US4784147A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for sidelobe suppression in scanning imaging systems
Assignee: Philips North America LLC
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Filing: 1986-12-08
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Granted: 1988-11-15
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Expires: 2006-12-08
Abstract
Abstract The paraxial, c.w. focal zone resolution of a focussed scanning imaging system is improved by choosing the ratio of the size of the apertures which are used to transmit and receive energy from the scene such that the first and second sidelobes of the system point spread function have equal amplitudes.
Inventors
- 👤 Mehran Moshfeghi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 13:30
CPC Classifications
G; G01; G01S; G01S7/00; G01S7/52; G01S7/52017; G01S7/52046; G01S7/52047; B; B06; B06B; B06B1/00; B06B1/02; B06B1/06; B06B1/0607; B06B1/0622; G10; G10K; G10K11/00; G10K11/18; G10K11/26; G10K11/32
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
92 words
In a scanning imaging system which comprises transmitting means for directing energy to a focal zone using a first aperture, receiving means for receiving energy from said focal zone using a second aperture and means for scanning said focal zone with respect to an object to produce an image, the improvement wherein the ratio of the size of said first aperture to the size of said second aperture is a number m≧1 chosen such that the amplitudes of the first and second sidelobes of the system point spread function are approximately equal.
Claim 2
Dependent Claim
92 words
In a scanning imaging system which comprises transmitting means for directing energy to a focal zone using a first aperture, receiving means for receiving energy from said focal zone using a second aperture and means for scanning said focal zone with respect to an object to produce an image, the improvement wherein the ratio of the size of said first aperture to the size of said second aperture is a number m≧1 chosen such that the amplitudes of the first and second sidelobes of the system point spread function are approximately equal.
Claim 3
Dependent Claim
26 words
The improvement of claim 1 wherein the apertures are circular and either the ratio m or the inverse ratio 1/m of their diameters is approximately 0.7683.
Claim 4
Dependent Claim
15 words
The improvement of claim 1 or 2 wherein the system is an echo ultrasound system.
Claim 5
Dependent Claim
41 words
The improvement of claim 1 or 2 wherein the system further comprises means for apodizing the distribution of energy across both of said apertures so that the apodization functions have the same threshold values at corresponding edges of the respective apertures.
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) | 1991-11-15 | 1992-05-16 | 1992-11-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-11-15 | 1996-05-16 | 1996-11-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-11-15 | 2000-05-16 | 2000-11-15 | $7700.00 | Window Closed / Lapsed |