The old fashioned mice worked via two wheels that are turned by a ball:
One represented the x-axis while the other represtened the y-axis. Turning one, would move the mouse in that specified direction. Moving both resulted in a combined and (somewhat) smooth movement of the mouse.
With the advent of Lasers and optics, we now more commonly use the 'Laser Mouse'. How do they work exactly? How does a laser light and moving of the device translate into those x and y values for movement on the screen?
Detailed explanations are welcomed.