Patent US4221960A successfully refreshed from Google Patents.
US4221960A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for stabilizing a modulated light ray
Assignee: Dainippon Screen Manufacturing Co Ltd
•
Filing: 1978-11-13
•
Granted: 1980-09-09
•
Expires: 1998-11-13
Abstract
Abstract A light ray emitted by a light source and which is to be modulated by an acoustic-optical modulator element is stabilized by its intensity being detected before it enters the acoustic-optical modulator element and being used to produce correction signals. The correction signals are used to amplitude-modulate a high-frequency carrier in reverse phase to the change of intensity of the light ray, to produce corrected carrier signals. Then the corrected carrier signals are further amplitude-modulated by control signals to produce modulator signals which are used to modulate the light ray in the acoustic-optical modulator element.
Inventors
- 👤 Kiyoshi Maeda
- 👤 Kyohei Fujisawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 14:20
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/0121; H; H05; H05B; H05B47/00; H05B47/10; G02F1/11; G02F1/113
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
102 words
A method for stabilizing the intensity of a light ray emitted by a light source and modulated in an optical modulator element according to control signals, comprising: detecting the change of intensity of the light ray before it enters the optical modulator element and producing correction signals in accordance therewith; amplitude-modulating a high-frequency carrier by the correction signals in reverse phase to the change of intensity of the light ray to produce corrected carrier signals; amplitude-modulating the corrected carrier signals by the control signals to produce modulator signals; and modulating the light ray by the modulator signals in the optical modulator element.
Claim 2
Independent Claim
102 words
A method for stabilizing the intensity of a light ray emitted by a light source and modulated in an optical modulator element according to control signals, comprising: detecting the change of intensity of the light ray before it enters the optical modulator element and producing correction signals in accordance therewith; amplitude-modulating a high-frequency carrier by the correction signals in reverse phase to the change of intensity of the light ray to produce corrected carrier signals; amplitude-modulating the corrected carrier signals by the control signals to produce modulator signals; and modulating the light ray by the modulator signals in the optical modulator element.
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) | 1983-09-09 | 1984-03-10 | 1984-09-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-09-09 | 1988-03-10 | 1988-09-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-09-09 | 1992-03-10 | 1992-09-09 | $7700.00 | Window Closed / Lapsed |