Optical computer mouse

Listing ID #4409646

An optical computer mouse or "optic mouse" uses a light-emitting diode and photodiodes to detect movement relative to a surface, unlike a mechanical mouse which has a ball which rotates orthogonal shafts which drive chopper wheels for distance measurement. The earliest optical mice detected movement on pre-printed mousepad surfaces, whereas the modern optical mouse works on most opaque surfaces; it is unable to detect movement on specular surfaces like glass. Laser diodes are also used for better resolution and precision. Battery powered, wireless optical mice flash the LED intermittently to save power, and only glow steadily when movement is detected.

Unlike mechanical mice, which can become clogged with lint, optical mice have no moving parts; therefore, they do not require maintenance other than removing debris that might collect under the light emitter. However, they generally cannot track on glossy and transparent surfaces, including some mouse-pads, sometimes causing the cursor to drift unpredictably during operation. Mice with less image-processing power also have problems tracking fast movement, though some mice can track faster than 2 m/s (80 inches per second).

Some models of laser mouse can track on glossy and transparent surfaces, and have a much higher sensitivity than other mechanical or optical mice, but are more expensive than their LED-based or mechanical counterparts.

As of 2006, mechanical mice had lower average power requirements than their optical counterparts; the power used by mice is relatively small, and only an important consideration when the power is derived from batteries, with their limited capacity.

Optical models outperform mechanical mice on uneven, slick, soft, sticky, or loose surfaces, and generally in mobile situations lacking mouse pads. Because optical mice render movement based on an image which the LED (or infrared diode) illuminates, use with multicolored mouse pads may result in unreliable performance; however, laser mice do not suffer these problems and will track on such surfaces. The advent of affordable high-speed, low-resolution cameras and the integrated logic in optical mice provides an ideal laboratory for experimentation on next-generation input-devices.