CN211180429U - Optical system for optical axis alignment - Google Patents

Abstract

The optical system for optical axis calibration of the present invention comprises a light source, a spectroscope, a first reflective mirror, a second reflective mirror and a detection component. The light source, the spectroscope and the first reflective mirror are sequentially arranged on a first straight line, The light source emits a beam toward the beam splitter, the second mirror is opposite to the first mirror, the detection component and the beam splitter are arranged on a second straight line, and the first straight line intersects the second straight line; the light source emits a beam, and the beam passes through the beam splitter A first beam is formed, and the beam is reflected by a beam splitter to form a second beam; the first beam is reflected by the first mirror and the second mirror in turn and enters the camera module; the second beam enters the detection component, and the first beam and the second beam There is a unique definite corresponding relationship; the optical system is adjusted so that the angle of the first beam meets the calibration requirements, and the optical axis of the camera module is set to coincide with the first beam to realize the optical axis calibration of the camera module.

Description

Optical system for optical axis alignment

technical field

The utility model belongs to the technical field of structural correction of a camera module, in particular to an optical system used for optical axis calibration.

Background technique

When the camera module is installed on the bracket, it is necessary to adjust the relative positional relationship between the camera module and the bracket, mainly the calibration of the optical axis of the camera module (active alignment, AA), so that when the bracket is installed on the mobile terminal, the camera The module can match the structure of the mobile terminal, so that the mobile terminal has better imaging quality.

The optical axis calibration of the existing camera module is mainly performed through the resolution test card of the camera module, and the calibration through the resolution test card often has the problem that it is difficult to determine the specifications. When the specification is too strict, it will increase the difficulty of calibration; when the given specification is too loose, it is easy to cause the positional deviation of the camera module, resulting in poor imaging. In addition, the camera module and the bracket often have a certain relative angle, and the prior art cannot calibrate the camera module with the relative angle.

Utility model content

The purpose of the present invention is to provide an optical system for optical axis calibration, which solves the above problems existing in the prior art.

In order to realize the purpose of the present utility model, the present utility model provides the following technical solutions:

In the first aspect, the embodiment of the present invention provides an optical system for optical axis calibration, which is used for calibrating the optical axis of a camera module, including a light source, a beam splitter, a first reflection mirror, a second reflection mirror and a detection component, The light source, the beam splitter and the first reflector are arranged in sequence on a first straight line, the light source emits light beams toward the beam splitter, and the second reflector is opposite to the first reflector , the detection component and the spectroscope are arranged on a second straight line, and the first straight line intersects the second straight line; the light source emits a light beam, and the light beam passes through the spectroscope to form a first The light beam is reflected by the beam splitter to form a second light beam; the first light beam is reflected by the first reflecting mirror and the second reflecting mirror in turn to enter the camera module; the second light beam Entering the detection component, the first beam and the second beam have a uniquely determined correspondence; the detection component detects the angle of the second beam relative to the optical axis of the detection component, The corresponding relationship between the two beams and the first beam, obtain the angle of the first beam relative to the optical axis of the camera module, adjust the optical system so that the angle of the first beam meets the calibration requirements, set the The optical axis of the camera module is coincident with the first light beam to realize the optical axis calibration of the camera module.

By arranging the structure of the light source, the beam splitter, the first reflection mirror, the second reflection mirror and the detection component, the detection component detects the angle of the second beam, and according to the corresponding relationship between the second beam and the first beam, the angle of the first beam is obtained , and then by adjusting the optical axis of the camera module to coincide with the first light beam, the optical axis calibration of the camera module can be realized. There is no problem that a given specification is difficult to determine, and an appropriate angle of the first light beam can be selected according to the relative angle of the camera module, and the camera module with the relative angle can be calibrated.

In an embodiment, the number of the light beams emitted by the light source is multiple, so that the number of the first light beam and the second light beam formed is multiple, and the multiple first light beams are in the The first reflecting mirror and the second reflecting mirror are reflected to form a preset angle to emit to the plurality of camera modules, and the plurality of the first light beams and the plurality of the second light beams have a one-to-one correspondence. The detection component detects the angles of the plurality of second beams relative to the optical axis of the detection component, and obtains a plurality of the The angle of the first beam relative to the optical axes of the plurality of camera modules, adjust the optical system so that the plurality of first beams meet the calibration requirements, and set the optical axes of the camera modules and the plurality of The first light beams are overlapped to achieve optical axis alignment of the plurality of camera modules.

The light source emits multiple beams, and the detection component detects the angle information of the second beam to obtain the angle information of the multiple first beams. By adjusting the optical system, the multiple first beams meet the optical axis calibration requirements, and then the multiple first beams meet the optical axis calibration requirements. The camera modules are respectively calibrated with each of the first light beams, so that the optical axis calibration of the plurality of camera modules can be completed. The problem of the optical axis consistency of the camera modules is solved, and the optical axis calibration requirements when multiple camera modules have relative angles can be met. The given specifications are determined, the calibration difficulty is low, and multiple camera modules can be calibrated at the same time.

In one embodiment, the plurality of first light beams are parallel or inclined to each other after being reflected by the first reflecting mirror and the second reflecting mirror. It can meet the optical axis calibration when the optical axes of multiple camera modules are parallel to each other or have relative angles.

In one embodiment, the angle between the first beam entering the camera module and the beam emitted by the light source is the first angle, and the second beam entering the detection component and the The included angle between the light beams emitted by the light source is the second included angle, and the corresponding relationship between the first included angle and the second included angle includes the angular correspondence between the first included angle and the second included angle. By taking the light beam emitted by the light source as a reference, the corresponding relationship between the first light beam and the second light beam is converted into the angle corresponding relationship between the first included angle and the second included angle, which is convenient for calculation and statistics.

In an embodiment, the optical system for optical axis calibration further includes a machine, when the detection component detects the second light beam, according to the corresponding relationship between the second light beam and the first light beam. When the obtained angle of the first light beam relative to the optical axis of the camera module meets the calibration requirements, the machine adjusts the position of the camera module so that the optical axis of the camera module and the camera module The first beams coincide. Set the machine to adjust the position of the camera module, provide a calibrated working surface, and support the camera module.

In an embodiment, the detection component includes a convex lens and an information collector arranged in sequence along the second straight line, the second light beam is focused on the information collector after passing through the convex lens, and the information collector is used for The angle information of the second light beam is collected. A convex lens is arranged to focus the divergent second light beams, so that the information collector can collect the angle information of the plurality of second light beams.

In one embodiment, an attenuation sheet for reducing the intensity of light is provided between the convex lens and the information collector. Setting attenuators is used to reduce the intensity of light, which can reduce the energy of light and protect the information collector.

In an embodiment, a light concentrator is arranged between the light source and the beam splitter, and the light concentrator is used to concentrate the light beam emitted by the light source to the outside. The light concentrator can concentrate the light beam and emit it, so that the light beam entering the beam splitter is at a preset angle to meet the needs of optical axis calibration.

In one embodiment, a progressive motor is connected to the light concentrator, and the progressive motor drives the light concentrator to move, so as to adjust the angle of the light beam emitted by the light concentrator. A progressive motor is set to adjust the position of the light concentrator, so that the angles of the light emitted by the light concentrator are different, so as to meet the calibration requirements when the relative angles of the optical axes of the multiple camera modules are different.

In one embodiment, the first reflector is an off-axis high-order hyperboloid reflector, and the second reflector is an off-axis paraboloid reflector. Through the combination of the off-axis high-order hyperboloid reflector and the off-axis paraboloid reflector, the propagation direction of the first light beam can be changed to meet the calibration requirements of the camera module.

In an embodiment, the light beam emitted by the light source is any two mixed light beams with different wavelengths of ultraviolet light, infrared light, visible light and laser light, and the beam splitter is used to divide the mixed light beam into two different wavelengths according to the range of wavelengths. The first light beam and the second light beam having different wavelengths. The light beams emitted by the light source are two kinds of mixed light beams. After passing through the beam splitter, two kinds of first light beams and second light beams with different wavelengths are formed, which are respectively emitted in different directions, without affecting the light intensity of each light beam, so that the first light beam detected by the information collector can be detected. The precision of the two light beams is higher, and the light intensity of the first light beam entering the camera module is sufficient at the same time, which facilitates the correspondence between the optical axis of the camera module and the first light beam.

In a second aspect, the present invention also provides an optical axis calibration method, the optical axis calibration method is performed using the optical system described in any one of the various embodiments of the first aspect, including: the light source emits a light beam, The light beam passes through the beam splitter to form a first beam, the beam is reflected by the beam splitter to form a second beam, and the first beam enters through the first reflector and the second reflector in sequence In the camera module, the second beam enters the detection component; wherein, the first beam and the second beam have a uniquely determined correspondence; the detection component detects that the second beam is relative to the Detecting the angle of the optical axis of the component, and obtaining the angle of the first beam relative to the optical axis of the camera module according to the corresponding relationship between the second beam and the first beam; adjusting the optical system so that all The angle of the first beam meets the calibration requirements; the optical axis of the camera module is set to coincide with the first beam to realize the optical axis calibration of the camera module. There is no problem that a given specification is difficult to determine, and an appropriate angle of the first light beam can be selected according to the relative angle of the camera module, and the camera module with the relative angle can be calibrated.

In an embodiment, the number of the light beams emitted by the light source is set to be multiple, so that the number of the first light beam and the second light beam to be formed is multiple, and the plurality of the first light beams are The first reflector and the second reflector are reflected to form a preset angle to emit to a plurality of the camera modules, and a plurality of the first light beams and the plurality of the second light beams have a one-to-one correspondence ; The detection component detects the angles of a plurality of the second light beams relative to the optical axis of the detection component, and obtains a plurality of the angle of the first light beam relative to the optical axes of the plurality of camera modules; adjust the optical system so that the plurality of the first light beams meet the calibration requirements; set the optical axes of the camera modules and a plurality of The first light beams are coincident to achieve optical axis alignment of the plurality of camera modules. The optical axis calibration of multiple camera modules can be realized.

In one embodiment, the angle between the first beam entering the camera module and the beam emitted by the light source is the first angle, and the second beam entering the detection component and the The included angle between the light beams emitted by the light source is the second included angle, and the corresponding relationship between the first included angle and the second included angle includes the angular correspondence between the first included angle and the second included angle. By taking the light beam emitted by the light source as a reference, the corresponding relationship between the first light beam and the second light beam is converted into the angle corresponding relationship between the first included angle and the second included angle, which is convenient for calculation and statistics.

In an embodiment, the optical system further includes a machine, when the detection component detects the second light beam and obtains the first light beam according to the corresponding relationship between the second light beam and the first light beam. When the angle of a light beam relative to the optical axis of the camera module meets the calibration requirements, the machine adjusts the position of the camera module so that the optical axis of the camera module coincides with the first light beam. Adjusting the position of the camera module through the machine can not only provide a working surface, but also facilitate adjustment and operation.

Description of drawings

In order to illustrate the embodiments of the present invention or the technical solutions in the prior art more clearly, the following briefly introduces the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description These are just some embodiments of the present invention, and for those of ordinary skill in the art, other drawings can also be obtained from these drawings without creative effort.

1 is a schematic structural diagram of an optical system for optical axis calibration according to an embodiment;

FIG. 2 is a schematic structural diagram of an optical system for optical axis calibration according to another embodiment.

Detailed ways

The technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the implementations. Way. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present invention.

Please refer to FIG. 1 , an embodiment of the present invention provides an optical system for optical axis calibration, including a light source 10 , a beam splitter 20 , a first reflection mirror 30 , a second reflection mirror 40 and a detection component (refer to FIG. 1 attached Figures 60, 70 and 80). The beam splitter 20 is disposed on the light-emitting side of the light source 10 , and the first reflecting mirror 30 is disposed on the side of the beam splitter 20 facing away from the light source 10 . In other words, the light source 10 , the beam splitter 20 and the first reflection mirror 30 are arranged on the first straight line X in sequence. The second mirror 40 is opposite to the first mirror 30 . The detection component is arranged on one side of the spectroscope 20, that is, the detection component and the spectroscope 20 are arranged on the second straight line Y, the first straight line X and the second straight line Y intersect, and the settings are different according to the type and angle of the spectroscope 20. , the included angles of the first straight line X and the second straight line Y may be different, and preferably, the first straight line X and the second straight line Y are perpendicular.

The light source 10 , the beam splitter 20 , the first reflector 30 , the second reflector 40 and the detection assembly can be installed on a support structure such as a support frame, a box, etc., for stable support. In order to avoid the influence of stray light on the results of calibration, the above structure should be set in a dark room.

The working process of the above structure: the light source 10 emits a light beam 100 , the light beam 100 passes through the beam splitter 20 to form a first beam 101 , and the beam 100 is reflected by the beam splitter 20 to form a second beam 102 . The first light beam 101 is sequentially reflected by the first reflecting mirror 30 and the second reflecting mirror 40 and then enters the camera module 51 . The second beam 102 enters the detection assembly. The first light beam 101 and the second light beam 102 have a uniquely determined correspondence. The detection component detects the angle of the second beam 102 relative to the optical axis of the detection component, and obtains the angle of the first beam 101 relative to the optical axis of the camera module according to the corresponding relationship between the second beam 102 and the first beam 101, and adjusts the optical system so that The angle of the first light beam satisfies the calibration requirement, and the optical axis of the camera module 51 is set to coincide with the first light beam 101 to realize the optical axis calibration of the camera module 51 .

The principle of the above working process is as follows: the optical axis of the camera module 51 coincides with the first light beam 101 entering the camera module 51, and the optical axis of the camera module 51 is calibrated. After the light source 10 emits the light beam 100 and splits the light beam 100 by the beam splitter 20 , the first beam 101 and the second beam 102 have a corresponding relationship, and the corresponding relationship is related to the shape of the beam splitter 20 . The first light beam 101 is reflected by the first reflector 30 and the second reflector 40 and then exits in a preset direction. When the shapes of the beam splitter 20, the first reflector 30 and the second reflector 40 are determined, they enter the camera module There is a corresponding relationship between the first light beam 101 of 51 and the second light beam 102 entering the detection component. By detecting the angle information of one of the first light beam 101 or the second light beam 102, the angle information of the other can be obtained through the corresponding relationship between the two.

In one embodiment, the angle between the first beam 101 entering the camera module 51 and the beam 100 emitted by the light source 10 that has not yet entered the beam splitter 20 is the first angle, and the second beam 102 entering the detection component is The included angle between the light beams 100 emitted by the light source 100 that have not yet entered the beam splitter 20 is the second included angle, and the corresponding relationship between the first light beam 101 and the second light beam 102 includes the angular correspondence between the first included angle and the second included angle . Using the light beam 100 emitted by the light source 10 as a reference, the corresponding relationship between the first light beam 101 and the second light beam 102 is converted into the angle corresponding relationship between the first included angle and the second included angle, which is convenient for calculation and statistics.

In an embodiment, the light incident surface and the light exit surface of the beam splitter 20 are parallel planes, so the light beam 100 emitted by the light source 10 and the first beam 101 just emitted from the light exit surface of the beam splitter 20 are parallel to each other, that is, The first included angle between the first light beam 101 and the light beam 100 emitted from the light-emitting surface of the beam splitter 20 is 0°. The first included angle between the first light beam 101 entering the camera module 51 and the light beam 100 is only related to the angle of the light beam 100 initially incident on the light incident surface of the beam splitter 20 . The first angle can be obtained by detecting the angle of the second light beam 102 by the detection component to obtain the second angle. When adjusting the angle of the first light beam 101 entering the camera module 51 , it is sufficient to adjust the angle of the light source 10 , that is, the angle of the light beam 100 emitted by the light source 10 . By detecting the angle of the second light beam 102 by the detection component, it can be determined whether the angle of the first light beam 101 entering the camera module 51 is in place.

In other embodiments, the light incident surface and the light output surface of the beam splitter 20 may be non-parallel planes, and the method for adjusting the first light beam 101 entering the camera module 51 may include adjusting the light source 10, the beam splitter 20, the first reflection The angle of any one or more of the mirror 30 and the second mirror 40 is realized.

The correspondence between the first light beam 101 entering the camera module 51 and the second light beam 102 entering the detection component can be determined by calibration. For example, by emitting light beams 100 with different angles multiple times, collecting the angle information of the first light beam 101 and the second light beam 102, storing the angle information of the above three light beams, and establishing a data statistical database, the emission angle of the light beam 100 , The angle of the first beam 101 and the angle of the second beam 102 are in a one-to-one correspondence. When the optical axis of the camera module 51 is calibrated later, according to the angle requirements of the first beam 101, the light source can be determined through the data statistics database. The emission angle of the beam 100 of 10.

When the camera module 51 is installed on the bracket, there will be angle requirements according to design requirements. The light beam 100 is emitted by the light source 10, and the detection component detects the angle of the second beam 102, and the angle of the first beam 101 can be obtained. When the angle of the first beam 101 is consistent with the angle required by the design of the camera module 51, the camera can be captured. The optical axis of the module 51 is calibrated. During calibration, the position of the camera module 51 and the first beam 101 are matched, and the movement and rotation of the camera module 51 are adjusted so that the optical axis of the camera module 51 coincides with the first beam 101, and the optical axis of the camera module 51 is completed. axis calibration.

Specifically, the optical system used for optical axis calibration also includes a machine (not shown in the figure). When the angle of the optical axis meets the calibration requirements, the machine adjusts the position of the camera module 51. For example, the machine is provided with a mechanical structure such as a mechanical arm, and the camera module 51 is adjusted to move and rotate, so as to make the camera module 51 move and rotate. The optical axis coincides with the first light beam 101 . A machine is set to adjust the position of the camera module 51 to provide a calibrated working surface to support the camera module 51 . Further, the bracket connected to the camera module 51 is fixed on the machine, and after the machine adjusts the position of the camera module 51 to achieve optical axis calibration, the machine can also connect and fix the camera module 51 to the bracket, for example, by dispensing glue. , welding, etc. to achieve the fixing of the camera module 51 and the bracket.

The specific calibration method can be as follows: the image of the first beam 101 captured by the photosensitive element of the camera module 51 is compared with the optical axis of the lens of the camera module 51, and the image formed by the first beam 101 on the photosensitive element is located in the photosensitive element. and the light intensity in the image is evenly distributed around the geometric center point of the photosensitive element, then the first light beam 101 coincides with the optical axis of the camera module 51 .

The calibrated camera module 51 is fixed to the bracket, and the bracket and the camera module 51 are installed together on a mobile terminal, such as a smart phone, a tablet computer, etc., which can ensure the imaging quality of the mobile terminal.

Therefore, by setting the structure of the light source 10, the beam splitter 20, the first reflecting mirror 30, the second reflecting mirror 40 and the detection component, the detection component detects the angle of the second light beam 102, according to the correspondence between the second light beam 102 and the first light beam 101 Then, by adjusting the optical axis of the camera module 51 to coincide with the first light beam 101, the optical axis of the camera module 51 can be calibrated. There is no problem that a given specification is difficult to determine, and an appropriate angle of the first light beam 101 can be selected according to the relative angle of the camera module 51 , and the camera module 51 with the relative angle can be calibrated.

Wherein, the light source 10 can be any type with a relatively simple structure that emits ultraviolet light, infrared light, visible light or laser light, and the light source 10 can also be any type that emits ultraviolet light, infrared light, visible light or laser light with a slightly complicated structure. two types. In other words, the light beam 100 emitted by the light source 10 is wavelength-dependent and can be an independent beam of any one of ultraviolet light, infrared light, visible light and laser light, or a mixture of any two of ultraviolet light, infrared light, visible light and laser light. beam.

When the light beam 100 emitted by the light source 10 is an independent light beam of any one of ultraviolet light, infrared light, visible light and laser light, the light beam 100 does not change the wavelength of the light when it is split by the beam splitter 20, that is, the first light beam 101 and the second light beam 102 are the same light. Preferably, the camera module 51 is a conventional color visible light camera, then the light beam 100 emitted by the light source 10 is visible light, and the first light beam 101 and the second light beam 102 after the light beam 100 is split by the beam splitter 20 are both visible light, so that they enter the camera. The first light beam 100 of the module 51 is visible light, and the photosensitive element of the camera module 51 can capture the first light beam 101 , which facilitates the calibration of the optical axis of the camera module 51 . In other possibilities, the camera module 51 can also be an infrared light camera, an ultraviolet light camera, a laser camera, etc. Correspondingly, the light beam 10 emitted by the light source 10 is infrared light, ultraviolet light, laser light, and the like. The light beam 100 emitted by the light source 10 is a single independent light beam, and the selection of the information collector 80 is easy.

When the light beam 100 emitted by the light source 10 is any two mixed light beams with different wavelengths of ultraviolet light, infrared light, visible light and laser light, the beam splitter 20 is used for dividing the mixed light beam into first light beams 101 with different wavelengths according to the range of wavelengths and the second beam 102 . For example, if the camera module 51 is a colored visible light camera, and the detection component can detect infrared light, the light beam 100 is a mixed light of infrared light and visible light, and the beam splitter 20 divides the light beam 100 into a first light beam 101 of visible light and a second light beam of infrared light 102. Alternatively, the camera module 51 is an infrared camera, the detection component can detect ultraviolet light, the light beam is a mixed light of infrared light and ultraviolet light, and the beam splitter 20 divides the light beam 100 into a first beam 101 of infrared light and a second beam of ultraviolet light. beam 102. Other mixed beams are no longer enumerated, just refer to them. The light beams emitted by the light source 10 are two kinds of mixed light beams. After passing through the beam splitter 20, two kinds of first light beams 101 and second light beams 102 with different wavelengths are formed respectively to be emitted in different directions, without affecting the light intensity of each light beam, so that information collection is possible. The accuracy of the second light beam 102 detected by the detector 80 is higher, and the light intensity of the first light beam 101 entering the camera module 51 is sufficient to facilitate the correspondence between the optical axis of the camera module 51 and the first light beam 101 .

The beam splitter 20 can be a prism, and further can be a polarizing prism, which can transmit light of some wavelengths, and reflect the light of other wavelengths without being transmitted. The surface of the beam splitter 20 can be coated to change the wavelength range of the light that can be transmitted. The beam splitter 20 and the beam 100 should have an inclination angle, that is, the surface on which the beam 100 enters the beam splitter 20 is not perpendicular to the beam 100 .

The first reflector 30 is an off-axis high-order hyperboloid reflector, and the second reflector 40 is an off-axis paraboloid reflector. The off-axis high-order hyperboloid mirror has different positions on the reflective surface, and the angle of light reflection is different, wherein the high-order refers to the aspheric high-order term. Off-axis parabolic mirrors also have similar properties. Through the combination of the off-axis high-order hyperboloid mirror and the off-axis parabolic mirror, the propagation direction of the first light beam 101 can be changed to meet the calibration requirements of the camera module 51 .

In this embodiment, as shown in FIG. 1 , when the light beam 100 is emitted in the horizontal direction (ie, the extending direction of the first straight line X), the beam splitter 20 does not change the propagation direction of the transmitted first light beam 101 , and passes through the first reflecting mirror 30 After being reflected by the off-axis high-order hyperboloid mirror, the propagation direction of the first beam 101 is changed to be inclined to the upper left. After being reflected by the off-axis parabolic mirror of the second mirror 40, the propagation direction of the first beam 101 is changed to Vertically downward, it is convenient to be aligned with the camera module 51 which is arranged on the horizontal plane and whose optical axis direction is the vertical direction. In addition, it can be seen from the propagation path of the light beams in FIG. 1 that when there are multiple light beams 100 and propagate in a divergent shape, the off-axis high-order hyperbolic mirror of the first mirror 30 and the off-axis paraboloid of the second mirror 40 reflect The combination of mirrors can regularize the plurality of divergent first light beams 101 into substantially parallel directions, and emit toward the plurality of camera modules 51 , 52 , and 53 . The calibration of multiple camera modules will be described later.

With the advancement of technology, existing mobile terminals often use multiple cameras to implement different functions respectively. For example, multiple cameras respectively implement wide-angle, telephoto, macro shooting, etc., or, multiple cameras respectively implement visible light shooting, infrared light shooting, and the like. A plurality of camera modules are generally installed on the same bracket to form an assembly, and then the assembly is assembled to the mobile terminal as a whole.

For the optical axis calibration of multiple camera modules, the existing calibration technology is generally calibrated based on the bracket. If the multi-camera module consists of modules A, B, and C, first calibrate the relative position of module A and the bracket, that is, calibrate module A according to the chart, and adjust the two vertical directions of the module along the plane (that is, along the x-axis direction and along the y-axis direction) and the offset to the direction perpendicular to the in-plane direction (ie, the rotation in the z-axis direction) until the desired specification is achieved. Similarly, adjust the relative positions of module B and module C and the bracket to complete the optical axis calibration of multiple camera modules.

The existing optical axis calibration technology of multiple camera modules has the following disadvantages:

1. The core content of optical axis calibration of multiple camera modules is to ensure the optical axis consistency of each single module. However, it is difficult to ensure the consistency of the optical axis with the position calibration of a single module.

2. The single module must have a certain relative angle to make the imaging quality of the multi-module the best, and the original technology obviously cannot adjust the relative angle position of each single module.

3. It is difficult to determine the given specifications. When the specifications are too strict, it will increase the difficulty of calibration; when the given specifications are too loose, it is easy to cause the position deviation of each module, which will eventually lead to poor imaging.

4. Only one camera module can be calibrated at a time, and simultaneous calibration of multiple camera modules cannot be achieved.

In order to solve the problem of optical axis calibration of multiple camera modules, in an embodiment, referring to FIG. 1, the number of light beams 100 emitted by the light source 10 is multiple, so that the formed first light beam 101 and the second light beam 102 are equal to each other. The number is multiple. The plurality of first light beams 101 are reflected at the first reflecting mirror 30 and the second reflecting mirror 40 to form a preset angle and are emitted to the plurality of camera modules 51 , 52 and 53 . The plurality of first light beams 101 and the plurality of second light beams 102 have a one-to-one correspondence. The detection component detects the angles of the plurality of second light beams 102 relative to the optical axis of the detection component, and according to the plurality of second light beams 102 and the plurality of first light beams 102 The one-to-one correspondence between the angles of the light beams 101 is used to obtain the angles of the plurality of first light beams 101 relative to the optical axes of the plurality of camera modules 51, 52, and 53, and the optical system is adjusted to make the plurality of first light beams 101 meet the calibration requirements. The optical axes of the camera modules 51 , 52 , and 53 are coincident with the plurality of first light beams 51 , 52 , and 53 to achieve optical axis alignment of the plurality of camera modules 51 , 52 , and 53 .

Similar to the working principle of the optical axis calibration of the single camera module 51 described above, after the multiple beams 100 are split by the beam splitter 20, the multiple first beams 101 are used for calibrating with the multiple camera modules 51, 52, 53, and detecting The angles of the plurality of second light beams 102 are used to determine whether the plurality of first light beams 101 meet the preset angle requirements. Since the plurality of second light beams 101 are in one-to-one correspondence with the plurality of first light beams 101, and each first light beam 101 is used to correspond to one camera module, the light source 10 emits the plurality of light beams 100, and the detection component detects the second light beam 100. By adjusting the optical system, for example, adjusting the angle of the light beam 100 emitted by the light source 10, the inclination of the beam splitter 20, the first reflector 30 and the second The relative positional relationship of the reflector 40 can make multiple first beams 101 meet the optical axis calibration requirements, and then the multiple camera modules 51, 52, 53 are respectively calibrated with each corresponding first beam 101, and then you can Completing the optical axis calibration of the multiple camera modules 51 , 52 and 53 . A plurality of camera modules 51 , 52 , and 53 that have been calibrated are fixed on the same bracket, and after the formed whole is installed on the mobile terminal, the imaging quality can be guaranteed.

Compared with the existing calibration technology of multiple camera modules, the optical axis calibration technology of this embodiment overcomes the disadvantages of the existing technology. Because each first beam 101 corresponds to each camera module one-to-one, the problem of the consistency of the optical axes of the camera modules is solved; and the angle of each first beam 101 can be set as required, and multiple first beams 101 can be set. A difference in the angles between the light beams 101 can satisfy the optical axis calibration requirement when the multiple camera modules have relative angles; since the angles of the multiple first light beams 101 can be uniquely determined by the detection components, and the The optical axes of the modules 51, 52, and 53 only need to be calibrated with the multiple first beams 101. The given specifications are determined, and the calibration difficulty is low; obviously, this embodiment can calibrate multiple camera modules at the same time, which improves the multiple camera modules. Efficiency of optical axis alignment of modules 51, 52, 53.

It should be understood that, generally, the number of the plurality of camera modules is 2, 3 or 4, then the number of the light beams 100 emitted by the light source 10 is corresponding to 2, 3 or 4. For example, FIG. 1 shows that the light beams 100 are Three camera modules 51, 52 and 53 can be used for optical axis calibration. The optical axis calibration of other number of multiple camera modules can be referred to in the same way, and the number of multiple camera modules is not limited to 2, 3 or 4, but can be more.

In an embodiment, referring to FIG. 1 , the plurality of first light beams 101 are reflected by the first reflecting mirror 30 and the second reflecting mirror 40 and are parallel to each other, which can satisfy the optical axes of the plurality of camera modules 51 , 52 and 53 . Alignment of optical axes when they are parallel to each other. The first reflector 30 is an off-axis high-order hyperboloid reflector, and the second reflector 40 is an off-axis paraboloid reflector. The above requirements can be achieved by reasonably setting the surface shapes of the reflecting surfaces of the off-axis high-order hyperboloid reflector and the off-axis parabolic reflector.

In other embodiments, the plurality of first light beams 101 are not parallel to each other but are inclined to each other after being reflected by the first reflecting mirror 30 and the second reflecting mirror 40, which can satisfy the requirement that the optical axes of the plurality of camera modules 51, 52, and 53 have relative angles. when the optical axis is calibrated.

In an embodiment, please refer to FIG. 1 , the detection assembly includes a convex lens 60 and an information collector 80 arranged in sequence along the second straight line Y. The second light beam 102 is focused on the information collector 80 after passing through the convex lens 60 , and the information collector 80 is used for collecting the angle information of the second light beam 102 . Since the beam splitter 20 reflects the plurality of light beams 100 to form a plurality of second light beams 102 , following the principle of light reflection, the relative angles between the plurality of light beams 100 are not changed, and the reflected second light beams 102 are still divergent and difficult to be detected by the information collector. Therefore, the convex lens 60 is provided to focus the divergent second light beams 102 , so that the information collector 80 can collect the angle information of the plurality of second light beams 102 .

After the shape of the convex lens 60 is determined, there is still a one-to-one correspondence between the second light beam 102 after passing through the convex lens 60 and the first light beam 101 entering the camera module. With the angle information, the angle of the first light beam 101 can be determined according to the corresponding relationship.

The information collector 80 is, for example, a camera and an information processing device such as a computer connected to the camera. The camera captures an image of the second beam 102, and the computer and other information processing devices analyze the image captured by the camera, so that the relative relationship between the second beam 102 and the camera can be obtained. Angle information of the optical axis.

In one embodiment, with continued reference to FIG. 1 , an attenuation sheet 70 for reducing the intensity of light is provided between the convex lens 60 and the information collector 80 . For example, when the second light beam 102 is infrared light, ultraviolet light, or laser light, the energy of the light is very high, which is easy to damage the information collector 80. Therefore, the attenuation sheet 70 is provided to reduce the light intensity, which can reduce the light energy and protect the information. Collector 80. The surface of the attenuation sheet 70 can also be coated, and the intensity of the light transmitted through the attenuation sheet 70 can be adjusted as required, so that the light intensity entering the information processor 80 is appropriate, neither too large nor too small.

In an embodiment, please refer to FIG. 2 , a light concentrator 92 is arranged between the light source 10 and the beam splitter 20 , and the light concentrator 92 is used for concentrating the light beam emitted by the light source 10 to exit. The light concentrator 92 can concentrate the light beams to exit, so that the light beams 100 entering the beam splitter 20 are at a preset angle, which meets the requirement of optical axis alignment.

In one embodiment, referring to FIG. 2 , the light concentrator 92 is connected with a progressive motor 91 , and the progressive motor 91 drives the light concentrator 92 to move so as to adjust the angle of the light beam emitted by the light concentrator 92 . For a plurality of camera modules 51 , 52 , and 53 with different relative angles of optical axes, the incident angle of the first beam 101 needs to be adjusted during optical axis calibration. After the structure is fixed, one of the means to adjust the angle of the first light beam 101 is to adjust the incident angle of the light source 10. Therefore, the progressive motor 91 is set to adjust the position of the light concentrator 92, so that the angles of the light emitted by the light concentrator 92 are different, thereby It satisfies the calibration requirement when the relative angles of the optical axes of the plurality of camera modules 51 , 52 and 53 are different.

The light concentrator 92 and the progressive motor 91 can be integrated with the light source 10 in a one-piece structure.

What is disclosed above is only a preferred embodiment of the present invention, of course, it cannot limit the scope of rights of the present invention. Those of ordinary skill in the art can understand that all or part of the process for realizing the above-mentioned embodiment can be implemented according to the present invention. The equivalent changes made by the claims of the utility model still belong to the scope covered by the utility model.

Claims (11)

1. An optical system for calibrating an optical axis of a camera module is used for calibrating the optical axis of the camera module and is characterized by comprising a light source, a spectroscope, a first reflecting mirror, a second reflecting mirror and a detection assembly, wherein the light source, the spectroscope and the first reflecting mirror are sequentially arranged on a first straight line, the light source emits a light beam towards the spectroscope, the second reflecting mirror is opposite to the first reflecting mirror, the detection assembly and the spectroscope are arranged on a second straight line, and the first straight line is intersected with the second straight line;

the light source emits a light beam, the light beam penetrates through the spectroscope to form a first light beam, and the light beam is reflected by the spectroscope to form a second light beam; the first light beam is reflected by the first reflecting mirror and the second reflecting mirror in sequence and enters the camera module; the second light beam enters the detection assembly, and the first light beam and the second light beam have a unique determined corresponding relation; the detection assembly detects the angle of the second light beam relative to the optical axis of the detection assembly, the angle of the first light beam relative to the optical axis of the camera module is obtained according to the corresponding relation between the second light beam and the first light beam, the optical system is adjusted to enable the angle of the first light beam to meet the calibration requirement, and the optical axis of the camera module is arranged to coincide with the first light beam to achieve the optical axis calibration of the camera module.

2. The optical system for optical axis calibration according to claim 1, wherein the number of the light beams emitted by the light source is plural, so that the number of the first light beams and the second light beams formed is plural, the plural first light beams are reflected at the first reflecting mirror and the second reflecting mirror to form a predetermined angle and are emitted to the plural camera modules, the plural first light beams and the plural second light beams have a one-to-one correspondence relationship, the detecting component detects the angle of the plural second light beams with respect to the optical axis of the detecting component, obtains the angle of the plural first light beams with respect to the optical axes of the plural camera modules according to the one-to-one correspondence relationship between the plural second light beams and the plural first light beams, adjusts the optical system so that the plural first light beams satisfy the calibration requirement, and sets the optical axes of the plural camera modules to coincide with the plural first light beams to realize the plural camera modules The optical axes of the groups are aligned.

3. The optical system for optical axis calibration as claimed in claim 2, wherein a plurality of the first light beams are parallel to each other or inclined to each other after being reflected by the first reflecting mirror and the second reflecting mirror.

4. The optical system for optical axis calibration according to claim 1, wherein an angle between the first light beam entering the camera module and the light beam emitted from the light source is a first angle, an angle between the second light beam entering the detection assembly and the light beam emitted from the light source is a second angle, and a correspondence between the first light beam and the second light beam includes an angle correspondence between the first angle and the second angle.

5. The optical system according to any one of claims 1 to 4, further comprising a stage, wherein when the detecting element detects the second light beam and the angle of the first light beam relative to the optical axis of the camera module, which is obtained according to the corresponding relationship between the second light beam and the first light beam, meets the calibration requirement, the stage adjusts the position of the camera module so that the optical axis of the camera module coincides with the first light beam.

6. The optical system for optical axis calibration according to any one of claims 2 or 3, wherein the detection component includes a convex lens and an information collector, which are sequentially disposed along the second straight line, the second light beam passes through the convex lens and then focuses on the information collector, and the information collector is configured to collect angle information of the second light beam.

7. The optical system for optical axis calibration of claim 6, wherein an attenuation sheet for attenuating the intensity of light is disposed between the convex lens and the information collector.

8. An optical system for optical axis calibration as claimed in any one of claims 1 to 4, wherein a light concentrator is provided between the light source and the beam splitter, the light concentrator being configured to concentrate the light beam emitted by the light source to exit outwards.

9. The optical system for optical axis calibration of claim 8 wherein said light concentrator is coupled with a stepper motor, said stepper motor driving said light concentrator to move to adjust the angle of the light beam exiting said light concentrator.

10. The optical system for optical axis calibration of any of claims 1 to 4 wherein the first mirror is an off-axis higher order hyperboloid mirror and the second mirror is an off-axis parabolic mirror.

11. The optical system for optical axis calibration as claimed in any one of claims 1 to 4, wherein the light beam emitted from the light source is a mixed light beam of any two of ultraviolet light, infrared light and visible light with different wavelengths, and the beam splitter is configured to split the mixed light beam into the first light beam and the second light beam with different wavelengths according to a range of wavelengths.

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