Looking for: Tiny 5-7 mm AR coated Right Angle Prisms for Green.

[Laser57]

I’m looking for small 5 to 7 mm AR coated (all sides) right angle prisms to use for total internal reflection. Anyone know a source at a good price? If not coated, uncoated? If I find inexpensive uncoated right angle prisms, I can probably find a telescope optics shop to AR coat them as well as add a mirror coating to the hypotenuse side.

Reality is I only need the legs AR coated without any mirror on the long side/hypotenuse, but mirrorizing that side along with AR would also allow knife edge use. Anyone interested in a group buy?

I found these on ebay which are without AR coat but I am not yet certain they can be used as turning prisms as they were made for external reflection: https://www.ebay.com/itm/114404132109 - Also, I much prefer a lower loss dichroic (which these aren’t) HR for knife edging, but it is possible the existing mirrored side might be fairly high reflectance or low loss. I like 98% transmission or better.

Any recommendations? EdmundOptics are too expensive for my budget and don't have a good selection for the smaller sizes, lasertack doesn't sell them with AR coating on all sides or intended for total internal reflection use. SurplusShed.com doesn't have them and I need a quantity of 16 each. I need the legs AR coated, this is paramount.

Good news though, Thorlabs offers them at 10 mm which although larger than I want, would work, but damn, not cheap: https://www.thorlabs.com/newgrouppag...ctgroup_id=142

N-BK7 Right-Angle Prism, L = 10 mm, AR Coating on Legs: 350-700 nm

80,42 €

At that price, I will forgo using prisms and just use mirrors. I just wanted internal reflection prisms due to their extreme low loss, if AR coated, as well as no fear of burning the internal reflective surface from contaminates, although the AR could be damaged that way anyhow.. Lasertack has some broadband multicoat dielectric mirrors now, first time I've seen dielectric with a broad bandwidth for VIS and a bit beyond; 440-700 nm. Here's a link, but he's still using the photo and specs of his older product on the web page which were not broadband, but the drop down, if ordering, shows the wider range: https://lasertack.com/en/dielectric-...e-mirror-prism