A gift from God

Motivated by a fighting spirit, we set out with our backs against the wall in a completely competitive arena, and the name Fujikura suddenly resounded throughout the world.

In addition to the sense of social mission, Fujikura also felt a sense of crisis that "we have no future if we don't gain an advantage in the development of Optcal Fiber!", and so began the research and development with a desperate attitude. The joint research with Nippon Telegraph and Telephone Public Corporation was essentially a completely competitive forum, with research results announced once a month and the winner decided each time. The first research theme was "approach to ultra-low loss." Once the joint research began, the targets kept increasing, and there was no time to slack off. The researchers were so absorbed in their experiments that they forgot to eat and sleep. Using Bell Labs' most advanced method at the time (MCVD method = internal chemical vapor deposition method), Fujikura repeated hypothesis and verification, and soon completed a fiber with a loss of 1.5 dB/km at a wavelength of 0.85 μm. The analysis results of this fiber showed a aspect that was different from previous fibers.

According to a graph showing the relationship between wavelength and loss in silica glass Optcal Fiber at that time, there was a large peak of loss due to moisture (hydroxyl groups) in Optcal Fiber at around 0.95 μm wavelength. However, the fiber made by Fujikura had extremely little loss due to moisture. This is because Fujikura's researchers thoroughly pursued and succeeded in developing technology to remove water during manufacturing process. The Nippon Telegraph and Telephone Public Corporation's Ibaraki Communication Research Laboratory, realizing the importance of Fujikura's optical Optcal Fiber, used a precision measuring device that had been developed for the long wavelength band of 1.1 to 3 μm to measure in the longer wavelength range. As a result, in March 1976, they discovered a minimum loss point of 0.47 dB/km at a wavelength of 1.2 μm, approaching the theoretical limit.

This groundbreaking result was submitted to the British Institute of Electrical Engineers' journal, "Electronics Letters," in collaboration with the Ibaraki Communication Laboratory. The paper, titled "Wavelength loss characteristics of Optcal Fiber with low hydroxyl groups," published in the June 10, 1976 issue of the journal, became "one of the most cited papers in the world" in the field of optical communications, and received honors such as the British IEE's Best Paper of the Year Award, as well as the Japan Institute of Electrical Communication Engineers' Achievement Award (1976) and the Science and Technology Agency's Research Achievement Award (1978). This made Fujikura's name known around the world, and the company went on to be a leader in low-loss fibers.

Paper published in Electronics Letters