Plastic optical fiber achieves higher transmission speed
The research of plastic optical fiber began in the 1960s. In 1968, DuPont of the United States used polymethyl methacrylate as the core material to prepare plastic optical fibers, but the optical loss was relatively large. In 1974, Japan's Mitsubishi Rayon Company developed a plastic optical fiber with PMMA and polystyrene as the core material and low refractive index fluoroplastic as the cladding. Its optical loss was 3500dB/km, which was difficult to use for communication.
In the 1980s, some large companies and universities in Japan conducted a lot of research on the preparation of low-loss plastic optical fibers. In 1980, Mitsubishi Corporation polymerized PMMA with high-purity MMA monomer to reduce the loss of plastic optical fiber to 100-200dB/km. In 1983, NTT began to replace the H atoms in PMMA with deuterium, so that the lowest light loss can reach 20dB/km, and it can transmit light waves from near infrared to visible light.
In recent years, companies in Europe, Japan and other countries have made important progress in the development of plastic optical fibers. The optical loss rate of the plastic optical fiber developed by them has dropped to 25-9 decibels/km. Its working wavelength has been extended to 870 microns (near infrared light), which is close to the practical level of silica glass fiber. A PFX plastic series optical fiber developed by the United States has excellent radiation resistance. In addition, the Opti-Giga plastic optical fiber developed by the Boston Optical Fiber Company in Massachusetts is more eye-catching. It is not only lighter, more flexible and lower cost than glass, but also can transmit data at a speed of 3 megabits per second within 100 meters. . This kind of fiber can also use the refraction of light or the jumping mode of light in the fiber to achieve higher transmission speed. Now the United States, Europe and Japan have used plastic optical fibers for short-distance transmission, such as automobiles, medical equipment, and copiers.
