I found a broken cell phone with it’s camera and wondered if the lens could be used as a microscope objective. Image A shows the lens and it’s mounting with the CCD. The back of the lens is shown. The lens is about 4 to 5 mm in diameter.

The starters from florescent lights make good lens holders. Image B shows a starter along with my modifications to hold the cell camera lens. The starter tube has 4 slits along the length so it can be compressed to fit the turret of the microscope. Image C shows it mounted on the turret.

Image D shows the resulting view of a feather. It’s quite bad. Image E shows, for comparison, the view through an ordinary 20x objective (.40 NA).

Here are some more lenses that I tried:
Lens from a discarded flatbed scanner..... Very good!
Lens from a 8mm movie camera...... Fair.
Lens from the laser pickup of a discarded CD player..... Almost worthless.

To take pictures through the microscope, I used eyepiece projection with a wide angle eyepiece. The lens on the camera was set to wide angle and maximum aperture, with a remote used to trigger the shutter. The camera’s LCD was used to focus and adjust the image. The camera’s autofocus handles the rest. For even illumination, be sure to center the objective lens over the substage condenser.