I've wanted, for a long time, a microscope for photographing small things in which I am interested such as micro circuits.  Off the shelf USB microscopes have low pixel counts and for any given image, there is a trade off between magnification and field of view:  I can have good magnification on the order of 100x or I can see the whole die in a single image at low magnifications of 10x or so.  To get both, you're forced to tile many high mag images which is an arduous and inexact process with severe issues with illumination.

This project is to take a working scanner with a 10,800 pixel color line sensor and retask it's mechanics (A stepper motor that was set up to pull the scanning head across an 8-1/2 x 11 page) and redesign it's optics for magnification instead of reduction.  The sensor is 38mm wide and the target size will be 6x8mm.  The mechanics is easy, just gear down the stepper motor such that 150 revolutions of the output shaft will drive a linear stage 8mm while the sensor width sets the 6mm limit.  This will yield an optical resolution of 550nm with an interpolated resolution (via the scanner electronics) of 138nm.  The focus mechanism of the optics, a single acromat lens, will consist of simply moving the lens up and down while the sensor and object remain stationary.  Essentially, the end result will be a 155 mega pixel camera.