Ask HN: Tiny extreme macro camera for Arduino etc?

Looking for a recommendation on a camera or lens, photo cell or similar sensor that can do extreme closeup capture of a surface, while sitting as close as possible to the surface.

It would be mounted on the face of a piece of equipment, pointing inward, on a gauge or panel to capture it's output/status.

For example, a small LED panel on a stereo, the camera would be mounted on the face to capture it's current reading in an analog way.

Minimum quality needed would just be to differentiate between different readings. Software would take over after that.