US3723647A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for recording television images on film
Assignee: Bell and Howell Co
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Filing: 1972-04-20
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Granted: 1973-03-27
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Expires: 1992-04-20
Abstract
Abstract An apparatus for synchronizing the operation of a motion picture camera to a television receiver to prevent ''''shutter bars'''' in the projected film image. The vertical retrace pulses from the television receiver are sensed, amplified and fed to an energy storage counter. The storage counter provides one output pulse for every fourth retrace pulse. The output of the storage counter is fed to one input of a bistable multivibrator. The camera includes a 180* rotary shutter coupled to a pulse generator. The output of the pulse generator is fed to the second input of the multivibrator and the output of the multivibrator controls the camera motor. In this manner, the speed of the camera shutter is synchronized to the television retrace signal and the shutter phase angle with respect to the retrace signal remains constant.
Inventors
- 👤 R John
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 05:09
CPC Classifications
H; H04; H04N; H04N5/00; H04N5/76; H04N5/84; H04N5/843; H04N5/846; G; G03; G03B; G03B31/00; G03B31/02
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
126 words
An apparatus for synchronizing the operation of a motion picture camera with a television receiver to permit the filming of the television cathode ray tube image comprising: signal generating means coupled to the camera shutter for generating a signal related to the movement of the shutter; pulse detecting means for detecting the vertical retrace pulse signals generated by the television receiver; comparison means for comparing the signal from the camera generating means with the signal from the vertical pulse detecting means and providing an output signal related thereto; and a camera motor control means receiving the output signal from said comparison means and serving to control the speed of movement of the camera shutter so as to maintain synchronization between the camera and the television receiver.
Claim 2
Independent Claim
126 words
An apparatus for synchronizing the operation of a motion picture camera with a television receiver to permit the filming of the television cathode ray tube image comprising: signal generating means coupled to the camera shutter for generating a signal related to the movement of the shutter; pulse detecting means for detecting the vertical retrace pulse signals generated by the television receiver; comparison means for comparing the signal from the camera generating means with the signal from the vertical pulse detecting means and providing an output signal related thereto; and a camera motor control means receiving the output signal from said comparison means and serving to control the speed of movement of the camera shutter so as to maintain synchronization between the camera and the television receiver.
Claim 3
Dependent Claim
55 words
The apparatus of claim 1 which further includes frequency translating means for translating the frequency of the output of the vertical pulse detecting means to a second frequency said second frequency being compared with the output of said camera signal generating means for maintaining synchronization between the operation of the camera and the tElevision receiver.
Claim 4
Dependent Claim
43 words
The apparatus of claim 2 wherein said vertical pulse detecting means comprises an inductance suitable for positioning adjacent the neck of the cathode ray tube of the television and serving to pick up the vertical retrace pulses applied to the cathode ray tube.
Claim 5
Dependent Claim
55 words
The apparatus of claim 3 wherein said inductance of said vertical pulse detecting means is capacitively tuned to the frequency of the vertical retrace pulses of the television set and wherein the voltage developed across said tuned circuit is amplified by means of an amplifier stage prior to frequency translation by said frequency translation means.
Claim 6
Dependent Claim
28 words
The apparatus of claim 2 wherein said frequency translating means comprises a frequency divider for providing an output signal frequency which is lower than the vertical retrace frequency.
Claim 7
Dependent Claim
29 words
The apparatus of claim 5 wherein said frequency divider is in the form of an energy storage counter providing a single output pulse for each four vertical retrace pulses.
Claim 8
Dependent Claim
45 words
The apparatus of claim 5 wherein said comparison means comprises a bistable multivibrator having a first input which is triggered by the output of said frequency divider and a second input of which is triggered by the output signal from said camera signal generating means.
Claim 9
Dependent Claim
44 words
The apparatus of claim 7 wherein said vertical pulse detecting means comprises an inductance suitable for positioning adjacent the neck of the cathode ray tube of the television set and serving to pick up the vertical retrace pulses applied to the cathode ray tube.
Claim 10
Dependent Claim
29 words
The apparatus of claim 8 wherein said frequency divider is in the form of an energy storage counter providing a single output pulse for each four vertical retrace pulses.
Claim 11
Dependent Claim
17 words
The apparatus of claim 9 wherein the camera includes a rotary shutter having a 180* shutter angle.
References Cited (Backward Citations)
US3317663A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-03-26 | 1976-09-25 | 1977-03-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-26 | 1980-09-25 | 1981-03-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-26 | 1984-09-25 | 1985-03-27 | $7700.00 | Window Closed / Lapsed |