CA2050520A1 - Auxiliary shielding and focussing device for a telescope - Google Patents
Auxiliary shielding and focussing device for a telescopeInfo
- Publication number
- CA2050520A1 CA2050520A1 CA 2050520 CA2050520A CA2050520A1 CA 2050520 A1 CA2050520 A1 CA 2050520A1 CA 2050520 CA2050520 CA 2050520 CA 2050520 A CA2050520 A CA 2050520A CA 2050520 A1 CA2050520 A1 CA 2050520A1
- Authority
- CA
- Canada
- Prior art keywords
- telescope
- openings
- auxiliary shielding
- focussing device
- image
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Classifications
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
- G02B27/0018—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00 with means for preventing ghost images
Landscapes
- Telescopes (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
An auxiliary shielding and focusing device for a tele-scope is shown. The device is in the form of a lens cap which can be removably mounted over the light receiving front end of a telescope. The device has a generally flat surface and having two substantially equal size circular openings formed along a diameter therein. These openings are spaced equally from the respective immediately adjacent side along such diameter. The openings prevent the formation of stray light within the telescope and create a parallax effect for the image such that double images are formed when the telescope is out of focus, and the double images will merge into a single sharp image when it is in focus. The openings also inherently serve as a shielding means to reduce the size of the front lens opening of the telescope so as to reduce the brightness of a glaring image of high intensity as well as to increase the resolution of such image.
An auxiliary shielding and focusing device for a tele-scope is shown. The device is in the form of a lens cap which can be removably mounted over the light receiving front end of a telescope. The device has a generally flat surface and having two substantially equal size circular openings formed along a diameter therein. These openings are spaced equally from the respective immediately adjacent side along such diameter. The openings prevent the formation of stray light within the telescope and create a parallax effect for the image such that double images are formed when the telescope is out of focus, and the double images will merge into a single sharp image when it is in focus. The openings also inherently serve as a shielding means to reduce the size of the front lens opening of the telescope so as to reduce the brightness of a glaring image of high intensity as well as to increase the resolution of such image.
Description
J (~
This invention relates to an image enhancing device for a telescope, and more particularly for an auxiliary shielding and focussing device which may be mounted on an astronomical telescope to enhance the image viewed in such telescope as well as to facilitate the quick focussing of the telescope to obtain a precise sharp image.
High power telescopes such as astronomical telescopes are constructed of a lens mounted at the light receiving front end therein which receives the light from the object such as a star or planet to be viewed. The light after passing through the front lens is incident upon a concave primary mirror located at the rear of the telescope. The reflected light from the primary mirror is further reflected from a secondary mirror located adjacent to and behind the front lens so as to form the ir,lage of the object in the telescope. I'he object is viewed by adjusting the eyepiece of the telescope until a sharp image is formed.
In order to provide a sharp image, the primary mirror of the telescope must have a perfect reflective surface and curvature. ~owever, due to the size and diameter of the primary mirror, often a bad edge such as a rolled edge or turned down edge is present therein. Such turned down edge will in medium and high power telescopes cause the incoming light to scatter randomly within the telescope resulting in the loss of overall sharpness and subtle detail of the image.
The fine detail of the image is washed out by the scattered light. Such drawback can not be obviated by using a funct:ional shield such that shown in U.S. Patent No. 4,729,649 to Charles A. Thompson which provides a conical shield at the front end of the telescope. The conical shield is provided with a
This invention relates to an image enhancing device for a telescope, and more particularly for an auxiliary shielding and focussing device which may be mounted on an astronomical telescope to enhance the image viewed in such telescope as well as to facilitate the quick focussing of the telescope to obtain a precise sharp image.
High power telescopes such as astronomical telescopes are constructed of a lens mounted at the light receiving front end therein which receives the light from the object such as a star or planet to be viewed. The light after passing through the front lens is incident upon a concave primary mirror located at the rear of the telescope. The reflected light from the primary mirror is further reflected from a secondary mirror located adjacent to and behind the front lens so as to form the ir,lage of the object in the telescope. I'he object is viewed by adjusting the eyepiece of the telescope until a sharp image is formed.
In order to provide a sharp image, the primary mirror of the telescope must have a perfect reflective surface and curvature. ~owever, due to the size and diameter of the primary mirror, often a bad edge such as a rolled edge or turned down edge is present therein. Such turned down edge will in medium and high power telescopes cause the incoming light to scatter randomly within the telescope resulting in the loss of overall sharpness and subtle detail of the image.
The fine detail of the image is washed out by the scattered light. Such drawback can not be obviated by using a funct:ional shield such that shown in U.S. Patent No. 4,729,649 to Charles A. Thompson which provides a conical shield at the front end of the telescope. The conical shield is provided with a
2 ~
plurality of evenly spaced oval shaped openings. The shield is intended to shield out stray light from the ambient from entering into the telescope. It also prevents the formation of dew on the lens, which may interEere with the viewing oper-ation of the telescope. However, such shield can not prevent the formation of scattered stray light within the telescope due to the imperfection of the reflecting mirrors.
It is a principal object of the present invention to provide an auxiliary shielding device which may be readily adaptable on a telescope to eliminate the formation of scat-tered stray light within a telescope.
It is another object of the present invention to provide an auxiliary shielding device which is operative also as a focussing device for enhancing the precise and easy adjustment of the telescope to obtain the sharpest image obtainable.
It is another object of the present invention to provide an auxiliary shielding device operative for lncorporating selected light and colour filters thereon for various viewing purposes.
It is another object of the present invention to provide an auxlliary shielding devlce which can operate to reduce the luminosity of a bright image in a ~telescope as well as to increase its resolution.
It is still another object of the present invention to provide an auxiliary shielding device which can be readily and easily adapted to a telescope without necessitating any modification to be made in the telescope.
It is yet another object of the present invention to provide an auxiliary shielding and focussing device which is simple in construction and yet is highly efficient in opera-tion.
The auxilary shielding and focussing device comprises a circular disc having a substantially flat top surface and bottom surface. The bottom surface has a round periphery having a round slcirting flange formed therealong. The skirting flange extends downwardly from the bottom surface and is operative for removably mounting the disc to the light receiv-ing end of a telescope. Two openings, preferably circular openings~ are formed in the disc along a diameter therein. The openings are substantially equal in size and are spaced an equal distance from the respective immediately adjacent side of the disc along the diameter.
In drawings which illustrate embodiments of the invent-ion, Figure 1 is a schematic sectional side elevation view of an exemplary telescope showing its common general construction and the light paths therein.
Figure 2 is a schematic sectional side elevation view of the telescope shown in Figure I with an auxiliary shielding ~and focussing device provided over its light receiving end.
Figure 3 is a perspective bottom side elevation view of the auxiliary shielding and focussing device according to the present invention.
Figure 4 is a perspective top side elevation view ther-eof.
Figure 5 is a perspective top view of the auxiliary shielding and focussing device according to the present invention.
Figure 6 is a sectional side elevation view along section line VI-VI of Figure 5.
Figure 7 is a bottom perspective elevation view of the auxiliary shielding and focussing device according to the ~r~
present invention.
With reference to the drawings wherein like reference numerals designate corresponding parts in the several views, a telescope 10 having a light receiving lens 11 mounted at its front end 12, and a primary reflection mirror 13 provided at its rear end. Such telescope is commonly known as a Schmidt-Cassegrain telescope. It is shown as an example for the simplicity in illustrating the present invention. Light from a star or planet enters the telescope through its front end 12, and after passing through the receiving lens 11 is incident upon the primary mirror 13. The reflected light from the primary mirror 13 impinges upon the secondary mirror 14 located adjacent to and behind the receiving lens 11. The reflected light from the secondary mirror 14 forms the image at the focal point 15 within the telescope. The image may then be viewed by adjusting the eyepiece 16. The secondary mirror 14, in another common construction, such as in a Newtonian telescope, may be located close to but spaced from the receiv-ing lens 11 so that it directs the incident light from the primary mirror 13 to the eyepiece located at the side of the telescope. The principle of operation and desired results achieved according to the prPsent invention are the same for telescopes of such different constructions.
The sharpness of the image formed within the telescope 10 is highly dependent upon the reflective quality of the mirrors and particularly the primary mirror 13. The clarity of the image can be corrupted by the :incident light reflected from a turned down or rolled edge often existing in the primary mirror 13. Such turned down edge will in medium and high power telescopes scatter the incident light randomly within the telescope cavity resulting in the loss of sharpness and subtle ~J~ 2 ~
detail in the image. Usually, the rolled edge can have a dimension of about 1/16th of an inch wide in a common 8-inch or 10-inch compact portable telescope.
I have discovered that the problem of formation of scattering stray light within the telescope can be obviated by incorporating a lens cap like shield 20 over the light receiv-ing end of the telescope. The shield is in the form of a saucer 21 having a generally flat round disc body and having a generally flat top surface 22. Two openings 23 and 24, prefer-ably circular in shape, are formed along a diameter of thedisc and are equally spaced from the respective immediately adjacent peripheral side oE the disc along such a diameter.
The disc is provided with mounting means such as a skirting flange 25 along the periphery of the bottom surface of the disc so that the disc can be quickly and removably mounted over the light receiving end 12 of the telescope by interfer-ence fitting. Such simple mounting means does not require any modification to be made :in the telescope.
The shield 20 may be made of metal such as llght weight aluminum or a suitable durable plastic material.
As best shown in Figure 2, when the shield 20 is fitted over the light receiving end 12 of the telescope, the openings 23 and 24 will prevent the incident light from impinging upon any rolled edge in the primary mirror, thus eliminating the formation of stray reflected light from the primary mirror 13.
Furthermore, the separation of the two openings 23 and 24 over the light receiving end of the telescope inherently provides a paralla~ effect by forming double images of the object within the telescope when the telescope is out of focus. The double images will overlap and merge with each other into a single sharp image when the focus of the telescope is properly ~ J~
adjusted. Thus, the shield 20 also enhances the quick and precise adjustment of the focus of the telescope to achieve the sharpest image the lens system can provide. This desirable result is particulary noticeable as the power of the telescope increases resulting in providing a larger size image. Theref-ore, it is possible to adjust the focus of t'ne telescope in viewing a planet or moon without having to move annoyingly and painstakingly back and forth between a bright star and the planets, as in common practice, in order to assure that the sharpest image has been obtained.
Furthermore, the openings 23 and 24 inherently serve as a shield to reduce the size of the lens opening of the teles-cope. Such reduced lens opening is particularly advantageous in viewing a bright planet. It will reduce the glaring bright-ness of the image as well as will increase its resolutionsimilar to the effect of reducing the lens opening of a camera to achieve the same image effects.
~ ilters such as solar or lunar filters may be easily and quickly adapted at the openings 23 and 24 for viewing the sun and the moon. Also, colour filters of selected colours can be adapted to enhance the viewing of a planet having a predomin-ant colour, for example, red or orange filter for viewing Mars, yellow or blue filter for viewing Saturn, and blue or green filter for viewing Jupiter. Moreover, a different colour filter may be mounted in each one of the openings if desired for selected results.
While the invention has been particularly shown and described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invent;on.
For example, the openings 23 and 24 may be of other shapes than circular, and a plurality of such openings may be provi-ded on the shield for similar purposes.
plurality of evenly spaced oval shaped openings. The shield is intended to shield out stray light from the ambient from entering into the telescope. It also prevents the formation of dew on the lens, which may interEere with the viewing oper-ation of the telescope. However, such shield can not prevent the formation of scattered stray light within the telescope due to the imperfection of the reflecting mirrors.
It is a principal object of the present invention to provide an auxiliary shielding device which may be readily adaptable on a telescope to eliminate the formation of scat-tered stray light within a telescope.
It is another object of the present invention to provide an auxiliary shielding device which is operative also as a focussing device for enhancing the precise and easy adjustment of the telescope to obtain the sharpest image obtainable.
It is another object of the present invention to provide an auxiliary shielding device operative for lncorporating selected light and colour filters thereon for various viewing purposes.
It is another object of the present invention to provide an auxlliary shielding devlce which can operate to reduce the luminosity of a bright image in a ~telescope as well as to increase its resolution.
It is still another object of the present invention to provide an auxiliary shielding device which can be readily and easily adapted to a telescope without necessitating any modification to be made in the telescope.
It is yet another object of the present invention to provide an auxiliary shielding and focussing device which is simple in construction and yet is highly efficient in opera-tion.
The auxilary shielding and focussing device comprises a circular disc having a substantially flat top surface and bottom surface. The bottom surface has a round periphery having a round slcirting flange formed therealong. The skirting flange extends downwardly from the bottom surface and is operative for removably mounting the disc to the light receiv-ing end of a telescope. Two openings, preferably circular openings~ are formed in the disc along a diameter therein. The openings are substantially equal in size and are spaced an equal distance from the respective immediately adjacent side of the disc along the diameter.
In drawings which illustrate embodiments of the invent-ion, Figure 1 is a schematic sectional side elevation view of an exemplary telescope showing its common general construction and the light paths therein.
Figure 2 is a schematic sectional side elevation view of the telescope shown in Figure I with an auxiliary shielding ~and focussing device provided over its light receiving end.
Figure 3 is a perspective bottom side elevation view of the auxiliary shielding and focussing device according to the present invention.
Figure 4 is a perspective top side elevation view ther-eof.
Figure 5 is a perspective top view of the auxiliary shielding and focussing device according to the present invention.
Figure 6 is a sectional side elevation view along section line VI-VI of Figure 5.
Figure 7 is a bottom perspective elevation view of the auxiliary shielding and focussing device according to the ~r~
present invention.
With reference to the drawings wherein like reference numerals designate corresponding parts in the several views, a telescope 10 having a light receiving lens 11 mounted at its front end 12, and a primary reflection mirror 13 provided at its rear end. Such telescope is commonly known as a Schmidt-Cassegrain telescope. It is shown as an example for the simplicity in illustrating the present invention. Light from a star or planet enters the telescope through its front end 12, and after passing through the receiving lens 11 is incident upon the primary mirror 13. The reflected light from the primary mirror 13 impinges upon the secondary mirror 14 located adjacent to and behind the receiving lens 11. The reflected light from the secondary mirror 14 forms the image at the focal point 15 within the telescope. The image may then be viewed by adjusting the eyepiece 16. The secondary mirror 14, in another common construction, such as in a Newtonian telescope, may be located close to but spaced from the receiv-ing lens 11 so that it directs the incident light from the primary mirror 13 to the eyepiece located at the side of the telescope. The principle of operation and desired results achieved according to the prPsent invention are the same for telescopes of such different constructions.
The sharpness of the image formed within the telescope 10 is highly dependent upon the reflective quality of the mirrors and particularly the primary mirror 13. The clarity of the image can be corrupted by the :incident light reflected from a turned down or rolled edge often existing in the primary mirror 13. Such turned down edge will in medium and high power telescopes scatter the incident light randomly within the telescope cavity resulting in the loss of sharpness and subtle ~J~ 2 ~
detail in the image. Usually, the rolled edge can have a dimension of about 1/16th of an inch wide in a common 8-inch or 10-inch compact portable telescope.
I have discovered that the problem of formation of scattering stray light within the telescope can be obviated by incorporating a lens cap like shield 20 over the light receiv-ing end of the telescope. The shield is in the form of a saucer 21 having a generally flat round disc body and having a generally flat top surface 22. Two openings 23 and 24, prefer-ably circular in shape, are formed along a diameter of thedisc and are equally spaced from the respective immediately adjacent peripheral side oE the disc along such a diameter.
The disc is provided with mounting means such as a skirting flange 25 along the periphery of the bottom surface of the disc so that the disc can be quickly and removably mounted over the light receiving end 12 of the telescope by interfer-ence fitting. Such simple mounting means does not require any modification to be made :in the telescope.
The shield 20 may be made of metal such as llght weight aluminum or a suitable durable plastic material.
As best shown in Figure 2, when the shield 20 is fitted over the light receiving end 12 of the telescope, the openings 23 and 24 will prevent the incident light from impinging upon any rolled edge in the primary mirror, thus eliminating the formation of stray reflected light from the primary mirror 13.
Furthermore, the separation of the two openings 23 and 24 over the light receiving end of the telescope inherently provides a paralla~ effect by forming double images of the object within the telescope when the telescope is out of focus. The double images will overlap and merge with each other into a single sharp image when the focus of the telescope is properly ~ J~
adjusted. Thus, the shield 20 also enhances the quick and precise adjustment of the focus of the telescope to achieve the sharpest image the lens system can provide. This desirable result is particulary noticeable as the power of the telescope increases resulting in providing a larger size image. Theref-ore, it is possible to adjust the focus of t'ne telescope in viewing a planet or moon without having to move annoyingly and painstakingly back and forth between a bright star and the planets, as in common practice, in order to assure that the sharpest image has been obtained.
Furthermore, the openings 23 and 24 inherently serve as a shield to reduce the size of the lens opening of the teles-cope. Such reduced lens opening is particularly advantageous in viewing a bright planet. It will reduce the glaring bright-ness of the image as well as will increase its resolutionsimilar to the effect of reducing the lens opening of a camera to achieve the same image effects.
~ ilters such as solar or lunar filters may be easily and quickly adapted at the openings 23 and 24 for viewing the sun and the moon. Also, colour filters of selected colours can be adapted to enhance the viewing of a planet having a predomin-ant colour, for example, red or orange filter for viewing Mars, yellow or blue filter for viewing Saturn, and blue or green filter for viewing Jupiter. Moreover, a different colour filter may be mounted in each one of the openings if desired for selected results.
While the invention has been particularly shown and described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invent;on.
For example, the openings 23 and 24 may be of other shapes than circular, and a plurality of such openings may be provi-ded on the shield for similar purposes.
Claims (10)
1. An auxiliary shielding and focussing device for a teles-cope, comprising a generally cirular and flat disc means having a top surface and a bottom surface, adaptor means disposed in said bottom surface and operat-ive for mounting said disc means over a light receiving end of said telescope, at least two openings formed along a diameter of said disc means, said openings being substantially equal in size and being spaced a substantially equal distance from the respective immediately adjacent side of said disc means along said diameter.
2. An auxiliary shielding and focussing device as claimed in Claim 1 wherein said openings are circular in shape.
3. An auxiliary shielding and focussing device as claimed in Claim 2 wherein said adaptor means is a skirting flange formed along the periphery of said bottom surface, said skirting flange being operative for removably mounting said device to the light receiving end of said telescope.
4. An auxiliary shielding and focussing device as claimed in Claim 3 including light filter means mounted at said openings.
5. An auxiliary shielding and focussing device as claimed in Claim 4 wherein said filter means is a light screening filter.
6. An auxiliary shielding and focussing device as claimed in Claim 4 wherein said filter means is a light filter of a selected colour.
7. An auxiliary shielding and focussing device for a teles-cope, comprising a circular disc means having a substantially flat top surface and a substantially flat bottom surface, said bottom surface having a circular periphery, a circular skirting flange formed along said circular periphery and extending downwardly from said bottom surface, said skirting flange being operative for removably mounting said disc means over the light receiving end of said teles-cope, two circular openings formed along a diameter of said disc means, said openings being substantially equal in size and being spaced an equal distance from the respective immedi-ately adjacent side of said disc means along said diameter.
8. An auxiliary shielding and focussing device according to Claim 7 wherein said device is made of a metallic material.
9. An auxiliary shielding and focussing device according to Claim 7 wherein said device is made of a plastic material.
10. An auxiliary shielding and focussing device according to Claim 8 or 9 wherein said disc means and said skirting flange are integrally formed.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA 2050520 CA2050520A1 (en) | 1991-09-03 | 1991-09-03 | Auxiliary shielding and focussing device for a telescope |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA 2050520 CA2050520A1 (en) | 1991-09-03 | 1991-09-03 | Auxiliary shielding and focussing device for a telescope |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2050520A1 true CA2050520A1 (en) | 1993-03-04 |
Family
ID=4148288
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2050520 Abandoned CA2050520A1 (en) | 1991-09-03 | 1991-09-03 | Auxiliary shielding and focussing device for a telescope |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA2050520A1 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2023163617A3 (en) * | 2022-02-23 | 2023-11-02 | Владимир Эльич ПАШКОВСКИЙ | Method and device for supporting the operation of a telescope |
-
1991
- 1991-09-03 CA CA 2050520 patent/CA2050520A1/en not_active Abandoned
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2023163617A3 (en) * | 2022-02-23 | 2023-11-02 | Владимир Эльич ПАШКОВСКИЙ | Method and device for supporting the operation of a telescope |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FZDE | Dead |