US3813545A
Expired / Lapsed
US
⏱️ 0.0 years remaining
X-ray scan area mapping system
Assignee: EDAX INT Inc
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Filing: 1973-04-12
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Granted: 1974-05-28
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Expires: 1993-04-12
Abstract
Abstract An X-ray scan area mapping system for a scanning electron microscope provides a spacial area map display of X-ray events emitted from a specimen within at least one energy range as the specimen is scanned at scanning electron microscope rates by an electron beam. A background X-ray noise reduction circuit enables intensification of the scanning electron microscope cathode-ray tube display upon the occurrence of an X-ray event within the energy range and disables intensification when the time between consecutive X-ray events within the energy range exceeds a predetermined time period. Background X-ray events occur at much slower rates than the X-ray events emitted from the specimen within the energy range, and therefor, a substantial reduction in background noise on the scanning electron microscope display is obtained.
Inventors
- 👤 M Barnhart
- 👤 J Russ
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 14:07
CPC Classifications
H; H01; H01J; H01J37/00; H01J37/252; H01J37/256
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
184 words
An improved background X-ray noise reduction circuit in a system where X-rays are emitted from a specimen along with background X-rays upon scanning by an electron beam, and where said system has an X-ray detector, analyzing means for analyzing the energies of said detected X-rays and for producing an output pulse for each detected X-ray having an energy falling within a predetermined range of energies, said output pulses providing modulating signals for a scanning visual display device, and said background X-rays occurring at slower rates than said emitted Xrays having energies within said range, the improvement comprising: an enabler means coupled between said analyzer and said display device for applying said modulating signals to said display device for pulse modulating said display device; and a disabler means responsive to the rate of said output pulses and coupled to said enabler and to said analyzer for causing said enabler to terminate said modulating signal application to said display device when the time between consecutive output pulses exceeds a predetermined time period which is less than or equal to the expected period between consecutive noise pulses.
Claim 2
Dependent Claim
184 words
An improved background X-ray noise reduction circuit in a system where X-rays are emitted from a specimen along with background X-rays upon scanning by an electron beam, and where said system has an X-ray detector, analyzing means for analyzing the energies of said detected X-rays and for producing an output pulse for each detected X-ray having an energy falling within a predetermined range of energies, said output pulses providing modulating signals for a scanning visual display device, and said background X-rays occurring at slower rates than said emitted Xrays having energies within said range, the improvement comprising: an enabler means coupled between said analyzer and said display device for applying said modulating signals to said display device for pulse modulating said display device; and a disabler means responsive to the rate of said output pulses and coupled to said enabler and to said analyzer for causing said enabler to terminate said modulating signal application to said display device when the time between consecutive output pulses exceeds a predetermined time period which is less than or equal to the expected period between consecutive noise pulses.
Claim 3
Dependent Claim
34 words
A background X-ray noise reduction circuit in accordance with claim 1 where said enabler means is conditioned to apply said modulating signals to said display device by the first one of said output pulses.
Claim 4
Dependent Claim
86 words
A background X-ray noise reduction circuit in accordance with claim 2 where said enabler means additionally comprises means responsive to the first output pulse following said conditioning for providing said display device with a modulating signal of a fixed duration and means responsive to said disabler means for providing said display device with another modulating signal of said fixed time duration when said disabler means acts to cause said enabler means to terminate said modulating signal application to thereby provide an outline image on said device.
Claim 5
Dependent Claim
33 words
A background X-ray noise reduction circuit in accordance with claim 2 where said enabler means additionally comprises means for providing said display device with continuous modulating signals in response to said output pulses.
Claim 6
Dependent Claim
68 words
A background X-ray noise reduction circuit in accordance with claim 1 where said disabler means comprises: a counter; an oscillator coupled to said counter for driving said counter; comparator input means for providing an input condition; and a comparator coupled to said counter and to said comparator input means for comparing the condition of said counter to said input condition for providing a disabling signal when they match.
Claim 7
Dependent Claim
18 words
A background X-ray noise reduction circuit in accordance with claim 5 where said counter comprises a reset input.
Claim 8
Dependent Claim
163 words
An X-ray scan area mapping system of the type which utilizes X-rays emitted from a specimen upon scanning by an electron beam comprising: a detector means for detecting said emitted X-rays; an analyzer means coupled to said detector for analyzing the energies of said detected X-rays and for producing an output pulse for each detected X-ray having an energy falling within a predetermined energy range, said output pulses providing modulating signals for a scanning visual display device; an enabler means coupled between said analyzer and said display device for applying said modulating signals to said display device for pulse modulating said display device; aNd a disabler means responsive to the rate of said output pulses coupled to said enabler and to said analyzer for causing said enabler to terminate said modulating signal application to said display device when the time between consecutive output pulses exceeds a predetermined time period which is less than or equal to the expected period between consecutive noise pulses.
Claim 9
Dependent Claim
163 words
An X-ray scan area mapping system of the type which utilizes X-rays emitted from a specimen upon scanning by an electron beam comprising: a detector means for detecting said emitted X-rays; an analyzer means coupled to said detector for analyzing the energies of said detected X-rays and for producing an output pulse for each detected X-ray having an energy falling within a predetermined energy range, said output pulses providing modulating signals for a scanning visual display device; an enabler means coupled between said analyzer and said display device for applying said modulating signals to said display device for pulse modulating said display device; aNd a disabler means responsive to the rate of said output pulses coupled to said enabler and to said analyzer for causing said enabler to terminate said modulating signal application to said display device when the time between consecutive output pulses exceeds a predetermined time period which is less than or equal to the expected period between consecutive noise pulses.
Claim 10
Dependent Claim
34 words
An X-ray scan area mapping system in accordance with claim 7 where said enabler means is conditioned to apply said modulating signals to said display device by the first one of said output pulses.
Claim 11
Dependent Claim
33 words
An X-ray scan area mapping system in accordance with claim 8 where said enabler means additionally comprises means for providing said display device with continuous modulating signals in response to said outupt pulses.
Claim 12
Dependent Claim
87 words
An X-ray scan area mapping system in accordance with claim 8 where said enabler means additionally comprises means responsive to the first output pulse following said conditioning for providing said display device with a modulating signal of a fixed time duration and means responsive to said disabler means for providing said display device with another modulating signal of said fixed time duration when said disabler means acts to cause said enabler means to terminate said modulating signal application to thereby provide an outline image on said device.
Claim 13
Dependent Claim
79 words
An X-ray scan area mapping system in accordance with claim 7 where said disabler means comprises: a counter coupled to said analyzer means; an oscillator coupled to said counter for driving said counter; comparator input means for providing an input condition; and a comparator coupled to said counter and to said comparator input means for comparing the condition of said counter to said input condition supplied by said comparator input means for providing a disabling signal when they match.
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) | 1977-05-27 | 1977-11-26 | 1978-05-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-05-27 | 1981-11-26 | 1982-05-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-05-27 | 1985-11-26 | 1986-05-28 | $7700.00 | Window Closed / Lapsed |