Tunnels, as a kind of road, whether in bright daytime or dark night, no matter what weather, should give drivers and pedestrians with security and comfort. For the practical needs of
LED tunnel flood lights design, long tunnel is generally divided into 3 sections, each section has corresponding visual problems.
- Approaching paragraph: A section of road near the entrance to the tunnel in which the driver must see the object inside the tunnel. This stage of the road driver’s self vision adjustment also determines the brightness requirements for tunnel openings and tunnel entry sections. During the day, due to the high brightness of the inlet environment and the strong contrast of the low brightness in the tunnel, also due to the driver’s eyes on the visual retention of the bright environment, a less-than-enough tunnel mouth will cause a “black hole effect” can not see any detail in the hole; and at night, as the driver’s eyes adapted to the darkness outside the tunnel, The same tunnel may feel good illumination.
2. Entry section: It is the first paragraph in the 4 sections of the tunnel and must be made to see the road surface of the entrance section before the driver entering the section. The length of the entry section depends on the maximum Grosvenor speed of the tunnel design and is equal to the safe braking distance (SSD) at the highest speed. This is because, at the farthest surface of this section, the driver who is ready to enter the entrance to the tunnel outside the safe braking distance can see the obstacle.
3. Export section: The last section of one-way tunnel, because the driver’s vision will be affected by the brightness of natural roadway tunnel lighting outside the tunnel, it may cause the driver not to find the car in the shadow of the big truck in time, so we should pay more attention to the design of the light.