quartz watch

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A quartz watch is an electro-mechanical or fully electronic clock whose clock (as time standard ) as the clock crystal trained quartz crystal is. In addition to quartz watches with a dial or numeric display, there are also those without a display, which in computer systems usually output information about the time as an electrical signal and are referred to as real-time clocks . The movement of an electronic quartz watch is called a quartz movement . Many watch manufacturers use the spelling "Quartz" in the Anglo-Saxon language.

Early quartz alarm clock with dial display

Physical and technical background

Close-up of a tuning fork shaped watch quartz without a case

Quartz crystals are components capable of electromechanical resonance vibrations. They keep their nominal frequency within very low relative error limits (typ .: 10 −5 ≈ 1 s per day) and are therefore suitable as precise clock generators. The resonance frequency of a crystal block of a few millimeters in size, which fits easily into a standard watch case, is very high with this hard material, namely in the megahertz range. Such high frequencies are unwieldy for watches.

Due to their tuning fork design, watch crystals have been developed with a low frequency for crystals of their size as a standard frequency of 32 768 Hz, from which a second pulse can be derived by dividing the frequency by 2 15 . Fifteen T-flip-flops connected in series , each halving the frequency, are used for division. The quartz frequency is a compromise, as the current consumption of the flip-flops is proportional to the frequency, i.e. it decreases towards a lower frequency, so that the watch's battery can supply power for a long time. Furthermore, the structure is optimized for a minimum temperature coefficient in the working range of 25 ... 28 ° C, in that the frequency in this range just reaches a maximum.

The second pulse either drives a Lavet stepper motor or an electric balance oscillator in a mechanical clockwork or sets the pace for an electronic circuit . The display is made with mechanical pointers, liquid crystal screens (LCD) or light emitting diodes (LED).


Back of a wrist watch.
Below: clock quartz on the right, button cell (battery) to the left.
Above: on the right oscillator and clock divider (under black seal), on the left the coil of the Lavet stepper motor with red enameled wire for driving the hands.
Quartz movement; recognizable clockwise: the coil of the Lavet stepper motor and the quartz oscillator

The main components of a quartz watch are a clock generator based on quartz oscillations, electronics for processing the clocks and user inputs, a display part for displaying time information and, if applicable, operating states of the clock and a power supply.

Instead of a mechanical pendulum or balance wheel driven by weights or springs, the following energy sources are used:

Quartz watches - just like mechanical watches - can have various “complications” , so that wristwatches, for example, have additional hands and can display the date, chronograph , perpetual calendar , moon phase , two alarm clocks, down timer and a second time zone (24-hour display).


Quartz watch with "Twin Quartz" temperature compensation, 1979

Quartz watches with a clock quartz with the usual oscillation frequency of 32 768 (2 15 ) Hz can normally have a clock rate (progressive deviation) of ± 60 seconds per year (rate deviation: ± 2 ppm) to ± 30 seconds per month (rate deviation: ± 10 ppm) to have. Since these deviations accumulate over time, a quartz watch must occasionally be readjusted according to the time of a more precise clock or a time announcement on the radio.

Rate deviations of a quartz watch can be minimized by:

High-precision crystals and clocks (1 ... 50 ppb):

  • Pre-aging of the quartz
  • Operation in a heating furnace at constant temperature (Oven Controlled Crystal Oscillator (OCXO)). The heating furnaces are now miniaturized with volumes of less than 0.1 cm 3 to a few cm 3 .

Further measures:

  • obsolete: frequency fine adjustment by means of a trimming capacitor ,
  • Fine adjustment by means of digital calibration (inhibition compensation), the crystals vibrate a little too quickly, it is stored in a permanent memory how many vibrations z. B. to be ignored at the end of a minute.
  • temperature-compensated design, both analog (compensation circuit) and digital possible (temperature-dependent inhibition compensation)
  • Connection to radio clocks that are synchronized daily or hourly by radio (in Central Europe reception of the time transmitter DCF77 ) with the coordinated world time , or to other clocks via USB , Bluetooth or the Internet and synchronization with more precise clocks. Many portable devices synchronize themselves to the PC time when connected to the PC, PCs for their part can synchronize themselves with Internet time servers via NTP .


Technical requirements

The quartz watch was developed in connection with the high-frequency research that began during the First World War. In the 1920s, devices were created to generate and control the transmission frequencies for the rapidly increasing radio stations. Since frequency is defined as the reciprocal of the period , the technique of quartz-stabilized normal frequency generators could also be used for the construction of the first quartz watches.

Prerequisites for the development of quartz watches were:

  • the discovery of piezoelectricity by Jacques and Pierre Curie in 1880.
  • Electronic circuits for exciting the quartz and stabilizing an oscillating circuit, developed by Walter Guyton Cady in 1920 and 1921, as well as the simplification of the circuit by George W. Pierce and RL Miller in 1922. The Pierce-Miller circuit is the most widespread type to this day piezoelectric circuit.
  • Output units for the second cycle. For this purpose, frequency dividers or high-speed synchronous motors had to be developed.

The pioneering phase up to the Second World War

National frequency standard of the USA 1929, consisting of four heated crystal oscillators at Bell Laboratories

On October 13, 1927, Joseph W. Horton and Warren Alvin Marrison of Bell Laboratories in New York presented the first quartz watch at the conference of the International Union of Scientific Radio Telegraphy. A quartz oscillator with a resonance frequency of 50  kHz controlled an electronic oscillating circuit whose alternating current drove a small synchronous motor with a pointer mechanism.

A group of four further developed crystal oscillators from Bell Laboratories served as the national frequency standard of the United States in 1929, as shown in the adjacent figure. In order to minimize external temperature fluctuations and thus thermally induced fluctuations in the accuracy of the oscillator, the four quartz oscillators were kept at a constant temperature in heated cabinets. Heated quartz oscillators as quartz oven ( English Oven Controlled Crystal Oscillator OCXO hereinafter), and thanks to an ingenious method of comparison oscillators with each other, the National Bureau of Standards was the norm frequency with an accuracy of 1 × 10 -7 specify.

In 1928 General Radio from Cambridge (MA) offered a standard frequency standard that was factory-fitted with a synchronous clock. This electronic device was only used as a clock in exceptional cases, but mostly as a measuring device for scientific experiments. The dial was only rarely used as a high-precision time display, but rather as an interface for calibrating the standard frequency by comparing it with the official time signal.

In the following two decades, the quartz clock was further developed as a laboratory device. Important milestones in the definition of national standards for time and frequency were set in Germany and England. But other countries such as Italy, Japan or the Netherlands have also distinguished themselves in the further development of quartz watch technology since the 1920s.

From 1932 onwards, Adolf Scheibe and Udo Adelsberger built a number of quartz watches of different designs at the Physikalisch-Technische Reichsanstalt in Berlin. With these clocks, Scheibe and Adelsberger succeeded in demonstrating that the earth's rotation is exposed to both seasonal and short-term fluctuations . For the first time, a man-made clock was more accurate than the previous reference for time measurement, the rotation of the earth.

The quartz watches with ring-shaped quartz designed by Louis Essen at the National Physical Laboratory from 1938 onwards also set new standards. By the early 1940s, Britain had the largest network of quartz watches in the world.

The first commercially available quartz watch for industry and science was developed by the Physikalisch-Technische Entwicklungslabor Dr. Rohde and Dr. Schwarz (today: Rohde & Schwarz ) developed in Munich. The CFQ quartz watch, which skilfully circumvented the imponderables of early valve electronics with a patented combination of quartz oscillator and tuning fork, came onto the market in 1938. Due to their precision and reliability, two watches of this type were used in the German time service from October 1939. They were included in the calculation of the standard time and also served as a control device for the time signal.

Post-war quartz watches

In the period after 1945, quartz clocks replaced precision pendulum clocks across the board as the industrial and scientific standard. The best devices meanwhile achieved an accuracy of 1 · 10 −9 .

Patek Philippe Chronotome. First portable battery quartz watch produced in small series, from 1960

Efforts to miniaturize quartz watches should prove to be particularly momentous. During the Second World War, attempts had already been made at the Borg-Gibbs Laboratory in the United States and at Rohde & Schwarz in Germany to develop portable quartz watches. However, this failed due to the excessive power consumption of the tube electronics. It was not until the late 1950s that the Geneva watch manufacturer Patek Philippe succeeded in producing the first portable quartz watches thanks to semiconductor technology, innovative synchronous motors and reliable batteries. Like the battery-powered quartz watches from other watch factories ( Seiko or Junghans ), these quartz watches were significantly more expensive than high-quality mechanical watches in the 1960s.

Quartz watches for everyone

Prototype of a quartz wristwatch, model Beta 1, Center Electronique Horloger (CEH), Switzerland, 1967

Thanks to microelectronics, it was possible to build the first quartz watches for the mass market around 1970. The frequencies of the quartz oscillators were mostly below 10 kHz at this time. The price of car clocks, wall clocks and table clocks fell quickly. From the mid-1970s onwards, quartz watches were cheaper than conventional mechanical timepieces, much more accurate and largely maintenance-free, except for changing the battery.

A little later, this development began in the area of ​​wristwatches. The quartz watch for the wrist was "invented at least eight times" in Switzerland, Japan and the USA. Shortly afterwards, companies in Germany and France also presented their own designs.

Quartz wristwatches first came into the focus of the general public in 1967 through the chronometer competition at the observatory in Neuchatel, Switzerland. The Swiss research center for electronic watches "Center Electronique Horloger" (CEH) and Seiko submitted prototypes of quartz wristwatches. The quartz watches were superior to all other mechanical wristwatches. Thanks to temperature compensation, the Swiss quartz watches achieved even better values ​​than the competition from Japan.

Seiko Astron with Cal. 35A, first quartz wristwatch sold at Christmas 1969 in an edition of 100 pieces

But it should pay off for Seiko that when developing quartz wristwatches they consistently paid attention to later mass production. At Christmas 1969, Seiko in Tokyo sold the first small series of quartz wristwatches, the Astron, but still at the unit price of a small car. With their groundbreaking design for quartz movements, Seiko laid the foundation for Japanese market dominance worldwide. By 1972/73, Seiko had developed three key technologies for series production, which to this day characterize practically every quartz wristwatch with an analog time display: the tuning fork-shaped, photolithographically manufactured quartz resonator, the integrated circuit of the CMOS type and the stepping motor.

Quartz watches with digital displays usually get by without any mechanical parts. The first solid state quartz watch, the outrageously expensive Pulsar from Hamilton (USA), had red numbers with light emitting diodes (LED) in 1972. However, energy saving liquid crystal displays (LCD) were soon used.

By the mid-1970s, the price of quartz watches had already fallen below 100 DM, and it continued to fall rapidly. Mechanical movements were no longer competitive in terms of price and quality. Many traditional watch factories had to close in the quartz crisis of the 1970s and 1980s.

Around 1975 it became clear that the basic structure of the quartz wristwatch developed by Seiko would prevail. A few years later, manufacturers of clockworks also switched to this design. All later developments only concerned the further reduction of the number and size of the individual parts or additional functions:

  • In 1973 Staiger launched the CQ 2002 movement in St. Georgen (Black Forest). Thanks to a 4,194,304 (2 22 ) Hz quartz, it achieves a significantly higher level of accuracy than previous quartz movements for the end user.
  • In 1974, Omega in Switzerland built the Constellation “Megaquarz” marine chronometer, an analog quartz wristwatch whose oscillating circuit oscillates at 2,359,296 (3 2  · 2 18 ) Hz.
  • In 1976 Omega was the first manufacturer to introduce a new type of insert quartz watch, the waterproof series "Seamaster".
  • The first digital watches with pocket calculators appeared in the mid-1970s, including the HP-01 from Hewlett-Packard in 1977 , which also made it possible to calculate times / periods.
  • In 1980 Omega built the “Dinosaure”, the thinnest quartz watch (1.46 mm).
  • The first radio-controlled watch appeared in 1986 (simultaneously from Junghans from Schramberg and Kundo from St. Georgen), and in 1990 the first radio-controlled wristwatch from Junghans.
  • In 1988 the first quartz watch with automatic energy generation (AGS - Automatic Generating System), later renamed "Kinetic", was introduced by Seiko (caliber 7M22).
  • In 1998 Seiko introduced the “Ruputer”, the first wristwatch with PDA functions (“Wrist PDA”).
  • In 2005, Seiko introduced the Spring Drive as a spring-powered, quartz-controlled clockwork mechanism.
Quartz clock with time signal control (radio clock)


  • Gisbert L. Brunner : The long road to electronic precision. In: Watches - Jewels - Jewelry. Heft 2, 1995, pp. 95-104, and Heft 3, 1995, pp. 71-78.
  • Johannes Graf (ed.): The quartz revolution. 75 years of quartz watch in Germany. Lectures on the occasion of the conference in the German Watch Museum in Furtwangen on August 20 and 21, 2007, Furtwangen 2008. ISBN 3-922673-27-9 .
  • Helmut Kahlert , Richard Mühe , Gisbert L. Brunner, Christian Pfeiffer-Belli: Wristwatches: 100 years of development history. Callwey, Munich 1983; 5th edition, ibid. 1996, ISBN 3-7667-1241-1 , pp. 105-115 and 505.
  • Michael A. Lombardi: The Evolution of Time Measurement, Part 2: Quartz Clocks, in: IEEE Instrumentation & Measurement Magazine, Vol. 14, 2011, pp. 41-48.
  • Lucien F. Trueb, Günther Ramm, Peter Wenzig: The electrification of the wristwatch, Munich 2011. ISBN 978-3-87188-236-4 .

Web links

Commons : Quartz Watches  - Collection of pictures, videos and audio files
Wiktionary: Quartz watch  - explanations of meanings, word origins, synonyms, translations

Individual evidence

  1. ^ Helmut Kahlert, Richard Mühe, Gisbert L. Brunner, Christian-Pfeiffer-Belli: wrist watches: 100 years of development history. 1996, p. 505.
  2. Wolfgang Reinhold: Electronic circuit technology: Basics of analog electronics. Karl Hanser, 2nd edition 2017, p. 296
  3. Bernd Neubig, Wolfgang Briese: The large quartz cookbook. Excerpts in [1] , p. 4; PDF file accessed on April 17, 2018
  4. Michael A. Lombardi: The Evolution of Time Measurement, Part 2: Quartz Clocks, in: IEEE Instrumentation & Measurement Magazine, Vol. 14, 2011, pp. 41–48, here p. 42.
  5. ^ Joseph W. Horton, Warren A. Marrison: Precision Determination of Frequency, in: Proceedings of the Institute of Radio Engineers, Vol. 16, 1928, pp. 137-154.
  6. Michael A. Lombardi: NIST Primary Frequency Standards and the Realization of the SI Second, in: Measure, Vol. 2, No. 4, 2007, pp. 74-89, here p. 76.
  7. http://www.ietlabs.com/pdf/GR_Experimenters/1935/GenRad_Experimenter_June_1935.pdf , p. 13.
  8. Johannes Graf: Quartz watches are not made of quartz. Series quartz watches from the interwar period, in: Deutsche Gesellschaft für Chronometrie. Jahresschrift, Vol. 54, 2015, pp. 67–90.
  9. ^ Shaul Katzir: Pursuing frequency standards and control. The invention of quartz clock technologies, in: Annals of Science 2015, doi : 10.1080 / 00033790.2015.1008044 .
  10. ^ Horst Hassler: A. Scheibe and U. Adelsberger - physicists and clockmakers from Germany. (PDF; 426 kB)
  11. ^ Eduard C. Saluz: Quartz watches and precision time measurement in England and France from 1930 to 1950, in: The Quarzrevolution. 75 years of quartz watch in Germany. Edited by Johannes Graf, Furtwangen 2008, pp. 40–51, on England especially pp. 42–46.
  12. Company history: 75 years of Rohde & Schwarz
  13. Johannes Graf: Quartz watches are not made of quartz. Series quartz watches from the interwar period , in: Deutsche Gesellschaft für Chronometrie. Jahresschrift, Vol. 54, 2015, pp. 67–90, here p. 77.
  14. ^ Marvin E. Whitney: The Ship's Chronometer, Cincinnati (OH) 1985, pp. 307-310.
  15. Johannes Graf: Quartz watches are not made of quartz. Series quartz watches from the interwar period , in: Deutsche Gesellschaft für Chronometrie. Jahresschrift, Vol. 54, 2015, pp. 67–90, here pp. 83–86.
  16. Michael Schuldes: First portable, battery-operated quartz watch from the Patek Philippe company , in: The Quarzrevolution. 75 years of quartz watch in Germany. Edited by Johannes Graf, Furtwangen 2008, pp. 52–61.
  17. ^ Helmut Kahlert, Richard Mühe, Gisbert L. Brunner, Christian-Pfeiffer-Belli: wrist watches: 100 years of development history. 1996, p. 505.
  18. Lucien F. Trueb, Günther Ramm, Peter Wenzig: The electrification of the wrist watch , Munich 2011, p. 99.
  19. Trueb, p. 102.
  20. Like the following: Trueb, pp. 108–111.