| Crappy LED trun signals [message #221602] |
Sa, 30 April 2005 02:07 |
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I saw a BMW today which has amber LED rear turn signals. They look
pretty good from the rear, but as the car turned in front of me, the off
axis intensity dropped off dramatically. When the car's axis was at
about 45 degrees with respect to me, the turn signals became almost
invisible.
I'm not sure of the legal requirements, but I'd like to be able to see a
car's turn signals even when I'm at right angles to it.
--
Paul Hovnanian mailto:Paul [at] Hovnanian.com
------------------------------------------------------------ ------
Drugs may be the road to nowhere, but at least they're the scenic route!
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| Re: Crappy LED trun signals [message #221608 ] |
Sa, 30 April 2005 03:54 |
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On Fri, 29 Apr 2005, Paul Hovnanian P.E. wrote:
> I saw a BMW today which has amber LED rear turn signals. They look
> pretty good from the rear, but as the car turned in front of me, the off
> axis intensity dropped off dramatically. When the car's axis was at
> about 45 degrees with respect to me, the turn signals became almost
> invisible. I'm not sure of the legal requirements, but I'd like to be
> able to see a car's turn signals even when I'm at right angles to it.
North American requirement: 45 degrees inboard to 45 degrees outboard.
Rest of world requirement: 45 degrees inboard to 80 degrees outboard.
Remember, America's right and the stupid rest of the world is wrong.
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| Re: Crappy LED trun signals [message #221614 ] |
Sa, 30 April 2005 05:27 |
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> North American requirement: 45 degrees inboard to 45 degrees outboard.
> Rest of world requirement: 45 degrees inboard to 80 degrees outboard.
>
> Remember, America's right and the stupid rest of the world is wrong.
And on the subject of LED taillights, can anyone else besides me see the
ridiculously low PWM frequency they use to drive the things? What is it,
about 70 hz? You turn your head quickly and you see a trail of blinking
LEDs.
Manufacturers, increase the the damn clock frequency, please!
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| Re: Crappy LED trun signals [message #221623 ] |
Sa, 30 April 2005 09:42 |
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> And on the subject of LED taillights, can anyone else besides me see the
> ridiculously low PWM frequency they use to drive the things? What is it,
> about 70 hz? You turn your head quickly and you see a trail of blinking
> LEDs.
I've seen this too... but it seems not to be universally true, almost
like some are pure DC...
Erik
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| Re: Crappy LED trun signals [message #221632 ] |
Sa, 30 April 2005 18:44 |
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On Fri, 29 Apr 2005, John Harlow wrote:
> And on the subject of LED taillights, can anyone else besides me see the
> ridiculously low PWM frequency they use to drive the things? What is
> it, about 70 hz? You turn your head quickly and you see a trail of
> blinking LEDs. Manufacturers, increase the the damn clock frequency,
> please!
Some LED taillamps are PWM'd to create the different intensity levels (dim
for tail, bright for brake). Others are resistively modulated, which means
no flicker effect when you scan across them with your eyes.
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| Re: Crappy LED trun signals [message #221748 ] |
Sa, 30 April 2005 03:54 |
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On Fri, 29 Apr 2005, Paul Hovnanian P.E. wrote:
> I saw a BMW today which has amber LED rear turn signals. They look
> pretty good from the rear, but as the car turned in front of me, the off
> axis intensity dropped off dramatically. When the car's axis was at
> about 45 degrees with respect to me, the turn signals became almost
> invisible. I'm not sure of the legal requirements, but I'd like to be
> able to see a car's turn signals even when I'm at right angles to it.
North American requirement: 45 degrees inboard to 45 degrees outboard.
Rest of world requirement: 45 degrees inboard to 80 degrees outboard.
Remember, America's right and the stupid rest of the world is wrong.
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| Re: Crappy LED trun signals [message #221761 ] |
Sa, 30 April 2005 05:27 |
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> North American requirement: 45 degrees inboard to 45 degrees outboard.
> Rest of world requirement: 45 degrees inboard to 80 degrees outboard.
>
> Remember, America's right and the stupid rest of the world is wrong.
And on the subject of LED taillights, can anyone else besides me see the
ridiculously low PWM frequency they use to drive the things? What is it,
about 70 hz? You turn your head quickly and you see a trail of blinking
LEDs.
Manufacturers, increase the the damn clock frequency, please!
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| Re: Crappy LED trun signals [message #221797 ] |
Sa, 30 April 2005 09:42 |
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> And on the subject of LED taillights, can anyone else besides me see the
> ridiculously low PWM frequency they use to drive the things? What is it,
> about 70 hz? You turn your head quickly and you see a trail of blinking
> LEDs.
I've seen this too... but it seems not to be universally true, almost
like some are pure DC...
Erik
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| Re: Crappy LED trun signals [message #221824 ] |
Sa, 30 April 2005 18:44 |
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On Fri, 29 Apr 2005, John Harlow wrote:
> And on the subject of LED taillights, can anyone else besides me see the
> ridiculously low PWM frequency they use to drive the things? What is
> it, about 70 hz? You turn your head quickly and you see a trail of
> blinking LEDs. Manufacturers, increase the the damn clock frequency,
> please!
Some LED taillamps are PWM'd to create the different intensity levels (dim
for tail, bright for brake). Others are resistively modulated, which means
no flicker effect when you scan across them with your eyes.
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| Re: Crappy LED trun signals [message #224609 ] |
Mo, 02 Mai 2005 16:26 |
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John Harlow wrote:
>>North American requirement: 45 degrees inboard to 45 degrees outboard.
>>Rest of world requirement: 45 degrees inboard to 80 degrees outboard.
>>
>>Remember, America's right and the stupid rest of the world is wrong.
>
>
> And on the subject of LED taillights, can anyone else besides me see the
> ridiculously low PWM frequency they use to drive the things? What is it,
> about 70 hz? You turn your head quickly and you see a trail of blinking
> LEDs.
>
> Manufacturers, increase the the damn clock frequency, please!
On some brands, not on others. The ones on Cadillacs, for instance,
don't cause me any problems. All GM's problems aside, the Cadillac
division is doing a whole lot of things right at the moment... apart
from styling anyway :-0
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| Re: Crappy LED trun signals [message #224705 ] |
Mo, 02 Mai 2005 16:26 |
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John Harlow wrote:
>>North American requirement: 45 degrees inboard to 45 degrees outboard.
>>Rest of world requirement: 45 degrees inboard to 80 degrees outboard.
>>
>>Remember, America's right and the stupid rest of the world is wrong.
>
>
> And on the subject of LED taillights, can anyone else besides me see the
> ridiculously low PWM frequency they use to drive the things? What is it,
> about 70 hz? You turn your head quickly and you see a trail of blinking
> LEDs.
>
> Manufacturers, increase the the damn clock frequency, please!
On some brands, not on others. The ones on Cadillacs, for instance,
don't cause me any problems. All GM's problems aside, the Cadillac
division is doing a whole lot of things right at the moment... apart
from styling anyway :-0
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