity of related products and raw materials directly leads to the growth of production costs.
Even if you have money, you may not be able to buy it.
Then in February 2023, the Ministry of Commerce of China issued a catalogue of technologies prohibited from export and restricted from export, which includes 139 technologies.
It still includes the production process of neodymium glass, especially the large-sized neodymium glass.
So the impact will continue.
What do you think of the ban on the export of neodymium glass related technical products?
