Microsoft's Optical Approach

Build a better mouse…

From a design standpoint, an optical mouse is really a good idea. As mentioned, it removes any and all moving parts, and it never needs to be cleaned. The only question is how to work around its various limitations.

The biggest problem to solve was the cumbersome mousepad. Microsoft solved this problem by using a special CCD device. A "charged coupled device" is the mechanism used in a digital camera to capture a picture. So in essence, the MS Optical mouse is a very specialized digital camera. The camera is designed to take very fast snapshots of the surface under the mouse. It then compares the last two pictures and specialized firmware determines the difference between the pictures and translates it into positional movement.

Introducing the IntelliEye

The go-anywhere mouse

Intuitively, doesn't it sound like just about any surface will do? Well, yes, and that's one of the biggest advantages of the mouse. The camera can identify the microtextures of almost any given surface, and accurately determine speed and position. The only thing you need to worry about is what surface gives you the most comfortable feel.

I saw a bright light

An unearthly red glow on the bottom of the Intellipoint Explorer is the product of a bright LED used to illuminate the target surface. The light is set at a 10-15 degree angle from the CCD, to better show in profile the contrast between the tiny ridges and valleys on a typical surface.

Giving you the evil eye

The red LED also tends to be very bright - of the same caliber used in high-intensity LED keychains. In essence, it's bright enough to potentially cause eye damage with prolonged exposure. In order to save people from themselves, Microsoft programmed the mouse to dim the light after a 1 second delay if the CCD cannot focus on a target. The dimmed light is still very bright however, and peering into the LED is certainly NOT recommended.

Just for kicks, an additional LED is placed at the butt of the mouse to accentuate the glow for passersby. Along with the city-light looking underside, it gives the IntelliMouse Explorer a slightly ethereal look.