Rugged touchscreen tech for low-power LCD displays

Display Technology supplied two customised touch screen designs for L.B. Foster at its UK manufacturing facility. Both totem and wall-mounted units are 43 inches in size and are required to work indoors and outdoors, in often unattended locations. To meet this requirement, the TFT LCD displays supplied feature a wide operating temperature with low power consumption while offering high brightness. Each has Zytronic’s ZXY500 multitouch controller to provide millisecond fast, all-weather performance.

The touch sensors are made from printed 6-millimetre thermally tempered glass with a laminated rear hard-coated polyester film, delivering optimum impact resistance and anti-spalling in the event of breakage. The glass selected has an antiglare etched finish for better image display visibility in direct sunlight and the touchscreens also incorporate UV blocking and IR reducing filters to help protect the underlying LCD from sunlight damage and assist the overall system thermal management.

The totem and wall-mounted touchscreen units provide an unsurpassed interactive user experience irrespective of the environment and remain unaffected by rain, dirt, scratches, or extreme temperatures and work even when the user is wearing gloves.

L.B. Foster’s new INFORM02 touch screen mobile totem is designed to go through standard doorways. It is capable of running for 24 hours on a single charge from its built-in batteries with wireless connectivity to allow operators to manage content in real-time. There is also the facility for operators to locate their assets and check battery power status remotely, and an NFC optional upgrade allows users to take away information on their smartphones. As well as being dust-tight, water-resistant (meeting IP65 standards) and fire-resistant, the units are also certified to blast test ASIAD 2017 PBIED – crucial for installations at airports and other busy public venues.

The INFORM02 totem also benefits from a Litemax 43” 1800 nit High Brightness TFT, which draws a low 106W power consumption, essential to maintaining the INFORM02 24hr daily battery lifecycle. When combined with the use of a digital light sensor and controller card, this regulates brightness and power consumption within the totems in all different lighting conditions. The TFT also supports a wide operating temperature of −20 to +60°C with LCD Blacking Defect Free (Hi-Tni 110°C) Technology making it ideal for maintaining visibility in demanding environments. The updated Litemax LCD Module kit by Display Technology further enhances the performance of INFORM02, improving the passenger experience.

“Zytronic’s ability to manufacture these large-format touch sensors is ideal for our low volume, yet bespoke design requirements,” says Dagan Bradbury, Head of Visual Comms & Structures, TEW Engineering, L.B. Foster Europe. “The anti-spall polyester film laminated to the rear of the touch sensor also means that in the unlikely event that the tempered screen is broken it safely holds the small cubes of glass together and continues to protect the underlying display. To date, Zytronic has supplied several hundred touch sensors for our mobile totems and wall-mounted units.”

Creating a passenger information terminal that is accessible to all members of the public was key. Therefore, L.B. Foster’s INFORM software has a ‘flip’ function so that the interactive element of the user interface is accessible from a height of 1.4 metres. The graphical user interface software also includes 'signing' for customers with hearing impairments. In the future, there are plans to further modify the design of the touchscreens to enable attachment speakers onto the back of the glass to improve accessibility for partially sighted users and possibly to include ZyBrid hover that allows a contactless sensing option that can detect users up to 30 millimetres away from the glass surface.