A Personal View – May 2014

An advert that I received last week encapsulates the progress that has been made with TVs over the past ten years. But I expect even more dramatic advances in the following decade. Hold onto your seats as technology takes off and rockets into the sky of our imagination.

The TV industry is currently in the throes of a revolution which I provide the appellation the 5th iteration which comes hard on the heels of the 4th which was the discarding of the cumbersome CRT and its replacement with the flat screen high definition screens. My crystal ball only conjures up this imminent revolution and then one more. For reasons to be explained and which will become self-evident, nothing is possible subsequent to that. The TV set as we know it will no longer exist in its current form.

But before we consider what the future holds, let us take a glance backwards from where we have come: the history of this revolutionary entertainment machine. What is hugely difficult to comprehend is that is just over half a century ago, the sales of TV sets were miniscule. From the 1960s it has mushroomed to the point where most houses have almost one set per person.

In my mind John Logie Baird is remembered as the father of television but in reality, like most inventions, a whole string of inventors were involved, each with their own decisive part to play in its conception in completing the jig-saw puzzle that is today’s TV set.

Electromechanical television

The beginnings of mechanical television can be traced back to the discovery of the photoconductivity of the element selenium by Willoughby Smith in 1873 and the invention of a Nipkow scanning disk by Paul Gottlieb Nipkow in 1884.

Finally in 1926 John Logie Baird, a Briton demonstrated televised moving images.  On the left is the first known moving television picture as produced by John Logie Baird.

With his so-called Nipkow disc, German technician Paul Nipkow is regarded as the inventor of the TV set. During television’s electromechanical era, commercially made television sets were sold from 1928 to 1934 whereas Baird’s Televisor sold from 1930 to 1933 and is considered as the first mass-produced set, selling about a thousand units. The typical chicken-and-egg situation prevailed where demand for the physical set was suppressed due to lack of content but overshadowing all of that was the abysmal quality of the pictures. All aspects of the end to end chain conspired to ensure its non-viability.

Electronic television

From this hesitant and uninspiring start, the TV set moved into its second phase, the electronic television set. Would this chapter in its development prove to be more successful or would it require additional innovations.

In 1908 Alan Archibald Campbell-Swinton published a letter in a scientific journal in which he described how “distant electric vision” could be achieved by using a cathode ray tube, the first iteration of the electronic television method that would dominate the field until recently.

Campbell-Swinton also announced the results of some “not very successful experiments” he had conducted with Minchin and Stanton in which they had attempted to generate an electrical signal by projecting an image onto a selenium-coated metal plate that was simultaneously scanned by a cathode ray beam. By the late 1920s, when electromechanical television was still being introduced, several inventors were already working separately on versions of all-electronic transmitting tubes.

On September 7, 1927, Farnsworth’s image dissector camera tube transmitted its first image, a simple straight line, at his laboratory in San Francisco. In 1929, the system was further improved by elimination of a motor generator, so that his television system now had no mechanical parts. That year, Farnsworth transmitted the first live human images with his system.

Meanwhile, Vladimir Zworykin was also experimenting with the cathode ray tube to create and show images. While working for Westinghouse Electric in 1923, he began to develop an electronic camera tube. But in a 1925 demonstration, the image was dim, had low contrast and poor definition, and was stationary. In 1928 Zworykin received a patent for a colour transmission version of his 1923 patent application.

The problem of low sensitivity to light resulting in low electrical output from transmitting or “camera” tubes would be solved with the introduction of charge-storage technology by Kálmán Tihanyi beginning in 1924. His solution was a camera tube that accumulated and stored electrical charges (“photoelectrons”) within the tube throughout each scanning cycle. Charge storage remains a basic principle in the design of imaging devices for television to the present day.

Philo Farnsworth gave the world’s first public demonstration of an all-electronic television system, using a live camera in Philadelphia during August 1934. In 1933 RCA introduced an improved camera tube that relied on Tihanyi’s charge storage principle. The new tube had a light sensitivity of about 75,000 lux, and thus was claimed to be much more sensitive than Farnsworth’s image dissector.

In Britain the EMI engineering team in 1932 applied for a patent for a new device they dubbed “the Emitron”.  Finally the super-Emitron was between ten and fifteen times more sensitive than the original Emitron and iconoscope tubes and, in some cases, this ratio was considerably greater. It was used for an outside broadcast by the BBC, for the first time, on Armistice Day 1937, when the general public could watch in a television set how the King laid a wreath at the Cenotaph. This was the first time that anyone could broadcast a live street scene from cameras installed on the roof of neighbouring buildings, because neither Farnsworth nor RCA could do the same before the 1939 New York World’s Fair. Whereas we now take outside broadcast as a commonplace occurrence, these first such broadcasts were only made immediately prior to WW2.

In 1941, the United States implemented 525-line television whereas in Europe the world’s first 625-line television standard was designed and subsequently implemented as the CCIR standard.

The first commercially made electronic television sets with cathode ray tubes were manufactured by Telefunken in Germany in 1934, followed by other makers in France, Britain, and America in 1938. The cheapest of the pre-World War II factory-made American sets, a 1938 image-only model with a 3-inch (8 cm) screen, cost US$125, the equivalent of US$2,020 in 2013. The cheapest model with a 12-inch (30 cm) screen was $445 ($7,200).

An estimated 19,000 electronic television sets were manufactured in Britain, and about 1,600 in Germany, before World War II. About 7,000–8,000 electronic sets were made in the U.S. before the War Production Board halted manufacture in April 1942, production resuming in August 1945.

Colour television

In television initial development, all the focus had been on B&W – black and white but in parallel with the continued development of B&W.

In its most basic form, a colour broadcast can be created by broadcasting three monochrome images, one each in the three colours of red, green and blue (RGB). When displayed together or in rapid succession, these images will blend together to produce a full colour image as seen by the viewer.

One of the great technical challenges of introducing colour broadcast television was the desire to conserve bandwidth. It consumed  potentially three times the bandwidth of the existing black-and-white standard sets, and not use an excessive amount of radio spectrum. Sounds familiar doesn’t it.

Although all-electronic colour was introduced in the U.S. in 1953, high prices and the scarcity of colour programming greatly slowed its acceptance in the marketplace. The first national colour broadcast in January 1954, but during the following ten years most network broadcasts, and nearly all local programming, continued to be in black-and-white. It was not until the mid-1960s that colour sets started selling in large numbers, due in part to the colour transition of 1965 in which it was announced that over half of all network prime-time programming would be broadcast in colour that autumn. The first all-colour prime-time season came just one year later.

Colour broadcasting in Europe was not standardized on the PAL format until the 1960s, and broadcasts did not start until 1967. By this point many of the technical problems in the early sets had been worked out, and the spread of colour sets in Europe was fairly rapid.

The first national live television broadcast in the U.S. took place on September 4, 1951 when President Harry Truman’s speech at the Japanese Peace Treaty Conference in San Francisco was transmitted.

Different technical standards

For many years different countries used different technical standards. France initially adopted the German 441-line standard but later upgraded to 819 lines, which gave the highest picture definition of any analogue TV system, approximately double the resolution of the British 405-line system. However this is not without a cost, in that the cameras need to produce four times the pixel rate (thus quadrupling the bandwidth), from pixels one-quarter the size, reducing the sensitivity by an equal amount.

With advent of colour television most Western European countries adopted PAL standard. France, Soviet Union and most Eastern European countries adopted SECAM. In North America the original NTSC 525-line standard was augmented to include colour transmission with slight slowing down of frame rate.

Throughout the 1960s, television sets used exclusively vacuum tube electronics. This resulted in relatively heavy and unreliable TVs. In addition, vacuum tubes were poorly suited to colour television, as it required a large amount of tubes which caused further reliability problems. Because vacuum tubes only allowed for very simple NTSC/PAL filtering, the picture quality of early colour sets was rather poor.

By the early 1970s, solid-state electronics appeared and quickly displaced vacuum tubes in colour TVs (black and white sets generally continued to be tube-based). This allowed for significantly more reliable TVs and better picture quality. 1971 was the first year that sales of colour TVs in the US exceeded B&W ones. In other countries, colour was slower to arrive and did not become common in Western Europe until the 1980s.

Non-CRT Flat screen televisions

CRT technology is final defunct, deceased, no more. Not a single model can be found in a storeroom anywhere anymore. Its nemesis was the liquid-crystal-display televisions (LCD TV). These are television sets that use LCD display technology to produce images. Being thinner and lighter than cathode ray tube (CRTs) of similar display size, this potentially allowed for the manufacture of larger display panels. In spite of initial manufacturing mishaps and sky-high reject rates, manufacturers persisted in the introduction of substantially larger sizes. When manufacturing costs fell, this combination of features made LCDs practical as the standard format.

In 2007, LCD televisions surpassed sales of CRT-based televisions worldwide for the first time, and their sales figures relative to other technologies are accelerating. LCD TVs quickly displaced the only major competitors in the large-screen market, the plasma display panel and rear-projection television. LCDs are, by far, the most widely produced and sold television display type. With the revolutionary train well on its way, the various disadvantages of LCDs had to be addressed. Currently my personal bet is that LED or its next reincarnation organic light-emitting diodes (OLED) will become the dominant technology. My personal 47inch LED has superb colour rendition a together with blended colours which appears to reduce pixilation. From the dealerships anecdotally it appears that LED is finally overtaking LCD as the preferred technology.

High Definition TV

The current phase is well and truly related to the quantum of the pixels that are displayed. After high resolution cameras became the norm even on such items as cell phones, the television set was forced to keep pace. Three parameters are identified with HDTV broadcast systems viz:

• Frame size in pixels is defined as      number of horizontal pixels × number of vertical pixels, for example 1280      × 720 or 1920 × 1080. Often the number of horizontal pixels is implied      from context and is omitted, as in the case of 720p and 1080p.
• Scanning system is identified with      the letter p for progressive scanning or i for interlaced scanning.
• Frame rate is identified as number      of video frames per second. For interlaced systems the number of frames per second should be specified, but it is not uncommon to see the field      rate incorrectly used instead.

 

Current Television resolutions

The Resolution relates to the number of lines of picture that appear on the screen.

• Standard-definition television (SDTV):
  • 480i       (NTSC       standard uses an analogue system of 486i split into two interlaced fields of 243 lines)
  • 576i       (PAL,       720 × 576 split into two interlaced fields of 288 lines)
• Enhanced-definition television (EDTV):
  • 480p       (720 × 480 progressive scan)
  • 576p       (720 × 576 progressive scan)
• High-definition television (HDTV):
  • 720p       (1280 × 720 progressive scan)
  • 1080i       (1920 × 1080 split into two interlaced fields of 540 lines)
  • 1080p       (1920 × 1080 progressive scan)

 

Here there is a fundamental distinction between i [interlaced] and p [progressive] which greatly determines the picture quality. Let us compare a HDTV set using 1080p of which our household has three and our original PAL TV set of some 10 years ago. As the resolution of the PAL set was a meagre 576i, there were only 288 unique lines on the screen as opposed to my LED HDTV sets with 1080 unique lines of picture. That is almost a factor of four and is why the clarity of the picture is vastly superior to the old PAL system.

The Future

Ultimately we arrive at the future part of which is already started to be with us. Firstly the resolution: Again the TV manufacturers propose increasing it by a factor of four. Provisionally this was given the sobriquets of 4k, 8k & 16k but the marketing people have clearly overridden the technicians and called it UHD TV – Ultra High Definition Television.

 

Ultra-high-definition television (UHDTV) resolutions:

• 2160p (3840 × 2160 progressive scan) – 4k
• 4320p (7680 × 4320 progressive scan) – 8k
• 8640p (15360 × 8640 progressive scan) – 16k

The 4k variant is already available locally but at phenomenal cost. For instance the 85inch Samsung UHD set currently retails for R 385,000. A 65inch set has been introduced retailing for R 90,000. The quality of the picture is astonishing. Even standing two to three inches away from the screen, one is unable to detect individual pixels at all.

Apart from the current price, there is the usually chicken-and-egg scenario. Until TV prices are reduced significantly to stimulate demand, no content will be produced to play on it. Sony has recognised this fatal flaw and has committed itself to commissioning some movies using this standard. But the problem is more intractable than that. Currently there are no DVD players that can play UHD let alone a standard for what the player should be produced to. Like all breakthrough technologies, this scenario plays itself out every time and like on the other occasions, the various technology threads will ultimately get into sync again but all of this will take time.

Now the TV producers have started producing TV sets with curved screens. The whole logic of high pixel ratios and curved screens is counterintuitive unless one has looked at a UHD screen. Previously the accepted logic was to sit as far away from the screen as possible so as not to be able to observe the individual pixels. With this no longer being a consideration, the TV logic becomes aligned to that of cinema logic: Sit as close as possible to a large screen and become immersed in the experience.

No sets using 8k or 16k logic have yet been produced and one wonders given one’s inability to view individual pixels at the 4k level, why additional pixels need to be displayed?

The final revolution

The next innovation will be the introduction of sets that will cater for another sense; our olfactory glands. The use of smells will introduce another layer of realism to one’s TV. Imagine the odour of a field after a shower of rain or the stench of a rotting body to enhance the experience.

Like all revolutions, this will come in phases with olfactory realism preceding the final phase. The final version of the TV set will be a much more dramatic advance as it will address all the senses simultaneously: sight, sound, smell, taste and feel.

How is that possible?

Easy.

One will sit back on the couch, close one eyes tightly, block one’s ears with cotton wool and plug the TV cable into one’s brain.

One will experience the full repertoire of senses in real time and with total clarity without the need for huge screens.

The truly immersive experience that Hollywood had always been striving for will finally be available.