coating in pyrex lens

Kiu

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Jan 11, 2003
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The coating in my E1e lens seems reflect a purple in colour.
however, the coating that in my E2e lens is appear yellow green.

What is the difference??or why
which is better? purple?
 

flashlightlens

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A Magnesium Flouride (MgF2) coating will usually give off a purple reflection. BUT, multi-layer coatings can also give off a purple or blue reflection. I'm assuming it's MgF2, since this type of coating is fairly inexpensive.

The yellow/green tint indicates some sort of multi-layer coating.

As far as performance, the coatings will reduce reflections down to anywhere from 1.5 to 5%. Normal glass reflects somewhere around 5%.

Chris
 

Kiu

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Originally posted by Onyx:
have you tried changing the angle of incident, ie. looking at it from a different angle? Does the colour change?
<font size="2" face="Verdana, Arial">yes, i hv try for both for any angle
but still one purple another yellow green
also i try lexan lens is no coloured
 

yclo

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I have tried on mine too, and I do get green for one and purple for another. I think it's just that the coating was done at different times?

-YC
 
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