Tablets’ High Performance Sends Them Off to Work

by Russel A. Martin

In the past few years, the emergence of tablets has driven yet another spurt of growth in the display industry and in its range of products.  At this point, roughly one quarter of the U.S. population owns a tablet, e-Reader, or related product.   The dominant use of these products is by consumers accessing information: reading books, viewing photographs, reviewing documents, checking e-mail, and inspecting Web sites.  But success in the consumer world has driven adoption of tablets in a range of other areas, including educational, industrial, military, and medical.  The viewing-heavy focus of tablets makes the display the critical element of the system.  We see this in the display-forward marketing of tablets in which resolution, color gamut, and diagonal size dominate product feature lists.  Can you think of a tablet marketed for its processor speed or configuration?

In this issue of Information Display, there are two articles that discuss tablet performance.  Ray Soneira leads us through a range of quantitative measures of display performance and careful comparisons.  He has judiciously picked four representative tablet displays to compare in detail, with LCD and OLED technologies both represented.  More importantly, he discusses the tradeoffs, compromises, and missteps in the design of tablet (and phone) displays.  Significantly, he demonstrates how strongly performance is controlled by ambient lighting.  The extra mobility afforded by tablets makes this a significant issue in a way similar to that for mobile phones.

Aldo Badano shows us what is important when one applies tablets to the medical world.  (I do not want an operation to remove a bad pixel from my kidney.)  He compares the performance of handheld displays to those of medical workstations, showing us when the mobile device can play a similar diagnostic role.  Using an analysis of gray scale, resolution, spatial noise, and ambient reflections, he compares device performance.  Not surprisingly, he finds problems with reflections similar to those pointed out by Soneira.  While the tasks done on tablets in a medical setting are different from those in the commercial or consumer space, in the end, the image-quality requirements are set by the limits of human vision.  Doctors, artists, engineers, and students all look at tablets with two eyes and need to pick out the critical details.

My expectation is that the variety and uses of tablets will expand well beyond their current focus in the consumer space.  When access to information is the primary goal of an information appliance, then tablets are the natural choice.  Data entry is not as easy as on a computer with keyboard and mouse, but for many operations, the difficulties can be overcome with well-designed user interfaces.  Outside of general consumer use, there are varying requirements for tablet displays and tablet design.  As Badano explains, uniformity and color consistency are requirements for medical applications.  In hospital settings, a mechanical design that allows easy wipe-down for sterilization would be an advantage, as might an anti-microbial screen surface.  In industrial settings, durability and an easy way to grip the tablet are strong design considerations.  For the military, sunlight readability would be a valuable feature.  If that readability came from a reflective display, then a smaller battery could be used.  That might ease some of the soldier’s burden of lugging around 7 kg of batteries.  Education faces yet another set of challenges, cost being the primary concern, but closely followed by the need for robustness in constant use.

Enjoy Soneira and Badano’s articles on tablet display performance.  Afterwards, think about how tablets are finding their way into more and more applications.  What requirements will they need to meet to succeed in the next application? •