US3761614A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electron-optical image tubes and image tube streak cameras
Assignee: Individual
•
Filing: 1971-06-24
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Granted: 1973-09-25
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Expires: 1991-06-24
Abstract
Abstract An electron-optical image tube is made capable of providing direct measurement of luminous events having durations as short as one picosecond and with a time resolution in the picosecond range by providing a metallic mesh extraction electrode in close proximity to the photo-cathode of the image tube and connecting this extraction electrode to a source of positive potential of variable voltage. An image tube streak camera incorporating such an image tube provides means whereby the photo-electrons in the image tube are deflected by a pulsed electric field of rapid rise time to produce a streaked record. The image tube is particularly suited for use in the analysis of laser beam pulses.
Inventors
- 👤 D Bradley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 23:55
CPC Classifications
G; G04; G04F; G04F13/00; G04F13/02; G04F13/026; H; H01; H01J; H01J31/00; H01J31/08; H01J31/50; H01J31/501; H01J31/502
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
156 words
A streaking image tube comprising a photocathode for receiving light images of picosecond duration and converting them to photoelectrons, an extraction electrode consisting of a mesh immediately adjacent to the emission side of the photocathode, a source of positive voltage connected to said mesh to maintain the mesh at a constant positive potential with respect to the photocathode to accelerate the photoelectrons away from the photocathode, a screen for receiving the photoelectrons, and deflection electrode means on the path of the photoelectrons between the mesh and the screen for periodically deflecting said photoelectrons normally to their direction of movement after acceleration thereof, the magnitude of the voltage difference between the photocathode and the mesh and the separation of the photocathode and the mesh being such that the photoelectrons are positively accelerated away from the photocathode at such values that a time resolution in the picosecond range is obtainable in the streak image produced at the screen.
Claim 2
Dependent Claim
156 words
A streaking image tube comprising a photocathode for receiving light images of picosecond duration and converting them to photoelectrons, an extraction electrode consisting of a mesh immediately adjacent to the emission side of the photocathode, a source of positive voltage connected to said mesh to maintain the mesh at a constant positive potential with respect to the photocathode to accelerate the photoelectrons away from the photocathode, a screen for receiving the photoelectrons, and deflection electrode means on the path of the photoelectrons between the mesh and the screen for periodically deflecting said photoelectrons normally to their direction of movement after acceleration thereof, the magnitude of the voltage difference between the photocathode and the mesh and the separation of the photocathode and the mesh being such that the photoelectrons are positively accelerated away from the photocathode at such values that a time resolution in the picosecond range is obtainable in the streak image produced at the screen.
Claim 3
Dependent Claim
25 words
An image tube as claimed in claim 1, in which the extraction electrode is spaced between about 1 mm. and 3 mm. from the photocathode.
Claim 4
Dependent Claim
22 words
An image tube as claimed in claim 1, in which the source of positive voltage is of the order of 1 kV.
Claim 5
Dependent Claim
23 words
An image tube as claimed in claim 1, in which the deflection electrode means comprise at least one pair of strip line electrodes.
Claim 6
Dependent Claim
33 words
An image tube as claimed in claim 4, in which the Deflection electrode means comprises two pairs of strip line electrodes mounted to provide two deflecting electric fields at right-angles to each other.
Claim 7
Dependent Claim
78 words
An image tube streak camera comprising an image tube as claimed in claim 1, a source of ultra-short light pulses, means providing an image of said pulses at the photocathode of the image tube, voltage generating means connected to said deflection electrode means and providing a ramp voltage thereto, means synchronising said ramp voltage with passage of the photoelectrons through the deflection electrode means, and an image intensifier positioned to receive the stream image from the image tube.
Claim 8
Dependent Claim
24 words
A camera as claimed in claim 6, wherein the voltage generating means comprises a spark gap triggered by the pulses from the light source.
Claim 9
Dependent Claim
37 words
A camera as claimed in claim 6, wherein the voltage generating means comprises a circuit including a gas discharge tube triggered by pulses from a transistor operative in avalanche mode and receiving pulses from the light source.
Claim 10
Dependent Claim
21 words
A camera as claimed in claim 6, wherein the ramp voltage has a rise time of the order of one nanosecond.
Claim 11
Dependent Claim
64 words
A camera as claimed in claim 6, in which the image tube deflection electrode means comprises two pairs of electrodes with respective pairs at right-angles to each other, and in which said pairs of electrodes are connected to the voltage generating means in phased relationship to create two mutually perpendicular pulsed electric fields within the image tube thereby to provide a continuous streak record.
Claim 12
Dependent Claim
14 words
A camera as claimed in claim 6, wherein the light source is a laser.
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) | 1976-09-24 | 1977-03-26 | 1977-09-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-09-24 | 1981-03-26 | 1981-09-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-09-24 | 1985-03-26 | 1985-09-25 | $7700.00 | Window Closed / Lapsed |