Analysis of existing programs _led LED dimming dis

wee960t2e · Wysłany: Pon 3:31, 21 Mar 2011

During the day,[link widoczny dla zalogowanych], the tunnel exit section of the lighting levels with the entrance of the lighting levels,[link widoczny dla zalogowanych], basic lighting inside the tunnel should be higher than the value of high brightness; at night, on the contrary, basic lighting inside the tunnel should be lower than the brightness value, when the tunnel outside the street lighting, the value of the tunnel road surface brightness value of not less than 2 times the brightness of the open.
econd, the vehicle through the tunnel problems in the process of 1. Closer tunnel problems in the process of the phenomenon of black holes during the day, the eyes have adapted to outdoor motor vehicle drivers up to more than 10 million lx cd/m2 of thousands of natural light, when the eyes to light only a few cd/m2 tunnel environment,[link widoczny dla zalogowanych], the difference of brightness the human eye perception is limited, appear to adapt to lag, you will see a black cave, while the state does not recognize them.
Like to see in bright environments the phenomenon of black holes is called the black hole phenomenon. Once the black hole phenomenon, with the vehicle close to the tunnel, shortening the distance the driver's visibility and can not drive safely. The black hole phenomenon is occurring before entering the tunnel vision problem is the tunnel lighting, the most important issue.
To prevent the occurrence of the black hole phenomenon, starting from the tunnel entrance in a distance sufficient intensity to ensure that this part of the length of braking distance than the safety of motor vehicles slightly longer. Entering the tunnel,[link widoczny dla zalogowanych], because there is a big inside and outside the brightness difference, adaptation of the delay, the driver can not adapt quickly channel the visual brightness, it is difficult to see the interior of the tunnel.
To prevent this from happening, should enable the tunnel entrance brightness decreased slowly with the degree of visual adaptation and brightness to a smooth transition should be gradual to reduce the brightness, but before and after the brightness level brightness level is worth more than 3:1 ratio, and 2m high Following the brightness of the wall surface can not be lower than the average brightness.