Bidirectional alignment measuring and calibrating device and method and bidirectional alignment equipment

Abstract

The invention provides a bidirectional alignment measuring and calibrating device, a bidirectional alignment measuring and calibrating method and bidirectional alignment equipment. When a first included angle is formed between a first spectral confocal system and an optical symmetry axis, the first spectral confocal system translates a fixed distance along the optical symmetry axis for the first time relative to a marking plate; obtaining the distance difference between the first distance and the second distance corresponding to the distance measurement of the first spectral confocal system before and after the first translation; after the marking plate is rotated by a set angle around a first vertical direction such as a z axis, the first spectral confocal system is translated by a fixed distance for the second time along the optical symmetry axis relative to the marking plate, and the distance difference between a third distance and a fourth distance corresponding to distance measurement of the first spectral confocal system before and after the second translation is obtained; according to the first sine relation and the second sine relation of the two translations, a first included angle and the like are solved, the coaxiality of the bidirectional spectrum confocal system is finally achieved, meanwhile, the working distance overlapping of the bidirectional imaging alignment system and the bidirectional spectrum confocal system is measured and calibrated, and the reliability is improved.

Description

Technical Field

[0001] The present application relates to the field of precision machining technology, and in particular to a bidirectional alignment calibration device, method and bidirectional alignment equipment. Background Art

[0002] With the development of standardization and industrialization of processing and assembly in the manufacturing process, the precise alignment between components requires the assistance of various measuring sensors. In many applications, there is a wide demand for six-axis (such as X, Y, Z, RX, RY, RZ) bidirectional alignment devices between components, such as the assembly of precision devices, the adjustment of optical components, and precision control equipment in the semiconductor industry. The calibration accuracy of the bidirectional alignment device determines the alignment accuracy of the equipment control components. Therefore, it is particularly important to achieve high-precision calibration of the bidirectional alignment device.

[0003] The bidirectional alignment device is usually equipped with a dual-spectral confocal system for leveling, and a dual-image recognition alignment system for horizontal and vertical rotation alignment. Although the traditional bidirectional alignment device can achieve leveling and alignment, when the measured plate is tilted, the calibrated bidirectional spectral confocal system is also tilted, resulting in complex and inconvenient adjustment. If it needs to be found through continuous adjustment, the measurement and calibration process is cumbersome because there is no clear adjustment direction and adjustment amount.

[0004] Therefore, a bidirectional alignment device and a solution for calibrating the same are needed. Summary of the invention

[0005] In view of this, the embodiments of the present specification provide a bidirectional alignment calibration device, method and bidirectional alignment equipment.

[0006] The embodiments of this specification provide the following technical solutions:

[0007] The embodiment of this specification provides a bidirectional alignment measurement and calibration device, including:

[0008] A first spectral confocal system, a second spectral confocal system, a first imaging alignment system, a second imaging alignment system, a marking plate, a detector and a bidirectional alignment module;

[0009] The first spectral confocal system and the second spectral confocal system are respectively arranged on two sides of the bidirectional alignment module;

[0010] The first imaging alignment system and the second imaging alignment system are respectively spaced apart from the first spectral confocal system by a preset distance along the optical symmetry axis direction of the bidirectional alignment module, and are also respectively arranged on both sides of the bidirectional alignment module;

[0011] The marking plate is arranged on at least one side of the bidirectional alignment module; the marking plate is provided with a coaxial alignment mark and a working distance alignment mark;

[0012] The first spectral confocal system and the optical symmetry axis form a first plane, and there is a first vertical direction perpendicular to the first plane;

[0013] The first vertical direction and the optical symmetry axis form a second plane, and there is a second vertical direction perpendicular to the second plane;

[0014] Wherein, when the first spectral confocal system forms a first angle with the direction of the optical symmetry axis, the first spectral confocal system is first translated by a fixed distance relative to the marking plate along the direction of the optical symmetry axis, and a first distance obtained by measuring the distance on the marking plate by the first spectral confocal system before the first translation and a second distance obtained by measuring the distance on the marking plate by the first spectral confocal system after the first translation are respectively obtained, and a difference between the first distance and the second distance is obtained;

[0015] A first sinusoidal relationship is formed according to the first angle, the second angle between the marking plate and the optical symmetry direction, the fixed distance, and the difference between the first distance and the second distance;

[0016] After the marking plate is rotated about a first vertical rotation to a set angle, the first spectral confocal system is secondarily translated by a fixed distance relative to the marking plate along the optical symmetry axis, and a third distance obtained by the first spectral confocal system on the marking plate before the second translation and a fourth distance obtained by the first spectral confocal system on the marking plate after the second translation are respectively obtained, and a difference between the third distance and the fourth distance is obtained;

[0017] A second sinusoidal relationship is formed according to the first angle, the second angle between the marking plate and the optical symmetry axis, the fixed distance, the set angle, and the difference between the third distance and the fourth distance;

[0018] According to the first sinusoidal relationship and the second sinusoidal relationship, a first angle is obtained between the first spectral confocal system and the direction of the optical symmetry axis, and a second angle is obtained between the marking plate and the direction of the optical symmetry axis, and the first spectral confocal system is adjusted to be perpendicular to the direction of the optical symmetry axis, and the marking plate is adjusted to be parallel to the direction of the optical symmetry axis;

[0019] Determine that the first spectral confocal system is perpendicular to the first vertical, and the marking plate is perpendicular to the first vertical; when the first spectral confocal system is parallel to the second vertical, and the marking plate is perpendicular to the second vertical, and the second spectral confocal system is parallel to the second vertical, respectively use the first spectral confocal system and the second spectral confocal system to image the coaxial alignment marks of the same size on the marking plate, and when it is measured that the distance between the first spectral confocal system and the marking plate is the same as the distance between the second spectral confocal system and the marking plate, and the spectral signal amplitudes are the same, the optical axes of the two spectral confocal systems are coaxial;

[0020] Keep the marking plate still, and make sure that the working distance of the first imaging alignment system and the working distance of the second imaging alignment system overlap with the working distances of the two-spectral confocal systems respectively.

[0021] The embodiment of this specification also provides a bidirectional alignment calibration method, including:

[0022] When the first spectral confocal system forms a first angle with the direction of the optical symmetry axis, the first spectral confocal system is first translated by a fixed distance relative to the marking plate along the direction of the optical symmetry axis, and a first distance obtained by the first spectral confocal system on the marking plate before the first translation and a second distance obtained by the first spectral confocal system on the marking plate after the first translation are respectively obtained, and a difference between the first distance and the second distance is obtained;

[0023] A first sinusoidal relationship is formed according to the first angle, the second angle between the marking plate and the optical symmetry axis, the fixed distance, and the difference between the first distance and the second distance;

[0024] After the marking plate is rotated about a first vertical rotation to a set angle, the first spectral confocal system is secondarily translated by a fixed distance relative to the marking plate along the optical symmetry axis, and a third distance obtained by the first spectral confocal system on the marking plate before the second translation and a fourth distance obtained by the first spectral confocal system on the marking plate after the second translation are respectively obtained, and a difference between the third distance and the fourth distance is obtained;

[0025] A second sinusoidal relationship is formed according to the first angle, the second angle between the marking plate and the optical symmetry axis, the fixed distance, the set angle, and the difference between the third distance and the fourth distance;

[0026] According to the first sinusoidal relationship and the second sinusoidal relationship, a first angle is obtained between the first spectral confocal system and the direction of the optical symmetry axis, and a second angle is obtained between the marking plate and the direction of the optical symmetry axis, and the first spectral confocal system is adjusted to be perpendicular to the direction of the optical symmetry axis, and the marking plate is adjusted to be parallel to the direction of the optical symmetry axis;

[0027] Determine that the first spectral confocal system is perpendicular to the first vertical and the marking plate is perpendicular to the first vertical; determine that the first spectral confocal system is parallel to the second vertical and the marking plate is perpendicular to the second vertical, and the second spectral confocal system is parallel to the second vertical, and when the marking plate is fixed, respectively use the first spectral confocal system and the second spectral confocal system to image the coaxial alignment marks of the same size on the marking plate, and when the distance between the first spectral confocal system and the marking plate is the same as the distance between the second spectral confocal system and the marking plate, and the spectral signal amplitudes are the same, the optical axes of the two spectral confocal systems are coaxial;

[0028] Keep the marking plate still, and make sure that the working distance of the first imaging alignment system and the working distance of the second imaging alignment system overlap with the working distances of the two-spectral confocal systems respectively.

[0029] Compared with the prior art, the beneficial effects that can be achieved by at least one of the above technical solutions adopted in the embodiments of this specification include at least:

[0030] This application obtains two corresponding first and second sinusoidal relationships respectively by translating a fixed distance when a spectral confocal system is at different angles to the direction of the optical symmetry axis, and solves the angles that can be obtained twice, that is, by quantifying the angle, the coaxiality of the two-way spectral confocal system in the two-way alignment device can be measured and calibrated, and the working distance overlap between the two-way imaging alignment system and the two-way spectral confocal system can be measured and calibrated, thereby improving the reliability of the alignment device. The constructed optical module can realize the online six-axis alignment function in the application scenario, which not only improves the alignment accuracy, but also improves the convenience of operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0032] Figure 1 This is a schematic diagram of the spectral confocal system and imaging alignment system provided in the embodiments of this specification. Figure 1 ;

[0033] Figure 2 It is a schematic diagram of measuring the tilt angle of the marking plate and the tilt angle of the spectral confocal system provided in the embodiments of this specification;

[0034] Figure 3 is a vertical schematic diagram of a spectral confocal system provided in an embodiment of this specification;

[0035] Figure 4 is a schematic diagram of the co-optical axis of a two-spectral confocal system provided in an embodiment of this specification;

[0036] Figure 5 It is a schematic diagram of the dual-spectrum confocal working distances overlapping but not on the same axis provided in the embodiments of this specification;

[0037] Figure 6 It is a schematic diagram of measuring and calibrating the overlapping working distances of the imaging alignment system and the spectral confocal system provided in the embodiments of this specification;

[0038] Figure 7 It is a schematic diagram of the measurement and calibration of the overlapping working distances of the dual imaging alignment system and the dual spectrum confocal system provided in the embodiments of this specification;

[0039] Figure 8 It is a schematic diagram of the double-marking plate calibration provided in the embodiment of this specification. DETAILED DESCRIPTION

[0040] The embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0041] The following describes the implementation methods of the present application through specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The present application can also be implemented or applied through other different specific implementation methods, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that, in the absence of conflict, the following embodiments and the features in the embodiments can be combined with each other. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work belong to the scope of protection of the present application.

[0042] It should be noted that various aspects of the embodiments within the scope of the appended claims are described below. It should be apparent that the aspects described herein can be embodied in a wide variety of forms, and any specific structure and / or function described herein is merely illustrative. Based on the present application, it should be understood by those skilled in the art that an aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number and aspect described herein can be used to implement the device and / or practice the method. In addition, other structures and / or functionalities other than one or more of the aspects described herein can be used to implement this device and / or practice this method.

[0043] It should also be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present application. The drawings only show components related to the present application rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0044] Additionally, in the following description, specific details are provided to facilitate a thorough understanding of the examples. However, it will be understood by those skilled in the art that the examples can be practiced without these specific details.

[0045] Traditional two-way alignment equipment, such as the patent document with publication number CN111928788A, discloses a two-way spectral confocal flat plate thickness detection system and its dual optical axis calibration method, which mainly uses the light energy method to quantitatively adjust the system parallelism and align the confocal probe optical axis. Although leveling and alignment can be achieved, when the measured flat plate is tilted, the calibrated two-way spectral confocal system is also tilted. Secondly, finding the position with the maximum light energy requires continuous adjustment, and there is no clear adjustment direction and adjustment amount, which makes the measurement and calibration process cumbersome.

[0046] Based on this, the embodiment of the present specification proposes a new bidirectional alignment scheme: when the first spectral confocal system forms a first angle with the direction of the optical symmetry axis, the first spectral confocal system is translated for a first time by a fixed distance relative to the marking plate along the optical symmetry axis, and the difference between the first distance and the second distance measured by the first spectral confocal system before and after the first translation is obtained; after the marking plate is rotated around a first vertical direction such as the z-axis by a set angle, the first spectral confocal system is translated for a second time by a fixed distance relative to the marking plate along the optical symmetry axis, and the difference between the third distance and the fourth distance measured by the first spectral confocal system before and after the second translation is obtained; the first angle is obtained by solving the first sinusoidal relationship and the second sinusoidal relationship of the two translations, and finally the coaxiality of the bidirectional spectral confocal system is achieved, and at the same time, the working distance overlap between the bidirectional imaging alignment system and the bidirectional spectral confocal system is measured and calibrated to improve reliability.

[0047] The technical solutions provided by various embodiments of the present application are described below in conjunction with the accompanying drawings.

[0048] like Figure 1 As shown, a bidirectional alignment measurement and calibration device provided in an embodiment of the present specification includes a first spectral confocal system 1, a second spectral confocal system 2, a first imaging alignment system 3, a second imaging alignment system 4, a marking plate 5, a detector (not shown) and a bidirectional alignment module 8. The marking plate 5 is provided with a coaxial alignment mark 6 and a working distance alignment mark 7.

[0049] The first spectral confocal system and the second spectral confocal system are respectively arranged on two sides of the bidirectional alignment module, such as respectively arranged on the upper and lower sides of the bidirectional alignment module.

[0050] The first imaging alignment system and the second imaging alignment system are respectively spaced apart from the first spectral confocal system by a preset distance along the optical symmetry axis of the bidirectional alignment module, and are also respectively arranged on both sides of the bidirectional alignment module; if the first imaging alignment system and the second imaging alignment system are relatively arranged on the right side of the two spectral confocal systems and are spaced apart from the two spectral confocal systems by a preset distance, the first imaging alignment system and the second imaging alignment system are also respectively arranged on the upper and lower sides of the bidirectional alignment module.

[0051] The marking plate is arranged on the upper side of the bidirectional alignment module.

[0052] To facilitate the measurement and calibration of the bidirectional alignment, a coordinate system is established, and the optical symmetry axis is used as one dimension in the three-dimensional coordinates. The first spectral confocal system and the optical symmetry axis form a first plane, and there is a first vertical direction perpendicular to the first plane, and the first vertical direction is used as another dimension in the three-dimensional coordinates;

[0053] The first vertical direction and the optical symmetry axis form a second plane, and there is a second vertical direction perpendicular to the second plane, and the second vertical direction is used as the coordinate of another direction dimension in the three-dimensional coordinates.

[0054] Wherein, when the first spectral confocal system forms a first angle with the direction of the optical symmetry axis, the first spectral confocal system is first translated by a fixed distance relative to the marking plate along the direction of the optical symmetry axis, and a first distance obtained by measuring the distance on the marking plate by the first spectral confocal system before the first translation and a second distance obtained by measuring the distance on the marking plate by the first spectral confocal system after the first translation are respectively obtained, and a difference between the first distance and the second distance is obtained;

[0055] A first sinusoidal relationship is formed according to the first angle, the second angle between the marking plate and the optical symmetry direction, the fixed distance, and the difference between the first distance and the second distance;

[0056] After the marking plate is rotated about the first vertical rotation to a set angle, that is, when the first spectral confocal system and the optical symmetry axis are at a third angle, the first spectral confocal system is translated for a second time along the optical symmetry axis relative to the marking plate by a fixed distance, and a third distance obtained by the first spectral confocal system on the marking plate before the second translation and a fourth distance obtained by the first spectral confocal system on the marking plate after the second translation are obtained, and a difference between the third distance and the fourth distance is obtained;

[0057] A second sinusoidal relationship is formed according to the first angle, the second angle between the marking plate and the optical symmetry axis, the fixed distance, the set angle, and the difference between the third distance and the fourth distance;

[0058] According to the first sinusoidal relationship and the second sinusoidal relationship, a first angle is obtained between the first spectral confocal system and the direction of the optical symmetry axis, and a second angle is obtained between the marking plate and the direction of the optical symmetry axis, and the first spectral confocal system is adjusted to be perpendicular to the direction of the optical symmetry axis, and the marking plate is adjusted to be parallel to the direction of the optical symmetry axis;

[0059] Determine that the first spectral confocal system is perpendicular to the first vertical and the marking plate is perpendicular to the first vertical; determine that the first spectral confocal system is parallel to the second vertical and the marking plate is perpendicular to the second vertical, that is, determine that the coordinate axes in the three-dimensional coordinate system are mutually perpendicular. And the second spectral confocal system is parallel to the second vertical, use the first spectral confocal system and the second spectral confocal system to image the coaxial alignment marks of the same size on the marking plate, respectively, and measure that the distance between the first spectral confocal system and the marking plate is the same as the distance between the second spectral confocal system and the marking plate, and when the spectral signal amplitudes are the same, the optical axes of the two spectral confocal systems are coaxial;

[0060] Keep the marking plate still, and make sure that the working distance of the first imaging alignment system and the working distance of the second imaging alignment system overlap with the working distances of the two-spectral confocal systems respectively.

[0061] The present application can measure and calibrate the coaxiality of the bidirectional spectral confocal system in the bidirectional alignment device, and at the same time measure and calibrate the working distance overlap between the bidirectional imaging alignment system and the bidirectional spectral confocal system, thereby improving the reliability of the alignment device. Thus, the constructed optical module can realize the online six-axis alignment function in the application scenario, thereby improving the alignment accuracy.

[0062] The present application can directly calculate the inclination of the marking plate and the inclination of the spectral confocal optical axis through the measured values ​​before and after the rotating marking plate, quantify the adjusted inclination, and at the same time avoid the same working distance in the tilted state of the dual-spectral confocal system after calibration caused by the inclination of the marking plate. The dual-spectral confocal system can remain parallel to the moving direction of the translation stage, which is beneficial to the measurement and adjustment of the target to be measured after calibration.

[0063] The present application simultaneously achieves the purpose of overlapping the working distances of the dual-spectrum confocal system and the dual-imaging alignment system.

[0064] In some embodiments, Figure 1 As shown, the first spectral confocal system, the second spectral confocal system, the first imaging alignment system, and the second imaging alignment system are all installed on the same bidirectional alignment module.

[0065] In some embodiments, the bidirectional alignment module is arranged in a horizontal position or a vertical position.

[0066] In some embodiments, the coaxial alignment mark is used for alignment of a spectral confocal system; and the working distance alignment mark is used for alignment of an imaging alignment system.

[0067] Two marking plates are symmetrically arranged on both sides of the bidirectional alignment module, and the coaxial alignment marks and working distance alignment marks on each marking plate are symmetrically arranged along the optical symmetry axis.

[0068] like Figure 8 As shown, a coordinate system is established, and two upper and lower marking plates are used to achieve six-degree-of-freedom adjustment. The first marking plate is the upper marking plate 51, and the second marking plate is the lower marking plate 52. The two marking plates respectively carry coaxial alignment marks such as 61 and 62 corresponding to the spectral confocal alignment system, and respectively carry working distance alignment marks such as 71 and 72 corresponding to the imaging alignment system. During the six-degree-of-freedom adjustment process, the projections of the coaxial alignment marks 61 and 62 on the optical symmetry axis and the second vertical plane (such as the XZ plane) overlap. The projections of the working distance alignment marks such as 71 and 72 on the optical symmetry axis and the second vertical plane (such as the XZ plane) overlap, thereby ensuring the purpose of dual-spectrum confocal co-optical axis and alignment imaging lens co-optical axis.

[0069] In some embodiments, the marking area and the non-marking area on the marking plate form different reflection contrasts, and the marking area is used to enhance or weaken reflection; one of the marking area or the non-marking area in the marking plate is set as a chrome-plated reflective surface.

[0070] Specifically, the marking area and the non-marking area on the marking plate form a high reflection contrast, and the marking area can have enhanced or weakened reflection. The marking area on the marking plate 5 can be a chrome-plated reflective surface, or the non-marking area is a chrome-plated reflective surface.

[0071] In some embodiments, the bidirectional alignment module is disposed on a rotating table, the rotation axis of the rotating table coincides with the optical symmetry axis of the bidirectional alignment module, the optical symmetry axis is the X direction, the second vertical direction is the Y direction, and the first vertical direction is the Z direction.

[0072] like Figure 1 , 3 -8, the optical symmetry axis is the X direction, the second vertical direction is the Y direction, and the first vertical direction is the Z direction.

[0073] In some embodiments, the rotating stage is a multi-dimensional rotating stage, so as to move the bidirectional alignment module through the multi-dimensional rotating stage to achieve distance measurement with a two-spectrum confocal system.

[0074] For example, the bidirectional alignment module 8 can be mounted on a multi-dimensional rotating platform. During the process of the first spectral confocal 1 measuring the distance between the marking plate 5 , the marking plate 5 can be fixed and the bidirectional alignment module 8 can be moved to achieve distance measurement at two positions.

[0075] The present application enables the dual-spectrum confocal system and the dual-imaging alignment system to measure and calibrate the same mark by means of rotation, thereby avoiding measurement and calibration errors introduced by the alignment mark plate.

[0076] In some embodiments, the first imaging alignment system and the second imaging alignment system share a detector, which is an image sensor.

[0077] In combination with the above embodiments, the embodiments of this specification further provide a bidirectional alignment calibration method, comprising the following steps:

[0078] Step 1: When the first spectral confocal system forms a first angle with the direction of the optical symmetry axis, the first spectral confocal system is translated for a first time for a fixed distance relative to the marking plate along the direction of the optical symmetry axis, and a first distance obtained by measuring the distance on the marking plate by the first spectral confocal system before the first translation and a second distance obtained by measuring the distance on the marking plate by the first spectral confocal system after the first translation are obtained, and the difference between the first distance and the second distance is obtained.

[0079] Step 2: A first sinusoidal relationship is formed according to the first angle, the second angle between the marking plate and the optical symmetry direction, the fixed distance, and the difference between the first distance and the second distance.

[0080] Step 3: After the marking plate is rotated around the first vertical rotation angle, that is, when the first spectral confocal system forms a third angle with the optical symmetry axis, the first spectral confocal system is translated a second time by a fixed distance relative to the marking plate along the optical symmetry axis, and the third distance obtained by the first spectral confocal system on the marking plate before the second translation and the fourth distance obtained by the first spectral confocal system on the marking plate after the second translation are obtained, and the difference between the third distance and the fourth distance is obtained.

[0081] Step 4: A second sinusoidal relationship is formed according to the first angle, the second angle between the marking plate and the optical symmetry axis, the fixed distance, the set angle, and the difference between the third distance and the fourth distance.

[0082] Step 5: According to the first sinusoidal relationship and the second sinusoidal relationship, obtain a first angle between the first spectral confocal system and the direction of the optical symmetry axis, and a second angle between the marking plate and the direction of the optical symmetry axis, and adjust the first spectral confocal system to be perpendicular to the direction of the optical symmetry axis and the marking plate to be parallel to the direction of the optical symmetry axis.

[0083] Step 6: Determine that the first spectral confocal system is perpendicular to the first vertical and the marking plate is perpendicular to the first vertical; when the first spectral confocal system is parallel to the second vertical, the marking plate is perpendicular to the second vertical, and the second spectral confocal system is parallel to the second vertical, and the marking plate is fixed, use the first spectral confocal system and the second spectral confocal system to image the coaxial alignment marks of the same size on the marking plate respectively, and when the distance between the first spectral confocal system and the marking plate is measured to be the same as the distance between the second spectral confocal system and the marking plate, and the spectral signal amplitudes are the same, the optical axes of the two spectral confocal systems are coaxial.

[0084] Step 7: Keep the marking plate still and make sure that the working distance of the first imaging alignment system and the working distance of the second imaging alignment system overlap with the working distances of the two spectral confocal systems.

[0085] Specifically, the calibration process of the first spectrum confocal system and the second spectrum confocal system is similar, and only the first spectrum confocal system is used as an example for explanation. Figure 1 For example, the direction of the optical symmetry axis is the x-axis, the second vertical direction is the y-axis, and the first vertical direction is perpendicular to the xy plane and outward is the z-axis.

[0086] In the first step, when the first spectral confocal system forms a first angle α (unknown) with the direction of the optical symmetry axis, the first spectral confocal system is turned on to measure the distance of the marking plate to obtain a first distance.

[0087] In the second step, the marking plate is translated along the optical symmetry axis by a fixed distance L, and the marking plate is measured again using the first spectral confocal system to obtain a second distance, and the difference Δ1 between the first distance and the second distance is calculated.

[0088] The third step is to use the first angle α, the second angle β (unknown) between the marking plate and the optical symmetry axis, the fixed distance L and Δ1, as follows: Figure 2 The first sinusoidal relationship obtained in the above part is as shown in Formula 1:

[0089]

[0090] In the fourth step, after rotating the marking plate around the first vertical direction by a set angle θ, the first spectral confocal system is used to measure the distance of the marking plate to obtain a third distance.

[0091] Step 5: Continue to translate the marking plate along the optical symmetry axis for a fixed distance L, and use the first spectral confocal system to measure the marking plate to obtain a fourth distance, and calculate the difference Δ2 between the third distance and the fourth distance, as shown in Figure 2 The second sinusoidal relationship obtained as shown in the following part is as shown in Formula 2:

[0092]

[0093] Step 6. Obtain the first angle α and the second angle β (i.e., the angle between the intersection of the marking plate and the XY plane and the x-axis direction) according to Formula 1 and Formula 2. Repeat the above adjustments and calculations to adjust the first spectral confocal system to be perpendicular to the optical symmetry axis and the marking plate to be parallel to the optical symmetry axis.

[0094] Similarly, the angle between the intersection line of the marking plate and the yz plane and the z-axis direction, and the angle between the first spectral confocal system and the z-axis direction are calculated.

[0095] The angle between the intersection line of the marking plate and the xz plane and the y-axis direction, and the angle between the first spectral confocal system and the y-axis direction are calculated.

[0096] Finally, it is at least determined that the intersection line of the marking plate and the xz plane is perpendicular to the y-axis direction, and the first spectral confocal system is parallel to the y-axis direction.

[0097] Similarly, a second spectral confocal system may be implemented parallel to the y-axis.

[0098] There are marks on the marking plate with a size comparable to that of the spectral confocal spot, which form reflection enhancement or reflection reduction for the coaxial alignment of the opposing dual-spectral confocal.

[0099] like Figure 3 , Figure 4As shown, the optical symmetry axis is set on the rotating table, and the rotation axis of the rotating table coincides with the optical symmetry axis. Step 7, keep the current marking plate still, rotate the rotating table, so that the first spectral confocal system and the second spectral confocal system image the same small-size alignment mark on the marking plate. When the two spectral confocal systems measure the same distance and the same spectral signal amplitude (that is, the echo signal intensity remains consistent), the two spectral confocal systems are coaxial, and the optical axis is parallel to the Y axis (perpendicular to the rotation axis). At this time, the opposite dual-spectral confocal systems are coaxial and the axis is parallel to the Y axis (that is, perpendicular to the bidirectional alignment module output).

[0100] Figure 5 This is a schematic diagram of a dual-spectrum confocal system in which the optical axis is parallel to the Y axis but the spectral signal amplitudes are different. At this time, the dual-spectrum confocal system has not achieved coaxial measurement and calibration.

[0101] In the eighth step, the marking plate is kept stationary, and the working distances of the first imaging alignment system and the second imaging alignment system are determined to overlap with the working distances of the two-spectral confocal systems.

[0102] like Figure 6 As shown, the position of the first imaging alignment system is adjusted so that the detector can form a clear image of the working distance alignment mark on the marking plate, thereby completing the overlapping measurement and calibration of the working distance of the first imaging alignment system and the working distance of the spectral confocal system.

[0103] Figure 7 The figure shows a schematic diagram of imaging calibration of the alignment mark at the same working distance by rotating the turntable 180 degrees and adjusting the position of the second imaging alignment system. When the imaging is clear and the imaging position overlaps with the position of the first imaging alignment system, the calibration of the working distance of the opposing dual imaging alignment system to be the same as that of the opposing dual spectral confocal system is completed.

[0104] In the method for coaxial calibration of the spectral confocal system and overlapping calibration of the working distance of the spectral confocal system and the imaging alignment system provided in the present application, after the first spectral confocal system calibrates the marking plate to be parallel, the marking plate can only be translated relative to the optical module along the direction of the rotation axis.

[0105] By rotating the central axis of the optical module on a turntable, the two oppositely installed spectral confocal systems and imaging alignment systems can measure the distance and image the marking plate at the same position, thereby achieving the coaxial adjustment of the dual-spectral confocal system with the axis perpendicular to the rotation axis, and at the same time, the overlapping working distances of the dual-spectral confocal system and the imaging alignment system can be measured and calibrated.

[0106] like Figure 8As shown, adjust the angle and transverse coordinate position of the marking plate, calculate the inclination angle of the marking plate and the inclination angle of the spectral confocal optical axis, and adjust the spectral confocal optical axis to be parallel to the Y axis according to the calculation result of the inclination angle, so as to realize the parallelism of the optical axis of the dual-spectral confocal system. Then, measure the maximum signal position of the small mark through spectral confocal measurement, adjust the horizontal position of the dual-spectral confocal optical axis, and realize the coincidence of the optical axis of the dual-spectral confocal system. At this time, the optical axis and the Y axis remain coincident. Keep the positions of the marking plates 51 and 52 unchanged, adjust the positions of the lenses 3 and 4, so that the best focal plane position of the alignment imaging system overlaps with the positions of the marking plates 51 and 52 respectively, and complete the calibration of the parallelism of the optical axis of the bidirectional alignment imaging lens; adjust the horizontal position of the bidirectional alignment imaging lens so that the marks 71 and 72 are located at the same position in the camera field of view. This operation realizes the coincidence of the optical axes of the dual lenses of the alignment imaging system, and the optical axis is parallel to the dual-spectral confocal system. Because the positions of the marking plates 51 and 52 are kept unchanged after the dual-spectral confocal system is adjusted, the working distance of the bidirectional alignment imaging lens overlaps with the working distance of the dual-spectral confocal system.

[0107] The present application can measure and calibrate the coaxiality of the bidirectional spectral confocal system in the bidirectional alignment device, and at the same time measure and calibrate the working distance overlap between the bidirectional imaging alignment system and the bidirectional spectral confocal system, thereby improving the reliability of the alignment device. The constructed optical module can realize the online six-axis alignment function in the application scenario, thereby improving the alignment accuracy.

[0108] In combination with the above embodiments, the present application also provides a bidirectional alignment device, that is, after the calibration is completed, the first spectral confocal system and the second spectral confocal system are coaxial, and are arranged vertically and oppositely on both sides of the bidirectional alignment module. The first imaging alignment system and the second imaging alignment system are respectively arranged vertically and oppositely on both sides of the bidirectional alignment module, and overlap with the working distances of the two spectral confocal systems, so as to perform rotational alignment and leveling on other devices on both sides of the bidirectional alignment device.

[0109] The same or similar parts between the various embodiments in this specification can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the product embodiment described later, since it corresponds to the method, the description is relatively simple, and the relevant parts can be referred to the partial description of the system embodiment.

[0110] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A bidirectional alignment calibration device, characterized in that: include: A first spectral confocal system, a second spectral confocal system, a first imaging alignment system, a second imaging alignment system, a marking plate, a detector and a bidirectional alignment module; The first spectral confocal system and the second spectral confocal system are respectively arranged on two sides of the bidirectional alignment module; The first imaging alignment system and the second imaging alignment system are respectively spaced apart from the first spectral confocal system by a preset distance along the optical symmetry axis direction of the bidirectional alignment module, and are also respectively arranged on both sides of the bidirectional alignment module; The marking plate is arranged on at least one side of the bidirectional alignment module; the marking plate is provided with a coaxial alignment mark and a working distance alignment mark; The first spectral confocal system and the optical symmetry axis form a first plane, and there is a first vertical direction perpendicular to the first plane; The first vertical direction and the optical symmetry axis form a second plane, and there is a second vertical direction perpendicular to the second plane; Wherein, when the first spectral confocal system forms a first angle with the direction of the optical symmetry axis, the first spectral confocal system is first translated by a fixed distance relative to the marking plate along the direction of the optical symmetry axis, and a first distance obtained by measuring the distance on the marking plate by the first spectral confocal system before the first translation and a second distance obtained by measuring the distance on the marking plate by the first spectral confocal system after the first translation are respectively obtained, and a difference between the first distance and the second distance is obtained; A first sinusoidal relationship is formed according to the first angle, the second angle between the marking plate and the optical symmetry direction, the fixed distance, and the difference between the first distance and the second distance; After the marking plate is rotated about a first vertical rotation to a set angle, the first spectral confocal system is secondarily translated by a fixed distance relative to the marking plate along the optical symmetry axis, and a third distance obtained by the first spectral confocal system on the marking plate before the second translation and a fourth distance obtained by the first spectral confocal system on the marking plate after the second translation are respectively obtained, and a difference between the third distance and the fourth distance is obtained; A second sinusoidal relationship is formed according to the first angle, the second angle between the marking plate and the optical symmetry axis, the fixed distance, the set angle, and the difference between the third distance and the fourth distance; According to the first sinusoidal relationship and the second sinusoidal relationship, a first angle is obtained between the first spectral confocal system and the direction of the optical symmetry axis, and a second angle is obtained between the marking plate and the direction of the optical symmetry axis, and the first spectral confocal system is adjusted to be perpendicular to the direction of the optical symmetry axis, and the marking plate is adjusted to be parallel to the direction of the optical symmetry axis; Determine that the first spectral confocal system is perpendicular to the first vertical, and the marking plate is perpendicular to the first vertical; when the first spectral confocal system is parallel to the second vertical, and the marking plate is perpendicular to the second vertical, and the second spectral confocal system is parallel to the second vertical, respectively use the first spectral confocal system and the second spectral confocal system to image the coaxial alignment marks of the same size on the marking plate, and when it is measured that the distance between the first spectral confocal system and the marking plate is the same as the distance between the second spectral confocal system and the marking plate, and the spectral signal amplitudes are the same, the optical axes of the two spectral confocal systems are coaxial; Keep the marking plate still, and make sure that the working distance of the first imaging alignment system and the working distance of the second imaging alignment system overlap with the working distances of the two-spectral confocal systems respectively.

2. The bidirectional alignment calibration device according to claim 1, characterized in that: The first spectral confocal system, the second spectral confocal system, the first imaging alignment system, and the second imaging alignment system are all installed on the same bidirectional alignment module; The bidirectional alignment module is placed horizontally or vertically.

3. The bidirectional alignment calibration device according to claim 1, characterized in that: The coaxial alignment mark is used for alignment of the spectral confocal system; the working distance alignment mark is used for alignment of the imaging alignment system; Two marking plates are symmetrically arranged on both sides of the bidirectional alignment module, and the coaxial alignment marks and working distance alignment marks on each marking plate are symmetrically arranged along the optical symmetry axis.

4. The bidirectional alignment calibration device according to claim 1, characterized in that: The marked area and the non-marked area on the marking plate form different reflection contrasts, and the marked area is used to enhance or weaken reflection; One of the marking area or the non-marking area in the marking plate is set as a chrome-plated reflective surface.

5. The bidirectional alignment calibration device according to claim 1, characterized in that: The bidirectional alignment module is arranged on a rotating table, the rotating axis of the rotating table coincides with the optical symmetry axis of the bidirectional alignment module, the rotating axis is the X direction, the second vertical direction is the Y direction, and the first vertical direction is the Z direction.

6. The bidirectional alignment calibration device according to claim 5, characterized in that: The rotating stage is a multi-dimensional rotating stage, and the bidirectional alignment module is moved by the multi-dimensional rotating stage to achieve distance measurement with the two-spectrum confocal system.

7. The bidirectional alignment calibration device according to claim 1, characterized in that: The first imaging alignment system and the second imaging alignment system share a detector, which is an image sensor.

8. A bidirectional alignment calibration method, characterized in that: include: When the first spectral confocal system forms a first angle with the direction of the optical symmetry axis, the first spectral confocal system is first translated by a fixed distance relative to the marking plate along the direction of the optical symmetry axis, and a first distance obtained by the first spectral confocal system on the marking plate before the first translation and a second distance obtained by the first spectral confocal system on the marking plate after the first translation are respectively obtained, and a difference between the first distance and the second distance is obtained; A first sinusoidal relationship is formed according to the first angle, the second angle between the marking plate and the optical symmetry axis, the fixed distance, and the difference between the first distance and the second distance; After the marking plate is rotated about a first vertical rotation to a set angle, the first spectral confocal system is secondarily translated by a fixed distance relative to the marking plate along the optical symmetry axis, and a third distance obtained by the first spectral confocal system on the marking plate before the second translation and a fourth distance obtained by the first spectral confocal system on the marking plate after the second translation are respectively obtained, and a difference between the third distance and the fourth distance is obtained; A second sinusoidal relationship is formed according to the first angle, the second angle between the marking plate and the optical symmetry axis, the fixed distance, the set angle, and the difference between the third distance and the fourth distance; According to the first sinusoidal relationship and the second sinusoidal relationship, a first angle is obtained between the first spectral confocal system and the direction of the optical symmetry axis, and a second angle is obtained between the marking plate and the direction of the optical symmetry axis, and the first spectral confocal system is adjusted to be perpendicular to the direction of the optical symmetry axis, and the marking plate is adjusted to be parallel to the direction of the optical symmetry axis; Determine that the first spectral confocal system is perpendicular to the first vertical direction, and the marking plate is perpendicular to the first vertical direction; When it is determined that the first spectral confocal system is parallel to the second vertical, the marking plate is perpendicular to the second vertical, and the second spectral confocal system is parallel to the second vertical, and the marking plate is fixed, the first spectral confocal system and the second spectral confocal system are respectively used to image the coaxial alignment marks of the same size on the marking plate, and when it is measured that the distance between the first spectral confocal system and the marking plate is the same as the distance between the second spectral confocal system and the marking plate, and the spectral signal amplitudes are the same, the optical axes of the two spectral confocal systems are coaxial; Keep the marking plate still, and make sure that the working distance of the first imaging alignment system and the working distance of the second imaging alignment system overlap with the working distances of the two-spectral confocal systems respectively.

9. The bidirectional alignment calibration method according to claim 8, characterized in that: For the same working distance alignment mark, when the imaging is clear and the imaging position overlaps with the position of the first imaging alignment system or the second imaging alignment system, it is determined that the working distances of the two imaging alignment systems are the same as the working distance of the bidirectional spectral confocal system.

10. A bidirectional alignment device, characterized in that: By applying the bidirectional alignment measurement and calibration device as described in any one of claims 1-7, or by applying the bidirectional alignment measurement and calibration method as described in claim 8 or 9, the first spectral confocal system and the second spectral confocal system are coaxially arranged on both sides of the bidirectional alignment module in opposition and vertical orientation, and the first imaging alignment system and the second imaging alignment system are respectively arranged on both sides of the bidirectional alignment module in opposition and vertical orientation, and overlap with the working distances of the two spectral confocal systems, so as to rotationally align and level other devices on both sides of the bidirectional alignment device.

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