Dynamic information storage or retrieval – Dynamic mechanism subsystem – Having power driven transducer assembly
Reexamination Certificate
1999-06-08
2001-07-17
Ometz, David L. (Department: 2652)
Dynamic information storage or retrieval
Dynamic mechanism subsystem
Having power driven transducer assembly
C369S244100
Reexamination Certificate
active
06262964
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a system for a video program service, so-called Video On Demand (VOD) system, which supplies video programs utilizing a CATV system or the like in response to user's requests, and more particularly to a technique for obtaining plural reproduction signals of the same video program simultaneously from a unique video disc.
2. Description of the Prior Art
There is known a disc reproduction device having an ability to reproduce video signals from a unique video disc at different times (hereinafter referred to as “VOD reproduction”). The device of this type is equipped with a plurality of pickups for reading information and guide bars for supporting the pickups around a rotary axis of the disc. The device can reproduce a plurality of video signals simultaneously from a unique disc with a single disc rotation mechanism. It is preferable in the VOD reproduction that the video programs periodically start with approximately same time intervals between them. The interval of the program starting times is put the following limit:
Limit of time interval=(total reproduction time of the program)/(the number of the pickup device). Since the user generally wishes to watch the video program from the start, he or she needs to wait for the start of the next program. Shortening the time interval of the programs contributes to the reduction of the user's waiting time. In this view, in order to reduce the user's waiting time, it is required to equip the VOD reproduction device with as many pickup devices as possible. For example, where a video program requiring two hour reproduction time is reproduced using four pickup devices, the time interval of the starting time is a half hour (two hours/4 pickups). Namely, the same program is reproduced four times with delay times of a half hour between them.
However, in the above described VOD reproduction device, the physical shape and the structure of the pickup device put the limitation on the number of pickup device to be equipped, and therefore it is difficult to reduce the time interval of the programs beyond a certain extent. Specifically, the known reproduction device is provided with the guiding mechanism of the pickup (e.g., guide bar) on both sides of the pickup to ensure the smooth transfer of the pickup in the radial direction of the disc. Therefore, if the guide bars are arranged closely to each other so as to increase the number of the pickup device, they contact and interfere with each other in the proximity of the rotary axis of the disc due to their structural features (this phenomenon is hereinafter referred to as “interference”).
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a disc player capable of reducing the program waiting time of the user in VOD reproduction.
According to one aspect of the present invention, there is provided a disc player including: a plurality of pickup devices for reading information from a disc; and a plurality of guide devices having a longitudinal axis for transferring the pickup device, the longitudinal axis being directed in a direction rotated by a predetermined angle with respect to a radial direction of the disc.
According to another aspect of the present invention, there is provided a disc player including at least one pickup device, the pickup device including: a first pickup device movable substantially in a radial direction of a disc for reading information from the disc; and a second pickup device movable substantially in the radial direction of the disc for reading information from the disc, the first pickup device and the second pickup device being movable in dependently of and in parallel with each other.
According to still another aspect of the present invention, there is provided a disc player including: a plurality of pickup devices for reading information from the disc; and a plurality of guide devices arranged radiately from a center of the disc for transferring the pickup device in a radial direction of the disc, the plurality of guide devices including: first guide devices for raising the pickup device at an inner circumferential portion of the disc; and second guide devices for bringing the pickup device down at the inner circumferential portion of the disc, the first guide devices and the second guide devices being arranged alternately in a circumferential direction of the disc.
According to still another aspect of the present invention, there is provided a disc player including: first pickup devices arranged in alignment with each other in a radial direction of a disc for reading information from the disc; second pickup devices arranged in alignment with each other in the radial direction of the disc for reading information from the disc; and device for moving the first pickup devices and the second pickup devices in the radial direction of the disc, the first pickup devices being arranged in parallel with the second pickup devices.
The nature, utility, and further features of this invention will be more clearly apparent from the following detailed description with respect to preferred embodiment of the invention when read in conjunction with the accompanying drawings briefly described below.
REFERENCES:
patent: 5027340 (1991-06-01), Yumura et al.
patent: 5600623 (1997-02-01), Miyazaki et al.
patent: 5719848 (1998-02-01), Ikegame
patent: 54-114220 (1979-09-01), None
patent: 63-214935 (1988-09-01), None
patent: 1-118246 (1989-05-01), None
patent: 1-151074 (1989-06-01), None
patent: 1-182979 (1989-07-01), None
patent: 3-203031 (1991-09-01), None
patent: 5-47000 (1993-02-01), None
patent: 6-60389 (1994-03-01), None
Hirano Hiroyuki
Ishii Katsumi
Matsumoto Kanya
Naito Ryuichi
Naohara Shinichi
Ometz David L.
Pioneer Electronic Corporation
Pitney Hardin Kipp & Szuch LLP
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