The optical mouse's popularity boomed in the late 90s when it started being shipped as an extra feature to many computer systems. The optical technology became increasingly popular among users because it made working with the mouse much easier than with the traditional ball mouse. Since then finding a regular ball mouse has become somewhat of a challenge.
So how does the optical technology actually work?
The optical mouse is equipped with a light emitting diode (LED) and photodiodes which it utilizes in order to detect movement relative to a surface ie a mouse pad or a desk top.
Essentially, the mouse is equipped with an optoelectronic sensor (a small low-resolution video camera) which takes successful images of the surface on which the mouse operates. The images of the surface that the sensor takes are captured in continuous success and compared with each other to determine how far the mouse has moved.
The modern optical mice work on most surfaces. Some exceptions are glass, mirror and other specific surfaces.
The color of the light emitting diode (LED) of the optical mice is usually red simply because red diodes are inexpensive but it is not uncommon to come across blue light emitting diodes either.
Unlike ball mice optical mice do not have any moving parts which leaves almost no room for mechanical malfunctions and optical mice are less breakable.
The light emitting diode of battery-powered wireless optical mice only glows steadily when movement is detected. The rest of the time it flashes intermittently to save power.
So what's the difference between the optical mouse and the laser mouse?
Instead of using a light emitting diode the laser mouse uses an infrared laser diode. The small infrared laser the mouse is equipped with significantly increases the resolution of the image taken by the mouse. The laser enables around twenty times more surface tracking power to conventional optical mouse technology.
Glass laser mice (aka glaser mice) can also be operated on mirror or transparent surfaces.
Since the laser diode the mouse employs emits infrared light it's usually invisible for the naked eye.
So which one is better? The optical or the laser mouse?
When answering this question we should consider the dpi (dons per inch) each technology is able to track.
On the one hand, the common range for the optical mouse starts from 400 to around 800 dpi.
On the other hand, the range of the laser mouse is often above 2000 dpi. The ability of laser technology to track such high dpi makes the laser mouse much more accurate and accurate when compared to an optical mouse. That added sensitivity is why most professional graphic designers and gamers prefer the laser mouse rather than the optical mouse.
In conclusion, the laser mouse technology is arguably the better one. I say arguably because some users find the added sensitivity rather distracting while simply browsing the web or checking their email.