N-BK7 Ball Lenses are glass spheres commonly used in fiber optic applications, ball lenses are ideal for focusing light into optical fibers, or for fiber coupling. Fused Silica features high transmission from 200nm to 2.2μm with a low coefficient of thermal expansion, making it ideal for the most demanding ball lens applications in the ultraviolet, visible, and near infrared spectra.
Ball lenses are commonly used for improving signal coupling between fibers, emitters, and detectors, as well as objective lenses in endoscopy and bar-code scanning applications. Half-ball lenses simplify handling and integration.
Ball Lens Half-Ball Lens
Specification of our ball lens: Schott Bk7 Ball Lens,Bk7 Ball Lenses,Schott N-Bk7 Glass Ball Lens,Schott Bk7 Half Ball Lens China Star Optics Technology Co.,Ltd. , https://www.opticsrealpoo.com
The famous Kimberley big hole diamonds in South Africa were first sent to the ground by volcanic eruptions, and most of them were located in a rock tube or “throat†called kimberlite, which passed through the crust to the ground like a pipe in the ground. on. Since these rock pipes are formed by ancient volcanic movements, the excavators only have to dig down as much as possible to dig diamonds until the hills become a hole. Today, it is simply called The Big Hole. Today, the Kimberley Cave is a famous tourist destination. It covers an area of ​​17 hectares and has a radius of 1.6 kilometers. About 22 million tons of soil were dug away from it, producing 14,504,566 carats of diamonds (about 2,722 kilograms) until 1914, when the stones were completely dug. At the time, the open pit mine was 215 meters deep and the mining tunnel was as deep as 1,100 meters. At present, water seepage and rain have flooded half of the hole. Geologists have also discovered other diamond-bearing kimberlite mines in South Africa, and today there are many large holes around Kimberley and other parts of South Africa. South Africa is a big country in today's world of diamond production. How is the diamond made in the ground? Diamonds are derived from carbon particles in the mantle. Due to the combination of high temperature and high pressure, carbon is crystallized and turned into diamonds. Most of the diamonds are found in kimberlite tubes like rock pillars, which are shaped like oval cylinders or funnels that are large and small. When the rock pillar is eroded by external forces, it forms an impact diamond sand mine or a coastal sand mine. Diamonds such as India and Brazil are produced in such an alluvial stratum. For diamond-bearing kimberlites, most are located on ancient platforms or shields. As a result, most diamonds have a history of more than 3 billion years, even though the youngest diamonds were formed 70 million years ago. Although it does not show a long and ancient evolutionary history like a creature, it also has an imprint of the times. The melting point of the diamond is 1878 ° C, which is 2.5 times that of steel. The yellow color of many diamonds is created by residual nitrogen, which is also greatly reduced in quality evaluation. However, today's market is also a fashionable accessory. In pure or white diamonds, nitrogen has not been traced after millions of years of filtration. Although diamonds are the hardest substance in nature, they can be broken with a hammer and burned at a certain high temperature. How do Africans “wash†and “grind†diamonds? In Africa, as long as the villages or small towns close to the diamond producing areas are eating diamonds, because the quality of the diamonds is high and the price is high, the jewelers who can really get involved in the diamond trade are still quite rich. However, the miners and migrant workers who have worked hard to clean the diamonds from the mud sands, they not only sell the lowest price, but also get a high-priced diamond is not easy, so their lives will not necessarily be there. How rich, and at the same time, this high-intensity labor also makes them unfortunately ill, and the family is broken. These are somewhat similar to miners in other industries, such as gold mines and coal mines. Although the return on ore is quite high, the profit-seekers are not the people who work, but their bosses. Let's walk into the seemingly rich people, but in fact the majority of the poor African land, to understand the hard work of diamond workers looking for diamonds. 
In the morning sunrise, the diamond mining area is still very quiet. For those who are far away from the diamond mine, looking for diamonds, they will get some smaller particles of diamonds along the ore-differentiated river basin. 
The sun is rising, more and more people are mining 
Only the fish can see the scene abound in the diamond mining area in Africa. 
In addition to washing, you have to use your hands to figure out 
The same work, different opportunities may have very different results 
Will there be a miracle in these remaining sandstones? 
No effort, flush out a yellow inferior diamond 
This is a life-saving stone. It will be a good day to find it. Every diamond carries the hard work and sweat of African miners. 
These people, who are regarded by the people as bosses, come to buy unfinished rough diamonds. 
The identified diamonds are also classified according to the color
*Material:BK7 or other optical glasses,optical crystal materials
*Diameter:1mm - 40mm
*Dimension Tolerance:+/-0.005mm
*Surface Quality:40-20
*Sphericity:0.005mm
*Coating:optional
Telling - South Africa's diamond story
How do South Africa have diamonds? The story of South African diamonds can be traced back to 1870, when a farmer named Adriann van Wyk owned a farm near Kimberley in the Northern Cape when he found his children. When you are playing with a few diamonds, everything starts here. Why are there so many diamonds in South Africa? It turned out that volcanic activity occurred in the geological history of South Africa. The intense high temperature crystallized this component of carbon into diamond. The high-quality diamond became the first choice for people's ornaments, and it was gradually called diamond.