Logitech MX1000 Review - What's normally under the hood
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It's what's under the hood that makes a real difference here. Typical ball mice function by tracking the motion of the little round object inside them. They do this with an "opto-mechanical" method. The little ball rolls, and two "rollers," one for the x axis and one for the y axis track its movement, and turn shafts which attach to a wheel. Through holes slotted in the wheels, infrared light shines, and is picked up by an optical encoder. Another sensor picks up direction of movement, and combining those two values (direction and speed) for each direction, the mouse can send along data to its driver.
That's what I use for my SUN machine, and has been used on my parents' crappy old computer since the days I was a wee lad. However, that technology has been replaced for the most part in any modern PC. With what? Well, the "mechanical" part has been removed from the equation. For any of you fortunate to grow up on old equipment, you'll remember that cleaning the mouse was a gigantic pain in the arse. I hate doing it. And, as with any mechanical device, they eventually break from wear and tear, or at least just get next to useless.
A straight "optical" mouse, however, isn't going to have the movement part suffer from that. Instead of wheels, rollers and balls, an "optical" mouse basically takes pictures of the surface on which it's mousing. Using a small red LED and CMOS sensor, the mouse actually "looks" at what it's on top of. By comparing one picture to the next in sequence, the mouse's on board processor is able to figure out how far it moved from one frame to the next. The resolution is limited by the precision of the sensor, how fast the processor can compare images and decide the new co-ordinates, and the power of the LED.
Next: Logitech's MX Laser Engine and FastRF technology >>
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