Method of measuring magnification of self-assembled telescope by graticule method

Abstract

The present invention discloses a device and method for measuring the magnification of a self-assembled telescope by a graticule method, comprising a support rail, a target illumination scale, an objective lens and an eyepiece, wherein the objective lens is located between the target illumination scale and the eyepiece, a graticule is arranged between the eyepiece and the objective lens, the height of the graticule, the height of the objective lens and the height of the eyepiece match, the target illumination scale is slidably connected to the support rail through a No. 1 standard slide, the objective lens is slidably connected to the support rail through a No. 2 standard slide, the graticule is slidably connected to the support rail through a No. 3 standard slide, and the eyepiece is slidably connected to the support rail through a No. 4 standard slide. The present invention utilizes the lens imaging principle to accurately calculate the focal length of the objective lens and the eyepiece, and starts from the actual magnification of the limited hyperopia of the system, and finally obtains the magnification of the telescope system without focal length, and has a simple structure and is easy to operate; and it more clearly shows students the difference in magnification of a telescope system when observing a near object and a distant object.

Description

Technical Field

[0001] The invention relates to an experimental tool and method, in particular to a method for measuring the magnification of a self-assembled telescope using a graticule method. Background Art

[0002] The magnification measurement of the self-assembled telescope is generally a Kepler telescope structure. The Kepler telescope is composed of two convex lenses. Since the image between the two is a real image, the graticule can be easily installed, and the performance is excellent, so the current military, small astronomy and other professional telescopes use Kepler telescopes.

[0003] From the structural diagram of the Kepler telescope, we can see that the objective lens and the eyepiece form an afocal system, that is, the image focus of the objective lens coincides with the object focus of the eyepiece. The light emitted by an infinitely distant object passes through the objective lens and forms a real image on the focal plane of the objective lens. This real image is then imaged at infinity using the eyepiece (short focal length), which increases the viewing angle and facilitates human eye observation. Figure 4 As shown,

[0004] Telescope magnification It is defined as the angle of the image formed by the visual optical instrument to the human eye (denoted as ) and the angle of the object directly to the human eye (denoted as ), that is,

[0005] (1)

[0006] right Figure 3 In the telescope shown, since the object is at infinity, the angle between the object and the human eye is equal to the angle between the object and the telescope objective lens. According to the geometric optical path,

[0007]

[0008]

[0009] Therefore, the apparent magnification of the telescope is

[0010] (2)

[0011] In the formula , They are L e The object focal length and image focal length of If the focal lengths of the objective lens and the eyepiece are known, the apparent magnification of the telescope can be calculated. The longer the focal length of the objective lens and the shorter the focal length of the eyepiece, the greater the magnification of the telescope.

[0012] In fact, in order to observe objects at different distances, the distance between the objective lens and the eyepiece can be adjusted, and the image focus of the objective lens and the object focus of the eyepiece will not coincide. At this time, the actual magnification of the telescope system is completely different from that of the afocal system.

[0013] At present, the traditional measurement methods for the magnification of the Kepler telescope and the magnification of the focal-free system include direct comparison of viewing angles, imaging formula method, comparison plate method, etc.

[0014] The above methods have low experimental measurement accuracy, and each method has its own shortcomings:

[0015] 1. Direct comparison of viewing angle: It requires that the distance between the measured scale and the objective lens is much greater than the focal length. At the same time, when the viewing angle is directly compared, the operation is difficult and not conducive to students' mastery;

[0016] 2. Imaging formula method: It requires the use of a reading microscope or other auxiliary measurement tools, the system error is large, and the experimental process is cumbersome;

[0017] 3. Comparison plate method: The operation is relatively simple, but the aperture of each lens of the system has great restrictions on the size of the comparison plate. At the same time, in the data processing process, the distance between the objective lens and the eyepiece is ignored, and the experimental data is not accurate enough. Summary of the invention

[0018] In order to solve the defects and shortcomings in the above-mentioned prior art, the present invention provides a device and method for measuring the magnification of a self-assembled telescope using a graticule method, which has a simple structure and is easy to operate; does not require the use of other auxiliary measurement tools; does not need to ignore the interval between the objective lens and the eyepiece, and the experimental data is accurate; the experiment fully utilizes the lens imaging principle, which is conducive to students' further understanding of the structure of the telescope; the experiment uses the method of actual magnification of finite distance to measure the magnification of the afocal system, and more clearly shows students the difference in magnification of a telescope system observing a near object and a distant object.

[0019] The technical solution of the present invention is as follows: a device for measuring the magnification of a self-assembled telescope by a graticule method, comprising a supporting rail, a target illumination scale mounted on the supporting rail, an objective lens and an eyepiece, wherein the objective lens is located between the target illumination scale and the eyepiece, a graticule is arranged between the eyepiece and the objective lens, the height of the graticule, the height of the objective lens and the height of the eyepiece match, the target illumination scale is slidably connected to the supporting rail via a No. 1 standard slide, the objective lens is slidably connected to the supporting rail via a No. 2 standard slide, the graticule is slidably connected to the supporting rail via a No. 3 standard slide, and the eyepiece is slidably connected to the supporting rail via a No. 4 standard slide; the target illumination scale is lifted and connected to the No. 1 standard slide via a scale lifting frame, the objective lens is lifted and connected to the No. 2 standard slide via an objective lens lifting frame, the graticule is lifted and connected to the No. 3 standard slide via a graticule lifting frame, and the eyepiece is lifted and connected to the No. 4 standard slide via an eyepiece lifting frame.

[0020] The invention can avoid the disadvantages of the comparison plate method experimental method, utilize the lens imaging principle, accurately calculate the focal lengths of the objective lens and the eyepiece, start from the limited far-sighted actual magnification of the system, and finally obtain the magnification of the afocal telescope system, with simple structure and convenient operation; no other auxiliary measuring tools are needed; the interval between the objective lens and the eyepiece does not need to be ignored, and the experimental data is accurate; the experiment fully utilizes the lens imaging principle, which is conducive to students' further understanding of the structure of the telescope; the experiment uses the limited far-sighted actual magnification method to measure the magnification of the afocal system, and more clearly shows students the difference in magnification of the telescope system when observing nearby objects and distant objects.

[0021] Preferably, the scale lifting frame includes a No. 1 lifting base, a No. 1 lifting rod liftingly connected to the No. 1 lifting base, and a No. 1 locking bolt locking the No. 1 lifting rod to the No. 1 lifting base, and the target lighting scale is connected to the top of the No. 1 lifting rod through a scale connecting plate.

[0022] This structure ensures that the lifting and lowering of the target lighting scale is stable and reliable.

[0023] Preferably, the objective lens lifting frame includes a No. 2 lifting base, a No. 2 lifting rod lifted and connected to the No. 2 lifting base, and a No. 2 locking bolt for locking the No. 2 lifting rod to the No. 2 lifting base, and the objective lens is connected to the top of the No. 2 lifting rod through an objective lens connecting frame.

[0024] This structure ensures that the lifting and lowering of the objective lens is stable and reliable.

[0025] Preferably, the objective lens connecting frame is provided with an objective lens locking bolt for locking the objective lens on the objective lens connecting frame, and the No. 2 standard slide is provided with a No. 2 slide locking bolt for locking the No. 2 standard slide on the supporting guide rail.

[0026] This structure ensures that the objective lens is installed firmly and reliably.

[0027] Preferably, the reticle lifting frame includes a No. 3 lifting base, a No. 3 main lifting rod and a No. 3 auxiliary lifting rod which are lifted and connected to the No. 3 lifting base, and a No. 3 main locking bolt for locking the No. 3 main lifting rod to the No. 3 lifting base, the No. 3 auxiliary lifting rod is connected to the top of the No. 3 main lifting rod through a transfer rod, the transfer rod is provided with a No. 3 auxiliary locking bolt for locking the No. 3 auxiliary lifting rod to the transfer rod, and the reticle is connected to the top of the No. 3 auxiliary lifting rod through a reticle connecting frame.

[0028] This structure ensures that the lifting and lowering of the reticle is stable and reliable.

[0029] Preferably, the reticle connecting frame is provided with a reticle locking bolt for locking the reticle to the reticle connecting frame, and the No. 3 standard slide is provided with a No. 3 slide locking bolt for locking the No. 3 standard slide to the supporting guide rail.

[0030] This structure ensures that the reticle is installed firmly and reliably.

[0031] Preferably, the eyepiece lifting frame includes a No. 4 lifting base, a No. 4 lifting rod lifted and connected to the No. 4 lifting base, and a No. 4 locking bolt locking the No. 4 lifting rod to the No. 4 lifting base, and the eyepiece is connected to the top of the No. 4 lifting rod through an eyepiece connecting frame.

[0032] This structure ensures that the lifting and lowering of the eyepiece is stable and reliable.

[0033] Preferably, the eyepiece frame is provided with an eyepiece locking bolt for locking the eyepiece to the eyepiece frame, and the No. 4 standard slide is provided with a No. 4 slide locking bolt for locking the No. 4 standard slide to the supporting guide rail.

[0034] This structure ensures that the eyepiece is installed firmly and reliably.

[0035] Preferably, the No. 1 standard slide is provided with a No. 1 slide locking bolt for locking the No. 1 standard slide on the supporting guide rail, a single-headed supporting foot is provided at the bottom of one end of the supporting guide rail, and a double-headed supporting foot is provided at the bottom of the other end of the supporting guide rail, the position of the single-headed supporting foot corresponds to the position of the eyepiece, and the position of the double-headed supporting foot corresponds to the position of the target lighting scale.

[0036] This structure ensures that the support of the support rail is stable and reliable.

[0037] A method for measuring the magnification of a self-assembled telescope using a graticule method, the steps are as follows:

[0038] 1. The steps are as follows:

[0039] 1) Place the instrument on the support rail, the objective lens and the eyepiece form a Kepler telescope system, and focus on the target illumination scale that is perpendicular to the light path in the distance, and then place the graticule between the objective lens and the eyepiece; adjust the position of the graticule so that the scales of the target illumination scale and the graticule image seen in the eyepiece are clear and have no parallax;

[0040] 2) Record the lengths of the scale plate and the illumination scale image, and use y and y' to represent the corresponding values. This means that the object with a length of y will have an image length of y' after being imaged by the objective lens. At the same time, the object distance , and image distance Etc. can be read directly from the guide rail;

[0041] 3) According to the definition of telescope magnification:

[0042]

[0043] Actual magnification:

[0044]

[0045] where y, y′, , , All are measured data, so the actual magnification can be calculated ;

[0046] 4) According to the lens imaging principle and Figure 2 The geometric relations in are:

[0047]

[0048]

[0049] Thus we can obtain: ;

[0050] 4) According to the geometric relationship:

[0051]

[0052]

[0053] Solving the equations, we get: ;

[0054] 6) Due to = , so the magnification of the afocal telescope system is:

[0055] ;

[0056] 7) Calculate the theoretical value through the actual focal length of the lens and perform error analysis.

[0057] The invention can avoid the disadvantages of the comparison plate method experimental method, utilize the lens imaging principle, accurately calculate the focal lengths of the objective lens and the eyepiece, start from the limited far-sighted actual magnification of the system, and finally obtain the magnification of the afocal telescope system, with simple structure and convenient operation; no other auxiliary measuring tools are needed; the interval between the objective lens and the eyepiece does not need to be ignored, and the experimental data is accurate; the experiment fully utilizes the lens imaging principle, which is conducive to students' further understanding of the structure of the telescope; the experiment uses the limited far-sighted actual magnification method to measure the magnification of the afocal system, and more clearly shows students the difference in magnification of the telescope system when observing nearby objects and distant objects. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Figure 1 A schematic diagram of the structure of the device of the present invention from one angle;

[0059] Figure 2 A schematic structural diagram of the device of the present invention from another angle;

[0060] Figure 3 It is the experimental principle diagram of the present invention;

[0061] Figure 4 It is a schematic diagram of an afocal telescope system in the background technology of the present invention;

[0062] In the figure, 1. Support rail, 2. Target illumination scale, 3. No. 1 standard slide, 4. No. 1 slide locking bolt, 5. No. 1 lifting base, 6. No. 1 lifting rod, 7. Scale connecting plate, 8. No. 1 locking bolt, 9. Objective lens, 10. No. 2 standard slide, 11. No. 2 slide locking bolt, 12. No. 2 lifting base, 13. No. 2 lifting rod, 14. Objective lens connecting frame, 15. No. 2 locking bolt, 16. Objective lens locking bolt, 17. Graticule, 18. No. 3 standard slide, 19. No. 3 slide locking bolt Bolt, 20. No. 3 lifting base, 21. No. 3 main lifting rod, 22. No. 3 auxiliary lifting rod, 23. Adapter rod, 24. Reticle frame, 25. No. 3 main locking bolt, 26. No. 3 auxiliary locking bolt, 27. Reticle locking bolt, 28. Eyepiece, 29. No. 4 standard slide, 30. No. 4 slide locking bolt, 31. No. 4 lifting base, 32. No. 4 lifting rod, 33. Eyepiece frame, 34. No. 4 locking bolt, 35. Eyepiece locking bolt, 36. Single-head support foot, 37. Double-head support foot. DETAILED DESCRIPTION

[0063] The present invention will be further described in detail below in conjunction with the accompanying drawings, but this does not limit the protection scope of the present invention.

[0064] like Figure 1and 2As shown, a device for measuring the magnification of a self-assembled telescope by a graticule method comprises a support rail 1, a target illumination scale 2 mounted on the support rail 1, an objective lens 9 and an eyepiece 28, the objective lens 9 is located between the target illumination scale 2 and the eyepiece 28, a graticule 17 is arranged between the eyepiece 28 and the objective lens 9, the height of the graticule 17, the height of the objective lens 9 and the height of the eyepiece 28 match, the target illumination scale 2 is slidably connected to the support rail 1 through a first standard slide 3, and the objective lens 9 is slidably connected to the support rail 1 through a second standard slide 10 On the support rail 1, the graticule 17 is slidably connected to the support rail 1 through the No. 3 standard slide 18, and the eyepiece 28 is slidably connected to the support rail 1 through the No. 4 standard slide 29; the target illumination scale 2 is lifted and connected to the No. 1 standard slide 3 through the scale lifting frame, the objective lens 9 is lifted and connected to the No. 2 standard slide 10 through the objective lens lifting frame, the graticule 17 is lifted and connected to the No. 3 standard slide 18 through the graticule lifting frame, and the eyepiece 28 is lifted and connected to the No. 4 standard slide 29 through the eyepiece lifting frame. The scale lifting frame includes a No. 1 lifting base 5, a No. 1 lifting rod 6 lifted and connected to the No. 1 lifting base 5, and a No. 1 locking bolt 8 for locking the No. 1 lifting rod 6 to the No. 1 lifting base 5, and the target illumination scale 2 is connected to the top of the No. 1 lifting rod 6 through a scale connecting plate 7. The objective lens lifting frame includes a No. 2 lifting base 12, a No. 2 lifting rod 13 liftingly connected to the No. 2 lifting base 12, and a No. 2 locking bolt 15 for locking the No. 2 lifting rod 13 to the No. 2 lifting base 12. The objective lens 9 is connected to the top of the No. 2 lifting rod 13 through an objective lens connecting frame 14. The objective lens connecting frame 14 is provided with an objective lens locking bolt 16 for locking the objective lens 9 to the objective lens connecting frame 14, and the No. 2 standard slide 10 is provided with a No. 2 slide locking bolt 11 for locking the No. 2 standard slide 10 to the support rail 1. The reticle lifting frame includes a No. 3 lifting base 20, a No. 3 main lifting rod 21 and a No. 3 auxiliary lifting rod 22 liftingly connected to the No. 3 lifting base 20, and a No. 3 main locking bolt 25 for locking the No. 3 main lifting rod 21 to the No. 3 lifting base 20, the No. 3 auxiliary lifting rod 22 is connected to the top of the No. 3 main lifting rod 21 through a transfer rod 23, and the transfer rod 23 is provided with a No. 3 auxiliary locking bolt 26 for locking the No. 3 auxiliary lifting rod 22 to the transfer rod 23, and the reticle 17 is connected to the top of the No. 3 auxiliary lifting rod 22 through a reticle connecting frame 24. The reticle connecting frame 24 is provided with a reticle locking bolt 27 for locking the reticle 17 to the reticle connecting frame 24, and the No. 3 standard slide 18 is provided with a No. 3 slide locking bolt 19 for locking the No. 3 standard slide 18 to the support guide rail 1. The eyepiece lifting frame includes a No. 4 lifting base 31, a No. 4 lifting rod 32 liftingly connected to the No. 4 lifting base 31, and a No. 4 locking bolt 34 for locking the No. 4 lifting rod 32 to the No. 4 lifting base 31. The eyepiece 28 is connected to the top of the No. 4 lifting rod 32 through an eyepiece connecting frame 33.The eyepiece connecting frame 33 is provided with an eyepiece locking bolt 35 for locking the eyepiece 28 on the eyepiece connecting frame 33, and the No. 4 standard slide 29 is provided with a No. 4 slide locking bolt 30 for locking the No. 4 standard slide 29 on the support rail 1. The No. 1 standard slide 3 is provided with a No. 1 slide locking bolt 4 for locking the No. 1 standard slide 3 on the support rail 1, a single-head support foot 36 is provided at the bottom of one end of the support rail 1, and a double-head support foot 37 is provided at the bottom of the other end of the support rail 1, the position of the single-head support foot 36 corresponds to the position of the eyepiece 28, and the position of the double-head support foot 37 corresponds to the position of the target lighting scale 2.

[0065] like Figure 3 As shown, a test method for a device for measuring the magnification of a self-assembled telescope using a graticule method, the steps are as follows:

[0066] 1) Place the instrument on the support rail, the objective lens and the eyepiece form a Kepler telescope system, and focus on the target illumination scale that is perpendicular to the light path in the distance, and then place the graticule between the objective lens and the eyepiece; adjust the position of the graticule so that the scales of the target illumination scale and the graticule image seen in the eyepiece are clear and have no parallax;

[0067] 2) Record the lengths of the scale plate and the illuminated ruler image, and use y and y' to represent the corresponding values. This means that the object with a length of y (corresponding to the scale of the ruler) will have an image length of y' after being imaged by the objective lens. At the same time, the object distance , and image distance Etc. can be read directly from the guide rail;

[0068] 3) According to the definition of telescope magnification:

[0069]

[0070] Actual magnification:

[0071]

[0072] where y, y′, , , All are measured data, so the actual magnification can be calculated ;

[0073] 4) According to the lens imaging principle and Figure 2 The geometric relations in are:

[0074]

[0075]

[0076] Thus we can obtain: ;

[0077] 5) According to the geometric relationship:

[0078]

[0079]

[0080] Solving the equations, we get: ;

[0081] 6) Due to = , so the magnification of the afocal telescope system is:

[0082] ;

[0083] 7) Calculate the theoretical value through the actual focal length of the lens and perform error analysis.

Claims

1. A method for measuring the magnification of a self-assembled telescope using a graticule method, implemented by a device for measuring the magnification of a self-assembled telescope using a graticule method, characterized in that: The device comprises a supporting rail, a target illumination scale mounted on the supporting rail, an objective lens and an eyepiece, wherein the objective lens is located between the target illumination scale and the eyepiece, a graticule is arranged between the eyepiece and the objective lens, the height of the graticule, the height of the objective lens and the height of the eyepiece match, the target illumination scale is slidably connected to the supporting rail via a No. 1 standard slide, the objective lens is slidably connected to the supporting rail via a No. 2 standard slide, the graticule is slidably connected to the supporting rail via a No. 3 standard slide, and the eyepiece is slidably connected to the supporting rail via a No. 4 standard slide; the target illumination scale is lifted and connected to the No. 1 standard slide via a scale lifting frame, the objective lens is lifted and connected to the No. 2 standard slide via an objective lens lifting frame, the graticule is lifted and connected to the No. 3 standard slide via a graticule lifting frame, and the eyepiece is lifted and connected to the No. 4 standard slide via an eyepiece lifting frame; The method is used to obtain the actual magnification of the telescope and the magnification of the afocal telescope system respectively through the following steps; The test steps are as follows: 1) Place the instrument on the support rail, the objective lens and the eyepiece form a Kepler telescope system, and focus on the target illumination scale that is perpendicular to the light path in the distance, and then place the graticule between the objective lens and the eyepiece; adjust the position of the graticule so that the scales of the target illumination scale and the graticule image seen in the eyepiece are clear and have no parallax; 2) Record the lengths corresponding to the scale of the graticule and the image of the illuminated ruler, and use y and y′ to represent the corresponding values. This means that for an object with a length of y, the image length obtained after the objective lens forms an image is y′. At the same time, the object distances u1, u2 and the image distance v1 can be directly read from the guide rail; 3) According to the definition of telescope magnification: Actual magnification: where y, y′, , , All are measured data, find the actual magnification ; 4) According to the principle of lens imaging, the geometric relationship is: Thus we can obtain: ; 5) According to the geometric relationship: Solving the equations, we get: ; 6) Due to = , so the magnification of the afocal telescope system is: 。 2. The method according to claim 1, Features: The scale lifting frame includes a No. 1 lifting base, a No. 1 lifting rod liftingly connected to the No. 1 lifting base, and a No. 1 locking bolt locking the No. 1 lifting rod to the No. 1 lifting base. The target lighting scale is connected to the top of the No. 1 lifting rod through a scale connecting plate.

3. The method according to claim 1, characterized in that: The objective lens lifting frame comprises a No. 2 lifting base, a No. 2 lifting rod liftingly connected to the No. 2 lifting base, and a No. 2 locking bolt locking the No. 2 lifting rod to the No. 2 lifting base. The objective lens is connected to the top of the No. 2 lifting rod through an objective lens connecting frame.

4. The method according to claim 3, characterized in that: The objective lens connecting frame is provided with an objective lens locking bolt for locking the objective lens on the objective lens connecting frame, and the No. 2 standard slide is provided with a No. 2 slide locking bolt for locking the No. 2 standard slide on the supporting guide rail.

5. The method according to claim 1, characterized in that: The reticle lifting frame includes a No. 3 lifting base, a No. 3 main lifting rod and a No. 3 auxiliary lifting rod which are lifted and connected to the No. 3 lifting base, and a No. 3 main locking bolt which locks the No. 3 main lifting rod to the No. 3 lifting base, the No. 3 auxiliary lifting rod is connected to the top of the No. 3 main lifting rod through a transfer rod, the transfer rod is provided with a No. 3 auxiliary locking bolt which locks the No. 3 auxiliary lifting rod to the transfer rod, and the reticle is connected to the top of the No. 3 auxiliary lifting rod through a reticle connecting frame.

6. The method according to claim 5, characterized in that: The reticle connecting frame is provided with a reticle locking bolt for locking the reticle on the reticle connecting frame, and the No. 3 standard slide is provided with a No. 3 slide locking bolt for locking the No. 3 standard slide on the supporting guide rail.

7. The method according to claim 1, characterized in that: The eyepiece lifting frame includes a No. 4 lifting base, a No. 4 lifting rod liftingly connected to the No. 4 lifting base, and a No. 4 locking bolt locking the No. 4 lifting rod to the No. 4 lifting base. The eyepiece is connected to the top of the No. 4 lifting rod through an eyepiece connecting frame.

8. The method according to claim 7, characterized in that: The eyepiece connecting frame is provided with an eyepiece locking bolt for locking the eyepiece on the eyepiece connecting frame, and the No. 4 standard slide is provided with a No. 4 slide locking bolt for locking the No. 4 standard slide on the supporting guide rail.

9. The method according to claim 1, characterized in that: The No. 1 standard slide is provided with a No. 1 slide locking bolt for locking the No. 1 standard slide on the supporting guide rail, a single-head supporting foot is provided at the bottom of one end of the supporting guide rail, and a double-head supporting foot is provided at the bottom of the other end of the supporting guide rail, the position of the single-head supporting foot corresponds to the position of the eyepiece, and the position of the double-head supporting foot corresponds to the position of the target lighting scale.

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