Transparent object angle attitude measurement method and device based on internal reflection

Abstract

The invention relates to the field of angle attitude measurement, in particular to a method and device for measuring the angle attitude of a transparent object, and the method comprises the steps: enabling two sides of the surface of a measured transparent object to have refractive index difference, enabling a light beam to enter from one side of an optically denser medium, carrying out the total internal reflection on the surface of the measured transparent object, and then enabling the light beam to exit to a plane target mirror; after mirror reflection occurs on the surface of the plane target mirror, the light beam enters the surface of the measured transparent object again, after total internal reflection occurs on the surface of the measured transparent object, the included angle between the optical axis of the light beam and the original optical axis is measured, and the angle posture of the measured transparent object is calculated; the device comprises a base, a light source, a beam splitter prism, a collimator objective, a photoelectric detector and a plane target mirror. The collimated light beam is reflected on a transparent plane by using a total internal reflection phenomenon, so that the transmission direction of the collimated light beam contains angle attitude information; calculating the angle attitude of the measured transparent object in combination with the auto-collimation principle; the device cooperates with a plane target lens to realize absolute angle attitude measurement.

Description

Technical Field

[0001] This invention relates to the field of angle and attitude measurement, and in particular to a method and apparatus for measuring the angle and attitude of transparent objects. Background Technology

[0002] An autocollimator is an instrument for measuring minute angles based on the geometric optical object-image relationship. In use, the autocollimator emits a collimated beam, which reflects off the surface of the object being measured and returns along the same path. A photoelectric sensor measures the angle between the optical axis of the returning beam and the original optical axis, reflecting the angular attitude information of the object. Because the same optomechanical system is used to emit and receive the collimated beam, the instrument is called an "autocollimator." The angle between the returning beam's optical axis and the original optical axis is limited by the autocollimation range. When incident on the object's surface, the angle between the wavefront normal vector of the collimated beam and the normal to the object's surface (i.e., the angle of incidence) is typically on the order of microradians to nanoradians. According to Fresnel's equations, at this order of incidence angle, the surface of the object being measured has high transmittance and extremely low reflectivity, and the light energy returning to the autocollimator is insufficient for the measurement requirements. Therefore, an anti-reflective coating must be deposited on the surface of the object being measured, or a plane target mirror must be attached.

[0003] The application of autocollimators in various scenarios is a key research focus in this field. For example, Zhongce Optics (Fujian) Technology Co., Ltd. disclosed a structure and measurement method for measuring right-angle prisms using an autocollimator (CN120122355A). This method separates the reflection images from the hypotenuse and right-angle sides of the right-angle prism within a specific incident angle range, thereby measuring the key angles of the prism. Another example is Chongqing University of Posts and Telecommunications, which disclosed a high-precision liquid refractive index measurement method based on optical autocollimation (CN118583819A). This method designs a liquid-loaded reflector with trapezoidal slope cavity structure characteristics to replace the target plane mirror of a traditional autocollimator, achieving liquid refractive index measurement.

[0004] In recent years, with the development of extreme optics manufacturing, micro-nano lithography, and other fields, transparent optical materials such as flat glass have been commonly used as manufacturing substrates. For example, spaceborne optical platforms utilize a single piece of flat glass, with optical components fixed to its working surface via adhesive or mechanical connections. During the manufacturing and assembly of such transparent optical materials, high-precision angle and attitude measurement and positioning are often required. Traditional contact measurement methods can damage the optical surface; optical methods such as autocollimators and differential laser interferometers are limited by the high transmittance (low reflectance) of transparent optical materials, resulting in extremely poor signal quality and making measurement difficult; bonding or attaching high-reflectivity materials (or planar target mirrors) to the surface may damage the optical surface or lead to extremely high additional costs. Therefore, existing technologies are insufficient for the effective measurement of the angle and attitude of transparent optical materials. Summary of the Invention

[0005] (a) Technical problems to be solved The purpose of this invention is to address the problems in existing technologies by proposing a method and apparatus for measuring the angle and attitude of transparent objects based on internal reflection. The method for measuring the angle and attitude of transparent objects described in this invention ensures that the incident angle of the collimated beam on the surface of the transparent object being measured is greater than the critical angle for total internal reflection. The collimated beam undergoes total internal reflection on the surface of the transparent object, and the optical axis of the reflected beam contains the angle and attitude information of the transparent object. The planar target mirror is no longer attached to the object. When the wavefront of the collimated beam is perpendicular to the normal vector of the planar target mirror, the beam, after specular reflection on the surface of the planar target mirror, returns along its original path to the self-collimating device, providing an absolute zero point for the self-collimating device. The apparatus for measuring the angle and attitude of transparent objects described in this invention utilizes the principle of total internal reflection to enable the collimated beam to reflect on the surface of the transparent object being measured. After reflection on the surface of the transparent object, the collimated beam is incident on the planar target mirror, undergoes specular reflection on the surface of the planar target mirror, returns to the transparent object, and reflects again on the surface of the transparent object before returning. The self-collimation principle is used to measure the angle between the optical axis of the returning beam and the original optical axis, and then the angle and attitude of the object are calculated based on the optical axis angle.

[0006] (II) Technical Solution This invention is achieved through the following technical solution. The invention relates to a method for measuring the angle and attitude of a transparent object. The method is characterized in that there is a difference in refractive index on both sides of the surface of the transparent object being measured. A light beam is incident from one side of the optically dense medium, undergoes total internal reflection on the surface of the transparent object being measured, and then exits to a plane target mirror. After specular reflection on the surface of the plane target mirror, the light beam is incident on the surface of the transparent object being measured again. After total internal reflection on the surface of the transparent object being measured, the angle between the optical axis of the measuring beam and the original optical axis can be used to calculate the angle and attitude of the transparent object being measured.

[0007] Furthermore, the beam remains collimated during transmission.

[0008] Furthermore, the light beam undergoes [a process / effect] on the surface of the transparent object being measured. Secondary total internal reflection .

[0009] Furthermore, when the transparent object being measured is in a specific angular orientation, the normal vector of the plane target mirror is perpendicular to the wavefront of its incident light beam. After specular reflection on the surface of the plane target mirror, the light beam returns along its original path, making an angle with the original optical axis. The zero position is defined as the angle and orientation of the transparent object being measured.

[0010] Furthermore, the system includes a base, a light source, a beam splitter prism, a collimating objective lens, a photodetector, and a plane target mirror. The light source, beam splitter prism, collimating objective lens, photodetector, and plane target mirror are fixed on the base. The light source is placed on one side of the beam splitter prism's beam splitting surface, and the photodetector, collimating objective lens, and plane target mirror are located on the other side of the beam splitter prism's beam splitting surface. The photodetector and the light source are placed symmetrically about the beam splitter prism's beam splitting surface. The transparent object being measured is located between the plane target mirror and the collimating objective lens, the collimating objective lens is located between the plane target mirror and the beam splitter prism, and the beam splitter prism is located between the collimating objective lens and the light source.

[0011] Furthermore, the light emitted from the light source passes through a beam splitter and then enters the collimating objective lens, exiting as a collimated beam. The collimated beam enters the surface of the transparent object being measured from the optically denser medium side, undergoes total internal reflection on the surface of the transparent object, and then enters the plane target mirror. After specular reflection on the surface of the plane target mirror, it enters the surface of the transparent object being measured again, undergoes total internal reflection on the surface of the transparent object, and returns to the collimating objective lens. The collimated beam converges after passing through the collimating objective lens, and this converged beam is focused and imaged on the surface of the photodetector after passing through a beam splitter. The imaging result is transmitted to the computer, and the angle and attitude information of the transparent object being measured can be calculated through image processing algorithms.

[0012] Furthermore, the light emitted by the light source is emitted after passing through the fiber core, or after passing through the fiber core and the aperture, and the types of the aperture include pinhole aperture, slit aperture, and polygonal aperture.

[0013] Furthermore, the beam splitter can be a regular beam splitter, a polarizing beam splitter, or a depolarizing beam splitter.

[0014] Furthermore, photodetectors can be one-dimensional or two-dimensional.

[0015] Furthermore, when the normal vector of the planar target mirror is perpendicular to the wavefront of the beam, the beam returns and focuses at the position of the photodetector. , The angle and orientation of the transparent object being measured at the point is defined as the zero position.

[0016] Furthermore, if a one-dimensional photodetector is used, the deflection angle of the transparent object being measured relative to the zero position is: At that time, the beam returns to the collimator and the focusing position deviates from the photodetector. The distance between the points is ,but , focal length of collimating objective lens The following relationship exists between them:

[0017] in, It is a constant.

[0018] Furthermore, if a two-dimensional photodetector is used, when the transparent object being measured has a pitch angle or a yaw angle relative to the zero position, the focusing position of the two-dimensional photodetector will deviate. Distance between points The projection is onto two orthogonal directions; the pitch angle of the measured transparent object relative to the zero position is... At that time, the beam returns to the collimator and the focusing position deviates from the photodetector. The distance of the point is projected in the corresponding direction as The yaw angle of the transparent object being measured relative to zero position is: At that time, the beam returns to the collimator and the focusing position deviates from the photodetector. The distance of the point is projected in the corresponding direction as ; , and , focal length of collimating objective lens The following relationship exists between them:

[0019] in, It is a constant.

[0020] (III) Beneficial Effects The beneficial effects of this invention are as follows: Utilizing the phenomenon of total internal reflection, the light beam is incident from the side of the optically dense medium onto the surface of the transparent object being measured, and the angle of incidence is greater than the critical angle of total internal reflection. Thus, without coating an anti-reflection film or attaching a plane target mirror, the collimated light beam is reflected on the surface of the transparent object being measured, thereby ensuring that the transmission direction of the collimated light beam contains the angular attitude information of the transparent object being measured. Combining the self-collimation principle, the angle between the optical axis of the returned beam and the original optical axis is measured, and the angular attitude of the transparent object being measured is calculated. Simultaneously, the self-collimation device works in conjunction with the plane target mirror. When the wavefront of the collimated beam is perpendicular to the normal vector of the plane target mirror, the angular attitude of the transparent object being measured is defined as zero, thereby enabling absolute angular attitude measurement. Attached Figure Description

[0021] Figure 1 This is a block diagram of the transparent object angle and attitude measurement method described in this invention; Figure 2 This is an embodiment of the transparent object angle and attitude measuring device described in this invention; Figure 3 This is another embodiment of the transparent object angle and attitude measuring device described in this invention; Figure 4 This is another embodiment of the transparent object angle and attitude measuring device described in this invention; Figure 5This is another embodiment of the transparent object angle and attitude measuring device described in this invention; Figure 6 This is another embodiment of the transparent object angle and attitude measuring device described in this invention. Detailed Implementation

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] First Embodiment Combination Figure 2 This invention proposes an embodiment of a transparent object angle and attitude measurement device. A light source 2, a beam splitter 3, a collimating objective lens 4, and a plane target lens 5 are all fixed on a base 1. The light source 2 is placed on one side of the beam splitter 3, and the photodetector 6, collimating objective lens 4, and plane target lens 5 are located on the other side of the beam splitter 3; the photodetector 6 and the light source 2 are symmetrically placed about the beam splitter 3; the collimating objective lens 4 is located between the plane target lens 5 and the beam splitter 3, and the beam splitter 3 is located between the collimating objective lens 4 and the light source 2; the transparent object 700 to be measured is placed between the collimating objective lens 4 and the plane target lens 5.

[0024] The transparent object 700 under test includes a first transmission plane 710, a second transmission plane 720, a third transmission plane 730, and a fourth transmission plane 740. The first and third transmission planes 710 are parallel to each other, as are the second and fourth transmission planes 720. The first transmission plane 710 is located on the vertical side near the collimating objective lens 4, and the third transmission plane 730 is located on the vertical side away from the collimating objective lens 4. The second transmission plane 720 is located on the side away from the light source 2, and the fourth transmission plane 740 is located on the side near the light source 2.

[0025] The light emitted from light source 2 passes through beam splitter prism 3 and collimating objective lens 4, and exits as a collimated beam. This collimated beam enters through the first transmission plane 710 of the transparent object 700 under test. After total internal reflection at a certain angle on the second transmission plane 720 inside the transparent object 700, it exits through the third transmission plane 730. After specular reflection perpendicular to the surface of the target mirror 5, it re-enters the third transmission plane 730 of the transparent object 700 under test. After total internal reflection at a certain angle on the surface of the second transmission plane 720, it exits through the first transmission plane 710 and returns. The returning collimated beam converges after passing through collimating objective lens 4, is reflected by beam splitter prism 3, and is focused on the surface of photodetector 6. The incident plane, the plane of total internal reflection, and the exit plane are all different planes, with the incident plane parallel to the exit plane.

[0026] When the transparent object 700 being measured does not deflect, the beam returns and focuses on the photodetector 6 at the following position: Point. Photodetector 6 is a one-dimensional photodetector. The deflection angle of the transparent object 700 relative to the zero position is... When the beam returns, it is relatively at the focusing position of photodetector 6. The distance between the points is ,but , With collimating objective lens 4 focal length The following relationship exists between them:

[0027] in, This is a constant. Using this formula, the angle and orientation of the transparent object being measured can be calculated based on the detection results of the photodetector.

[0028] As described in the method for measuring the angle and attitude of transparent objects, the light beam must be incident on the object's surface from the side of the optically denser medium for total internal reflection to occur when the angle of incidence is greater than the critical angle. If the object's material has a negative refractive index, total internal reflection can occur when the light beam is incident on the object's surface from air; this is called external reflection, or total external reflection. However, most object materials have a positive refractive index, so the light beam must first enter the object's interior and then exit from the object's interior into the air for total internal reflection to occur; this is called internal reflection, or total internal reflection.

[0029] Figure 2 , Figure 3 , Figure 5 , Figure 6This demonstrates different methods for measuring the angular attitude of a transparent object 7 using the principle of total internal reflection. The difference lies in the different incident and exit points of the collimated beam onto the surface of the transparent object 7, resulting in different numbers of total internal reflections occurring within the object. Consequently, the relationship between the angle between the returning beam axis and the original beam axis and the angular attitude of the transparent object 7 also differs.

[0030] Second Embodiment Combination Figure 3 This invention proposes an embodiment of a transparent object angle and attitude measurement device. A light source 2, a beam splitter 3, a collimating objective lens 4, and a plane target lens 5 are all fixed on a base 1. The light source 2 is placed on one side of the beam splitter 3, and the photodetector 6, collimating objective lens 4, and plane target lens 5 are located on the other side of the beam splitter 3; the photodetector 6 and the light source 2 are symmetrically placed about the beam splitter 3; the collimating objective lens 4 is located between the plane target lens 5 and the beam splitter 3, and the beam splitter 3 is located between the collimating objective lens 4 and the light source 2; the transparent object 700 to be measured is placed between the collimating objective lens 4 and the plane target lens 5.

[0031] The transparent object 700 under test includes a first transmission plane 710, a second transmission plane 720, a third transmission plane 730, and a fourth transmission plane 740. The first and third transmission planes 710 are parallel to each other, as are the second and fourth transmission planes 720. The first transmission plane 710 is located on the vertical side near the collimating objective lens 4, and the third transmission plane 730 is located on the vertical side away from the collimating objective lens 4. The second transmission plane 720 is located on the side away from the light source 2, and the fourth transmission plane 740 is located on the side near the light source 2.

[0032] The light emitted from light source 2 passes through beam splitter prism 3 and collimating objective lens 4, exiting as a collimated beam. This collimated beam enters through the first transmission plane 710 of the transparent object 700 under test. After total internal reflection at a certain angle within the second transmission plane 720 of the transparent object 700, it exits through the fourth transmission plane 740. After specular reflection perpendicular to the surface of the target mirror 5, it re-enters the fourth transmission plane 740 of the transparent object 700 under test. After total internal reflection at a certain angle within the second transmission plane 720 of the transparent object 700, it exits through the first transmission plane 710 and returns. The returning collimated beam converges after passing through collimating objective lens 4, is reflected by beam splitter prism 3, and is focused on the surface of photodetector 6. Notably, the incident plane, the plane undergoing total internal reflection, and the exit plane are all different planes, with the incident plane perpendicular to the exit plane.

[0033] When the transparent object 700 being measured does not deflect, the beam returns and focuses on the photodetector 6 at the following position: Point. Photodetector 6 is a one-dimensional photodetector. The deflection angle of the transparent object 700 relative to the zero position is... When the beam returns, it is relatively at the focusing position of photodetector 6. The distance between the points is ,but , With collimating objective lens 4 focal length The following relationship exists between them:

[0034] in, This is a constant. Using this formula, the angle and orientation of the transparent object being measured can be calculated based on the detection results of the photodetector.

[0035] Third Embodiment Combination Figure 4 This invention proposes an embodiment of a transparent object angle and attitude measurement device. A light source 2, a beam splitter 3, a collimating objective lens 4, and a plane target lens 5 are all fixed on a base 1. The light source 2 is placed on one side of the beam splitter 3, and the photodetector 6, collimating objective lens 4, and plane target lens 5 are located on the other side of the beam splitter 3; the photodetector 6 and the light source 2 are symmetrically placed about the beam splitter 3; the collimating objective lens 4 is located between the plane target lens 5 and the beam splitter 3, and the beam splitter 3 is located between the collimating objective lens 4 and the light source 2; the transparent object 700 to be measured is placed between the collimating objective lens 4 and the plane target lens 5.

[0036] The transparent object 700 under test includes a first transmission plane 710, a second transmission plane 720, a third transmission plane 730, and a fourth transmission plane 740. The first and third transmission planes 710 are parallel to each other, as are the second and fourth transmission planes 720. The first transmission plane 710 is located on the vertical side near the collimating objective lens 4, and the third transmission plane 730 is located on the vertical side away from the collimating objective lens 4. The second transmission plane 720 is located on the side away from the light source 2, and the fourth transmission plane 740 is located on the side near the light source 2.

[0037] The light emitted from light source 2 passes through beam splitter prism 3 and collimating objective lens 4, exiting as a collimated beam. This collimated beam enters through the fourth transmission plane 740 of the transparent object 700 under test. After total internal reflection at a certain angle on the second transmission plane 720 inside the transparent object 700, it exits through the fourth transmission plane 740, undergoes specular reflection perpendicular to the surface of the target mirror 5, and then re-enters the fourth transmission plane 740 of the transparent object 700. After total internal reflection at a certain angle on the second transmission surface 720 of the transparent object 700, it returns through the fourth transmission plane 740. The returning collimated beam converges after passing through collimating objective lens 4, is reflected by beam splitter prism 3, and is then focused on the surface of photodetector 6. The incident plane and the exit plane of the beam are the same plane.

[0038] When the transparent object 700 being measured does not deflect, the beam returns and focuses on the photodetector 6 at the following position: Point. Photodetector 6 is a one-dimensional photodetector. The deflection angle of the transparent object 700 relative to the zero position is... When the beam returns, it is relatively at the focusing position of photodetector 6. The distance between the points is ,but , With collimating objective lens 4 focal length The following relationship exists between them:

[0039] in, This is a constant. Using this formula, the angle and orientation of the transparent object being measured can be calculated based on the detection results of the photodetector.

[0040] Fourth embodiment Combination Figure 5 This invention proposes an embodiment of a transparent object angle and attitude measurement device. A light source 2, a beam splitter 3, a collimating objective lens 4, and a plane target lens 5 are all fixed on a base 1. The light source 2 is placed on one side of the beam splitter 3, and the photodetector 6, collimating objective lens 4, and plane target lens 5 are located on the other side of the beam splitter 3; the photodetector 6 and the light source 2 are symmetrically placed about the beam splitter 3; the collimating objective lens 4 is located between the plane target lens 5 and the beam splitter 3, and the beam splitter 3 is located between the collimating objective lens 4 and the light source 2; the transparent object 700 to be measured is placed between the collimating objective lens 4 and the plane target lens 5.

[0041] The transparent object 700 under test includes a first transmission plane 710, a second transmission plane 720, a third transmission plane 730, and a fourth transmission plane 740. The first and third transmission planes 710 are parallel to each other, as are the second and fourth transmission planes 720. The first transmission plane 710 is located on the vertical side near the collimating objective lens 4, and the third transmission plane 730 is located on the vertical side away from the collimating objective lens 4. The second transmission plane 720 is located on the side away from the light source 2, and the fourth transmission plane 740 is located on the side near the light source 2.

[0042] The light emitted from the light source 2 passes through the beam splitter prism 3 and the collimating objective lens 4, and exits in the form of a collimated beam. The collimated beam is incident on the fourth transmission plane 740 of the transparent object 700 being tested. After undergoing multiple total internal reflections between the second transmission plane 720 and the fourth transmission plane 740 inside the transparent object 700 at a certain incident angle, it exits from the third transmission plane 730. After being perpendicular to the surface of the incident plane target mirror 5 and undergoing specular reflection, it re-enters the third transmission plane 730 of the transparent object 700 being tested. After undergoing multiple total internal reflections again at a certain incident angle between the surfaces of the second transmission plane 720 and the fourth transmission plane 740 inside the transparent object 700 being tested, it returns from the fourth transmission plane 740. The returning collimated beam is converged after passing through the collimating objective lens 4, and after being reflected by the beam splitter prism 3, it is focused on the surface of the photodetector 6.

[0043] When the transparent object 700 being measured does not deflect, the beam returns and focuses on the photodetector 6 at the following position: Point. Photodetector 6 is a one-dimensional photodetector. The deflection angle of the transparent object 700 relative to the zero position is... When the beam returns, it is relatively at the focusing position of photodetector 6. The distance between the points is ,but , With collimating objective lens 4 focal length The following relationship exists between them:

[0044] in, This is a constant. Using this formula, the angle and orientation of the transparent object being measured can be calculated based on the detection results of the photodetector.

[0045] Fifth Embodiment Figure 6 This demonstrates a scenario where the orientation of a transparent object at a 700° angle is measured using total internal reflection. The light source 2, beam splitter 3, collimating objective lens 4, and plane target lens 5 are all fixed to the base 1. The light source 2 is placed on one side of the beam splitter 3, while the photodetector 6, collimating objective lens 4, and plane target lens 5 are located on the other side. The photodetector 6 and the light source 2 are symmetrically placed about the beam splitter 3. The collimating objective lens 4 is located between the plane target lens 5 and the beam splitter 3, and the beam splitter 3 is located between the collimating objective lens 4 and the light source 2. The transparent object 700 being measured is placed between the collimating objective lens 4 and the plane target lens 5.

[0046] The transparent object 700 under test includes a first transmission plane 710, a second transmission plane 720, a third transmission plane 730, and a fourth transmission plane 740. The first and third transmission planes 710 are parallel to each other, as are the second and fourth transmission planes 720. The first transmission plane 710 is located on the vertical side near the collimating objective lens 4, and the third transmission plane 730 is located on the vertical side away from the collimating objective lens 4. The second transmission plane 720 is located on the side away from the light source 2, and the fourth transmission plane 740 is located on the side near the light source 2.

[0047] The light emitted from the light source 2 passes through the beam splitter prism 3 and the collimating objective lens 4, and then exits in the form of a collimated beam. The collimated beam is incident on the surface of the fourth transmission plane 740 of the transparent object 700 at a certain incident angle. After total external reflection, it is perpendicular to the surface of the target mirror 5 and undergoes specular reflection before being incident on the transparent object 700 again. After total external reflection on the surface of the fourth transmission plane 740 of the transparent object 700 at a certain incident angle, it returns. The returning collimated beam is converged after passing through the collimating objective lens 4, and after being reflected by the beam splitter prism 3, it is focused on the surface of the photodetector 6.

[0048] When the transparent object 700 being measured does not deflect, the beam returns and focuses on the photodetector 6 at the following position: Point. Photodetector 6 is a one-dimensional photodetector. The deflection angle of the transparent object 700 relative to the zero position is... When the beam returns, it is relatively at the focusing position of photodetector 6. The distance between the points is ,but , With collimating objective lens 4 focal length The following relationship exists between them:

[0049] in, This is a constant. Using this formula, the angle and orientation of the transparent object being measured can be calculated based on the detection results of the photodetector.

[0050] The embodiments described above are merely illustrative of implementation methods of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. A method for measuring the angle and attitude of a transparent object based on internal reflection, characterized in that: There is a difference in refractive index on both sides of the surface of the transparent object being tested. The light beam is incident from the side of the optically dense medium, undergoes total internal reflection on the surface of the transparent object being tested, and then exits to the plane target mirror. After specular reflection on the surface of the plane target mirror, it is incident on the surface of the transparent object being tested again. After total internal reflection on the surface of the transparent object being tested, the angle between the optical axis of the measuring beam and the original optical axis can be used to calculate the angle and attitude of the transparent object being tested.

2. The method for measuring the angle and attitude of a transparent object according to claim 1, characterized in that, The light beam remains collimated during transmission.

3. The method for measuring the angle and attitude of a transparent object according to claim 1, characterized in that, The light beam occurs on the surface of the transparent object being measured. Secondary total internal reflection .

4. The method for measuring the angle and attitude of a transparent object according to claim 1, characterized in that, When the transparent object being measured is in a specific angular orientation, the normal vector of the plane target mirror is perpendicular to the wavefront of its incident light beam. After specular reflection on the surface of the plane target mirror, the light beam returns along its original path, making an angle with the original optical axis. The zero position is defined as the angle and orientation of the transparent object being measured.

5. A device for measuring the angle and attitude of a transparent object, characterized in that, The device includes a base, a light source, a beam splitter prism, a collimating objective lens, a photodetector, and a plane target mirror. The light source, beam splitter prism, collimating objective lens, photodetector, and plane target mirror are fixed on the base. The light source is placed on one side of the beam splitter prism's beam splitting surface, and the photodetector, collimating objective lens, and plane target mirror are located on the other side of the beam splitter prism's beam splitting surface. The photodetector and the light source are placed symmetrically about the beam splitter prism's beam splitting surface. The transparent object being measured is located between the plane target mirror and the collimating objective lens, the collimating objective lens is located between the plane target mirror and the beam splitter prism, and the beam splitter prism is located between the collimating objective lens and the light source.

6. The transparent object angle and attitude measuring device according to claim 5, characterized in that, The light emitted from the light source passes through a beam splitter and then enters the collimating objective lens, exiting as a collimated beam. The collimated beam enters the surface of the transparent object being measured from the optically denser medium side, undergoes total internal reflection on the surface of the transparent object, and then enters the plane target mirror. After specular reflection on the surface of the plane target mirror, it enters the surface of the transparent object being measured again, undergoes total internal reflection on the surface of the transparent object being measured, and returns to the collimating objective lens. The collimated beam converges after passing through the collimating objective lens. This converged beam is then focused and imaged on the surface of the photodetector after passing through a beam splitter. The imaging result is transmitted to a computer, and the angle and attitude information of the transparent object being measured can be calculated through image processing algorithms.

7. The transparent object angle and attitude measuring device according to claim 5, characterized in that, The light emitted by the light source is emitted after passing through the fiber core, or after passing through the fiber core and the aperture. The types of apertures include pinhole apertures, slit apertures, and polygonal apertures.

8. The transparent object angle and attitude measuring device according to claim 5, characterized in that, A beam splitter can be a regular beam splitter, a polarizing beam splitter, or an anti-polarizing beam splitter.

9. The transparent object angle and attitude measuring device according to claim 5, characterized in that, Photodetectors can be one-dimensional or two-dimensional.

10. The transparent object angle and attitude measuring device according to claim 5, characterized in that, When the normal vector of the planar target mirror is perpendicular to the wavefront of the beam, the position where the beam focuses on the photodetector after returning is: point, The angle and orientation of the transparent object being measured at the point is defined as the zero position.

11. The transparent object angle and attitude measuring device according to claim 10, characterized in that, If a one-dimensional photodetector is used, the deflection angle of the transparent object being measured relative to the zero position is: At that time, the beam returns to the collimator and the focusing position deviates from the photodetector. The distance between the points is ,but , focal length of collimating objective lens The following relationship exists between them: in, It is a constant.

12. The transparent object angle and attitude measuring device according to claim 10, characterized in that, If a two-dimensional photodetector is used, when the transparent object being measured has a pitch angle or a yaw angle relative to the zero position, the focusing position of the two-dimensional photodetector will deviate. Distance between points The projection is onto two orthogonal directions; The pitch angle of the transparent object being measured relative to the zero position is: At that time, the beam returns to the collimator and the focusing position deviates from the photodetector. The distance of the point is projected in the corresponding direction as ; The yaw angle of the transparent object being measured relative to the zero position is: At that time, the beam returns to the collimator and the focusing position deviates from the photodetector. The distance of the point is projected in the corresponding direction as ; , and , focal length of collimating objective lens The following relationship exists between them: in, It is a constant.

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