Introduction
Based on the RPI camera and LEGO brick-based microscope I had presented earlier ( A-Raspberry-Pi-camera-based-microscope-built-from- LEGO ), I have constructed a similar microscope build from Plexiglas parts. So now you may build your microscope even w/o having a large LEGO collection. One thing missing in this prototype is the adjustment gears of the LEGO version.
The maximum resolution of the microscope is about 5 Β΅m/pixel. At high resolution only a small area will be in focus and you will see an effect called chromatic abberation. You may use this microscope to analyse objects in the range from a 20th of a millimeter to 5 mm. This means fruitflies, hair, salt and dust, but not individual cells, e.g. from blood or cell culture.
Below you will find a description of the device and the information necessary to build one on your own.
The prototype version presented here had been constructed in a way that would allow easy assembly from pre-produced parts and subsequent disassembly, as long as long the parts are not glued together. This was intended to allow modification and optimization the microscope, and adaption for special applications, if required.
I am currently working on a simplified version that will be easier to assemble and a bit cheaper in production. In addition I am working on better illumination and the optimization of the optics. My aim is to design a building kit that would enable a science class to build their own microscope, at costs (w/o RPi) of << 100 β¬.
Let me know if you would be interested in the kit, or just the SVG files and instructions, and please indicate if it should be used for educational, private or research or commercial use. Any ideas for improvements as well as for science projects, like time lapse videos of the growing crystals or mold, would be welcome.
Parts needed:
β a Raspberry Pi 2, keyboard, mouse, monitor or TV
β a WaveShare B-camera (WaveShare B), I got mine at Sertronics, Berlin, Germany, and a 50 cm camera cable.
β a set of pieces cut from 3 mm acrylic/Plexiglas plates, as defined by the SVG files (see Step 5).
These could to be ordered at your local laser cutting service, e.g. Ponoko in the US, Formulor in Germany or RazorLab in the UK. Just upload your SVG-files at their web site and order.
β a set of pieces of 10Γ10 mm Plexiglas beams (in total about 170 cm), available e.g. at Modulor, Berlin.
β a number of Plexiglas sticks/dubles with a diameter of 3 mm and a length of about 8 mm and/or
β glue for Plexiglas, as dichloromethane (handle with care, it is toxic!) and/or super glue
β six 10 mm M2 screws and ten M2 nuts. M1.6 screws and nuts would be better, but are not so easy to get.
β for illumination: a 1,6 W LED lamp (12 V), a 9 V block battery, cable and battery adaptor, a small switch.
Costs:
β the WaveShare B-camera is available for 22 US$ at WaveShare, or for about 25β¬ at Sertronics.
β the laser cut plates will cost about 30β¬.
β 2 m of the 10 x 10 mm acrylic beams cost about 14 β¬, e.g. at Modulor, Berlin
β M2 screws and nuts, about 5 β¬ (Bauhaus, Berlin), M1.6 x 10 screws and nuts: about 11 β¬ (Conrad.de)
β a Raspberry Pi with SD card, keyboard and mouse will cost about 60- 70 β¬ (in case you do not have one already).
Basic layout:
The microscope consists of a base plate, a sled tray for objects or object glasses to be placed on and a βtowerβ to hold the plate on which the camera is mounted. Object sled and camera plate can be moved orthogonal to each other, allowing precise placement of the camera above the object. To focus the camera, you must manually turn the camera objective. I had placed a LEGO rubber wheel at the objective to get a better grip.
To adjust the distance between object and camera you may place the object on a tray with a certain heigth or, for a permanent solution, may adjust the length of the colums of the camera tower.
The majority of the parts can be ordered via internet at laser cutting services as Pokono.com, Formulor.de or RazorLab.co.uk and are made from 3 mm acrylic/Plexiglas. I have attached a description as pdf and the required SVG files, which are based on the 181 x 181 mm (P1) plate form used by Pokono, Formulor and RazorLab.
For more detail: ARPM: Another Raspberry Pi Microscope