Mechanical keyboards have been around for quite some time now. With certain iterations of mechanical keyboards, we are greeted with new switches targeted a particular niche audience. Enter, the ‘optical switch’ (pun intended) – a new switch type that retains the mechanical nature of the keys, but harnesses the speed of light to make it more responsive.
According to LYRTech, The main thing to note here is that optical switches are still very much mechanical. For the most part, they have similar construction with a keycap pushing on a stem, and a spring to reset the switch to its initial state. They can also have the same characteristics of linear actuation, tactile, or clicky. The primary difference lies in the way keystrokes are registered. Traditional mechanical keyboards rely on metal contact points, connected to the PCB of the keyboard to register keystrokes. In contrast, optical switches use lasers (usually infrared) to determine when a key is pressed. As a direct consequence, these switches do not need any soldering and can be replaced at any time.
The infancy of this seemingly space-age technology is why we do not have a wide variety of choices, unlike traditional switches. The two popular ones in the market are ‘Lightstrike’ switches or ‘LK’ switches and ‘Flaretech’ switches with ‘Gateron’ slowly coming to the scene.
1 – LK Switches
These switches rely on a traditional mechanical shaft that blocks a beam of infrared (IR) laser. When the key is pressed down, the shaft does not block the IR laser anymore, and a sensor receives the beam on the opposite side. This registers as a keypress. This allows for faster actuation and a faster reset, thereby increasing the overall responsiveness. From an engineering standpoint, LK switches are fairly easy to design and fabricate, which does not place a significant price premium on this new technology.
2 – Flaretech Switches
Flaretech switches have a more complex and rather expensive implementation when compared to their LK counterparts. They have a bottom mounted IR sensor firing upwards towards the stem of the key. As the key is pushed, the stem moves closer to IR sensor, which is then detected as a keypress. However, this arrangement gives an added functionality to the keys. The IR sensor has to ability to detect the distance the key has been pushed down, enabling ‘analog’ control of the keys, as opposed to the standard ‘ON’ or ‘OFF’ states of the keys. To cite a simple example, the acceleration of a car in-game can be controlled in stages based on how far the key has been pushed down.
As of now, there are only a handful of manufacturers offering an optical skew in their range of keyboards. This is majorly due to the newness of this technology and its subsequent lack of popularity. However, features like quicker response time, less wear and tear due to there being no metal contacts, and granular input control are well on their way to revolutionize the way we interact with our keyboards!