How Did People Invent Optical Fiber?

One day in 1870, The British physicist Tyndall came to the Lecture hall of the Royal Society in Britain to speak about the principle of total reflection of light. He did a simple experiment: he drilled a hole in a bucket filled with water and used a lamp to remove it from the top of the bucket. The water is bright. The results surprised the audience. The glint of water was seen flowing out of the hole in the bucket, and the water bent and the light bent, and the light was caught by the tortuous water.

Light energy was found to travel along the stream of wine from the barrel; Light energy was also found to travel along the curved glass rod. Why is that? Isn't the light straight? These phenomena caught Tyndall's attention. After his research, he found that it was the total reflection effect of light [2]. Since the density of water and other media is greater than that of the surrounding material (such as air), light is transmitted from water to air. When the incident Angle is greater than a certain Angle, the refracted light disappears and all light is reflected back into the water. On the surface, light appears to bend forward in the flow of water.

Later, people created a kind of glass fiber with the transparency and thickness of spider silk. When light enters the glass fiber at the right Angle, it travels along the curved glass fiber. Because this kind of optical fiber can be used to transmit light, it is called optical fiber.