[cornholio]

Interesting. The drawbacks you describe seem to be limitations of the sensor and image processing technology available almost 30 years ago.

For example, my Epson inkjet printer can do about 10ppm at it's lowest print quality, so it can mechanically move and scan a page against the printhead every 6 seconds; a 1Mpx sensor with a 60Hz frame rate will generate 360Mpx in 6 seconds. Even if you throw away 50% of the data (overlap areas, next page load, motion or optical blur at the edges etc.), that's still enough data for a ~1400 dpi raw resolution of an A4 page at the fastest speed. If you are willing to go slower, the resolutions the system could achieve seem outside the range of any flatbed.

Of course, you would need e very beefy image processor to handle the multiple Gbps raw video data and process in real time down to the final scan image, but the actual corrections seem very achievable with modern algorithms.

Outside of the cost of the image processor, another showstopper I can see is motion blur on the sensor, stopping the heavy printhead from its inertia, so that you can have a still image, will kill your total scan speed. But perhaps you can just pulse the LED, or a gas discharge lamp, and impress the sensor with near instantaneous flashes of light.