CN115046500A

CN115046500A - Parallelism measuring probe and measuring device

Info

Publication number: CN115046500A
Application number: CN202210443998.7A
Authority: CN
Inventors: 王三宏; 金少峰; 王刚奎
Original assignee: Shenzhen Sincevision Technology Co ltd
Current assignee: Shenzhen Sincevision Technology Co ltd
Priority date: 2022-04-26
Filing date: 2022-04-26
Publication date: 2022-09-13
Anticipated expiration: 2042-04-26
Also published as: CN115046500B

Abstract

The application provides a parallelism measuring probe and a measuring device. The parallelism measuring probe comprises a first lens array, the first lens array comprises a plurality of first lenses, the plurality of first lenses divide the parallel first light beams into a plurality of convergent second light beams and emit the convergent second light beams, and then the first lenses respectively receive the returned divergent third light beams and synthesize a parallel fourth light beam; the second lens array is arranged in parallel with the first lens array at intervals, and comprises a plurality of second lenses which divide the parallel first light beams into a plurality of converged fifth light beams and emit the converged fifth light beams, then respectively receive the returned diverged plurality of sixth light beams through the plurality of second lenses and synthesize parallel seventh light beams; the beam splitter is arranged corresponding to the first lens array; and the reflecting mirror is arranged corresponding to the second lens array. The application provides a depth of parallelism measuring probe can improve two object plane depth of parallelism measuring precision.

Description

Parallelism measuring probe and measuring device

Technical Field

The application relates to the field of measuring distance and measuring level, in particular to a parallelism measuring probe and a measuring device.

Background

With the development of technology, the demand of precision machining is increasing, and parallel alignment measurement is often required in the precision machining process, but because the parallel alignment measurement requires many devices, errors are easily generated in the parallel alignment measurement process.

Disclosure of Invention

In a first aspect, embodiments of the present application provide a parallelism-measuring probe, which includes:

the first lens array comprises a plurality of first lenses, the plurality of first lenses divide the parallel first light beams into a plurality of convergent second light beams and focus the convergent second light beams to a first object surface to be detected respectively, and then the first lenses respectively receive a plurality of divergent third light beams reflected or scattered back by the first object surface to be detected along an original optical path and synthesize a parallel fourth light beam;

the second lens array is arranged in parallel with the first lens array at intervals, and comprises a plurality of second lenses, the second lenses divide the parallel first light beams into a plurality of converged fifth light beams and focus the converged fifth light beams on a second object surface to be measured respectively, and then the converged fifth light beams reflected or scattered back by the second object surface to be measured along an original optical path are received by the second lenses respectively and combined into parallel seventh light beams;

the beam splitter is arranged corresponding to the first lens array and is used for reflecting the first light beam part to the first lens array and allowing the rest part of the first light beam to transmit; and

and the reflecting mirror is arranged corresponding to the second lens array and is used for reflecting the first light beam transmitted by the beam splitter to the second lens array.

The first lens array comprises at least three first lenses, and the at least three first lenses are arranged in a non-collinear arrangement; the second lens array comprises at least three second lenses, and the at least three second lenses are arranged in a non-collinear arrangement.

And the beam splitting surface of the beam splitter is perpendicular to the plane of the reflector.

The plane where the reflecting mirror is located is perpendicular to the plane where the first lens array is located, and the beam splitting surface of the beam splitter and the plane where the reflecting mirror is located form an included angle of 45 degrees.

And the beam splitting surface of the beam splitter is parallel to the plane of the reflector.

Wherein the parallelism measuring probe further comprises:

each shading sleeve corresponds to one first lens or one second lens, and the number of the shading sleeves is equal to the sum of the number of the first lenses and the number of the second lenses.

Wherein the parallelism measuring probe further comprises:

the optical fiber inserting core is used for connecting and fixing an optical fiber;

the front focus of the collimating mirror coincides with the preset position of the incident light beam position and is used for collimating the light beam output by the optical fiber into a parallel first light beam, the beam waist of the first light beam is positioned at the center of the mirror surface of the reflecting mirror, the plane of the collimating mirror is perpendicular to the plane of the first lenses, the collimating mirror is also used for converging the parallel fourth light beam into an eighth light beam and focusing the eighth light beam to the preset position of the incident light beam, and the parallel seventh light beam is converged into a ninth light beam and focusing the ninth light beam to the preset position of the incident light beam; and

and the sealed shell is used for accommodating the first lens array, the second lens array, the beam splitter, the reflector, the collimating mirror and the optical fiber ferrule.

In a second aspect, an embodiment of the present application further provides a measurement apparatus, including:

the parallelism-measuring probe of the first aspect; and

a spectral interferometer that emits a light beam to the parallelism measuring probe and receives a light beam returned from the parallelism measuring probe for optical path difference measurement.

Wherein the spectral interferometer comprises:

a wide spectrum light source for outputting a light beam;

the optical coupler is used for coupling the light beam output by the wide-spectrum light source to the parallelism measuring probe and coupling the light beam returned from the parallelism measuring probe to the spectrometer;

the spectrometer is used for receiving the light beam returned from the parallelism measuring probe and carrying out power spectrum measurement on the light beam returned from the parallelism measuring probe so as to obtain an interference power spectrum; and

and the data processor is electrically connected with the spectrograph to receive the measurement data of the interference power spectrum, obtain an optical path difference according to the interference power spectrum and judge whether the first object surface to be measured is parallel to the second object surface to be measured according to the optical path difference.

Wherein, when the parallelism measuring probe further comprises the optical fiber ferrule and the collimating mirror, the measuring device further comprises:

an optical fiber for connecting the spectral interferometer and the parallelism measuring probe to transmit a light beam between the spectral interferometer and the parallelism measuring probe;

the optical coupler includes:

the optical fiber circulator is provided with a first interface, a second interface and a third interface which are circumferentially arranged at intervals, the first interface is connected to the wide-spectrum light source and used for receiving light beams output by the wide-spectrum light source, the optical fiber circulator is used for transmitting the light beams output by the wide-spectrum light source to the second interface and transmitting the light beams to the parallelism measuring probe through the second interface, the second interface is also used for receiving the light beams returned from the parallelism measuring probe, and the optical fiber circulator is used for transmitting the received light beams to the spectrometer through the third interface.

The application provides a depth of parallelism measuring probe, depth of parallelism measuring probe includes a plurality of first lenses, a plurality of first lenses divide into the first light beam of parallel and converge a plurality of second light beams and focus on first object plane of awaiting measuring respectively, then via a plurality of first lenses receive respectively by first object plane of awaiting measuring is along the divergent a plurality of third light beams of original light path reflection or scattering back and synthesize parallel fourth light beam again. The second lens array is arranged in parallel with the first lens array at intervals, the second lens array comprises a plurality of second lenses, the plurality of second lenses divide the parallel first light beams into a plurality of converged fifth light beams and focus the converged fifth light beams to a second object surface to be measured respectively, and then the converged fifth light beams are received by the plurality of second lenses respectively and are reflected or scattered back by the second object surface to be measured along an original optical path to synthesize parallel seventh light beams. The beam splitter is arranged corresponding to the first lens array and is used for partially reflecting the first light beam to the first lens array and allowing the rest of the first light beam to transmit. The reflecting mirror is arranged corresponding to the second lens array and used for reflecting the first light beam transmitted by the beam splitter to the second lens array. The parallelism measuring probe has few devices, and can avoid optical axis drift, thereby reducing measuring errors. In addition, the parallelism measuring probe does not contain an electromagnetic device, so that the parallelism measuring probe can avoid electromagnetic interference on a measuring result, and the measuring precision is improved. Therefore, the parallelism measuring probe provided by the application can improve the measurement precision of the parallelism of two object planes.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

Fig. 1 is a schematic structural diagram of a parallelism measuring probe according to an embodiment of the present application.

Fig. 2 is a schematic structural diagram of a first lens array in the parallelism measuring probe provided in the embodiment of fig. 1.

Fig. 3 is a schematic structural diagram of a second lens array in the parallelism measuring probe provided in the embodiment of fig. 1.

Fig. 4 is a schematic diagram of an embodiment of a beam splitter and a mirror in the parallelism measuring probe according to the embodiment of fig. 1.

Fig. 5 is a schematic diagram of an arrangement of another embodiment of a beam splitter and a mirror in the parallelism measuring probe provided in the embodiment of fig. 1.

FIG. 6 is a schematic diagram of an arrangement of a beam splitter and a mirror in the parallelism measuring probe according to the embodiment of FIG. 1 according to another embodiment

Fig. 7 is a schematic structural diagram of a parallelism probe according to yet another embodiment of the present application.

Fig. 8 is a schematic structural diagram of a parallelism-measuring probe according to yet another embodiment of the present application.

Fig. 9 is a schematic connection diagram of a measurement apparatus according to an embodiment of the present disclosure.

Fig. 10 is a schematic structural diagram of an embodiment of a spectral interferometer in the measuring apparatus provided in the embodiment of fig. 9.

Fig. 11 is a schematic diagram of a working process of the measuring device provided in the embodiment of fig. 10 for measurement.

Fig. 12 is a schematic structural diagram of a spectral interferometer in the measuring apparatus provided in the embodiment of fig. 9 in another embodiment.

Reference numbers: a measuring device 1; a parallelism measuring probe 10; a spectral interferometer 20; an optical fiber 30; a first lens array 110; a second lens array 120; a beam splitter 130; a mirror 140; a light shielding sleeve 150; an optical fiber ferrule 160; a collimating mirror 170; a hermetic case 180; a broad spectrum light source 210; an optical coupler 220; a spectrometer 230; a data processor 240; a first lens 111; a second lens 121; a fiber circulator 221; a first interface 2211; a second interface 2212; a third interface 2213; a first light beam L1; a second light beam L2; the third light beam L3; the fourth light beam L4; the fifth light beam L5; the sixth light beam L6; the seventh light beam L7; the eighth light beam L8; the ninth light beam L9; a first object plane W1; and a second object plane W2.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments in the present application without any inventive step are within the scope of protection of the present application.

The terms "first," "second," and the like in the description and claims of the present application and in the above-described drawings are used for distinguishing between different objects and not for describing a particular order. Furthermore, the terms "include" and "have," as well as any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, system, article, or apparatus that comprises a list of steps or elements is not limited to only those steps or elements listed, but may alternatively include other steps or elements not listed, or inherent to such process, method, article, or apparatus.

Reference herein to "an embodiment" or "an implementation" means that a particular feature, structure, or characteristic described in connection with the embodiment or implementation can be included in at least one embodiment of the present application. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. It is explicitly and implicitly understood by one skilled in the art that the embodiments described herein may be combined with other embodiments.

The present embodiment provides a parallelism measuring probe 10. Referring to fig. 1, fig. 2 and fig. 3 together, fig. 1 is a schematic structural diagram of a parallelism measuring probe according to an embodiment of the present disclosure; FIG. 2 is a schematic diagram of a first lens array in the parallelism measuring probe provided in the embodiment of FIG. 1; fig. 3 is a schematic structural diagram of a second lens array in the parallelism measuring probe provided in the embodiment of fig. 1. In the present embodiment, the parallelism measuring probe 10 includes a first lens array 110, a second lens array 120, a beam splitter 130, and a mirror 140. The first lens array 110 includes a plurality of first lenses 111, and the plurality of first lenses 111 divide the parallel first light beams L1 into a plurality of converging second light beams L2 and focus the plurality of converging second light beams L2 onto the first object plane W1 respectively, and then receive a plurality of diverging third light beams L3 reflected or scattered back by the first object plane W1 along an original optical path respectively via the plurality of first lenses 111 and combine into a parallel fourth light beam L4. The second lens array 120 is disposed in parallel with the first lens array 110 at an interval, the second lens array 120 includes a plurality of second lenses 121, the plurality of second lenses 121 divide the parallel first light beams L1 into a plurality of converging fifth light beams L5, and focus the light beams onto the second object plane W2 respectively, and then receive the diverging sixth light beams L6 reflected or scattered back along the original optical path by the second object plane W2 respectively via the plurality of second lenses 121 and combine the light beams into a parallel seventh light beam L7. The beam splitter 130 is disposed corresponding to the first lens array 110 and is used for partially reflecting the first light beam L1 to the first lens array 110, and allowing the rest of the first light beam L1 to transmit. The reflecting mirror 140 is disposed corresponding to the second lens array 120 and is used for reflecting the first light beam L1 transmitted by the beam splitter 130 to the second lens array 120.

In the present embodiment, the parallelism measuring probe 10 is used for optical measurement of parallel alignment, and specifically, the parallelism measuring probe 10 is used for measuring whether the first object plane W1 and the second object plane W2 are parallel.

In the present embodiment, the first lens array 110 includes a plurality of first lenses 111. The plurality of first lenses 111 are used for converting the parallel light beams into convergent light beams to be emitted, and converting the reversely transmitted divergent light beams into parallel light beams to be received back. Therefore, the one first lens 111 corresponds to one of the second light beams L2 and one of the third light beams L3. Specifically, in one embodiment, the first lens array 110 is an integral microlens array, the first lenses 111 are microlenses, and an opaque light-absorbing material is disposed between the first lenses 111. In another embodiment, the second lens array 120 is prepared by mounting the first lenses 111 to a carrier having a plurality of mounting holes, where other areas of the mounting holes are prepared by light-absorbing materials.

In the present embodiment, the second lens array 120 includes a plurality of second lenses 121. The plurality of second lenses 121 are used for converting the parallel light beams into convergent light beams to be emitted, and converting the reversely transmitted divergent light beams into parallel light beams to be received back. Therefore, the one second lens 121 corresponds to one of the fifth light beams L5 and one of the sixth light beams L6. Specifically, in one embodiment, the second lens array 120 is an integral microlens array, the second lenses 121 are microlenses, and an opaque light-absorbing material is disposed between the second lenses 121. In another embodiment, the second lens array 120 is prepared by mounting the second lenses 121 on a carrier having a plurality of mounting holes, where other areas of the mounting holes are prepared by light-absorbing materials.

In this embodiment, the beam splitter 130 is configured to reflect a portion of the first light beam L1 to the first lens array 110 and a portion of the fourth light beam L4 from the first lens array 110. The beam splitter 130 is also used to transmit another part of the first light beam L1 to the second lens array 120 and transmit a part of the seventh light beam L7 from the second lens array 120.

In the present embodiment, the reflecting mirror 140 is used for changing the transmission directions of the first light beam L1 and the seventh light beam L7. Specifically, the reflecting mirror 140 is configured to reflect the first light beam L1 transmitted by the beam splitter 130 to the second lens array 120, and reflect the seventh light beam L7 from the second lens array 120 to the beam splitter 130.

In the present embodiment, the plurality of second lenses 121 are disposed parallel to or coplanar with the plurality of first lenses 111. Therefore, it is only necessary to measure whether the first object plane W1 and the first lens 111 are parallel or not and whether the second object plane W2 and the second lens 121 are parallel or not, so as to measure whether the first object plane W1 and the second object plane W2 are parallel or not.

In the present embodiment, the plurality of first lenses 111 divide part of the parallel first light beams L1 into the plurality of converging second light beams L2 and exit through the plurality of first lenses 111. The plurality of first lenses 111 are configured to receive the converging plurality of second light beams L2 irradiated to the first object plane W1 to reflect or backscatter the diverging plurality of third light beams L3, and synthesize a parallel fourth light beam L4, and determine whether the first object plane W1 is parallel to the plurality of first lenses 111 by measuring the fourth light beam L4. The plurality of second lenses 121 divide the other part of the parallel first light flux L1 into a plurality of converging fifth light fluxes L5 to exit. The plurality of second lenses 121 are configured to receive the plurality of converging fifth light beams L5 and irradiate the second object plane W2 to reflect or backscatter the plurality of diverging sixth light beams L6, and synthesize a parallel seventh light beam L7, and determine whether the second object plane W2 is parallel to the plurality of second lenses 121 by measuring the seventh light beam L7. When the first object plane W1 is parallel to the first lenses 111 and the second object plane W2 is parallel to the second lenses 121, the first object plane W1 is parallel to the second object plane W2.

In the present embodiment, by blocking one of the first lens array 110 and the second lens array 120, one of the first object plane W1 and the second object plane W2 is aligned in parallel, and then the blocking is removed to align the other one of the first object plane W1 and the second object plane W2 in parallel. Specifically, to first block the second lens array 120 for illustration, the parallel first light beam L1 is partially reflected to the first lens array 110 via the beam splitter 130, and exits the converged second light beam L2 via the plurality of first lenses 111, the converged second light beam L2 is reflected or backscattered at the first object plane W1 to form the diverged third light beam L3, the diverged third light beam L3 is received by the plurality of first lenses 111 and combined into the parallel fourth light beam L4, the fourth light beam L4 is reflected to the spectral interferometer 20 via the beam splitter 130, so that the spectral interferometer 20 calculates an optical path difference according to the internal interference of the fourth light beam L4, when the optical path difference tends to zero, the first object plane W1 is parallel to the plurality of first lenses 111, if the optical path difference has a non-zero value, the parallelism-measuring probe is adjusted in posture until the optical path difference approaches zero, so that the first object plane W1 is parallel to the first lenses 111. By removing the shielding of the second lens array 120, the parallel alignment measurement of the second object plane W2 can be performed. The parallel first light beam L1 is partially reflected to the first lens array 110 via the beam splitter 130 and exits the converged plurality of second light beams L2 via the plurality of first lenses 111, and the other part of the parallel first light beam L1 passes through the beam splitter 130 and is reflected to the second lens array 120 via the mirror 140 and exits the converged plurality of fifth light beams L5 via the plurality of second lenses 121. The converged plurality of second light beams L2 are reflected or backscattered at the first object plane W1 to form the divergent plurality of third light beams L3, and the divergent plurality of third light beams L3 are received by the plurality of first lenses 111 and combined into the parallel fourth light beams L4. The converged fifth light beams L5 irradiate the second object plane W2 to be reflected or backscattered to form diverging sixth light beams L6, and the diverging sixth light beams L6 are received by the second lenses 121 and combined into the parallel seventh light beams L7. Both the fourth light beam L4 and the seventh light beam L7 enter the spectral interferometer 20. In one embodiment, the difference between the distance from the beam splitter 130 to the first lens array 110 and the distance to the second lens array 120 in the beam transmission direction is larger than the measurement range of the spectral interferometer 20, and the fourth light beam L4 and the seventh light beam L7 interfere with each other, but the fourth light beam L4 and the seventh light beam L7 do not interfere with each other. Therefore, when the optical path difference has a non-zero value, the second object plane W2 is not parallel to the plurality of second lenses 121, i.e., the second object plane W2 is not parallel to the first object plane W1. The second object plane W2 can be made parallel to the first object plane W1 by adjusting the posture of the second object plane W2 or adjusting the postures of the parallelism measuring probe 10 and the first object plane W1 as a whole until the optical path difference approaches zero. In another embodiment, the difference between the distance from the beam splitter 130 to the first lens array 110 and the distance to the second lens array 120 in the beam transmission direction is less than or equal to the measurement range of the spectral interferometer 20, and in addition to the interference occurring inside the fourth light beam L4 and the interference occurring inside the seventh light beam L7, the interference also occurs between the fourth light beam L4 and the seventh light beam L7. If the distance from the beam splitter 130 to the first lens array 110 in the beam transmission direction is not equal to the distance from the beam splitter 130 to the second lens array 120, the second object plane W2 is parallel to the plurality of second lenses 121, that is, the second object plane W2 is parallel to the first object plane W1, only when the optical path difference has only one fixed non-zero value, that is, the difference between the distance from the beam splitter 130 to the first lens array 110 in the beam transmission direction and the distance to the second lens array 120 is 2 times larger than the difference between the distances from the beam splitter 130 to the first lens array 110 and the second lens array 120. If the distance from the beam splitter 130 to the first lens array 110 in the beam transmission direction is equal to the distance from the second lens array 120, when the optical path difference tends to zero, the second object plane W2 is parallel to the first object plane W1.

The application provides a parallelism measuring probe 10, the parallelism measuring probe 10 includes a plurality of first lenses 111, the plurality of first lenses 111 divide parallel first light beams L1 into a plurality of convergent second light beams L2 and focus respectively to a first object plane W1, then via the plurality of first lenses 111 respectively receive a plurality of divergent third light beams L3 reflected or scattered back by the first object plane W1 along an original optical path again and combine into a parallel fourth light beam L4. The second lens array 120 is disposed in parallel with the first lens array 110 at an interval, the second lens array 120 includes a plurality of second lenses 121, the plurality of second lenses 121 divide the parallel first light beams L1 into a plurality of converging fifth light beams L5, and focus the light beams onto the second object plane W2 respectively, and then receive the diverging sixth light beams L6 reflected or scattered back along the original optical path by the second object plane W2 respectively via the plurality of second lenses 121 and combine the light beams into a parallel seventh light beam L7. The beam splitter 130 is disposed corresponding to the first lens array 110 and is used for partially reflecting the first light beam L1 to the first lens array 110, and allowing the rest of the first light beam L1 to transmit. The reflecting mirror 140 is disposed corresponding to the second lens array 120 and is used for reflecting the first light beam L1 transmitted by the beam splitter 130 to the second lens array 120. The parallelism measuring probe 10 has few devices, and can avoid optical axis drift, thereby reducing measuring errors. In addition, the parallelism measuring probe 10 does not include an electromagnetic device, so the parallelism measuring probe 10 can avoid electromagnetic interference with the measurement result, thereby improving the measurement accuracy. Therefore, the parallelism measuring probe 10 provided by the application can improve the measurement precision of the parallelism of two object planes.

Referring to fig. 2 and fig. 3 again, in the present embodiment, the first lens array 110 includes at least three first lenses 111, and the at least three first lenses 111 are arranged in a non-collinear manner. The second lens array 120 includes at least three second lenses 121, and the at least three second lenses 121 are arranged in a non-collinear arrangement.

In this embodiment, the first lens array 110 includes at least three first lenses 111, and the at least three first lenses 111 are arranged in a non-collinear arrangement. Since at least three non-collinear arrangement positions, that is, at least three second light beams L2, are required for measuring whether the first object plane W1 is parallel to the first lens 111, at least three first lenses 111 are required for the first lens array 110, and at least three first lenses 111 are arranged in a non-collinear arrangement.

In this embodiment, the second lens array 120 includes at least three second lenses 121, and at least three second lenses 121 are arranged in a non-collinear arrangement. Since at least three non-collinear arrangement positions, that is, at least three fifth light beams L5, are required for measuring whether the second object plane W2 is parallel to the second lens 121, the second lens array 120 requires at least three second lenses 121, and at least three second lenses 121 are arranged in a non-collinear arrangement.

In addition, in the present embodiment (please refer to fig. 1), since the sizes of the first lens array 110 and the second lens array 120 can be designed to be small, the size of the parallelism measuring probe 10 can be designed to be small, for example, the outer diameter d0 of the parallelism measuring probe 10 can be, but not limited to, 100 μm or 2mm, so that the parallelism measuring probe 10 can be applied to a narrower space for parallelism measurement. It should be noted that, in the present embodiment, the size of the parallelism measuring probe 10 is not limited, the size of the parallelism measuring probe 10 is designed according to a specific measuring environment, and the size of the parallelism measuring probe 10 is not limited to a small size, but may be designed to a large size, for example, the outer diameter d0 of the parallelism measuring probe 10 may be, but not limited to, 10mm, 20mm, or 30 mm.

In the present embodiment, the cross-sectional shape of the plurality of first lenses 111 in the direction perpendicular to the first direction may be, but is not limited to, a circle, a rectangle, a polygon, or the like. The sectional shapes of the plurality of second lenses 121 in the direction perpendicular to the second direction may be, but are not limited to, circular, rectangular, polygonal, or the like. Wherein the first direction is a direction in which the first light beam L1 is incident on the first lens array 110, and the second direction is a direction in which the first light beam L1 is incident on the second lens array 120.

In this embodiment, the at least three first lenses 111 have the same optical performance, the same aperture, and the same focal length. Wherein, the at least three first lenses 111 have longer focal depths, which can reduce the measurement error. The at least three second lenses 121 have the same optical performance, the same aperture, and the same focal length. Wherein, the at least three second lenses 121 have longer focal depths, which can reduce the measurement error.

Referring to fig. 4, fig. 4 is a schematic diagram illustrating an embodiment of a beam splitter and a mirror in the parallelism measuring probe according to the embodiment of fig. 1. In this embodiment, the beam splitting surface of the beam splitter 130 is perpendicular to the plane of the mirror 140.

In this embodiment, the beam splitting surface of the beam splitter 130 is perpendicular to the plane of the reflecting mirror 140, that is, the parallelism measuring probe 10 is used to measure the parallelism of the first object plane W1 and the second object plane W2 on both sides of the parallelism measuring probe 10. Specifically, the beam splitter 130 is configured to reflect a part of the first light beam L1 to the first lens array 110, so as to be split into a plurality of second light beams L2 by the plurality of first lenses 111 and exit through the plurality of first lenses 111. Another part of the first light beam L1 passes through the beam splitter 130 and is reflected to the second lens array 120 by the mirror 140, so as to be split into a plurality of fifth light beams L5 by the plurality of second lenses 121 and exit through the plurality of second lenses 121. The emitting direction of the fifth light beams L5 is opposite to the emitting direction of the second light beam L2, so that the parallelism measuring probe 10 can measure whether the first object plane W1 and the second object plane W2 on both sides of the parallelism measuring probe 10 are parallel. It should be noted that the beam splitting surface of the beam splitter 130 refers to a structure of the beam splitter 130 that can achieve light beam transmission and light beam reflection.

Referring to fig. 5, fig. 5 is a schematic diagram illustrating an arrangement of a beam splitter and a mirror in another embodiment of the parallelism measuring probe according to the embodiment of fig. 1. In this embodiment, the plane of the reflecting mirror 140 is perpendicular to the plane of the first lens array 110, and the beam splitting surface of the beam splitter 130 forms an included angle of 45 ° with the plane of the reflecting mirror 140.

In the present embodiment, the beam splitter 130 is configured to reflect a part of the first light beam L1 to the first lens array 110, so as to be split into a plurality of second light beams L2 by the plurality of first lenses 111 and exit through the plurality of first lenses 111. The other part of the first light beam L1 passes through the beam splitter 130 and is reflected to the beam splitter 130 by the mirror 140, wherein part of the first light beam L1 is reflected to the second lens array 120 by the beam splitter 130 to be split into a plurality of fifth light beams L5 by the plurality of second lenses 121 and exit through the plurality of second lenses 121, and the other part of the first light beam L1 is transmitted by the beam splitter 130. The emitting direction of the fifth light beams L5 is opposite to the emitting direction of the second light beam L2, so that the parallelism measuring probe 10 can measure whether the first object plane W1 and the second object plane W2 on both sides of the parallelism measuring probe 10 are parallel.

It should be noted that the reflecting mirror 140 may be a mirror surface of the reflecting mirror 140 to implement light beam reflection, or may be a reflecting film coated to implement light beam reflection. The beam splitting surface of the beam splitter 130 refers to a structure in which the beam splitter 130 can transmit and reflect light beams.

It should be noted that, when the difference between the distance from the beam splitter 130 to the mirror 140 in the transmission direction and the distance from the beam splitter 130 to the first object plane W1 in the transmission direction is required to be greater than the measurement range of the spectral interferometer 20, and the difference between the distance from the beam splitter 130 to the mirror 140 in the transmission direction and the distance from the beam splitter 130 to the second object plane W2 in the transmission direction is required to be greater than the measurement range of the spectral interferometer 20, the part of the first light beam L1 that passes through the beam splitter 130 after being reflected by the mirror 140 does not interfere with the fourth light beam L4, nor with the seventh light beam L7.

Referring to fig. 6, fig. 6 is a schematic diagram illustrating an arrangement of a beam splitter and a mirror in the parallelism measuring probe according to the embodiment of fig. 1 according to another embodiment. In this embodiment, the beam splitting surface of the beam splitter 130 is parallel to the plane of the mirror 140.

In this embodiment, the beam splitting surface of the beam splitter 130 is parallel to the reflecting mirror 140, that is, the parallelism measuring probe 10 is used to measure the first object plane W1 and the second object plane W2 on the same side of the parallelism measuring probe 10. Specifically, the beam splitter 130 is configured to reflect a portion of the first light beam L1 to the first lens array 110, so as to split the portion of the first light beam L1 reflected by the beam splitter 130 into a plurality of second light beams L2 through the plurality of first lenses 111 and exit through the plurality of first lenses 111. Another part of the first light beam L1 passes through the beam splitter 130 and is reflected by the mirror 140 to the second lens array 120, so as to be split into a plurality of fifth light beams L5 by the plurality of second lenses 121 and exit through the plurality of second lenses 121. The emitting direction of the fifth light beams L5 is the same as the emitting direction of the second light beam L2, so that the parallelism measuring probe 10 can measure the first object plane W1 and the second object plane W2 which are on the same side of the parallelism measuring probe 10, and are parallel or coplanar. The beam splitting surface of the beam splitter 130 refers to a structure of the beam splitter 130 that can achieve beam transmission and beam reflection.

Referring to fig. 7, fig. 7 is a schematic structural diagram of a parallelism probe according to another embodiment of the present application. In this embodiment, the parallelism-measuring probe 10 further comprises a plurality of light-shielding sleeves 150. Each of the light shielding sleeves 150 is disposed corresponding to one of the first lenses 111 or one of the second lenses 121, and the number of the light shielding sleeves 150 is equal to the sum of the numbers of the first lenses 111 and the second lenses 121.

In the present embodiment, each of the first lenses 111 is provided corresponding to one of the light shielding sleeves 150, and the light shielding sleeve 150 provided corresponding to the first lens 111 has an opening in a direction toward the first object plane W1, so that a light beam can exit to the first object plane W1 through the opening. The light shielding sleeve 150 can prevent the light beam emitted through the first lens 111 from being reflected or backscattered on the first object plane W1 to enter other first lenses 111 disposed adjacently. Further, a dimension of the light shielding sleeve 150 in a direction in which the first lens 111 is directed toward the light shielding sleeve 150 is smaller than a focal length of the first lens 111.

In this embodiment, each of the second lenses 121 is disposed corresponding to one of the light shielding sleeves 150, and the light shielding sleeve 150 disposed corresponding to the second lens 121 has an opening in a direction toward the second object plane W2, so that the light beam can exit to the second object plane W2 through the opening. The light shielding sleeve 150 can prevent the light beam emitted from the second lens 121 from being reflected or backscattered on the second object plane W2 and entering other second lenses 121 disposed adjacently. Further, the size of the light shielding sleeve 150 in the direction in which the second lens 121 is directed to the light shielding sleeve 150 is smaller than the focal length of the second lens 121.

Referring to fig. 8, fig. 8 is a schematic structural diagram of a parallelism measuring probe according to another embodiment of the present application. In the present embodiment, the parallelism measuring probe 10 further includes a fiber stub 160, a collimator lens 170, and a seal housing 180. The fiber stub 160 is used to connect and fix the optical fiber 30. The front focus of the collimating mirror 170 coincides with a preset position of light beam incidence, and is configured to collimate the light beam output by the optical fiber 30 into a parallel first light beam L1, a beam waist of the first light beam L1 is located at the center of the mirror surface of the reflecting mirror 140, a plane of the collimating mirror 170 is perpendicular to a plane of the first lenses 111, the collimating mirror 170 is further configured to converge the parallel fourth light beam L4 into an eighth light beam L8 and focus the eighth light beam to the preset position of light beam incidence, and converge the parallel seventh light beam L7 into a ninth light beam L9 and focus the ninth light beam to the preset position of light beam incidence. The sealed housing 180 is used for accommodating the first lens array 110, the second lens array 120, the beam splitter 130, the reflector 140, the collimator 170, and the fiber stub 160.

In this embodiment, the optical fiber ferrule 160 is disposed at one side of the collimating mirror 170, and an end surface of the optical fiber 30, from which the first light beam L1 exits, is located at a focal point of the collimating mirror 170, that is, a preset incident light point of the light beam, which is beneficial for the parallel fourth light beam L4 and the parallel seventh light beam L7 to converge into the eighth light beam L8 and the ninth light beam L9 via the collimating mirror 170 and couple into the optical fiber 30 to improve light energy received by the optical fiber 30. The first lenses 111 and the second lenses 121 are disposed on the other side of the collimator 170 to receive the parallel light collimated by the collimator 170. Specifically, after the first light beam L1 is collimated by the collimator lens 170, the parallelism of the first light beam L1 transmitted to the first lenses 111 and the second lenses 121 is improved.

In this embodiment, the sealed housing 180 may be, but not limited to, an integrated type or a split type. In one embodiment, the sealed housing 180 integrally houses the first lens array 110, the second lens array 120, the beam splitter 130, the mirror 140, the collimating mirror 170, and the fiber stub 160. In another embodiment, the sealing housing 180 is a split structure, and the sealing housing 180 receives one or more of the first lens array 110, the second lens array 120, the beam splitter 130, the reflector 140, the collimator 170, and the fiber stub 160 through a plurality of sub sealing housings 180, and then assembles the plurality of sub sealing housings 180 to form the parallelism measuring probe 10. The first lens array 110, the second lens array 120, the beam splitter 130, the reflector 140, the collimator 170, and the fiber stub 160 can be configured in various specifications, so that the parallelism measuring probe 10 can adapt to various application environments.

The embodiment of the application also applies for a measuring device 1. Referring to fig. 9, fig. 9 is a schematic connection diagram of a measurement apparatus according to an embodiment of the present disclosure. In the present embodiment, the measuring apparatus 1 includes a spectral interferometer 20 and a parallelism measuring probe 10 according to any one of the embodiments described above. The spectral interferometer 20 sends a light beam to the parallelism measuring probe and receives a light beam returned from the parallelism measuring probe for optical path difference measurement.

In the present embodiment, the parallelism measuring probe 10 is connected to the spectral interferometer 20, the parallelism measuring probe 10 is configured to emit the light beam from the spectral interferometer 20 to the first object plane W1 and the second object plane W2, respectively, and the parallelism measuring probe 10 is further configured to receive the light beams returning from the first object plane W1 and the second object plane W2 and transmit them together to the spectral interferometer 20.

In the present embodiment, the measuring apparatus 1 is used for optical measurement of parallel alignment, and specifically, the measuring apparatus 1 is used for measuring whether the first object plane W1 and the second object plane W2 are parallel.

Specifically, referring to fig. 10 and 11, fig. 10 is a schematic structural diagram of an embodiment of a spectral interferometer in the measuring apparatus provided in the embodiment of fig. 9; fig. 11 is a schematic view of the measuring device provided in the embodiment of fig. 10 in a working process of measurement. The spectral interferometer 20 includes: a broad spectrum light source 210, an optical coupler 220, a spectrometer 230, and a data processor 240. The broad spectrum light source 210 is for outputting a light beam. The optical coupler 220 is used for coupling the light beam output by the broad spectrum light source 210 to the parallelism measuring probe 10 and for coupling the light beam returning from the parallelism measuring probe 10 to the spectrometer 230. The spectrometer 230 is used for receiving the light beam returned from the parallelism measuring probe 10 and performing power spectrum measurement to obtain an interference power spectrum. The data processor 240 is electrically connected to the spectrometer 230 to receive the measurement data of the interference power spectrum, obtain an optical path difference according to the interference power spectrum, and determine whether the first object plane W1 and the second object plane W2 are parallel or not according to the optical path difference.

In the present embodiment, the operation process of performing measurement by using the measurement apparatus 1 may include, but is not limited to: s1, S2, S3, S4 and S5. Next, steps S1, S2, S3, S4, and S5 are described in detail.

S1, providing the parallelism measuring probe 10, disposing the first lens array 110 toward the first object plane W1, and disposing the second lens array 120 toward the second object plane W2.

In the present embodiment, the first lens array 110 is disposed toward the first object plane W1, and the first object plane W1 is disposed near the beam waist of the outgoing light beams from the first lenses 111, so that the second light beams L2 can be better incident on the first object plane W1. The second object plane W2 is disposed toward the second lens array 120, and the second object plane W2 is disposed near beam waists of the emergent light beams of the second lenses 121, so that the third light beams L3 can be better incident on the second object plane W2.

S2, outputting a light beam by the broad spectrum light source 210, the optical coupler 220 coupling the light beam to the parallelism measuring probe 10, blocking one of the first lens array 110 and the second lens array 120, and receiving a returned light beam by the parallelism measuring probe 10.

In this embodiment, the broad spectrum light source 210 is configured to output low coherence light, which has good distance measurement characteristics. Therefore, the interference information of the backscattered light (or surface reflected light) of two different parts of the sample to be measured can be extracted to determine the related physical quantity of the sample to be measured, and the method has higher sensitivity and precision and is suitable for non-contact nondestructive measurement.

In this embodiment, when the parallelism measuring probe 10 does not include the collimator lens 170, the light beam output by the wide-spectrum light source 210 is the parallel first light beam L1. When the parallelism measuring probe 10 includes the collimator lens 170, the light beam output by the wide-spectrum light source 210 is a diverging light beam, and the collimator lens 170 collimates the light beam output by the wide-spectrum light source 210 into a parallel first light beam L1.

In this embodiment, by blocking one of the first lens array 110 and the second lens array 120, one of the first object plane W1 and the second object plane W2 is aligned in parallel, and then the blocking is removed to align the other of the first lens array 110 and the second lens array 120 in parallel. Specifically, for illustration by first blocking the second lens array 120, a part of the parallel first light beam L1 is reflected to the first lens array 110 via the beam splitter 130, and exits the converged second light beam L2 via the plurality of first lenses 111, the converged second light beam L2 is reflected or backscattered on the first object plane W1 to form a divergent third light beam L3, and the divergent third light beam L3 is incident to the parallelism measuring probe 10 through the plurality of first lenses 111 and combined into the parallel fourth light beam L4.

S3, receiving the returned light beam by the spectrometer 230, and performing power spectrum measurement to obtain an interference power spectrum.

In this embodiment, when the parallelism-measuring probe 10 does not include the collimator mirror 170, the fourth light beam L4 is coupled to the spectrometer 230 via the optical coupler 220, so that the spectrometer 230 performs power spectrum measurement on the fourth light beam L4 to obtain an interference power spectrum. When the parallelism-measuring probe 10 includes the collimator lens 170, the fourth light beam L4 is converged into the eighth light beam L8 by the collimator lens 170 and transmitted to the optical coupler 220, and the optical coupler 220 couples the eighth light beam L8 to the spectrometer 230, so that the spectrometer 230 performs power spectrum measurement on the eighth light beam L8 to obtain an interference power spectrum.

S4, receiving the interference power spectrum through the data processor 240, calculating the optical path difference, and adjusting the optical path difference to zero.

In the present embodiment, the data processor 240 receives the interference power spectrum to calculate the optical path difference, and when the optical path difference approaches zero, it indicates that the first object plane W1 is parallel to the plurality of first lenses 111. When the optical path difference is a non-zero value, the first object plane W1 is adjusted until the optical path difference approaches zero.

S5, withdrawing the shielding object, and measuring the parallelism of the first object plane W1 and the second object plane W2.

In this embodiment, by removing the block on the second lens array 120, the parallel alignment measurement can be performed on the second object plane W2. A part of the parallel first light beams L1 is reflected to the first lens array 110 via the beam splitter 130 and exits the converged plurality of second light beams L2 via the plurality of first lenses 111, and the other part of the parallel first light beams L1 is transmitted through the beam splitter 130 to the second lens array 120 and exits the converged plurality of fifth light beams L5 via the plurality of second lenses 121. The converged second light flux L2 is reflected or backscattered on the first object plane W1 to form a divergent third light flux L3, and the divergent third light flux L3 is incident on the parallelism measuring probe 10 through the first lenses 111 and is combined into the parallel fourth light flux L4. The converged fifth light beam L5 irradiates the second object plane W2 to be reflected or backscattered to form a divergent sixth light beam L6, and the divergent sixth light beam L6 is incident on the parallelism measuring probe 10 through the second lenses 121 and is combined into the parallel seventh light beam L7. When the parallelism-measuring probe 10 does not include the collimator mirror 170, the spectrometer 230 receives the fourth light beam L4 and the seventh light beam L7. When the parallelism measuring probe 10 includes the collimator lens 170, the fourth light beam L4 is converged into the eighth light beam L8 via the collimator lens 170 and transmitted to the optical coupler 220, and the seventh light beam L7 is converged into the ninth light beam L9 via the collimator lens 170 and transmitted to the optical coupler 220. The spectrometer 230 receives the eighth light beam L8 and the ninth light beam L9.

Specifically, the optical coupler 220 couples the fourth light beam L4 and the seventh light beam L7 to the spectrometer 230 as an example. In one embodiment, the difference between the distance from the beam splitter 130 to the first lens array 110 and the distance to the second lens array 120 in the beam transmission direction is larger than the measurement range of the spectral interferometer 20, interference occurs inside the fourth light beam L4 and inside the seventh light beam L7, but interference does not occur between the fourth light beam L4 and the seventh light beam L7. Therefore, when the optical path difference has at least one non-zero value, the second object plane W2 is not parallel to the plurality of second lenses 121, i.e., the second object plane W2 is not parallel to the first object plane W1. By adjusting the second object plane W2 until the optical path difference approaches zero, the second object plane W2 can be made parallel to the first object plane W1. In another embodiment, the difference between the distance from the beam splitter 130 to the first lens array 110 and the distance to the second lens array 120 in the beam transmission direction is less than or equal to the measurement range of the spectral interferometer 20, and in addition to the interference inside the fourth light beam L4 and the seventh light beam L7, the interference between the fourth light beam L4 and the seventh light beam L7 occurs. If the distance from the beam splitter 130 to the first lens array 110 in the beam transmission direction is not equal to the distance from the beam splitter 130 to the second lens array 120, when the optical path difference has only one fixed non-zero value, that is, the difference between the distance from the beam splitter 130 to the first lens array 110 in the beam transmission direction and the distance to the second lens array 120 is 2 times, the second object plane W2 is parallel to the plurality of second lenses 121, that is, the second object plane W2 is parallel to the first object plane W1. If the distance from the beam splitter 130 to the first lens array 110 in the beam transmission direction is equal to the distance from the second lens array 120, when the optical path difference tends to zero, the second object plane W2 is parallel to the first object plane W1.

Referring to fig. 12, fig. 12 is a schematic structural diagram of a spectral interferometer in the measuring apparatus provided in the embodiment of fig. 9 in another embodiment. When the parallelism measuring probe 10 further includes the optical fiber ferrule 160 and the collimator 170, the measuring apparatus 1 further includes an optical fiber 30. The optical fiber 30 is used to connect the spectral interferometer 20 and the parallelism measuring probe 10 to transmit a light beam between the spectral interferometer 20 and the parallelism measuring probe 10. The optical coupler 220 includes a fiber optic circulator 221. The optical fiber circulator 221 has a first interface 2211, a second interface 2212 and a third interface 2213 arranged at intervals in the circumferential direction, the first interface 2211 is connected to the wide-spectrum light source 210 and is used for receiving the light beam output by the wide-spectrum light source 210, the optical fiber circulator 221 is used for transmitting the light beam output by the wide-spectrum light source 210 to the second interface 2212 and transmitting the light beam to the parallelism measuring probe 10 through the second interface 2212, the second interface 2212 is also used for receiving the light beam returned from the parallelism measuring probe 10, and the optical fiber circulator 221 is used for transmitting the received light beam to the spectrometer 230 through the third interface 2213.

In the present embodiment, the optical coupler 220 and the parallelism measuring probe 10 perform beam transmission through the optical fiber 30, and specifically, the first interface 2211 is connected to the wide-spectrum light source 210. The second interface 2212 is connected to the parallelism measuring probe 10 via the optical fiber 30. The third interface 2213 is connected to the spectrometer 230. The light beam output by the wide spectrum light source 210 is transmitted to the second interface 2212 through the first interface 2211, and is transmitted to the parallelism measuring probe through the optical fiber 30, and the divergent light beam is collimated into the parallel first light beam L1 through the collimating mirror 170, is transmitted to the first lens array 110 and the second lens array 120, and is emitted through the plurality of first lenses 111 and the plurality of second lenses 121, respectively. After the parallelism measuring probe 10 receives the returned light beam, the parallel fourth light beam L4 and the parallel seventh light beam L7 are converged into the eighth light beam L8 and the ninth light beam L9 through the collimator lens 170, respectively, and then transmitted to the second interface 2212. The eighth light beam L8 and the ninth light beam L9 are transmitted to the third interface 2213 through the second interface 2212 and to the spectrometer 230.

In the present embodiment, the spectral interferometer 20 is connected to the parallelism measuring probe 10 via the optical fiber 30. The length of the optical fiber 30 can be designed to be any length, so that the measuring length of the measuring device 1 is not limited, and the measuring device can be applied to long-distance measuring scenes.

Although embodiments of the present application have been shown and described, it should be understood that they have been presented by way of example only, and not limitation, and that various changes, modifications, substitutions and alterations can be made by those skilled in the art without departing from the scope of the present application, and such improvements and modifications are to be considered as within the scope of the present application.

Claims

1. A parallelism-measuring probe, characterized in that it comprises:

2. The parallelism-measuring probe of claim 1, wherein the first lens array comprises at least three first lenses, and the at least three first lenses are arranged in a non-collinear arrangement; the second lens array comprises at least three second lenses, and the at least three second lenses are arranged in a non-collinear arrangement.

3. The parallelism measuring probe of claim 2, wherein the beam-splitting face of the beam splitter is perpendicular to the plane of the mirror.

4. The parallelism measuring probe of claim 2, wherein the plane of the mirror is perpendicular to the plane of the first lens array, and the beam splitting surface of the beam splitter forms a 45 ° angle with the plane of the mirror.

5. The parallelism-measuring probe of claim 2, wherein the beam-splitting face of the beam splitter is parallel to the plane of the mirror.

6. The parallelism-measuring probe of any one of claims 1 to 5, further comprising:

7. The parallelism-measuring probe of claim 6, further comprising:

8. A measuring device, characterized in that the measuring device comprises:

a parallelism measuring probe according to any one of claims 1 to 7; and

9. The measurement arrangement according to claim 8, wherein the spectral interferometer comprises:

a wide spectrum light source for outputting a light beam;

the optical coupler is used for coupling the light beam output by the wide-spectrum light source to the parallelism measuring probe and coupling the light beam returned from the parallelism measuring probe to a spectrometer;

the spectrometer is used for receiving the light beams returning from the first object surface to be measured and the second object surface to be measured, and carrying out power spectrum measurement on the light beams returning from the parallelism measuring probe to obtain an interference power spectrum; and

10. The measurement device of claim 9, wherein when the parallelism measurement probe further comprises the fiber stub and the collimating mirror, the measurement device further comprises:

the optical coupler includes: