LED lights

[ghetdjc320]

They are everywhere now it seems. But I’m starting to notice the intense pulse or strobing effect they all have. Seems like the cheaper ones are even worse. I most all led lights strobe at very high frequencies. Anyone else noticing the effect? Feels like it’s causing eye strain. Noticing a lot of aftermarket auto lighting seems to be making it worse unless it’s higher quality

[derf]

Yeah, the lights use LEDs that are probably too bright if left at constant 12-14V.  You really can't step down the voltage to an LED like you can with an incandescent bulb.  So they use pulse modulation (turning on and off the power relatively fast) to reduce the brightness.

 

But the cheap components do tend to flicker more than they would with better quality parts.  Adjusting the pulse rate would probably do wonders but it's probably more expensive to have the controller that doesn't make the light flicker so badly.

 

 

Part of it may be that the controller adjusts the flicker rate to match the incoming voltage.  And with old cars, you're not getting full voltage to the lights (old wires, corroded contacts in the plug and the switch, etc).  So the lights flicker badly.

[ghetdjc320]

3 hours ago, derf said:

Yeah, the lights use LEDs that are probably too bright if left at constant 12-14V.  You really can't step down the voltage to an LED like you can with an incandescent bulb.  So they use pulse modulation (turning on and off the power relatively fast) to reduce the brightness.

 

But the cheap components do tend to flicker more than they would with better quality parts.  Adjusting the pulse rate would probably do wonders but it's probably more expensive to have the controller that doesn't make the light flicker so badly.

 

 

Part of it may be that the controller adjusts the flicker rate to match the incoming voltage.  And with old cars, you're not getting full voltage to the lights (old wires, corroded contacts in the plug and the switch, etc).  So the lights flicker badly.

That makes sense. I hadn’t considered how PWM was used to control led brightness. Somehow, I feel there may be some lasting effects on our vision with the proliferation of LED tech everywhere, but especially the lower quality stuff like you mentioned. 

[White_Comanche]

Everyday flashlights and worklights are dangerous to look at now, even briefly, in my opinion. High lumen LED products are common to find these days. I’m surprised we don’t see reports of kids having accidental eye injury.

 

Also, headlights on modern trucks and SUVs are almost blinding at night.

[eaglescout526]

6 minutes ago, White_Comanche said:

Also, headlights on modern trucks and SUVs are almost blinding at night.

My exact thought when I saw this thread. 
 

And most people don’t know they’re blinding you and don’t really care either. You signal your highbeams to let them know your being blinded and they end up cranking up the blindness to 11 with their atomic highbeams. 

[pizzaman09]

The only time I can think of noticing LEDs flicker was when I was in an old Italian hotel.  The mirror in the bathroom had LED lights around it that flickered at the mains frequency, it was terrible.  

 

The LEDs I used for the headlights of my Austin Healey Sprite will flicker some, but it's voltage related as the old generator and voltage regulator aren't as consistent at putting out a clean voltage as a modern alternator.

[Spinnakerblue89]

I've not yet seen a pair of LED headlights I would trust long term, or any other LED lights for that matter. Every LED I've ever had unless it's like a small replacement one I've had to solder into a circuit board, has petered out quicker than incandescents and halogens for me. 

 

Locally, I think they have become a bit of a menace. A lot of good ol' boys in their lifted Chevys and Dodges like to blind people with improperly adjusted lights.