Mechanical television - AbsoluteAstronomy.com

Mechanical television was a broadcast television system

Broadcast television system

Broadcast television systems are encoding or formatting standards for the transmission and reception of terrestrial television signals. There are three main analog television systems in current use around the world: NTSC, PAL, and SECAM...

that used mechanical

Mechanics

Mechanics is the branch of physics concerned with the behavior of physical bodies when subjected to forces or displacements, and the subsequent effects of the bodies on their environment....

or electromechanical devices to capture and display video

Video

Video is the technology of electronically capturing, recording, processing, storing, transmitting, and reconstructing a sequence of still images representing scenes in motion.- History :...

images. However, the images themselves were usually transmitted electronically

Electronics

Electronics is the branch of science, engineering and technology that deals with electrical circuits involving active electrical components such as vacuum tubes, transistors, diodes and integrated circuits, and associated passive interconnection technologies...

and via radio wave

Radio Wave

Radio Wave may refer to:*Radio frequency*Radio Wave 96.5, a radio station in Blackpool, UK...

s. The reason for the dual nature of mechanical television lay in the history of technology.

The earliest mechanical television components originated with 19th century inventors, with 20th century inventors later adding electronic components as they were created. Mechanical systems were used in television broadcasting from 1925 to 1939, overlapping the all-electronic television era by three years.

Mechanical television in history

The essential mechanical component usually consisted of a Nipkow disk

Nipkow disk

A Nipkow disk , also known as scanning disk, is a mechanical, geometrically operating image scanning device, invented by Paul Gottlieb Nipkow...

, which has a series of holes in a spiral pattern. In the camera, the disk had a light-detecting device, usually a photoelectric cell, behind it. In the reproducer (the display), a modulated light source, usually used a neon tube, replacing the light detector. As each hole flew by, it produced a scan line

Scan line

A scan line or scanline is one line, or row, in a raster scanning pattern, such as a line of video on a cathode ray tube display of a television set or computer monitor....

. An AM radio wave or closed circuit then carried the scan line to the TV reproducer.

Facsimile transmission of still photographs employed some of the principles of mechanical television as early as the 19th century. For instance, Shelford Bidwell

Shelford Bidwell

Shelford Bidwell was an English physicist and inventor. He is best known for his work with "telephotography", a precursor to the modern fax machine.-Private Life:...

demonstrated such a system in 1881. For decades, earlier systems had pioneered scanning in the transmission of type and line art. Photographic transmission was a greater challenge due to the selenium

Selenium

Selenium is a chemical element with atomic number 34, chemical symbol Se, and an atomic mass of 78.96. It is a nonmetal, whose properties are intermediate between those of adjacent chalcogen elements sulfur and tellurium...

in early photoelectric cells having very low sensitivities. Scanning a photograph at a resolution suitable for newspaper reproduction could take several minutes. With silhouette or duotone still images, instantaneous transmission was possible by 1909.

American inventor Charles Francis Jenkins

Charles Francis Jenkins

Charles Francis Jenkins was an American pioneer of early cinema and one of the inventors of television, though he used mechanical rather than electronic technologies...

developed mechanical television systems in the 1920s and early 1930s. In 1923, Jenkins transmitted the first moving silhouette

Silhouette

A silhouette is the image of a person, an object or scene consisting of the outline and a basically featureless interior, with the silhouetted object usually being black. Although the art form has been popular since the mid-18th century, the term “silhouette” was seldom used until the early decades...

images, and on June 13, 1925 publicly demonstrated synchronized transmission of images and sound. Over 400 patents were issued to Jenkins, including 75 devoted to mechanical television alone. In the 1920s, the Japanese electrical scientist Yasujiro Niwa

Yasujiro Niwa

was a Japanese electrical scientist. In the 1920s, he invented a simple device for phototelegraphic transmission through cable and later via radio, a precursor to mechanical television. He later became the Director of the Department of Electronic Engineering of University of Tokyo. He was awarded...

invented a simple device for phototelegraphic transmission through cable

Cable

A cable is two or more wires running side by side and bonded, twisted or braided together to form a single assembly. In mechanics cables, otherwise known as wire ropes, are used for lifting, hauling and towing or conveying force through tension. In electrical engineering cables are used to carry...

and later via radio

Radio

Radio is the transmission of signals through free space by modulation of electromagnetic waves with frequencies below those of visible light. Electromagnetic radiation travels by means of oscillating electromagnetic fields that pass through the air and the vacuum of space...

.

Mechanical television transmitting a live, moving image in tone gradations (grayscale images) was demonstrated by British inventor John Logie Baird

John Logie Baird

John Logie Baird FRSE was a Scottish engineer and inventor of the world's first practical, publicly demonstrated television system, and also the world's first fully electronic colour television tube...

on January 26, 1926, at his laboratory in London. Unlike later electronic systems with several hundred lines of resolution, Baird's vertically scanned image, using a scanning disk embedded with a double spiral of lenses, had only 30 lines, just enough to reproduce a recognizable human face.

Ulises Armand Sanabria

Ulises Armand Sanabria

Ulises Armand Sanabria was born in southern Chicago of Puerto Rican and French-American parents.-Career:...

was the builder and engineer of WCFL

WCFL (AM)

WCFL was the callsign of a commercial radio station in Chicago, Illinois, USA. It was owned by the Chicago Federation of Labor, hence its call letters. The station is now known as WMVP. Its transmitter is located in Downers Grove and is still in use by WMVP...

, the first mechanical television station to go on the air in Chicago

Chicago

Chicago is the largest city in the US state of Illinois. With nearly 2.7 million residents, it is the most populous city in the Midwestern United States and the third most populous in the US, after New York City and Los Angeles...

on June 12, 1928. By sending the sound signal to station WIBO and the video signal on WCFL, he was the first to transmit sound and picture simultaneously on the same wave band on May 19, 1929. Several US universities established and maintained mechanical television stations from 1930 to 1939. (See External Links below for list of such stations US and Canada 1928-1939.)

Because only a limited number of holes could be made in the disks, and disks beyond a certain diameter became impractical, image resolution on mechanical television broadcasts was relatively low, ranging from about 30 lines up to 120 or so. Nevertheless, the image quality of 30-line transmissions steadily improved with technical advances, and by 1933 the UK broadcasts using the Baird system were remarkably clear. A few systems ranging into the 200-line region also went on the air. Two of these were the 180-line system that Compagnie des Compteurs (CDC) installed in Paris

Paris

Paris is the capital and largest city in France, situated on the river Seine, in northern France, at the heart of the Île-de-France region...

in 1935, and the 180-line system that Peck Television started in 1935 at station VE9AK in Montreal

Montreal

Montreal is a city in Canada. It is the largest city in the province of Quebec, the second-largest city in Canada and the seventh largest in North America...

.

Instead of a Nipkow disk, mechanical television could also use several other technologies. Other arrangements often made use of a rotating drum, either with holes or with a series of mirror

Mirror

A mirror is an object that reflects light or sound in a way that preserves much of its original quality prior to its contact with the mirror. Some mirrors also filter out some wavelengths, while preserving other wavelengths in the reflection...

s on it.

Flying spot scanners

Another scanning method was the "flying spot." The flying spot developed as a remedy for the low sensitivity that photoelectric cells had at the time. A bright, narrow beam of light would shine through the holes of a Nipkow disk. This light would then illuminate the television subject, standing in a darkened studio.

Whipping back and forth and up and down, the spot of light would complete sixteen or more scans per second. The light would reflect back to not one, but a bank of photoelectric cells. The combined signals of these cells gave a strong picture. Like mechanical television itself, flying spot technology grew out of phototelegraphy (facsimile). This scanning method began in the 19th century.

The BBC television service used the flying spot method until 1935. German television used flying spot methods as late as 1938. This year was by far not the end of flying spot scanner technology. The German inventor Manfred von Ardenne

Manfred von Ardenne

Manfred von Ardenne was a German research and applied physicist and inventor. He took out approximately 600 patents in fields including electron microscopy, medical technology, nuclear technology, plasma physics, and radio and television technology...

designed a flying spot scanner with a CRT as the light source. In the 1950s, DuMont

DuMont Television Network

The DuMont Television Network, also known as the DuMont Network, DuMont, Du Mont, or Dumont was one of the world's pioneer commercial television networks, rivalling NBC for the distinction of being first overall. It began operation in the United States in 1946. It was owned by DuMont...

marketed Vitascan

Vitascan

Vitascan was an early color television camera system developed by American television equipment manufacturer DuMont Laboratories. Development began in 1949 and the product was released on an experimental basis in 1956...

, an entire flying-spot color studio system. Today, graphic scanners still use this scanning method. The flying spot method has two disadvantages:

Actors must perform in near darkness;
Flying spot cameras tend to work unreliably outdoors in daylight.

A note about outdoor telecasts with a flying spot scanner: In 1928, Ray Kell from the United States' General Electric

General Electric

General Electric Company , or GE, is an American multinational conglomerate corporation incorporated in Schenectady, New York and headquartered in Fairfield, Connecticut, United States...

proved that flying spot scanners could work outdoors. The scanning light source must be brighter than other incident illumination.

Kell was the engineer who ran a 24-line camera that telecast pictures of New York governor Al Smith

Al Smith

Alfred Emanuel Smith. , known in private and public life as Al Smith, was an American statesman who was elected the 42nd Governor of New York three times, and was the Democratic U.S. presidential candidate in 1928...

. Smith was accepting the Democratic nomination for presidency. As Smith stood outside the capital in Albany, Kell managed to send usable pictures to his associate Bedford at station WGY, which was broadcasting Smith's speech. The rehearsal went well, but then the real event began. The newsreel cameramen switched on their floodlights.

Unfortunately for Kell, his scanner only had a 1 kW lamp inside it. The floodlights threw much more light on Governor Smith. These floods simply overwhelmed Kell's image. In fact, the floods made the unscanned part of the image as bright as the scanned part. Kell's photocells couldn't pick up reflections off Smith from the AC scanning beam. Instead, the photocells only detected the flat, DC light from the floodlamps.

The effect is very similar to extreme overexposure in a still camera: The scene disappears, and the camera records a flat, bright light. Use the camera in favorable conditions, though, and the picture comes out fine. Similarly, Kell proved that outdoors in favorable conditions, his scanner worked fine.

Mechanical television with large pictures

A few mechanical TV systems could produce images several feet wide and of comparable quality to the cathode ray tube (CRT) televisions that were to follow. CRT technology at that time was limited to small, low-brightness screens. One such system was developed by Ulises Armand Sanabria

Ulises Armand Sanabria

Ulises Armand Sanabria was born in southern Chicago of Puerto Rican and French-American parents.-Career:...

in Chicago. By 1934, Sanabria demonstrated a projection system which had a 30-foot image.

Perhaps the best mechanical televisions of the 1930s used the Scophony

Scophony

Scophony was a sophisticated mechanical television system developed in Britain by Scophony Limited, which used mirrors mounted on high-speed rotating drums to project an image upon a screen....

system, which could produce images of more than 400 lines and display them on screens at least 9×12 feet (2.8×3.7 m) in size (at least a few models of this type were actually produced).

The Scophony system used multiple drums rotating at fairly high speed to create the images. One using a 441-line American

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

standard of the day had a small drum rotating at 39,690 rpm (a second slower drum moved at just a few hundred rpm). Today, DLP mechanical TV technology from Texas Instruments

Texas Instruments

Texas Instruments Inc. , widely known as TI, is an American company based in Dallas, Texas, United States, which develops and commercializes semiconductor and computer technology...

far outstrips the capabilities of the Scophony system.

Aspect ratios for different purposes

Some mechanical equipment scanned lines vertically rather than horizontally

Horizontal plane

In geometry, physics, astronomy, geography, and related sciences, a plane is said to be horizontal at a given point if it is perpendicular to the gradient of the gravity field at that point— in other words, if apparent gravity makes a plumb bob hang perpendicular to the plane at that point.In...

, as in modern TVs. An example of this method is the Baird 30-line system. Baird's British system created a picture in the shape of a very narrow, vertical rectangle.

This shape created a portrait

Portrait

thumb|250px|right|Portrait of [[Thomas Jefferson]] by [[Rembrandt Peale]], 1805. [[New-York Historical Society]].A portrait is a painting, photograph, sculpture, or other artistic representation of a person, in which the face and its expression is predominant. The intent is to display the likeness,...

image, instead of the landscape

Landscape

Landscape comprises the visible features of an area of land, including the physical elements of landforms such as mountains, hills, water bodies such as rivers, lakes, ponds and the sea, living elements of land cover including indigenous vegetation, human elements including different forms of...

orientation that is common today. The position of a framing mask before the Nipkow disk determines the scan line orientation. Placement of the framing mask at the left or right side of the disk gives vertical scan lines. Placement at the top or bottom of the disk gives horizontal scan lines.

Baird's earliest television images had very low definition. These images could only show one person clearly. For this reason, a vertical, portrait image made more sense to Baird than a horizontal, landscape image. Baird chose a shape three units wide by seven high. Actually this shape is only about half as wide as a traditional portrait. You can imagine this shape this way: A typical doorway also has the proportions three by seven.

Instead of entertainment television, Baird might have had point-to-point communication in mind. Another television system followed that reasoning. The 1927 system developed by Herbert E. Ives

Herbert E. Ives

Herbert Eugene Ives was a scientist and engineer who headed the development of facsimile and television systems at AT&T in the first half of the twentieth century. He was also a critic of the special theory of relativity, and attempted to disprove the theory by means of logical arguments and...

at AT&T's Bell Laboratories was a large-screen television system and the most advanced television of its day. The Ives 50-line system also produced a vertical "portrait

Portrait

" picture. Since AT&T intended to use television for telephony, the vertical shape was logical: phone calls are usually conversations between just two people. A picturephone system would depict one person on each side of the line.

Meanwhile, in the US, Germany and elsewhere, other inventors planned to use television for entertainment purposes. These inventors began with square or landscape pictures. (For example, consider the television systems of these men: Ernst Alexanderson

Ernst Alexanderson

Ernst Frederick Werner Alexanderson was a Swedish-American electrical engineer, who was a pioneer in radio and television development.-Background:...

, Frank Conrad

Frank Conrad

Frank Conrad was a radio broadcasting pioneer who worked as the Assistant Chief Engineer for the Westinghouse Electric Corporation in Pittsburgh, Pennsylvania,...

, Charles Francis Jenkins, William Peck and Ulises Armand Sanabria

Ulises Armand Sanabria

Ulises Armand Sanabria was born in southern Chicago of Puerto Rican and French-American parents.-Career:...

.) These inventors realized that television is about relationships between people. From the very beginning, these inventors allowed picture space for two-shots. Soon, images increased to 60 lines or more. The camera could easily photograph several people at once. Then even Baird switched his picture mask to a horizontal image. Baird's "zone television" is an early example of rethinking his extremely narrow screen format. For entertainment and most other purposes, even today, landscape remains the more practical shape.

Rise of electronic television

The advancement of all-electronic television (including image dissector

Video camera tube

In older video cameras, before the mid to late 1980s, a video camera tube or pickup tube was used instead of a charge-coupled device for converting an optical image into an electrical signal. Several types were in use from the 1930s to the 1980s...

s and other camera tubes and cathode ray tube

Cathode ray tube

The cathode ray tube is a vacuum tube containing an electron gun and a fluorescent screen used to view images. It has a means to accelerate and deflect the electron beam onto the fluorescent screen to create the images. The image may represent electrical waveforms , pictures , radar targets and...

s for the reproducer) marked the beginning of the end for mechanical systems as the dominant form of television. Mechanical TV usually only produced small images. It was the main type of TV until the 1930s.

All-electronic television, first demonstrated in September 1927 in San Francisco by Philo Farnsworth

Philo Farnsworth

Philo Taylor Farnsworth was an American inventor and television pioneer. Although he made many contributions that were crucial to the early development of all-electronic television, he is perhaps best known for inventing the first fully functional all-electronic image pickup device , the "image...

, and then publicly by Farnsworth at the Franklin Institute

Franklin Institute

The Franklin Institute is a museum in Philadelphia, Pennsylvania, and one of the oldest centers of science education and development in the United States, dating to 1824. The Institute also houses the Benjamin Franklin National Memorial.-History:On February 5, 1824, Samuel Vaughn Merrick and...

in Philadelphia in 1934, was rapidly overtaking mechanical television. Farnsworth's system was first used for broadcasting in 1936, reaching 400 to more than 600 lines with fast field scan rates, along with competing systems by Philco

Philco

Philco, the Philadelphia Storage Battery Company , was a pioneer in early battery, radio, and television production as well as former employer of Philo Farnsworth, inventor of cathode ray tube television...

and DuMont Laboratories

DuMont Laboratories

DuMont Laboratories was an American television equipment manufacturer. The company was founded in 1931, by inventor Allen B. DuMont. Among the company's developments were long-lasting cathode ray tubes that would be used for television. Another product out of the lab was a DuMont invention, the...

. The last mechanical television broadcasts ended in 1939 at stations run by a handful of public universities in the United States. In 1939, RCA paid Farnsworth $1 million for his patents after ten years of litigation, and RCA began demonstrating all-electronic television at the 1939 World's Fair in New York City

New York City

New York is the most populous city in the United States and the center of the New York Metropolitan Area, one of the most populous metropolitan areas in the world. New York exerts a significant impact upon global commerce, finance, media, art, fashion, research, technology, education, and...

Color mechanical television

Mechanical television returned to the United States as a method of painting colors over a monochrome CRT. The CBS color television

Color television

Color television is part of the history of television, the technology of television and practices associated with television's transmission of moving images in color video....

system of Peter Goldmark

Peter Carl Goldmark

Peter Carl Goldmark was a German-Hungarian engineer who, during his time with Columbia Records, was instrumental in developing the long-playing microgroove 33-1/3 rpm vinyl phonograph disc, the standard for incorporating multiple or lengthy recorded works on a single disc for two generations...

used such technology in 1940. John Baird's 1928 color television experiments had inspired Goldmark's more advanced field-sequential color system

Field-sequential color system

A field-sequential color system is a color television system in which the primary color information is transmitted in successive images, and which relies on the human vision system to fuse the successive images into a color picture. One field-sequential system was developed by Dr. Peter Goldmark...

. In Goldmark's system, stations transmit color saturation values electronically. Yet mechanical methods also come into play. At the transmitting camera, a mechanical disc filters hues (colors) from reflected studio lighting. At the receiver, a synchronized disc paints the same hues over the CRT. As the viewer watches pictures through the color disc, the pictures appear in full color.

Of course, simultaneous color systems superseded the CBS-Goldmark system. Yet mechanical color methods continued to find uses. Early color sets were very expensive, over $1,000 in the money of the time. Inexpensive adapters allowed owners of black-and-white, NTSC

NTSC

NTSC, named for the National Television System Committee, is the analog television system that is used in most of North America, most of South America , Burma, South Korea, Taiwan, Japan, the Philippines, and some Pacific island nations and territories .Most countries using the NTSC standard, as...

television sets to receive color telecasts. The most prominent of these adapters is Col-R-Tel, a 1955 NTSC to field-sequential converter. This system operates at NTSC scanning rates, but uses a disc like the obsolete CBS system had. The disc converts the black-and-white set to a field-sequential set. Meanwhile, Col-R-Tel electronics recover NTSC color signals and sequence them for disc reproduction. The electronics also synchronize the disc to the NTSC system. In Col-R-Tel, the electronics provide the saturation values (chroma). These electronics cause chroma values to superimpose over brightness (luminance)changes of the picture. The disc paints the hues (color) over the picture.

A few years after Col-R-Tel, Apollo moon missions also adopted field-sequential techniques. The lunar color cameras all had color wheels. These Westinghouse and later RCA

RCA

RCA Corporation, founded as the Radio Corporation of America, was an American electronics company in existence from 1919 to 1986. The RCA trademark is currently owned by the French conglomerate Technicolor SA through RCA Trademark Management S.A., a company owned by Technicolor...

cameras sent field-sequential color television pictures to earth. The earth receiving stations included mechanical equipment that converted these pictures to standard television formats.

Today, some Digital Light Processing (DLP) projectors still use color filter wheels.

Recording

In the days of commercial mechanical television transmissions, a system of recording images (but not sound) was developed, using a modified gramophone recorder. Marketed as "Phonovision

Phonovision

Phonovision is a proof of concept format and experiment for recording a mechanical television signal on phonograph records. The format was developed in the late 1920s in London by Scottish television pioneer John Logie Baird...

", this system, which was never fully perfected, proved to be complicated to use as well as quite expensive, yet managed to preserve a number of early broadcast images that would otherwise have been lost. Scottish computer engineer Donald F. McLean has painstakingly reconstructed the analogue playback technology required to view these recordings, and has given lectures and presentations on his collection of mechanical television recordings made between 1925 and 1933.

Among the discs in Dr. McLean's collection are a number of test recordings made by television pioneer John Logie Baird

John Logie Baird

himself. One disc, dated "28th March 1928" and marked with the title "Miss Pounsford", shows several minutes of a woman's face in what appears to be very animated conversation. In 1993, the woman was identified by relatives as Mabel Pounsford, and her brief appearance on the disc is one of the earliest known video recordings of a human being.

Recent uses of mechanical television

Since the 1970s, some amateur radio

Amateur radio

Amateur radio is the use of designated radio frequency spectrum for purposes of private recreation, non-commercial exchange of messages, wireless experimentation, self-training, and emergency communication...

enthusiasts have experimented with mechanical systems. The early light source of a neon lamp

Neon lamp

A neon lamp is a miniature gas discharge lamp that typically contains neon gas at a low pressure in a glass capsule. Only a thin region adjacent to the electrodes glows in these lamps, which distinguishes them from the much longer and brighter neon tubes used for signage...

has now been replaced with super-bright LED

Light-emitting diode

A light-emitting diode is a semiconductor light source. LEDs are used as indicator lamps in many devices and are increasingly used for other lighting...

s. There is some interest in creating these systems for narrow-bandwidth television

Narrow-bandwidth television

Narrow-bandwidth television is a type of television designed to fit into a low-bandwidth channel, in the extreme case using amateur radio voice frequency channels that only range up to a few kilohertz...

, which would allow a small moving image to fit into a channel less than 40 kHz wide (modern TV systems usually have a channel about 6 MHz wide, 150 times larger). Also associated with this is slow-scan TV

Slow-scan television

Slow-scan television is a picture transmission method used mainly by amateur radio operators, to transmit and receive static pictures via radio in monochrome or color.A technical term for SSTV is narrowband television...

, although that typically uses electronic systems.

The re-emergence of mechanical TV techniques

Today, a mechanical system of a sort has seen moderate popularity. Digital Light Processing (DLP) projectors use an array of tiny (16 μm²) electrostatically

Electrostatics

Electrostatics is the branch of physics that deals with the phenomena and properties of stationary or slow-moving electric charges....

-actuated mirrors selectively reflecting a light source to create an image. Many low-end DLP systems also use a color wheel

Color wheel

A color wheel or color circle is an abstract illustrative organization of color hues around a circle that shows relationships between primary colors, secondary colors, complementary colors, etc....

to provide a sequential color image, a common feature of many early color television systems before the shadow mask

Shadow mask

The shadow mask is one of two major technologies used to manufacture cathode ray tube televisions and computer displays that produce color images. The other approach is aperture grille, better known by its trade name, Trinitron. All early color televisions and the majority of CRT computer monitors...

CRT

Cathode ray tube

provided a practical method for producing a simultaneous color image.

Another place where high-quality imagery is produced by opto-mechanics is the laser printer

Laser printer

A laser printer is a common type of computer printer that rapidly produces high quality text and graphics on plain paper. As with digital photocopiers and multifunction printers , laser printers employ a xerographic printing process, but differ from analog photocopiers in that the image is produced...

, where a small rotating mirror is used to deflect a modulated laser beam in one axis while the motion of the photoconductor provides the motion in the other axis. A modification of such a system using high power lasers is used in laser video projectors, with resolutions as high as 1024 lines and each line containing >1500 points. Such systems produce, arguably, the best quality video images. They are used, for instance, in planetarium

Planetarium

A planetarium is a theatre built primarily for presenting educational and entertaining shows about astronomy and the night sky, or for training in celestial navigation...

s.

The closest modern systems to the original mechanical scan camera is the long wave infrared

Infrared

Infrared light is electromagnetic radiation with a wavelength longer than that of visible light, measured from the nominal edge of visible red light at 0.74 micrometres , and extending conventionally to 300 µm...

cameras used in military applications such as giving fighter pilots night vision. These cameras use a high sensitivity infrared photo receptor (usually cooled to increase sensitivity), but instead of disks of lenses, these systems use rotating prisms to provide a 525 or 625 line standard video output. The optical parts are made from germanium, because glass is opaque at the wavelengths involved. These cameras have found a new role in sporting events where they are able to show (for example) where a ball has struck a bat.

Laser lighting display

Laser lighting display

A laser lighting display or laser light show involves the use of laser light to entertain an audience. A laser light show may consist only of projected laser beams set to music, or may accompany another form of entertainment, typically a dance concert or other musical performance.Laser light is...

techniques are combined with computer emulation

Emulator

In computing, an emulator is hardware or software or both that duplicates the functions of a first computer system in a different second computer system, so that the behavior of the second system closely resembles the behavior of the first system...

in the LaserMAME project. It is a vector

Vector graphics

Vector graphics is the use of geometrical primitives such as points, lines, curves, and shapes or polygon, which are all based on mathematical expressions, to represent images in computer graphics...

-based system, unlike the raster

Raster scan

A raster scan, or raster scanning, is the rectangular pattern of image capture and reconstruction in television. By analogy, the term is used for raster graphics, the pattern of image storage and transmission used in most computer bitmap image systems...

displays thus-far described. Laser

Laser

A laser is a device that emits light through a process of optical amplification based on the stimulated emission of photons. The term "laser" originated as an acronym for Light Amplification by Stimulated Emission of Radiation...

light reflected from computer-controlled mirrors traces out images generated by classic arcade software which is executed by a specially modified version of the MAME

MAME

MAME is an emulator application designed to recreate the hardware of arcade game systems in software on modern personal computers and other platforms. The intention is to preserve gaming history by preventing vintage games from being lost or forgotten...

emulation software.

External links

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