US3602718A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Means for measuring the duration of very short light pulses,such as laser pulses
Assignee: Alcatel Lucent SAS
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Filing: 1969-06-02
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Granted: 1971-08-31
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Expires: 1989-06-02
Abstract
Abstract Automatic device for measuring the duration of a very short light pulse, such as a laser pulse, by a correlation procedure from two ''''half pulses'''' including two lines; each provoking a different optical delay.
Inventors
- 👤 Maurice B Michon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 22:50
CPC Classifications
G; G01; G01J; G01J11/00; G04; G04F; G04F13/00; G04F13/02; G04F13/026
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
112 words
A device for measuring the duration of a short light pulse comprising: a. means for separating an initial light pulse into two halfpulses having substantially the same duration as said initial pulse, b. means for passing said half-pulses along two different optical paths, c. optical means for obtaining on respective different light paths corresponding secondary light pulse trains having substantially the same duration as said half-pulses, d. means for staggering each secondary pulse of one of said pulse trains with respect to corresponding pulses of the other pulse train, by a given proportional quantity, and e. means for superposing said pulse trains and a photosensitive detector arranged at the point of superposition.
Claim 2
Independent Claim
112 words
A device for measuring the duration of a short light pulse comprising: a. means for separating an initial light pulse into two halfpulses having substantially the same duration as said initial pulse, b. means for passing said half-pulses along two different optical paths, c. optical means for obtaining on respective different light paths corresponding secondary light pulse trains having substantially the same duration as said half-pulses, d. means for staggering each secondary pulse of one of said pulse trains with respect to corresponding pulses of the other pulse train, by a given proportional quantity, and e. means for superposing said pulse trains and a photosensitive detector arranged at the point of superposition.
Claim 3
Dependent Claim
19 words
The device according to claim 1, wherein said means for obtaining pulse trains comprise two different optical delay lines.
Claim 4
Dependent Claim
26 words
The device according to claim 2, wherein each delay line comprises two parallel plane mirrors, one of which is semireflecting and the other having total reflection.
Claim 5
Dependent Claim
26 words
The device according to claim 3, further comprising cavities inclined by a very small angle with respect to the perpendicular to the path of said half-pulses.
Claim 6
Dependent Claim
42 words
The device according to claim 3, wherein said means for separating the initial pulse into two half pulses comprises a semireflecting thin plate arranged substantially in the plane of bisection of the dihedron formed by the planes of said total reflection mirrors.
Claim 7
Dependent Claim
26 words
The device according to claim 3, further comprising a parallel face plate of the ''''quarter-wave'''' type, arranged between one of the cavities and the semireflecting plate.
Claim 8
Dependent Claim
104 words
The device according to claim 1, wherein the means separating the initial pulse into two half-pulses and said means for obtaining secondary pulse trains comprises a cavity involving a first, total reflection face, having an opening opposite of which there is arranged a first focusing means and a second semireflecting face, behind which are arranged second focusing means, a screen having two holes situated at different distances from the optical axis of said cavity and arranged essentially at the output of said second focusing means, and means diverting a light beam arranged opposite the perforation of said screen furthest removed from said optical axis.
Claim 9
Dependent Claim
23 words
The device according to claim 7, above, wherein said means for superposing the paths of the two pulse trains is a converging lens.
Claim 10
Dependent Claim
102 words
The device according to claim 1 above, wherein said means for breaking up the initial pulse into two half-pulses and said means for obtaining the two pulse trains, comprise two adjacent tanks with semireflecting walls whose entrance face has a layer that is opaque except in a central zone extending on either side of the wall separating the two adjacent tanks, said two tanks being filled respectively, with two fluids having a different refraction index, screen involving two axial holes situated at an equal distance from the plane defined by the separating wall between the two tanks and arranged behind said tanks.
Claim 11
Dependent Claim
22 words
The device according to claim 9, wherein said two fluids with the different refraction index are the same gas at different pressures.
Claim 12
Dependent Claim
13 words
The device according to claim 9, wherein the two fluids are different gases.
Claim 13
Dependent Claim
35 words
The device according to claim 1, wherein said means for obtaining two pulse trains, are two tanks whose walls are parallel and semireflecting with said tanks being filled with fluids having a different refraction index.
Claim 14
Dependent Claim
77 words
The device according to claim 1, wherein said means for obtaining the two light pulse trains, comprise a thin plate with a parallel face, made of birefringent material, two plates with parallel faces making it possible to turn, by 90* the plane of polarization of a light arranged on either side of said birefringent material plate, and one of the two first plates is arranged on the path of the pulse train corresponding to the other half-pulse.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-08-30 | 1975-03-01 | 1975-08-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-08-30 | 1979-03-01 | 1979-08-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-08-30 | 1983-03-01 | 1983-08-31 | $7700.00 | Window Closed / Lapsed |