The invention aims for a telescope provided with a device for adjusting the tilt and the position of a mirror.
The invention relates to the technical field of adjustment devices for optical systems of telescopes.
A telescope is intended to observe objects in the sky. It allows, among other things, to observe planets, stars, comets, nebulae, galaxies, and in general, celestial objects, near or far. The telescope is used in particular by astronomers, although its use has been democratized in recent years and stargazing has become a passion for many people of different generations. In order to meet the demands of the growing number of consumers, manufacturers have had to diversify these instruments to meet the demands of a wider audience.
Currently known telescopes on the market integrate an optical system formed by an arrangement of mirrors and/or lenses arranged inside a hollow body so as to collect the light rays emitted by the observed object and form an image of said object in a focal plane.
To obtain a quality image, the sensor 3 must be positioned in the focal plane F and the axis X-X of the mirror 2 must be collinear with the optical axis A-A. The position of the mirror 2 on the optical axis A-A (i.e. the distance between the mirror and the sensor 3) and its tilt may be out of adjustment during handling of the telescope and/or may be incorrectly set due to manufacturing constraints and tolerances. A maladjusted mirror is illustrated by the dotted lines in
Also, it is common for telescopes to incorporate a device for adjusting the tilt (angular adjustment) and position (focus) of at least the primary mirror. However, the current adjustment devices are complex to make, expensive, and difficult for an amateur user to adjust. Furthermore, they generally require the dismantling of certain parts of the telescope to access the adjustment device, which makes their use even more complex.
The invention aims to overcome this state of affairs. In particular, one aim of the invention is to propose a mirror tilt and position adjustment device that is simple to make and inexpensive while being accurate and easy to adjust for an amateur user.
The solution proposed by the invention is a telescope comprising:
This telescope is remarkable in that the adjustment device comprises:
The user can very easily make a very precise focus by simply turning the button. By operating in this way, the mobile carriage translates along the optical axis driving the support plate and the mirror. Tilt adjustment can also be done very simply and precisely by actuating the actuator. All these adjustments are made from the outside of the hollow body without having to disassemble any part of the telescope, and are located on the housing part, which greatly simplifies their implementation. The design of this adjustment device is also particularly simple, allowing to limit the costs.
Other advantageous characteristics of the invention are listed below. Each of these characteristics may be considered alone or in combination with the outstanding characteristics defined above. Where applicable, each of these characteristics contributes to the resolution of specific technical problems defined further in the description, to which the outstanding characteristics defined above do not necessarily contribute. Where applicable, these may be the subject of one or more divisional patent applications:
Other advantages and characteristics of the invention will become clearer upon reading the description of the following preferred embodiment, by reference to the appended drawings, provided for guidance as non-limiting examples, wherein:
Such as used here, unless otherwise specified, the use of ordinal adjectives “first”, “second”, etc., to describe an object simply indicates that different occurrences of similar objects are mentioned and does not imply that the objects thus described must be in any given sequence, whether in time, space, classification, or any other way.
The telescope which is the subject matter of the invention is used for the observation of celestial objects (planets, stars, constellations, nebulae, galaxies, deep sky objects, etc.) but can also be used for the observation of non-celestial objects such as landscapes, characters, animals, etc.
The telescope can be of the type described in
The hollow body 1 preferably has the shape of a hollow tube with a circular cross-section, but could be a tube with an oval, square, octagonal or other cross-section. It is specified that the hollow body 1 is not necessarily tubular in shape, but can be conical, or formed of portions of tubes or of cones, for example. The hollow body 1 can be made of metal, plastic, composite material, etc. For example, its length is between 200 mm and 1,000 mm, its diameter between 50 mm and 500 mm and its thickness between 1 mm and 10 mm.
The mirror 2 is preferably a concave parabolic mirror, of which the diameter corresponds substantially to that of the hollow body 1. In
The sensor 3 is arranged on the optical axis A-A, in the focal plane F to acquire the image of the observed object O. The sensor 3 is a photosensitive component used to convert the light rays R into electrical signals. The image of the observed object being acquired by the sensor 3, therefore an indirect observation of the object is made, the user not directly observing the image through an eyepiece. The sensor 3 can preferably be a CCD (Charged Coupled Device) or CMOS (Complementary Metal Oxide Semiconductor) sensor with a pixel arrangement (preferably generating color images). This type of sensor 3 has small dimensions, which allows it to be easily installed in the hollow body 1, without interfering with the rays R, while maintaining optimal brightness. The diameter of the sensor 3 is for example between 15 mm and 30 mm.
The electrical signals generated by the sensor 3 can be transmitted to an electronic image processing unit (not shown) by a wired or wireless connection (Bluetooth®, Wifi®, ZigBee®, etc.). The images of the object O are then viewed on a screen, which can be distant from the telescope, for example on the screen of a smartphone.
The device for adjusting the focus and tilt of the mirror 2 will now be described in detail with reference to
The mirror 2 is housed in the support plate 20. The latter has a circular cup shape adjusted to the dimensions of the mirror 2. The front face of the plate 20 has a housing 200 wherein the mirror 2 is installed. The plate 20 is made of injected plastic or metal, for example aluminum. The mirror 2 is held in position in the plate 20 by means of a cover 21 with a central opening leaving the active surface (or reflecting surface) of the mirror 2 free. The latter has a threaded sidewall 210 that screws onto a similarly threaded sidewall 201 of the plate 20. However, the lid 21 can be fixed to the plate 20 in another way, for example by clipping, gluing, welding, etc.
Thus positioned, the mirror 2 is then sandwiched between the front face of the plate 20 and the rear face of the cover 21. The axis of the plate 20 coincides with the axis X-X of the mirror 2. In order to ensure a flexible clamping of the mirror 2 in the plate 20 when the cover is mounted, flexible pads or tabs 202, for example made of rubber or silicone, are advantageously used. These pads or tabs 202 are homogenously installed on the rear face of the mirror 2 and/or in the housing 200 of the plate 20.
The plate 20 is secured to a carriage 4 mounted mobile in translation in the body 1, along the optical axis A-A of the telescope. In
The plate 40 can be made of injected plastic or aluminum, for example. It has a tubular housing 400 that passes right through the plate 40. This housing 400 is preferably cylindrical in shape and sized to receive the axis 41. It is centered on the middle of the plate 40. Its inner wall has one or more longitudinal guide grooves 402, the function of which is described further in the description.
The axis 41 is advantageously in the form of a hollow cylindrical tube provided with a flange 410 at its distal end. This is closed by a bottom wall. The outer diameter of axis 41 is less than the inner diameter of the housing 400 so as to leave an annular space 413 (which can be seen in
An arrangement 401 is made on the front face of the plate 40, around the tubular housing 400. This arrangement 401 is shaped to receive the flange 410 of the axis 41. The flange 410 is fixed in the arrangement 401 (and therefore the axis 41 on the plate 40) by means of screws 411. These screws 411 pass through through holes 412 made in the flange 410 and screw into tapped holes 403 made in the arrangement 401.
The length of the axis 41 is greater than that of the housing 400. In this configuration, and as illustrated in
The nut 42 is housed inside the axis 41. It is held in position in the axis 41 by means of screws 420. The latter pass through through holes 414 made in a bottom wall of the axis 41 and screw into tapped holes 422 made on the nut 42. The outer wall of the nut 42 is advantageously provided with longitudinal grooves 423 engaging with complementary ribs (not shown) made on the inner wall of the axis 41. These grooves and ribs form a locator allowing the tapped holes 422 to be positioned very simply opposite the holes 414.
The nut 42 is preferably made of Teflon or POM (for Poly-Oxy-Methylene) so as to limit friction with the adjusting screw described earlier in the description.
The plate 20 is secured to the carriage 4 by means of a hinge allowing the tilt of said plate to be modified. This hinge is preferably a ball-joint centered on the axis of the plate 20 and, therefore, on the center of the mirror 2 and on the optical axis A-A. The plate 20 thus has three degrees of freedom in rotation. This swivel movement of the plate 20 allows it to be tilted in all directions. The use of a ball-joint 5 centered on the axis of the mirror 2 (and on the optical axis) offers, the main advantage of being able to adjust the angle of the plate 2 (and therefore the angle of the mirror), without modifying its focal length, or at least, by minimizing the tampering of this focal length.
In
At least one actuator is mounted mobile in the carriage 4. This actuator acts on the plate 20, such that a movement of said actuator causes a modification in the tilt of said plate. In
Each adjusting screw 6 is mounted in engagement in a threaded shaft 406 made in the plate 40. The shaft 406 is long enough such that the screw 6 does not rotate in it. For example, the length of the shaft is greater than or equal to half the length of the screw 6. The screw 6 is inserted from the rear face of the plate 40 and comes out at its front face.
Referring to
As the adjusting screw 6 is rotated back and forth in the shaft 406, the distal end 60 of the screw 6 more or less protrudes from the front face of the plate 40 and pushes the plate 20. This thrust force will cause the plate 20 to pivot around the ball-joint 5 such that its tilt angle will change. The adjusting screw 6 is rotated manually, by means of a suitable tool (for example, a screwdriver or an allen key) which engages in a recess made in the head of said screw.
Referring to
The plate 20, supporting the mirror 2, is likely to tilt under its own weight, which would cause an untimely tampering of its tilt. To overcome this, it is possible to provide a ball-joint connection between the distal end 60 of the adjusting screw 6 and the seat 204. This solution can be considered, however it generates mechanical stresses, even minimal, on the adjusting screw 6 and/or on the plate 20, when said screw acts on said plate. Furthermore, since a ball-joint connection is not perfect due to manufacturing tolerances, a certain clearance may exist between the distal end 60 and the seat 204, which clearance limits the precision of the adjustment of the tilt angle of the mirror 2.
To resolve this problem, elastic members 61 act on the plate 20. In
Referring to
Referring to
The carriage 4 is driven in translation by means of a screw/nut mechanism that can be actuated by means of an adjustment button. The nut for this mechanism is the nut 42 described above. The adjusting screw of the screw/nut mechanism, the adjustment button and the housing part with which they are associated will now be described with reference to
The adjusting screw 70 of the screw/nut mechanism engages with the nut 42 mounted in the carriage 4. The screw 70 and the nut 42 are sized such that the stroke of the carriage 4 is limited, for example less than or equal to 5 cm. The screw head 70 has a flange 701 comprising holes 702 for screw passage.
The adjustment button 71 is presented in the form of a circular part in
The button 71 has a circular opening 710 passing through said button. This opening is coaxial to the axis of the button 71. It is sized to allow the passage of the screw 70. An arrangement 711 is made on the front face of the button 71, around the opening 710. This arrangement 711 is shaped to receive the flange 701 of the screw 70. The flange 701 is fixed in the arrangement 711 (and therefore the screw 70 on the button 71) by means of screws 703, possibly associated with lock washers 7,030. These screws 703 pass through through holes 702 made in the flange 713 and screw into tapped holes 711 made in the arrangement 401.
To improve the appearance and prevent unauthorized access to the screws 703, a cover 74 may cover the front face of the button 71. This cover 74 can, in particular, be glued by an adhesive strip 75.
A bearing 72, advantageously made of steel to limit friction. This bearing 72 is advantageously in the form of a hollow cylindrical tube provided with a flange 720 at its proximal end. The two ends of the bearing 72 are open to allow the adjusting screw 70 to pass through. The outer diameter of the bearing 72 is less than the inner diameter of the annular space 413 which can be seen in
The bearing 72 is fixed to a housing part 8 of the hollow body 1. In particular, the housing part 8 can be fixed to one end of the tube forming the body 1 (
In
The housing part 8 has a tubular housing 810 passing through said part and protruding from the rear face of said part (
The adjustment button 71 is rotatably mounted mobile in the housing part 8, around an axis which is coaxial to the optical axis A-A of the telescope. In
According to one embodiment, the button 71 is held in position on the housing part 8, and more particularly in the housing 812, while retaining its freedom of rotation. This holding in position is achieved by means of a locking part 73. In
The locking part 73 has a circular opening 730 passing through said part. This opening is coaxial to the axis of the part 73. It is sized to allow the passage of the bearing 72. However, the diameter of the opening 730 is less than the diameter of the flange 720 such that the latter acts as a stop.
The mounting of the button 71 on the bearing 72 is preferably done in the following way:
In this configuration, and as shown in
When the button 71 and bearing 72 are installed on the housing part 8, this assembly is assembled to the assembly formed by the mirror 2, the plate 20 and the carriage 40. Referring to
During assembly, the bearing 72 overlaps the axis 41 and is housed in the annular space 413. Referring to
In this assembly configuration, when a user turns the button 71, the adjusting screw 70 is rotated. The rotational movement of the screw 70 leads to a translational movement of the nut 42 and thus to a translation of the carriage 4 along the optical axis. In the appended Figures, the screw 70 and nut 42 are coaxial with the optical axis A-A. This advantageous embodiment allows for a button 71 that is centered on the housing part 8 and on the optical axis A-A. The compactness of the adjustment device can thus be optimized. This arrangement of the screw 70 and of the nut 42 further allows to limit the forces to move the carriage 4, the plate 20 and the mirror 4. The user does not need to force the button 71 to turn.
In
When the user focuses, they turn the button 71 to move the carriage 4 along the optical axis, until the mirror 2 reaches the desired position. However, it is not desirable that the user can unreasonably tamper with the position of the mirror 2 on the optical axis. Indeed, if the user turns the button 71 ten times, the focal length of the optical system will be highly tampered with. And an amateur user will find it very difficult to find a consistent position of mirror 2 to obtain a quality image. It therefore seems desirable to limit the rotation of the button 71 and the movement of the carriage 4.
To do this, and as illustrated in
By limiting the rotation of the button 71, the articulation of the carriage 4 is limited. It seems advantageous in terms of use and handling by an amateur, to limit the translation of the carriage 4 to a distance of between 1 mm and 2 cm (0.5 mm to 1 cm forwards and 0.5 cm to 1 cm backwards). In practice, the authorized articulation corresponds to the pitch of the adjusting screw 70 (for example, if its pitch is 4 mm, the articulation of the carriage 4 is 4 mm). The user can thus focus very quickly, without the risk of adjusting the focal length of the optical system too much. However, the limited articulation of the carriage 4 allows the user to focus on objects closer than a celestial object, for example a landscape, a monument, etc.
In any case, to allow fine adjustment of the position of the mirror 2, the button 71 and/or the housing part 8 are preferably provided with graduations 716, 816. These graduations can be seen by the user.
An adjustment of the tilt and of the position of the mirror 2 is advantageously performed in the factory to obtain the best possible image quality. Such an adjustment can be done by means of a Bahtinov mask and/or from a laser source. For an amateur user, the adjustment can be done in several known ways. For example, the focus is made according to the sharpness of the image. And adjustment of the mirror tilt can be done by aiming at a star and minimizing the size of its image: if the adjustment is correct, the image of the star is a point; if the adjustment is wrong, the image of the star is bigger.
The factory adjustment can consist of presetting the position of the carriage 4 with the adjusting screw 70. The operator has access to the entire stroke of the screw-nut mechanism such that they can easily overcome the variations in the dimensions of the various parts, and make an optimal adjustment where the distance between the mirror 2 and the sensor 3 is equal to the focal length of the optical system. Once this adjustment is done, the operator fixes the button 71 to the adjusting screw 70. The button 71 is positioned on a “zero” scale (materialized by a lug 717 of the button 71 positioned vertically). The operator can then prevent access to the factory adjustment by placing down the cover 74. It must be noted that the user can easily find this factory adjustment by repositioning the button 71 on the “zero” graduation.
As illustrated in
The arrangement of the different elements and/or means and/or steps of the invention, in the embodiments described above, must not be understood as requiring such an arrangement in all the implementations. Other variants can be provided, and in particular:
Furthermore, one or more characteristics outlined only in one embodiment can be combined with one or more other characteristics outlined only in another embodiment. Likewise, one or more characteristics outlined only in one embodiment can be generalized to the other embodiments, even if this or these characteristic(s) is/are described only in combination with other characteristics.
Number | Date | Country | Kind |
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1910648 | Sep 2019 | FR | national |
Filing Document | Filing Date | Country | Kind |
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PCT/FR2020/051675 | 9/25/2020 | WO |
Publishing Document | Publishing Date | Country | Kind |
---|---|---|---|
WO2021/058921 | 4/1/2021 | WO | A |
Number | Name | Date | Kind |
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6118579 | Endemann | Sep 2000 | A |
Number | Date | Country |
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2923302 | May 2009 | FR |
S61160711 | Jul 1986 | JP |
Entry |
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International Search Report issued on Dec. 18, 2020 in corresponding International application No. PCT/FR2020/051675; 5 pages. |
Number | Date | Country | |
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20220326477 A1 | Oct 2022 | US |