miniature TVs built into spectacles to give a true 3D effect.
5. Analogue Interconnections
Terrestrial TV signals are demodulated to produce a
composite video signal and two separate audio outputs. The composite video
signal is then used to derive the black-and-white (luminance) and colour
(chrominance) signals. VCRs record colour signals in this format, known as Y/C
or S-VHS:
The chrominance signal is then used to derive two
«colour-difference» signals (R-Y) and (B-Y) which (together with the luminance
signal) are known as the Component Video signals – DVD players reproduce
signals in this format.
The three component video signals are then derived to
produce the Red, Green and Blue (RGB) waveforms required by a colour TV display
device.
Some TV receivers can accept signals in any of the above
formats, having SCART socket(s) for the composite video and RGB inputs, a DIN
connector for S-VHS and separate connectors for component video. The
conversion of a video signal into its luminance and chrominance components
introduces degradations to the picture, and this process should be avoided wherever
possible. Since a VCR reproduces a signal in the S-VHS format, the best
results would be obtained using the receiver’s S-VHS input. Similarly, a DVD
player reproduces signals in the component video format so the component video
input should be used.
Analogue audio signals can be interconnected using SCART or
phono (RCA) connections to produce monaural, stereo or Dolby Pro-Logic surround
sound. Dolby Digital data requires either a single coaxial cable or an optical
link and is backwards compatible, being able to produce either a two-channel
stereo mix for regular stereo playback, or a mono mix for playback through a
monaural system.