Ready for some culture? Twelve minutes of video to understand how an optical mouse works.

On several occasions, we've mentioned the remarkable footage published by the Branch Education YouTube channel. For just over seven years now, the channel's promoters have been going to great lengths to provide us with quality content designed to take us back to the workings of all the electronic/computer devices around us. From the operation of a CPU ( Central Processing Unit) to that of a GPU ( Graphics Processing Unit), via a detailed presentation of the lithographic etching process, the videos created by Branch Education are all absolutely remarkable.

In today's sequence, the Youtube channel takes a look at a peripheral that is as indispensable as it is little-known: the mouse. Alongside the keyboard, it remains - more than sixty years after its invention - one of the main communication accessories between user and computer. However, the internal design of mice has largely changed over time, and in the 90s, traditional ball mice gave way to optical mice. Laser models didn't last - too expensive with no real gain - and today, absolutely all mice rely on an optical sensor to determine the position and movements of the pointer on the screen.

This sensor, also known as an IAS (for Image Acquisition System), is associated with an LED whose sole task is to generate infrared light, which is then deflected by a lens to illuminate the mouse's sliding surface at a slight angle. This angle gives the sensor better "visibility", and the crevices of the sliding surface do the rest. These two elements are there to enable the sensor to "see" where the mouse is moving and to determine its movement vectors. The sensor takes over 17,000 photos per second! It doesn't record them, but simply compares the displacement between one image and the next: a time lag of just 59 μs, allowing it to see in which direction and at what speed the mouse has moved.

The sensor then "only" has to translate this information into pointer movements on the screen, but to understand everything in detail and with graphic elements, it's best to consult the video on the Branch Education channel. A model of its kind.

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