Rugged smartphone brand Kyocera has been working on the technology for a while. Last year, it demonstrated a prototype display at MWC and returned to the show this week to reveal its progress in bringing a working design to market. The company told Gizmag that it is now much closer to commercialising the technology, hinting it could be used in actual phones in the relatively near future.
The screen works by adding a very thin layer of solar cells between the glass and the touchscreen layer beneath. The display looks no different than a usual smartphone’s but is able to effectively power itself, leading to minimal drain of the phone’s battery and the possibility of increasing charge when in standby mode.
The current prototype is able to provide 1 minute of talk time after three minutes exposure to direct sunlight. It’s certainly not the fastest charging system around but then it is all based on a 0.55 mm-thick pane of solar cells from French photovoltaic surface supplier SunPartner.
The two companies have worked together to improve the performance of the concept. The display is now 8x more efficient than it was at MWC last year. It is also much brighter as Kyocera and SunPartner have found the right balance between visibility and efficiency. A darker display increases the efficiency of the solar cells but inevitably makes the screen harder to use.
Kyocera doesn’t consider the technology ready for consumer use yet. The charging rate is still far too slow to be a feasible alternative to a wall outlet alternative, making it useless for most people.
However, there are a few areas in which the display could immediately prove its worth. Kyocera sees it being most helpful to people who will be outdoors or away from a power source for extended periods of time, particularly if they might not be using their phone much while away.
The phone may charge at an agonizingly slow rate but the current prototype supplies enough power to at least keep the phone alive in standby mode and at best gradually store power in the battery. In an emergency situation, such as in the case of a hiker lost or injured in a remote region, this could be an invaluable feature, enabling repeated calls to relief workers without worrying about the phone switching off.
For now, the display remains in development with no defined timeframe for getting it installed in a consumer device. Kyocera and SunPartner will continue to experiment with the prototype though, improving its efficiency and increasing charging speed to create a more versatile implementation.
