INSIDE AN OPTICAL MOUSE

How these computer companions move a cursor on the screen.

Scroll wheel This rolling wheel is connected to a switch mechanism that tracks the direction of movement and how much the wheel has rotated.

Microswitches Two switches either side of the scroll wheel register when you click the mouse’s right and left buttons.

Cable The digital signals generated by the chip are sent via the cable – or by Bluetooth for wireless versions – to the computer to move the cursor.

Light-detector chip This chip measures the light reflected back from the desk and converts the movements into signals that are sent to the computer to move the cursor.

Light An LED bulb produces the red light which is used to track the movement of the mouse using a detection chip.