WARNING This post involves lasers that can, depending on their power be dangerous to your eyes. Doing this modification carries a very high risk of destroying your module. This modification will definitely void your warranty if there is any left. The modification can not be reversed.
I have found a modification that lets you use your Fairphone or any other phone as a microscope.
The modification involves removing the lens over the front camera and reassembling the module without damaging the exposed image sensor. If you then use a laser to illuminate a sample that you place on the screen, you will be able to use the camera as a microscope with a resolution of a few micrometers.
The trick is to remove the lens that usually focusses the image onto the sensor by screwing it out of the camera module completely without damaging the image sensor underneath which is completely exposed at this point. It is litterally just the exposed silicon and just touching it destroys it immediatelly. It is really that fragile, any dust that lands on it is almost impossible to as it only takes a minimal amout of force to damage it. If you are doing this with the newer version of the top module, then you have the advantage that the sensor isn’t directly exposed, you will still have a filter over it. But if you do this with the old module, the the sensor is completely exposed, it looks very odd, it basicly shines in all the colours of the rainbow, but at the same time looks kinda rough. This is because over each individual pixel there is a small lens.
I have done this modification before, but only with the IPhone 5S, not the Fairphone 2. When I did this with the IPhone, I used the rear camera. This had the dissadvantage that I could no longer take normal photos and that you had to hold the phone at a weired angle so that the sample doesn’t fall off. This is no longer an issue now.
For the laser, you can either use a high powered laser and shine it at a distant wall, for this purpose the laser should have at least 5mw, or you can illuminate the sample directly with the laser. For this purpose a laser with well under 1mw is sufficient, but the requirements for the beam specs is very high if you want to get good images.
I have made some test, both with the IPhone and the Fairphone.
The photos from the IPhone are the drop of blood, the flys leg, the hair and the skin cells and the photos from the Fairphone are the screw from the Fairphone, a hair, two photos of dust, the point of a broken off toothpick, the holes in the fabric of a headband and the lines on a transparent ruler which are exactly 1mm appart.