NationMaster - Encyclopedia: Watch

A watch is a timepiece that is made to be worn on a person, as opposed to a clock which is not. The term now usually refers to a wristwatch, which is worn on the wrist with a strap, while a pocketwatch, the common type before World War I, is carried in a pocket and often has an attached chain to lift it out. Watches evolved in the 1600s from spring powered clocks, which appeared in the 1400s. In addition to the time, modern watches often display the day, date, month and year, and electronic watches may have many other functions. Look up watch in Wiktionary, the free dictionary. ... Image File history File linksMetadata Size of this preview: 300 Ã— 599 pixels Full resolution (1636 Ã— 3269 pixel, file size: 215 KB, MIME type: image/jpeg) This image was created by and for Charles David Watches,LLC. The image was created in September of 2006. ... Image File history File linksMetadata Size of this preview: 300 Ã— 599 pixels Full resolution (1636 Ã— 3269 pixel, file size: 215 KB, MIME type: image/jpeg) This image was created by and for Charles David Watches,LLC. The image was created in September of 2006. ... A clock (from the Latin cloca, bell) is an instrument for measuring time. ... For other uses, see Clock (disambiguation). ... A music tape released by Dave Grohl, under the pseudonym Late! Track listing All songs by Dave Grohl. ... â€œThe Great War â€ redirects here. ... This article is about the concept of time. ... Look up day in Wiktionary, the free dictionary. ... A date in a calendar is a reference to a particular day represented within a calendar system. ... Look up Month in Wiktionary, the free dictionary. ... A year (from Old English gÄ“r) is the time between two recurrences of an event related to the orbit of the Earth around the Sun. ...

Overview

The most common type of watch is the wristwatch, worn on the wrist and fastened with a watchband made of leather, nylon or other plastics (then called strap), metal links (called bracelet) or even ceramic. Before the inexpensive miniaturization that became possible in the 20th century, most watches were pocket watches, which had covers and were carried separately, often in a pocket and attached to a watch chain or watch fob. Image File history File links Relogio_stDumont. ... Image File history File links Relogio_stDumont. ... For the municipality in Germany, see Wrist, Germany. ... For other uses, see Leather (disambiguation). ... For other uses of this word, see nylon (disambiguation). ... This article is about metallic materials. ... Bead and wire styled Bracelet. ... This article is about ceramic materials. ... Miniaturization is a continuing trend in technology toward ever-smaller scales for first mechanical, then optical and most recently electronic devices. ... (19th century - 20th century - 21st century - more centuries) Decades: 1900s 1910s 1920s 1930s 1940s 1950s 1960s 1970s 1980s 1990s As a means of recording the passage of time, the 20th century was that century which lasted from 1901–2000 in the sense of the Gregorian calendar (1900–1999 in the... This article is about the portable timepiece. ... A gold pocket watch with hunter case attached to a watch fob A Watch fob is a medallion or ornament attached by leather strap or chain to a pocket watch to assist in locating and removing the watch from a pocket in clothing. ...

In the 21st century, technological advances in metallurgy, composite materials development and physical vapor deposition greatly influence watch design and manufacturing. Solid stainless steel, titanium, tungsten carbide, carbon fiber, high-tech ceramic and ion plating processes dominate a considerable market share of today's modern watch-making industry. Sapphire crystals are often incorporated to complement and enhance the durability of a quality watch. 20XX redirects here. ... Georg Agricola, author of De re metallica, an important early book on metal extraction Metallurgy is a domain of materials science that studies the physical and chemical behavior of metallic elements, their intermetallic compounds, and their compounds, which are called alloys. ... Vapor deposition can refer to chemical vapor deposition or physical vapor deposition. ... The 630 foot (192 m) high, stainless-clad (type 304) Gateway Arch defines St. ... General Name, symbol, number titanium, Ti, 22 Chemical series transition metals Group, period, block 4, 4, d Appearance silvery metallic Standard atomic weight 47. ... Monotungsten carbide, WC, or Ditungsten Carbide, W2C, is a chemical compound containing tungsten and carbon, similar to titanium carbide. ... Carbon fiber composite is a strong, light and very expensive material. ... This article is about ceramic materials. ... Ion plating is a physical vapor deposition technique to form metal coatings on metals and alloys. ... For other uses, see Sapphire (disambiguation). ...

Most inexpensive and medium-priced watches used mainly for timekeeping are electronic watches with quartz movements. Some watches have radio-controlled movements that are miniaturized, portable versions of radio clocks. Expensive, collectible watches valued more for their workmanship and aesthetic appeal than for simple timekeeping, often have purely mechanical movements and are powered by springs, even though mechanical movements are less accurate than more affordable quartz movements. A quartz clock A quartz clock is a timepiece that uses an electronic oscillator which is made up by a quartz crystal to keep precise time. ... A radio clock A radio clock is a clock that is synchronized by a time code bit stream transmitted by a radio transmitter connected to a time standard such as an atomic clock. ... A collectible (or collectable) is typically a manufactured item designed for people to collect. ...

Watch cases

Pocket timepieces

In the 15th century, navigation and mapping increased the desire for portability in timekeeping. The latitude could be measured by looking at the stars, but the only way a ship could measure its longitude was by comparing the midday (high noon) time of the local longitude to that of a European meridian (usually Paris or Greenwich)—a time kept on a shipboard clock. However, the process was notoriously unreliable until the introduction of John Harrison's marine chronometer. For that reason, most maps from the 15th century through the 19th century have precise latitudes but distorted longitudes. This article is about the portable timepiece. ... (14th century - 15th century - 16th century - other centuries) As a means of recording the passage of time, the 15th century was that century which lasted from 1401 to 1500. ... This article is about determination of position and direction on or above the surface of the earth. ... The word mapping has several senses: In mathematics and related technical fields, it is some kind of function: see map (mathematics). ... This article is about the geographical term. ... Longitude is the east-west geographic coordinate measurement most commonly utilized in cartography and global navigation. ... On the earth, a meridian is a north-south line between the North Pole and the South Pole. ... This article is about the capital of France. ... This article is about Greenwich in England. ... John Harrison John Harrison (March 24, 1693â€“March 24, 1776) was an English clockmaker, who designed and built the worlds first successful chronometer (maritime clock), one whose accuracy was great enough to allow the determination of longitude over long distances. ... A marine chronometer is a timekeeper precise enough to be used as a portable time standard, used to determine longitude by means of celestial navigation. ...

The first reasonably accurate mechanical clocks measured time with simple weighted pendulums, which are unworkable when irregular movement of the fulcrum occur whether at sea or in watches. The invention of a spring mechanism was crucial for portable clocks. In Tudor England, the development of "pocket-clockes" was enabled by the development of reliable springs and escapement mechanisms, which allowed clockmakers to compress a timekeeping device into a small, portable compartment. For other uses, see Pendulum (disambiguation). ... Look up Fulcrum in Wiktionary, the free dictionary. ... Allegory of the Tudor dynasty (detail), attributed to Lucas de Heere, c. ... For other uses, see England (disambiguation). ... A simple escapement. ...

In 1524, Peter Henlein created the first pocket watch.^[1] It is rumored that Henry VIII (the portrait of Henry VIII at this link shows the medallion thought to be the back of his watch) had a pocket clock which he kept on a chain around his neck. However, these watches only had an hour hand—a minute hand would have been useless because of the inaccuracy of the watch mechanism. Eventually, miniaturization of these spring-based designs allowed for accurate portable timepieces (marine chronometers) which worked well even at sea. Events March 1, 1524/5 - Giovanni da Verrazano lands near Cape Fear (approx. ... Peter Henlein (1479/1480 - August 1542) from Nuremberg is considered the inventor of the portable watch. ... Henry VIII redirects here. ... A marine chronometer is a timekeeper precise enough to be used as a portable time standard, used to determine longitude by means of celestial navigation. ...

In 1850, Aaron Lufkin Dennison founded Waltham Watch Company, which was the pioneer of the industrial manufacturing of pocket watches with interchangeable parts, the American System of Watch Manufacturing. For the game, see: 1850 (board game) 1850 (MDCCCL) was a common year starting on Tuesday (link will display the full calendar) of the Gregorian calendar (or a common year starting on Sunday [1] of the 12-day-slower Julian calendar). ... Aaron Lufkin Dennison (March 6, 1812- January 9, 1895) was an American watchmaker born in Freeport, Maine. ... The American Waltham Watch Company produced about 40 million high quality watches, clocks, speedometers, compasses, time fuses and other precision instruments between 1850 and 1950. ... Aaron Lufkin Dennison was inspired by the manufacturing techniques of the United States Armory at Springfield, Mass. ...

Breguet developed the first self-winding watch known as the perpetual in 1780.^[2]

Parts

The first two are key mechanisms within any mechanical watch of classical design; the third is optional:

NB: The pin-lever (also called Rosskopf) movement, as per the name of its inventor: Georges Frederic Roskopf: This cheaper version of the fully levered movement had been manufactured in huge quanties by many Swiss Manufacturers as well as Timex, has been replaced by Quartz movements.^[3]^[4] A simple escapement. ... Periodicity is the quality of occurring at regular intervals (e. ... Balance wheel in a cheap 1950s alarm clock, the Apollo, by Lux Mfg. ... The balance spring is a scientific device invented by Robert Hooke. ... A harmonic oscillator is either a mechanical system in which there exists a returning force F directly proportional to the displacement x, i. ... For other uses, see Pendulum (disambiguation). ... A pendulum clock uses a pendulum as its time base. ... Moment of inertia, also called mass moment of inertia and, sometimes, the angular mass, (SI units kg m2, Former British units slug ft2), is the rotational analog of mass. ... 18th century tourbillon by BrÃ©guet Girard-Perregauxs Tourbillon sous trois ponts dor, the quintescance of the tourbillon as a display of mastery in luxury watch-making A tourbillon (IPA: , French for whirlwind) is a type of mechanical clock or watch escapement invented in 1795 by Abraham-Louis... Gravity is a force of attraction that acts between bodies that have mass. ... A pin-lever watch is a lever escapement mechanical watch that uses pins on the lever, rather than jewels. ... A pin-lever or pin-pallet escapement is a lever escapement used in mechanical watches that uses metal pins on the pallet of the lever, rather than jewels. ... Georges F. Roskopf (1813-1889), the inventor of the pin-lever movement, was born in Germany and became a naturalized Swiss citizen. ... The term Timex can refer to: Timex Corporation - a large US manufacturer of watches Timex (Unix utility) - a Unix utility tool used in the measurement of duration of shell processes Timex Sinclair - a series of microcomputers, modeled on the ZX81 and ZX Spectrum Category: ...

Watch movements

A movement in watchmaking 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 a blend of the two. Most watches intended mainly for timekeeping today have electronic movements, with mechanical hands on the face of the watch indicating the time.

Mechanical movements

Purely mechanical watches are still popular. The high level of craftsmanship of purely mechanical watches accounts for much of their attraction. Compared to electronic movements, mechanical watches are inaccurate, often with errors of seconds per day. They are frequently sensitive to position and temperature, they are costly to produce, they require regular maintenance and adjustment, and they are more prone to failure. It has been suggested that this article or section be merged into Watch. ... The underside view of an automatic watch with a transparent case back. ...

Generally speaking, inexpensive and moderately priced timepieces with electronic movements now provide most users with timekeeping more accurate than the most expensive Rolex or Patek Phillipe. The most expensive, diamond encrusted Rolex contains a similar movement as its less expensive C.O.S.C rated brethren and all modern models can keep time to within 1 second a day. However, in recent times there has been less emphasis on one's watch for time precision as many people now carry multiple devices that will tell them the time accurately such as mobile phones, PDAs and laptops, these finely crafted mechanical watches have remained popular as precision time pieces and in many cases more so because of their aesthetic value as jewellery. COSC a/k/a C.O.S.C. is the Official Swiss Chronometer Testing Institute. ...

Tuning-fork movements

Tuning fork watches (introduced by Bulova in 1960) use a tuning fork at a precise frequency (most often 360 hertz) to drive a mechanical watch. Since the fork is used in place of a typical balance wheel, these watches naturally hum instead of tick. Bulova is a New York based corporation making watches and clocks. ... This article is about the SI unit of frequency. ...

The inventor, Max Hetzel, was born in Basel, Switzerland, and joined the Bulova Watch Company of Bienne, Switzerland, in 1948. Hetzel was the first to use an electronic device, a transistor, in a wristwatch. Thus, he developed the first watch that could be qualified as electronic. However, fork movements are actually more "electrical", like an old electrical wall clock, than electronic. The sweep second hand moves fluidly like that of an old electrical wall clock. Assorted discrete transistors A transistor is a semiconductor device, commonly used as an amplifier or an electrically controlled switch. ...

Such watches were also sold by Swiss watch companies under license of Bulova. In 1974, after leaving Bulova, Hetzel developed a different tuning fork drive for Omega Watches. The watch featured a cal. 1220 micromotor, and a tuning fork frequency of 720 hertz.^[5] This development was obsolete compared to the newer electronic quartz watch which had become cheaper to produce and even more accurate. It has been suggested that this article or section be merged into Federation of the Swiss Watch Industry FH. (Discuss) Most of the Swiss Watch Companies are members of the Federation of the Swiss Watch Industry FH. On the FH website, one can find the listings of all the members...

Tuning fork movements are electromechanical. The task of converting electronically pulsed fork vibration into rotary movement is done via two tiny jeweled fingers, called pawls, one of which is connected to one of the tuning fork's tines. As the fork vibrates, the pawls precisely ratchet a tiny index wheel. This index wheel has over 300 barely visible teeth and spins more than 38 million times per year. The tiny electric coils that drive the tuning fork have 8000 turns of insulated copper wire with a diameter of 0.015 mm and a length of 90 meters. This amazing feat of engineering was prototyped in the 1950s and the early 60's.

Electronic movements

Electronic movements have few or no moving parts. Essentially, all modern electronic movements use the piezoelectric effect in a tiny quartz crystal to provide a stable time base for a mostly electronic movement: the crystal forms a quartz oscillator which resonates at a specific and highly stable frequency, and which can be used to accurately pace a timekeeping mechanism. For this reason, electronic watches are often called quartz watches. Most quartz movements are primarily electronic but are geared to drive mechanical hands on the face of the watch in order to provide a traditional analog display of the time, which is still preferred by most consumers. Piezoelectricity is the ability of certain crystals to produce a voltage when subjected to mechanical stress. ... For other uses, see Quartz (disambiguation). ... A crystal oscillator is an electronic device that uses the mechanical resonance of a physical crystal of piezoelectric material to create an electrical signal with a very precise frequency. ... This article is about resonance in physics. ...

The first prototypes of electronic quartz watches were made by the CEH research laboratory in Switzerland in 1962. The first quartz watch to enter production was the Seiko 35 SQ Astron, which appeared in 1969. Modern quartz movements are produced in very large quantities, and even the cheapest wristwatches typically have quartz movements. A quartz clock A quartz clock is a timepiece that uses an electronic oscillator which is made up by a quartz crystal to keep precise time. ... Year 1962 (MCMLXII) was a common year starting on Monday (the link is to a full 1962 calendar) of the Gregorian calendar. ... Seiko Corporation ) (TYO: 8050 ) is a Japanese watch company. ... The Astron wristwatch, formally known as the Seiko Quartz-Astron 35SQ, was the worlds first quartz clock wristwatch, i. ... Also: 1969 (number) 1969 (movie) 1969 (Stargate SG-1) episode. ...

The best quartz movements are significantly more accurate than the worst, but the difference is much smaller than that found between mechanical movements and quartz movements. Quartz movements, even in their most inexpensive forms, are an order of magnitude more accurate than purely mechanical movements. Whereas mechanical movements can typically be off by several seconds a day, an inexpensive quartz movement in a child's wristwatch may still be accurate to within 500 milliseconds per day—ten times better than a mechanical movement.

Quartz mechanisms usually have a resonant frequency of 32768 Hz, chosen for ease of use (being 2¹⁵). Using a simple 15 stage divide-by-two circuit, this is turned into a 1 pulse per second signal responsible for the watch's keeping of time.

Recently, efforts have been made to combine the best features of quartz and mechanical movements. For example, the Seiko Spring Drive, introduced in 2005, uses a mainspring to power both a mechanical movement and, via a generator, a quartz regulator that controls its speed. The result is claimed to be a timepiece that operates as a mechanical watch, but with quartz accuracy. Seiko Corporation ) (TYO: 8050 ) is a Japanese watch company. ... The Spring Drive is a watch movement that was developed by Seiko. ...

Radio-controlled movements

Some electronic quartz watches are able to synchronize (time transfer) themselves with an external time source. These sources include radio time signals directly driven by atomic clocks, time signals from GPS navigation satellites, the German DCF77 signal in Europe, WWVB in the US, and others. These watches are free-running most of the time, but periodically align themselves with the chosen external time source automatically, typically once a day. Time transfer describes methods for transferring reference clock synchronization from one point to another, often over long distances. ... A time signal is a visible, audible, mechanical, or electronic signal used as a reference to determine the time of day. ... â€œNuclear Clockâ€ redirects here. ... Over fifty GPS satellites such as this NAVSTAR have been launched since 1978. ... DCF77 is a longwave time signal radio station. ... WWVB is a special NIST time signal radio station in Fort Collins, Colorado, co-located with WWV. WWVB is the station that radio-controlled clocks throughout North America use to synchronize themselves. ...

Because these watches are regulated by an external time source of extraordinarily high accuracy, they are never off by more than a small fraction of a second a day (depending on the quality of their quartz movements), as long as they can receive the external time signals that they expect. Additionally, their long-term accuracy is comparable to that of the external time signals they receive, which in most cases (such as GPS signals and special radio transmissions of time based on atomic clocks) is better than one second in three million years. For all practical purposes, then, radio-controlled wristwatches keep near perfect time.

Movements of this type synchronize not only the time of day but also the date, the leap-year status of the current year, and the current state of daylight saving time (on or off). They obtain all of this information from the external signals that they receive. Because of this continual automatic updating, they never require manual setting or resetting. For the 1921 film starring Fatty Arbuckle, see Leap Year (film). ... Although DST is common in Europe and North America, most of the worlds people do not use it. ...

A disadvantage of radio-controlled movements is that they cannot synchronize if radio reception conditions are poor. Even in this case, however, they will simply run autonomously with the same accuracy as a normal quartz watch until they are next able to synchronize.

Power sources

Springs

Traditional mechanical watch movements use a spiral spring called a mainspring as a power source. In manual watches the spring must be rewound by the user periodically by turning the watch crown. Antique pocketwatches were wound by inserting a separate key into a hole in the back of the watch and turning it. Most modern watches are designed to run 40 hours on a winding, so must be wound daily, but some run for several days and a few have 192 hour mainsprings and are wound weekly. Mainspring (U.S.A. motor spring): In a watch, long strip of hardened and blued steel or of a specially alloyed steel, between 2oo & 3oo millimeters in length and 0. ... Mainspring (U.S.A. motor spring): In a watch, long strip of hardened and blued steel or of a specially alloyed steel, between 2oo & 3oo millimeters in length and 0. ... A music tape released by Dave Grohl, under the pseudonym Late! Track listing All songs by Dave Grohl. ...

Self-winding watches

A self-winding or automatic mechanism is one that rewinds the mainspring of a mechanical movement by the natural motions of the wearer's body. The underside view of an automatic watch with a transparent case back. ... Image File history File links Download high resolution version (2560x1920, 593 KB) Work by Rama File links The following pages link to this file: Jaeger-LeCoultre ... Image File history File links Download high resolution version (2560x1920, 593 KB) Work by Rama File links The following pages link to this file: Jaeger-LeCoultre ...

The first self-winding mechanism, for pocketwatches, was invented in 1770 by Abraham-Louis Breguet;^[6] but the first "self-winding," or "automatic," wristwatch was the invention of a British watch repairer named John Harwood in 1923. This type of watch allows for a constant winding without special action from the wearer: it works by an eccentric weight, called a winding rotor, that rotates with the movement of the wearer's wrist. The back-and-forth motion of the winding rotor couples to a ratchet to automatically wind the mainspring. Self winding watches usually can also be wound manually so they can be kept running when not worn, or if the wearer's wrist motions don't keep the watch wound. Abraham-Louis Breguet or Bréguet (10 January 1747 – 17 September 1823), born in Neuchâtel in Switzerland, made many innovations in the course of a career in watchmaking in France. ... The underside view of an automatic watch with a transparent case back. ... John Harwood is an American journalist who is currently the Chief Washington Correspondent for CNBC and a Senior Contributing Writer for The Wall Street Journal. ... Year 1923 (MCMXXIII) was a common year starting on Monday (link will display the full calendar) of the Gregorian calendar. ... A ratchet lever hoist. ...

Kinetic power or automatic quartz

Some electronic watches are also powered by the movement of the wearer of the watch. Kinetic powered quartz watches make use of the motion of the wearer's arm turning a rotating weight, which turns a generator to supply power to charge a rechargeable battery that runs the watch. The concept is similar to that of self-winding spring movements, except that electrical power is generated instead of mechanical spring tension. Automatic quartz is a collective term describing watch movements that combine a self-winding rotor mechanism (as used in automatic mechanical watches) to generate electricity with a piezoelectric quartz crystal as its timing element. ... Look up generator in Wiktionary, the free dictionary. ...

Batteries

Electronic watches require electricity as a power source. Some mechanical movements and hybrid electronic-mechanical movements also require electricity. Usually the electricity is provided by a replaceable battery. The first use of electrical power in watches was as substitute for the mainspring, in order to remove the need for winding. The first electrically-powered watch, the Hamilton Electric 500, was released in 1957 by the Hamilton Watch Company of Lancaster, Pennsylvania. For other uses, see Battery. ... Hamilton pocketwatch, ca. ... , Official name: City of Lancaster Nickname: The Red Rose City Country United States State Pennsylvania County Location Penn Square - coordinates , Highest point - elevation 368 ft (112 m) Area 7. ...

Watch batteries (strictly speaking cells) are specially designed for their purpose. They are very small and provide tiny amounts of power continuously for very long periods (several years or more). In most cases, replacing the battery requires a trip to a watch-repair shop or watch dealer; this is especially true for watches that are designed to be water-resistant, as special tools and procedures are required to ensure that the watch remains water-resistant after battery replacement. Silver-oxide and lithium batteries are popular today; mercury batteries, formerly quite common, are no longer used, for environmental reasons. Cheap batteries may be alkaline, of the same size as silver-oxide but providing shorter life. Rechargeable batteries are used in some solar powered watches. Type CR2032 watch battery (lithium anode, 3 V, 20. ...

Light-powered watches

Some electronic watches are powered by light. A photovoltaic cell on the face (dial) of the watch converts light to electricity, which in turn is used to charge a rechargeable battery or capacitor. The movement of the watch draws its power from the rechargeable battery or capacitor. As long as the watch is regularly exposed to fairly strong light (such as sunlight), it never needs battery replacement, and some models need only a few minutes of sunlight to provide weeks of energy (as in the Citizen Eco-Drive). A photovoltaic cell is a device that turns light into electric energy. ... A dial is a generally a flat disk, often with numbers or similar markings on it, used for displaying the setting or output of a timepiece, radio or measuring instrument In telephony and telecommunications in connection with a telephone, a dial refers, in older telephones, to a rotating disk with... See Capacitor (component) for a discussion of specific types. ... A rechargeable lithium polymer Nokia mobile phone battery. ... Eco-Drive is a type of solar powered wrist watches manufactured by the Citizen Watch Co. ...

Some of the early solar watches of the 1970s had innovative and unique designs to accommodate the array of solar cells needed to power them (Synchronar, Nepro, Sicura and some models by Cristalonic, Alba, Seiko and Citizen). As the decades progressed and the efficiency of the solar cells increased while the power requirements of the movement and display decreased, solar watches began to be designed to look like other conventional watches.^[7]

Some critics point out that both the low cost of quartz watches and the extreme longevity of the newest lithium-ion batteries (said to be upwards of ten years in some watches) may make solar power, whilst an interesting technology, obsolete before it truly catches on. According to this view, battery-powered watches will become disposable items, so the purchaser will not care about the cost of replacing the battery. However, some purchasers may be persuaded by the ecological benefits of solar watches: less waste and lower energy input, not to mention the reduced hassle of not having to purchase a replacement watch every few years. In addition, the widespread use of watches as jewelry--worn as much for their aesthetic value as their timekeeping ability--makes the prospect of disposable watches less attractive. For other uses, see Waste (disambiguation). ...

Thermal power

A seldom used power source is the temperature difference between the wearer's arm and the surrounding environment (as applied in the Citizen Eco-Drive Thermo). Citizen Watch Co. ... Eco-Drive is a type of solar powered wrist watches manufactured by the Citizen Watch Co. ...

Displaying the time

Analog display

Traditionally, watches have displayed the time in analog form, with a numbered dial upon which are mounted at least a rotating hour hand and a longer, rotating minute hand. Many watches also incorporate a third hand that shows the current second of the current minute. Watches powered by quartz have second hands that snap every second to the next marker. Watches powered by a mechanical movement have a "sweep second hand", the name deriving from its uninterrupted smooth (sweeping) movement across the markers, although this is actually a misnomer; the hand merely moves in smaller steps, typically 1/6 of a second, corresponding to the beat of the balance wheel. All of the hands are normally mechanical, physically rotating on the dial, although a few watches have been produced with “hands” that are simulated by a liquid-crystal display. LCD redirects here. ...

Analog display of the time is nearly universal in watches sold as jewelry or collectibles, and in these watches, the range of different styles of hands, numbers, and other aspects of the analog dial is very broad. In watches sold for timekeeping, analog display remains very popular, as many people find it easier to read than digital display; but in timekeeping watches the emphasis is on clarity and accurate reading of the time under all conditions (clearly marked digits, easily visible hands, large watch faces, etc.). They are specifically designed for the left wrist with the stem (the knob used for changing the time) on the right side of the watch, this makes it easy to change the time without removing the watch from the hand.

Digital display

Since the advent of electronic watches that incorporate small computers, digital displays have also been available. A digital display simply shows the time as a number, e.g., 12:40 AM instead of a short hand pointing towards the number 12 and a long hand pointing towards the number 8 on a dial. Some watches, such as the Timex Datalink USB, feature dot matrix displays. The model 150. ... A dot matrix is an array of dots used to generate characters, symbols and images. ...

The first digital watch, a Pulsar prototype in 1970, was developed jointly by Hamilton Watch Company and Electro-Data. John Bergey, the head of Hamilton's Pulsar division, said that he was inspired to make a digital timepiece by the then-futuristic digital clock that Hamilton themselves made for the 1968 science fiction film 2001: A Space Odyssey. On April 4, 1972 the Pulsar was finally ready, made in 18-carat gold and sold for $2,100 at retail. It had a red light-emitting diode (LED) display. Another early digital watch innovator, Roger Riehl's Synchronar Mark 1, provided an LED display and used solar cells to power the internal nicad batteries.^[8] Most watches with LED displays required that the user press a button to see the time displayed for a few seconds, because LEDs used so much power that they could not be kept operating continuously. Watches with LED displays were popular for the next few years, but soon the LED displays were superseded by liquid crystal displays (LCDs), which used less battery power and were much more convenient in use, with the display always visible and no need to push a button before seeing the time.. The first LCD watch with a six-digit LCD was the 1973 Seiko 06LC, although various forms of early LCD watches with a four-digit display were marketed as early as 1972 including the 1972 Gruen Teletime LCD Watch, and the Cox Electronic Systems Quarza.^[9]^[10] Pulsar was originally the brand established by Hamilton for the first digital watch. ... Year 1970 (MCMLXX) was a common year starting on Thursday (link shows full calendar) of the Gregorian calendar. ... Hamilton pocketwatch, ca. ... is the 94th day of the year (95th in leap years) in the Gregorian calendar. ... Year 1972 (MCMLXXII) was a leap year starting on Saturday (link will display full calendar) of the Gregorian calendar. ... â€œLEDâ€ redirects here. ... LCD redirects here. ... For the song by James Blunt, see 1973 (song). ... Seiko Corporation ) (TYO: 8050 ) is a Japanese watch company. ...

Digital watches were very expensive and out of reach to the common consumer up until 1975, when Texas Instruments started to mass produce LED watches inside a plastic case. These watches, which first retailed for only $20, and then $10 in 1976, saw Pulsar lose $6 million and the brand sold to competitors twice in only a year, eventually becoming a subsidiary of Seiko and going back to making only analogue quartz watches. Year 1975 (MCMLXXV) was a common year starting on Wednesday (link will display full calendar) of the Gregorian calendar. ... Texas Instruments (NYSE: TXN), better known in the electronics industry (and popularly) as TI, is an American company based in Dallas, Texas, USA, renowned for developing and commercializing semiconductor and computer technology. ... Year 1976 Pick up sticks(MCMLXXVI) was a leap year starting on Thursday (link will display full calendar) of the Gregorian calendar. ...

From the 1980s onward, technology in digital watches vastly improved. In 1982 Seiko produced a watch with a small TV screen built in and Casio produced a digital watch with a thermometer and another watch that could translate 1,500 Japanese words into English. In 1985, Casio produced the CFX-400 scientific calculator watch. In 1987 Casio produced a watch that could dial your telephone number and Citizen revealed one that would react to your voice. In 1995 Timex release a watch which allowed the wearer to download and store data from a computer to their wrist. Since their apex during the late 1980s to mid 1990s high technology fad, digital watches have mostly devolved into a simpler, less expensive basic time piece with little variety between models. Year 1980 (MCMLXXX) was a leap year starting on Tuesday (link displays the 1980 Gregorian calendar). ...

Despite these many advances, almost all watches with digital displays today are not considered an impressive form of jewelry and most are seen as being in the category of simple timekeeping watches.

Expensive watches for collectors rarely have digital displays since there is little demand for them. Less craftsmanship is required to make a digital watch face and most collectors find that analog dials (especially with complications) vary in quality more than digital dials due to the details and finishing of the parts that make up the dial (thus making the differences between a cheap and expensive watch more evident). In horology terms, a complication in a mechanical timepiece is any feature beyond that of a simple hours, minutes, and seconds movement. ...

Watch functions

All watches provide the time of day, giving at least the hour and minute, and usually the second. Most also provide the current date, and often the day of the week as well. However, many watches also provide a great deal of information beyond the basics of time and date.

Other elaborated and more expensive watches, both pocket and wrist models, also incorporate striking mechanisms or repeater functions, so that the wearer could learn the time by the sound emanating from the watch. This announcement or striking feature is an essential characteristic of true clocks and distinguishes such watches from ordinary timepieces. This feature is available on most digital watches. Big Ben, the tower clock of the Palace of Westminster in London, is a famous striking clock. ... The minute repeater is a complication found in a mechanical watch, in which the time is struck to the nearest minute. ... For other uses, see Clock (disambiguation). ...

Complicated watches

A complicated watch has one or more functionalities beyond the basic function of displaying the time and the date; such a functionality is called a complication. Two popular complications are the chronograph complication, which is the ability of the watch movement to function as a stopwatch, and the moonphase complication, which is a display of the lunar phase. Other more expensive complications include, Tourbillion, Perpetual calendar, Minute repeater and Equation of time. A truly complicated watch has many of these complications at once (see Calibre 89 from Patek Phillipe for instance). In horology terms, a complication in a mechanical timepiece is any feature beyond that of a simple hours, minutes, and seconds movement. ... Pocket chronograph Russia Poljot Aviator watch with P3133 chronograph movement. ... A stopwatch is a timepiece designed to measure the amount of time elapsed from a particular time when activated to when the piece is deactivated. ... Moon phase redirects here. ... For other uses, see Tourbillon (disambiguation). ... A perpetual calendar is a calendar which is good for a span of many years, such as the Runic calendar. ... The minute repeater is a complication found in a mechanical watch, in which the time is struck to the nearest minute. ... The equation of time is the difference, over the course of a year, between time as read from a sundial and a clock. ... Image:PatekPhilippeCalibre89. ... Patek Philippe & Co. ...

Chronographs and chronometers

The similar-sounding terms chronograph and chronometer are often confused, although they mean altogether different things. A chronograph is a type of complication, as explained above. A chronometer watch is an all-mechanical watch or clock whose movement has been tested and certified to operate within a certain standard of accuracy by the COSC (Contrôle Officiel Suisse des Chronomètres). The concepts are different but not mutually exclusive; a watch can be a chronograph, a chronometer, both, or neither. Image File history File links Size of this preview: 399 Ã— 599 pixelsFull resolution (550 Ã— 826 pixels, file size: 58 KB, MIME type: image/jpeg) // I, the copyright holder of this work, hereby release it into the public domain. ... Image File history File links Size of this preview: 399 Ã— 599 pixelsFull resolution (550 Ã— 826 pixels, file size: 58 KB, MIME type: image/jpeg) // I, the copyright holder of this work, hereby release it into the public domain. ... A chronometer watch is a watch tested and certified to meet certain precision standards. ... COSC a/k/a C.O.S.C. is the Official Swiss Chronometer Testing Institute. ...

However, since COSC only deals with watches manufactured/assembled in Switzerland, it is a norm of less importance^{[citation needed]}. Some^{[attribution needed]} German and Japanese movements surpass these requirements,^{[citation needed]} but are not allowed to enter the COSC race.^{[citation needed]}

Second display

Some watches include a second 12-hour display for UTC (as Pontos Grand Guichet GMT). ... Maurice Lacroix is a brand of Swiss watches from the Canton of Jura. ...

Types of watch

Fashionable watches

At the end of the 20th century, Swiss watch makers were seeing their sales go down as analog clocks were considered obsolete. They joined forces with designers from many countries to reinvent the Swiss watch.

The result was that they could considerably reduce the pieces and production time of an analog watch. In fact it was so cheap that if a watch broke it would be cheaper to throw it away and buy a new one than to repair it. One of these Swiss watch manufacturers (today named The Swatch Group Ltd.) started a new brand, Swatch, and called graphic designers to redesign a new annual collection. This article does not cite any references or sources. ... For other uses, see Swatch (disambiguation). ...

This is often used as a case study in design schools to demonstrate the commercial potential of industrial and graphic design.

Dual time watches

A dual time watch is designed for travelers, allowing them to see what time it is at home when they are elsewhere.

Collectible and jewelry watches

Wristwatches are often treated as jewelry or as collectible works of art rather than as timepieces. This has created several different markets for wristwatches, ranging from very inexpensive but accurate watches intended for no other purpose than telling the correct time, to extremely expensive watches that serve mainly as personal adornment or as examples of high achievement in miniaturization and precision mechanical engineering. Still another market is that of “geek watches”—watches that not only tell the time, but incorporate computers, satellite navigation, complications of various orders, and many other features that may be quite removed from the basic concept of timekeeping.

Most companies that produce watches specialize in one of these markets. Companies such as Breitling, Patek Phillipe, Jaeger-LeCoultre, Omega and Rolex specialize in watches as jewelry or fine mechanical devices, while companies such as Casio specialize in watches as timepieces or multifunctional computers. Since watches are considered by many to be both functional and attractive, there are many types and manufacturers to choose from. Breitling logo Breitling is a brand of Swiss watches from the Canton of Jura. ... Patek Philippe & Co. ... Jaeger-LeCoultre Master Control: rÃ©serve de marche, date on hand. ... Look up Î©, Ï‰ in Wiktionary, the free dictionary. ... Rolex SA is a Swiss manufacturer of mostly mechanical wristwatches and accessories renowned for their dependability, prestige, and cost (from a few thousand to more than one hundred thousand U.S. dollars). ... Casio Computer Co. ...

Important collectible American made watches from the early 20th Century were the best available at any price. Leading watchmakers included Elgin, Gruen, Hamilton, and Illinois. Hamilton is generally considered as having the finest early American movements, while the art deco styling of The Illinois Watch Company was unsurpassed worldwide^{[citation needed]}. Early Gruen Curvex models remain very desired for how they entwined form and function^{[citation needed]}, and Elgin made more watches than anyone else^{[citation needed]}.

Computerized multi-function watches

Many technological enhancements to wristwatches have been explored but most of them remained unnoticed. In 2005 for example, one company marketed an alarm wristwatch called the Sleeptracker with an accelerometer inside that monitors the user's sleep and rings during one of his almost-awake phases which is considered to be the optimum wake-up time.^[11]

A number of functionalities not directly related to time have also been inserted into watches. As miniaturized electronics became cheaper, watches have been developed containing calculators, tonometers, video games, digital cameras, keydrives, GPS receivers and cellular phones. For other uses, see Calculator (disambiguation). ... A Tonometer is a device used to measure Intraocular pressure. ... Computer and video games redirects here. ... Look up digital camera in Wiktionary, the free dictionary. ... A USB keydrive, shown with a US quarter coin for scale. ... Over fifty GPS satellites such as this NAVSTAR have been launched since 1978. ... Cellular redirects here. ...

In the early 1980s Seiko marketed a watch with a television in it, although at the time television receivers were too bulky to fit in a wristwatch, and the actual receiver and its power source were in a book-sized box with a cable that ran to the wristwatch. In the early 2000s, a self-contained wristwatch television receiver came on the market, with a strong enough power source to provide one hour of viewing. Seiko Corporation ) (TYO: 8050 ) is a Japanese watch company. ...

These watches have not had sustained long-term sales success. As well as awkward user interfaces due to the tiny screens and buttons possible in a wearable package, and in some cases short battery life, the functionality available has not generally proven sufficiently compelling to attract buyers. Such watches have also had the reputation as ugly and thus mainly geek toys. Now with the ubiquity of the mobile phone in many countries, which have bigger screens, buttons, and batteries, interest in incorporating extra functionality in watches seems to have declined. The user interface is the part of a system exposed to users. ... The word geek is a slang term, noting individuals as a peculiar or otherwise dislikable person, especially one who is perceived to be overly intellectual.[1] Formerly, the term referred to a carnival performer often billed as a wild man whose act usually includes biting the head off a live...

Several companies have however attempted to develop a computer contained in a wristwatch (see also wearable computer). As of 2005, the only programmable computer watches to have made it to market are the Timex Datalink, Seiko Ruputer, the Matsucom onHand, and the Fossil, Inc. Wrist PDA, although many digital watches come with extremely sophisticated data management software built in. This article is about the machine. ... To meet Wikipedias quality standards, this article or section may require cleanup. ... Year 2005 (MMV) was a common year starting on Saturday (link displays full calendar) of the Gregorian calendar. ... The model 150. ... The Ruputer was a wristwatch-sized wearable computer developed in 1998 by Seiko. ... Fossil, Inc. ... Fossil Wrist PDA is a Personal Digital Assistant designed to take the place of a wristwatch. ...

Spacewatches

Zero gravity environment and other extreme conditions encountered by astronauts in space requires the use of specially tested watches. Image File history File links OMEGA-Speedmaster-Professional-Front. ... Image File history File links OMEGA-Speedmaster-Professional-Front. ... Omega SA is a watch company based in Biel/Bienne Switzerland and is one of the more prestigious brands in timepieces. ... The Omega Speedmaster, the legendary Moonwatch, selected by NASA for all the Apollo missions Launched in 1957 by Omega, the Moonwatch is a type of Omega Speedmaster watch which was selected by the NASA for the Project Apollo. ... Zero gravity redirects here. ... For other uses, see Astronaut (disambiguation). ...

On April 12, 1961, Yuri Gagarin wore a Shturmanskie (a transliteration of Штурманские which actually means "navigators") wristwatch during his historic first flight into space. The Shturmanskie was manufactured at the First Moscow Watch Factory. is the 102nd day of the year (103rd in leap years) in the Gregorian calendar. ... Year 1961 (MCMLXI) was a common year starting on Sunday (link will display full calendar) of the Gregorian calendar. ... â€œGagarinâ€ redirects here. ...

Since 1964, the watches of the First Moscow Factory have been marked by a trademark "ПОЛЕТ" and "POLJOT", which means "flight" in Russian and is a tribute to the number of many space trips its watches have accomplished.

In the late 1970s, Poljot launched a new chrono movement, the 3133. With a 23 jewel movement and manual winding (43 hours), it was a modified Russian version of the Swiss Valjoux 7734 of the early 1970s. Poljot 3133 were taken into space by astronauts from Russia, France, Germany and Ukraine. On the arm of Valeriy Polyakov, a Poljot 3133 chronograph movement-based watch set a space record for the longest space flight in history. Poljot (pronounced PIE-yot, a transliteration of ÐŸÐžÐ›Ð•Ð¢, literally meaning FLIGHT), a brand of watches from Russia, was produced by the First Moscow Watch Factory. ... Valeriy Vladimirovich Polyakov (Russian: , Valeriy VladmiroviÄ Poljakov) (born April 27, 1942) is the Russian cosmonaut holding the record for the longest spaceflight in human history, staying aboard the Mir space station for more than 14 months during one trip. ...

During the 1960s, a large range of watches were tested for durability and precision under extreme temperature changes and vibrations. The Omega Speedmaster was selected by U.S. space agencies. Omega SA is a watch company based in Biel/Bienne Switzerland and is one of the more prestigious brands in timepieces. ...

TAG Heuer became the first Swiss watch in space thanks to an Heuer Stopwatch, worn by John Glenn in 1962 when he piloted the Friendship 7 on the first manned U.S. orbital mission. TAG Heuer Carrera Automatic Chronograph with Tachymetre TAG Heuer (pronounced: tÃ¤g-hoi-er) is a Swiss watchmaker known for its mid - high range sports watches and chronographs. ... For other persons named John Glenn, see John Glenn (disambiguation). ... Crew John Glenn Backup Crew M. Scott Carpenter Mission Parameters Mass: 1,352 kg Perigee: 159 km Apogee: 265 km Inclination: 32. ...

The Breitling Navitimer Cosmonaute was designed with a 24-hour analog dial to avoid confusion between AM and PM, which are meaningless in space. It was first worn in space by U.S. astronaut Scott Carpenter on May 24, 1962 in the Aurora 7 mercury capsule.^[12] a Vostok 24 hour watch reading 09:54 Shepherd Gate clock outside the Royal Greenwich Observatory The clock at Ottery St Mary, England, showing nearly noon, using the 12 hour time system on a 24 hour analog dial. ... Astronaut M. Scott Carpenter inspects the heat shield of his Aurora 7 space capsule Malcolm Scott Carpenter (born May 1, 1925) was one of the original seven astronauts selected in 1959 for Project Mercury. ... is the 144th day of the year (145th in leap years) in the Gregorian calendar. ... Year 1962 (MCMLXII) was a common year starting on Monday (the link is to a full 1962 calendar) of the Gregorian calendar. ... Alternate meaning: Mercury Seven Crew Scott Carpenter The original prime crew for Mercury Atlas-7 was Deke Slayton, however Slayton was controversially removed from all flight crew availability after the discovery of cardiac arrhythmia during a training run in the G-loading centrifuge. ...

Since 1994 Fortis is the exclusive supplier for manned space missions authorized by the Russian Federal Space Agency. This article does not cite any references or sources. ... The Russian Federal Space Agency (Russian: Ð¤ÐµÐ´ÐµÑ€Ð°Ð»ÑŒÐ½Ð¾Ðµ ÐºÐ¾ÑÐ¼Ð¸Ñ‡ÐµÑÐºÐ¾Ðµ Ð°Ð³ÐµÐ½Ñ‚ÑÑ‚Ð²Ð¾ Ð Ð¾ÑÑÐ¸Ð¸, commonly known as Roskosmos) or RKA, formerly the Russian Aviation and Space Agency (Russian: Ð Ð¾ÑÑÐ¸Ð¹ÑÐºÐ¾Ðµ Ð°Ð²Ð¸Ð°Ñ†Ð¸Ð¾Ð½Ð½Ð¾-ÐºÐ¾ÑÐ¼Ð¸Ñ‡ÐµÑÐºÐ¾Ðµ Ð°Ð³ÐµÐ½Ñ‚ÑÑ‚Ð²Ð¾, commonly known as Rosaviakosmos), is the government agency responsible for Russias space science programme and general aerospace research. ...

China National Space Administration (CNSA) astronauts wear the Fiyta^[13] spacewatches. The China National Space Administration (CNSA) () is the civilian agency of the government of the Peoples Republic of China responsible for the national space program. ...

FLIGHT-QUALIFIED BY NASA FOR SPACE MISSIONS: Omega SA is a watch company based in Biel/Bienne Switzerland and is one of the more prestigious brands in timepieces. ... The Omega Speedmaster, the legendary Moonwatch, selected by NASA for all the Apollo missions. ...

Omega SA is a watch company based in Biel/Bienne Switzerland and is one of the more prestigious brands in timepieces. ... Casio Computer Co. ... G-Shock DW-6600 G-Shock is a style of watch manufactured by Casio, famous for its resistance to shock (e. ... --Kuzaar 13:48, 15 May 2006 (UTC) Categories: ... Casio Computer Co. ... G-Shock DW-6600 G-Shock is a style of watch manufactured by Casio, famous for its resistance to shock (e. ... A DW-5600E-1V G-Shock. ... Casio Computer Co. ... G-Shock DW-6600 G-Shock is a style of watch manufactured by Casio, famous for its resistance to shock (e. ... Casio Computer Co. ... G-Shock DW-6600 G-Shock is a style of watch manufactured by Casio, famous for its resistance to shock (e. ... Casio Computer Co. ... G-Shock DW-6600 G-Shock is a style of watch manufactured by Casio, famous for its resistance to shock (e. ... The Master of G series were a collection of G-Shock watches produced by Japanese electronics and wristwatch manufacturer Casio in the late 1990s. ... Timex Group B.V. is an American watch company. ... The model 150. ...

Materials

Watchmaking industry uses materials traditionally applied in the field of horology, as well as most innovative materials borrowed from the automotive, aerospace and medical industries. The most common and widely used materials for the production of watch cases are the following: gold, steel, platinum, titanium, aluminum, and carbon fiber. GOLD refers to one of the following: GOLD (IEEE) is an IEEE program designed to garner more student members at the university level (Graduates of the Last Decade). ... For other uses, see Steel (disambiguation). ... General Name, Symbol, Number platinum, Pt, 78 Chemical series transition metals Group, Period, Block 10, 6, d Appearance grayish white Standard atomic weight 195. ... General Name, symbol, number titanium, Ti, 22 Chemical series transition metals Group, period, block 4, 4, d Appearance silvery metallic Standard atomic weight 47. ... Aluminum is a soft and lightweight metal with a dull silvery appearance, due to a thin layer of oxidation that forms quickly when it is exposed to air. ... Carbon fiber composite is a strong, light and very expensive material. ...

Some other materials, such as resin, rubber and plastic are often applied for producing cases of sports watch models. These materials are sturdy, light, water- and corrosion-resistant. This article does not cite any references or sources. ... This does not cite any references or sources. ... For other uses, see Plastic (disambiguation). ...

Watchmakers experiment with new types of materials and develop timepieces using innovative metallurgical combinations, silicon-improved movements and cases produced from high-tech ceramic, the material used as a heat shield for protection of U.S. space shuttles re-entering the earth's atmosphere. Experimenting with new materials, watchmaking brands produce their cases and movements using exotic metals, such as palladium, magnesium and arcane alloys. This article is about ceramic materials. ... For other uses, see Palladium (disambiguation). ... General Name, symbol, number magnesium, Mg, 12 Chemical series alkaline earth metals Group, period, block 2, 3, s Appearance silvery white solid at room temp Standard atomic weight 24. ...

Hublot is one of the brands actively involved in discovering and using new materials for watch production. The brand produced the first luxury gold watch on a natural rubber strap. In 2005, Hublot introduced its Big Bang, a mechanical chronograph that incorporated gold, ceramic, Kevlar, tantalum, tungsten, carbon and rubber. Year 2005 (MMV) was a common year starting on Saturday (link displays full calendar) of the Gregorian calendar. ... General Name, Symbol, Number tantalum, Ta, 73 Chemical series transition metals Group, Period, Block 5, 6, d Appearance gray blue Standard atomic weight 180. ... For other uses, see Tungsten (disambiguation). ...

Patek Philippe, Ulysses Nardin and other brands experiment with silicon, the material that eliminates the need for oil, thus reducing the amount of friction and prolonging the life of a watch movement. Patek Philippe & Co. ... Not to be confused with Silicone. ...

High-tech ceramic is one more widely-used material among watchmakers. It is light-weight, scratch-resistant, durable and smooth.^[14]

Water resistance

Watches may be crafted to become water resistant. These watches are sometimes called diving watches when they are suitable for scuba diving or saturation diving. The International Organization for Standardization issued a standard for water resistant watches which also prohibits the term "waterproof" to be used with watches, which many countries have adopted. Water resistance is achieved by the gaskets which form a watertight seal, used in conjunction with a sealant applied on the case to help keep water out. The material of the case must also be tested in order to pass as water resistant.^[15] Diving watches are watches that feature, as a minimum, a water resistance greater than 10 ATM, the equivilant of 300ft/100m. ... Scuba diving is swimming underwater while using self-contained breathing equipment. ... Saturation diving is a diving technique that allow divers to remain at great depth for long periods of time, by living under pressure in special living chamber complexes affixed to a diving support vessel, oil platform or other floating work station. ... â€œISOâ€ redirects here. ... Some seals and gaskets 1. ...

The watches are tested in still water, thus a watch with a 50 meter rating will be water resistant if it is stationary and under 50 meters of still water. For normal use, the ratings must then be translated from the pressure the watch can withstand to take into account the extra pressure generated by motion. Watches are classified by their degree of water resistance, which roughly translates to the following:^[16]

Some watches use bar instead of meters, which may then be multiplied by 10 to be approximately equal to the rating based on meters. Therefore, a 10 bar watch is equivalent to a 100 meter watch. Some watches are rated in atmospheres (atm), which are roughly equivalent to bar. Free-diver with monofin, ascending. ... The bar (symbol bar), decibar (symbol dbar) and the millibar (symbol mbar, also mb) are units of pressure. ... Standard atmosphere (symbol: atm) is a unit of pressure. ...

Gallery

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