OPTICAL BAFFLE

Abstract

An optical baffle is provided that maximizes light reflection and absorption and, thus, enables a spacecraft camera to capture images of extremely faint objects, such as stars, while illuminated by a very bright source, such as the sun. The optical baffle may be manufactured by additive manufacturing techniques and unique materials to create unique geometry and very absorbent surfaces to trap light.

Claims

1. A device for gathering light signals, comprising: a first segment defined by a proximal end and a distal end spaced from the proximal end, which defines the length of the first segment, the first segment also having an inner surface with a plurality of vanes extending into an interior volume of the first segment, wherein each of the plurality of vanes are interconnected to the inner surface at a vane angle; a second segment interconnected proximal end to the second surface of the first segment; a detector situated within the second segment adjacent; and at least one lens situated between the first segment and the detector.

2. The device of claim 1, wherein the vane angle changes from one vane to the next vane as a function of a vane's location relative to the proximal end of the first segment.

3. The device of claim 1, wherein the plurality of vanes are defined by vane groups, wherein each vane in a vane group has the same vane angle.

4. The device of claim 1, wherein each vane of the plurality thereof has a rough surface texture.

5. The device of claim 1, wherein the interior surface and the plurality of vanes are coated with black anodize.

6. The device of claim 1, wherein the at least one lens comprises a first lens, a second lens, and a third lens.

7. The device of claim 1, wherein the first segment is frustoconical.

8. The device of claim 7, wherein a cross section of the first segment is generally square or rectangular.

9. The device of claim 1, wherein each vane of the plurality thereof comprises a ring with a first, outer end interconnected to the inner surface of the first segment and a second, inner end positioned within the interior volume of the first segment, each vane further comprising an upper surface that generally faces the distal end of the first segment and a lower surface that generally faces the second segment, and wherein the vane angle is defined as the angle between the lower surface of each vane and a corresponding imaginary planar surface that is normal to a longitudinal axis of the first segment.

10. The device of claim 9, wherein at least one vane angle is negative, wherein the lower surface is directed towards the second segment.

11. The device of claim 9, wherein the second end of each vane comprises a non-planar outer extent defined by the conjunction of the upper surface and lower surface of each vane.

12. The device of claim 9, wherein each vane of the plurality thereof includes cavities on the upper and lower surface thereof, and wherein the plurality of vanes possess internal voids.

13. The device of claim 9, wherein the upper surface of each vane includes a downward slopping portion, and the lower surface of each vane includes an upward slopping portion that meet to define an outer extent of each vane.

14. The device of claim 9, wherein the plurality of vanes is manufactured by a laser sintering process, whereby the first segment and the plurality of vanes are formed of discrete material layers.

15. The device of claim 14, wherein the layers are varied in width, wherein the inner surface of the first segment, the upper surfaces, and the lower surfaces of the plurality of vanes is consist of microscopic overhangs.

16. The device of claim 14, wherein the first segment and plurality of vanes are made of aluminum (Al) particles blended with aluminum oxide (Al.sub.2O.sub.3) particles in a concentration of between about 6% and 50%, wherein in the Al.sub.2O.sub.3 particles are later removed by etching.

17. A device for gathering light signals, comprising: a first segment defined by a proximal end and a distal end spaced from the proximal end, which defines the length of the first segment, the first segment also having an inner surface with a plurality of vanes extending therefrom, wherein each of the plurality of vanes are interconnected to the inner surface at a vane angle; a second segment interconnected to the proximal end of the first segment; a detector situated within the second segment; at least one lens situated within the second segment between the detector and the first segment; wherein each vane of the plurality thereof comprises a ring with a first, outer end interconnected to the inner surface of the first segment and a second, inner end, each vane further comprising an upper surface that generally faces the distal end of the first segment and a lower surface that generally faces the second segment, and wherein the vane angle is defined as the angle between the lower surface of each vane and a planar surface that normal to a longitudinal axis of the first segment; and wherein the vane angle changes from one vane to the next vane as a function of a vane's location relative to the proximal end of the first segment.

18. The device of claim 17, wherein at least one vane angle is negative, wherein the lower surface is directed towards the second segment.

19. The device of claim 17, wherein the upper surface of each vane includes a downward slopping portion, and the lower surface of each vane includes an upward slopping portion that meet to define an outer extent of each vane.

20. The device of claim 17, wherein the plurality of vanes is manufactured by a laser sintering process, whereby the first segment and the plurality of vanes are formed of discrete material layers, and wherein the layers are varied in width, wherein the inner surface of the first segment, the upper surfaces, and the lower surfaces of the plurality of vanes consist of microscopic overhangs.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and together with the general description of the invention given above and the detailed description of the drawings given below, explain the principles of these inventions.

[0023] FIG. 1 is a side elevation view of an optical baffle of one embodiment of the present invention interconnected to a lens barrel;

[0024] FIG. 2 is a top plan view of FIG. 1;

[0025] FIG. 3 is a cross-sectional view of FIG. 1;

[0026] FIG. 4 is a detailed view of FIG. 3; and

[0027] FIG. 5 is another detailed view of FIG. 3.

[0028] The following component list and associated numbering found in the drawings is provided to assist in the understanding of one embodiment of the present invention:

TABLE-US-00001 # Component 2 Optical Baffle 6 Detector 10 Lens barrel 14 Lens 16 Proximal end 18 Distal end 20 Aperture 22 Light 26 Wall 30 Inner surface 34 Outer surface 38 Vane 42 Edge surface 46 Field of view boundary 50 First end 54 Second end 58 Horizontal plane 60 Centerline 62 Outer surface 66 Inner surface 68 Chamfer 72 Overhang 76 Edge,

[0029] It should be understood that the drawings are not necessarily to scale. In certain instances, details which are not necessary for an understanding of the invention or which render other details difficult to perceive may have been omitted. It should be understood, of course, that the invention is not necessarily limited to the embodiments illustrated herein.

DETAILED DESCRIPTION

[0030] FIGS. 1-3 show an optical baffle 2 designed to minimize the amount of off-angle or bright light sensed by a detector 6. The baffle 2 is interconnected to a lens barrel 10 that houses a plurality of lenses 14. The baffle 2 of one embodiment of the present invention is frusto-conical, wherein a proximal end 16, which is interconnected to the lens barrel 10 has a smaller outer diameter then a distal end, which includes an aperture 20 that that captures light 22. The lens barrel 10 of one embodiment of the present invention accommodates three lenses 14 and the detector 6. Those of ordinary skill in the art will appreciate that the detector may be associated with a camera.

[0031] Referring now to FIGS. 3 and 4, the internal configuration of an optical baffle 2 of one embodiment of the present invention is shown. The baffle 2 generally consists of a wall 26 that has an inner surface 30 and an outer surface 34. A series of vanes 38 extend from the inner surface 30 into an interior volume of the baffle 2. Each vane ends in an edge surface 42 or a tip, which defines a field-of-view boundary 46. In operation, off-angle light 22 enters the optical baffle 2; in this example along arrow A. Thereafter, the light reflects off interior surfaces of the baffle and follows arrows B and C, and eventually contacts the detector 6. It is the goal of embodiments the present invention to minimize the amount and intensity of light that contacts the detector from off angled sources, i.e., light along arrow D. The light angles shown are for illustrative purposes only. In practice, the gathered light bounces in every direction and most of it is absorbed before striking the detector.

[0032] The vanes 38 have a first end 50, or route, interconnected to the inner surface 30 of the baffle wall 26 and a second end 54 that extends into the interior volume of the optical baffle 2. The vanes 38 are angled with respect to an imaginary horizontal plane 58 that is substantially parallel to a plane normal to the baffle centerline 60. The vane angle (0) may vary depending on the vane's location within the optical baffle 2. The vane angle, with respect to horizontal, may vary from 0 (i.e., horizontal) to a steep angle, (i.e., about 30 to 60). The angle may be different between adjacent baffles. The ideal angle is a function of the position of the vane within the baffle. In some embodiments, vanes near the aperture have a negative angle and vanes near the lens have a positive angle.

[0033] For example, in one embodiment of the present invention, the vane angle adjacent to the distal end 18 of the optical baffle is less than that of the vanes located closer to the lens barrel 10. This feature facilitates absorbing or deflecting unwanted light, wherein the majority of unwanted light does not reach the detector 6. One of ordinary skill in the art will appreciate that the vanes may be formed in groups with the same vane angle. In addition, it should be appreciated that the vane angle () may vary as a function of the distance from the distal end 18 of the optical baffle to the proximal end 16 of the optical baffle. Again, the vane angle could be negative ().

[0034] The vanes 38 follow the profile of the inner surface 30 of the optical baffle 2, which creates ring-shaped vanes. In one embodiment of the present invention, the interior surface of the optical baffle 2 has a generally square cross-section, as shown in FIG. 2. However, circular, semicircular, rectangular, oval, faceted (e.g., hexagonal, etc.), or triangular cross-sections are also contemplated. The second end 54 of the vanes 38 may define a plane or be noncontinuous, i.e., wavy, as shown in FIG. 3. The vanes may also be non-continuous and consist of adjacent vane segments follow the interior baffle profile.

[0035] The vanes 38 may also have a non-continuous edge 42. More specifically, as shown in FIG. 4, the edge 42 of at least one vane 38 includes an outer surface 62 and inner surface 66 that meet and define an edge 76. Here, the edge 76 is defined by the conjunction of a chamfer 68 that extends from a portion of the outer surface 62 and the edge surface 42 that extends upwardly from the inner surface 66. Depending on the vane angle, the surface provided by the chamfer 68 will generally correspond with the imaginary horizontal plane 58. As mentioned briefly above, the surfaces provided by the chamfer 68 reflect unwanted light upwardly towards the inner surface 66 of an adjacent vane 38.

[0036] As shown in FIG. 5, the optical baffle 2 may be formed of a sintering process that creates overhangs 72, inconsistencies, or voids on the baffle's inner surface 30 and/or the vane's inner surface 30 and/or outer surface 34. The overhangs disrupt the smooth surface of the optical baffle and its vanes and create obstructions that deflect or absorb the unwanted light 22.

[0037] Exemplary characteristics of embodiments of the present invention have been described. However, to avoid unnecessarily obscuring embodiments of the present invention, the preceding description may omit several known apparatus, methods, systems, structures, and/or devices one of ordinary skill in the art would understand are commonly included with the embodiments of the present invention. Such omissions are not to be construed as a limitation of the scope of the claimed invention. Specific details are set forth to provide an understanding of some embodiments of the present invention. It should, however, be appreciated that embodiments of the present invention may be practiced in a variety of ways beyond the specific detail set forth herein.

[0038] Modifications and alterations of the various embodiments of the present invention described herein will occur to those skilled in the art. It is to be expressly understood that such modifications and alterations are within the scope and spirit of the present invention, as set forth in the following claims. Further, it is to be understood that the invention(s) described herein is not limited in its application to the details of construction and the arrangement of components set forth in the preceding description or illustrated in the drawings. That is, the embodiments of the invention described herein are capable of being practiced or of being carried out in various ways. The scope of the various embodiments described herein is indicated by the following claims rather than by the foregoing description. And all changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope. It is intended to obtain rights which include alternative embodiments to the extent permitted, including alternate, interchangeable and/or equivalent structures, functions, ranges or steps to those claimed, whether or not such alternate, interchangeable and/or equivalent structures, functions, ranges or steps are disclosed herein, and without intending to publicly dedicate any patentable subject matter.

[0039] The foregoing disclosure is not intended to limit the invention to the form or forms disclosed herein. In the foregoing Detailed Description, for example, various features of the invention are grouped together in one or more embodiments for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the claimed inventions require more features than expressly recited. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single foregoing disclosed embodiment. Thus, the following claims are hereby incorporated into this Detailed Description, with each claim standing on its own as a separate preferred embodiment of the invention. Further, the embodiments of the present invention described herein include components, methods, processes, systems, and/or apparatus substantially as depicted and described herein, including various sub-combinations and subsets thereof. Accordingly, one of skill in the art will appreciate that it would be possible to provide for some features of the embodiments of the present invention without providing others. Stated differently, any one or more of the aspects, features, elements, means, or embodiments as disclosed herein may be combined with any one or more other aspects, features, elements, means, or embodiments as disclosed herein.