Patent US4497540A successfully refreshed from Google Patents.
US4497540A
Expired / Lapsed
US
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Optical system
Assignee: National Aeronautics and Space Administration
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Filing: 1983-03-23
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Granted: 1985-02-05
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Expires: 2003-03-23
Abstract
Abstract Disclosed is an optical system used in a spacecraft to observe a remote surface and provide a spatial and spectral image of this surface. The optical system includes aspheric and spherical mirrors aligned to focus at a first focal plane an image of the surface, and a mirror at this first focal plane which reflects light back on to the spherical mirror. This spherical mirror collimates the light and directs it through a prism which disperses it. The dispersed light is then focused on an array of light responsive elements disposed at a second focal plane. The prism is designed such that it disperses light into components of different wavelengths, with the components of shorter wavelengths being dispersed more than the components of longer wavelengths to present at the second focal plane a distribution pattern in which preselected groupings of the components are dispersed over essentially equal spacing intervals.
Inventors
- 👤 James B. Breckinridge
- 👤 Norman A. Page
- 👤 Roland V. Shack
- 👤 Robert R. Shannon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 01:19
CPC Classifications
G; G01; G01J; G01J3/00; G01J3/12; G01J3/14; G01J3/28; G01J3/2803; G01J3/2823; G02; G02B; G02B17/00; G02B17/02; G02B17/06; G02B17/0605; G02B17/0615; G01J3/02; G01J3/0205; G01J3/0208
Claims Analysis
Total Claims: 36
Claim 1
Independent Claim
276 words
An optical system adapted to be used at elevations high above a surface and for forming a spectral and spatial image of the surface, comprising: entrance aperture means through which light from the surface enters the system; first means for focusing light passing through the entrance aperture means on a first focal plane within the system, said first means including aspheric mirror means and spherical mirror means in the optical path between the entrance aperture means and the first focal plane, said aspheric and spherical mirror means aligned relative to each other and the entrance aperture means so that the light passing through the entrance aperture means first strikes the aspheric mirror means which directs this light to a first segment of the spherical mirror means, and wherein said spherical mirror means is aligned and shaped so that said light reflects off the first segment and is focused at the first focal plane to form a spatial image of said surface; and second means for providing a spectral image of the surface and for focusing this image at a second focal plane within the system, including mirror means at the first focal plane for reflecting light from the first focal plane to a second segment of the spherical mirror means, with the light reflecting from said second segment being substantially collimated, dispersing means in the optical path between the second focal plane and the spherical mirror means for dispersing the light into a spectrum of different wavelengths, and means for focusing the light at different wavelengths exiting the dispersing means at the second focal plane to form thereat a spectral and spatial image of said surface.
Claim 2
Dependent Claim
276 words
An optical system adapted to be used at elevations high above a surface and for forming a spectral and spatial image of the surface, comprising: entrance aperture means through which light from the surface enters the system; first means for focusing light passing through the entrance aperture means on a first focal plane within the system, said first means including aspheric mirror means and spherical mirror means in the optical path between the entrance aperture means and the first focal plane, said aspheric and spherical mirror means aligned relative to each other and the entrance aperture means so that the light passing through the entrance aperture means first strikes the aspheric mirror means which directs this light to a first segment of the spherical mirror means, and wherein said spherical mirror means is aligned and shaped so that said light reflects off the first segment and is focused at the first focal plane to form a spatial image of said surface; and second means for providing a spectral image of the surface and for focusing this image at a second focal plane within the system, including mirror means at the first focal plane for reflecting light from the first focal plane to a second segment of the spherical mirror means, with the light reflecting from said second segment being substantially collimated, dispersing means in the optical path between the second focal plane and the spherical mirror means for dispersing the light into a spectrum of different wavelengths, and means for focusing the light at different wavelengths exiting the dispersing means at the second focal plane to form thereat a spectral and spatial image of said surface.
Claim 3
Dependent Claim
55 words
The optical system of claim 1 wherein the aspheric mirror means is tilted with respect to the axis of symmetry of the system so that there is an angle of from about 1.5 to about 5.0 degrees between the reflecting surface of the aspheric mirror means and a line perpendicular to the axis of symmetry.
Claim 4
Dependent Claim
22 words
The optical system of claim 1 wherein the first and second focal planes are adjacent each other in the same geometric plane.
Claim 5
Dependent Claim
13 words
The optical system of claim 1 wherein the first focal plane is spherical.
Claim 6
Dependent Claim
27 words
The optical system of claim 4 wherein the radius of curvature of the first focal plane is one-half the radius of curvature of the spherical mirror means.
Claim 7
Dependent Claim
59 words
The optical system of claim 1 wherein the means for focusing the light at the second focal plane include the spherical mirror means and a reflective surface which directs light onto a third segment of the spherical mirror means, said third segment reflecting the light onto the second focal plane and focusing this light at said second focal plane.
Claim 8
Dependent Claim
49 words
The optical system of claim 6 wherein the reflective surface is an aspherical mirror adjacent the dispersing means such that light first passes through the dispersing means, strikes the aspherical mirror, which then reflects it back through the dispersing means to the third segment of the spherical mirror means.
Claim 9
Dependent Claim
26 words
The optical system of claim 7 wherein there is a generally flat mirror disposed in the optical path between the prism and the spherical mirror means.
Claim 10
Dependent Claim
13 words
The optical system of claim 6 wherein the dispersing means is a prism.
Claim 11
Dependent Claim
191 words
An optical system adapted to be used at elevations high above a surface to form a spectral and spatial image of the surface, comprising: aperture means through which light from the surface enters the system as essentially parallel rays; first means for focusing the light entering the aperture means at a first focal plane having a curved surface corresponding to a convex segment of a sphere, said first means employing only stationary mirror means as the optical elements for focusing the light at said first focal plane; second means for focusing light at a second focal plane having a curved surface corresponding to a convex segment of a sphere, said second means employing only stationary mirror means as the optical elements to reflect the light from the first focal plane to the second focal plane as substantially collimated light along a predetermined optical path, and light dispersing means along the optical path for dispersing said collimated light as a spectrum of different wavelengths so that light of different wavelengths is focused at the second focal plane to form a spectral and spatial image of said surface at the second focal plane.
Claim 12
Dependent Claim
191 words
An optical system adapted to be used at elevations high above a surface to form a spectral and spatial image of the surface, comprising: aperture means through which light from the surface enters the system as essentially parallel rays; first means for focusing the light entering the aperture means at a first focal plane having a curved surface corresponding to a convex segment of a sphere, said first means employing only stationary mirror means as the optical elements for focusing the light at said first focal plane; second means for focusing light at a second focal plane having a curved surface corresponding to a convex segment of a sphere, said second means employing only stationary mirror means as the optical elements to reflect the light from the first focal plane to the second focal plane as substantially collimated light along a predetermined optical path, and light dispersing means along the optical path for dispersing said collimated light as a spectrum of different wavelengths so that light of different wavelengths is focused at the second focal plane to form a spectral and spatial image of said surface at the second focal plane.
Claim 13
Dependent Claim
56 words
The optical system of claim 10 wherein the first means includes aspheric mirror means tilted with respect to the axis of symmetry of the system so that there is an angle of from about 1.5 to 5.0 degrees between the reflecting surface of the aspheric mirror means and a line perpendicular to the axis of symmetry.
Claim 14
Dependent Claim
26 words
The optical system of claim 10 wherein the stationary mirror means in both the first means and the second means are adapted to minimize spherical aberration.
Claim 15
Dependent Claim
38 words
The optical system of claim 12 wherein the stationary mirror means include at least two aspherical mirrors, one in the optical path between the aperture means and the first focal plane and the other adjacent the aperture means.
Claim 16
Dependent Claim
38 words
The optical system of claim 10 wherein the aperture means has an area defined by a segment of a circle on a cord wherein the area is less than 50 percent of the total area of the circle.
Claim 17
Dependent Claim
26 words
The optical system of claim 10 wherein a spherical mirror is employed to reflect light onto both the first focal plane and the second focal planes.
Claim 18
Dependent Claim
20 words
The optical system of claim 15 wherein the spherical mirror is disposed along the optical path between two aspheric mirrors.
Claim 19
Dependent Claim
54 words
The optical system of claim 16 wherein the light dispersing means is a prism that is disposed along the optical path between one of the aspheric mirrors and the spherical mirror, with a flat reflective surface disposed between the spherical mirror and the prism on the side of the prism opposite the aspheric mirror.
Claim 20
Dependent Claim
162 words
An optical system having a wide field of view and adapted to be used at elevations high above a surface to form, without the aid of lenses, a spectral and spatial image of the surface, comprising: aperture means through which light from the surface enters the system as substantially parallel rays; first mirror means for focusing the light entering the pupil means at a first focal plane; means for reflecting the light focused at the first focal plane along an optical path to a second focal plane; means, along said optical path in advance of said second focal plane, for collimating the light; means, along said optical path between said means for collimating and said second focal plane, for dispersing the collimated light into a spectrum of different wavelengths; and means, between the dispersing means and the second focal plane, for focusing light of different wavelengths at said second focal plane to form a spectral and spatial light image of said surface.
Claim 21
Dependent Claim
162 words
An optical system having a wide field of view and adapted to be used at elevations high above a surface to form, without the aid of lenses, a spectral and spatial image of the surface, comprising: aperture means through which light from the surface enters the system as substantially parallel rays; first mirror means for focusing the light entering the pupil means at a first focal plane; means for reflecting the light focused at the first focal plane along an optical path to a second focal plane; means, along said optical path in advance of said second focal plane, for collimating the light; means, along said optical path between said means for collimating and said second focal plane, for dispersing the collimated light into a spectrum of different wavelengths; and means, between the dispersing means and the second focal plane, for focusing light of different wavelengths at said second focal plane to form a spectral and spatial light image of said surface.
Claim 22
Dependent Claim
58 words
The optical system of claim 18 wherein the first mirror means includes aspheric mirror means tilted with respect to the axis of symmetry of the system so that there is an angle of from about 1.5 to about 5.0 degrees between the reflecting surface of the aspheric mirror means and a line perpendicular to the axis of symmetry.
Claim 23
Dependent Claim
13 words
The optical system of claim 18 wherein the dispersing means is a prism.
Claim 24
Dependent Claim
79 words
The optical system of claim 20 wherein the prism includes at least two light diffraction elements interfacing in a predetermined relationship such that, when light passes through the elements, it is dispersed into components of different wavelengths, with the components of shorter wavelengths being dispersed more than the components of longer wavelength to present to a receiving surface a distribution pattern in which preselected groupings of the components of differing wavelengths will be dispersed over essentially equal spacing intervals.
Claim 25
Dependent Claim
17 words
The optical system of claim 21 wherein the two light diffraction elements are of different chemical composition.
Claim 26
Dependent Claim
46 words
The optical system of claim 18 including dichroic mirror means along the optical path between the collimating means and the dispersing means which direct the infrared components of the light onto a different portion of the second focal plane than the other components of the light.
Claim 27
Dependent Claim
22 words
The optical system of claim 18 including spherical mirror means which reflect light onto both the first and second focal planes simultaneously.
Claim 28
Dependent Claim
32 words
The optical system of claim 24 wherein collimated light is reflected from the surface of the spherical mirror means onto a flat mirror which reflects said collimated light into the dispersing means.
Claim 29
Dependent Claim
50 words
The optical system of claim 25 including mirror means adjacent the dispersing means which reflect light exiting the dispersing means back through the dispersing means onto the flat mirror, which in turn reflects the light onto the spherical mirror means which in turn reflects it onto the second focal plane.
Claim 30
Dependent Claim
38 words
The optical system of claim 26 wherein the aperture means has an area defined by a segment of a circle on a cord, wherein the area is less than 50 percent of the total area of the circle.
Claim 31
Dependent Claim
21 words
The optical system of claim 25 wherein the spherical mirror means is disposed along the optical path between two aspheric mirrors.
Claim 32
Dependent Claim
16 words
The optical system of claim 18 having a field of view in excess of about 30°.
Claim 33
Dependent Claim
18 words
The optical system of claim 18 wherein the field of view is between about 2° and about 60°.
Claim 34
Dependent Claim
25 words
The optical system of claim 18 wherein the first focal plane and the second focal plane are adjacent each other in the same geometric plane.
Claim 35
Dependent Claim
206 words
In a space craft, an optical system having a field of view of at least 30° and adapted to focus light from the surface of object in space onto a light responsive surface of a detecting system carried by the spacecraft, said optical system including aperture means in the spacecraft through which light from the surface enters the system, said aperture means having an area defined by a segment of a circle on a cord wherein the area is less than 50 percent of the total area of the circle, and means for focusing light passing through the aperture means on the light responsive surface, said focusing means including aspheric mirror means and spherical mirror means in the optical path between the aperture means and the first focal plane, said aspheric mirror means and said spherical mirror means being aligned relative to each other and the aperture means so that the light passing through the aperture means first strikes the aspheric mirror means which directs this light to the spherical mirror means, and said spherical mirror means being aligned and shaped so that said light reflects off the first segment and is focused at the first focal plane to form a spatial image of said surface.
Claim 36
Dependent Claim
206 words
In a space craft, an optical system having a field of view of at least 30° and adapted to focus light from the surface of object in space onto a light responsive surface of a detecting system carried by the spacecraft, said optical system including aperture means in the spacecraft through which light from the surface enters the system, said aperture means having an area defined by a segment of a circle on a cord wherein the area is less than 50 percent of the total area of the circle, and means for focusing light passing through the aperture means on the light responsive surface, said focusing means including aspheric mirror means and spherical mirror means in the optical path between the aperture means and the first focal plane, said aspheric mirror means and said spherical mirror means being aligned relative to each other and the aperture means so that the light passing through the aperture means first strikes the aspheric mirror means which directs this light to the spherical mirror means, and said spherical mirror means being aligned and shaped so that said light reflects off the first segment and is focused at the first focal plane to form a spatial image of said surface.
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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) | 1988-02-05 | 1988-08-06 | 1989-02-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-02-05 | 1992-08-06 | 1993-02-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-02-05 | 1996-08-06 | 1997-02-05 | $7700.00 | Window Closed / Lapsed |