Optical Fiber Development History

One day in 1870, the British physicist Tyndall went to the lecture hall of the Royal Society to talk about the principle of total reflection of light. He made a simple experiment: drill a hole in a wooden barrel filled with water, and then use a lamp to put the light from the top of the barrel. Water illuminates. The results surprised the audience. It was seen that the luminous water flowed out of the small hole in the bucket, the water was bent, and the light was bent, and the light was actually captured by the bent water.

It has been found that light travels along a fine stream of wine that is ejected from a barrel; it has also been found that light travels along a curved glass rod. Why is this? Is the light no longer going straight in? These phenomena caught Tyndall's attention. After his research, he found that it is the effect of total reflection of light [2]. Since the density of medium such as water is greater than that of surrounding matter (such as air), that is, light is shot from water to air, When the incident angle is greater than a certain angle, the refracted light disappears and all the light is reflected back into the water. On the surface, the light appears to be bending forward in the current.

Later, people created a kind of glass fiber with high transparency and thickness like spider silk-glass fiber. When light enters the glass fiber at a suitable angle, the light travels along the curved glass fiber. Since this fiber can be used to transmit light, it is called an optical fiber.