US3730626A
Expired / Lapsed
US
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Monochromators with concave spherical gratings
Assignee: Centre National d'Études Spatiales
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Filing: 1972-02-11
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Granted: 1973-05-01
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Expires: 1992-02-11
Abstract
Abstract This invention relates to a monochromator with a rotating concave spherical grating in which the source-to-grating distance L is equal to
Inventors
- 👤 P Cruvellier
- 👤 M Duban
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 04:19
CPC Classifications
G; G01; G01J; G01J3/00; G01J3/12; G01J3/18
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
191 words
A monochromator comprising a fixed inlet slit, a fixed outlet slit and a concave spherical grating rotatable about a fixed axis which is parallel to the slits and to the lines of the grating, said axis passing through the apex of the grating, wherein the distance L from the inlet slit to the grating satisfies the relationship L ( 2R sin phi cos im)/( sin phi -(k lambda m/aa) cos rm) where phi is angle of deviation of the light beam through the grating, R is the radius of curvature of the grating, lambda m is the mean wavelength of the working spectral range, im and rm are the angles of incidence and of diffraction respectively for m in relation to the perpendicular at the apex of the grating, a is the pitch of the grating and k is the order of the operative procedure; the angle phi being selected to be less than 40* but at least equal to 29 (k lambda m/a) where k, lambda m and a are as defined above, m and a being expressed in the same units and the value of phi being in degrees.
Claim 2
Dependent Claim
191 words
A monochromator comprising a fixed inlet slit, a fixed outlet slit and a concave spherical grating rotatable about a fixed axis which is parallel to the slits and to the lines of the grating, said axis passing through the apex of the grating, wherein the distance L from the inlet slit to the grating satisfies the relationship L ( 2R sin phi cos im)/( sin phi -(k lambda m/aa) cos rm) where phi is angle of deviation of the light beam through the grating, R is the radius of curvature of the grating, lambda m is the mean wavelength of the working spectral range, im and rm are the angles of incidence and of diffraction respectively for m in relation to the perpendicular at the apex of the grating, a is the pitch of the grating and k is the order of the operative procedure; the angle phi being selected to be less than 40* but at least equal to 29 (k lambda m/a) where k, lambda m and a are as defined above, m and a being expressed in the same units and the value of phi being in degrees.
Claim 3
Dependent Claim
12 words
A monochromator according to claim 1, wherein phi is less than 30*.
Claim 4
Dependent Claim
45 words
A monochromator according to claim 1, wherein the outlet slit is arranged midway between the position of the tangential focal length for m and that of the tangential focal length for light whose wavelength is at one of the limits of the working spectral range.
Claim 5
Dependent Claim
38 words
A monochromator according to claim 1, in combination with a like second monochromator, said first and second monochromators constituting a double monochromator and the outlet slit of the first monochromator constituting the inlet slit of the second monochromator.
Claim 6
Dependent Claim
48 words
A double monochromator according to claim 4, wherein the outlet slits are each arranged midway between the position of the tangential focal length for lambda m and that of the tangential focal length for light whose wavelength is at one of the limits of the working spectral range.
References Cited (Backward Citations)
US2948184A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-04-30 | 1976-10-30 | 1977-05-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-30 | 1980-10-30 | 1981-05-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-30 | 1984-10-30 | 1985-05-01 | $7700.00 | Window Closed / Lapsed |