Look into HP patents around 1990-99 on optical paper sensors. Afaik mouse sensor came from research into large format plotter paper tracking. US Patent 5,729,0

Look into HP patents around 1990-99 on optical paper sensors. Afaik mouse sensor came from research into large format plotter paper tracking. US Patent 5,729,008. Interview with inventor: Oral History of Travis Blalock https://www.youtube.com/watch?v=wmqa9XJED-Q https://www.youtube.com/watch?v=wmqa9XJED-Q https://archive.computerhistory.org/resources/access/text/2018/10/102717371-05-01-acc.pdf https://archive.computerhistory.org/resources/access/text/20... "each array element had nearest neighbor connectivity so you would calculate nine correlations, an autocorrelation and eight cross-correlations, with each of your eight nearest neighbors, the diagonals and the perpendicular, and then you could interpolate in correlation space where the best fit was. " all in analog domain another one from HP/Agilent/Avago: Oral History of Gary Gordon https://www.youtube.com/watch?v=TxxoWhCzIeU https://www.youtube.com/watch?v=TxxoWhCzIeU also this https://blueironip.com/hp-capshare-how-a-failed-product-yielded-huge-revenue/ https://blueironip.com/hp-capshare-how-a-failed-product-yiel...