By Tom Fiske
I had the privilege to chair a session at the Symposium Thursday morning on display standards and transparent displays. This session was run by the Display Measurement topical subcommittee, part of the program committee that puts together the conference. Marja Salmimaa from Nokia Technologies (Finland) was my co-chair.
It’s always satisfying when a session that you assembled back in January at the paper selection meeting really comes together at the conference in June. This one demonstrated one of the best things about the conference -- its international nature. Five countries and three continents were represented.
Michael Becker from Instrument Systems (Germany) gave the first invited paper, a very nice overview of the main emphases of the various major standards organizations concerned with displays. Why do we need standards? They fill the need for clear communication between different groups and countries by supplying precise terminology and the taxonomy that provides structure for the terminology. The CIE concerns itself with the fundamentals of photometry and colorimetry. The IEC provides data sheets and standards for display components and devices. The ISO deals with the ergonomics of human-system interaction. He covered some highlights of recent work by those organizations, including measurements for non-planar (curved) light sources and displays, OLED performance in various ambient lighting environments, transparent displays, and the characterization of speckle in optical systems. He concluded his talk by remarking on the complementary topics emphasized by each organization and how cooperation between them is good for the standards setting enterprise.
Kei Hyodo (pictured above) of Konica Minolta (Japan) is Assistant Secretary for IEC TC 110, the group that covers electronic display devices. In the second invited paper, he discussed the history and structure of the IEC TC 110 and highlighted some of the new topics that the working groups are currently engaged in, including touch, lasers, curved displays, and wearable displays. He emphasized the good working relationship with SID and the ICDM.
Xin-Li Ma from BOE (China) gave a nice talk about optical measurement methods for transparent LCDs. He focused mainly on the effect of the display on objects that are viewed behind the display. He discussed the effect on MTF, level of transparency, and color distortion.
The session finished up with a pair of talks from John Penczek and Paul Boynton from NIST (USA). They covered a general framework for characterizing transparent displays and suggested measurement techniques. These were extensions and applications of techniques found in the Reflection Measurements section of the IDMS. They emphasized that reflectance and transmittance factors can be measured and then used to predict the performance of transparent displays in a variety of lighting environments. In other words, take advantage of linear superposition and don’t try to recreate specific lighting environments in order to characterize display performance in various conditions.