Σάρωση και τηλεοπτικό σήμα

Σάρωση και τηλεοπτικό σήμα
The basic principle of image formation is
dependent on the process of scanning,
which is the same for black-and-white television,
color television, standard analog television, and
digital high-definition television.
(Zettl, Video Basics 6th Edition)
NIPKOW: ΤΟ ΠΡΩΤΟ ΣΥΣΤΗΜΑ ΤΗΛΕΟΠΤΙΚΗΣ ΣΑΡΩΣΗΣ
ΛΥΧΝΙΑ ΤΗΛΕΟΠΤΙΚΗΣ ΛΗΨΗΣ
Βefore the mid to late 1980s, a video camera tube or pickup tube was used instead of
a charge-coupled device (CCD) for converting an optical image into an electrical signal.
Several types were in use from the 1930s to the 1980s. The most commercially successful
of these tubes were various types of cathode ray tubes or "CRTs".
Vidicon-Plumbicon-Οrthicon
http://en.wikipedia.org/wiki/Video_camera_tube
ΛΥΧΝΙΑ ΤΗΛΕΟΠΤΙΚΗΣ ΛΗΨΗΣ
CCD ΤΗΛΕΟΠΤΙΚΗΣ ΛΗΨΗΣ
ΟΘΟΝΗ ΤΗΛΕΟΠΤΙΚΗΣ ΠΡΟΒΟΛΗΣ
(Zettl, Video Basics 6th Edition)
Ευρωπαϊκό Πρότυπο CCIR
Αμερικανικό
Ευρωπαϊκό
https://en.wikipedia.org/wiki/Digital_television
https://en.wikipedia.org/wiki/Digital_television
Digital television supports many different picture formats
• a combination of size and aspect ratio (width to height ratio)
Two categories:
standard-definition television (SDTV)
high definition television (HDTV)
SDTV formats (4:3 aspect-ratio):
• 640 × 480 is used in NTSC countries
• 720 × 576 is used in PAL countries
HDTV formats (16:9 aspect ratio):
• 1280 × 720 pixels in progressive scan mode (abbreviated 720p)
• 1920 × 1080 pixels in interlaced video mode (1080i)
• 1920 × 1080 at progressive scan frame rate — known as 1080p
http://en.wikipedia.org/wiki/Digital_television
http://www.emovie.gr/educational-material/videomenu
http://www.youtube.com/watch?v=8GYGxEk0btA&feature=related
http://www.youtube.com/watch?v=9A7MN4TjC2Q&feature=related
http://www.youtube.com/watch?v=LGzFz2Nrq6s&feature=related