Rigid circular plate of either metal or plastic used to record video and audio signals for playback. It resembles a phonograph record and can be played on a machine attached to a conventional television receiver. There are two major classes of videodiscs, magnetic and nonmagnetic. Magnetic videodiscs have an oxide-coated surface onto which input signals are recorded as magnetic patterns in spiral tracks. Nonmagnetic videodiscs use either a mechanical recording system analogous to that used in phonograph records, or optical technology that uses a laser to read data coded as a sequence of pits on the disc. The most common type of videodisc today is the DVD.
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The Laserdisc (LD) is an obsolete home video disc format, and was the first commercial optical disc storage medium. Initially marketed as Discovision in 1978, the technology was licensed and sold as Reflective Optical Videodisc, Laser Videodisc, Laservision, Disco-Vision, DiscoVision, and MCA DiscoVision until Pioneer Electronics purchased the majority stake in the format and marketed LaserDisc in the mid to late 1980s.
While technologically superior to the then rival VHS and Betamax systems, the laserdisc never obtained more than a niche market with videophiles in America. In Japan, the format was better supported and thus more prevalent. In Europe, it remained largely an obscure format. The technology and concepts proved with the Laserdisc would become the forerunner to Compact Discs and DVDs.
The first Laserdisc title marketed in North America was the MCA DiscoVision release of Jaws in 1978. The last two titles released in North America were Paramount's Sleepy Hollow and Bringing Out the Dead in 2000. A dozen or so more titles continued to be released in Japan until the end of 2001. The last Japanese-released Laserdisc-format movie title was Tokyo Raiders.
It was estimated that in 1998, Laserdisc players were in approximately 2% of US households (roughly two million). By comparison, in 1999, players were in 10% of Japanese households. Laserdisc has been completely replaced by DVD in the North American retail marketplace, as neither players nor software are now produced there. Laserdisc has retained some popularity among American collectors and, to a greater degree, in Japan, where the format was better supported and more prevalent during its life. In Europe, the Laserdisc has always remained an obscure format. The format was, however, chosen by the British Broadcasting Corporation(BBC) for the BBC Domesday Project in the mid-1980s, a school-based project to commemorate 900 years since the original Domesday Book in England.
Since digital encoding and compression schemes were either unavailable or impractical in 1978, three encoding formats based on the rotation speed were used:
As Pioneer introduced Digital Audio to Laserdisc in 1985, they further refined the CAA format. CAA55 was introduced in 1985 with a total playback capacity of 55 minutes 5 seconds, and was necessary to resolve technical issues with the inclusion of Digital Audio. Several titles released between 1985 and 1987 were analog audio only due to the length of the title and the desire to keep the film on 1 disc (e.g., "Back to the Future"). By 1987, Pioneer had overcome the technical challenges and was able to once again encode in CAA60—allowing a total of 60 minutes, 5 seconds. Pioneer further refined CAA, offering CAA45—encoding 45 minutes of material, but filling the entire playback surface of the side. Used on only a handful of titles, CAA65 offered 65 minutes 5 seconds of playback time. The final variant of CAA is CAA70, which could accommodate 70 minutes of playback time. There are not any known uses of this format on the consumer market.
All of these timing parameters are based on the NTSC standard of 30fps. The PAL and SECAM standards of 25fps increases the playback capacity of all the various formats by 20%.
The two FM audio channels occupied the disc spectrum at 2.3 and 2.8 MHz on NTSC formatted discs and each channel had a 100 kHz FM deviation. The FM audio carrier frequencies were chosen to minimize their visibility in the video image, so that even with a poorly mastered disc, audio carrier beats in the video will be at least -35db down, and thus, invisible. Due to the frequencies chosen, the 2.8MHz audio carrier (Right Channel) and the lower edge of the chroma signal are very close together and if filters are not carefully set during mastering, there can be interference between the two. In addition, high audio levels combined with high chroma levels can cause mutual interference, leading to beats becoming visible in highly saturated areas of the image. To help deal with this, Pioneer decided to implement the CX Noise Reduction System on the analog tracks. By reducing the dynamic range and peak levels of the audio signals stored on the disc, filtering requirements were relaxed and visible beats greatly reduced or eliminated. The CX system gives a total NR effect of 20db, but in the interest of better compatibility for non-decoded playback, Pioneer reduced this to only 14db of noise reduction (the RCA CED system used the 'original' 20db CX system). This also relaxed calibration tolerances in players and helped reduce audible pumping if the CX decoder wasn't calibrated correctly.
At least where the digital audio tracks were concerned, the sound quality was unsurpassed at the time, but the quality of the analog soundtracks varied greatly depending on the disc and, sometimes, the player. Many early and lower-end LD players had poor analog audio components, and many early discs had poorly mastered analog audio tracks, making digital soundtracks in any form most desirable to serious enthusiasts. Early DiscoVision and Laserdisc titles lacked the digital audio option, but many of those movies received digital sound in later re-issues by Universal, and the quality of analog audio tracks generally got far better as time went on. Many discs that had originally carried old analog stereo tracks received new Dolby Stereo and Dolby Surround tracks instead, often in addition to digital tracks, helping boost sound quality. Later analog discs also applied CX Noise Reduction, which improved the signal-noise ratio of their audio.
Both AC-3 and DTS surround audio were clumsily implemented on Laserdiscs, leading to some interesting player- and disc-dependent issues. A disc that included AC-3 audio forfeited the right analog audio channel to the modulated AC-3 stream. If the player did not have an AC-3 decoder available, the next most attractive playback option would be the digital Dolby Surround or stereo audio tracks. If either the player did not support digital audio tracks (common in older players), or the disc did not include digital audio tracks at all (uncommon for a disc which is mastered with an AC-3 track), the only remaining option was to fall back to a monophonic presentation of the left analog audio track. However, many older analog-only players not only failed to decode AC-3 streams, but weren't even aware of their potential existence. Such a player will happily play the analog audio tracks verbatim, resulting in garbage output in the right channel.
On a DTS disc, digital PCM audio is not available, so if a DTS decoder was also not available, the only option is to fall back to the analog Dolby Surround or stereo audio tracks. In some cases, the analog audio tracks were further made unavailable through replacement with supplementary audio such as isolated scores or audio commentary. This effectively reduced playback of a DTS disc on a non-DTS equipped system to mono audio—or in a handful of cases, no film soundtrack at all.
Only one 5.1 surround sound option existed on a given Laserdisc (either Dolby Digital or DTS), so if surround sound is desired, the disc must be matched to the capabilities of the playback equipment (LD Player and Receiver/Decoder) by the purchaser. A fully capable Laserdisc playback rig includes a newer Laserdisc player that is capable of playing digital tracks, has a digital optical output for digital PCM and DTS audio, is aware of AC-3 audio tracks, and has an AC-3 coaxial output; an external or internal AC-3 RF demodulator and AC-3 decoder; and a DTS decoder. Many A/V receivers combine the AC-3 decoder and DTS decoder logic, but an integrated AC-3 demodulator is rare both in Laserdisc players and in newer A/V receivers.
Most machines made were single-sided; players which required manually turning the disk over to play the other side. A number of players were made that were 'double-sided', in that the machine could automatically reverse the spin direction and move the pickup head to the other side of the disk. While Pioneer produced some industrial "jukeboxes" that held more than 50 discs, only one consumer player, the LD-W1, could hold more than a single disc - the W1 held two discs and could automatically change discs and sides by rotating the entire mechanism, including both the laser and turntable. Electrically, the LD-W1 was the internal circuitry of the Elite LD-S1 combined with the disc/side changing mechanism.
Many Laserdisc players manufactured from the late 1980s through the time of the format's death had both composite (red, white and yellow RCA type connectors) and S-Video outputs on the rear panel. When using the S-Video connection, the player would utilize its own internal comb filter, designed to help reduce picture noise by separating the luminance (brightness) and color parts of the signal, while using the composite outputs forced the player to rely on the comb filter of the display device. Although using the S-Video connection was often considered to yield superior results in the late 80s and early 1990s, most of today's mid and high level television sets contain better comb filters than the vast majority of players were equipped with. In these instances, where a player is being used with a more modern display, using the composite output and allowing the display device's internal comb filter to do the work may yield better results.
In 1996, the first model DVD/LD combi-player (and first Pioneer DVD player, for that matter) was the Pioneer DVL-9 released in Japan. The Pioneer Elite DVL-90, an updated version, followed by a similar, though supposedly lower-end model, the DVL-700, were released in 1997. Successors to this model include the Pioneer DVL-909, Pioneer DVL-919, and the Pioneer Elite DVL-91. Although the DVD/LD combi players offered competent LD performance, they paled in comparison to high end LD players such as the Pioneer Elite CLD-99 and the Pioneer Hi-Vision/MUSE HLD-X9.
The Pioneer DVL-909 lacks support for DTS output. However, a modification to the player can allow this player to support DTS streams on DTS discs, essentially turning the DVL-909 into a Pioneer Elite DVL-91.
The last model DVD/LD player was the Japanese only DVL-H9, but the older DVL-919 is still sold in the U.S. and appears on Pioneer's North American website. However, it has not been actively marketed since the late 1990s. The DVL-919 supports DTS output. The DVL-919's DVD section is unremarkable by modern standards, and does not support progressive scan (480p) even though it has component output. As noted above, the LD section, while competent, is inferior to earlier high end LD players. A few Pioneer dealers offer North American specification DVL-919s, and a unit purchased in April 2004 had a manufacture date of December 2003. Pioneer representatives reportedly state that the product is officially discontinued, and that warranty coverage for 919s will be based on the date of manufacture rather than on the date of sale.
The CLD-R7G, LD-S9 and HLD-X9 share a highly advanced comb filter, allowing them to offer a considerable advantage in picture quality over most other LD players when the S-Video connection is used. The comb filter present in these players is unique and is purportedly the finest comb filter ever used in consumer A/V gear: it is still currently in use in Mitsubishi's top-spec CRT rear-projection television sets (the Diamond and now defunct Platinum series sets) and Pioneer's Elite line of rear-projection televisions.
In addition to the advanced comb filter, the HLD-X9 contains a red-laser pickup, which significantly reduces crosstalk and picture-noise levels compared to players with the traditional infrared laser; it can also read through all but the worst cases of laser rot and surface wear. The HLD-X9 is, lastly, also a MUSE player, capable when properly equipped of playing back high definition Laserdiscs, called Hi-Vision or MUSE discs in Japan.
The HLD-X0 is Pioneer's original MUSE player, and is the player of choice for many enthusiasts despite the fact that it lacks the comb filter shared by the R7G, S9 and X9. It was entirely hand built from hand picked electronics and weighed a massive 36 kilograms. Many argue that the newer X9 was a more capable MUSE player but that the X0 had superior performance with standard NTSC discs. Nonetheless, the X9 remains the more popular of the two models, as it includes the newer comb filter and is a dual-side player, meaning that double sided discs don't need to be manually flipped over in order for both sides to be played.
Pioneer Electronics also entered the optical disc market in 1977 as a 50/50 joint-venture with MCA called Universal-Pioneer and manufacturing MCA designed industrial players under the MCA DiscoVision name (the PR-7800 and PR-7820). For the 1980 launch of the first Universal-Pioneer player, the VP-1000, the name became Laser Disc (with a 'rainbow' type logo joining the two words) and in 1981 the intercap was eliminated and "LaserDisc" became the final and common nickname for the format, although the official name was LaserVision. However, as Pioneer reminded numerous video magazines and stores in 1984, LaserDisc was a trademarked word, standing only for LaserVision products manufactured for sale by Pioneer Video or Pioneer Electronics. A 1984 Ray Charles ad for the LD-700 player bore the term "Pioneer LaserDisc brand videodisc player." From 1981 until the early 90's, all properly licensed discs carried the LaserVision name and logo, even Pioneer Artists titles.
During the early years, MCA also manufactured discs for other companies including Paramount, Disney and Warner Bros. Some of them added their own names to the disc jacket to signify that the movie was not owned by MCA. After Discovision Associates shut down in early 1982, Universal Studio's videodisc software label, called MCA Videodisc until 1984, began reissuing many DiscoVision titles. Sadly, quite a few, such as Battlestar Galactica and Jaws, were time-compressed versions of their CAV or CLV DiscoVision originals. The time-compressed CLV re-issue of JAWS no longer had the original soundtrack, having had some incidental background music replaced for the videodisc version due to licensing cost (the music wouldn't be available until the THX LaserDisc box set was released in 1995). One Universal/Columbia co-production issued by MCA DiscoVision in both CAV and CLV versions, The Electric Horseman, is still not available in any other home video format with its original score intact - even the most recent DVD release has had substantial music replacements of both instrumental score and Willie Nelson's songs.
An interesting note about the 7820 is that it is the ONLY player ever sold to either the industrial or consumer market that was 100% designed and engineered by the technicians at MCA Disco-Vision and contained all of their preferred design approaches, such as playing the disc with the laser on top (instead of underneath) and moving the disc radially to provide tracking instead of moving the laser radially. MCA engineers designed the player at the DiscoVision labs in Torrance, CA and Universal-Pioneer mass produced it in Japan. The 7820 was such a high quality player that MCA themselves used it at their DiscoVision disc pressing plant in Carson, CA for quality control checks of both master discs and finished sets - unfortunately, this caused problems because the 7820 could (with ease!) play discs that the poorly designed and quite primitive consumer player, the Magnavox VH-8000, simply couldn't cope with. In 1980, Discovision Associates released a factory update (it could also be retrofitted to existing 7820's) that reduced disc search times to less than 3 seconds - and also added the ability to jump up to 99 tracks during vertical blanking, giving essentially, 'instant' searches. An external computer interface box was also made available at the same time which contained additional memory that increased the total size of a disc-based computer program the 7820 could store and execute to 256k. The 7820 was the first LD player to use solid-state tangential tracking - instead of a tangential tracking mirror, the 7820 used an electronic CCD delay line to provide tangential tracking corrections, giving the player superb color quality. It wasn't until 1985/6 that the tangential mirror began to be replaced by electronic correction, first by Yamaha in their first consumer LD player, and eventually, by Pioneer themselves.
MCA DiscoVision had no suggested retail price for the PR-7820 - it varied depending on the number bought - from a high of $3,500 for a single unit to as low as $2,200 if more than 1000 were bought at once. Fully functional 7820's are "NOT" easily available on eBay and are nearly impossible to find in fully functional condition. Because they are so heavy (and made of steel!), shipping is a major hassle and expense.
Moreover, because the discs are read optically instead of magnetically, no physical contact needs to be made between the player and the disc, except for the player's clamp that holds the disc at its center as it is spun and read. As a result, playback does not wear the information-bearing part of the discs, and properly manufactured LDs will theoretically last beyond one's lifetime (however, see Laser rot, below). By contrast, a VHS tape holds all of its picture and sound information on the tape in a magnetic coating which is in contact with the spinning heads on the head drum, causing progressive wear with each use. Also, the tape is thin and delicate, and it is easy for a player mechanism (especially on a low quality or malfunctioning model) to mishandle the tape and damage it by creasing it, frilling (stretching) its edges, or even breaking it.
Despite the apparent advantages over competing technology at the time (namely VHS), the format was not without its flaws. The discs were 12" in diameter, heavy, cumbersome, easier to damage when handling than a VHS cassette, and manufacturers did not market LD units with recording capabilities to consumers. Also, because of their size, greater mechanical effort was required to spin the discs at the proper speed, resulting in much more noise generated than other media.
In addition, perfect still frames and random access to individual still frames were limited only to the more expensive CAV discs, which only had a playing time of approximately 30 minutes per side. In later years, Pioneer and other manufacturers overcame this limitation by incorporating a digital memory buffer, which "grabbed" a single frame from a CLV title.
Despite their large physical size, the space-consuming analog video signal of a Laserdisc limited playback duration to 30 (CAV) or 60 minutes (CLV) per side because of their refusal to reduce line count for increased playtime. After one side was finished playing, a disc would have to be flipped over in order to continue watching the film, and many films required two discs or more. Many players, especially units built after the mid-1980s, could "flip" discs automatically by rotating the optical pickup to the other side of the disc, but this was accompanied by a pause in the movie during the side change. If the movie was longer than what could be stored on 2 sides of a single disc, manually swapping to a second disc would be necessary at some point during the film. One exception to this rule is the Pioneer LD-W1, which had two disc platters.
Later optical standards have been known to suffer similar problems, including a notorious batch of defective CDs manufactured by Philips-DuPont Optical in Europe during the early 1990s.
Coincidentally, the Laserdisc movie that has the most reported laser rot is the film Eraser (1996), as noted by the contributors of LaserDisc Database. The discs for this title were replicated by Sony Digital Audio Disc Corporation, U.S., in Terre Haute, Indiana.
Laserdisc is a composite video format: the luminance (black and white) and chrominance (colour) information are transmitted in one signal and it is the responsibility of the receiver to separate them. While good comb filters can do so adequately, these two signals cannot be completely separated. On DVDs, data is stored in the form of blocks which make up each independent frame. The signal produced is dependent on the equipment used to master the disc. Signals range from composite and split, to YUV and RGB. Dependent upon which format used this can result in far higher fidelity, particularly at strong colour borders or regions of high detail (particularly if there is moderate movement in the picture) and low-contrast details like skin tones, where comb filters almost inevitably smudge some detail.
Compared to the entirely digital DVD, Laserdiscs use only analog video. As the Laserdisc format is not digitally encoded and does not make use of compression techniques, it is immune from video macroblocking (most visible as blockiness during high motion sequences) or contrast banding (subtle visible lines in gradient areas, such as skies or light casts from spotlights) that can be caused by the MPEG-2 encoding process as video is prepared for DVD. However, proprietary human-assisted encoders manually operated by specialist experts can vastly reduce the incidence of artifacts.
DVDs almost exclusively use compressed audio formats such as Dolby Digital and DTS which offer multichannel sound. Most Laserdiscs were encoded with stereo (often Dolby Surround) CD quality audio 16bit/44kHz tracks as well as analog audio tracks. Many later release Laserdiscs included Dolby Digital and DTS audio tracks but at slightly lower bitrates than DVD.
Given the analog nature of Laserdiscs, without any forms of checksum or error correction, slight dust and scratches cause various problems that could affect video quality. Wearout and/or calibration drift on the playback hardware also play a role in degrading video quality, audio quality, and tracking accuracy. In contrast, the DVD format's digital nature and error correction ensures that the signal from a damaged disc will remain identical to that from a perfect disc right up until read errors become so bad as to prevent the disc from producing any usable data.
In the beginning, another advantage of LD was that you could skim over damaged spots, while a DVD would become unusable. Some newer DVD players feature a repair+skip algorithm, which alleviates this problem by continuing to play the disc, filling in unreadable areas of the picture with blank space or a frozen frame of the last readable image/sound. The success of this feature depends a lot upon the amount of damage. LD players, when working in full analog, recover from such errors faster than DVD players. Direct comparison is, however, almost impossible due to the differences between the two media. A 1" scratch on a DVD will probably cause more problems than a 1" scratch on an LD, but a fingerprint taking up, say, 1% of the area of a DVD would almost certainly cause fewer problems than a similar mark covering 1% of the surface of an LD.
Laserdisc players sometimes suffered a problem known as "crosstalk" on extended play discs, usually with equipment requiring service of the laser optical pickup assembly when this occurs. However, the problem with crosstalk may also occur with poorly manufactured CLV Laserdiscs or with discs that are excessively warped. The issue comes up when the optical pickup inside the player accidentally picks up the encoded video information from a track adjacent to where it was reading on the disc. The added information shows up as distortion in the picture, looking reminiscent of and referred to as "barber poles". Some players were better at compensating for and/or avoiding crosstalk entirely than others, provided that the cause of crosstalk was the disc and not the player. There is no crosstalk distortion on CAV standard play Laserdiscs as the rotational speed never varies, but, if the player calibration is out of order or if the CAV disc is faulty, other problems affecting tracking accuracy could occur, such as "laser lock", where the player reads the same track and, thus, the same two fields for one frame over and over again, causing the picture to freeze as if in pause.
On most television sets a given DVD player will produce a picture that is visually indistinguishable from other units, and quality differences between players only becomes easily apparent with higher-end equipment due to some post-processing of the MPEG-2 stream. In contrast, Laserdisc playback quality is highly dependent on hardware decoder quality (as with any analog format). Major variances in picture quality could appear between different makes and models of LD players, even when tested on a low to mid-range television. This had long lasting ramifications, as the pricing for high end players has remained comparably high (anywhere from US$200 to well over $1,000), while older and less desirable players can be purchased in working condition for as little as $25.
Laserdisc players were known to provide the operator with a great degree of control over the playback process. Unlike many DVD players, the operator is immediately tied to the transport mechanism: pause, fast-forward, and fast-reverse commands are always accepted. There were no "User Prohibited Options" where content protection code instructs the player to refuse commands to skip a specific part (such as fast forwarding through an FBI warning). However, some DVD players, particularly in the higher-end units, have the ability to ignore the blocking code and play the video without restrictions. With CAV laserdiscs the user can access each individual frame of a video; a feature not common among DVD players. However, Some DVD players have cache features which stores a certain amount of the video in RAM which allows the player to index a DVD as quickly as an LD, even down to the frame in some players.
Some of the Arguments
While Dolby Digital and DTS offer multichannel sound, many Laserdisc enthusiasts claim that the uncompressed PCM tracks can often outperform the respective DVDs of a title in richness and depth (and, because of the ways in which 5.1 tracks are often mastered, in dimension as well). One important factor in newer DVD releases' small advancement over Laserdiscs is their opting for 16bit/44kHz sound in lieu of the DVD standard's little-known 24bit/96kHz capabilities.
Some Laserdisc proponents believe analog laserdisc is theoretically capable of higher quality than the lossy quality of DVD. Early DVD demo discs often had compression or encoding problems, lending additional support to such claims at the time. However, "LD-perfection" is rarely achieved in practice. Only the best LDs in the best playback systems exhibit such superior quality in comparison to the newer DVDs. Proponents of Laserdisc argue that Laserdisc maintains a "smoother", more "film-like" image while DVD still looks slightly more artificial. This is similar to the CD versus LP sound quality debates common in the audiophile community.
This is a list of modern-day, digital-type measurements (and traditional, analog horizontal resolutions in TV lines per picture height) for various media. The list only includes popular formats, not rare formats, and all values are approximate (rounded to the nearest 10), since the actual quality can vary machine-to-machine or tape-to-tape. For PAL media, replace 480 with 576 and 240 with 288. For ease-of-comparison all values are for the NTSC system, and listed in ascending order from lowest quality to highest quality.
The format also became quite popular in Hong Kong during the 1990s before the introduction of VCDs and DVD; although people rarely bought the discs, high rental activity helped the video rental business in the city grow larger than it had ever been previously.
Despite the mild popularity, manufacturers refused to market recordable Laserdisc devices on the consumer market, even though the competing VCR devices could record onto cassette, which hurt sales worldwide. The inconvenient disc size, the high cost of both the players and the media and the inability to record onto the discs combined to take a serious toll on sales, and contributed to the format's mediocre adoption figures.
Although the Laserdisc format has been supplanted by DVD, many LDs are still highly coveted by movie enthusiasts. This is largely because there are many films that are still only available on LD and many other LD releases contain supplemental material not available on subsequent DVD versions of those films.
LD players are also sometimes found in contemporary North American high school and college physics classrooms, in order to play a disc of the Physics: Cinema Classics series of mid-20th century Encyclopædia Britannica films reproducing classic experiments in the field which are difficult or impossible to replicate in the laboratories in educational settings. These films have now been released on DVD.
Apple's HyperCard scripting language provided Macintosh computer users with a means to design databases of slides, animation, video and sounds from Laserdiscs and then to create interfaces for users to play specific content from the disc. User-created "stacks" were shared and were especially popular in education where teacher-generated stacks were used to access discs ranging from art collections to basic biological processes. Commercially available stacks were also popular with the Voyager company being possibly the most successful distributor.
Commodore International's 1992 multimedia presentation system for the Amiga, AmigaVision, included device drivers for controlling a number of Laserdisc players through a serial port. Coupled with the Amiga's ability to use a Genlock, this allowed for the Laserdisc video to be overlaid with computer graphics and integrated into presentations and multimedia displays, years before such practice was commonplace.
Pioneer also made computer-controlled units such as the LD-V2000. It had a back-panel RS-232 serial connection through a 5-pin DIN connector, and no front-panel controls except Open/Close. (The disc would be played automatically upon insertion.)
Under contract from the U.S. Military, Matrox produced a combination computer laserdisc player for instructional purposes. The computer was a 286, the laserdisc player only capable of reading the analog audio tracks. Together they weighed 43 pounds and sturdy handles were provided in case 2 people were required to lift the unit. The computer controlled the player via a 25-pin serial port at the back of the player and a ribbon cable connected to a proprietary port on the motherboard. Many of these were sold as surplus by the military during the 90s, often without the controller software. It is nevertheless possible to control the unit by removing the ribbon cable and connecting a serial cable directly from the computer's serial port to the port on the laserdisc player.
In 1991, several manufacturers announced specifications for what would become known as MUSE Laserdisc, representing a span of almost 15 years until the feats of this HD analog optical disc system would finally be duplicated digitally by HD DVD and Blu-ray. Encoded using NHK's MUSE "Hi-Vision" analogue TV system, MUSE discs would operate like standard Laserdiscs but would contain high-definition 1125-line (1035 visible lines) video with a 5:3 aspect ratio. The MUSE players were also capable of playing standard NTSC format discs and are superior in performance to non-MUSE players even with these NTSC discs. The MUSE-capable players had several noteworthy advantages over standard Laserdisc players, including a red laser with a much narrower wavelength than the lasers found in standard players. The red laser was capable of reading through disc defects such as scratches and even mild disc-rot that would cause most other players to stop, stutter or drop-out. Crosstalk was not an issue with MUSE discs, and the narrow wavelength of the laser allowed for the virtual elimination of crosstalk with normal discs.
In order to view MUSE encoded discs, it was necessary to have a MUSE decoder in addition to a compatible player. There are televisions with MUSE decoding built-in and set top tuners with decoders that can provide the proper MUSE input. Equipment prices were high, especially for early HDTVs which generally eclipsed US$10,000, and even in Japan the market for MUSE was tiny. Players and discs were never officially sold in North America, although several distributors imported MUSE discs along with other import titles. Terminator 2: Judgement Day, Lawrence of Arabia, A League of Their Own, Bugsy, Close Encounters of the Third Kind, Bram Stoker's Dracula and Chaplin were among the theatrical releases available on MUSE LDs. Several documentaries, including one about Formula One at Japan's Suzuka Circuit were also released.
The most common size of Laserdisc was 30 cm (12 inches). These approximated the size of LP vinyl records. These discs allowed for 30 minutes per side (CAV) or 60 minutes per side (CLV). The vast majority of programming for the Laserdisc format was produced on these discs.
20 cm (8 inches) Laserdiscs were also published. These "EP"-sized LDs allowed for 20 minutes per side (CLV). They are much rarer than the full-size LDs, especially in North America. These discs were often used for music video compilations (e.g., Bon Jovi's "Breakout", Bananarama's "Video Singles" or T'Pau's "View From A Bridge").
There were also 12 cm (5 inches) "single"-style discs produced that were playable on Laserdisc players. These were referred to as CD Video (CD-V) discs, and Video Single Discs (VSD). A CD-V carried up to 5 minutes of analog Laserdisc-type video content (usually a music video), as well as up to 20 minutes of digital audio CD tracks. The original 1989 release of David Bowie's restrospective Sound and Vision CD box set prominently featured a CD-V video of Ashes To Ashes, and standalone promo CD-V's featured the video, plus 3 audio tracks: John, I'm Only Dancing, Changes and The Supermen.
CD-Vs are not to be confused with Video CDs (which are all-digital and can only be played on VCD players, DVD players, CD-i players, computers, and later-model Laserdisc players (such as the DVL series from Pioneer that can also play DVDs). CD-Vs can only be played back on Laserdisc players with CD-V capability. VSDs were the same as CD-Vs, but without the audio CD tracks. CD-Vs were somewhat popular for a brief time worldwide, but soon faded from view. VSDs were popular only in Japan and other parts of Asia, and were never really introduced to the rest of the world.
There were no titles available in the US except for promotional purposes. Upon purchase of a Toshiba 16:9 television viewers had the option of selecting a number of Warner Brothers 16:9 films. Titles include Unforgiven, Grumpy Old Men, The Fugitive, and Free Willy. The Japanese lineup of titles was different. A series of releases under the banner "SQUEEZE LD" from Pioneer of mostly Carolco titles included Basic Instinct, Stargate, Terminator 2: Judgment Day, Showgirls, Cutthroat Island, and Cliffhanger. Oddly enough Terminator 2 was released twice in Squeeze LD, the second release being THX certified and a notable improvement over the first.
Another type of video media, CRVdisc, or "Component Recordable Video Disc" were available for a short time, mostly to professionals. Developed by Sony, CRVdiscs resemble early PC CD-ROM caddies with a disc inside resembling a full sized LD. CRVdiscs were blank, write-once, read-many media that could be recorded once on each side. CRVdiscs were used largely for backup storage in professional/commercial applications.
Another form of recordable Laserdisc that is completely playback-compatible with the Laserdisc format (unlike CRVdisc with its caddy enclosure) is the RLV, or Recordable LaserVision disc. It was developed and first marketed by the Optical Disc Corporation (ODC, now ODC Nimbus) in 1984. RLV discs, like CRVdisc, are also a WORM technology, and function exactly like a CD-R disc. RLV discs look almost exactly like standard Laserdiscs, and can play in any standard Laserdisc player after they've been recorded. The only difference an RLV disc has over regular factory-pressed Laserdiscs is their reflective purple-violet (or blue with some RLV discs) color resulting from the dye embedded in the reflective layer of the disc to make it recordable, as opposed to the silver mirror appearance of regular LDs. The purplish color of RLVs is very similar to some DVD-R and DVD+R discs. RLVs were popular for making short-run quantities of Laserdiscs for specialized applications such as interactive kiosks and flight simulators.
In spite of nonrecordability being commonly regarded as the primary weakness of the Laserdisc format, these recordable LD systems were never marketed toward the general public, and are so poorly known as to create the misconception that a home recording system for Laserdiscs is impossible.