Fezz, that sounds awfully compelling. I vote that you're right.
Fezz, that sounds awfully compelling. I vote that you're right.
In some cases, you can have even lower reflectance with AR on high-index lens materials if they more closely satisfy the amplitude condition of the available coating materials. Although this is less of an issue with multi-layer coatings.
Darryl J. Meister, ABOM
That confirms it. Thanks, D-man.
You guys are good at coming up with these thought-provoking questions.
Darryl J. Meister, ABOM
Not to breach etiquitte, but please see the minus aspherics thread, Darryl. It needs you.
Perhaps you could elaborate on this a bit (I'm assuming you're still referring to a transparent coating).Originally Posted by Chris
Darryl J. Meister, ABOM
1/4 in and 1/4 out will put the wave a total of 1/2 out of sequence creating destructive interference.
or tato chip it down for me.
Here is a quick mock up.
1st* HTML5 Tracer Software
1st Mac Compatible Tracer Software
1st Linux Compatible Tracer Software
*Dave at OptiVision has a web based tracer integration package that's awesome.
:d
It is correct if we are talking about optical thickness. If light is split into two components by reflection at the top and the bottom surface of a thin film (AR coat), then the beams will recombine in such a way that the total amplitude will be the difference of the amplitudes of the two components. We say that the beams interfere destructively if the relative phase shift is 180 degree. To ensure that the relative phase shift is 180 degree, the optical thickness of the film should be one quarter of wavelength. What is important here, it works when the reflection will take place in a medium of lower index then adjoining medium.
"1/4 in and 1/4 out will put the wave a total of 1/2 " it is true if we consider optical way, but optical thickness is stiil the same- one quarter of wavelength.
Best regards,
Julian
We should clarify that "optical thickness," or more specifically, optical path length is the product of the physical thickness and the refractive index of the film.
Darryl J. Meister, ABOM
we discussed a lot of the A/R theory in this thread as well
http://www.optiboard.com/forums/showthread.php?t=13188
AA
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