US3795836A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Intensity limiting means for cathode ray oscilloscope
Assignee: Saab Bofors AB
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Filing: 1972-02-29
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Granted: 1974-03-05
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Expires: 1992-02-29
Abstract
Abstract Display apparatus including a cathode ray oscilloscope is provided, primarily but not exclusively for thermography, to obtain photographic records of the oscilloscope image without danger of overexposing the photosensitive film. The apparatus includes means to limit the intensity of the oscilloscope image which means is presettable to modify the image signal (i.e., the signal normally determining intensity) only when its amplitude exceeds a predetermined value, whereby the image intensity is prevented from exceeding a desired maximum corresponding to the characteristics of the film and a given exposure time and aperture. Circuits are described for suppressing the electron beam when its intensity would otherwise exceed the desired maximum.
Inventors
- 👤 A Nilsson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 09:31
CPC Classifications
G; G03; G03B; G03B15/00; G03B15/003; H; H04; H04N; H04N23/00; H04N23/20; H04N23/23
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
227 words
In display apparatus for a cathode ray oscilloscope of the type having a screen, electron beam controlling means for producing an image on the screen, and intensity modulating means responsive to an electrical image signal to control the intensity of the image on said screen, the improvement comprising: intensity limiting means presettable to modify the image signal only when its amplitude exceeds a predetermined value and including; a variable voltage divider to which said image signal is applied, a transistor whose base is connected to the tap on said voltage divider, said transistor conducting when said image signal exceeds said predetermined value and being then effective to render said intensity modulating means ineffective, said intensity limiting means further including second and third transistors, the collector of said first transistor being connected by a first resistor to the base of the second transistor, the emitter of said second transistor being connected to a first fixed potential source, the collector of said second transistor being connected via a second resistor to the emitter of said third transistor, the base of said third transistor being supplied with said image signal, and the collector of said third transistor being connected on the one hand to said intensity modulating means, and on the other hand via a third resistor to a second fixed potential source for extinguishing the beam of the oscilloscope.
Claim 2
Dependent Claim
227 words
In display apparatus for a cathode ray oscilloscope of the type having a screen, electron beam controlling means for producing an image on the screen, and intensity modulating means responsive to an electrical image signal to control the intensity of the image on said screen, the improvement comprising: intensity limiting means presettable to modify the image signal only when its amplitude exceeds a predetermined value and including; a variable voltage divider to which said image signal is applied, a transistor whose base is connected to the tap on said voltage divider, said transistor conducting when said image signal exceeds said predetermined value and being then effective to render said intensity modulating means ineffective, said intensity limiting means further including second and third transistors, the collector of said first transistor being connected by a first resistor to the base of the second transistor, the emitter of said second transistor being connected to a first fixed potential source, the collector of said second transistor being connected via a second resistor to the emitter of said third transistor, the base of said third transistor being supplied with said image signal, and the collector of said third transistor being connected on the one hand to said intensity modulating means, and on the other hand via a third resistor to a second fixed potential source for extinguishing the beam of the oscilloscope.
Claim 3
Dependent Claim
162 words
In display apparatus for a cathode ray oscilloscope of the type having a screen, electron beam controlling means for producing an image on the screen, and intensity modulating means responsive to an electrical image signal to control the intensity of the image on said screen, the improvement comprising: intensity limiting means presettable to modify the image signal only when its amplitude exceeds a predetermined value and including a variable voltage divider to which said image signal is applied, said intensity limiting means including; a transistor whose base is connected to the tap on said voltage divider, said transistor conducting when said image signal exceeds said predetermined value and being then effective to render said intensity modulating means ineffective, and a further transistor having its base supplied with said image signal and its collector connected to said intensity modulating means, the collector of said first transistor being connected via a resistor to the image signal channel at the base of said further transistor.
Claim 4
Dependent Claim
162 words
In display apparatus for a cathode ray oscilloscope of the type having a screen, electron beam controlling means for producing an image on the screen, and intensity modulating means responsive to an electrical image signal to control the intensity of the image on said screen, the improvement comprising: intensity limiting means presettable to modify the image signal only when its amplitude exceeds a predetermined value and including a variable voltage divider to which said image signal is applied, said intensity limiting means including; a transistor whose base is connected to the tap on said voltage divider, said transistor conducting when said image signal exceeds said predetermined value and being then effective to render said intensity modulating means ineffective, and a further transistor having its base supplied with said image signal and its collector connected to said intensity modulating means, the collector of said first transistor being connected via a resistor to the image signal channel at the base of said further transistor.
Claim 5
Dependent Claim
173 words
In display apparatus for a cathode ray oscilloscope of the type having a screen, electron beam controlling means for producing an image on the screen, and intensity modulating means responsive to an electrical image signal to control the intensity of the image on said screen, the improvement comprising: intensity limiting means presettable to modify the image signal only when tis amplitude exceeds a predetermined value and including; a variable voltage divider to which said image signal is applied, a transistor whose base is connected to the tap on said voltage divider, said transistor conducting when said image signal exceedS said predetermined value, a further transistor having its base supplied with the image signal and its collector connected to the intensity modulating means, said first transistor being connected via a resistor to the base of said further transistor, the collector of said further transistor being connected via a resistor to a higher potential than that of the emitter of said further transistor and being connected also to the intensity modulating means of the oscilloscope.
Claim 6
Dependent Claim
173 words
In display apparatus for a cathode ray oscilloscope of the type having a screen, electron beam controlling means for producing an image on the screen, and intensity modulating means responsive to an electrical image signal to control the intensity of the image on said screen, the improvement comprising: intensity limiting means presettable to modify the image signal only when tis amplitude exceeds a predetermined value and including; a variable voltage divider to which said image signal is applied, a transistor whose base is connected to the tap on said voltage divider, said transistor conducting when said image signal exceedS said predetermined value, a further transistor having its base supplied with the image signal and its collector connected to the intensity modulating means, said first transistor being connected via a resistor to the base of said further transistor, the collector of said further transistor being connected via a resistor to a higher potential than that of the emitter of said further transistor and being connected also to the intensity modulating means of the oscilloscope.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-03-04 | 1977-09-03 | 1978-03-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-03-04 | 1981-09-03 | 1982-03-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-03-04 | 1985-09-03 | 1986-03-05 | $7700.00 | Window Closed / Lapsed |