Have you heard of optical imaging? This relatively new type of touchscreen technology involves the use of multiple sensors and lights to identify touch. The sensors are placed on the edges of the display and the lights are placed in front of a camera. When a user touches the display, his or her hand obstructs part of the light, thus allowing the sensors to identify the user’s point of touch. While optical imaging is still relatively new, it’s gaining momentum in the touchscreen market. So, what advantages and disadvantages does it offer?
Optical Imaging Pros
Unlike capacitive touchscreen devices — the most common type — optical imaging devices work with a bare finger or gloved finger. This is because they don’t rely on capacitance changes to identify touch. With capacitive devices, only a bare finger or capacitive stylus will work. But this isn’t a problem with optical imaging due to the technology’s lack of reliance on capacitance.
Optical imaging touchscreen devices also have a fast response time. With other touchscreen technologies, the device’s computer must register the touch. This process is done by the sensors with optical imaging technology, resulting in a faster response time.
Finally, optical imaging is highly accurate. When a touch a specific area on the device, it will register the touch in that area. Of course, other touchscreen technologies are also accurate, so this isn’t necessarily a selling point.
Optical Imaging Cons
A key disadvantage of optical imaging touchscreen is the fact that they don’t support multi-touch function. Multi-touch has become a common feature found in touchscreen devices, as it increases the number of control/comment options while providing users with a higher level of versatility. Pinch to zoom, for example, is a multi-touch command that’s commonly used on smartphones, tablets and other touchscreen devices. Unfortunately, optical imaging doesn’t support multi-touch commands.
Another issue with optical imaging touchscreen devices is the potential for blind spots. If the sensors or lights don’t cover the entire display, those areas won’t register a touch. Depending on the specific application, the presence of these blind spots could hinder the device’s functionality
There are both pros and cons to using optical imaging touchscreen technology. However, it’s important to note that the technology is still new, so manufacturers are still working to perfect it. Perhaps in a few years it will become an industry standard like capacitive and resistive. Until that happens, though, capacitive and resistive will likely remain the most popular touchscreen technologies.