GoKawiilTech Tangents (TT) surprised themselves by looking at the surface of a CED ‘LaserDisc’ under a microscope and felt compelled to purchase a new device, with a built-in screen and HDMI out, to share what they had discovered. Spoiler alert: You can clearly see some of the analog imagery stored on a CED surface.
Microscopes can See Video on a LaserDisc - Andonstar AD246S-P - YouTube Watch On
Though the media looks quite a lot like a LaserDisc, a CED (Capacitance Electronic Disc) is an unusual video distribution format that existed for a time alongside the far better known VHS and BetaMax videotape era. It consisted of a vinyl-like disc, distributed and maintained for its own protection in a caddy, and it was read by a needle-loaded cartridge just like ye olde music LPs and singles.
Like its tape format rivals, the video content stored on a CED was in a standard-definition quality analog form. So, looking extremely closely at the grooved surface can actually give you more than a clue to the content of the disc.
Article continues below
Enjoying the new microscope
After introducing his new microscope and its capabilities, TT finally gets down to some close-up disc scrutiny at around the 14mins mark. Specifically, he zooms in on the surfaces of two samples of actual CEDs. These contain generally better quality (though still analog) video tracks, which were read by a laser pickup. Some of the later LaserDiscs were enhanced with digital PCM audio tracks.
One of the CEDs examined closely was a CAV (Constant Angular Velocity) disc, with its data evidenced by a consistent geometric pattern, whereas a CLV (Constant Linear Velocity) disc under the microscope looks simply colorfully streaky.
“I found an image!”
Now studying the CED surface more earnestly, something caught TT’s eye. “It's not going to happen. We're not going to find an image.” Then, almost immediately, “I found an image.”
... continue reading