GT taillights??

Necx0

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Just watching the 3 Supercars in France episode. I assume other people noticed the Ford GT's little trick with its taillights.

Anyone know how that works??? Looks very cool but rather a bizarre feature.....
 
Well, that's not what i'd call cool... :)

Apparently it's due to the LEDs which are used for the rear lights. Something to do with frequency or something.

But the best way to know is to go on the thread of the 7x03 episode where it has already been discused ;)
 
I assumed they were broken like ford's usually are :D
 
It has to do with the AC circuit in use in a car. As an LED is a diode it only permits current to flow in one direction. This causes the LED to flash at the same rate as the AC current, so if it were a 60HZ circuit, the LEDs would flash 60 times per second. Most people don't see them flashing, but there have been complaints from people who can (same with some people not noticing the difference between 60 and 72Hz refresh frequency on a monitor). When it's put on film the flashin means that for every frame the light intensity can vary and even that they're off in certain frames. Because the framerate of film is realatively low, the flashing becomes much more apparent.
 
Ah so if you are driving behind a Ford GT the human eye wouldn't notice it?? Or only some people??
 
It has to do with the AC circuit in use in a car. As an LED is a diode it only permits current to flow in one direction. This causes the LED to flash at the same rate as the AC current, so if it were a 60HZ circuit, the LEDs would flash 60 times per second. Most people don't see them flashing, but there have been complaints from people who can (same with some people not noticing the difference between 60 and 72Hz refresh frequency on a monitor). When it's put on film the flashin means that for every frame the light intensity can vary and even that they're off in certain frames. Because the framerate of film is realatively low, the flashing becomes much more apparent.

yeah ive noticed this on some buses around here, their led stop and indicators give you the sense that they are flickering very slightly

i got some LED tail lights for my car, but since they plug into regular sockets im assuming they are DC and hence dont flicker.

why would a car use AC? battery is DC of course, electronics use DC and id imagine that due to its name the alternator produces AC, but why would they use the AC for the lights?

im not saying your wrong, i think you hit the nail on the head, im just trying to understand.
 
It has to do with the AC circuit in use in a car. As an LED is a diode it only permits current to flow in one direction. This causes the LED to flash at the same rate as the AC current, so if it were a 60HZ circuit, the LEDs would flash 60 times per second. Most people don't see them flashing, but there have been complaints from people who can (same with some people not noticing the difference between 60 and 72Hz refresh frequency on a monitor). When it's put on film the flashin means that for every frame the light intensity can vary and even that they're off in certain frames. Because the framerate of film is realatively low, the flashing becomes much more apparent.

Does this phenomenon also explain why CRT monitors appear flickery when filmed on a bog standard home video camera?
 
Ah You're all a clever bunch!!! Thanks for that!
 
Not all LED's do it, either. You can make an LED very bright two ways: one is to make an LED shine brightly, all the time. The other, much cheaper way, is to make a lower-quality LED that can be bright in very very short flashes. If the current was flowing through the LED at a constant flow, the LED wouldn't be able to shine as brightly, unless it was a higher-quality, much more expensive LED.
 
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