Speed of eye response to red vs green LEDs

[james_s]

At turning on? Why? And by how much?

Surely not enough to be visible. It may take some finite amount of time for the phosphor to respond and start emitting light but that's going to be a very *very* small amount of time in human terms.

[hamster_nz]

You would think nobody here had a few spare LEDs, a micro controller, an couple of LDRs or photodiodes and a dual-channel scope.... 

I might do some tests tonight and post results.

[iMo]

https://en.wikipedia.org/wiki/Rhodopsin
https://en.wikipedia.org/wiki/Visual_phototransduction
The LEDs are pretty strong source of light today. It could be the above processes apply in a much stronger way when starring into the red/green/blue LEDs thus there are delays in the processing the colors.

[onesixright]

 
Apart from being an attention test, that is also a good proof that we don't perceive what the reality is, but what the mind expect it to be. We are not aware about this, but what we perceive is a continuous fabricated daydream guided by reality, instead of perceiving the reality.

Yeah, and thats says what about eye-witnesses ?

[GreyWoolfe]

Yeah, and thats says what about eye-witnesses ?

What are you doing even leaving eyewitnesses?

[StillTrying]

Added a few 5mm LEDs.
www.eevblog.com/forum/chat/20w-halogen-bulb-viewed-by-a-photodiode/msg1751210/#msg1751210

[hamster_nz]

Added a few 5mm LEDs.
www.eevblog.com/forum/chat/20w-halogen-bulb-viewed-by-a-photodiode/msg1751210/#msg1751210

Excellent results! At least for your LEDs we are talking a fraction of a ms. I did some inconclusive testing with a LDR last night.... the LDR was too slow to be of any use.

[IconicPCB]

The eye gets fooled by frame rates greater than 18Hz.
That would be a good starting point