LuisM
Registered User
Yep. They do. Here's a proof.
This is a picture of the A3 8V daytime LED lights, taken at 1/50 s shutter speed, without image stabilization. The catch is, the camera was moving vertically. You see five instances of the daytime light strip, which indicates that LED turns on and off about 50*5 = 250 times per second, or 250 Hz.
By the way, the yellowish fog lights below show the LED lights a continuous vertical displacement in the picture, instead of several distinct positions. They are standard lamps, not LEDS. So no flicker.
Some people notice this flickering with their naked eyes. Most seem not to. I'm among the "lucky" ones who notice it. If that's not your case, don't be sad. It's not particularly nice to see lights flickering all over the place.
Yes, all over the place. Because it's not only head lights. The car's interior lights, speedometer, even the circular lights of the glass containers below the climate controls: they all flicker. The following two pictures illustrate this. They were taken with 1/25 shutter speed. If you count the number of instances of each light or mark in the speedometer, you can see
Tail light LED lights, on the contary, don't flicker in the A3 8V. (They do flicker in other cars. Main offender for me is the Peugeot 307 cc. Their tail lights are really annoying. I hate to drive behind one of those at night.) As the picture below shows, the tail lights produce a continuous band when the camera is moved vertically. Shutter speed is 1/100 s, so even frequencies as high as 1000 Hz should have been detected (the tail light would have been seen at 10 distinct positions). By the way, the dimmer light in the lower right corner is just a reflection.
Do you perceive this flickering in LED lights? Do you find it annoying? It is for me, and for other people too. But I guess it's not many of us who do notice it, otherwise there would be more complaints, and car makers would rise flicker frequency so it wouldn't be annoying anymore. In my case, for example, 600 Hz (as in the DIS) is already unnoticeable.
This is a picture of the A3 8V daytime LED lights, taken at 1/50 s shutter speed, without image stabilization. The catch is, the camera was moving vertically. You see five instances of the daytime light strip, which indicates that LED turns on and off about 50*5 = 250 times per second, or 250 Hz.
By the way, the yellowish fog lights below show the LED lights a continuous vertical displacement in the picture, instead of several distinct positions. They are standard lamps, not LEDS. So no flicker.
Some people notice this flickering with their naked eyes. Most seem not to. I'm among the "lucky" ones who notice it. If that's not your case, don't be sad. It's not particularly nice to see lights flickering all over the place.
Yes, all over the place. Because it's not only head lights. The car's interior lights, speedometer, even the circular lights of the glass containers below the climate controls: they all flicker. The following two pictures illustrate this. They were taken with 1/25 shutter speed. If you count the number of instances of each light or mark in the speedometer, you can see
- 8 instances for the circular lights under the climate control buttons. This number applies also for upper lights, and for the button that turns on the emergency lights (all-blinkers); although they are not shown in this picture. So their flicker frequency is 200 Hz.
- Speedometer, RPM-meter: 10 instances. So they flicker at 250 Hz. Note, however, that whereas numbers and outer marks do flicker, indicator lights for EPC or safety belt don't: they leave a continuous trace.
- The DIS flickers faster. The horizontal line right under the car plot appears 24 times in the picture. So 24*25 = 600 Hz. This was a surprise for me, as I don't notice the DIS flickering with the naked eye. So now I know that the threshold above which I don't perceive the flickering is between 250 Hz and 600 Hz.
Tail light LED lights, on the contary, don't flicker in the A3 8V. (They do flicker in other cars. Main offender for me is the Peugeot 307 cc. Their tail lights are really annoying. I hate to drive behind one of those at night.) As the picture below shows, the tail lights produce a continuous band when the camera is moved vertically. Shutter speed is 1/100 s, so even frequencies as high as 1000 Hz should have been detected (the tail light would have been seen at 10 distinct positions). By the way, the dimmer light in the lower right corner is just a reflection.
Do you perceive this flickering in LED lights? Do you find it annoying? It is for me, and for other people too. But I guess it's not many of us who do notice it, otherwise there would be more complaints, and car makers would rise flicker frequency so it wouldn't be annoying anymore. In my case, for example, 600 Hz (as in the DIS) is already unnoticeable.
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