US5274435A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Grating monochromators and spectrometers based on surface normal rotation
Assignee: Individual
•
Filing: 1992-02-26
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Granted: 1993-12-28
•
Expires: 2012-02-26
Abstract
Abstract An optical system and method comprising a diffraction grating which rotates about its surface normal to change the magnitude of the wavelength diffracted to an image location. At grazing incidence, such a rotation is determined to maintain the diffracted image in focus over a wide range in scanned wavelength. Monochromator and spectrometer embodiments include plane and curved surface gratings with both classical and varied-spaced groove patterns, and a variety of illumination geometries. In the simplest case, a grazing incidence monochromator is constructed in which a self-focusing classical spherical grating scans the value in wavelength which is transmitted between fixed slits located on the Rowland circle of the grating. The diffracted image remains in perfect focus over two octaves in wavelength at high efficiency, with both entrance and exit slits fixed in position, and the radiation aperture is constant.
Inventors
- 👤 Michael C. Hettrick
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 06:21
CPC Classifications
G; G02; G02B; G02B5/00; G02B5/18; G02B5/1861; G01; G01J; G01J3/00; G01J3/12; G01J3/18; G01J3/189; G01J3/20; G21; G21K; G21K1/00; G21K1/06; G21K2201/00; G21K2201/06; G21K2201/064
Claims Analysis
Total Claims: 60
Claim 1
Independent Claim
92 words
A method for selecting wavelength comprising the steps of: a) providing a source of radiation consisting of a plurality of wavelengths; b) providing a grating having a surface containing a plurality of diffracting elements, where said surface is reflective to said radiation; c) providing means for rotating said grating about an axis which is substantially normal to said surface; where said surface is disposed to receive said radiation and where said means for rotating said grating causes a desired narrow band of said wavelengths to propagate to a restricted region of space.
Claim 2
Independent Claim
92 words
A method for selecting wavelength comprising the steps of: a) providing a source of radiation consisting of a plurality of wavelengths; b) providing a grating having a surface containing a plurality of diffracting elements, where said surface is reflective to said radiation; c) providing means for rotating said grating about an axis which is substantially normal to said surface; where said surface is disposed to receive said radiation and where said means for rotating said grating causes a desired narrow band of said wavelengths to propagate to a restricted region of space.
Claim 3
Dependent Claim
14 words
The method of claim 1, in which said diffracting elements are substantially parallel grooves.
Claim 4
Dependent Claim
13 words
The method of claim 2, in which said substantially parallel grooves are straight.
Claim 5
Dependent Claim
13 words
The method of claim 2, in which said substantially parallel grooves are concentric.
Claim 6
Dependent Claim
16 words
The method of claim 2, in which substantially parallel grooves have substantially similar radii of curvature.
Claim 7
Dependent Claim
11 words
The method of claim 1, in which said radiation is electromagnetic.
Claim 8
Dependent Claim
12 words
The method of claim 6, in which said surface is substantially planar.
Claim 9
Dependent Claim
11 words
The method of claim 6, in which said surface is concave.
Claim 10
Dependent Claim
11 words
The method of claim 8, in which said surface is spherical.
Claim 11
Dependent Claim
11 words
The method of claim 8, in which said surface is aspherical.
Claim 12
Dependent Claim
11 words
The method of claim 6, in which said surface is convex.
Claim 13
Dependent Claim
90 words
The method of claim 1, in which said means for rotating said grating comprise a bar which is rigidly connected to said grating, said bar and grating rotated about said grating surface normal by a planar surface which is in contact with a spherical member attached to the end of said bar, said planar surface being translated by equal distances as said bar and grating are rotated by equal changes in the cosine of the angle made by said diffracting elements relative to the unrotated orientation of said diffracting elements.
Claim 14
Dependent Claim
58 words
An optical system comprising: a) a grating comprising a surface containing a plurality of diffracting elements, where said surface is reflective to radiation; b) means for rotating said grating about an axis which is substantially normal to said surface; c) means for selecting a plurality of wavelengths of said radiation following reflection of said radiation by said surface.
Claim 15
Dependent Claim
58 words
An optical system comprising: a) a grating comprising a surface containing a plurality of diffracting elements, where said surface is reflective to radiation; b) means for rotating said grating about an axis which is substantially normal to said surface; c) means for selecting a plurality of wavelengths of said radiation following reflection of said radiation by said surface.
Claim 16
Dependent Claim
13 words
The optical system of claim 13, in which said radiation is electromagnetic radiation.
Claim 17
Dependent Claim
13 words
The optical system of claim 14, in which said surface is substantially planar.
Claim 18
Dependent Claim
12 words
The optical system of claim 14, in which said surface is concave.
Claim 19
Dependent Claim
12 words
The optical system of claim 14, in which said surface is convex.
Claim 20
Dependent Claim
16 words
The optical system of claim 15, in which said electromagnetic radiation is divergent onto said surface.
Claim 21
Dependent Claim
27 words
The optical system of claim 18, in which said diffracting elements are substantially parallel grooves spaced from one another by unequal distances as measured on said surface.
Claim 22
Dependent Claim
16 words
The optical system of claim 15, in which said electromagnetic radiation is convergent onto said surface.
Claim 23
Dependent Claim
16 words
The optical system of claim 15, in which said electromagnetic radiation is collimated onto said surface.
Claim 24
Dependent Claim
16 words
The optical system of claim 16, in which said electromagnetic radiation is divergent onto said surface.
Claim 25
Dependent Claim
16 words
The optical system of claim 16, in which said electromagnetic radiation is convergent onto said surface.
Claim 26
Dependent Claim
16 words
The optical system of claim 16, in which said electromagnetic radiation is collimated onto said surface.
Claim 27
Dependent Claim
12 words
The optical system of claim 22, in which said surface is spherical.
Claim 28
Dependent Claim
86 words
The optical system of claim 25, in which said diffracting elements are substantially parallel grooves spaced from each other by equal distances as projected on a plane tangent to said surface, in which the source of said radiation is placed on a circle which is tangent to said plane, said circle having a diameter equal to the radius of curvature of said surface, where said means for selecting a plurality of wavelengths comprise an exit slit placed on said circle, said optical system being a monochromator.
Claim 29
Dependent Claim
27 words
The optical system of claim 26, in which said radiation is incident to said tangent plane to said surface at an angle of less than 20 degrees.
Claim 30
Dependent Claim
14 words
The optical system of claim 27, in which said source is an entrance slit.
Claim 31
Dependent Claim
32 words
The optical system of claim 25, in which said diffracting elements are substantially parallel grooves spaced from each other by unequal distances as projected on a plane tangent to said grating surface.
Claim 32
Dependent Claim
27 words
The optical system of claim 29, in which said radiation is incident to said tangent plane to said surface at an angle of less than 20 degrees.
Claim 33
Dependent Claim
38 words
The optical system of claim 30, in which said means for selecting a plurality of wavelengths comprise a detection surface placed in the path of said radiation following reflection by said grating, said optical system being a spectrometer.
Claim 34
Dependent Claim
32 words
The optical system of claim 31, additionally comprising an entrance slit placed to transmit said radiation, such that said radiation passes along a straight line through said slit and strikes said grating.
Claim 35
Dependent Claim
30 words
The optical system of claim 32, in which the distance from said grating to said detection surface is substantially equal to the distance from said grating to said entrance slit.
Claim 36
Dependent Claim
33 words
The optical system of claim 19, in which said unequal distances are determined so as to diffract said divergent radiation to a substantial focus at said means for selecting a plurality of wavelengths.
Claim 37
Dependent Claim
38 words
The optical system of claim 24, in which said surface is spherical, and in which said diffraction elements are substantially parallel grooves spaced from one another by equal distances as projected on a plane tangent to said surface.
Claim 38
Dependent Claim
35 words
The optical system of claim 35, where said means for selecting a plurality of wavelengths comprise an exit slit placed to transmit said radiation following reflection by said grating, said optical system being a monochromator.
Claim 39
Dependent Claim
35 words
The optical system of claim 20, where said means for selecting a plurality of wavelengths comprise an exit slit placed to transmit said radiation following reflection by said grating, said optical system being a monochromator.
Claim 40
Dependent Claim
15 words
The optical system of claim 37, in which said diffracting elements are substantially parallel grooves.
Claim 41
Dependent Claim
24 words
The optical system of claim 38, in which said parallel grooves are spaced from each other by equal distances as measured on said surface.
Claim 42
Dependent Claim
24 words
The optical system of claim 38, in which said parallel grooves are spaced from each other by unequal distances as measured on said surface.
Claim 43
Dependent Claim
41 words
The optical system of claim 40, in which the distance from the grating to said exit slit is substantially equal to the distance from said grating to the point of convergence of said electromagnetic radiation which is convergent onto said surface.
Claim 44
Dependent Claim
31 words
The optical system of claim 21, in which said diffracting elements are substantially parallel grooves spaced from one another by equal distances as projected on a plane tangent to said surface.
Claim 45
Dependent Claim
48 words
The optical system of claim 42, in which said means for selecting a plurality of wavelengths comprise 1) a camera mirror placed in the path of said radiation following reflection by said grating, and 2) an exit slit placed to transmit said radiation following reflection by said mirror.
Claim 46
Dependent Claim
31 words
The optical system of claim 21, in which said diffracting elements are substantially parallel grooves spaced from one another by unequal distances as projected on a plane tangent to said surface.
Claim 47
Dependent Claim
24 words
The optical system of claim 27, in which said exit slit is fixed in position as said grating is rotated by said rotation means.
Claim 48
Dependent Claim
24 words
The optical system of claim 28, in which said entrance slit is fixed in position as said grating is rotated by said rotation means.
Claim 49
Dependent Claim
63 words
An optical system comprising: a) a first grating, comprising a surface containing a plurality of diffracting elements, where said surface is reflective to radiation; b) a second grating, comprising a surface containing a plurality of diffracting elements, where said surface is reflective to radiation; c) means for co-rotating said first and second gratings about axes which are substantially normal to their respective surfaces.
Claim 50
Dependent Claim
63 words
An optical system comprising: a) a first grating, comprising a surface containing a plurality of diffracting elements, where said surface is reflective to radiation; b) a second grating, comprising a surface containing a plurality of diffracting elements, where said surface is reflective to radiation; c) means for co-rotating said first and second gratings about axes which are substantially normal to their respective surfaces.
Claim 51
Dependent Claim
23 words
The optical system of claim 47, in which said radiation is electromagnetic radiation, and in which said diffracting elements are substantially parallel grooves.
Claim 52
Dependent Claim
31 words
The optical system of claim 48, in which said surface of said second grating is identical in shape and in location of said grooves to said surface of said first grating.
Claim 53
Dependent Claim
18 words
The optical system of claim 49, in which said surface of said first grating is a concave sphere.
Claim 54
Dependent Claim
25 words
The optical system of claim 50, in which said parallel grooves are equally spaced from one another as projected on plane tangent to said surface.
Claim 55
Dependent Claim
13 words
The optical system of claim 49, in which said surface is a plane.
Claim 56
Dependent Claim
24 words
The optical system of claim 52, in which said parallel grooves are spaced from one another by unequal distances as measured on said plane.
Claim 57
Dependent Claim
24 words
The optical system of claim 51, additionally comprising at least one slit placed to transmit said electromagnetic radiation following reflection by said second grating.
Claim 58
Dependent Claim
24 words
The optical system of claim 53, additionally comprising at least one slit placed to transmit said electromagnetic radiation following reflection by said second grating.
Claim 59
Dependent Claim
17 words
The optical system of claim 49, in which said electromagnetic radiation is collimated by said first grating.
Claim 60
Dependent Claim
31 words
The optical system of claim 49, in which said electromagnetic radiation is focused by said first grating to a point located substantially midway between said first grating and said second grating.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-12-27 | 1997-06-28 | 1997-12-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-12-27 | 2001-06-28 | 2001-12-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-12-27 | 2005-06-28 | 2005-12-28 | $7700.00 | Window Closed / Lapsed |