RGB LED exhibits a sparkle"-effect. Looks like a ray or sunburst pattern floating a couple cm out from device?

Thread Starter

Hamlet

Joined Jun 10, 2015
450
I don't know if my eyes are getting really bad, or what the heck I am seeing. Either with my glasses on, or off,
when looking at a RED-GREEN-BLUE led, I see a starburst effect, that looks sort of like a dandelion seed head, brightly illuminated.

Is this indeed what I am seeing, or do I need to get my eyes checked? I see it with either eye. I've had lasik surgery in the past, so maybe it's a side effect. If what I am seeing is normal, how is it achieved?
 

Thread Starter

Hamlet

Joined Jun 10, 2015
450
It seems it's a kind of interference pattern. I've never noticed it with single color led, but with the RGB leds that change color automatically, speckling is very prominent. I guess my eyes aren't fooling me afterall.
 

Ian0

Joined Aug 7, 2020
3,186
I noticed it on an unlensed (flat top) LED which is the power indicator on my audio amplifier, if I look at it through my reading glasses (+1.5D) held at arm's length.
I've never seen it on a lensed (dome top) LED.
 

Tonyr1084

Joined Sep 24, 2015
6,243
With me - when red and blue are bordering each other it's difficult to distinguish the boundary. It's almost as if the blue is lit on the far side casting light onto the red, making it look illuminated. I AM "True Color Deficient" in my sight. Red and Green are difficult to distinguish between. Blue and Purple - I can't tell the difference without studying the color closely. IF I can see "Red" in the "Blue" then I know it's Purple. Otherwise it's going to be Blue.

Eyesight is a funny thing. Rods and cones in our eyes detect light differently. I think the "Rods" detect varying levels of grey from white to black. Cones are specialized in color reception. Some people have a good mix of cones while others may be "deficient" in some cones that detect certain wavelengths of light (color).
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Audioguru again

Joined Oct 21, 2019
3,505
When I became 45 years old my vision needed closeup glasses like most middle-age people. Then 5 years later I needed close, medium and far triple focal lenses in the glasses.
Suddenly I saw bright speckles on lighted objects which I thought were caused by damage to the glasses but the speckles were still there with the glasses removed. Then my vision got so cloudy over a few months that I became completely blind with cataracts.

Cataracts normally begin with the eye lenses becoming stiff and cannot focus then a little later become cloudy.

The eye doctor removed the useless lenses in my eyes and replaced them with synthetic lenses. Then my vision was perfect except sometimes I use closeup glasses. Today new expensive synthetic lenses can focus the same as original eye lenses then glasses are not needed.
 
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