Optical fiber transmits signals through optical signals. In fact, there is a glass wire inside, which is not conductive. Therefore, no matter where it is pulled out, there is no voltage on the fiber, so you can use it with confidence.

However, the optical signal inside the optical fiber can damage the visual acuity, especially the optical fiber transmitted over a long distance. The optical signal has a wavelength of 1310 nm or 1550. This wavelength is beyond the visible range, so it is invisible, but it still depends on vision. Make an impact, so don't look at the core of the fiber.