From cathode ray to flat panel
Opinions differ regarding as to precisely when and where television was invented. However, what is certain is that its development (from the mid-1930s) was made possible thanks to the arrival of CRT (cathode ray tube) displays. CRT consists of an electron gun that fires electrons onto a phosphor-coated screen to produce moving images. CRT displays, first monochrome, then colour, were the unique choice for television sets, computers and other systems for nearly 60 years before being phased out relatively rapidly by FPDs.
Swift shift in IT
Compared to CRT-based TV sets, which delivered a wide range of colours, the first CRT monitors for IT equipment, which were limited by inadequate graphic cards, were monochrome and didn’t provide good or sharp pictures. Colour CRT monitors for IT equipment first appeared in the early 1980s.
FPDs were initially used in laptop computers, in the form of monochrome LCD (liquid crystal display) screens. Their limited size, weight and power consumption made them a much better choice than the CRT displays used in the first "portable" computers, which weighed well over 10 kilos. The first standalone flat panel displays for computers were introduced in the mid-1990s, but were quite expensive at the time. However, their widespread adoption followed quickly as their price dropped and as they offered many advantages over CRT monitors, including lower power consumption and a smaller footprint, major benefits in business environments where space is at a premium. From the mid-2000s, LCD screens, initially offered in the 4:3 aspect ratio, like CRT displays, became available in the wider 16:9 format.
Slower transition in television
Whilst CRT displays were replaced fairly rapidly by FPDs in IT equipment, consumers were more reluctant to adopt so-called flat-screen TVs. A 2002 document from the EBU (European Broadcasting Union) Technical Department noted that flat panel displays were just starting to make inroads into domestic TV households. "CRTs still take 99% of the market,” the report said. Yet, less than ten years later, the share of CRT TVs had dropped to 10% of worldwide shipments of sets.
The slow initial take-up rate of FPDs for TV sets was mainly due to the high prices of the first large flat TV screens, originally PDP (Plasma Display Panel), and to the protracted preparation and slow publication of international digital and HDTV (High-Definition Television) standards and the resulting lack of sufficient and suitable content in the appropriate 16:9 format.
However, the sale of FPD TV sets then picked up rapidly, driven by lower prices of LCDs and the wide range of screen sizes, extending from under 20 inches (making them ideal replacements for CRTs in low-income countries) all the way to over 40 inches (suitable for high-income markets). New international TV standards, leading to the widespread introduction of content required by multichannel (digital) households and HDTV, also helped boost the sales of the new sets.
Beyond the traditional domains of TV sets and computers, flat panel displays are used in many other areas. They have enabled the spectacular expansion of mobile telephony and the emergence of entirely new devices, such as e-readers, which use EPD (electronic paper display), a technology designed to mimic the appearance of ordinary ink on paper. New FPD technologies are constantly being developed, opening up more possibilities for existing devices and paving the way for new ones.
LED (light-emitting diode) backlighting, resulting in a better image contrast and lower consumption, has been gradually introduced into LCD displays. Different technologies using LEDs, such as OLED (organic light emitting diode display), have been developed to produce new types of FPDs for mobile phones and now TV sets. Beside multimedia and ICT, many industries such as medical, retail, automotive, aeronautics and avionics and transportation rely on displays, and FPDs in particular, to operate smoothly and effectively..
TC work central to FPD expansion
The FPD market, driven by high demand in emerging economies and an expanding range of possible applications, is expected to exceed USD 102 billion by 2015.
LCD continues to be the largest product segment in the FPD market while the more recent OLED technology, driven by applications in mobile phones and television, represents the fastest growing sector.
TC 110 prepares International Standards in the field of electronic display devices (excluding CRTs) and specific relevant components. It works on terms and definitions, letter symbols, essential ratings and characteristics, measuring methods, specifications for quality assurance and related test methods, and reliability.
It was initially established as SC (Subcommittee) 47C in 1998 under TC 47: Semiconductor devices, focusing on standards development in the area of flat panel display. It was transformed into a full TC in June 2003 when it began to encompass standardization work in OLED, 3DDD (3 dimensional display devices for 3DTV), EPD or non-volatile display devices, FDD (flexible display devices) and other emerging technologies.
To cover all devices, TC 110 established six WG (Working Groups), each one dealing with a specific area: LCD, PDP, OLED, 3DDD, EPD and FDD. TC 110 also set up project teams to prepare standards for back light units for LCD devices.
TC 110 works closely with a number of TCs, in particular TC 100: Audio, video and multimedia systems and equipment. As regulations in most countries now require reducing waste material and energy use through recycling, reuse of components and more energy-efficient appliances, it also works closely with TC 111: Environmental standardization for electrical and electronic products and systems.
Extensive and global network
The global significance and impact of TC 110 activities are illustrated by its relationship with many important international bodies. It works with subcommittees of the CISPR (International special committee on radio interference). CISPR is an organization within the IEC that was established to consider the protection of radio reception from interference. Its members include CIGRE(International Conference on Large Electric Systems), the EBU, ETSI (European Telecommunication Standards Institute), IARU (International Amateur Radio Union) and ITU-R(International Telecommunication Union, Radio Sector).
TC 110 Secretary Masao Uehara says that work to improve FPDs follows two tracks. The first is to improve FPD performance for both resolution and colour space. The second concerns the development of new technologies and improvement of existing ones.
As regards resolution, there is still scope for improvement. Japan’s public broadcaster, NHK, has developed the UHDTV (ultra HDTV) digital video format, which offers 16 times the number of pixels of HDTV. UHDTV displays, which are much larger than current HDTV screens, have been demonstrated at various professional shows such as the 2006 and 2008 IBC (International Broadcasting Convention), Amsterdam, Netherlands, or the 2009 and 2012 International CES (Consumer Electronics Show), Las Vegas, United States.
The objective is to introduce UHDTV in homes between 2016 and 2020. However, technical questions remain with regard to the availability of content and the bandwidth to transmit that content.
Uehara says that performance can also be improved in the rendering of colours and other optical aspects that still do not match the whole range of human visual acuity.
The second track of TC 110 work concerns technologies, the objectives being to improve existing ones, such as HDTV, 3DTV or touch screens, and to develop new technologies. The latter include OLED, with AMOLED (active matrix OLED) [see article in this e-tech], in particular, offering significant prospects for better TV and mobile devices displays, as well as foldable and flexible displays.
With the growing global appetite for higher quality and new functions in multimedia devices, the range of applications and demand for FPDs keep expanding. To support this expansion, TC 110, which has so far published over 30 International Standards, can expect a significant workload over coming years.