TOSLINK: Difference between revisions

'''TOSLINK''' (from "'''Toshiba Link'''") is a standardized optical fiber connector system used for digital audio transmission. The most common application is carrying [[S/PDIF (optical)|S/PDIF]] digital audio signals between consumer audio and video equipment via pulses of visible red light through a fiber optic cable. The generic standard name is '''EIAJ optical''', while "TOSLINK" is a registered trademark of Toshiba.<ref name="wp-toslink">[https://en.wikipedia.org/wiki/TOSLINK "TOSLINK"], Wikipedia.</ref>

== History ==

Toshiba developed TOSLINK in 1983 to connect their CD players to their receivers for PCM digital audio streams. The system was adopted alongside the Sony/Philips Digital Interface (S/PDIF) standard, which had been created as part of the compact disc specification jointly proposed by Philips and Sony in 1980.<ref name="wp-toslink" /><ref name="audioholics">[https://www.audioholics.com/audio-video-cables/toslink-interconnect-history-basics "TOSLINK Interconnect History & Basics"], Audioholics.</ref>

 

 

 

The standard TOSLINK connector uses a rectangular plug conforming to the EIAJ/JEITA RC-5720 standard (also JIS C5974-1993 F05). The connector features a distinctive square-shaped body with a small protruding optical lens, typically covered by a hinged or removable dust cap when not in use.<ref name="wp-toslink" />

 

 

 

== Cable Types ==

 

 

* '''Plastic optical fiber (POF)''' — the most common and least expensive type, using a 1 mm plastic core. Effective range is limited to roughly 5–10 meters due to high signal attenuation.<ref name="wp-toslink" />

* '''Multistrand plastic fiber''' — higher quality than single-strand POF, offering improved flexibility and somewhat lower attenuation.

 

All TOSLINK cables are fragile compared to copper cables and can be temporarily or permanently damaged if sharply bent, stepped on, or pinched.

 

 

* '''Mini-TOSLINK''' — a miniaturized optical connector roughly the same size and shape as a 3.5 mm stereo minijack. Used on laptops (particularly Apple MacBooks), portable audio equipment, and other space-constrained devices. Adapters between full-size TOSLINK and Mini-TOSLINK are widely available. Some devices feature combined 3.5 mm / Mini-TOSLINK sockets that accept either plug type.<ref name="wp-toslink" />

 

 

* '''PCM stereo''' (2 channels, up to 24-bit/192 kHz) — the most common use

* '''DTS''' — compressed 5.1 surround sound

* '''ADAT Lightpipe''' — 8 channels of uncompressed PCM at 48 kHz (professional audio; uses the same JIS F05 connector but an incompatible data format)<ref name="wp-toslink" />

 

 

* '''Electrical isolation''' — the optical connection provides complete galvanic isolation between connected devices, eliminating ground loops that can cause audible hum in copper-based audio connections

* '''Immunity to interference''' — optical signals are unaffected by electromagnetic interference (EMI) and radio frequency interference (RFI)

* '''No ground loop issues''' — a common problem with RCA-based S/PDIF coaxial connections

 

* '''Fragile connectors and cables''' — TOSLINK plugs have no locking mechanism and can be dislodged easily; cables can be damaged by tight bends

* '''Limited cable length''' — particularly with inexpensive plastic fiber cables

 

 

TOSLINK optical audio outputs are found on some higher-end and later-model CRT televisions, particularly widescreen and HD CRT sets from the late 1990s and 2000s. The optical output allows the television to pass through a digital audio signal (typically Dolby Digital from a broadcast tuner or digital cable input) to an external AV receiver or sound bar, bypassing the TV's internal speakers and DAC.

 

 

 

* [[RCA (connector)]] — carries coaxial S/PDIF digital audio (orange-coded)

* [[3.5mm TRS]] — analog audio connector; Mini-TOSLINK variant shares similar form factor

* [[HDMI Type A]] — digital interface supporting both video and high-bandwidth digital audio