“…Although the control of the writing time is a complicated process, the reduction of the inscription time is the development trend for the improvement of writing efficiency. Figure 2 shows the historical evolution of inscription time of POF Bragg gratings [44,46,52,64,65,68,70,81,85,86,91,92,95,99,102,106,112,115,120,121,126,127,132,140]. …”