Included angle detection and correction method and device for multiple emergent beams of prism structure

Abstract

The invention relates to the technical field of optical part manufacturing, and provides an included angle detection and correction method and device for multiple emergent beams of a prism structure. The detection correction method comprises the following steps: emitting a detection light beam towards a prism structure, and obtaining at least two beams of to-be-detected light emitted from the prism structure; and based on a laser interference principle, performing laser interference on the at least two beams of to-be-measured light to obtain a light beam included angle between the at least two beams of to-be-measured light. According to the technical scheme, the detection accuracy of the light beam included angle can be improved, and the technical problem that in the prior art, the detection accuracy of the light beam included angle is not high is solved.

Description

Technical Field

[0001] The present disclosure relates to the technical field of optical component manufacturing, and in particular to a method and device for detecting and correcting the angle of multiple outgoing light beams of a prism structure. Background Art

[0002] In an optical system, the predetermined optical path is usually designed as a theoretical optical path. In the theoretical optical path, the light beam is reflected, refracted, etc. without deviation, so that an ideal output light beam can be obtained. However, in the process of forming the theoretical optical path with actual optical elements, due to factors such as the processing error of the optical elements, deviations occur in the actual optical path. For example, a comprehensive deflection angle will be generated in the optical path, so that the output light beam itself will have a beam deflection angle, and a beam angle will be generated between multiple output light beams that are theoretically emitted in parallel.

[0003] The beam deflection angle refers to the change in the propagation direction of a beam of light due to reflection and refraction during its propagation. For example, a beam of light incident from one facet of a prism is refracted twice and then emitted from another facet of the prism. The deflection angle between the incident direction and the emitted direction of the light is the deflection angle of the light after passing through the prism.

[0004] The beam angle refers to the change in the propagation direction of multiple beams of light due to reflection and refraction from different optical components or different positions of the same optical component during the propagation process. For example, multiple beams of light incident from one facet of a prism are refracted twice and then emitted from the other facet of the prism. The angle between the multiple beams of light is the beam angle.

[0005] The beam angle of a glued prism is an important indicator for testing the performance of a glued prism. Usually, a collimator or a comparator can be used to detect the beam angle. The detection accuracy of a collimator is low, and it cannot eliminate the influence of other stray light in the detection system on the detection process, which has limitations for the detection of high-precision parts. Comparator detection also has low accuracy, and it cannot directly detect the beam angle between multiple beams of light. In addition, the use of a comparator to detect the beam angle requires a reference surface as a reference, and the introduction of a reference surface will bring systematic errors to the detection system.

[0006] How to improve the detection accuracy of the beam angle of the glued prism is a technical problem that needs to be solved urgently. Summary of the invention

[0007] In view of this, the embodiments of the present disclosure provide a method and device for detecting and correcting the angle of multiple light beams emitted from a prism structure, so as to solve the technical problem of low detection accuracy of the light beam angle in the prior art.

[0008] On the one hand, the present application provides a method for detecting and correcting the angle of multiple outgoing light beams of a prism structure, comprising the steps of: emitting a detection light beam toward the prism structure to obtain at least two outgoing light beams to be measured that are emitted from the prism structure;

[0009] Based on the principle of laser interference, laser interference is performed on at least two beams of emitted light to be measured to obtain a beam angle between the at least two beams of emitted light to be measured.

[0010] In an optional embodiment, based on the principle of laser interference, laser interference is performed on at least two beams of emitted light to be measured respectively, and the step of obtaining the beam angle between the at least two beams of emitted light to be measured includes:

[0011] Performing laser interference on at least two beams of emitted light to be measured respectively to obtain at least two corresponding interference surface figures;

[0012] According to the two interference surface diagrams, the beam angle between the two beams of emitted light to be measured is obtained.

[0013] In an optional embodiment, in the step of obtaining the beam angle between two beams of emitted light to be measured according to at least two interference surface patterns:

[0014] According to the two interference surface figures, the beam deflection angle of each beam of emitted light to be measured is calculated respectively;

[0015] The beam angle between the two beams of emitted light to be measured is calculated according to the beam deflection angles of the two beams of emitted light to be measured.

[0016] In an optional embodiment, based on the principle of laser interference, laser interference is performed on at least two beams of emitted light to be measured respectively, and after the step of obtaining the beam angle between the at least two beams of emitted light to be measured, the step further includes:

[0017] Calculate the optical path difference between the optical paths of the two beams of light to be measured according to the angle and deflection direction of the beam angle between the two beams of light to be measured;

[0018] According to the optical path difference between the optical paths of the two beams of measured outgoing light, the angle value and direction of the comprehensive deflection angle generated by all reflection processes in the optical path of the prism structure are obtained;

[0019] The angle of the reflecting surface in the prism structure is adjusted according to the angle value and direction of the comprehensive deflection angle, so that the beam angle between the two beams of emitted light to be measured is smaller than a preset angle value.

[0020] In an optional embodiment, in the step of adjusting the angle of the reflecting surface in the prism structure according to the angle value and direction of the comprehensive deflection angle so that the beam angle between the two beams of emitted light to be measured is less than a preset angle value:

[0021] The prism structure includes a common part and a single-use part for reflecting the light beam, wherein the common part is shared by the light paths of at least two light beams, and the single-use part is used exclusively in the light path of each laser beam;

[0022] By correcting the reflection angle of the single-use part in the optical path of the corresponding output light to be measured, the beam angle between the two beams of output light to be measured is made smaller than the preset angle value; wherein the direction of the angle corrected by the single-use part is opposite to the direction of the comprehensive deflection angle to offset the angular deviation of the comprehensive deflection angle.

[0023] In an optional embodiment, in the step of emitting a detection light beam toward a prism structure and acquiring at least two beams of to-be-detected light emitted from the prism structure:

[0024] The prism structure includes:

[0025] A beam splitter lens assembly, the beam splitter lens assembly is used to split a beam of detection laser, thereby emitting multiple beams of first emitted light, wherein one beam of detection laser is used as a detection beam, and the first emitted light is used as an emitted light to be measured;

[0026] or / and

[0027] A glued lens group forms multiple second output lights by propagating multiple detection input light beams along a predetermined optical path at different positions in the glued lens group and then outputting them separately; wherein the multiple detection input light beams are detection light beams, and the second output lights corresponding to the multiple detection input light beams are output lights to be measured.

[0028] In an optional embodiment, in the step of emitting a detection light beam toward a prism structure and acquiring at least two beams of to-be-detected light emitted from the prism structure:

[0029] The cemented prism comprises: a beam splitter lens group and a cemented lens group, wherein a plurality of first emitted light beams emitted from the beam splitter lens group serve as a plurality of detection incident light beams of the cemented lens group;

[0030] A beam of detection laser is split by a beam splitter lens group to form multiple beams of first outgoing light;

[0031] The multiple first emergent light beams propagate along a predetermined light path at different positions in the cemented lens assembly and then emerge respectively to form multiple second emergent light beams.

[0032] In an optional embodiment, in the step of correcting the reflection angle of the single-use portion in the optical path of the corresponding outgoing light to be measured so that the beam angle between the two outgoing lights to be measured is less than a preset angle value:

[0033] Beam splitter optics include:

[0034] A first polarization beam splitter prism, the first polarization beam splitter prism having a first light incident surface and a first polarization beam splitting surface;

[0035] At least one second prism, the second prism is connected to the first polarization beam splitter prism and has a first beam splitting surface, a second beam splitting surface and a first light emitting surface;

[0036] A third prism, the third prism is connected to the first light splitting surface of the second prism and has a third light splitting surface and a second light emitting surface, and the second light emitting surface is arranged on the same side as the first light emitting surface;

[0037] The detection laser is incident from the first light incident surface and is reflected by the first polarization splitting surface and then split by the first splitting surface to form two light beams, one of which penetrates the first splitting surface and enters the third prism and is reflected by the third splitting surface and then emitted from the second light emitting surface to form a first emitted light beam; the other light beam is reflected by the first splitting surface and then reflected by the second splitting surface and then emitted from the first light emitting surface to form another first emitted light beam;

[0038] The single-use portion includes a second beam splitting surface and / or a third beam splitting surface, and the angle of the beams between the first emergent lights is made smaller than a preset angle value by performing angle correction on the second beam splitting surface and / or the third beam splitting surface.

[0039] In an optional embodiment, in the step of correcting the reflection angle of the single-use portion in the optical path of the corresponding outgoing light to be measured so that the beam angle between the two outgoing lights to be measured is less than a preset angle value:

[0040] The glued lens set includes:

[0041] A second polarization beam splitter prism, the second polarization beam splitter prism having a second light input and output surface, a second polarization beam splitting surface, and a first side surface and a second side surface that are oppositely disposed;

[0042] At least two reflection combination mirrors, which are respectively arranged at different positions of the second polarization beam splitter prism and respectively arranged corresponding to different first emergent lights, wherein the reflection combination mirrors include a reflection wave plate and a corner cone, and the reflection wave plate and the corner cone are respectively arranged on the first side surface and the second side surface;

[0043] The first outgoing light enters the second polarization splitting prism through the second light input and output surface, is reflected by the second polarization splitting surface to the reflection wave plate, passes through the second polarization splitting surface after being reflected by the reflection wave plate and enters the angle cone, enters the second polarization splitting surface after being reflected on both sides by the angle cone and enters the reflection wave plate, enters the second polarization splitting prism after being reflected by the reflection wave plate and is reflected by the second polarization splitting surface, and is emitted from the second light input and output surface to form the second outgoing light;

[0044] The single-use portion includes a reflection surface of a reflection wave plate and / or a reflection surface of a corner cone, and the reflection surface of the reflection wave plate and / or the reflection surface of the corner cone is angle-corrected so that the beam angle between the second emergent lights is smaller than a preset angle value.

[0045] On the other hand, the present application also proposes a device for detecting the angle of a glued prism light beam, wherein the angle detection and correction method as described above is applied, and the detection device includes: a laser interferometer and a data processor, wherein the laser interferometer emits a detection beam toward the prism structure, obtains at least two beams of light to be measured emitted from the prism structure and performs laser interference on each of them; and the data processor performs calculations to obtain the beam angle between the at least two beams of light to be measured.

[0046] Compared with the prior art, the beneficial effects of the embodiments of the present disclosure are as follows: the technical solution of the present application uses laser interference to obtain interference data of reflected light and outgoing light when light enters a prism structure, and obtains the light beam angle between the two outgoing light beams based on the interference data, thereby realizing direct detection of the outgoing light beam angle between the two outgoing light beams of the glued prism, and the detection accuracy is high, so as to facilitate more precise adjustment of the outgoing light beam angle. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0048] Figure 1 is a schematic structural diagram of a glued prism provided in this embodiment;

[0049] Figure 2 is a structural schematic diagram of a cemented prism provided by this embodiment from another viewing angle;

[0050] Figure 3 is a top view of a cemented prism provided in this embodiment;

[0051] Figure 4 is a front view of a cemented prism provided in this embodiment;

[0052] Figure 5 This is a light path diagram of beam splitting performed by a beam splitter lens assembly of a cemented prism provided in this embodiment;

[0053] Figure 6 This is a light path diagram of a light beam of a glued lens assembly of a glued prism provided in this embodiment;

[0054] Figure 7 It is a flow chart of the main steps of a method for detecting and correcting the angle of multiple light beams emitted from a prism structure provided by this embodiment;

[0055] Figure 8 It is a flowchart diagram of detailed steps of a method for detecting and correcting the angle of multiple outgoing light beams of a prism structure provided in this embodiment.

[0056] Among them, the reference numerals in the figure are:

[0057] 100, beam splitter lens group; 110, first polarization beam splitter prism; 111, first light incident surface; 112, first polarization beam splitter surface; 120, second prism; 121, first beam splitter surface; 122, first light exit surface; 123, second beam splitter surface; 130, third prism; 131, third beam splitter surface; 132, second light exit surface; 200, glued lens group; 210, second polarization beam splitter prism; 211, second light incident and exit surface; 212, second polarization beam splitter surface; 213, first side surface; 214, second side surface; 220, reflection combination mirror; 221, reflection wave plate; 222, corner cone. DETAILED DESCRIPTION

[0058] In the following description, specific details such as specific system structures and technologies are provided for the purpose of illustration rather than limitation, so as to provide a thorough understanding of the embodiments of the present disclosure. However, it should be clear to those skilled in the art that the present disclosure may be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to avoid obstructing the description of the present disclosure with unnecessary details.

[0059] The following are explanations of the terms involved in the embodiments of the present disclosure:

[0060] Laser interferometer: A high-precision optical measuring instrument that uses the principle of laser interference to measure the shape and quality of an object's surface. The basic principle of laser interferometer is to split the laser into two beams, one as a reference beam, and the other beam is shot onto the surface of the object to be measured. After reflection, it meets the reference light again to form interference fringes. The shape and density of the interference fringes are related to the shape and surface quality of the surface of the object to be measured. Laser interferometer can be used to measure a variety of geometric accuracies such as straightness, verticality, angle, surface shape, parallelism, etc. The measurement accuracy of laser interferometer is very high, reaching the sub-micron level.

[0061] Glued prism: The glued prism in the embodiment of the present disclosure can be a complex optical component bonded by the photosensitive adhesive method. Since there is no medium between the bonding surfaces of the individual pieces of the glued prism, the optical performance remains unchanged. Compared with glue layer bonding, the glued prism bonded by the photosensitive adhesive method has higher mechanical strength and stable performance that can be maintained for decades; it also has small deformation and good cold and heat resistance. Parts whose surfaces will deform during bonding, parts that will debond due to their large dimensions, parts that work under high or low temperature conditions, or parts that work in the short-wave part of optical harmonics can be bonded by a special photosensitive adhesive method. However, the photosensitive adhesive process requires a very high manufacturing precision of the photosensitive adhesive surface.

[0062] Beam splitter: The beam splitter in the embodiment of the present disclosure is a beam splitter lens assembly, which is a glued assembly formed by multiple beam splitter prisms. After passing through the assembly, a light beam is split into multiple beams of light. Among them, the beam splitter prism is an optical prism that can split a light beam into two. Usually, a beam splitter film is coated on the surface of the optical prism, so that a beam of incident light is partially transmitted and partially reflected after passing through the coated surface, forming two beams of transmitted light and reflected light with a certain deflection angle.

[0063] Outgoing beam angle: During the propagation process, the propagation direction of light changes due to reflection and refraction. The deflection angle between the outgoing direction and the incident direction is called the beam angle. A beam of light incident from one facet of a prism is refracted twice and then emitted from another facet of the prism. The deflection angle between the outgoing direction and the incident direction of the light is the beam angle after the light passes through the prism. In the disclosed embodiment, the outgoing beam angle refers to the deflection angle between the outgoing directions of the two outgoing light beams after the light beam enters the glued prism and is split by the beam splitter of the glued prism.

[0064] The purpose of the present invention is to simplify the measurement of the light beam angle of the prism structure, improve the operability of the light beam deflection angle measurement, and can directly measure the angle between multiple beams of outgoing light from the glued prism, thereby improving the detection accuracy and reducing the difficulty of measuring the angle between multiple beams of outgoing light from the glued prism. The glued prism involved in the present invention is made of thirteen single pieces of optical glue. A beam of incident light passes through a beam splitter prism to form three beams of outgoing light. Each beam of outgoing light must be refracted by multiple single pieces. Ultimately, the parallelism between the three beams of outgoing light is required to be less than 15", so the single angle error of each single piece must be within 5", otherwise the angle error will be superimposed by the single piece error in the system and it will be difficult to achieve the index requirements. By detecting the angle between the outgoing light, the optical path of the glued prism with problems can be inferred, thereby correcting the unqualified glued single piece and achieving the standard deflection angle of the outgoing light beam of the entire optical path. Therefore, the following embodiments are proposed:

[0065] Embodiment 1

[0066] The present embodiment provides a method for detecting and correcting the angle of multiple light beams emitted from a prism structure. The light beam angle of the prism structure is detected. The prism structure may adopt a glued prism. The angle of the light beam of the glued prism is detected and corrected by the angle detection and correction method of the present embodiment, so as to improve the detection accuracy of the light beam angle of the glued prism and improve the product quality of the glued prism.

[0067] like Figure 1 , Figure 2 As shown, for the convenience of describing the present angle detection and correction method, a specific glued prism is used as an example for explanation. The glued prism mainly includes: a beam splitter lens group 100 or / and a glued lens group 200. The beam splitter lens group 100 is used to split a detection light beam. After the beam splitting, multiple beams of first output light are emitted from the beam splitter lens group 100. In theory, the multiple beams of first output light are flat light, but in fact, due to the existence of the comprehensive deflection angle of the internal structure of the prism, the multiple beams of first output light have a beam angle between each other. In order to avoid the beam angle affecting the final imaging effect, the beam angle needs to be detected and corrected, so as to obtain multiple beams of first output light (beam splitter 1, beam splitter 2 and beam splitter 3) that meet the preset angle (for example, the preset angle is 15″). The multiple beams of first output light formed in this way remain basically parallel, which can meet the requirements.

[0068] The glued lens group 200 is also composed of multiple prisms, which mainly provide a transmission path for multiple beams of flat light so that the multiple beams of light after splitting can propagate on a predetermined path. Therefore, it is also necessary to detect and correct the beam angle of the glued prism. The multiple beams of detected incident light propagate along the predetermined optical path at different positions in the glued lens group 200 and then are emitted separately to form multiple beams of second output light.

[0069] The beam splitter lens assembly 100 and the cemented lens assembly 200 can be used separately to detect and correct the beam angle, or they can be used in combination to detect and correct the beam angle. The specific method of detecting and correcting the beam angle will be explained in detail in the subsequent embodiments.

[0070] like Figure 1 , Figure 2As shown, further, in this embodiment, the beam splitter lens assembly 100 and the cemented lens assembly 200 are combined to form a cemented prism. The beam splitter lens assembly 100 is firstly fixed to the cemented lens assembly 200 after the beam angle is detected and corrected, and then the beam angle of the cemented lens assembly 200 is detected and corrected. Therefore, the multiple first output light beams emitted from the beam splitter lens group 100 serve as the multiple detection input light beams of the glued lens group 200, and the angle between any two of the multiple first output light beams is less than the preset angle value, and within the preset angle value, the parallelism of the two first output light beams is less than 15", which means they are almost parallel. Then, the multiple detection input light beams (first output light beams) of the glued lens group 200 also enter the glued lens group 200 in an almost parallel state, and the multiple almost parallel first output light beams are respectively emitted after propagating along a predetermined optical path at different positions in the glued lens group 200 to form multiple second output light beams. By performing beam angle detection and correction on the glued lens group 200, the angle between any two of the multiple second output light beams is less than the preset angle value, and the parallelism of the two second output light beams is less than 15", which means they are almost parallel.

[0071] like Figure 1 , Figure 2 , Figure 4 As shown, further, the specific structure of the beam splitter lens assembly 100 of this embodiment includes: a first polarization beam splitter prism 110, at least one second prism 120 and a third prism 130. The first polarization beam splitter prism 110 is composed of two triangular prisms, and the two connected inclined surfaces of the triangular prisms are coated with a beam splitting film to form a first polarization beam splitting surface 112, and the first polarization beam splitting surface 112 is set at a 45° inclination. The right-angled surface of the triangular prism facing the outside is the first light incident surface 111. The side where the first light incident surface 111 is located is the front side, and the first polarization beam splitting surface 112 reflects the incident light in the left and right directions as an example for structural description. The upper and lower sides of the second prism 120 are respectively set as inclined surfaces, and beam splitting films are respectively set to form the first beam splitting surface 121 and the second beam splitting surface 123. The right side surface of the second prism 120 is connected to the first polarization beam splitting prism 110, and the back of the second prism 120 is the first light emitting surface 122. The third prism 130 is connected to the first beam splitting surface 121 of the second prism 120, and has a third beam splitting surface 131 and a second light emitting surface 132, and the second light emitting surface 132 is arranged on the same side as the first light emitting surface 122; in the specific structure, the third prism 130 is connected to the left side of the second prism 120, the left and right sides of the third prism 130 are inclined and a beam splitting film is arranged on the inclined surface of the left side to form the third beam splitting surface 131, and the back side of the third prism 130 forms the second light emitting surface 132.

[0072] like Figure 1 , Figure 5As shown, the detection laser (incident light) is incident from the first light incident surface 111 and is reflected by the first polarization splitting surface 112 and then split by the first splitting surface 121 to form two light beams, one of which penetrates the first splitting surface 121 and enters the third prism 130, is reflected by the third splitting surface 131 and is emitted from the second light emitting surface 132 to form a first output light (splitting 1); the other light beam is reflected by the first splitting surface 121 and then reflected by the second splitting surface 123 and is emitted from the first light emitting surface 122 to form another first output light (splitting 2).

[0073] like Figure 1 , Figure 5 As shown, if a plurality of second prisms 120 are provided, the plurality of second prisms 120 are connected in sequence in the second direction, and the first light emitting surface 122 of each second prism 120 can emit a beam of first emitted light. For example, in the present embodiment, two second prisms 120 are provided, and the second second prism 120 is connected to the inclined surface where the second splitting surface 123 below the first second prism 120 is located. The light transmitted through the second splitting surface 123 enters the splitting surface below the second second prism 120, and is reflected by the splitting surface to the corresponding light emitting surface, forming a third beam of first emitted light (split 3).

[0074] It can be seen from the optical path that the prism structure includes multiple splitting surfaces and reflecting surfaces for reflecting the light beams. These splitting surfaces and reflecting surfaces are divided into a common part and a single-use part according to their functions in the optical path, wherein the common part is shared by at least two light beams, such as the first polarization splitting surface 112. The single-use part is used exclusively in the optical path of each laser light beam; for example, in the beam splitter lens assembly 100, the single-use part includes the second splitting surface 123 and / or the third splitting surface 131. When performing angle correction, the functions of the common part and the single-use part are different. The angle correction is performed on the common part of the two first outgoing lights, so that the self-deflection angles of the two first outgoing lights change synchronously. Since the self-deflection angles of the two lights change in the same amount, the beam angle between the two lights remains basically unchanged. When the angle correction is performed on the single-use part of a certain first outgoing light, the beam angle between the first outgoing light and other first outgoing lights is changed, thereby achieving the technical effect of this solution. Therefore, by performing angle correction on the second beam splitting surface 123 and / or the third beam splitting surface 131 , the beam angle between the emitted lights can be changed.

[0075] like Figure 1 , Figure 2 , Figure 3 , Figure 4As shown, further, the cemented lens assembly 200 of this embodiment specifically includes: a second polarization beam splitter prism 210 and at least two reflection combination lenses 220. The second polarization beam splitter prism 210 of this embodiment is arranged on the back of the beam splitter lens assembly 100, and has a second light input and output surface 211, a second polarization beam splitting surface 212, and a first side surface 213 and a second side surface 214 that are arranged opposite to each other. The side of the second polarization beam splitter prism 210 facing the beam splitter lens assembly 100 is the front side, the front side is the second light input and output surface 211, the second polarization beam splitting surface 212 is arranged at a 45° inclination, the first side surface 213 is the right side surface, and the second side surface 214 is the left side surface. The reflection combination mirrors 220 are respectively arranged at different positions of the second polarization splitter prism 210 and respectively arranged corresponding to different first emergent lights. Therefore, a plurality of reflection combination mirrors 220 are arranged corresponding to the number of first emergent lights, and are arranged in the up and down directions. According to the different positions of the first emergent lights emitted by the second prism 120 and the third prism 130, the placement of the reflection combination mirrors 220 at the corresponding positions is also different.

[0076] The reflection combination mirror 220 includes a reflection wave plate 221 and a corner cone 222, which are respectively arranged on the first side surface 213 and the second side surface 214. In the specific structure, since the first emitted light emitted from the third prism 130 and the first emitted light emitted from the plurality of second prisms 120 are staggered in the left-right direction, the two reflection cone surfaces of the corner cone 222 corresponding to the third prism 130 are located in the up-down direction, and the two reflection cone surfaces of the corner cone 222 in the plurality of reflection combination mirrors 220 corresponding to the plurality of second prisms 120 are located in the left-right direction.

[0077] like Figure 1 , Figure 2 , Figure 6 As shown, the first output light enters the second polarization splitter prism 210 through the second light input and output surface 211, is reflected by the second polarization splitter surface 212 to the reflection wave plate 221, passes through the second polarization splitter surface 212 after being reflected by the reflection wave plate 221 and enters the angle cone 222, enters through the second polarization splitter surface 212 and enters the reflection wave plate 221 after being reflected on both sides by the angle cone 222, enters the second polarization splitter surface 212 after being reflected by the reflection wave plate 221, enters the second polarization splitter prism 210 after being reflected by the second polarization splitter surface 212, and is emitted from the second light input and output surface 211 to form the second output light.

[0078] Therefore, it can be seen from the optical path principle of the cemented lens assembly 200 that the single-use portion includes the reflection surface of the reflection wave plate 221 and / or the reflection surface of the corner cone 222, and the angle of the light beams between the second output lights is changed by performing angle correction on the reflection surface of the reflection wave plate 221 and / or the reflection surface of the corner cone 222.

[0079] This embodiment of the present application provides a method for detecting and correcting the angle of multiple light beams emitted from a prism structure, which is used to detect and correct the angle of the beams between the multiple light beams to be measured from the prism structure. The prism structure can be the beam splitter lens group or / and the glued prism structure of the glued lens group in the first embodiment.

[0080] like Figure 7 As shown, the angle detection and correction method mainly includes the following steps:

[0081] Step S100 , emitting a detection light beam toward a prism structure to obtain at least two beams of to-be-detected light emitted from the prism structure.

[0082] In a specific process, if the prism structure is the above-mentioned beam splitter lens group, the detection light beam is a detection laser beam, the multiple beams of emitted light to be measured are multiple beams of first emitted light, and the first emitted light is the emitted light to be measured.

[0083] If the prism structure is the above-mentioned cemented lens group, the detection beam is a plurality of detection incident beams, the output light to be measured is a plurality of second output light beams corresponding to the plurality of detection incident beams, and the output light to be measured is the second output light.

[0084] The structure is described by applying the angle detection correction method to a glued prism composed of a beam splitter lens group and a glued lens group. Then, after a beam of detection laser is split by the beam splitter lens group, multiple beams of first output light are formed, and the multiple beams of first output light serve as multiple beams of detection incident light beams of the glued lens group and enter the glued lens group to emit multiple beams of second output light.

[0085] Step S200: Based on the principle of laser interference, laser interference is performed on at least two beams of emitted light to be measured to obtain a beam angle between the at least two beams of emitted light to be measured.

[0086] In the specific process, the laser interference principle is used and the beam angle between two beams of parallel light can be detected by calculation. The accuracy of parallelism detection using the laser interference principle can reach within 1", and mutual interference between multiple light beams can be avoided. The method of measuring parallelism using only the laser interference principle can directly detect the beam deflection angle between two beams of parallel outgoing light in the glued prism, which is simple and convenient.

[0087] Therefore, the above steps simplify the detection scheme of the light beam angle of the prism structure, improve the operability of the light beam angle detection between the measured outgoing lights, can directly measure the light beam angle between multiple outgoing light beams of the glued prism, improve the detection accuracy, and reduce the difficulty of detecting the angle between multiple outgoing light beams of the glued prism.

[0088] like Figure 7 , Figure 8As shown, further, the above step S200 specifically includes the following steps:

[0089] Step S210 , performing laser interference on at least two beams of emitted light to be measured to obtain at least two corresponding interference surface patterns.

[0090] Step S220: Obtain the beam angle between the two emitted light beams to be measured according to the two interference surface patterns.

[0091] In the specific process, the basic principle of laser interference is that part of the laser emitted by the laser transmitter is reflected back to the receiver when passing through the standard mirror to form a reference light, and part is transmitted and returns to the receiver after passing through the part to be measured. The two beams of light thus form interference fringes (interference surface diagram). The shape and density of the interference fringes (interference surface diagram) are related to the shape and surface quality of the surface of the object to be measured. The interference fringes (interference surface diagram) reflect the optical path difference after the light passes through the part, and the optical path difference is related to the angle of the part. Therefore, the deflection angle of the light passing through the part can be accurately detected through the principle of laser interference. The corresponding interference surface diagrams can be obtained by performing laser interference on different multiple beams of the outgoing light to be measured. According to the interference law of the two interference surface diagrams, the beam angle between the two beams of the outgoing light to be measured can be calculated.

[0092] like Figure 7 , Figure 8 As shown, further, the specific steps of step S220 include:

[0093] Step S221, calculating the beam deflection angle of each beam of emitted light to be measured according to the two interference surface diagrams.

[0094] Since laser interference is performed on each beam of emitted light to be measured separately, a plurality of corresponding interference surface diagrams are obtained. And each interference surface diagram can obtain the beam deflection angle of each beam of emitted light to be measured according to the law of interference and deflection angle.

[0095] Step S222: Calculate the beam angle between the two beams of light to be measured according to the beam deflection angles of the two beams of light to be measured.

[0096] When the beam deflection angles (angle value and direction) of the respective outgoing lights to be measured are detected, the beam angle between the two can be obtained directly through angle calculation.

[0097] According to the comparison between the beam angle and the preset angle value of the quality requirement, when the beam angle is less than the preset angle value, it is considered that the prism structure meets the quality requirement and no angle correction is required. When the beam angle is greater than or equal to the preset angle value, angle correction is required to make the beam angle of the outgoing light after passing through the prism structure less than the preset angle value, so that the prism structure meets the quality requirement.

[0098] like Figure 8 As shown, the specific steps of the angle correction process are as follows:

[0099] Step S300: Calculate the optical path difference between the optical paths of the two beams of emitted light to be measured according to the angle and deflection direction of the beam angle between the two beams of emitted light to be measured.

[0100] In the specific process, the angle and deflection direction of the light beam angle can be obtained according to the two interference surface diagrams. The light beam angle is caused by the difference between the reflection surface (beam splitting surface) of the optical single element in the optical path and the theoretical value. Therefore, the two beams of measured light obtained with the same optical path in theory have different actual optical paths due to the error of the actual optical single element. Therefore, according to the light beam angle obtained by detection, the optical path difference of the two beams of measured light in the optical path can be calculated.

[0101] Step S310: Obtain the angle value and direction of the comprehensive deflection angle generated by all reflection processes in the optical path of the prism structure according to the optical path difference between the optical paths of the two beams of emitted light to be measured.

[0102] In the specific process, there will be a certain deviation in the actual optical path of each light beam inside the prism structure. This deviation is reflected by an angle, namely a comprehensive deflection angle. For example, if the actual optical paths of each light beam are the same and the optical path difference is 0, then the comprehensive deflection angle is 0. However, due to the quality problem of the prism, the optical path difference exists, so that there is a comprehensive deflection angle between the light paths of the glued prism. The comprehensive deflection angle is compounded by the reflection angle deviation of each prism piece, so it can reflect the overall deviation between the light paths of the entire prism structure. The angle and deflection direction of the light beam angle between the two beams of light to be measured are obtained based on the results of the laser interference detection process, thereby obtaining the angle and direction of the comprehensive deflection angle of the entire light path. Usually, the comprehensive deflection angle is reflected by detecting the light beam angle between multiple beams of light to be measured.

[0103] Step S320: adjusting the angle of the reflecting surface in the prism structure according to the angle value and direction of the comprehensive deflection angle so that the beam angle between the two beams of emitted light to be measured is smaller than a preset angle value.

[0104] In the specific process, the angle of the prism can be adjusted according to the angle and direction of the comprehensive deflection angle of the entire optical path. For example, the angle of one or more reflective surfaces (reflective surfaces) in each prism can be adjusted. The beam angle between the two beams of light to be measured is made smaller than the preset angle value, so that the multiple beams of light to be measured are basically parallel. For example, the preset angle value range can be 10" to 20", for example, the preset angle can be 15".

[0105] This embodiment specifically corrects the reflection angle of the single-use portion in the optical path of the corresponding output light to be measured so that the light beam angle between the two beams of output light to be measured is smaller than a preset angle value; wherein the direction of the angle corrected by the single-use portion is opposite to the direction of the comprehensive deflection angle so as to offset the angular deviation of the comprehensive deflection angle.

[0106] Combined with the structure in the first embodiment, for example, in the present beam splitter lens assembly, the single-use part includes a second beam splitting surface and / or a third beam splitting surface. If multiple second prisms are used, the second beam splitting surfaces of the multiple second prisms are divided into single-use parts. For example, in the structure, by performing angle correction on the multiple second beam splitting surfaces, the emission angles of the first output light (beam splitting 2) at the bottom and the first output light (beam splitting 2) at the bottom can be adjusted. And by adjusting the angle of the third beam splitting surface, the first output light (beam splitting 1) at the top can be adjusted. After adjusting the comprehensive deflection angle of the beam splitter lens assembly respectively, it is finally required that the parallelism between the three beams of first output light emitted is less than 15″, so the single angle angle error of each single-use part must be within 5″.

[0107] For example, in the present glued lens group, the single-use part includes the reflection surface of the reflection wave plate and / or the reflection surface of the corner cone, and the angle of the light beams between the second output lights is changed by performing angle correction on the reflection surface of the reflection wave plate and / or the reflection surface of the corner cone. After adjusting the comprehensive deflection angle of the glued lens group respectively, the parallelism between the three second output lights emitted is finally required to be less than 15", so the single angle error of each single-use part must be within 5", otherwise the angle error will be superimposed by the single-piece error in the detection system and it is difficult to achieve the index requirements.

[0108] By detecting the beam angles between the two outgoing lights to be tested, it is possible to infer the optical path of the prism structure (glued prism) with problems, thereby correcting the unqualified prism units and ensuring that the beam angles of the outgoing lights emitted by the entire optical path meet the standards, thereby determining that the quality of the prism structure (glued prism) meets the standards.

[0109] Embodiment 2

[0110] The present application also proposes a device for detecting the angle of a glued prism light beam, wherein the angle detection and correction method as described above is applied, and the detection device includes: a laser interferometer and a data processor, wherein the laser interferometer emits a detection light beam toward the prism structure, obtains at least two beams of light to be measured emitted from the prism structure and performs laser interference on each of them; and the data processor performs calculations to obtain the beam angle between the at least two beams of light to be measured.

[0111] The laser interferometer can be used to detect the beam angle between multiple parallel beams of prism structure (cemented prism). The accuracy of parallelism detection by laser interferometer can reach within 1", and mutual interference between multiple light beams can be avoided. The beam angle between multiple parallel outgoing light beams of the cemented prism can be directly detected by only using the laser interferometer to measure parallelism, which is simple and convenient.

[0112] In summary, the present application provides a method and device for detecting and correcting the angle of multiple outgoing light beams of a prism structure. The laser interferometer can quickly and accurately measure the parallelism between the multiple outgoing light beams of the glued prism, and the laser interferometer can give the direction of deflection of the outgoing light beam, thereby obtaining the comprehensive deflection angle of the glued prism, so that the angle of the single prism can be controlled during the process of gluing the prism, and by changing the angle of the single prism, the angle correction can be complementary to offset the accumulation of errors in a beam path in which the single prism participates.

[0113] The above embodiments are only used to illustrate the technical solutions of the present disclosure, rather than to limit them. Although the present disclosure has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present disclosure, and should all be included in the protection scope of the present disclosure.

Claims

1. A method for detecting and correcting the angle of multiple light beams emitted from a prism structure, characterized in that: The angle detection and correction method comprises the steps of: Emitting a detection light beam toward the prism structure to obtain at least two beams of to-be-detected light emitted from the prism structure; Based on the principle of laser interference, laser interference is performed on at least two beams of the to-be-measured emergent light respectively to obtain a beam angle between the at least two beams of the to-be-measured emergent light.

2. The method for detecting and correcting the angle of multiple light beams emitted from a prism structure according to claim 1, characterized in that: Based on the principle of laser interference, the steps of performing laser interference on at least two beams of the to-be-measured emitted light respectively to obtain the beam angle between the at least two beams of the to-be-measured emitted light include: Performing laser interference on at least two beams of the emitted light to be measured respectively to obtain at least two corresponding interference surface figures; According to the two interference surface patterns, the beam angle between the two beams of the emitted light to be measured is obtained.

3. The method for detecting and correcting the angle of multiple light beams emitted from a prism structure according to claim 2, characterized in that: In the step of obtaining the beam angle between the two beams of the emitted light to be measured according to at least two of the interference surface patterns: According to the two interference surface diagrams, respectively calculating the beam deflection angle of each beam of the outgoing light to be measured; The beam angle between the two beams of the emitted light to be measured is calculated according to the beam deflection angles of the two beams of the emitted light to be measured.

4. The method for detecting and correcting the angle of multiple light beams emitted from a prism structure according to claim 1, characterized in that: Based on the principle of laser interference, laser interference is performed on at least two beams of the to-be-measured emitted light respectively, and after the step of obtaining the beam angle between the at least two beams of the to-be-measured emitted light, the step further includes: Calculating the optical path difference between the optical paths of the two beams of the outgoing light to be measured according to the angle and deflection direction of the beam angle between the two beams of the outgoing light to be measured; According to the optical path difference between the optical paths of the two beams of the outgoing light to be measured, the angle value and direction of the comprehensive deflection angle generated by all reflection processes in the optical path of the prism structure are obtained; The angle of the reflecting surface in the prism structure is adjusted according to the angle value and direction of the comprehensive deflection angle, so that the light beam angle between the two beams of the emitted light to be measured is smaller than a preset angle value.

5. The method for detecting and correcting the angle of multiple light beams emitted from a prism structure according to claim 4, characterized in that: In the step of adjusting the angle of the reflecting surface in the prism structure according to the angle value and direction of the comprehensive deflection angle so that the beam angle between the two beams of the emitted light to be measured is less than a preset angle value: The prism structure includes a common part and a single-use part for reflecting the light beam, wherein the common part is shared by the light paths of at least two light beams, and the single-use part is used exclusively in the light path of each laser beam; By correcting the reflection angle of the single-use portion in the optical path of the corresponding output light to be measured, the light beam angle between the two beams of the output light to be measured is made smaller than a preset angle value; wherein the direction of the angle corrected by the single-use portion is opposite to the direction of the comprehensive deflection angle to offset the angular deviation of the comprehensive deflection angle.

6. The method for detecting and correcting the angle of multiple light beams emitted from a prism structure according to claim 5, characterized in that: In the step of emitting a detection light beam toward the prism structure to obtain at least two beams of emitted light to be measured emitted from the prism structure: The prism structure includes: A beam splitter lens assembly, wherein the beam splitter lens assembly is used to split a beam of detection laser, thereby emitting multiple beams of first emitted light, wherein one beam of detection laser is used as a detection beam, and the first emitted light is used as an emitted light to be measured; or / and A glued lens group forms multiple second output lights by propagating multiple detection input light beams along a predetermined optical path at different positions in the glued lens group and then outputting them separately; wherein the multiple detection input light beams are detection light beams, and the second output lights corresponding to the multiple detection input light beams are output lights to be measured.

7. The method for detecting and correcting the angle of multiple light beams emitted from a prism structure according to claim 6, characterized in that: In the step of emitting a detection light beam toward the prism structure to obtain at least two beams of emitted light to be measured emitted from the prism structure: The beam splitter lens group and the glued lens group form a glued prism, and the multiple first output light beams emitted from the beam splitter lens group serve as the multiple detection input light beams of the glued lens group. After a detection laser beam is split by the beam splitter lens group, multiple first output light beams are formed; the multiple first output light beams propagate along a predetermined optical path at different positions in the glued lens group and are respectively emitted to form multiple second output light beams.

8. The method for detecting and correcting the angle of multiple light beams emitted from a prism structure according to claim 7, characterized in that: In the step of correcting the reflection angle of the single-use portion in the optical path of the corresponding outgoing light to be measured so that the beam angle between the two outgoing lights to be measured is less than a preset angle value: The beam splitter lens assembly comprises: A first polarization beam splitter prism, wherein the first polarization beam splitter prism has a first light incident surface and a first polarization beam splitting surface; at least one second prism, the second prism being connected to the first polarization beam splitting prism and having a first beam splitting surface, a second beam splitting surface and a first light emitting surface; A third prism, the third prism is connected to the first light splitting surface of the second prism and has a third light splitting surface and a second light emitting surface, and the second light emitting surface is arranged on the same side as the first light emitting surface; The detection laser is incident from the first light incident surface and is reflected by the first polarization splitting surface and then split by the first splitting surface to form two light beams, one of which penetrates the first splitting surface and enters the third prism, is reflected by the third splitting surface and is emitted from the second light emitting surface to form a beam of the first emitted light; the other light beam is reflected by the first splitting surface and then reflected by the second splitting surface and is emitted from the first light emitting surface to form another beam of the first emitted light; The single-use portion of the beam splitter lens assembly includes a second beam splitting surface and / or a third beam splitting surface, and the angle of the beams between the first emergent lights is made smaller than a preset angle value by performing angle correction on the second beam splitting surface and / or the third beam splitting surface.

9. The method for detecting and correcting the angle of multiple light beams emitted from a prism structure according to claim 7, characterized in that: In the step of correcting the reflection angle of the single-use portion in the optical path of the corresponding outgoing light to be measured so that the beam angle between the two outgoing lights to be measured is less than a preset angle value: The glued lens group comprises: A second polarization beam splitter prism, the second polarization beam splitter prism having a second light input and output surface, a second polarization beam splitting surface, and a first side surface and a second side surface that are opposite to each other; at least two reflection combination mirrors, which are respectively arranged at different positions of the second polarization beam splitter prism and respectively arranged corresponding to different first emergent lights, wherein the reflection combination mirror comprises a reflection wave plate and a pyramid, and the reflection wave plate and the pyramid are respectively arranged on a first side surface and a second side surface; The first outgoing light enters the second polarization beam splitter prism through the second light input and output surface, is reflected by the second polarization beam splitter surface to the reflection wave plate, passes through the second polarization beam splitter surface after being reflected by the reflection wave plate and enters the angle cone, enters the reflection wave plate after being reflected on both sides by the angle cone, passes through the second polarization beam splitter surface and enters the reflection wave plate, enters the second polarization beam splitter prism after being reflected by the reflection wave plate, is reflected by the second polarization beam splitter surface, and is emitted from the second light input and output surface to form the second outgoing light; Wherein, the single-use part of the cemented lens assembly includes a reflection surface of a reflection wave plate and / or a reflection surface of a corner cone, and the reflection surface of the reflection wave plate and / or the reflection surface of the corner cone is angle-corrected so that the beam angle between the second emergent lights is smaller than a preset angle value.

10. A device for detecting the angle of a light beam of a cemented prism, characterized in that: The angle detection and correction method as described in any one of claims 1 to 9 is applied, and the detection device includes: a laser interferometer and a data processor, wherein the laser interferometer emits a detection light beam toward the prism structure, obtains at least two beams of light to be measured emitted from the prism structure and performs laser interference on each of them; and the data processor performs calculation to obtain the beam angle between the at least two beams of light to be measured.

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