pinholing a ball lens?

Light and its behaviour and properties
Joe Farina
Posts: 804
Joined: Wed Jan 07, 2015 2:10 pm

pinholing a ball lens?

Post by Joe Farina »

I was wondering if anyone has tried to spatially filter a ball lens. I need a highly diverging reference beam. A 100x objective will provide approximately enough divergence, but 125x or 150x might be better. So far, it's been difficult to spatially filter 100x objectives (although my spatial filter is a cheap one with screws instead of micrometers).

It looks like ball lenses can provide the right kind of beam expansion, but I would need to modify my spatial filter to accommodate one. When first starting out in holography, I managed to build a homemade spatial filter with a lens and a pinhole (aluminum foil). Edmund has a short tutorial on ball lenses: http://www.edmundoptics.com/technical-r ... all-lenses