The technique of edge-illuminated darkfield has been discussed, and experimented with, here before, so here is (yet another) article from a journal having to do with a research lab application:
https://journals.plos.org/plosone/artic ... ne.0116925
Edge-lit darkfield journal article
Re: Edge-lit darkfield journal article
Thanks for the link ... PDF duly downloaded
This remains a fascinating topic
MichaelG.
This remains a fascinating topic
MichaelG.
Too many 'projects'
Re: Edge-lit darkfield journal article
Thanks wporter for the link.
I scantily read the article. Having read the previous Kawano's articles on this matter, and having constructed and experimented with a very crude DIY of the DIRI with simple means, I have some thoughts.
1. The original idea was fascinating indeed, yet it seems that much effort has been invested to optimize the performance. Just guessing, the width of the beam, its intensity and the angle at which it is directed towards the slide's edge are the chief challenges. Even in this new article, the device is not the same one that was described back in 2013 or 2015.
And, although it is described as a commercial Olympus-made apparatus, I am not clear whether it is actually for sale. It is apparently bundled with an automatic slide loader and/or scanner (perhaps as options). Likely, its price will reflect the above.
2. I am not clear on the maximum objective NA that can be used to provide good darkfield with the DIRI. Should re-read very carefully to find out. The previous article from 2015 or 2013 seemed to promise an NA of 0.95-1 for DF. But I could be wrong.
3. Microfluidic itself, separately, is a very extensive and active field of technology, but very difficult to accomplish at amateur level, because of the facilities required. There are disposable commercial microfluidic devices, from IBIDI among others, that are mostly aimed for inverted microscopes. Anyway, the microfluidic channels and wells indeed occupy considerable space, and if DIRI can illuminate all its area, it would be an advantage over condenser-based DF.
I scantily read the article. Having read the previous Kawano's articles on this matter, and having constructed and experimented with a very crude DIY of the DIRI with simple means, I have some thoughts.
1. The original idea was fascinating indeed, yet it seems that much effort has been invested to optimize the performance. Just guessing, the width of the beam, its intensity and the angle at which it is directed towards the slide's edge are the chief challenges. Even in this new article, the device is not the same one that was described back in 2013 or 2015.
And, although it is described as a commercial Olympus-made apparatus, I am not clear whether it is actually for sale. It is apparently bundled with an automatic slide loader and/or scanner (perhaps as options). Likely, its price will reflect the above.
2. I am not clear on the maximum objective NA that can be used to provide good darkfield with the DIRI. Should re-read very carefully to find out. The previous article from 2015 or 2013 seemed to promise an NA of 0.95-1 for DF. But I could be wrong.
3. Microfluidic itself, separately, is a very extensive and active field of technology, but very difficult to accomplish at amateur level, because of the facilities required. There are disposable commercial microfluidic devices, from IBIDI among others, that are mostly aimed for inverted microscopes. Anyway, the microfluidic channels and wells indeed occupy considerable space, and if DIRI can illuminate all its area, it would be an advantage over condenser-based DF.