2009年2月6日星期五

Table Pen

General description

A standard table tennis table, together with a racket and ball.
The sport is played with two or four players hitting a ball with rackets back and forth to each other on a table, in a manner similar to tennis. The rules are slightly different, but the concept is very similar. In singles play, the serve is not required to cross from the server's right-hand court to the receiver's right-hand court (or left to left) as it is in tennis. However, serving across is required in doubles play. Ball spin, speed, placement, strategy and tactics play an important part in competitive table tennis matches. The speed of the ball can vary from slow serves with much spin to smashes that travel as fast as 112.5 kilometers per hour (70 mph).
The game is played on a 274 cm × 152.5 cm × 76 cm high (9 ft × 5 ft × 30 inches high) playing surface. The International Table Tennis Federation requires an area not less than 14 m long, 7 m wide and 5 m high for competitions. No limitations in size or shape are specified.
Modern rackets usually have a thin layer of rubber covering the racket's striking surface. The rubber may have dimples pointing outwards or inwards, as well as a thin layer of sponge between the plywood center and the rubber surface. Since spin plays a large role in the modern sport of table tennis, the composition of the rubber and the combination of sponge and rubber is designed to maximize the amount of spin and speed a player can impart onto the ball. Other technological improvements include the use of carbon or other synthetic layers as part of the blade to increase the size of the sweet spot or the stiffness of the blade.
The ball used in table tennis has a diameter of 40 mm (formerly 38 mm), is made of celluloid, and is hollow. A three star rating on a ball usually implies a top quality ball, in relation to its bounce, roundness and their respective consistency between balls of the same make and type.
The winner is the first to score 11 points or more while being ahead by 2 points or more. Players alternate serves every two points. At 10-10 (or deuce) the players alternate with every serve; the winner is then the first person to gain a clear two points advantage over his opponent. The 11 point game is an International Table Tennis Federation (ITTF) change which occurred in 2001. Previously, the first player to gain 21 points (except in case of a deuce, handled as described above) won the game. All games played at national level and at international tournaments (ITTF) are now played to 11 points in either a best of five (5) games (preliminaries) or best of seven (7) games format (championship matches).

History

Table tennis depicted on a 1987 postage stamp from the GDR
The game has its origins in England as an after-dinner amusement for upper-class Victorians in the 1880s. Mimicking the game of tennis in an indoor environment, everyday objects were originally enlisted to act as the equipment. A line of books would be the net, a rounded top of a champagne cork or knot of string as the ball, and a cigar box lid as the racket.
Table tennis evolved into the modern game in Europe, the United States and Japan. The popularity of the game led game manufacturers to sell the equipment commercially. Early rackets were often pieces of parchment stretched upon a frame, and the sound generated in play gave the game its first nicknames of "whiff-whaff" and "Ping-pong." A number of sources indicate that the game was first brought to the attention of Hamley's of Regent Street under the name "Gossima". The name "ping-pong" was in wide use before English manufacturer J. Jaques & Son Ltd trademarked it in 1901. The name "Ping-Pong" then came to be used for the game played by the rather expensive Jaques equipment, with other manufacturers calling theirs table tennis. A similar situation came to exist in the United States where Jaques sold the rights to the "Ping-Pong" name to Parker Brothers.
The next major innovation was by James Gibb,an English enthusiast of table tennis, who discovered novelty celluloid balls on a trip to the U.S. in 1901 and found them to be ideal for the game. This was followed by E.C. Goode who in 1901 invented the modern version of the racket by fixing a sheet of pimpled, or stippled, rubber to the wooden blade. Table tennis was growing in popularity by 1901 when table tennis tournaments were being organized, books on table tennis were being written, and an unofficial world championship was held in 1902. During the early 20th century the game was banned in Russia due to a belief that was held by the rulers at the time that playing the game had an adverse effect on players' eyesight. In 1921, the Table Tennis Association was founded in England, and the International Table Tennis Federation followed in 1926. London hosted the first official world championship in 1927. Table tennis was introduced as an Olympic sport at the Olympics in 1988.
In the 1950s rackets that used a rubber sheet combined with an underlaying sponge layer changed the game dramatically, introducing greater spin and speed. These were introduced to England by the sports goods manufacturers S.W. Hancock Ltd. The use of speed glue increased the spin and speed even further, resulting in changes to the equipment to "slow the game down."
Toward the end of 2000, the ITTF instituted several rules changes aimed at making table tennis more viable as a televised spectator sport. First, the older 38 mm (1.5 inch) balls were officially replaced by 40 mm balls. This increased the ball's air resistance and effectively slowed down the game. By that time, players had begun increasing the thickness of the fast sponge layer on their rackets, which made the game excessively fast, and difficult to watch on television. Secondly, the ITTF changed from a 21 to an 11 point scoring system. This was intended to make games more fast-paced and exciting. The ITTF also changed the rules on service to prevent a player from hiding the ball during service, in order to increase the average length of rallies and to reduce the server's advantage. Variants of the sport have emerged. "Large-ball" table tennis uses a 44 mm ball which slows down the game significantly. This has seen some acceptance by players who have a hard time with the extreme spins and speeds of the 40 mm game. The ball's mass is 2.47 grams.
There is a move towards reviving the table tennis game that existed prior to the introduction of sponge rubber. Classic table tennis or "Hardbat" table tennis players reject the speed and spin of reversed sponge rubber, preferring the 1940-60s play style, with no-sponge, short pimpled rubber equipments, when defense is less difficult by decreasing the speed and eliminating any meaningful magnus effect of spin. Because hardbat killer shots are almost impossible to hit against a skilled player, hardbat matches focus on the strategic side of table tennis, requiring skillful maneuvering of the opponent before an attack can be successful.



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