YOU CAN PRINT A MOTORISED LAB MICROSCOPE AT HOME — AND IT IS ALREADY USED IN MALARIA RESEARCH
A fully motorized microscope you print at home, already being used in malaria research in Tanzania.
by OpenFlexure Project, University of Bath
ScienceOpen-hardware
Built withRaspberry Pi3D printing
- difficulty
- ●●●●○
- time
- a weekend-plus
- license
- CERN-OHL-S
- repo
- repo ACTIVE0 stars
●●●●○ · a weekend-plus · CERN-OHL-S · 0 stars · repo ACTIVE
WHAT YOU’LL NEED
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COMPAREE VERDICT
OpenFlexure is the rare open-hardware project that has moved from the university lab into real-world medical research. The University of Bath design uses printed flexure joints — thin plastic hinges that flex rather than slide — to position the stage in sub-100-nanometre steps, which is why it does not need bearing rails. A Raspberry Pi drives the motors and camera, so the scope can scan a whole slide autonomously. In Tanzania, BongoTech manufactures them locally and the Ifakara Health Institute is evaluating them for malaria diagnosis. The current v7 build is labelled beta, and rightly so: you are assembling a precision instrument from plastic, cheap steppers, and friction-fit optics, then asking it to hold sub-micron focus. Most of a weekend will be tuning backlash and getting the illumination even. If you want a ready-to-go USB microscope, buy one. If you want to understand how a microscope works — and contribute to an open hardware project already used in malaria research — this is the one to build. The single hardest part is not the print or the assembly; it is accepting that your first calibration will drift and you will need to go back in.
IN THE REPO
GOOD TO KNOW
- —CAD files for the body and stage are in the GitLab repo; printed flexures replace all metal rails.
- —Bill of materials lists the Raspberry Pi, camera module, stepper motors, optics, and fasteners — sources included.
- —Python-based server software runs on the Pi; autofocus and whole-slide scanning are built in.
- —Build guide, assembly videos, and user documentation are all present; the project labels v7 as beta.
- —Licensed CERN-OHL-S (strongly reciprocal); commercial manufacture allowed but derivative designs must share-alike.
- —Peer-reviewed in multiple journals including Biomedical Optics Express 2020 (best paper award).
Parts to buy
9 itemsFrom our check of the build. Exact quantities and part numbers are in the creator’s BOM.
Can I build this?
Build at your own risk. Projects involve tools, electronics and sometimes mains voltage — follow the creator’s safety notes.
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Start here
Navigation into the creator’s own docs — we don’t rewrite the guide, we route you to the source.
- 1.Read the build guide on openflexure.org and verify your Pi and camera module are on the compatibility list (The v7 beta docs call out known Pi and camera combinations that work; starting with untested hardware wastes the weekend.)
- 2.Run the printer test from the build guide, then download the STLs and print them in PLA with 0.2 mm layers, a 0.4 mm nozzle, no supports and your printer's default infill; print the optics module in black (The flexures need clean layer adhesion — poor infill or wet filament will cause them to crack under load.)
- 3.Order the bill of materials early; objective lenses and stepper motors often have two-week lead times(The BOM is in the repo docs folder.)
- 4.Assemble the stage and flex it by hand before installing motors — you are checking for binding(If a flexure binds or snaps during dry assembly, reprinting one part is easier than debugging it later.)
KNOWN ISSUES
- Skipping the printer test in the build guide — the flexures and nut traps depend on accurate prints, and a badly tuned printer or damp filament gives parts that bind or crack.
- Buying a non-RMS-thread objective or a camera module not listed in the compatibility table — the optics module is designed around specific thread pitches and sensor sizes.
- Expecting plug-and-play autofocus on the first boot — the motor calibration and backlash compensation need tuning, and the docs are honest that v7 is still beta.
- Overtightening screws into printed parts — plastic strips and cracks easily, so tighten only until you feel reasonable resistance, as the build guide's printer test describes.
- Skipping the optical alignment step and wondering why one corner of the field is sharp and the other is not — the condenser height and lens spacing both matter.
- Assuming clinical-grade performance out of the box because it is being evaluated in Tanzania — those units are tuned and maintained by people who built dozens; your first one will be a learning build.
What magnification can this achieve?
Depends entirely on the objective lens you install — the optics module accepts standard RMS-thread objectives, so 10×, 20×, 40×, and oil-immersion 100× are all possible. The docs recommend starting with a 10× air objective for alignment.
Can I use a Raspberry Pi Zero or an older Pi 3?
Use a Raspberry Pi 4. The current OpenFlexure software (v3) supports only the Pi 4 with 4 GB of RAM, not older Pis or the Pi 5. The older stable v2.11 release still runs on a Pi 2 Model B or newer, with a Pi 4 recommended. The details are on the install page at openflexure.org.
Is this actually being used in clinics?
Not as a certified diagnostic device. BongoTech in Tanzania manufactures the microscopes locally and the Ifakara Health Institute has used them in a research study imaging stained blood smears for malaria, with the stated goal of eventual medical certification; the openflexure.org malaria page names the partners. It is past the proof-of-concept stage, but it is not a certified medical device.
Do I need to calibrate it every time I use it?
No — once the backlash compensation is tuned and the optics are aligned, it holds calibration across sessions. But the first-time setup is not five minutes.
Can I sell microscopes built from this design?
Yes, the CERN-OHL-S licence allows commercial manufacture, but any modifications you make to the design must be released under the same licence — it is strongly reciprocal.
Community builds
No community builds yet — be the first, we feature the best ones.
Discussion1
FROM THE COMPAREE TEAM
Steps well below 100 nanometres from printed plastic flexures, and the microscope is being evaluated for malaria diagnosis in Tanzania. If you built one, what would you point it at first?
OpenFlexure Project, University of Bath
Richard Bowman and collaborators in Glasgow, Bath, Cambridge and Dar es Salaam developed OpenFlexure to make precision microscopy accessible in low-resource settings. The design has been peer-reviewed in journals including Biomedical Optics Express (2020 best paper) and is now manufactured locally in Tanzania for malaria research, working towards medical certification.
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DISCLAIMER
- Comparee is not the author of the projects featured here. All rights to each project belong to its creator — every page links to the original source, and we never host creators’ files.
- Information is provided without warranty and may become outdated as projects evolve. Prices are indicative bands only — always check the creator’s parts list for current costs.
- Building and operating any project is at your own responsibility. Protective equipment, safe workshop practice and compliance with local regulations are the builder’s responsibility.
CompareeTEAM2mo agoedited
Practical notes from our verification: the project lives on GitLab, not GitHub, and the build instructions are on build.openflexure.org. There is an official OpenFlexure YouTube channel linked from openflexure.org, and the community forum is the place for build questions. The current v7 release is still labelled beta, which is fair: this is a precision instrument that needs tuning, not a kit you assemble in an afternoon. The high-resolution version uses three 28BYJ-48 stepper motors, a Sangaboard motor controller, a Raspberry Pi 4 and the Pi Camera Module v2, and the BOM lists about 400 g of PLA. Print quality matters for the flexures, so dry filament and the recommended settings are worth the effort before you start. The microscope is being evaluated for malaria diagnosis in Tanzania, but your first build will need iteration before it performs like those units. Correction (4 October 2026): we re-checked this page line by line against the project's own repository, documentation and videos, and fixed errors in earlier versions.