At what frequency does the human eye notice flicker?

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> At what frequency does the human eye notice flicker?

those of us trained in detecting PWM can spot it below 1000 mhz
but an oscillator can tell with even higher values

> Okay so power management in LED’s is achieved by turning the led on and off so fast the human eye doesnt notice it

I do not think that is a correct definition of power management. It IS a definition of using PWM to dim a light

> the total “on time” is essentially reduced by 50%

yes, if you are using 50% PWM, but there are other variations. There are also pulses that do not drop all the way to Zero, hence not true PWM, but still pulsed. Zebralight is an example of a maker that uses pulses that do not drop to zero and most users cannot detect it by waving the light, or by photograph, but they still show on an oscilloscope

> therefore doubling the amount of time the LED can produce photons?

I do not follow that logic. If the LED is off half the time, it produces photons Half the time, not double.

dehc111 wrote:
My idea is not flawed. Perhaps not defined correctly and my vernacular in error but the concept has merit .

I dont think I undertand your what your idea IS.

dehc111 wrote:
I completely understand why everyone thinks I am wrong… Why put multiple LED’s in a light when you can achieve the same thing from a single LED of higher power?

The comments are that your assumptions are not supported by fact. If you ask the wrong question, you get the wrong answer. Let me give you an example of a question that may not be valid:
“Do you still beat your wife?”
explanation, the assumption in the question is that you DID at one time beat your wife. This is (hopefully) flawed.

Similarly, your assumption in this thread is that LED power management REQUIRES PWM. I dont think that is accurate. I for one will NOT buy a light that uses PWM. I wont even buy a light that uses Pulses that dont drop to zero. Even if I cant see them, I do not choose to own lights that strobe my brain, even if I cannot consciously “see” the pulses.

To the best of my ability, I think your question is something like this.
Assume light with 4 LEDs. You want to Pulse them On and OFF at 50% on time, and you want the pulses to each light not be simultaneous. Sure, you CAN do that, but WHY?

Pulsing will NEVER produce as MUCH light as leaving the LED ON constantly.

PWM is a DIMMING strategy, designed to preserve the Tint of the output. PWM is NOT used on Maximum brightness modes.

I hope you take no offense at my attempt to point out what appears to be a contradiction of terms and assumptions.

Yes you can pulse leds independently, but WHY?

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