Watch

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A watch is a portable timepiece intended to be carried or worn by a person. It is designed to keep a consistent movement despite the motions caused by the person's activities. A wristwatch is designed to be worn around the wrist, attached by a watch strap or other type of bracelet, including metal bands, leather straps, or any other kind of bracelet. A pocket watch is designed for a person to carry in a pocket, often attached to a chain .

Watches were developed in the 17th century from spring-powered clocks, which appeared as early as the 14th century. During most of its history the watch was a mechanical device, driven by clockwork, powered by winding a mainspring, and keeping time with an oscillating balance wheel. These are called mechanical watches.[1][2] In the 1960s the electronic quartz watch was invented, which was powered by a battery and kept time with a vibrating quartz crystal. By the 1980s the quartz watch had taken over most of the market from the mechanical watch. Historically, this is called the quartz revolution (also known as quartz crisis in Switzerland).[3][4] Developments in the 2010s include smartwatches, which are elaborate computer-like electronic devices designed to be worn on a wrist. They generally incorporate timekeeping functions, but these are only a small subset of the smartwatch's facilities.

In general, modern watches often display the day, date, month, and year. For mechanical watches, various extra features called \"complications\", such as moon-phase displays and the different types of tourbillon, are sometimes included.[5] Most electronic quartz watches, on the other hand, include time-related features such as timers, chronographs and alarm functions. Furthermore, some modern watches (like smartwatches) even incorporate calculators, GPS[6] and Bluetooth technology or have heart-rate monitoring capabilities, and some of them use radio clock technology to regularly correct the time.

Most watches that are used mainly for timekeeping have quartz movements. However, expensive collectible watches, valued more for their elaborate craftsmanship, aesthetic appeal, and glamorous design than for simple timekeeping, often have traditional mechanical movements, despite being less accurate and more expensive than their electronic counterparts.[3][4][7] As of 2018, the most expensive watch ever sold at auction was the Patek Philippe Henry Graves Supercomplication, the world's most complicated mechanical watch until 1989, fetching US$24 million (CHF 23,237,000) in Geneva on 11 November 2014.[8][9][10][11][12] As of December 2019, the most expensive watch ever sold at auction (and wristwatch) was the Patek Philippe Grandmaster Chime Ref. 6300A-010, fetching US$31.19 million (CHF 31,000,000) in Geneva on 9 November 2019.[13]

Watches evolved from portable spring-driven clocks, which first appeared in 15th-century Europe. The first timepieces to be worn, made in the 16th century beginning in the German cities of Nuremberg and Augsburg, were transitional in size between clocks and watches.[14] Nuremberg clockmaker Peter Henlein (or Henle or Hele) (1485-1542) is often credited as the inventor of the watch.[15][16] However, other German clockmakers were creating miniature timepieces during this period, and there is no evidence Henlein was the first.[16][17]

A rise in accuracy occurred in 1657 with the addition of the balance spring to the balance wheel, an invention disputed both at the time and ever since between Robert Hooke and Christiaan Huygens. This innovation increased watches' accuracy enormously, reducing error from perhaps several hours per day[21] to perhaps 10 minutes per day,[22] resulting in the addition of the minute hand to the face from around 1680 in Britain and around 1700 in France.[23]

The British predominated in watch manufacture for much of the 17th and 18th centuries, but maintained a system of production that was geared towards high-quality products for the élite.[24] The British Watch Company modernized clock manufacture with mass-production techniques and the application of duplicating tools and machinery in 1843. In the United States, Aaron Lufkin Dennison started a factory in 1851 in Massachusetts that used interchangeable parts, and by 1861 a successful enterprise operated, incorporated as the Waltham Watch Company.[25]

The concept of the wristwatch goes back to the production of the very earliest watches in the 16th century. In 1571 Elizabeth I of England received a wristwatch, described as an \"armed watch\", from Robert Dudley. The oldest surviving wristwatch (then described as a \"bracelet watch\") is one made in 1806 and given to Joséphine de Beauharnais.[26] From the beginning, wristwatches were almost exclusively worn by women - men used pocket watches up until the early-20th century.[27] In 1810, the watch-maker Abraham-Louis Breguet made a wristwatch for the Queen of Naples.[28] The first Swiss wristwatch was made by the Swiss watch-maker Patek Philippe, in the year 1868 for Countess Koscowicz of Hungary.[29][30]

Early models were essentially standard pocket-watches fitted to a leather strap, but by the early 20th century, manufacturers began producing purpose-built wristwatches. The Swiss company Dimier Frères & Cie patented a wristwatch design with the now standard wire lugs in 1903.

In 1904, Louis Cartier produced a wristwatch to allow his friend Alberto Santos-Dumont to check flight performance in his airship while keeping both hands on the controls as this proved difficult with a pocket watch.[31][32][33] Cartier still markets a line of Santos-Dumont watches and sunglasses.[34]

In 1905, Hans Wilsdorf moved to London and set up his own business, Wilsdorf & Davis, with his brother-in-law Alfred Davis, providing quality timepieces at affordable prices; the company became Rolex in 1915.[35] Wilsdorf was an early convert to the wristwatch, and contracted the Swiss firm Aegler to produce a line of wristwatches.[36]

John Harwood invented the first successful self-winding system in 1923. In anticipation of Harwood's patent for self-winding mechanisms expiration in 1930, Glycine founder Eugène Meylan started development on a self-winding system as a separate module that could be used with almost any 8.75 ligne (19.74 millimeter) watch movement. Glycine incorporated this module into its watches in October 1930 and began mass-producing automatic watches.[40]

The commercial introduction of the quartz watch in 1969 in the form of the Seiko Astron 35SQ and in 1970 in the form of the Omega Beta 21 was a revolutionary improvement in watch technology. In place of a balance wheel which oscillated at perhaps 5 or 6 beats per second, these devices used a quartz-crystal resonator which vibrated at 8,192 Hz, driven by a battery-powered oscillator circuit.[42] Most quartz-watch oscillators now operate at 32,768 Hz, although quartz movements have been designed with frequencies as high as 262 kHz. Since the 1980s, more quartz watches than mechanical ones have been marketed.[citation needed]

The crystal, also called the window or watch glass, is the transparent part of the case that allows viewing the hands and the dial of the movement.Modern wristwatches almost always use one of 4 materials:[44]

The lugs are small metal projections at both ends of the wristwatch case where the watch band attaches to the watch case.[47]The case and the lugs are often machined from one solid piece of stainless steel.[48]

The movement of a watch is the mechanism that measures the passage of time and displays the current time (and possibly other information including date, month, and day). Movements may be entirely mechanical, entirely electronic (potentially with no moving parts), or they might be a blend of both. Most watches intended mainly for timekeeping today have electronic movements, with mechanical hands on the watch face indicating the time.

Compared to electronic movements, mechanical watches are less accurate, often with errors of seconds per day; are sensitive to position, temperature,[50] and magnetism;[51] are costly to produce; require regular maintenance and adjustments; and are more prone to failures. Nevertheless, mechanical watches attract interest from consumers, particularly among watch collectors. Skeleton watches are designed to display the mechanism for aesthetic purposes.

A mechanical movement uses an escapement mechanism to control and limit the unwinding and winding parts of a spring, converting what would otherwise be a simple unwinding into a controlled and periodic energy release. The movement also uses a balance wheel, together with the balance spring (also known as a hairspring), to control gear system's motion in a manner analogous to the pendulum of a pendulum clock. The tourbillon, an optional part for mechanical movements, is a rotating frame for the escapement, used to cancel out or reduce gravitational bias. Due to the complexity of designing a tourbillon, they are expensive, and typically found in prestigious watches.

Introduced by Bulova in 1960, tuning-fork watches use a type of electromechanical movement with a precise frequency (most often 360 Hz) to drive a mechanical watch. The task of converting electronically pulsed fork vibration into rotary movements is done via two tiny jeweled fingers, called pawls. Tuning-fork watches were rendered obsolete when electronic quartz watches were developed.

Traditional mechanical watch movements use a spiral spring called a mainspring as its power source that must be rewound periodically by the user by turning the watch crown. Antique pocket watches were wound by inserting a key into the back of the watch and turning it. While most modern watches are designed to run 40 hours on a winding, requiring winding daily, some run for several days; a few have 192-hour mainsprings, requiring once-weekly winding.

A self-winding or automatic watch is one that rewinds the mainspring of a mechanical movement by the natural motions