An automatic measurement device and method for optical fiber mode field diameter

Abstract

The present invention provides an automated measurement device and method for optical fiber mode field diameter, comprising: a first slide, a beam quality analyzer, and a base, wherein: the first slide and the beam quality analyzer are sequentially arranged on the base; the first slide is used to set an optical fiber to be measured, and drive the optical fiber to be measured to move or rotate in different directions, so as to adjust the axial distance between the end face of the optical fiber to be measured and the beam quality analyzer, and adjust the position and ellipticity of a light spot emitted by the optical fiber to be measured on the beam quality analyzer, so as to accurately measure the light spot emitted by the optical fiber to be measured at different axial distance positions through the beam quality analyzer, obtain the light spot radius corresponding to the optical fiber to be measured at different axial distance positions, obtain the mode field diameter of the optical fiber to be measured according to the light spot radius corresponding to the optical fiber to be measured at different axial distance positions and the corresponding axial distance, and improve the measurement accuracy of the mode field diameter of the optical fiber to be measured by adjusting the light spot ellipticity by the first slide.

Description

Technical Field

[0001] The present invention relates to the technical field of signal processing, and in particular to an automatic measurement device and method for optical fiber mode field diameter. Background Art

[0002] During the transmission of light in an optical fiber, it is impossible for the light beam to be completely concentrated in the fiber core for transmission. Some energy will also be transmitted in the cladding of the optical fiber. At this time, the diameter of the optical fiber core cannot fully reflect the energy distribution of the light in the optical fiber.

[0003] In existing technology, the mode field diameter is commonly used to characterize the distribution of fundamental mode light within the core region of a single-mode optical fiber. The fundamental mode light intensity is highest at the core axis and gradually decreases with increasing distance from the axis. Therefore, accurately measuring the mode field diameter of an optical fiber can help to gain a deeper understanding of its characteristics, provide accurate parameters for optical fiber production, and improve production quality.

[0004] In the existing methods for measuring the mode field diameter of optical fibers, a fiber-coupled three-dimensional displacement stage is often used to adjust the relative position of the measuring instrument and the optical fiber so that the measuring instrument is aligned with the axis of the optical fiber's light-emitting end. The measuring instrument usually uses a charge coupled device (CCD). A CCD (Charging Device) camera is used to capture an image of the light-emitting end of the optical fiber. The existing measurement method has the following problems: to calculate the mode field diameter of the optical fiber, it is necessary to pre-measure the radius of the light spot emitted by the optical fiber on the measuring instrument, and then calculate the mode field diameter based on the radius of the light spot. The radius of the light spot can only be accurately obtained if the ellipticity of the light spot meets the requirements (i.e., the shape of the light spot must be as close to a circle as possible). When the ellipticity of the light spot does not meet the requirements, the measured spot radius is inaccurate, which in turn leads to an inaccurate mode field diameter obtained by subsequent calculation. The three-dimensional translation stage used in the prior art cannot adjust the ellipticity of the light spot, so the measurement accuracy is usually relatively low. It is only suitable for measuring the mode field diameter of engineering optical fibers and is not applicable to situations where higher measurement accuracy is required. On the other hand, due to the pixel limitations of the CCD camera used in the prior art, it is difficult to capture a relatively clear image of the light-emitting end, which also leads to errors in the measurement of the light spot radius, which also affects the accuracy of the mode field diameter measurement.

[0005] In view of this, overcoming the defects of the prior art is an urgent problem to be solved in this technical field. Summary of the Invention

[0006] The technical problem to be solved by the present invention is how to improve the accuracy of measuring the mode field diameter of an optical fiber.

[0007] The present invention adopts the following technical solutions:

[0008] In a first aspect, an automated optical fiber mode field diameter measurement device is provided, comprising: a first slide 1, a beam quality analyzer 2, and a base 3, wherein:

[0009] The first slide 1 and the beam quality analyzer 2 are sequentially arranged on the base 3;

[0010] The first slide 1 is used to set the optical fiber 4 to be tested, and drive the optical fiber 4 to be tested to move horizontally, vertically, and rotate vertically and horizontally to adjust the axial distance between the end face of the optical fiber 4 to be tested and the beam quality analyzer 2, as well as to adjust the position and ellipticity of the light spot emitted by the optical fiber 4 to be tested on the beam quality analyzer 2;

[0011] The beam quality analyzer 2 is used to measure the light spot emitted by the optical fiber 4 to be tested at different axial distance positions to obtain the light spot radius corresponding to the optical fiber 4 to be tested at different axial distance positions, and obtain the mode field diameter of the optical fiber 4 to be tested based on the light spot radius corresponding to the optical fiber 4 to be tested at different axial distance positions and the corresponding axial distance.

[0012] Preferably, the first slide 1 specifically includes: a first base 11, a first horizontal moving assembly 12, a first vertical moving member 13, a first vertical axial rotating member 14, a first horizontal axial rotating member 15 and a clamp 16, wherein:

[0013] The first base 11 is located at the bottom end of the first slide 1, and the first horizontal moving assembly 12 is provided at the upper end of the first base 11. The first horizontal moving assembly 12 is used for moving in the X-axis and Y-axis directions. A vertical guide rail is provided on the side of the first horizontal moving assembly 12;

[0014] The first vertical moving member 13 is disposed on a side surface of the first horizontal moving assembly 12 and is slidably connected to the vertical guide rail;

[0015] The first vertical moving member 13 is provided with a first arc surface, and the first arc surface is provided with a vertical axial arc guide rail;

[0016] The first vertical axial rotating member 14 is provided on the first arc surface and is slidably connected to the vertical axial arc guide rail. The upper end of the first vertical axial rotating member 14 is provided with a second arc surface, and the second arc surface is provided with a horizontal axial arc guide rail;

[0017] The first horizontal axial rotating member 15 is provided on the second arc surface and is slidably connected to the horizontal axial arc guide rail;

[0018] The clamp 16 is disposed on the first horizontal axial rotating member 15 , and the clamp 16 is used to fix the optical fiber 4 to be tested.

[0019] Preferably, the first horizontal moving assembly 12 includes a first X-axis slide 121 and a first Y-axis slide 122, wherein:

[0020] An X-axis slide rail is provided on the first base 11, and the first X-axis slide table 121 is provided on the first base 11 and is slidably connected to the X-axis slide rail;

[0021] The first X-axis slide 121 is provided with a Y-axis slide rail, and the first Y-axis slide 122 is provided on the first X-axis slide 121 and is slidably connected to the first Y-axis slide 122;

[0022] The vertical guide rail is provided on the side of the first Y-axis slide 122 , and the first vertical moving member 13 is provided on the side of the first horizontal moving component 12 and is slidably connected to the vertical guide rail.

[0023] Preferably, the optical fiber mode field diameter automatic measuring device further includes a second slide 5, wherein:

[0024] The second slide 5 is arranged on the base 3, and the beam quality analyzer 2 is arranged on the second slide 5;

[0025] The second slide 5 is used to drive the beam quality analyzer 2 to move horizontally and rotate horizontally axially to adjust the initial relative position between the beam quality analyzer 2 and the optical fiber 4 to be tested.

[0026] Preferably, the second slide 5 specifically includes: a second base 51, a second horizontal moving assembly 52, and a second horizontal axial rotating member 53, wherein:

[0027] The second base 51 is provided on the base 3, and the second horizontal moving assembly 52 is provided on the upper end of the second base 51. The second horizontal moving assembly 52 is used for moving in the X-axis direction and the Y-axis direction. The second horizontal moving assembly 52 is provided with a third arc surface, and the third arc surface is provided with a horizontal axial arc guide rail;

[0028] The second horizontal axial rotating member 53 is provided on the third arc surface and is slidably connected to the horizontal axial arc guide rail;

[0029] The beam quality analyzer 2 is disposed on the second horizontal axial rotating member 53 .

[0030] Preferably, the second horizontal moving assembly 52 includes a second X-axis slide 521 and a second Y-axis slide 522, wherein:

[0031] The second base 51 is provided with a Y-axis slide rail, and the second Y-axis slide 522 is provided on the second base 51 and is slidably connected to the Y-axis slide rail;

[0032] The second Y-axis slide 522 is provided with an X-axis slide rail, and the second X-axis slide 521 is provided on the second Y-axis slide 522 and is slidably connected to the second X-axis slide 521;

[0033] The second X-axis slide 521 is provided with the third arc surface, and the third arc surface is provided with a horizontal axial arc guide rail. The second horizontal axial rotating member 53 is provided on the third arc surface and is slidably connected to the horizontal axial arc guide rail.

[0034] In a second aspect, a method for automatically measuring the mode field diameter of an optical fiber is provided, which is used in the aforementioned automatic measurement device for the mode field diameter of an optical fiber, and comprises:

[0035] The optical fiber 4 to be tested is placed on the first slide 1, and the optical fiber 4 to be tested is connected to the light source;

[0036] The first slide 1 is adjusted to adjust the relative position between the optical fiber 4 to be tested and the beam quality analyzer 2, and the beam quality analyzer 2 is used to measure the light spots emitted by the optical fiber 4 to be tested at different axial distances to obtain the light spot radii corresponding to the optical fiber 4 to be tested at different axial distances;

[0037] The mode field diameter of the optical fiber 4 to be tested is obtained according to the spot radius corresponding to the optical fiber 4 to be tested at different axial distance positions and the corresponding axial distance.

[0038] Preferably, the step of adjusting the relative position between the optical fiber 4 to be tested and the beam quality analyzer 2 by adjusting the first slide 1, and measuring the light spots emitted by the optical fiber 4 to be tested at different axial distance positions by the beam quality analyzer 2 to obtain the light spot radii corresponding to the optical fiber 4 to be tested at different axial distance positions, specifically includes:

[0039] By adjusting the axial position of the first slide 1 or the axial position of the beam quality analyzer 2, the end face of the optical fiber 4 to be tested and the beam quality analyzer 2 are at a first preset axial distance;

[0040] Adjust the first slide 1 and obtain the spot radius corresponding to the optical fiber to be tested 4 at the first preset axial distance through the beam quality analyzer 2;

[0041] By adjusting the axial position of the first slide 1 or the axial position of the beam quality analyzer 2, the end face of the optical fiber 4 to be tested and the beam quality analyzer 2 are at a second preset axial distance;

[0042] The first slide 1 is adjusted and the beam quality analyzer 2 is used to obtain the spot radius corresponding to the optical fiber to be tested 4 at the first preset axial distance.

[0043] Preferably, adjusting the first slide 1 and obtaining the spot radius corresponding to the optical fiber to be tested 4 at the first preset axial distance through the beam quality analyzer 2 specifically includes:

[0044] Traversing the moving positions of the first slide 1, and obtaining the ellipticity of the light spot corresponding to the optical fiber to be tested 4 at a first preset axial distance through the beam quality analyzer 2;

[0045] Determining in real time whether the ellipticity of the light spot is greater than a preset threshold;

[0046] When the ellipticity of the light spot is less than or equal to the preset threshold, the moving position of the first slide 1 continues to be traversed;

[0047] When the ellipticity of the light spot is greater than the preset threshold, the movement position of the first slide 1 is stopped, and the radius of the current light spot is obtained through the beam quality analyzer 2 as the light spot radius corresponding to the optical fiber 4 to be tested at the first preset axial distance.

[0048] Preferably, obtaining the mode field diameter of the optical fiber 4 to be tested according to the spot radius and the corresponding axial distance corresponding to the optical fiber 4 to be tested at different axial distance positions specifically includes:

[0049] The calculation equation for the mode field diameter is:

[0050]

[0051] Among them, z1 is the first preset axial distance, z2 is the second preset axial distance, λ is the wavelength of the light signal emitted by the optical fiber 4 to be tested, ω0 is the mode field radius of the optical fiber 4 to be tested, 2ω0 is the mode field diameter of the optical fiber 4 to be tested, ω1 is the spot radius corresponding to the optical fiber 4 to be tested at the first preset axial distance, and ω2 is the spot radius corresponding to the optical fiber 4 to be tested at the second preset axial distance.

[0052] The present invention provides an automated measurement device and method for the mode field diameter of an optical fiber, comprising: a first slide 1, a beam quality analyzer 2, and a base 3, wherein the first slide 1 and the beam quality analyzer 2 are sequentially arranged on the base 3; the first slide 1 is used to set an optical fiber 4 to be measured, and drive the optical fiber 4 to be measured to move or rotate in different directions, so as to adjust the axial distance between the end face of the optical fiber 4 to be measured and the beam quality analyzer 2, and to adjust the position and ellipticity of a light spot emitted by the optical fiber 4 to be measured on the beam quality analyzer 2, so as to accurately measure the light spot emitted by the optical fiber 4 to be measured at different axial distance positions through the beam quality analyzer 2, obtain the light spot radius corresponding to the optical fiber 4 to be measured at different axial distance positions, obtain the mode field diameter of the optical fiber 4 to be measured according to the light spot radius corresponding to the optical fiber 4 to be measured at different axial distance positions and the corresponding axial distance, and improve the measurement accuracy of the mode field diameter of the optical fiber 4 to be measured by adjusting the light spot ellipticity by the first slide 1. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] To more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. Those skilled in the art can also derive other drawings based on these drawings without inventive effort.

[0054] Figure 1 1 is a schematic structural diagram of an automatic measurement device for optical fiber mode field diameter provided by an embodiment of the present invention;

[0055] Figure 2 1 is a schematic structural diagram of another automatic optical fiber mode field diameter measurement device provided by an embodiment of the present invention;

[0056] Figure 3 Schematic diagram of the structure of another automatic measurement device for optical fiber mode field diameter provided by an embodiment of the present invention;

[0057] Figure 4 Schematic diagram of the structure of another automatic measurement device for optical fiber mode field diameter provided by an embodiment of the present invention;

[0058] Figure 5 Schematic diagram of the structure of another automatic measurement device for optical fiber mode field diameter provided by an embodiment of the present invention;

[0059] Figure 6 This is a flow chart of a method for automatically measuring the mode field diameter of an optical fiber provided by an embodiment of the present invention;

[0060] Figure 7 This is a flow chart of another method for automatically measuring the mode field diameter of an optical fiber provided by an embodiment of the present invention;

[0061] The accompanying drawings are numbered as follows:

[0062] First slide 1; first base 11; first horizontal moving assembly 12; first X-axis slide 121; first Y-axis slide 122; first vertical moving member 13; first vertical axial rotation member 14; first horizontal axial rotation member 15; clamp 16; beam quality analyzer 2; base 3; optical fiber to be tested 4; second slide 5; second base 51; second horizontal moving assembly 52; second X-axis slide 521; second Y-axis slide 522; second horizontal axial rotation member 53. DETAILED DESCRIPTION

[0063] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0064] In the description of the present invention, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present disclosure and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present disclosure.

[0065] In the description of the present invention, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present disclosure, unless otherwise specified, "multiple" means two or more. In addition, for example, the description may also use the method of adding "A" and "B" at the end to describe the same type of nouns as two independent individuals. In this case, the corresponding features defined as "A" and "B" are only used to distinguish the description purposes of the same type of individuals, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated.

[0066] As used herein, "about," "substantially," or "approximately" includes the stated value and an average value that is within an acceptable range of deviation from the particular value as determined by one of ordinary skill in the art taking into account the measurement in question and the errors associated with the measurement of the particular quantity, i.e., the limitations of the measurement system.

[0067] Unless the context requires otherwise, throughout the specification and claims, the term "including" is to be interpreted as meaning open inclusion, that is, "including, but not limited to". In the description of the specification, the terms "one embodiment", "some embodiments", "exemplary embodiments", "example", "specific example" or "some examples" and the like are intended to indicate that the specific features, structures, materials or characteristics associated with the embodiment or example are included in at least one embodiment or example of the present disclosure. The schematic representation of the above terms does not necessarily refer to the same embodiment or example. In addition, the specific features, structures, materials or characteristics may be included in any one or more embodiments or examples in any appropriate manner, that is, although they may be carried in the embodiments or examples of the above terms due to reasons such as the order and position of appearance, it is not limited to that they can be carried in combination by one embodiment or example.

[0068] In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0069] Embodiment 1:

[0070] Embodiment 1 of the present invention provides an automated optical fiber mode field diameter measurement device, comprising: a first slide 1, a beam quality analyzer 2, and a base 3, wherein:

[0071] The first slide 1 and the beam quality analyzer 2 are sequentially arranged on the base 3; the first slide 1 is used to set the optical fiber 4 to be tested, and drive the optical fiber 4 to be tested to move horizontally, vertically, rotate vertically and rotate horizontally, so as to adjust the axial distance between the end face of the optical fiber 4 to be tested and the beam quality analyzer 2, and adjust the position and ellipticity of the light spot emitted by the optical fiber 4 to be tested on the beam quality analyzer 2.

[0072] The beam quality analyzer 2 is used to measure the light spot emitted by the optical fiber 4 to be tested at different axial distance positions to obtain the light spot radius corresponding to the optical fiber 4 to be tested at different axial distance positions, and obtain the mode field diameter of the optical fiber 4 to be tested based on the light spot radius corresponding to the optical fiber 4 to be tested at different axial distance positions and the corresponding axial distance.

[0073] In this embodiment, when the optical fiber to be tested 4 is set on the first slide 1, one end of the optical fiber to be tested 4 is used to connect to the light source, and the other end of the optical fiber to be tested 4 is used to emit a light signal. The end face of the light-emitting end of the optical fiber to be tested 4 faces the photosensitive surface of the beam quality analyzer 2. The light signal emitted by the optical fiber to be tested 4 will hit the beam quality analyzer 2 and present a corresponding light spot. The beam quality analyzer 2 is used to detect the radius of the light spot.

[0074] In this embodiment, the first slide 1 includes a plurality of movable parts arranged along different directions, and each movable part can be moved in the corresponding direction by a corresponding stepping motor, thereby driving the optical fiber 4 to be tested to adjust its position in different directions, wherein the vertical axial rotation can be a rotation around an axis perpendicular to the horizontal plane, and the horizontal axial rotation can be a rotation around an axis parallel to the horizontal plane.

[0075] The axial distance can be the vertical distance from the end face of the light-emitting end of the optical fiber 4 to be tested to the surface of the beam quality analyzer 2. When actually measuring the mode field diameter of the optical fiber 4 to be tested, it is necessary to place the optical fiber 4 to be tested at two different axial distances from the beam quality analyzer 2, and measure the spot radius of the optical fiber 4 to be tested at the two axial distances respectively. According to the two spot radii and the difference between the two axial distances, an equation is constructed to accurately obtain the mode field diameter of the optical fiber 4 to be tested. In the above process, the axial distance between the optical fiber 4 to be tested and the beam quality analyzer 2 needs to be adjusted by the first slide 1. Furthermore, when the beam quality analyzer 2 measures the spot radius, the spot also needs to meet the ellipticity requirements. In order to ensure the accuracy of the spot radius measurement, it is necessary to ensure that the spot is closer to a circle as much as possible. Therefore, it is necessary to adjust the position and angle of the optical fiber 4 to be tested, so as to ensure that the light spot of the light signal emitted by the optical fiber 4 to be tested and hitting the beam quality analyzer 2 is closer to a circle. In this embodiment, the relative position between the optical fiber 4 to be tested and the beam quality analyzer 2, as well as the incident angle of the outgoing light of the optical fiber 4 to be tested on the surface of the beam quality analyzer 2 are adjusted by adjusting the various movable parts on the first slide 1, so that the light spot meets the ellipticity requirements. On this basis, the radius of the light spot is measured to ensure the accuracy of subsequent calculations.

[0076] In this embodiment, the first slide 1 can be controlled by the host, and the beam quality analyzer 2 can also be connected to the host through a data cable to upload and feedback the measurement results. The host controls the various moving parts of the first slide 1 based on the measurement results, thereby realizing the automated measurement of the mode field diameter of the optical fiber 4 to be measured.

[0077] Furthermore, in this embodiment, since the horizontal movement, vertical movement, vertical axial rotation, and horizontal axial rotation of the optical fiber 4 to be tested need to be achieved through the first slide 1, a corresponding moving part is required in each direction. Therefore, this embodiment also involves the following design:

[0078] like Figure 2 As shown, the first slide 1 specifically includes: a first base 11, a first horizontal moving assembly 12, a first vertical moving member 13, a first vertical axial rotating member 14, a first horizontal axial rotating member 15 and a clamp 16, wherein:

[0079] The first base 11 is located at the bottom end of the first slide 1, and the first horizontal moving component 12 is arranged at the upper end of the first base 11. The first horizontal moving component 12 is used for moving in the X-axis direction and the Y-axis direction (the coordinate system in the figure is the X-axis direction, the Y-axis direction and the Z-axis direction). A vertical guide rail is arranged on the side of the first horizontal moving component 12; the first vertical moving member 13 is arranged on the side of the first horizontal moving component 12 and is slidably connected to the vertical guide rail; a first arc surface is provided on the first vertical moving member 13, and a vertical axial arc guide rail is provided on the first arc surface; the first vertical axial rotating member 14 is provided on the first arc surface and is slidably connected to the vertical axial arc guide rail ( Figure 2 The arrow of the position of the first vertical axial rotating member 14 is the sliding direction), the upper end of the first vertical axial rotating member 14 is provided with a second arc surface, and the second arc surface is provided with a horizontal axial arc guide rail; the first horizontal axial rotating member 15 is provided on the second arc surface and is slidably connected with the horizontal axial arc guide rail ( Figure 2 The arrow indicating the position of the first horizontal axial rotating member 15 is the sliding direction); the clamp 16 is provided on the first horizontal axial rotating member 15, and the clamp 16 is used to fix the optical fiber 4 to be tested.

[0080] The first horizontal moving assembly 12 includes a first X-axis slide 121 and a first Y-axis slide 122, wherein: the first base 11 is provided with an X-axis slide rail (ie, Figure 2 The first X-axis slide 121 is provided on the first base 11 and is slidably connected to the X-axis slide rail; the first X-axis slide 121 is provided with a Y-axis slide rail (i.e., connected to the first X-axis slide rail). Figure 2 The guide rail is parallel to the Y-axis direction of the central coordinate system, and the arrow next to the first Y-axis slide 122 in the figure indicates the sliding direction), the first Y-axis slide 122 is arranged on the first X-axis slide 121 and is slidably connected to the first Y-axis slide 122; the side of the first Y-axis slide 122 is provided with the vertical guide rail, and the first vertical moving member 13 is arranged on the side of the first horizontal moving component 12 and is slidably connected to the vertical guide rail.

[0081] In this embodiment, the X-axis direction is the direction parallel to the axial direction on a horizontal plane, and the Y-axis direction is the direction perpendicular to the X-axis direction on a horizontal plane. The first X-axis slide 121 and the first Y-axis slide 122 are used to achieve horizontal movement, and the first vertical moving member 13 is used to achieve vertical movement. By adjusting the first X-axis slide 121, the first Y-axis slide 122, and the first vertical moving member 13, the light spot is ensured to be projected at a specified position on the beam quality analyzer 2. The first vertical axial rotation member 14 and the first horizontal axial rotation member 15 are used to adjust the incident angle of the optical signal emitted by the optical fiber 4 under test on the beam quality analyzer 2. When the incident angle approaches 90 degrees, the light spot becomes more circular and the ellipticity increases. When the difference between the incident angle and 90 degrees increases, the light spot becomes more elliptical and the ellipticity decreases. Therefore, by adjusting the first vertical axial rotation member 14 and the first horizontal axial rotation member 15, the light spot of the optical signal emitted by the optical fiber 4 under test can meet the ellipticity requirements.

[0082] In this embodiment, the above-mentioned adjustment of the first slide 1 can be controlled by the host. The host controls the first slide 1 to traverse various positions in the horizontal direction, vertical direction, horizontal axis and vertical axis. While traversing, the beam quality analyzer 2 is used to obtain the ellipticity of the light spot. When the ellipticity of the light spot meets the requirements, the traversal is stopped, and the corresponding spot radius at this time is measured to obtain the radius of the light spot corresponding to the axial distance.

[0083] In this embodiment, Figure 2 The automated optical fiber mode field diameter measurement device also includes a second slide 5, wherein: the second slide 5 is arranged on the base 3, and the beam quality analyzer 2 is arranged on the second slide 5; the second slide 5 is used to drive the beam quality analyzer 2 to move horizontally and rotate horizontally axially to adjust the initial relative position between the beam quality analyzer 2 and the optical fiber 4 to be measured.

[0084] like Figure 4 The second slide 5 specifically includes: a second base 51, a second horizontal moving assembly 52, and a second horizontal axial rotating member 53, wherein: the second base 51 is arranged on the base 3, the second horizontal moving assembly 52 is arranged on the upper end of the second base 51, the second horizontal moving assembly 52 is used to move in the X-axis direction and the Y-axis direction, the second horizontal moving assembly 52 is provided with a third arc surface, and the third arc surface is provided with a horizontal axial arc guide rail; the second horizontal axial rotating member 53 is provided on the third arc surface and is slidably connected to the horizontal axial arc guide rail ( Figure 4The arrow indicating the position of the second horizontal axial rotating member 53 is the sliding direction); the beam quality analyzer 2 is arranged on the second horizontal axial rotating member 53.

[0085] like Figure 5 As shown, the second horizontal moving assembly 52 includes a second X-axis slide 521 and a second Y-axis slide 522, wherein: a Y-axis slide rail is provided on the second base 51, and the second Y-axis slide 522 is provided on the second base 51 and is slidably connected to the Y-axis slide rail (i.e., Figure 5 The second Y-axis slide 522 is provided with an X-axis slide rail, and the second X-axis slide 521 is provided on the second Y-axis slide 522 and is slidably connected to the second X-axis slide 521 (i.e., connected to the second X-axis slide 521). Figure 5 The guide rail is parallel to the X-axis direction of the coordinate system, and the arrow next to the second X-axis slide 521 in the figure indicates the sliding direction); the second X-axis slide 521 is provided with the third arc surface, and the third arc surface is provided with a horizontal axial arc guide rail. The second horizontal axial rotating member 53 is provided on the third arc surface and is slidably connected with the horizontal axial arc guide rail.

[0086] In this embodiment, the second X-axis slide 521, the second Y-axis slide 522, and the second horizontal axial rotation member 53 are all manually adjustable slides, and those skilled in the art can directly adjust them through manual operation. By manually adjusting the second X-axis slide 521 and the second Y-axis slide 522, the relative position between the optical fiber 4 to be tested and the beam quality analyzer 2 is roughly adjusted. By manually adjusting the second horizontal axial rotation member 53, the angle of incidence of the optical signal emitted by the optical fiber 4 to be tested on the beam quality analyzer 2 is roughly adjusted to approximately 90 degrees. After the above adjustments are completed, the host computer controls the first slide 1 for fine adjustment, thereby improving adjustment efficiency while maintaining the required adjustment accuracy.

[0087] In actual use, the second X-axis slide 521, the second Y-axis slide 522, and / or the second horizontal axial rotation member 53 are usually manually adjusted first to coarsely adjust the optical fiber 4 to be tested and the beam quality analyzer 2 to their approximate positions. The host computer then adjusts the first slide 1 until the light spot of the optical fiber 4 to be tested hits the designated position on the beam quality analyzer 2 and meets the ellipticity requirements, thereby achieving fine adjustment. In this process, fine adjustment requires higher accuracy but is slower, while coarse adjustment requires lower accuracy and is more efficient. Therefore, coarse adjustment to the approximate position can greatly improve adjustment efficiency, followed by fine adjustment to increase accuracy.

[0088] Example 2:

[0089] This embodiment provides an automatic measurement method for optical fiber mode field diameter based on embodiment 1, which is used in the automatic measurement device for optical fiber mode field diameter. Figure 6 As shown, the method flow includes:

[0090] In step 101 , the optical fiber 4 to be tested is placed on the first slide 1 , and the optical fiber 4 to be tested is connected to a light source.

[0091] In step 102, the first slide 1 is adjusted to adjust the relative position between the optical fiber to be tested 4 and the beam quality analyzer 2, and the light spots emitted by the optical fiber to be tested 4 at different axial distance positions are measured by the beam quality analyzer 2 to obtain the light spot radius corresponding to the optical fiber to be tested 4 at different axial distance positions.

[0092] In step 103 , the mode field diameter of the optical fiber 4 to be tested is obtained according to the spot radius and the corresponding axial distance corresponding to the optical fiber 4 to be tested at different axial distance positions.

[0093] In this embodiment, it is necessary to measure the spot of the light signal emitted by the optical fiber 4 to be tested at at least two different axial distance positions. An equation is constructed and solved based on the spot radius obtained from the two measurements and the difference between the two corresponding axial distances to obtain the mode field diameter of the optical fiber 4 to be tested. Therefore, this embodiment also involves the following design:

[0094] The first slide 1 is adjusted to adjust the relative position between the optical fiber 4 to be tested and the beam quality analyzer 2, and the beam quality analyzer 2 is used to measure the light spots emitted by the optical fiber 4 to be tested at different axial distances to obtain the light spot radii corresponding to the optical fiber 4 to be tested at different axial distances. The specific method steps corresponding to the above process are as follows: Figure 7 Shown, including:

[0095] In step 201 , the axial position of the first slide 1 or the axial position of the beam quality analyzer 2 is adjusted so that the end face of the optical fiber 4 to be tested and the beam quality analyzer 2 are at a first preset axial distance.

[0096] In step 202 , the first slide 1 is adjusted and the beam quality analyzer 2 is used to obtain the spot radius corresponding to the optical fiber 4 to be tested at the first preset axial distance.

[0097] In step 203 , the axial position of the first slide 1 or the axial position of the beam quality analyzer 2 is adjusted so that the end face of the optical fiber 4 to be tested and the beam quality analyzer 2 are at a second preset axial distance.

[0098] In step 204 , the first slide 1 is adjusted and the beam quality analyzer 2 is used to obtain the spot radius corresponding to the optical fiber 4 to be tested at the second preset axial distance.

[0099] Furthermore, the adjusting of the first slide 1 and obtaining the spot radius corresponding to the optical fiber 4 to be tested at the first preset axial distance by the beam quality analyzer 2 specifically include:

[0100] In step 301 , the moving positions of the first slide 1 are traversed, and the ellipticity of the light spot corresponding to the optical fiber 4 to be tested at a first preset axial distance is obtained by the beam quality analyzer 2 .

[0101] In step 302, it is determined in real time whether the ellipticity of the light spot is greater than a preset threshold.

[0102] In step 303 , when the ellipticity of the light spot is less than or equal to the preset threshold, the moving position of the first slide 1 continues to be traversed.

[0103] In step 304, when the ellipticity of the light spot is greater than the preset threshold, the movement position of the first slide 1 is stopped, and the radius of the current light spot is obtained through the beam quality analyzer 2 as the light spot radius corresponding to the optical fiber 4 to be tested at the first preset axial distance.

[0104] It should be noted that even if the ellipticity of the light spot meets the requirements by traversing the first slide 1 and the light spot profile is closer to a circle, the light spot is still elliptical in the end. In order to ensure that the measured light spot radius is closer to the theoretical accuracy in subsequent calculations, the maximum diameter and minimum diameter of the light spot are obtained respectively by the beam quality analyzer 2, and the average light spot radius is calculated by the maximum diameter and minimum diameter. The average light spot radius is the radius corresponding to when the light spot is regarded as a circle. The average light spot radius is brought into the subsequent calculation to improve the accuracy of the subsequent calculation. The calculation formula of the light spot radius is:

[0105] ω x =(d min +d max ) / 4;

[0106] Among them, ω x is the radius corresponding to the light spot being considered as a circle, d min is the minimum diameter of the light spot, d max is the maximum diameter of the light spot.

[0107] According to the characteristics of Gaussian beam, the relationship between Rayleigh distance is:

[0108]

[0109] The relationship between the spot radius and the axial distance is:

[0110]

[0111] The calculation equation for the mode field diameter is:

[0112]

[0113] Wherein, z1 is the first preset axial distance, z2 is the second preset axial distance, ω(z) is the mode field diameter of the optical fiber 4 under test corresponding to different axial distances, λ is the wavelength of the light signal emitted by the optical fiber 4 under test, ω0 is the mode field radius of the optical fiber 4 under test, 2ω0 is the mode field diameter of the optical fiber 4 under test, ω1 is the spot radius corresponding to the optical fiber 4 under test at the first preset axial distance, and ω2 is the spot radius corresponding to the optical fiber 4 under test at the second preset axial distance. By solving the calculation equation, the mode field radius of the optical fiber 4 under test can be obtained, and thus the mode field diameter of the optical fiber 4 under test can be obtained.

[0114] In this embodiment, z1-z2 can be set by those skilled in the art, wherein z1-z2 can be 5000um-6000um.

[0115] In this embodiment, the optical fiber 4 to be tested is adjusted by the first slide 1, driving the optical fiber 4 to be tested to move horizontally, vertically, rotate vertically and horizontally, thereby ensuring that the ellipticity of the light spot corresponding to the optical fiber 4 to be tested meets the requirements, and ensuring that the radius corresponding to the light spot meets the requirements, and then the radius of the light spot is accurately obtained by the beam quality analyzer 2. The above design ensures the accuracy of the obtained light spot radius, and then ensures the accuracy of subsequent calculations, thereby obtaining a relatively accurate mode field diameter of the optical fiber 4 to be tested.

[0116] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. An automated optical fiber mode field diameter measurement device, characterized in that: include: A first slide (1), a beam quality analyzer (2) and a base (3), wherein: The first slide (1) and the beam quality analyzer (2) are sequentially arranged on the base (3); The first slide (1) is used to set the optical fiber to be tested (4) and drive the optical fiber to be tested (4) to move horizontally, move vertically, rotate vertically and rotate horizontally, so as to adjust the axial distance between the end face of the optical fiber to be tested (4) and the beam quality analyzer (2), and to adjust the position and ellipticity of the light spot emitted by the optical fiber to be tested (4) on the beam quality analyzer (2); The beam quality analyzer (2) is used to measure the light spots emitted by the optical fiber (4) to be tested at different axial distance positions to obtain the light spot radius corresponding to the optical fiber (4) to be tested at different axial distance positions, and obtain the mode field diameter of the optical fiber (4) to be tested based on the light spot radius corresponding to the optical fiber (4) to be tested at different axial distance positions and the corresponding axial distance; The first slide (1) specifically comprises: a first base (11), a first horizontal moving component (12), a first vertical moving member (13), a first vertical axial rotating member (14), a first horizontal axial rotating member (15) and a clamp (16), wherein: The first base (11) is located at the bottom end of the first slide (1), the first horizontal moving component (12) is arranged at the upper end of the first base (11), the first horizontal moving component (12) is used for moving in the X-axis direction and the Y-axis direction, and a vertical guide rail is arranged on the side of the first horizontal moving component (12); The first vertical moving member (13) is arranged on a side surface of the first horizontal moving assembly (12) and is slidably connected to the vertical guide rail; The first vertical moving member (13) is provided with a first arc surface, and a vertical axial arc guide rail is provided on the first arc surface; The first vertical axial rotating member (14) is arranged on the first arc surface and is slidably connected to the vertical axial arc guide rail. The upper end of the first vertical axial rotating member (14) is provided with a second arc surface, and the second arc surface is provided with a horizontal axial arc guide rail. The first horizontal axial rotating member (15) is arranged on the second arc surface and is slidably connected to the horizontal axial arc guide rail; The clamp (16) is arranged on the first horizontal axial rotating member (15), and the clamp (16) is used to fix the optical fiber to be tested (4).

2. The optical fiber mode field diameter automatic measuring device according to claim 1, characterized in that: The first horizontal movement assembly (12) comprises a first X-axis slide (121) and a first Y-axis slide (122), wherein: An X-axis slide rail is provided on the first base (11); the first X-axis slide table (121) is provided on the first base (11) and is slidably connected to the X-axis slide rail; A Y-axis slide rail is provided on the first X-axis slide (121); the first Y-axis slide (122) is provided on the first X-axis slide (121) and is slidably connected to the first Y-axis slide (122); The vertical guide rail is provided on the side of the first Y-axis slide (122), and the first vertical moving member (13) is provided on the side of the first horizontal moving component (12) and is slidably connected to the vertical guide rail.

3. The optical fiber mode field diameter automatic measuring device according to claim 1, characterized in that: The optical fiber mode field diameter automatic measuring device further comprises a second slide (5), wherein: The second slide (5) is arranged on the base (3), and the beam quality analyzer (2) is arranged on the second slide (5); The second slide (5) is used to drive the beam quality analyzer (2) to move in the horizontal direction and rotate in the horizontal axial direction, so as to adjust the initial relative position between the beam quality analyzer (2) and the optical fiber to be measured (4).

4. The optical fiber mode field diameter automatic measuring device according to claim 3, characterized in that: The second slide (5) specifically comprises: a second base (51), a second horizontal moving assembly (52) and a second horizontal axial rotating member (53), wherein: The second base (51) is arranged on the base (3), the second horizontal moving assembly (52) is arranged on the upper end of the second base (51), the second horizontal moving assembly (52) is used for moving in the X-axis direction and the Y-axis direction, and the second horizontal moving assembly (52) is provided with a third arc surface, and the third arc surface is provided with a horizontal axial arc guide rail; The second horizontal axial rotating member (53) is arranged on the third arc surface and is slidably connected to the horizontal axial arc guide rail; The beam quality analyzer (2) is arranged on the second horizontal axial rotating member (53).

5. The optical fiber mode field diameter automatic measuring device according to claim 4, characterized in that: The second horizontal moving assembly (52) comprises a second X-axis slide (521) and a second Y-axis slide (522), wherein: A Y-axis slide rail is provided on the second base (51); the second Y-axis slide table (522) is provided on the second base (51) and is slidably connected to the Y-axis slide rail; An X-axis slide rail is provided on the second Y-axis slide (522), and the second X-axis slide (521) is provided on the second Y-axis slide (522) and is slidably connected to the second X-axis slide (521); The second X-axis slide (521) is provided with the third arc surface, the third arc surface is provided with a horizontal axial arc guide rail, and the second horizontal axial rotating member (53) is provided on the third arc surface and is slidably connected to the horizontal axial arc guide rail.

6. A method for automatically measuring the mode field diameter of an optical fiber, for use in the automatic measurement device for the mode field diameter of an optical fiber according to any one of claims 1 to 5, characterized in that: include: The optical fiber to be tested (4) is placed on the first slide (1), and the optical fiber to be tested (4) is connected to the light source; The first slide (1) is adjusted to adjust the relative position between the optical fiber to be tested (4) and the beam quality analyzer (2), and the beam quality analyzer (2) is used to measure the light spots emitted by the optical fiber to be tested (4) at different axial distance positions, so as to obtain the light spot radii corresponding to the optical fiber to be tested (4) at different axial distance positions; The mode field diameter of the optical fiber (4) to be tested is obtained according to the spot radius corresponding to the optical fiber (4) to be tested at different axial distance positions and the corresponding axial distance.

7. The method for automatically measuring the optical fiber mode field diameter according to claim 6, wherein: The method comprises adjusting the relative position between the optical fiber to be tested (4) and the beam quality analyzer (2) by adjusting the first slide (1), and measuring the light spots emitted by the optical fiber to be tested (4) at different axial distance positions by the beam quality analyzer (2) to obtain the light spot radii corresponding to the optical fiber to be tested (4) at different axial distance positions, specifically comprising: By adjusting the axial position of the first slide (1) or adjusting the axial position of the beam quality analyzer (2), the end face of the optical fiber to be tested (4) and the beam quality analyzer (2) are at a first preset axial distance; Adjusting the first slide (1) and obtaining the spot radius corresponding to the optical fiber to be tested (4) at a first preset axial distance through the light beam quality analyzer (2); By adjusting the axial position of the first slide (1) or adjusting the axial position of the beam quality analyzer (2), the end face of the optical fiber to be tested (4) and the beam quality analyzer (2) are at a second preset axial distance; The first slide (1) is adjusted and the light spot radius corresponding to the optical fiber to be tested (4) at the first preset axial distance is obtained through the light beam quality analyzer (2).

8. The method for automatically measuring the optical fiber mode field diameter according to claim 7, wherein: The adjusting of the first slide (1) and obtaining the spot radius corresponding to the optical fiber to be tested (4) at the first preset axial distance through the light beam quality analyzer (2) specifically include: Traversing the moving positions of the first slide (1), and obtaining the ellipticity of the light spot corresponding to the optical fiber to be tested (4) at a first preset axial distance through the beam quality analyzer (2); Determining in real time whether the ellipticity of the light spot is greater than a preset threshold; When the ellipticity of the light spot is less than or equal to the preset threshold, the moving position of the first slide (1) continues to be traversed; When the ellipticity of the light spot is greater than the preset threshold, the movement position of the first slide (1) is stopped, and the radius of the current light spot is obtained through the beam quality analyzer (2) as the light spot radius corresponding to the optical fiber to be tested (4) at the first preset axial distance.

9. The method for automatically measuring the optical fiber mode field diameter according to claim 7, wherein: The method of obtaining the mode field diameter of the optical fiber (4) to be tested according to the spot radius corresponding to the optical fiber (4) to be tested at different axial distance positions and the corresponding axial distance specifically includes: The calculation equation for the mode field diameter is: ； in, is the first preset axial distance, is the second preset axial distance, is the wavelength of the optical signal emitted by the optical fiber (4) to be tested, is the mode field radius of the optical fiber (4) to be tested, 2 is the mode field diameter of the optical fiber (4) to be tested, is the spot radius corresponding to the optical fiber (4) to be tested at the first preset axial distance, The light spot radius corresponding to the optical fiber (4) to be tested at the second preset axial distance.

Images