Working of an Optical Mouse

To understanding its working, we should note how the mechanical mouse works. The mechanical mouse contains a ball which partially protrudes from the bottom surface, so that the ball rotates as the device is moved, internally actuating two pick-up elements which convert the motion to its `x’ and `y’ components and sends impulses to the computer that causes a mouse-responsive program to reposition a cursor on the display screen.

In principle, an optical mouse works almost same a mechanical mouse, but the working is entirely different. Optical Mouse was developed by Agilent Technologies and introduced in late 1999. It actually uses a tiny camera to take 1,500 pictures every second. Thus, Optical Mouse used Camera Technology and digital processing to compare and track the position of the mouse.

Pictures counting about 1500 per second are taken by bouncing light from a small, red light-emitting diode (LED) off the surface under the mouse, and onto a Complimentary Metal-Oxide Semiconductor (CMOS) sensor. The sensor sends each image to a digital signal processor (DSP) for analysis. DSP compares the pictures and determines the speed and direction of movement and sends the corresponding coordinates to the computer.

The most visible benefit of an optical mouse is that it has less wear due to elimination of moving parts, and it does not require a mouse pad (unless u we use a glass surface) and can be used on many surfaces, including those that are not entirely flat. The sensing in optical mouse is more precise.

• A Laser mouse is an optical mouse that uses coherent (Laser) light.
  

Cordless mice instead transmit data via Infrared Radiation or radio (including Bluetooth)