An integrated interferometric measurement head and an interferometric measurement system

Abstract

The present invention belongs to the field of precision measurement technology, and specifically relates to an integrated interferometric measurement head and an interferometric measurement system. The integrated interferometric measurement head includes two groups of integrated interferometric measurement components, one group performs shape measurement of the measured object, and the other group realizes the position feedback of the first group, which can better compensate for mechanical movement errors; at the same time, the present invention adopts a group of PZT modules to simultaneously realize the interference phase adjustment of the two groups of measurement components, which can reduce the number of PZT modules. The present invention reduces the volume of the interferometric measurement system as a whole, reduces the difficulty of compensating mechanical errors and phase errors, and improves the accuracy of three-dimensional shape measurement.

Description

Technical Field

[0001] The invention belongs to the technical field of precision measurement, and in particular relates to an integrated interference measurement head and an interference measurement system. Background Art

[0002] In order to complete the measurement of the three-dimensional shape of the object to be measured, the integrated interferometric measurement head needs to move in multiple degrees of freedom such as horizontal, vertical, and rotation. These movements require the cooperation of a precision translation stage. Because there are mechanical errors in the movement of the mechanical axis (usually the error is at the micron level, or even larger, and the error is too large for nanometer precision measuring instruments), it is necessary to compensate for the error through optical measurement methods. Since the errors of multiple degrees of freedom all need to be compensated, this leads to the need for multiple measurement heads in a measurement system, including a shape measurement head and a reference measurement head. In order to perform high-precision shape measurement, phase modulation (i.e., phase-shifting interferometric measurement technology) is required. Due to the need for phase modulation, a single measurement head needs to use a single PZT (piezoelectric ceramics, which is the mainstream phase modulation module on the market in the field of interferometric measurement) module, and multiple measurement heads need to use multiple PZT modules. Due to the hysteresis and creep of the PZT module, this will cause the measurement head to introduce phase shift errors during the measurement process, which is also one of the important error sources of the measurement system. Therefore, the increase in the number of PZT modules will lead to an increase in error factors, resulting in increased difficulty in error compensation and calibration. Summary of the invention

[0003] In view of this, the present invention proposes an integrated interferometric measurement head, which integrates two groups of interferometric measurement components, one group performs the shape measurement of the measured object, and the other group realizes the position feedback of the first group, which can better compensate for the mechanical movement error; at the same time, the present invention uses a group of PZT modules to simultaneously realize the interference phase adjustment of the two groups of measurement components, which can reduce the number of PZT modules. The present invention reduces the volume of the interferometric measurement system as a whole, reduces the difficulty of compensating for mechanical errors and phase errors, and improves the accuracy of three-dimensional shape measurement.

[0004] In order to achieve the above technical objectives, the specific technical solutions adopted by the present invention are:

[0005] An integrated interferometric measurement head, comprising:

[0006] A first light inlet, used for point emission and point reception of light;

[0007] A second light inlet, used for point emission and point reception of light;

[0008] a first collimating lens, with a focus set at the entrance of the first light;

[0009] a second collimating lens, with a focus set at the entrance of the second light;

[0010] A first beam splitter, transmitting part of the outgoing light path of the first collimating lens and reflecting part of the outgoing light path, wherein at least a part of the reflected light returns to the first collimating lens along the original path, and the transmitted light is transmitted to the first object to be measured;

[0011] A second beam splitter, transmitting part of the outgoing light path of the second collimating lens and reflecting part of the outgoing light path, returning at least a part of the reflected light to the optical axis of the second collimating lens along the original path, and transmitting the transmitted light to the second object to be measured;

[0012] Wherein: the integrated interferometric measurement head also includes a PZT module; the PZT module drives the first beam splitter and the second beam splitter to perform linear motion in the same moving mode, and adjusts the optical path between the first beam splitter and the first collimating lens and the optical path between the second beam splitter and the second collimating lens.

[0013] Furthermore, the integrated interferometric measurement head further comprises a first focusing lens, and the first focusing lens is arranged on the transmission output light path of the first beam splitter.

[0014] Furthermore, the integrated interferometric measurement head further comprises a second focusing lens, and the first focusing lens is arranged on the transmission output light path of the second beam splitter.

[0015] Furthermore, the optical axes of the first focusing lens and the second focusing lens coincide with each other.

[0016] Furthermore, the integrated interferometric measurement head further comprises a first reflector; the optical axis of the first collimating lens is perpendicular to the reflective surface of the first beam splitter; and the first reflector realizes the mutual transmission of the light between the beam splitter and the first collimating lens.

[0017] Furthermore, the integrated interferometric measurement head further comprises a second reflector; the optical axis of the second collimating lens is perpendicular to the reflective surface of the second beam splitter; and the second reflector realizes the mutual transmission of the light between the beam splitter and the second collimating lens.

[0018] Furthermore, the first measured object is a position reference surface; the position reference surface forms a coordinate reference of the integrated interferometric measurement head; and the integrated interferometric measurement head measures the morphology of the second measured object.

[0019] Furthermore, the integrated interference measurement head is installed on a rotating shaft; and the position reference surface is an arc surface.

[0020] Furthermore, the light consists of at least two groups of monochromatic lights.

[0021] At the same time, the present invention also proposes an interferometric measurement system, comprising the above-mentioned integrated interferometric measurement head, and also comprising a motion component and a reference system component; the motion component drives the integrated interferometric measurement head and / or the second measured object to move, so that the measured area of ​​the second measured object is within the detection range of the measurement head;

[0022] The reference system assembly includes at least one set of reference measuring heads and at least one set of coordinate reference surfaces. The reference measuring heads receive the monochromatic light reflected by the coordinate reference surfaces based on the monochromatic light irradiating the coordinate reference surfaces, so that the monochromatic light reflected by the coordinate reference surfaces interferes with a portion of the monochromatic light incident on the reference measuring heads.

[0023] The first light inlet, the first collimating lens and the first beam splitter and / or the first focusing lens form a group of the reference measuring heads; the position reference surfaces form a group of the coordinate reference surfaces.

[0024] By adopting the above technical solution, the present invention can also bring the following beneficial effects:

[0025] The present invention provides a first focusing lens and / or a second focusing lens to convert light into convergent light for shape measurement and / or position calibration of an integrated interferometric measurement head; this can improve light utilization, further improve measurement accuracy, and expand the measurement range;

[0026] The first focusing lens and the second focusing lens of the present invention are coaxially arranged, which can further reduce the volume;

[0027] The present invention sets a first reflector and / or a second reflector, and sets the optical axis of the first collimating lens and / or the second collimating lens to be perpendicular to the reflecting surface of the beam splitter, so as to shorten the length of the measuring head;

[0028] The integrated interferometric measuring head of the present invention is installed on a rotating shaft, and the position reference surface is set as a curved surface, so that inaccurate measurement results caused by mechanical errors of the rotating shaft are avoided in working conditions where the integrated interferometric measuring head needs to rotate.

[0029] The light of the present invention is composed of at least two groups of monochromatic lights, which can break through the measurement range of λ / 2 and achieve nanometer precision measurement (5 to 0.05 nm). BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, 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 invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0031] Figure 1 A schematic diagram of the optical path structure of an integrated interferometric measurement head in a specific embodiment of the present invention;

[0032] Figure 2 It is a schematic diagram of the optical path structure of another integrated interferometric measurement head in a specific embodiment of the present invention;

[0033] Figure 3 It is a structural schematic diagram of an interference measurement device in a specific implementation manner of the present invention;

[0034] Figure 4 It is a schematic diagram of the structure of another reference measuring head in a specific embodiment of the present invention;

[0035] Wherein: 1. support frame; 2. reference surface one; 3. mechanical arm one; 4. reference measuring head one; 5. rotation axis one; 6. object measuring head; 7. measured object; 8. rotation axis two; 9. reference surface two; 10. translation stage; 11. reference measuring head two; 12. reference measuring head three; 13. reference surface three; 14. light source; 15. detector module; 16. signal line; 17. computer; 18. second focusing lens; 19. second spectroscope; 20. first reflector; 21. PZT module; 22. incident light; 23. reflected light; 24. first collimating lens; 25. second collimating lens; 26. cavity; 27. lens four; 28. optical fiber; 29. ​​second reflector; 30. first spectroscope; 31. first focusing lens; 32. first light entrance; 33. second light entrance. DETAILED DESCRIPTION

[0036] The embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0037] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. The present invention can also be implemented or applied through other different specific embodiments, 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 invention. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work belong to the scope of protection of the present invention.

[0038] 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 invention, 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 of aspects 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.

[0039] It should also be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present invention. The drawings only show components related to the present invention 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.

[0040] 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 aspects described may be practiced without these specific details.

[0041] In one embodiment of the present invention, an integrated interferometric measurement head is provided, such as Figure 1 , 2 As shown, including:

[0042] A first light inlet 32, used for point emission and point reception of light;

[0043] A second light inlet 33, used for point emission and point reception of light;

[0044] A first collimating lens 24, with a focus set at the first light entrance 32;

[0045] A second collimating lens 25, with a focus set at the second light entrance 33;

[0046] The first beam splitter 30 transmits part of the outgoing light path of the first collimating lens 24 and reflects part of it, and at least a part of the reflected light returns to the first collimating lens 24 along the original path, and the transmitted light is transmitted to the first object to be measured;

[0047] The second beam splitter 19 transmits part of the outgoing light path of the second collimating lens 25 and reflects part of it, and at least a part of the reflected light returns to the optical axis of the second collimating lens 25 along the original path, and the transmitted light is transmitted to the second object to be measured;

[0048] The integrated interferometer measurement head further comprises a PZT module 21 ; the PZT module 21 drives the first beam splitter 30 and the second beam splitter 19 to perform linear motion in the same manner, and adjusts the optical path between the first beam splitter 30 and the reference surface 2 and the optical path between the second beam splitter 19 and the object 7 to be measured.

[0049] The specific position of the above optical components is not limited in this embodiment.

[0050] In this embodiment, the first group of interference measurement components includes a first light inlet 32, a first collimating lens 24 and a first beam splitter 30; the first light inlet 32 ​​sends the light to the first collimating lens 24, where the light is refracted into parallel light, and the parallel light is transmitted to the first beam splitter 30. The reflection surface of the first beam splitter 30 is arranged perpendicular to the parallel light, so that a part of the light returns along the original path and finally reaches the first collimating lens 24. The first collimating lens 24 forms the parallel light reflected by the first beam splitter 30 into reference light, and then refracts the reference light into convergent light and transmits it to the first light inlet 32; the light transmitted through the first beam splitter 30 is transmitted After reaching the first object to be measured, the light is reflected by the first object to be measured, and then transmitted through the first beam splitter 30 to form the measuring light, and finally reaches the first collimating lens 24, and is converged to the first light outlet by the first collimating lens 24; due to the optical path difference between the measuring light and the reference light, they will interfere at the first beam splitter 30 and produce interference fringes. When the distance between the first object to be measured and the first beam splitter 30 changes, the interference fringes also change. The detector module 15 detects the interference fringes, and based on the changing law of the interference fringes, the distance change between the first beam splitter 30 and the object to be measured can be obtained, and the morphology of the first object to be measured can be obtained according to the distance change.

[0051] The second group of interference measurement components includes a second light inlet 33, a second collimating lens 25 and a second beam splitter 19; the second light inlet 33 sends the light to the second collimating lens 25, where the light is refracted into parallel light, and the parallel light is transmitted to the second beam splitter 19. The reflection surface of the second beam splitter 19 is arranged perpendicular to the parallel light, so that a part of the light returns along the original path and finally reaches the second collimating lens 25. The second collimating lens 25 converts the parallel light reflected by the second beam splitter 19 into reference light, and then refracts the reference light into convergent light and transmits it to the second light inlet 33; the light transmitted through the second beam splitter 19 is transmitted to the second light inlet 33. After being delivered to the second object to be measured, it is reflected by the second object to be measured, and then the light transmitted by the second beam splitter 19 forms the measuring light, and finally reaches the second collimating lens 25, and is converged to the second light exit by the second collimating lens 25; due to the optical path difference between the measuring light and the reference light, interference will occur and interference fringes will appear. When the distance between the second object to be measured and the second beam splitter 19 changes, the interference fringes also change. The detector module 15 detects the interference fringes, and based on the changing law of the interference fringes, the distance change between the second beam splitter 19 and the object to be measured can be obtained, and the morphology of the second object to be measured can be obtained according to the distance change.

[0052] The two groups of interferometric measurement components of this embodiment are integrated together, and one group can be selected to measure the shape of the object 7 to be measured, and the other group can realize the position feedback of the first group, which can better compensate for the mechanical movement error;

[0053] In order to meet the needs of phase modulation, both sets of interferometric measurement components need to use PZT (piezoelectric ceramic) modules to adjust the phase difference and optical path difference in order to achieve accurate measurement. Because the PZT module 21 has deficiencies such as hysteresis and creep, this will cause the measuring head to introduce errors during the measurement process, which is also one of the important error sources of the system. Therefore, the increase in the number of PZT modules 21 will introduce more error factors, resulting in difficulty in error compensation and calibration. This embodiment can reduce the number of PZT modules 21 by simultaneously realizing the interferometric phase adjustment of two sets of measurement components through a group of PZT, reduce error factors, and thus reduce the measurement difficulty and improve measurement accuracy.

[0054] Meanwhile, in this embodiment, both sets of measuring components can be selected to measure the measured object 7 or both sets of measuring components can be used to perform position feedback.

[0055] In one embodiment, Figure 1 As shown, the integrated interferometric measurement head further includes a first focusing lens 31 , which is disposed on the transmission outgoing light path of the first beam splitter 30 .

[0056] In one embodiment, Figure 1 As shown, the integrated interferometric measurement head further includes a second focusing lens 18 , and a first focusing lens 31 is arranged on the transmission outgoing light path of the second beam splitter 19 .

[0057] The above two embodiments provide a first focusing lens 31 and / or a second focusing lens 18 to convert light into convergent light for topography measurement and / or position calibration of the integrated interferometric measurement head; this can improve light utilization, further improve measurement accuracy and expand the measurement range.

[0058] In one embodiment, the optical axes of the first focusing lens 31 and the second focusing lens 18 coincide, and the first focusing lens 31 and the second focusing lens 18 are coaxially arranged, which can reduce the radial volume of the integrated interferometer measurement head, make the integrated interferometer measurement head more compact, have higher flexibility and thus increase the measurement range.

[0059] In one embodiment, Figure 1 As shown, the integrated interferometric measurement head further includes a first reflector 20 ; the optical axis of the first collimating lens 24 is perpendicular to the reflective surface of the first beam splitter 30 ; the first reflector 20 realizes the mutual transmission of light between the beam splitter and the first collimating lens 24 .

[0060] In one embodiment, Figure 1 As shown, the integrated interferometric measurement head further includes a second reflector 29 ; the optical axis of the second collimating lens 25 is perpendicular to the reflective surface of the second beam splitter 19 ; and the second reflector 29 realizes the mutual transmission of light between the beam splitter and the second collimating lens 25 .

[0061] In the above embodiments, the first reflector 20 and / or the second reflector 29 are arranged, and the optical axis of the first collimating lens 24 and / or the second collimating lens 25 is arranged to be perpendicular to the reflecting surface of the beam splitter, so that the distance between the two beam splitters can be shortened, thereby reducing the axial length of the integrated interferometric measuring head, making the integrated interferometric measuring head more compact, having higher flexibility, and thus increasing the measuring range.

[0062] In one embodiment, the first object to be measured is a position reference surface, that is, Figure 3 The reference surface 2 shown; the position reference surface forms a coordinate reference for the integrated interferometric measurement head; the integrated interferometric measurement head measures the morphology of the second object being measured.

[0063] In one embodiment, Figure 3 As shown, the integrated interferometric measuring head is mounted on a rotating shaft, i.e. Figure 3 The position reference surface of the rotating head 1 shown is a circular arc surface. This embodiment uses the circular arc surface as the position reference, which can effectively eliminate the mechanical error caused by the rotating shaft when the integrated interferometric measurement head is measuring.

[0064] In one embodiment, the light is composed of at least two groups of monochromatic light. This embodiment can break through the measurement range of λ / 2 and achieve nanometer precision measurement (5-0.05nm).

[0065] In one embodiment, Figure 3 As shown, an interferometric measurement system is proposed, which is implemented based on the above-mentioned integrated interferometric measurement head, and also includes a motion component and a reference system component; the motion part drives the integrated interferometric measurement head and / or the second measured object to move, so that the measured area of ​​the second measured object is within the detection range of the object measurement head 6;

[0066] The reference system assembly includes at least one set of reference measuring heads and at least one set of coordinate reference surfaces. The reference measuring heads irradiate the coordinate reference surfaces with monochromatic light and receive the monochromatic light reflected by the coordinate reference surfaces, so that the monochromatic light reflected by the coordinate reference surfaces interferes with a portion of the monochromatic light incident on the reference measuring heads.

[0067] The first light inlet 32, the first collimating lens and the first beam splitter 30 and / or the first focusing lens 31 form a set of reference measuring heads; the position reference surfaces form a set of coordinate reference surfaces.

[0068] like Figure 3As shown, the principle of the interference measurement system of this embodiment is: multi-wavelength monochromatic light emitted by the light source 14 (the light source module includes multiple monochromatic lights, and within the visible light or infrared light wavelength range, the monochromatic lights of different wavelengths can be freely combined and output through the control system) is transmitted to the object measuring head 6 and the reference measuring head 1 4, the reference measuring head 2 11, and the reference measuring head 3 12 via the signal line 16 (the signal line includes optical fibers and wires that can transmit optical signals and electrical signals, and the schematic diagram has been simplified). A portion of the incident light is reflected back through the reference surface (i.e., the mirror surface (with very small roughness), which can be approximately regarded as an ideal surface and will not introduce significant measurement errors) in the measuring head as the reference light, and another portion of the incident light is reflected back through the object to be measured 7 or reference surface 1 2, reference surface 2 9, and reference surface 3 13 as the measuring light. The reference light and the measuring light interfere with each other after they meet in the measuring head, and the interference signal is transmitted to the detector module 15 via the signal line 16. The collected signal is initially processed by the control system and then transmitted to the computer 17, where further processing is performed to obtain the deviation data of the three-dimensional morphology of the object to be measured 7, and the data is displayed.

[0069] Object measuring head 6: used for measuring the three-dimensional shape of the object 7;

[0070] Reference measuring head 1 4, reference measuring head 2 11, reference measuring head 3 12: used to measure the displacement distance of the mechanical axis, accurately locate the position of the object measuring head 6 or the object to be measured 7 in space, and the measured data can be used to compensate for the error introduced when the mechanical axis moves.

[0071] Reference measuring head 4: Compensates for mechanical errors generated when rotating axis 5 rotates.

[0072] Reference measuring head 2 11: for compensating the mechanical error generated when the translation stage 10 moves vertically.

[0073] Reference measuring head 3 12 is used to compensate for the mechanical error generated when the translation stage 10 moves horizontally.

[0074] Error compensation: The reference measuring head measures the mechanical axis displacement distance (because the mechanical axis displacement accuracy is low, the spatial position of the object is not accurately positioned, and optical means are required to accurately locate the spatial position of the object), and subtracts or adds this value to the measurement data of the object measuring head 6 (or performs other calculations).

[0075] Among them, the object measuring head 6 and the reference measuring head 4 are an integrated interferometric measuring head. In order to complete the measurement of the morphology at different curvatures of the surface of the measured object 7, the object measuring head 6 needs to rotate around the rotating axis 5. The rotating axis 5 is a mechanical axis. During the rotation, the measurement data of the object measuring head 6 has errors due to mechanical disturbances, which need to be compensated. Therefore, the reference measuring head 4 is introduced. The object measuring head 6 and the reference measuring head 4 are coaxially integrated, and according to the Abbe principle, the measurement accuracy can be improved. In actual measurement, the distance between the reference measuring head 4 and the reference surface 2 (the reference surface 2 is fixed on the mechanical arm 3 and does not rotate) is fixed (can be calibrated in advance). When the object measuring head 6 and the reference measuring head 4 are rotated for measurement, due to the existence of mechanical disturbances, the distance between the reference measuring head 4 and the reference surface 2 will change slightly, and this change will directly affect the measurement accuracy of the system. Therefore, it is necessary to deduct the measurement data of the reference measuring head 4 from the measurement data of the object measuring head 6 to compensate for the error introduced during mechanical rotation.

[0076] Among them, the structure of the first integrated interferometric measurement head is as follows Figure 1 As shown, the incident light 22 (solid line) is first collimated by the first collimating lens 24, then reflected by the first reflector 20, and then passes through the second beam splitter 19. Part of the light is reflected back as the reference light, and part of the light is transmitted and focused by the second focusing lens 18, and then irradiated onto the object to be measured 7 and the reference surface 2 respectively, and then returns as the measuring light. The reference light meets the measuring light and interferes. The interference signal is transmitted to the detector module 15 via the signal line 16 (the interference signals of different probes and different wavelengths are detected and processed separately).

[0077] In addition, in order to complete the three-dimensional scanning of the shape of the object 7 to be measured, the object 7 to be measured needs to be moved horizontally and vertically, and this action is completed by the displacement stage 10. The displacement stage 10 has mechanical movement errors during the horizontal and vertical movement, which need to be compensated. Therefore, the reference measuring head 2 11 and the reference measuring head 3 12 are installed respectively to monitor the horizontal and vertical movement distances in real time. In addition, the object 7 to be measured needs to be rotated to complete the shape measurement, which is completed by the rotation of the rotating shaft 2 8 (the reference measuring head can also be added to monitor the errors such as runout and offset introduced during rotation in real time).

[0078] The internal structures of the reference measuring head 2 11 and the reference measuring head 3 12 are as follows: Figure 4As shown, the principle is as follows: part of the incident light 22 (solid line) is reflected by the end face of the optical fiber 28 as the reference light, and part of the light passes through the end face, meets the reference surface 2 9 (or the reference surface 3 13) after being collimated by the lens 27, and is reflected as the measuring light. The reference light meets the measuring light, and interference occurs. The interference signal is transmitted to the detector module 15 via the signal line 16. The PZT module 21 drives the optical fiber 28 to move up and down, changes the optical path difference between the reference light and the measuring light, and completes the phase modulation.

[0079] In one embodiment, Figure 2 As shown, the optical path of the integrated interferometric measuring head is further simplified, that is, the signal line 16 is placed inside the object measuring head 6 and the reference measuring head 4, the cavity 26 is filled with colloid, the signal line 16 and the second collimating lens 25 are fixed together to ensure the stability of the incident light path and the reflected light path, the PZT module 21 drives the second beam splitter 19 to move up and down, changes the optical path difference between the reference light and the measuring light, completes the phase-shifting interferometric measurement, and the cavity 26, the signal line 16, and the second collimating lens 25 are fixed.

[0080] The above is only a specific embodiment of the present invention, but the protection scope of the present invention 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 by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. An integrated interferometric measuring head, characterized in that: include: A first light inlet, used for point emission and point reception of light; A second light inlet, used for point emission and point reception of light; a first collimating lens, with a focus set at the entrance of the first light; a second collimating lens, with a focus set at the entrance of the second light; A first beam splitter, transmitting part of the outgoing light path of the first collimating lens and reflecting part of the outgoing light path, wherein at least a part of the reflected light returns to the first collimating lens along the original path, and the transmitted light is transmitted to the first object to be measured; A second beam splitter, transmitting part of the outgoing light path of the second collimating lens and reflecting part of the outgoing light path, returning at least a part of the reflected light to the optical axis of the second collimating lens along the original path, and transmitting the transmitted light to the second object to be measured; Wherein: the integrated interferometric measurement head also includes a PZT module; the PZT module drives the first beam splitter and the second beam splitter to perform linear motion in the same moving mode, and adjusts the optical path between the first beam splitter and the first collimating lens and the optical path between the second beam splitter and the second collimating lens.

2. The integrated interferometric measurement head according to claim 1, characterized in that: The integrated interferometric measurement head further includes a first focusing lens, which is disposed on a transmission outgoing light path of the first beam splitter.

3. The integrated interferometric measurement head according to claim 2, characterized in that: The integrated interferometric measurement head further includes a second focusing lens, which is disposed on a transmission outgoing light path of the second beam splitter.

4. The integrated interferometric measurement head according to claim 3, characterized in that: The optical axes of the first focusing lens and the second focusing lens coincide with each other.

5. The integrated interferometric measurement head according to claim 1, characterized in that: The integrated interferometric measurement head further includes a first reflector; the optical axis of the first collimating lens is perpendicular to the reflective surface of the first beam splitter; and the first reflector enables mutual transmission of the light between the beam splitter and the first collimating lens.

6. The integrated interferometric measuring head according to claim 1 or 5, characterized in that: The integrated interference measurement head also includes a second reflector; the optical axis of the second collimating lens is perpendicular to the reflecting surface of the second beam splitter; and the second reflector realizes the mutual transmission of the light between the beam splitter and the second collimating lens.

7. The integrated interferometric measurement head according to claim 1, characterized in that: The first measured object is a position reference surface; the position reference surface forms a coordinate reference of the integrated interferometric measurement head; the integrated interferometric measurement head measures the morphology of the second measured object.

8. The integrated interferometric measurement head according to claim 7, characterized in that: The integrated interference measurement head is installed on a rotating shaft; the position reference surface is an arc surface.

9. The integrated interferometric measurement head according to claim 1, characterized in that: The light is composed of at least two groups of monochromatic lights.

10. An interferometric measurement system, comprising the integrated interferometric measurement head according to any one of claims 1 to 9, characterized in that: The interferometric measurement system further comprises a motion component and a reference system component; the motion component drives the integrated interferometric measurement head and / or the second measured object to move, so that the measured area of ​​the second measured object is within the detection range of the measurement head; The reference system assembly includes at least one set of reference measuring heads and at least one set of coordinate reference surfaces. The reference measuring heads receive the light reflected by the coordinate reference surfaces based on the light irradiating the coordinate reference surfaces, so that the light reflected by the coordinate reference surfaces interferes with a portion of the light incident on the reference measuring heads. The first light inlet, the first collimating lens and the first beam splitter and / or the first focusing lens constitute a group of the reference measuring head; The first measured object forms a set of coordinate reference surfaces.

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