US5136628A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Video telephone
Assignee: Sony Corp
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Filing: 1988-06-24
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Granted: 1992-08-04
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Expires: 2008-06-24
Abstract
Abstract A video telephone for transmitting video data of a still picture through an audio signal line includes an image pickup tube for picking up a picture of the still picture, an A/D (analog-to-digital) converter for converting the analog output picked up by the image pick-up tube to the form of a digital signal, a memory for storing the output of the A/D converter as video data, a modulating circuit for modulating the video data stored in the memory into a modulated signal of an occupied frequency band corresponding to a transmission band of the signal line, a circuit for transmitting the modulated output of the modulating circuit to the signal line, a circuit for generating a synchronizing pulse and a frequency-dividing circuit for frequency-dividing the color subcarrier signal to provide signals necessary for the A/D converter, the memory, and the modulating circuit, wherein the video data is a signal which results from thinning the picked-up output at a predetermined ratio.
Inventors
- 👤 Shoji Araki
- 👤 Yukinobu Takano
- 👤 Tadahisa Yamamoto
- 👤 Noriyuki Uchiumi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 20:45
CPC Classifications
H; H04; H04N; H04N7/00; H04N7/14; H04N7/141; H04N19/00; H04N19/50; H04N19/587; H04N7/01; H04N7/24
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
245 words
A video telephone for transmitting video data of a still picture through an audio signal line comprising: a) an image pick-up tube for picking up a picture of said still picture in accordance with the standard television systems, such as the NTSC system; b) an A/D (analog-to-digital) converter for converting the analog output picked up by said image pick-up tube to form a digital signal; c) a memory for storing the output of said A/D converter as video data; d) a modulating circuit for modulating said video data stored in said memory into a modulated signal having a predetermined frequency band corresponding to a transmission band of said signal line; e) a circuit for transmitting the modulated output of said modulating circuit to said signal line; f) a circuit for generating a color subcarrier signal of said standard television system and a synchronizing pulse of said standard television system and for supplying said subcarrier signal and said synchronizing pulse to said image pick-up tube; and g) a frequency-dividing circuit for producing from said color subcarrier signal, the signals necessary for said A/D converter, said memory and said modulating circuit, wherein said video data is a signal which results from thinning said picked-up output at a predetermined ratio and a signal, corresponding to an effective picture screen of which the upper, lower, right and left portions are removed, in a frame shape is extended to the whole of said effective picture screen by an over-scan operation.
Claim 2
Dependent Claim
245 words
A video telephone for transmitting video data of a still picture through an audio signal line comprising: a) an image pick-up tube for picking up a picture of said still picture in accordance with the standard television systems, such as the NTSC system; b) an A/D (analog-to-digital) converter for converting the analog output picked up by said image pick-up tube to form a digital signal; c) a memory for storing the output of said A/D converter as video data; d) a modulating circuit for modulating said video data stored in said memory into a modulated signal having a predetermined frequency band corresponding to a transmission band of said signal line; e) a circuit for transmitting the modulated output of said modulating circuit to said signal line; f) a circuit for generating a color subcarrier signal of said standard television system and a synchronizing pulse of said standard television system and for supplying said subcarrier signal and said synchronizing pulse to said image pick-up tube; and g) a frequency-dividing circuit for producing from said color subcarrier signal, the signals necessary for said A/D converter, said memory and said modulating circuit, wherein said video data is a signal which results from thinning said picked-up output at a predetermined ratio and a signal, corresponding to an effective picture screen of which the upper, lower, right and left portions are removed, in a frame shape is extended to the whole of said effective picture screen by an over-scan operation.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-08-04 | 1996-02-03 | 1996-08-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-08-04 | 2000-02-03 | 2000-08-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-08-04 | 2004-02-03 | 2004-08-04 | $7700.00 | Window Closed / Lapsed |