As some of you know I am no longer working at the university on the microscope full time. I am now a freelancer, and am trying to find as much time as possible to work on open projects.
Recently experiment.com launched a low-cost tools for science challenge on their crowdfunding site. They want people to develop new tools. One thing we are regularly asked for in the OpenFlexure project is a microscope to look at bigger things like bugs and circuit boards. When we took the OpenFlexure to Panama, we met scientists studying orchid bees using dissection microscopes, they would love a low-cost portable microscope they could take into the field.
Working with Andy Quitmeyer who runs a field station in Panama, we have launched a fundraiser to develop an OpenFlexure-family Dissection Microscope:
The microscope will:
Be totally open so you can build one yourself
Have clear documentation to enable it to be built easily
Focus on good quality mechanics so the microscope is easy to use
If you are able to, please consider supporting us.
I guess a bigger working distance may be needed for this application. As part of the design process for a microfluidic workstation, we tested the RPi cam and other lenses to keep a compact design.
Here is a little contribution to community knowledge:
I’ve definitely spent quite a lot of time answering people who are curious about a lower-magnification system, and explaining that OpenFlexure could do it, but there are probably much better ways to do it. It would be awesome if Julian was able to come up with something that solved this problem with his customary quality of engineering
Playing with different lenes to increase the working distance is key. I am hoping to mechanises the lens to camera distance for some level of variability of the magnification. Some of this will involve some calculations, I think it might be possible to use pyoptic2 for this.
I think the first port of call is to create a sturdy frame with decent quality motion. And then to create a parametric design for the camera/lens mount that makes it easy for users to experiments with lens configurations.
Yes so these projects are what made me think we needed to start again from the mechanics side. Both of these show quite well that the performance of a simple camera and lens held above the sample is good and useful. However I don’t think @r.w.bowman or Andre would be insulted if I said that neither of these systems has been designed around robust ergonomic mechanics.
I want to create a system that has the main z motion control driven by a rack and pinion, via decent sized handles, in a way that is self locking so that the user can easily focus in the field. Variable magnification would be a bonus.
Definitely not offended The dissection microscope was knocked up in an afternoon in response to someone asking if they could look at microplastics. As @j.stirling says, the optics were more or less OK, but the mechanics were rubbish. I think a lot of the appeal of OpenFlexure is that it “gets the mechanics right” but currently that’s only really true for high-power microscopy (i.e. fields of view well below 1mm). For lower magnification work, something with a nice rack and pinion stage would be ideal - and I’m not aware of many examples of that.
FlyPi is probably closer - but again I don’t think it’s mechanically optimal. At least the version I built (which was a while ago) just slid the camera up and down on a rod, and locked in place with a screw - fine for doing a timelapse or taking videos (which, to be fair, is what it was designed for), but less ideal for interactive use where you’re adjusting focus frequently.
Talking of looking at microplastics (or other larger samples). If you want something less portable than what I am hopefully going to work on, but far more automated there is the 3D printer based microscope Niamh Burke is working on in Mark Pickering’s lab.
They are currently working through making the documentation in GitBuilding I don’t think there is a version online. But it is incredibly cool. She uses the fine motion control and electronics of an Ender 3D printer, with the optics clipped on where the print head goes. Even cooler, the clip is designed so you can quickly swap between printing and microscopy.
