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Entry  Sun Jul 7 21:59:28 2019, Kruthi, Update, Cameras, Ghost image due to beamsplitter ghosting_schematic.pngBeamsplitter_spec.pdf
    Reply  Mon Jul 8 21:42:39 2019, rana, Update, Cameras, Ghost image due to beamsplitter 
Message ID: 14732     Entry time: Sun Jul 7 21:59:28 2019     Reply to this: 14735
Author: Kruthi 
Type: Update 
Category: Cameras 
Subject: Ghost image due to beamsplitter 

The beam splitter (BS1-1064-33-2037-45S) that is currently being used has an antireflection coating on the second surface and a wedge of less than 5 arcmin; yet it leads to ghosting as shown in the figure attached (courtesy: Thorlabs). I'm also attaching its spec sheet I dug up on internet for future reference.

I came across pellicle beamsplitters, that are primarily used to eliminate ghost images. Pellicle beamsplitters have a few microns thick nitrocellulose layer and superimpose the secondary reflection on the first one. Thus the ghost image is eliminated. 

Should we go ahead and order them? (https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=898


Attachment 1: ghosting_schematic.png  29 kB  Uploaded Mon Jul 8 22:32:56 2019  | Hide | Hide all
Attachment 2: Beamsplitter_spec.pdf  179 kB  Uploaded Mon Jul 8 22:34:02 2019  | Hide | Hide all
Beamsplitter_spec.pdf Beamsplitter_spec.pdf
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