Elements used in watches

The mechanical watches

The mechanical clock consists of a complicated series of wheels, gears, and levers powered by a falling weights and with a pendulum. These critical pieces move together. The hands on a dial to show the time. The addition of bells on the hour, half hour, and quarter hour followed soon afterward. By the eighteenth century, smaller clocks for the home were available, and, unlike their predecessors, were closed and sealed in a case.

After the World War II, improvement in atomic physics led to the development of the atomic clock. Radioactive materials produce particles at a known, steady rate. The parts of a mechanical clock that ratcheted to keep the time could be replaced by a device that stimulated the watch movement each time a particle was produced by the radioactive element. Atomic clocks, incidentally, are still made and sold, and they are found to be consistently accurate.

The electrical watches

In the 1970s and 1980s, a new type of watch was invented With the development of the microchip. Wristwatches that consist of microchip technology with quartz crystals became the standard at that time; we now hardly found non-quartz wristwatches these days. The microchip helps to send signals to the dial of the watch continuously. Because it is not a mechanical device with moving parts, it does not even wear out.

The use of quartz in watches makes use of a long-known type of electricity known as piezoelectricity. Piezoelectricity is the current which flows from a piece of quartz when the quartz is put under electrical or mechanical pressure. A quartz watch uses the electricity from a piece of quartz subjected to the electricity from a battery to send.

The heart of a quartz watch is a tiny sliver of quartz. In a natural way, quartz is first loaded into a giant autoclave. Hanging from the top of the autoclave are seeds or tiny particles of quartz with the desired crystalline structure. An alkaline material is pumped into the bottom of the autoclave, and the autoclave is heated to a high temperature, dissolving the quartz in the hot alkaline liquid, evaporating it, and depositing it on the seeds. After about 75 days, the chamber can be opened, and the newly grown quartz crystals can be removed and cut into the correct proportions. A regular, countable series of signals to one or more microchips.

The most accurate quartz watches are those in which the time appears in an electronically controlled digital display, produced via a light-emitting diode (LED) or a liquid crystal display (LCD). It is possible, of course, to have the microprocessor send its signals to mechanical devices that make hands move on the watch face, creating an analog display. But because the hands are mechanically operated through a portion of the watch known as a gear train, analogue watches usually are not as accurate as digitals and are subject to wear. Both types of watches achieve tremendous accuracy, with digital watches commonly being accurate to within three seconds per month.

Raw materials of electronic watches

Electronic watches make use of many of the most modern materials available, including plastics and alloy metals. Cases can be made of either plastic or metal; watches with metal cases often include a stainless steel backing. Microchips are typically made of silicon, while LEDs are usually made of gallium arsenide, gallium phosphide, or gallium arsenide phosphide. LCDs consist of liquid crystals sandwiched between glass pieces. Electrical contacts between parts are usually made of a small amount of gold (or are goldplated); gold is an almost ideal electrical conductor and can be used successfully in very small amounts


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