One Laptop Per Child XO-4 Focus Jig

Macrophotography on the One Laptop Per Child laptop.

Inspired by the OLPC San Francisco experiments with an acrylic cabochon lens, as well as Bill Tuk and Sameer Verma's focus jigs, I set out to design and 3D print a focus jig that could be "mass produced" through additive manufacturing. 

Bill Tuk's original design was beautiful and amazingly functional. However, it was difficult to replicate.
I started with the lens kit and a 3D printed viewfinder design I previously created. http://www.thingiverse.com/thing:217128
I added a part to the viewfinder design to see if it would hold the lens in place.
A popsicle stick with a small hole drilled in it and sandpaper glued to it served as the part of the jig that would raise and lower to focus the object the jig holds.
A paperclip and a pencil eraser are parts that should be found in most any school anywhere in the world. The goal was to produce the focus jig without too many unique parts, with the exception of the 3D printed parts.
The final design was printed in two parts. One part slides into the USB port for support.
The second part is super-glued to the other ABS plastic piece. It holds the cobachan lens in place over the laptop camera lens.
A small piece of coaxial cable insulation over the eraser helps reduce wear on the eraser from contact with the sandpaper. 
A coat hanger bent into the correct shape and secured with a washer, nut, and bolt serves as the platform on which the item to be magnified can be set.
Properly bent, the platform is spacious.
The object is set on the platform. The eraser dial moves the object away and towards the lens. The Record Activity on the XO laptop is used to take the photo.
The level of detail is impressive.
1963 US quarter dollar.
Macrophotography reveals impressive details normally overlooked.

The files to 3D print your own focus jig are available from Tinkercad.com.


Focus jig part 1.


Focus jig part 2.


I printed my focus jig with Inventables 3mm ABS plastic on a MakerBot Thing-O-Matic and used Testor's model glue to glue the two pieces together.