The optical mouse is a computer mouse first introduced by Microsoft on April 19, 1999, that utilizes LEDs (light-emitting diodes) or laser to help track movement. These mice are identified by examining the bottom of the mouse. As seen in the picture the optical-mechanical mouse has a ball, and the optical mouse has a light emitting from the bottom.
How does an optical mouse work?
An optical mouse also has a tiny low-resolution camera that takes a thousand or more pictures every second. In the camera, the CMOS (complementary metal-oxide semiconductor) sensor sends a signal to a DSP (digital signal processor). The DSP can analyze each picture for pattern and light changes and then based on those changes moves the mouse cursor on your screen.
Optical mouse disadvantages
Drawbacks of some optical mice include working properly in rooms with bright lights and on some surfaces such as a glass table. However, in comparison to optical-mechanical mice, optical mice are a much better solution.
Why is the mouse light red?
Although not all optical mice use red, it's the most common LED used because it's typically the cheaper diode and because the photodetectors are more sensitive to red light.
Are all optical mice wireless?
No. An optical mouse is only the technology used to detect movement and there are both wireless versions and corded versions of optical mice.
Further optical mouse history
Before Microsoft introduced their mouse in 1999, there were many different companies and inventors who had earlier styles of optical mice. In the 1980s, Richard Lyon and Steve Kirsch both independently created their own versions of an optical mouse that required a special surface to move the cursor.