Most of my posts relate directly to my research in one form or another. However with some I just like to share information that I am unlikely to use myself, but may be of use to the work that someone else out there is doing. Today’s post falls into this second category.

There is a microscopy technique called Differential Interference Contrast (DIC) which many hail as being amazing and producing unique and fascinating images. There are various online resources which go more into the theory of this (such as the Leica site here). It’s quite complicated to do and requires some very expensive components, and as such this pushes it out of the realm of many microscopists (myself included). However given its complexity and my scientific curiosity I do keep an eye out for parts occasionally, and I recently managed to get a few prisms from an Olympus Epi NIC (Nomarski Interference Contrast, which is Olympus’s name for DIC) as I was wondering what the transmission through these looked like. I managed to get 4 prisms, one each for the 5x, 10x, 20x and 50x objectives. Unlike the usual astronomical prices which people often want for these, I get them for about £50 in total including one of the objectives. There are a bit beaten up, and will need re-gluing into their holders as the original glue has failed, however the filters themselves don’t look too bad. Below are the filters.

The transmission through the filters (as measured on my Ocean Optics FX spectrometer) is given below.

I had suspected that these filters would have good transmission down into the UV and indeed they do. So, they are not normal glass, but more exotic materials, presumably quartz. This undoubtedly contributes to the high prices for these items.

By the way, a technique called ‘oblique lighting’ can be used to produce pseudo 3D type images. While perhaps not as powerful as DIC, it’s results can be pretty spectacular, and it is much, much easier and cheaper to do. This is something I do for my diatom images (see my other website Diatom Imaging if you like microphotos of diatoms).

Anyway, a short post today just to share some info. If you have found this I hope it helps you with your work. As always, thanks for reading, and if you’d like to know more about my work, I can be reached here.