US4001492A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Half tone reproducing process in facsimile
Assignee: Fujifilm Business Innovation Corp
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Filing: 1973-02-06
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Granted: 1977-01-04
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Expires: 1993-02-06
Abstract
Abstract A half tone reproducing circuitry in a facsimile system characterized by circuitry for pulse number modulating the image signal of an image including half tone circuitry for eliminating those pulses from the pulse frequency modulated signal occurring during the white portion of the image signal and circuitry for on and off controlling an image recording device by the modulated signal thereby reproducing the half tone of the image.
Inventors
- 👤 Matsumi Suzuki
- 👤 Toshi Itoh
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 13:36
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/40; H04N1/405; H04N1/4051
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
148 words
Half tone reproducing circuitry in a facsimile system comprising a means for pulse frequency modulating the image signal of an image including half tone, and a pulse eliminating means for eliminating those pulses from the pulse frequency modulated signal occurring during the white portion of the image signal; and a means for applying the output signal from said pulse eliminating means to an image recording device to reproduce the image including half tone, said pulse eliminating means comprising threshold means responsive to said image signal for developing a control signal which is at a first level when said image signal is non-white and at a second level when said image signal is white; and means responsive to the pulse frequency modulated signal and said control signal for eliminating said pulses occurring during said white portion of said image signal when said control signal is at said second level.
Claim 2
Dependent Claim
148 words
Half tone reproducing circuitry in a facsimile system comprising a means for pulse frequency modulating the image signal of an image including half tone, and a pulse eliminating means for eliminating those pulses from the pulse frequency modulated signal occurring during the white portion of the image signal; and a means for applying the output signal from said pulse eliminating means to an image recording device to reproduce the image including half tone, said pulse eliminating means comprising threshold means responsive to said image signal for developing a control signal which is at a first level when said image signal is non-white and at a second level when said image signal is white; and means responsive to the pulse frequency modulated signal and said control signal for eliminating said pulses occurring during said white portion of said image signal when said control signal is at said second level.
Claim 3
Dependent Claim
18 words
Facsimile circuitry as in claim 1 including differentiating means responsive to the output signal from said modulating means.
References Cited (Backward Citations)
US2283415A
Cited
US2263986A
Cited
US3197558A
Cited
US3564131A
Cited
US3580995A
Cited
US3613103A
Cited
US3751587A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-01-04 | 1980-07-05 | 1981-01-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-01-04 | 1984-07-05 | 1985-01-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-01-04 | 1988-07-05 | 1989-01-04 | $7700.00 | Window Closed / Lapsed |