FEATURES AND BENEFITS
QED's new Glasscore™ technology employs multiple fiber bundles of ultra-fine boro-silicate glass optical fibers (GOF) of no more than 50um each to make up the 1 mm diameter necessary to conform to the Toslink standard connectors. Because the fibers are so small the different paths taken by the light rays are similar in length virtually eliminating the timing error and introducing less distortion and jitter. This has the effect of increasing bandwidth and the accuracy of the data transmission.
STEPPED REFRACTIVE INDEX
The quartz fibers are coated with a cladding of low Refractive Index to guide the light signal.
Over 150MHz BANDWIDTH
This vastly exceeds the demands for high definition multi-channel HD digital audio. In contrast to conventional acrylic glass optical cables quartz glass cables can deliver signals up to and including 24bit/192kHz with very low jitter .
Reference Optical Quartz can provide a much higher bandwidth than a single acrylic glass fiber with 1/10th of the attenuation.
ULTRA LOW JITTER / ULTRA LOW LOSS
QED have calculated that jitter (distortions caused by timing differences between the different light paths) in conventional optical cables could typically reach up to 145ps. In Reference Optical Quartz, timing errors are virtually eliminated, introducing less distortion, jitter and ultra low loss < 0.03 dB/m.
Each fiber is thinner than a human hair. 210 fibers of 50um each are required to make
up the 1 mm diameter necessary to conform to the Toslink standard connectors.
PMMA OPTICAL FIBRES
A typical optical fiber is made of an acrylic glass material known as PMMA (Polymethyl-methacrylate). This acrylic core allows the light to take many different length paths through it. Timing differences are introduced - accounting for typically up to 145ps of Jitter.
Signal losses also occur when light is incident above the Critical Angle and is not reflected back (Yellow).
REFERENCE OPTICAL QUARTZ
Reference Optical Quartz has in excess of 210 Glasscore™ fibers each thinner than a human hair. This ensures ultra low jitter because the smaller numerical aperture reduces the range of angles of acceptance leading to straighter signal paths.
Instead of using traditional low performance polymethyl methacrylate (PMMA) plastic optical fibers (POF) which come as a single 1 mm OD fiber the cable incorporates 210+ borosilicate glass optical fires (GOF) which give improved jitter performance and higher bandwidth capability. 24 & 32 bit high resolution audio compatible.
Ultra Low Jitter
Jitter is the undesired deviation from true periodicity of an assumed periodic signal in electronics and telecommunications, often in relation to a reference clock source. A cable displaying ultra low jitter has been measured at typically 30ps.
Unique boro-silicate glass construction
Highly flexible 210 x 50 micron optical fiber bundle
Ultra low jitter
Stepped refractive index
Ultra low loss < 0.03 dB/m
24 & 32 bit high resolution audio compatible.
This QED cable comes with a two year warranty
Digital Optical Audio cables are now used widely to connect audio source equipment such as TV's, CD players and Blu-Ray players to amplifiers or receivers. There are many advantages to using the optical output from your source equipment. The optical output provides complete electrical isolation between equipment eliminating ground loops and noise induced by large external voltages or currents. With fast digital signaling using twisted pair copper cables, problems such as near end crosstalk can cause distortion of the signal; these problems are eliminated by using the digital optical connection option.
Because of the very short distances and relatively slow data signaling speeds of the Toslink system it is possible to use very inexpensive plastic optical fibers (POF) made of an acrylic glass material known as PMMA (Polymethyl-methacrylate). These are usually 1 mm in diameter to fit the Toslink connector and of course their extra width only exacerbates the time smearing or jitter caused by the multi-modes within the fiber. Calculations have shown that a typical 1m cable with a PMMA fiber of refractive index 1.5 and a critical angle of 76 degrees has the potential to introduce jitter
of up to 145ps into the SPDIF signal. These plastic optical fibers (POF) account for virtually all commercially available Digital Optical Audio cables available today.
The alternative to this situation adopted by QED in our new Glasscore™ technology cable is to employ multiple fiber bundles of ultra-fine boro-silicate glass optical fibers (GOF) of no more than 50um each (thinner than a human hair see below) to make up the 1 mm diameter necessary to conform to the Toslink standard connectors. In the new QED Reference Optical Quartz cable there are 210 such fibers each of which guide the light along a much tighter path making the different modes much more uniform than in the larger diameter single fibers.
Because the range of angles of incidence at which the light is accepted at the aperture of the cable is smaller and the critical angle of internal reflection in the glass is larger than in POF fibers the range of different paths taken by the light is reduced. In this way short data pulses are no longer artificially elongated or smeared by the physical process of travelling along the cable.
WHAT THIS CABLE IS USED FOR
Digital set-top box