What is inside a Computer Mouse ?

Chances are if you are using a mouse to navigate around your computer that it's an optical mouse. It was invented in 1980 and has pretty much completely replaced the ball-guided mouse. An optical mouse works using microscopic imaging technology. First, a tiny camera inside the mouse photographs your desk or mouse mat. The red glow you can see if you turn it upside down is a red light-emitting diode (LED) inside that projects light onto the surface. When the light hits the surface and bounces back into the mouse it hits a complementary metal-oxide-semiconductor (CMOS). This sends a message to a digital signal processor (DSP), which closely analyses changes in the pattern of the surface. Once it registers a movement, it sends a signal to the computer, which translates that information into a cursor movement. These adjustments happen hundreds of times every second, so it follows your hand movements in extreme detail. On top of the mouse is usually either a wheel or a tiny rubber ball. These use the same technology as early ball-guided mice. Rotating the wheel or ball with your finger moves a couple of rollers. These are wired up to a processor which analyses how much each roller has moved and allows you to move a web page or document up and down or, with the ball-topped mouse, side to side. These technological developments have greatly helped day-to-day computing, making navigating around the screen much easier than before and revolutionising PC gaming by enabling precise millimetre-perfect cursor movement.