Ricoh Company, Ltd.

Isamu Orima

Wasaburo Ohta

Kazuhiro Umeki

Masashi Nakazawa

Kiyoshi Sone

Yuzi Onodera

Hitoshi Sone

An optical information recording medium, for writing in and reading out information by a laser beam, is composed of a recording layer, an anti-reflection layer structure formed on an outer surface section on which the laser beam is directed to be focused, on the recording layer, and the anti-reflection layer structure includes one or more transparent electroconductive film layers.

Optical information recording medium

Video signals are transferred from a phonograph record or low speed magnetic tape and stored on a magnetic sheet disc rotating at low speed. The magnetic sheet disc is then rotated at high speed to output the video signals to a television display or the like. In the invention, clock signals representing equal intervals of time are provided with the video signals on the phonograph record or low speed magnetic tape. The signals are picked up when the record or tape is rotated and the frequency thereof is analogous to the instantaneous rotational speed of the record or tape drive motor. The video is stored on the magnetic sheet disc by a write head. The magnetic sheet disc is provided withreference marks which are sensed when the magnetic sheet disc is rotated and the frequency thereof is analogous to the instantaneous rotational speed of the disc relative to the write head. The two frequencies are compared. The speed of the disc relative to the write head is controlled by varying the speed of the disc and/or rotating the write head relative to the disc so that the ratio of the instantaneous speed of the record or low speed tape to the design speed thereof is equal to the ratio of the instantaneous speed of the disc relative to the write head to the design speed of the disc. The video signals are thereby stored on the disc in the correct positions to eliminate jitter on the television display.

Jitter prevention system for video signal processing

Growing community of inventors

Yokohama, Japan

Isamu Orima