Optical axis verticality detection method

Abstract

The present invention provides an optical axis verticality detection method, which mainly adopts a self-collimating light tube, a cubic prism and a refracting mirror to solve the problem of optical axis verticality detection of a dual optical axis system, and mainly includes the following steps: the first step, vertical alignment of the first self-collimating light tube and the second self-collimating light tube, and self-collimation of the first self-collimating light tube and the second self-collimating light tube with mutually perpendicular surfaces of the cubic prism respectively; the second step, verticality detection of the optical axis, placing a refracting mirror in the direction of the incident light path of the second self-collimating light tube, aligning the second optical axis with the incident surface of the refracting mirror, aligning the light inlet of the second self-collimating light tube with the light exit surface of the refracting mirror, recording the readings and calculating the errors. The equipment used in the present invention are all commonly used devices in optical inspection, with high precision, low cost and easy adjustment. The optical axis verticality detection method of the present invention is simple to operate, high in accuracy, and applicable to various complex environments.

Description

Technical Field

[0001] The invention relates to the field of optical detection, and specifically provides an optical axis verticality detection method based on a dual optical axis system. Background Art

[0002] When measuring the three-dimensional posture of the target, a dual optical axis system is required. In order to meet the measurement accuracy requirements, the verticality of the two optical axes is usually required to be kept within 10", so the verticality of the two optical axes needs to be detected.

[0003] At present, the most common method for detecting the verticality of the optical axis of a dual optical axis system is to use two high-precision autocollimation theodolites that can be adjusted. Figure 3 As shown, firstly, the two autocollimation theodolites are adjusted to be horizontal, and when the pitch angle is 90°, the apertures are respectively aligned with the first optical axis 5 and the second optical axis 6, and the first autocollimation theodolite 7 is aligned with the first optical axis 5. At this time, the azimuth value of the first autocollimation theodolite 7 is cleared to zero, and then the first autocollimation theodolite 7 is rotated counterclockwise at an azimuth angle θ, and the second autocollimation theodolite 8 is rotated clockwise at an appropriate angle, and the pitch angle is adjusted to make the two autocollimation theodolites mutually aligned, and then the first autocollimation theodolite is rotated clockwise at an azimuth angle θ, and the pitch angle is adjusted to 90°, and the second autocollimation theodolite 8 is rotated counterclockwise at an azimuth angle of 90°-θ, and the pitch angle is adjusted to 90°. At this time, the optical axes of the two autocollimation theodolites are perpendicular to each other and parallel to the horizontal plane. The azimuth reading α0 and the height reading β0 of the second autocollimation theodolite 8 are recorded at this time, and then the second autocollimation theodolite 8 is self-aligned with the second optical axis 6. At this time, the azimuth reading α'0 and the height reading β'0 of the second autocollimation theodolite 8 are measured. The horizontal error △α0=α'0-α0 is the vertical error between the second optical axis 6 and the first optical axis 5, and the height direction error △β0=β'0-β0 is the error between the second optical axis 6 and the horizontal plane in the height direction. However, the high-precision autocollimation theodolite used in the existing detection method is a special measuring device with high equipment cost. Summary of the invention

[0004] In order to solve the above problems, the present invention provides a method for detecting the verticality of an optical axis, which mainly adopts an autocollimating light tube, a cubic prism and a refracting mirror to solve the problems of high cost and complicated operation of the traditional method of detecting the verticality of the optical axis of a dual optical axis system using an autocollimating theodolite.

[0005] The optical axis verticality detection method provided by the present invention comprises the following steps:

[0006] S1, vertical alignment of the first autocollimating light pipe and the second autocollimating light pipe;

[0007] Step S11, adjusting the cubic prism to a horizontal state, so that adjacent faces of the cubic prism are perpendicular to each other;

[0008] Step S12, respectively aligning the first autocollimator and the second autocollimator with two mutually perpendicular surfaces of the cubic prism, and recording the reference readings of the first autocollimator, including: a first horizontal reference reading α1 and a first high-low reference reading β1; recording the reference readings of the second autocollimator, including: a second horizontal reference reading α2 and a second high-low reference reading β2;

[0009] S2. Detection of verticality of optical axis;

[0010] Step S21, remove the cubic prism to align the first autocollimation light tube with the first optical axis, and record the measurement readings of the first autocollimation light tube at this time, including: a first horizontal measurement reading α'1 and a first high and low measurement reading β'1;

[0011] Step S22, placing a folding mirror in the direction of the incident light path of the second self-collimating light tube, the folding mirror is used to fold the incident light back in parallel by 180°;

[0012] Step S23, aligning the second optical axis with the light incident surface of the folding mirror, aligning the light inlet of the second autocollimator with the light exit surface of the folding mirror, aligning the second autocollimator with the second optical axis, and recording the measurement readings of the second autocollimator at this time, including: a second horizontal measurement reading α'2 and a second high and low measurement reading β'2;

[0013] Step S24, calculate the vertical error Δα between the first optical axis and the second optical axis as follows:

[0014] △α=(α'1-α1)-(α'2-α2);

[0015] The parallel errors between the first optical axis and the second optical axis and the horizontal plane are calculated as follows:

[0016] △β1=(β'1-β1);

[0017] △β2=(β'2-β2).

[0018] Preferably, the error angle between the first self-collimating light pipe and the second self-collimating light pipe is less than or equal to 0.2″.

[0019] Preferably, the folding mirror is a combination of two pentaprisms or two plane mirrors.

[0020] Compared with the prior art, the present invention can achieve the following beneficial effects:

[0021] The present invention solves the problem of optical axis verticality detection of a dual optical axis system by only using a self-collimating light tube, a cubic prism, and a folding prism. The equipment used are all commonly used devices in optical inspection, with high precision, low cost, and easy adjustment. The optical axis verticality detection method of the present invention is simple to operate, highly accurate, and applicable to various complex environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is a schematic diagram of an optical path alignment of an optical axis verticality detection method provided in an embodiment of the present invention;

[0023] Figure 2 is a schematic diagram of an optical path of a method for detecting verticality of an optical axis provided in an embodiment of the present invention;

[0024] Figure 3 The invention is a schematic diagram of a self-collimating theodolite used in the background technology to self-align and measure the perpendicular optical paths of two optical axes.

[0025] The reference numerals include: a first autocollimating light tube 1 , a second autocollimating light tube 2 , a cubic prism 3 , a folding mirror 4 , a first optical axis 5 , a second optical axis 6 , a first autocollimating theodolite 7 , and a second autocollimating theodolite 8 . DETAILED DESCRIPTION

[0026] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the following description, the same modules are represented by the same reference numerals. In the case of the same reference numerals, their names and functions are also the same. Therefore, the detailed description thereof will not be repeated.

[0027] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and do not constitute a limitation of the present invention.

[0028] The present invention adopts a first self-collimating light tube 1, a second self-collimating light tube 2, a cubic prism 3 and a folding mirror 4 to solve the problem of optical axis verticality detection of a dual optical axis system, wherein the angle error between the first self-collimating light tube 1 and the second self-collimating light tube 2 is less than or equal to 0.2″; adjacent surfaces of the cubic prism 3 are perpendicular to each other; the folding mirror 4 is used to fold the incident light back 180° in parallel, and a combination of two pentaprisms or two plane mirrors can be selected.

[0029] The optical axis verticality detection method provided in this embodiment includes the following steps:

[0030] S1, vertically align the first auto-collimating light pipe 1 and the second auto-collimating light pipe 2.

[0031] Figure 1 The collimated optical path of the optical axis verticality detection method provided according to an embodiment of the present invention is shown.

[0032] like Figure 1 As shown, the vertical alignment of the first self-collimating light pipe 1 and the second self-collimating light pipe 2 includes the following steps:

[0033] Step S11, adjust the cubic prism 3 to a horizontal state at an appropriate position and keep it still, the a face and the b face of the cubic prism 3 are perpendicular to each other and parallel to the horizontal plane, the cubic prism 3 is a standard device, and the angle between two adjacent faces is 90°.

[0034] Step S12, prepare two autocollimation light tubes, auto-align the first autocollimation light tube 1 with the a-plane of the cubic prism 3 at an appropriate position, read out the horizontal reference reading α1 and the height reference reading β1 of the first autocollimation light tube 1; then auto-align the second autocollimation light tube 2 with the b-plane of the cubic prism 3, read out the horizontal reference degree α2 and the height reference reading β2 of the second autocollimation light tube 2, keep the positions of the first autocollimation light tube 1 and the second autocollimation light tube 2 unchanged, at this time, the incident light paths of the first autocollimation light tube 1 and the second autocollimation light tube 2 are perpendicular to each other and parallel to the horizontal plane.

[0035] S2. Detection of perpendicularity of the first optical axis 5 and the second optical axis 6.

[0036] Figure 2 The optical path of the optical axis verticality detection method provided according to an embodiment of the present invention is shown.

[0037] like Figure 2 As shown, the verticality detection of the first optical axis 5 and the second optical axis 6 includes the following steps:

[0038] Step S21, move the cubic prism 3 out of the field of view of the first autocollimation light tube 1 and the second autocollimation light tube 2, so that the outgoing light of the first optical axis 5 in the dual optical axis system is aligned with the first autocollimation light tube 1, and record the horizontal measurement reading α'1 and the height measurement reading β'1 of the first autocollimation light tube 1 at this time.

[0039] Step S22, placing a folding mirror 4 in the direction of the incident light path of the second self-collimating light tube 2, and the folding mirror 4 can fold the light path parallelly by 180 degrees.

[0040] Step S23, align the second optical axis 6 with the light inlet of the fold mirror 4, align the light inlet of the second autocollimator 2 with the light outlet of the fold mirror 4, and record the horizontal measurement reading α'2 and the height measurement reading β'2 of the second autocollimator 2 at this time.

[0041] Step S24, calculating the vertical error Δα=(α'1-α1)-(α'2-α2), that is, the vertical error between the first optical axis 5 and the second optical axis 6;

[0042] Calculate the parallel errors between the first optical axis 5 and the second optical axis 6 and the horizontal plane respectively: △β1=(β'1-β1), which is the parallel error between the first optical axis 5 and the horizontal plane; △β2=(β'2-β2), which is the parallel error between the second optical axis 6 and the horizontal plane.

[0043] It should be noted that, in this embodiment, the selected devices are all commonly used devices in optical inspection, with high precision, low cost and easy adjustment.

[0044] Although the embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and cannot be understood as limiting the present invention. Those skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

[0045] The above specific implementations of the present invention do not constitute a limitation on the protection scope of the present invention. Any other corresponding changes and modifications made based on the technical concept of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A method for detecting the verticality of an optical axis, characterized in that: The following steps are involved: S1, vertical alignment of the first autocollimating light pipe and the second autocollimating light pipe; Step S11, adjusting the cubic prism to a horizontal state, wherein adjacent faces of the cubic prism are perpendicular to each other; Step S12, respectively aligning the first autocollimator and the second autocollimator with two mutually perpendicular surfaces of the cubic prism, and recording the reference readings of the first autocollimator, including: a first horizontal reference reading α1 and a first high-low reference reading β1; recording the reference readings of the second autocollimator, including: a second horizontal reference reading α2 and a second high-low reference reading β2; S2. Detection of verticality of optical axis; Step S21, removing the cubic prism to align the first autocollimation light tube with the first optical axis, and recording the measurement readings of the first autocollimation light tube at this time, including: a first horizontal measurement reading α'1 and a first high and low measurement reading β'1; Step S22, placing a folding mirror in the direction of the incident light path of the second self-collimating light tube, the folding mirror is used to fold the incident light back in parallel by 180°; Step S23, aligning the second optical axis with the light incident surface of the folding mirror, aligning the light inlet of the second autocollimator with the light exit surface of the folding mirror, aligning the second autocollimator with the second optical axis, and recording the measurement readings of the second autocollimator at this time, including: a second horizontal measurement reading α'2 and a second high and low measurement reading β'2; Step S24, calculating the vertical error Δα between the first optical axis and the second optical axis as follows: △α＝(α'1-α1)-(α'2-α2)； The parallel errors between the first optical axis and the second optical axis and the horizontal plane are calculated as follows: △β1＝(β'1-β1)； △β2＝(β'2-β2)。 2. The optical axis verticality detection method according to claim 1, characterized in that: The error angle between the first self-collimating light pipe and the second self-collimating light pipe is less than or equal to 0.2″.

3. The optical axis verticality detection method according to claim 1, characterized in that: The folding mirror is a combination of two pentaprisms or two plane mirrors.

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