By Jill Friedman, Xplore Technologies
One of the biggest struggles for outdoor workers using mobile devices is being able to read their screen on days with sunshine.
The only way to avoid reflections or a display washing out is with a brighter display. Screens on tablets can be nearly impossible to read under intense sunlight, whether it’s from the sun outside or overhead lamps on the factory floor. Industrial users need to see their screen, data and visuals immediately, any downtime involved in squinting to make out a single graph could be burdensome.
Importance of NITs
A bright, sunlight-readable display also starts with having the right NITs level. NITs are the basic unit of luminance used to measure brightness. The higher the NIT count, the brighter the display.
But there’s a sweet spot of NITs for sunlight-readable displays. Standard displays on consumer tablets and mobile devices typically average around 200 to 300 NITs, and 500 NITs is considered to be sunlight readable. While some outdoor tablets range between 500 and 1,000 NITs, tablets with 1,300 NITs reach the optimal level of display brightness that make it easy to read for crews working outdoors in direct sunlight.
Such brightness is made possible by a powerful backlight. Simply put, there is no alternative to reaching this level of brightness without a solid backlight. But the strong backlight also needs balancing with other aspects, like low-light settings and energy management. For example, to counteract varied light settings, ambient light sensors built into the tablet recognize when a user is moving from a low-light setting to a high one, and adjusts the brightness accordingly.
Contrast Also Part of the Equation
While brightness makes the screen easier to read, there’s still another level to ensuring viewability: Contrast. And the brighter the screen, the great the contrast should be so users can clearly make out graphic images and data.
Contrast is measured as a ratio of the brightest color compared to the darkest black, and many mobile devices have ratios around 100:1. However, brightness-enhanced rugged tablets have a 600:1 contrast ratio, which means the brightest color is 600 times brighter than the darkest black.
Such rugged tablets with 600:1 ratios make it much easier for workers in glaring light to make out colors for bar graphs or mapping applications, data table borders and clearer images.
Enhanced LED Displays
One important note is that as the NIT count grows, the more energy is needed to power the backlight. To ensure optimum brightness and proper energy management and efficiency, LEDs are often used as the lighting source for the backlight.
Hailed for the energy-efficient qualities, LEDs can produce the brightness needed for viewing in direct sunlight without having to sacrifice anything, or consume excess amounts of energy. In fact, not only are they more efficient sources of lighting, but longer lasting, more reliable and less costly than conventional lighting sources. The wealth of positive attributes make LEDs the best choice for rugged tablets, and users will notice the benefits of them.
The tablet screen is always being looked at by industrial users, but is less so understood for all its complexities and elements. NITs may be a foreign concept and some might have no frame of reference for a good contrast ratio or energy savings, but these elements are crucial to sunlight-readable display. It’s all about balance – balancing higher brightness with better thermal management – and the combination of more NITs, better contrast and heightened energy savings create a formidable tablet display.