The 'pretty neat idea' (as someone once described it) of a digital watch lies in the inclusion of both electricity and quartz movement in the creation of timepieces during the 1950s and '60s. This is how these innovations led to wrist-worn chronometers displaying figures instead of dials.
The Electric Watch
The Hamilton Electric Watch
In 1957, The Hamilton Watch Co of Lancaster, Pennsylvania, produced the world's first electric watch. The Hamilton Electric Watch kept time with a traditional balance-wheel mechanism which had been used in timepieces for hundreds of years and was therefore no more accurate than any other watch. However, instead of the mainspring powering the mechanism, a battery was used to power the mechanism so the need to wind was eliminated.
Although people loved the fact that they no longer had to wind the watch, it would stop when the electric contacts became worn - which happened not long into the watch's lifespan. It was a headache that the Hamilton repair department continually faced until the watch was updated in 1961.
Accutron by Bulova
At around this time, Bulova provided the next big advance in electric timepieces with its Accutron watch in 1960. This came in the form of a U-shaped piece of nickel alloy which vibrated in response to the electric current from the battery. These vibrations were of a higher frequency than the traditional fly wheel, so for the first time electricity transgressed being merely a neat idea that powers watches by also offering greater accuracy. The Accutron also did away with electrical contacts by introducing transistors, giving the watch a longer working life without wearing out. This watch was also closely tied to the US space programme being used on the Mercury and Apollo spacecraft as NASA aimed for the moon.
Refining the Quartz Movement
However, Bulova's success scared the Swiss watchmakers, who saw a potential challenge to their dominance of the best quality timepieces. They grouped together to finance a research lab the CEH (Centre Electronique Horloger). The CEH targeted their search on finding an even more accurate oscillator than the nickel horseshoe.
Quartz movements had first been used in clocks in the 1930s; by the early '60s they were even being used in marine chronometers (though admittedly with unpredictable accuracy). The CEH set about improving the accuracy and by the mid-'60s Longines and Bernard Golay had created a pocket watch that was accurate to within 0.01 seconds a day.
In 1967, the CEH produced the first wristwatch quartz movement. Due to advances in microelectronics, integrated circuitry had advanced to allow much less energy to be used, allowing for miniaturisation so that a quartz movement could fit into a wristwatch. However, the Swiss manufacturers continued to refine their mechanical techniques and soon caught up with Bulova by traditional means. After years of research, the Swiss viewed quartz as a fad that would pass, reckoning erroneously that their mechanical excellence would see them survive as kings of the heap; it was poor judgement that would eventually lead to the demise of some companies.
While the Europeans were playing one-upmanship with their various techniques, Seiko was simultaneously taking a fresh look at quartz and so it was the Japanese company who unveiled the world's first quartz wristwatch - the 35SQ Astron Watch - in Tokyo on 25 December 1969. It was expensive, costing 450,000 yen ($1,250 at the 1969 exchange rate). It had a plain face, was chunky (unlike the slimline Swiss mechanical watches) and also suffered so many technical difficulties that Seiko ended up recalling it after only producing just 100 watches.
However, although it was an apparent failure, it also marked a new stage in watch technology from which we have never looked back. Quartz technology was the new way forward in the 1970s; many Japanese watchmakers followed Seiko's lead, so too did the Americans, until eventually even the Swiss climbed on board - although not until some other manufacturers had collapsed. This competition led to slimmer, more accurate, less power-hungry watches. Even with the addition of more features as the '70s progressed, the next leap was just around the corner.
The Digital Display
Pulsar and the LED Display
In 1972, Hamilton produced the first watch with a digital display. They had hinted that they had a new breakthrough as early as 1970 but had two years of teething problems before its 18-carat gold Pulsar hit the world at a price of $2,100. By pressing a button on the side, the time was displayed on a red numeric display, caused by a light emitting diode (LED) display. Hamilton had provided a brief glimpse into the future in Stanley Kubrick's 1968 film 2001: A Space Odyssey when the company provided the futuristic digital clock that featured in the film. John Bergey who was head of Hamilton's Pulsar division said that this had inspired his team with the vision for their new timepiece which was then in development.
The LED is created by passing a electric charge through inorganic materials. Seven electronic switches went into making each of the numerals on the display. The original red light was generated by using aluminium gallium arsenide (AlGaAs), however Pulsar later produced a green LED using gallium nitride (GaN).
Many in the industry began to believe that the new quartz analogue watches would even be doomed to extinction so soon after their arrival that it wasn't worth buying into the trend, something which was reflected in the writings of Douglas Adams and other contemporary writers at the end of the 1970s and start of the 1980s.
Before the watch companies could 'do away with' the analogue watch though, they first had to bring down the price of the digital successor. Competition in the digital field increased and by 1975 there were over 80 varieties available. This competition helped to bring prices down but the product was still out of the range of the average consumer.
The Plastic Case
Texas Instruments brought the digital watch to the masses much as Henry Ford had brought the car. In 1975 they produced the first LED watch with a retail price of only $20; the following year this was halved. This level of competition saw Pulsar lose $6 million and find itself sold to competitors twice in the space of a year, eventually becoming a subsidiary of Seiko and reverting to making analogue quartz watches.
The Liquid Crystal Display
Digital watches even in the late 1970s still necessitated two hands - one to wear the watch and the other to press the button to turn on the LED display. The reason for this was that LED used up a high amount of the available power from the small power cell that could be fitted into the casing. The next innovation in digital watches would free up one hand for time keeping in a way not seen since the wristwatch replaced the pocketwatch.
Liquid Crystal Display first became possible in 1972 with the invention of the Twisted Nematic Liquid Crystal Display (TNLCD), following decades of research into liquid crystals at Hull University. It allowed a lower power level to reflect light onto a passive screen. However, this first breakthrough proved impractical due to the lack of photochemically and chemically stable nematic materials in existence in liquid-crystal form at room temperature1. A year later this problem was overcome when scientists discovered that a crystal known as cyano-biphenyl, could be made to change from one form to another near room temperature; these then were used in LCDs. They were first used in calculators in 1972 but the displays were still too big for watches.
However, by 1973 Seiko yet again led the way, this time with the first watch to utilise LCD technology. It had a six figure display. As LCD used less power than LED, the display was permanent, thus allowing for the addition of seconds to the display.
The Swiss finally embraced quartz technology but left the digital field to the Japanese and Americans settling instead to make elegant analogue quartz watches.
The Development of Digital Watches
The 1980s saw further developments in the digital watch. Already they could have stopwatches and date display, but the Japanese were already looking for further utilisation of technology.
It's hard to believe, but as far back as 1982 Seiko produced a wristwatch with a tiny TV screen. In the same year Casio produced one with a thermometer and another which could translate 1,500 Japanese words into English. Technology was coming on leaps and bounds and if it could be miniaturised enough the Japanese were putting it into a digital watch. In 1987, Casio produced a watch that could dial your phone number and Citizen unveiled one that would react to your voice.
The 1990s saw a refinement to solar-powered digital watches. Although some were produced in the 1970s, the new refinements allowed for more efficient use of energy. The meant that they could generate more power for longer periods of time. 1995 saw Timex release a Data link watch which allowed the wearer to download information from a computer to their wrist.
Surely it won't be long until we have a mobile phone/watch combination on our wrists. Taking palmtop computers and PDAs one step further and smaller may eventually see these also wearable as a watch. From the first appearance of a digital time displayed on the wrist in 1972, the technology has already advanced a great deal, so who knows where the future will take it. Looking back, it will only be limited by the imaginations of the people who design them as many obstacles have already been overcome and many more will follow.
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