CN115857136A - Digital auto-collimation theodolite optical system with automatic focusing function - Google Patents

Abstract

The application discloses a digital autocollimation theodolite optical system with automatic focusing function. Including: automatic focusing device, the automatic focusing device includes: objective lens assembly, the objective lens assembly includes: main tube; the main tube has a first section and a second section, the first section is provided with an objective lens group; the second section is close to the first section The outer wall is provided with a driving part; the focusing assembly includes: a focusing lens barrel; the focusing lens barrel is sleeved on the second section; a focusing lens group is arranged inside the focusing lens barrel; There is a threaded seat; the driving shaft of the driving part is threadedly connected with the threaded seat through the threaded shaft; when the driving part moves, the threaded shaft is driven to rotate, and the relative position between the threaded shaft and the threaded seat is adjusted to make the distance between the main tube and the focusing lens tube The relative position between them is changed to adjust the focal length between the objective lens group and the focusing lens group. Compared with the traditional manual operation, this system precisely adjusts the focal length between the objective lens group and the focusing lens group, which not only improves the detection efficiency and accuracy, but also improves the automation level.

Description

A digital autocollimation theodolite optical system with automatic focusing function

Technical Field

The present disclosure generally relates to the technical field of system assembly precision measurement, and in particular to a digital autocollimation theodolite optical system with an automatic focusing function.

Background Art

With the vigorous development of my country's aerospace industry, the installation and adjustment of aerospace payload systems usually rely on collimation measurement systems. However, the installation and adjustment of aerospace payload systems is arduous and complex, requiring the measurement equipment to have higher precision, more portable, and more integrated functions. The traditional electronic theodolites, autocollimators and other instruments used can no longer meet the requirements of completing complex inspection tasks such as angle, attitude parameter measurement and coordinate measurement with high efficiency and quality.

However, most of the photoelectric autocollimation theodolites and target aiming processes currently used must rely on manual operation, which is prone to errors, resulting in low detection efficiency and low accuracy. Therefore, we propose a digital autocollimation theodolite optical system with automatic focusing function to solve the above problems.

Summary of the invention

In view of the above-mentioned defects or deficiencies in the prior art, it is desired to provide a digital autocollimation theodolite optical system with an automatic focusing function, which improves the automation level and enhances the detection efficiency and accuracy.

The present application provides a digital autocollimation theodolite optical system with an automatic focusing function.

The optical system can realize a photoelectric self-collimation function with higher precision through automatic focusing, and can realize automatic measurement and data analysis of misalignment angles. At the same time, it can also automatically focus to a measuring point mode and realize automatic focusing alignment according to different distance values;

The optical system achieves a substantial increase in the focal length of the autocollimation optical path while keeping the total length of the lens barrel unchanged, thereby achieving high-precision autocollimation angle measurement. At the same time, the automatic acquisition of CCD images effectively avoids measurement errors caused by eye fatigue and different parallaxes of the human eye during the optical autocollimation process. The system is equipped with measurement and data analysis software, which can quickly provide analysis results.

The optical system comprises:

An automatic focusing device, the automatic focusing device comprising:

The objective lens assembly comprises: a main barrel; the main barrel has a first section and a second section, the first section is provided with an objective lens group; the second section is provided with a driving member on an outer wall close to the first section;

A focusing assembly, the focusing assembly comprising: a focusing lens barrel; the focusing lens barrel is sleeved on the second section; a focusing lens group is arranged inside the focusing lens barrel; and a threaded seat is arranged on the outer wall of the focusing lens barrel;

The driving shaft of the driving member is threadedly connected to the threaded seat through a threaded shaft; when the driving member is in motion, the threaded shaft is driven to rotate, and the relative position between the threaded shaft and the threaded seat is adjusted, so that the relative position between the main barrel and the focusing lens barrel is changed, so as to adjust the focal length between the objective lens group and the focusing lens group;

A visual optical self-collimation component, the visual optical self-collimation component comprising: a first LED light source, a first frosted glass, a first graticule, a first right-angle prism, a first beam splitter prism, a second beam splitter prism, an objective lens group, a self-collimation reflector, a focusing lens group, an image transfer prism, a second graticule and an eyepiece group; a second frosted glass and a second LED light source are sequentially arranged below the first graticule;

A control unit is electrically connected to the driving member. The control unit sends a control instruction to the driving member. The driving member receives the control instruction and rotates according to the control instruction, so that the threaded shaft can be extended and retracted in the threaded seat. When the focal length between the objective lens group and the focusing lens group reaches a preset focal length value, the driving member stops moving, and the driving shaft of the driving member locks the relative position of the threaded shaft and the threaded seat. The corresponding relationship between the moving position and the focal length is determined by prior calibration, and the start and stop of the driving member are controlled by the control unit according to the ranging value for adjustment, so as to further improve the degree of automation of focusing.

According to the technical solution provided in the embodiment of the present application, the driving component is an electric drive motor.

According to the technical solution provided in the embodiment of the present application, the objective lens group includes: a first telephoto objective lens and a second telephoto objective lens, and the first telephoto objective lens is arranged away from the focusing lens barrel relative to the second telephoto objective lens.

According to the technical solution provided in the embodiment of the present application, the objective lens assembly further includes:

An objective lens seat is arranged at a position of the first section close to the free end thereof; the objective lens seat is provided with a mounting channel for mounting a first telephoto objective lens and a second telephoto objective lens;

An objective lens frame is arranged at the free end of the first section, and an installation space is formed between the objective lens frame and the first section for installing an objective lens seat;

An objective lens spacer, arranged at a gap between the first telephoto objective lens and the second telephoto objective lens;

An objective lens cover, which is arranged outside the objective lens frame;

An aperture is arranged inside the first section, and the aperture is located between the objective lens group and the focusing lens group.

According to the technical solution provided in the embodiment of the present application, the focusing lens group includes:

A first focusing lens and a second focusing lens, wherein the first focusing lens is arranged relative to the second focusing lens and close to the second telephoto objective lens.

According to the technical solution provided in the embodiment of the present application, the focusing component also includes:

A focusing lens seat is located in the focusing lens barrel and connected to the inner wall of the focusing lens barrel; a mounting surface is formed on a side of the focusing lens seat close to the second telephoto objective lens for mounting the second focusing lens;

A focusing lens tube, which is arranged on the focusing lens seat and is close to the second telephoto objective lens, and the first focusing lens is installed inside the focusing lens tube;

The spring sheet is arranged between the first focusing lens and the second focusing lens.

The technical solution provided in the embodiment of the present application also includes:

A focus-adjustable zoom system, comprising: an objective lens group, a focusing lens group, an image transfer prism and an eyepiece group;

An autocollimation optical system, the autocollimation optical system comprising: a visual optical autocollimation component and a photoelectric autocollimation component;

The visual optical autocollimation assembly comprises: a first LED light source, a first frosted glass, a first graticule, a first right-angle prism, a first beam splitter, a second beam splitter, an objective lens group, an autocollimation reflector, a focusing lens group, an image transfer prism, a second graticule and an eyepiece group; a second frosted glass and a second LED light source are sequentially arranged below the first graticule;

The photoelectric autocollimation assembly includes: a first LED light source, a first frosted glass, a first graticule, a first right-angle prism, a first beam splitter prism, a second beam splitter prism, an objective lens group, an autocollimation reflector, a second right-angle prism, a first CCD focusing lens, a filter, and a second CCD focusing lens.

According to the technical solution provided in the embodiment of the present application, the first telescopic objective lens is arranged relatively close to the autocollimating reflector.

According to the technical solution provided in the embodiment of the present application, the eyepiece set includes: a first eyepiece, a second eyepiece and a third eyepiece arranged in sequence, wherein the first eyepiece is arranged relatively close to the image relay prism;

The image-transmitting prism is a Porro prism, which is formed by gluing three right-angle prisms together; the first beam splitter prism and the second beam splitter prism are both formed by gluing four right-angle prisms together, and the processing tolerance of a single prism is designed to achieve a mutual fit between the processing difficulty and the design standard, thereby avoiding deflection of the incident light axis and the output light axis.

According to the technical solution provided in the embodiment of the present application, the focusing lens group includes: a first focusing lens and a second focusing lens, and the first focusing lens is arranged relatively close to the second graticule.

In summary, the present application specifically discloses a specific structure of a digital autocollimation theodolite optical system with an automatic focusing function. The present application designs an automatic focusing device, which has an objective lens assembly and a focusing assembly for use together, the objective lens assembly includes a main barrel, which has a first section and a second section, an objective lens group is arranged inside the first section, a driving member is arranged on the outer wall of the second section close to the first section, and a threaded shaft is arranged at the end of the driving shaft of the driving member; the focusing assembly includes a focusing lens barrel sleeved on the second section, a threaded seat is arranged on the outer wall of the focusing lens barrel, and the threaded seat is threadedly connected to the threaded shaft; when the driving member is activated, it can drive the threaded shaft to rotate, so that the relative position between the threaded shaft and the threaded seat changes, thereby changing the relative position between the main barrel and the focusing lens barrel, so as to adjust the focal length between the objective lens group and the focusing lens group.

Compared with traditional manual operation, the optical system of this digital autocollimation theodolite adopts a drive component and a screw transmission method to accurately adjust the focal length between the objective lens group and the focusing lens group, which can improve the detection efficiency and accuracy while also improving the automation level of the system.

BRIEF DESCRIPTION OF THE DRAWINGS

Other features, objects and advantages of the present application will become more apparent by reading the detailed description of non-limiting embodiments made with reference to the following drawings:

FIG. 1 is a schematic structural diagram of an automatic focusing device.

FIG. 2 is a schematic diagram of the optical system of the digital autocollimation theodolite.

FIG3 is a schematic diagram of the collimation measurement principle.

FIG4 is a basic structural diagram of the optical system of a digital autocollimation theodolite.

Numbers in the figure: 1, main barrel; 2, objective lens group; 3, electric drive; 4, focusing lens barrel; 5, threaded seat; 6, threaded shaft; 7, first telephoto objective lens; 8, second telephoto objective lens; 9, objective lens seat; 10, objective lens frame; 11, objective lens spacer; 12, objective lens cover; 13, aperture; 14, first focusing lens; 15, second focusing lens; 16, focusing lens seat; 17, focusing lens tube; 18, spring sheet; 19, objective lens pressure ring; 20, hundred-meter ring; 21, focusing nail; 22, focusing wire ring; 23, Image transfer prism; 24, first LED light source; 25, first frosted glass; 26, first graticule; 27, first right-angle prism; 28, first beam splitter prism; 29, second beam splitter prism; 30, autocollimating reflector; 31, second graticule; 32, second frosted glass; 33, second LED light source; 34, second right-angle prism; 35, first CCD focusing lens; 36, filter; 37, second CCD focusing lens; 38, first eyepiece; 39, second eyepiece; 40, third eyepiece;

101. reflector to be measured; 102. optical system; 103. receiving CCD target surface;

201, reflecting mirror; 202, first objective lens; 203, second objective lens; 204, third objective lens; 205, sensor.

DETAILED DESCRIPTION

The present application will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the relevant inventions, rather than to limit the inventions. It should also be noted that, for ease of description, only the parts related to the invention are shown in the accompanying drawings.

It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

Example 1

Please refer to FIG. 1 , which is a schematic structural diagram of a first embodiment of a digital autocollimation theodolite optical system with an automatic focusing function provided by the present application.

The optical system can realize a photoelectric self-collimation function with higher precision through automatic focusing, and can realize automatic measurement and data analysis of misalignment angles. At the same time, it can also automatically focus to a measuring point mode and realize automatic focusing alignment according to different distance values;

The optical system is specially designed to achieve a substantial increase in the focal length of the autocollimation optical path while keeping the total length of the lens barrel unchanged, thus achieving high-precision autocollimation angle measurement. At the same time, the automatic acquisition of CCD images effectively avoids measurement errors caused by eye fatigue and different parallaxes of the human eye during the optical autocollimation process. It is equipped with professional measurement and data analysis software, which can quickly provide analysis results.

The optical system comprises:

An automatic focusing device, the automatic focusing device comprising:

The objective lens assembly comprises: a main barrel 1; the main barrel 1 has a first section and a second section, the first section is provided with an objective lens group 2; the second section is provided with a driving member 3 on an outer wall close to the first section;

A focusing assembly, the focusing assembly comprising: a focusing lens barrel 4; the focusing lens barrel 4 is sleeved on the second section; a focusing lens group is arranged inside the focusing lens barrel 4; and a threaded seat 5 is arranged on the outer wall of the focusing lens barrel 4;

The driving shaft of the driving member 3 is threadedly connected to the threaded seat 5 through the threaded shaft 6; when the driving member 3 is in motion, the threaded shaft 6 is driven to rotate, and the relative position between the threaded shaft 6 and the threaded seat 5 is adjusted, so that the relative position between the main barrel 1 and the focusing lens barrel 4 is changed, so as to adjust the focal length between the objective lens group 2 and the focusing lens group;

A visual optical self-collimation component, the visual optical self-collimation component comprising: a first LED light source 24, a first frosted glass 25, a first grating plate 26, a first right-angle prism 27, a first beam splitter prism 28, a second beam splitter prism 29, an objective lens group 2, a self-collimating reflector 30, a focusing lens group, an image transfer prism 23, a second grating plate 31 and an eyepiece group; a second frosted glass 32 and a second LED light source 33 are sequentially arranged below the first grating plate 26;

A control unit is electrically connected to the driving member 3. The control unit sends a control instruction to the driving member 3. The driving member 3 receives the control instruction and rotates according to the control instruction, so that the threaded shaft 3 can be extended and retracted in the threaded seat 5. When the focal length between the objective lens group 2 and the focusing lens group reaches a preset focal length value, the driving member 3 stops moving, and the driving shaft of the driving member 3 locks the relative position of the threaded shaft 6 and the threaded seat 5. The corresponding relationship between the moving position and the focal length is determined by prior calibration, and the start and stop of the driving member 3 is controlled by the control unit according to the ranging value to further improve the degree of automation of focusing.

In this embodiment, as shown in FIG1 , the automatic focusing device includes:

The objective lens assembly comprises: a main barrel 1, which is a main bearing component of the automatic focusing device, and has a first section and a second section, wherein the first section is composed of a rectangular shape and a trapezoidal shape, and the second section is in a rectangular shape, and the first section is used to install an objective lens group 2 and an aperture 13; a driving member 3 can be installed on the outer wall of the second section, and the second section can be rotatably connected to a focusing lens barrel 4;

A driving member 3 is arranged on the outer wall of the second section close to the first section, and the driving member 3 has a driving shaft for driving the threaded shaft 6 to rotate;

The type of the driving component 3 may be an electric driving motor.

The focusing assembly includes: a focusing lens barrel 4, which is sleeved on the second section, and the outer wall of the focusing lens barrel 4 is provided with a threaded seat 5, the threaded seat 5 is threadedly connected to the threaded shaft 6, and the driving shaft of the driving member 3 is connected to one end of the threaded shaft 6, so that the focusing lens barrel 4 and the main barrel 1 have an indirect connection relationship.

When the driving member 3 is in motion, it can drive the threaded shaft 6 to rotate, so that the relative position between the threaded shaft 6 and the threaded seat 5 changes, and then the relative position between the main tube 1 and the focusing lens barrel 4 changes to adjust the focal length between the objective lens group 2 and the focusing lens group.

Compared with ordinary theodolites, photoelectric autocollimation theodolites can achieve a more accurate photoelectric autocollimation function through automatic focusing, and can realize automatic measurement and data analysis of misalignment angles. At the same time, they can also automatically focus to the measuring point mode and realize focusing alignment according to different distance values. The accuracy of autocollimation is proportional to the focal length of the optical lens, that is, the longer the focal length, the higher the optical resolution, and the higher the measurement accuracy. The optical system of the photoelectric autocollimator is specially designed to achieve a significant increase in the focal length of the autocollimation optical path while keeping the total length of the lens barrel unchanged, thereby achieving high-precision autocollimation angle measurement. At the same time, the use of CCD image automatic acquisition effectively avoids the measurement errors caused by human eye fatigue and different human eye parallax during the optical autocollimation process. Equipped with professional measurement and data analysis software, it can quickly give analysis results.

Compared with the traditional photoelectric autocollimator, on the basis of ensuring the high precision of the autocollimator, the photoelectric autocollimator can be made more portable and convenient to use, and can be used in different sites. The functions are more diverse. At the same time, the photoelectric autocollimator can realize the mutual aiming and positioning of multiple instruments to complete the combined measurement of complex angles.

Compared with traditional manual operation, the optical system of the digital autocollimation theodolite adopts a drive component and a screw transmission method to accurately adjust the focal length between the objective lens group 2 and the focusing lens group, which can improve the detection efficiency and accuracy while also improving the automation level of the system.

In addition, the digital autocollimation theodolite optical system is provided with a control unit, which is electrically connected to the driving member 3. The control unit sends a control instruction to the driving member 3, and the driving member 3 receives the control instruction and rotates according to the control instruction, so that the threaded shaft 6 is extended and retracted in the threaded seat 5. When the focal length between the objective lens group 2 and the focusing lens group reaches a preset focal length value, the driving member 3 stops moving, and the driving shaft of the driving member 3 locks the relative position of the threaded shaft 6 and the threaded seat 5. The start and stop of the driving member 3 is controlled by the control unit to further improve the degree of automation of focusing.

It is also possible to write relevant data conversion interfaces according to the requirements of the measurement tasks, realize real-time and rapid analysis and storage of measurement data, and integrate the collection, analysis, feedback, and storage of measurement data, which can greatly improve the efficiency of related installation, calibration, and precision testing work.

Furthermore, the objective lens group 2 includes: a first telephoto objective lens 7 and a second telephoto objective lens 8, the first telephoto objective lens 7 is arranged away from the focusing lens barrel 4 relative to the second telephoto objective lens 8; and, as shown in Figure 1, a lens pressing ring 19 is provided on the side of the second telephoto objective lens 8 away from the first telephoto objective lens 7 for fixing the second telephoto objective lens 8.

Furthermore, the objective lens assembly also includes:

The objective lens seat 9 is arranged at a position close to the free end of the first section; the objective lens seat 9 is provided with a mounting channel for mounting the objective lens pressing ring 19, the first telephoto objective lens 7 and the second telephoto objective lens 8;

The objective lens frame 10 is arranged at the free end of the first section, and an installation space is formed between the objective lens frame 10 and the first section for installing the objective lens seat 9; wherein the 100-meter ring 20 is arranged between the objective lens frame 10 and the objective lens seat 9, and has a fine-tuning decompression function to prevent excessive extrusion when the objective lens frame 10 is fastened to the main tube 1. Here, the type of the 100-meter ring 20 can be a plastic gasket.

The objective lens spacer 11 is arranged at the gap between the first telephoto objective lens 7 and the second telephoto objective lens 8, and is used to limit the positions of the first telephoto objective lens 7 and the second telephoto objective lens 8 to avoid loosening and wear;

The objective lens cover 12 is arranged outside the objective lens frame 10. When the device is not in use, the objective lens cover 12 can be used to cover the objective lens group 2 to play a protective role.

The aperture 13 is arranged inside the first section and is located between the objective lens group 2 and the focusing lens group, and is used to limit the size of the light beam or the field of view.

The focusing lens group includes: a first focusing lens 14 and a second focusing lens 15 . The first focusing lens 14 is arranged relative to the second focusing lens 15 and close to the second telephoto objective lens 8 .

The focusing components also include:

The focusing lens seat 16 is located in the focusing lens barrel 4 and connected to the inner wall of the focusing lens barrel 4; a mounting surface is formed on one side of the focusing lens seat 16 close to the second telephoto objective lens 8 for mounting the second focusing lens 15;

A focusing lens tube 17 is arranged on the focusing lens seat 16 and is close to the second telephoto lens 8. The first focusing lens 14 is installed inside the focusing lens tube 17;

The focusing lens tube 17 is connected to the focusing lens barrel 4 via a focusing pin 21 , and a focusing wire ring 22 is sleeved on the end of the focusing pin 21 to prevent damage to the glass window when the metal parts are fastened during the focusing process.

The spring sheet 18 is disposed between the first focusing lens 14 and the second focusing lens 15 , and has a protective function, and can separate the first focusing lens 14 from the second focusing lens 15 .

Furthermore, as shown in FIG2 , it also includes:

The focus-adjustable zoom system comprises: an objective lens group 2, a focusing lens group, an image transfer prism 23 and an eyepiece group;

The focusing lens group includes: a first focusing lens 14 and a second focusing lens 15, and the first focusing lens 14 is arranged relatively close to the second graticule 31;

The eyepiece assembly includes a first eyepiece 38 , a second eyepiece 39 and a third eyepiece 40 which are arranged in sequence. The first eyepiece 38 is arranged relatively close to the image relay prism 23 .

The autocollimation optical system includes: a visual optical autocollimation component and a photoelectric autocollimation component;

The visual optical autocollimation assembly includes: a first LED light source 24, a first frosted glass 25, a first grating plate 26, a first right angle prism 27, a first beam splitter prism 28, a second beam splitter prism 29, an objective lens group 2, an autocollimation reflector 30, a focusing lens group, an image transfer prism 23, a second grating plate 31 and an eyepiece group; a second frosted glass 32 and a second LED light source 33 are arranged in sequence below the first grating plate 26;

By adjusting the focusing lens group, the object distance of the objective lens group 2 is set to infinity, and the cross image of the first graticule plate 26 is imaged on the second graticule plate 31, and the twenty characters overlap to achieve optical self-collimation;

The photoelectric autocollimation assembly includes: a first LED light source 24, a first frosted glass 25, a first graticule 26, a first right-angle prism 27, a first beam splitter prism 28, a second beam splitter prism 29, an objective lens group 2, an autocollimation reflector 30, a second right-angle prism 34, a first CCD focusing lens 35, a filter 36 and a second CCD focusing lens 37. In addition, the first telephoto objective lens 7 is relatively close to the autocollimation reflector 30.

Among them, the first frosted glass 25 and the second frosted glass 32 are used to homogenize the light of the corresponding LED light sources to ensure the imaging quality; the first LED light source 24 and the second LED light source 33 are both illumination light sources, the first LED light source 24 can be a red light illumination light source, used to generate a red cross light; the second LED light source 33 can be a white light illumination light source, providing illumination for system observation.

The optical path formed by the focus-adjustable zoom system sequentially passes through the first telephoto objective lens 7, the second telephoto objective lens 8, the first focusing lens 14, the second focusing lens 15, the image transfer prism 23, the first eyepiece 38, the second eyepiece 39 and the third eyepiece 40;

The optical path formed by the visual optical autocollimation assembly sequentially passes through the first LED light source 24, the first ground glass 25, the first graticule 26, the first right angle prism 27, the first beam splitter prism 28, the second beam splitter prism 29, the second telephoto objective lens 8, the first telephoto objective lens 7, the autocollimation reflector 30, the first telephoto objective lens 7, the second telephoto objective lens 8, the second beam splitter prism 29, the first beam splitter prism 28, the first focusing lens 14, the second focusing lens 15, the image transfer prism 23, the second graticule 31, the first eyepiece 38, the second eyepiece 39 and the third eyepiece 40;

The optical path formed by the photoelectric autocollimation assembly passes through the following devices in sequence: the first LED light source 24, the first frosted glass 25, the first graticule 26, the first right-angle prism 27, the first beam splitter prism 28, the second beam splitter prism 29, the second telephoto objective lens 8, the first telephoto objective lens 7, the autocollimation reflector 30, the first telephoto objective lens 7, the second telephoto objective lens 8, the second beam splitter prism 29, the second right-angle prism 34, the first CCD focusing lens 35, the filter 36 and the second CCD focusing lens 37.

The crosshair image of the first graticule plate 26 is directly imaged onto the second CCD focusing lens 37. If the crosshair image coincides with the reference crosshair of the second CCD focusing lens 37, self-collimation is achieved.

Specifically, the principle of the autocollimation optical system is based on the principle of optical autocollimation. As shown in FIG3 , when the reflector 101 has an angle error of θ, the reflected light path of the optical system 102 will have an angle error of 2θ, and the autocollimation image on the receiving target surface 103 will produce a displacement of x on the image plane.

x＝f·tan2θ；(1)

The measurement resolution of the autocollimator is determined by the adjacent pixel spacing d (mm), the focal length f' (mm) of the imaging system, and the number of sub-pixel subdivisions N of the receiving device, that is:

Since the comprehensive accuracy of autocollimation must reach 1", the resolution of autocollimation must be at least 0.1". The corresponding CCD focusing lens receives an increased resolution, and the focal length of the autocollimation optical path needs to be lengthened. Since the shared optical path between the autocollimation optical system and the focusing zoom system is limited by the tube length of the automatic focusing device, the focal length of the focusing objective lens cannot meet the focal length requirements of the autocollimation optical path. Therefore, a lens group is added to the CCD imaging receiving optical path to increase the focal length of the optical path.

_Φtotal =Φ ₁ +Φ ₂ -d·Φ ₁ Φ ₂ ; (3)

Among them, Φtotal _is the total optical focal length of the received optical path after adjustment, _Φ1 is the optical focal length of the shared optical path, _Φ2 is the optical focal length of the lens group added later, and d is the distance between the main surfaces of the two lens groups.

According to the above collimation measurement principle, as shown in FIG4 , the system is composed of a reflector 201, a first objective lens 202, a second objective lens 203, a third objective lens 204, and a sensor 205; wherein the reflector 201 is the object to be measured, and is transmitted to the sensor 205 after passing through the first objective lens 202, the second objective lens 203, and the third objective lens 204. Assuming that the reflector 201 produces an angle deflection of θ, it is known from the optical principle that the reflected light and the incident light will produce a deflection of 2θ, then

Wherein, _H2 is the height of the light spot position at the focal plane of the first objective lens 202 deviating from the optical axis after the reflected light spot passes through the first objective lens 202, and _H3 is the height of the light spot position at the focal plane of the third objective lens 204 deviating from the optical axis after the reflected light spot passes through the third objective lens 204;

In the optical path, θ ₁ = θ ₂ , then

The resolution of this system is:

Where Δh is the detector resolution and ρ is the conversion coefficient, which is 206265.

Furthermore, the image transfer prism 23 is a Porro prism, which is formed by gluing three right-angle prisms; the first beam splitter prism 28 and the second beam splitter prism 29 are both formed by gluing four right-angle prisms, and the processing tolerance of a single prism must be rigorously designed to ensure that the processing difficulty and the design standard are in line with each other to avoid deflection of the incident light axis and the output light axis.

Generally, the prism angle error that causes the optical axis to deflect is divided into the first parallel error θ _Ι between the exit plane and the incident plane, and the second parallel error θ _II caused by the prism error. The deflection of the exit optical axis is divided into two orthogonal components for analysis. Among them, the deflection caused by the first parallel error is δ _Ι , and the deflection caused by the second parallel error is δ _II , then

δ _Ι =nθ _Ι +Δω _Ι ; (9)

δ _II =nθ _II +Δω _II ; (10)

Wherein, Δω _Ι is the deflection angle of the normal line of the exit surface in the optical axis section, and Δω _II is the deflection angle of the normal line of the exit surface in the plane perpendicular to the optical axis section.

The design tolerance of the reflecting prism is given based on the analysis of the optical axis deflection caused by the above prism parallelism error.

When the prism is located between the graticule and the objective lens in the system, the relationship between the prism processing error and the optical axis deflection is:

Where, Γ is the magnification of the telescope system in the optical system;

The processing angle error of the reflecting prism is related not only to the deflection of the optical axis but also to the chromatic aberration of the system. The dispersion expression of the reflecting prism is:

δ′ _CF =(n _F -n _C )·θ; (12)

The chromatic aberration caused by prism processing error is

Among them, n _F and n _C are the refractive indices of light of different wavelengths in the prism, among which n _F is the refractive index corresponding to light of relatively short wavelength, and n _C is the refractive index of light of relatively long wavelength in the prism;

Assume that the total optical axis offset allowed by the system is _δ′total , and let _δ′Ιtotal = _δ′IItotal , then

Based on the above analysis of the relationship between prism processing error, optical axis deflection and chromatic aberration, the tolerance range required for prism design can be quantitatively calculated.

According to the optical path shown in Figure 3, the optical elements that can produce chromatic aberration include the focusing objective lens, the erecting prism, the beam splitter prism and the eyepiece, then K = 4, and the dispersion angle is set to be less than 0.5', then the chromatic aberration allowable value of each part is

The erecting prism and the beam splitter are located between the objective lens and the graticule. According to formula (2), the focal length of the objective lens is 8.09, the distance between the erecting prism and the beam splitter is L ₁ = 10 mm, the distance between the beam splitter and the graticule is L ₂ = 20 mm, and n _F -n _C = 806 × 10 ^-5 is substituted into formula (2) to obtain

Make the first parallelism and the second parallelism of the erecting prism and the beam splitter prism equal, then we get

Since the erector is composed of three right-angle prisms and the beam splitter is composed of four right-angle prisms,

Based on the above calculation and analysis, the tolerance given for the erecting prism and the single small right-angle prism of the beam splitter is

From the above, it can be seen that the optical collimation measurement principle in the present invention is based on the angle change after the light beam is reflected. The measurement method of the non-imaging photoelectric collimator, the system resolution without software processing is greatly improved compared with the resolution of the previous optical system. The output system and the receiving system of the autocollimation system share the same optical path, which reduces one imaging optical path, greatly simplifies the optical structure of the entire system, and reduces the external dimensions of the instrument. At the same time, the optical imaging autocollimation optical path of the theodolite and the autocollimation optical path of the autocollimator can be adjusted independently and can also be verified with each other, which greatly simplifies the adjustment difficulty of the previous system. It not only realizes the telephoto function, but also can perform high-precision collimation angle measurement. Through the electric adjustment mirror group, the telephoto electric focusing is also realized, and the target aiming function can be performed.

The above description is only a preferred embodiment of the present application and an explanation of the technical principles used. Those skilled in the art should understand that the scope of the invention involved in the present application is not limited to the technical solution formed by a specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the inventive concept. For example, the above features are replaced with the technical features with similar functions disclosed in this application (but not limited to) by each other.

Claims (10)

1. A digital autocollimation theodolite optical system with automatic focusing function, characterized in that: The optical system can realize a photoelectric self-collimation function with higher precision through automatic focusing, and can realize automatic measurement and data analysis of misalignment angles. At the same time, it can also automatically focus to a measuring point mode and realize automatic focusing alignment according to different distance values; The optical system achieves a substantial increase in the focal length of the autocollimation optical path while keeping the total length of the lens barrel unchanged, thereby achieving high-precision autocollimation angle measurement. At the same time, the automatic acquisition of CCD images effectively avoids measurement errors caused by eye fatigue and different parallaxes of the human eye during the optical autocollimation process. The system is equipped with measurement and data analysis software, which can quickly provide analysis results. The optical system comprises: An automatic focusing device, the automatic focusing device comprising: An objective lens assembly, the objective lens assembly comprising: a main barrel (1); the main barrel (1) having a first section and a second section, the first section being provided with an objective lens group (2); the second section being provided with a driving member (3) on an outer wall close to the first section; A focusing assembly, the focusing assembly comprising: a focusing lens barrel (4); the focusing lens barrel (4) is sleeved on the second section; a focusing lens group is provided inside the focusing lens barrel (4); and a threaded seat (5) is provided on the outer wall of the focusing lens barrel (4); The driving shaft of the driving member (3) is threadedly connected to the threaded seat (5) via a threaded shaft (6); when the driving member (3) is in motion, the threaded shaft (6) is driven to rotate, and the relative position between the threaded shaft (6) and the threaded seat (5) is adjusted, so that the relative position between the main barrel (1) and the focusing lens barrel (4) is changed, so as to adjust the focal length between the objective lens group (2) and the focusing lens group; A visual optical self-collimation component, the visual optical self-collimation component comprising: a first LED light source (24), a first frosted glass (25), a first dividing plate (26), a first right-angle prism (27), a first beam splitter prism (28), a second beam splitter prism (29), an objective lens group (2), a self-collimating reflector (30), a focusing lens group, an image transfer prism (23), a second dividing plate (31) and an eyepiece group; a second frosted glass (32) and a second LED light source (33) are sequentially arranged below the first dividing plate (26); A control unit is electrically connected to the driving member (3). The control unit sends a control instruction to the driving member (3). The driving member (3) receives the control instruction and rotates according to the control instruction, so that the threaded shaft (3) is extended and retracted in the threaded seat (5). When the focal length between the objective lens group (2) and the focusing lens group reaches a preset focal length value, the driving member (3) stops moving, and the driving shaft of the driving member (3) locks the relative position of the threaded shaft (6) and the threaded seat (5). The corresponding relationship between the moving position and the focal length is determined by pre-calibration, and the start and stop of the driving member (3) is controlled by the control unit according to the distance measurement value to adjust the focus, so as to further improve the degree of automation of focusing. 2. A digital autocollimation theodolite optical system with automatic focusing function according to claim 1, characterized in that the driving component (3) is an electric driving motor. 3. A digital autocollimation theodolite optical system with automatic focusing function according to claim 1, characterized in that the objective lens group (2) comprises: a first telephoto objective lens (7) and a second telephoto objective lens (8), and the first telephoto objective lens (7) is arranged away from the focusing lens barrel (4) relative to the second telephoto objective lens (8). 4. The digital autocollimation theodolite optical system with automatic focusing function according to claim 3, characterized in that the objective lens assembly further comprises: An objective lens seat (9) is arranged at a position close to the free end of the first section; the objective lens seat (9) is provided with a mounting channel for mounting the first telephoto objective lens (7) and the second telephoto objective lens (8); An objective lens frame (10) is arranged at the free end of the first section, and an installation space is formed between the objective lens frame (10) and the first section for installing an objective lens seat (9); An objective lens spacer (11) arranged at the gap between the first telephoto objective lens (7) and the second telephoto objective lens (8); An objective lens cover (12), which is arranged outside the objective lens frame (10); An aperture (13) is arranged inside the first section, and the aperture (13) is located between the objective lens group (2) and the focusing lens group. 5. The digital autocollimation theodolite optical system with automatic focusing function according to claim 3 or 4, characterized in that the focusing lens group comprises: A first focusing lens (14) and a second focusing lens (15), wherein the first focusing lens (14) is arranged relative to the second focusing lens (15) and close to the second telephoto objective lens (8). 6. The digital autocollimation theodolite optical system with automatic focusing function according to claim 5, characterized in that the focusing component further comprises: A focusing lens seat (16) is located in the focusing lens barrel (4) and connected to the inner wall of the focusing lens barrel (4); a mounting surface is formed on a side of the focusing lens seat (16) close to the second telephoto objective lens (8) for mounting the second focusing lens (15); A focusing lens tube (17) is arranged on the focusing lens seat (16) and is close to the second telephoto objective lens (8), and the first focusing lens (14) is installed inside the focusing lens tube (17); The spring sheet (18) is arranged between the first focusing mirror (14) and the second focusing mirror (15). 7. The digital autocollimation theodolite optical system with automatic focusing function according to claim 1, characterized in that it also includes: A focus-adjustable zoom system, the focus-adjustable zoom system comprising: an objective lens group (2), a focusing lens group, an image transfer prism (23) and an eyepiece group; An autocollimation optical system, the autocollimation optical system comprising: a visual optical autocollimation component and a photoelectric autocollimation component; The visual optical autocollimation assembly comprises: a first LED light source (24), a first frosted glass (25), a first grating plate (26), a first right-angle prism (27), a first beam splitter prism (28), a second beam splitter prism (29), an objective lens group (2), a self-collimating reflector (30), a focusing lens group, an image transfer prism (23), a second grating plate (31) and an eyepiece group; a second frosted glass (32) and a second LED light source (33) are arranged in sequence below the first grating plate (26); The photoelectric self-collimation component comprises: a first LED light source (24), a first frosted glass (25), a first graticule (26), a first right-angle prism (27), a first beam splitter prism (28), a second beam splitter prism (29), an objective lens group (2), a self-collimating reflector (30), a second right-angle prism (34), a first CCD focusing lens (35), a filter (36) and a second CCD focusing lens (37). 8. A digital autocollimation theodolite optical system with automatic focusing function according to claim 7, characterized in that the first telephoto objective lens (7) is arranged relatively close to the autocollimation reflector (30). 9. A digital autocollimation theodolite optical system with automatic focusing function according to claim 8, characterized in that the eyepiece group comprises: a first eyepiece (38), a second eyepiece (39) and a third eyepiece (40) arranged in sequence, the first eyepiece (38) being arranged relatively close to the image relay prism (23); The image transfer prism (23) is a Porro prism, which is formed by gluing three right-angle prisms together; the first beam splitter prism (28) and the second beam splitter prism (29) are both formed by gluing four right-angle prisms together, and the processing tolerance of a single prism is designed to achieve a mutual fit between the processing difficulty and the design standard, thereby avoiding deflection of the incident light axis and the output light axis. 10. The digital autocollimation theodolite optical system with automatic focusing function according to claim 7, characterized in that the focusing lens group comprises: a first focusing lens (14) and a second focusing lens (15), and the first focusing lens (14) is arranged relatively close to the second graticule (31).

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