A fiber collimator capable of stable positioning by means of slope matching

Abstract

This utility model discloses a fiber optic collimator that achieves stable positioning using a beveled surface, relating to the field of fiber optic collimator technology. It includes a collimator body, a fiber optic inlet, an adjustment cap, an adjustment spring, a lens holder, a top ring, and a lens assembly. One or both ends of the lens holder are beveled, forming a ramp-type engagement structure with the adjustment spring and / or the top ring. This generates a beveled force deviating from the axis of the collimator body, pressing the outer wall of the lens holder against the inner wall of the collimator body. A locking assembly is provided on the collimator body, opposite to the contact position of the lens holder and the collimator body, for locking the lens holder. This invention effectively solves the problems of optical path offset, jumps, and inability to accurately restore position that occur when adjusting the focal length in existing fiber optic collimators. It significantly improves the adjustment accuracy and stability of the fiber optic collimator, ensuring that the beam direction remains unchanged in different adjustment and locking states, thereby improving the efficiency and accuracy of optical signal transmission.

Description

Technical Field

[0001] This utility model relates to the field of fiber optic collimator technology, and more specifically to a fiber optic collimator that achieves stable positioning by utilizing inclined planes. Background Technology

[0002] A fiber optic collimator is a device used to couple laser light from free space into an optical fiber, or to output laser light from an optical fiber as an adjustable collimated beam for transmission to the outside.

[0003] A free-space fiber collimator is an optical device used to construct a spatial optical path, converting a diverging beam emitted from an optical fiber into a parallel beam. It is widely used in optical communication, laser processing, laser measurement, and optical laboratories. In these applications, the performance of the fiber collimator directly affects the efficiency and accuracy of optical signal transmission. Typically, based on the fiber's NA (nanoscale range), core mode field diameter, and the wavelength of the transmitted light, different focal length lenses are selected to output collimated light of the desired spot size. Collimated light refers to laser spot size that remains approximately constant over long distances; this is the most widespread application. In addition, users can adjust the distance between the lens and the fiber core to achieve laser beam contraction and expansion, placing the beam waist at different distances to fulfill specific optical requirements.

[0004] Fiber optic collimators operate based on the refraction of optical lenses. By adjusting the position and angle of the lenses, the divergence angle or collimation state of the emitted beam can be changed to meet the needs of different applications. Their main performance indicators include the collimation (divergence angle) of the emitted beam, insertion loss, and optical alignment accuracy. These indicators directly affect the quality of optical signal transmission. In high-precision applications, fiber optic collimators with low insertion loss and high collimation are particularly needed to ensure signal integrity and accuracy.

[0005] Fiber optic collimators are crucial components connecting optical fibers to other optical elements, such as lasers and detectors. Their primary task is to introduce optical signals from external systems into the fiber. During this process, the fiber optic collimator needs excellent alignment capabilities and low-loss transmission characteristics. Therefore, the fiber optic collimator requires adjustable focal length, as the divergence characteristics of laser light input in free space are unknown; thus, adjusting the coupler's focal length is necessary to improve coupling efficiency. Coupling efficiency and alignment accuracy are important indicators for evaluating the performance of fiber optic collimators. High-quality couplers ensure minimal light loss while guaranteeing signal stability and interference resistance. Modern fiber optic collimators continuously innovate in material selection, processing technology, and structural design to adapt to the increasingly complex demands of optical communication applications. Since fiber optic collimators and optical fiber collimators each play a key role in the optical system, their performance directly affects the efficiency and reliability of the entire optical path system. Especially in optical communication, accurate collimation and efficient coupling are fundamental to achieving high-quality signal transmission.

[0006] Currently available rotary adjustable-focus fiber optic collimator devices all suffer from several unresolved technical challenges. The first problem lies in the fact that during the process of adjusting the front and rear focal lengths using the rotary adjustment device, the emitted laser inevitably deviates from the ideal transmission direction (central axis of symmetry). This problem is caused by multiple factors, including gaps in the track design and abrupt changes in the direction of the spring force. In addition, factors such as the flatness of the contact surface and the matching of the main housing and lens assembly can also lead to laser emission deviation and system instability.

[0007] Another very serious problem is that during the process of moving the focal length back and forth, it is impossible to perfectly restore the previous state. For example, if we keep the focal length at 7.5mm, and when we move the focal length back and forth to return to the theoretical 7.5mm position, we find that due to the above-mentioned unstable factors, the light spot inevitably deviates upward or downward. That is, the light spot points differently at the same focal length, and the previous adjustment position cannot be reproduced.

[0008] The third type of problem is that when we want to lock the position of the lens holder and lens group (by tightening the screws), it will cause the lens to shift relative to the main body and the central axis, thus affecting its use. That is, there will be a jump shift in the xy direction (two perpendicular directions in the radial direction) after locking and before locking. Utility Model Content

[0009] In view of this, the present invention provides an optical fiber collimator that achieves stable positioning by using inclined planes, aiming to solve the above-mentioned technical problems.

[0010] To achieve the above objectives, the present invention adopts the following technical solution:

[0011] A fiber optic collimator that achieves stable positioning using inclined planes includes: a collimator body, one end of which has a fiber optic inlet, and the other end of which is threadedly connected to an adjustment cap. The inner cavity of the collimator body is provided with an adjustment spring, a lens holder, and a top ring that abut against each other, arranged sequentially from the fiber optic inlet toward the adjustment cap. A lens assembly is provided inside the lens holder. The position of the lens assembly can be adjusted by turning the adjustment cap.

[0012] One or both ends of the lens holder are set as bevels, so that the lens holder and the adjusting spring and / or the top ring form a ramp-type fit structure. Due to the bevel setting of the lens holder, the adjusting spring or the top ring at either end of the lens holder forms an oblique force relative to the lens holder that deviates from the axis of the collimator body, thereby causing an outer side wall of the lens holder to be pressed against the inner side wall of the collimator body.

[0013] The collimator body is provided with a locking component for locking the lens holder, and the locking component is opposite to the contact position of the lens holder and the collimator body.

[0014] Through the above technical solution, this utility model, by using the inclined surface design of the lens holder, causes the adjusting spring or top ring to generate an oblique force on the lens holder that deviates from the axis of the collimator body. This causes the outer wall of the lens holder to be pressed against the inner wall of the collimator body, and the locking assembly further fixes the position of the lens holder. This effectively solves the problems of optical path offset, jump, and inability to accurately restore the position that occur when adjusting the focal length in the existing fiber optic collimator. It significantly improves the adjustment accuracy and stability of the fiber optic collimator, ensures that the light spot direction remains unchanged in different adjustment and locking states, and improves the efficiency and accuracy of optical signal transmission.

[0015] Preferably, in the fiber optic collimator that utilizes inclined surfaces to achieve stable positioning, when the end of the lens holder facing the top ring is inclined, the end face of the top ring is an inclined surface that matches the inclination of the inclined surface of the lens holder.

[0016] Preferably, in the above-mentioned fiber optic collimator that uses inclined planes to achieve stable positioning, the inclination angle of the inclined plane of the lens holder is 3-25°.

[0017] Preferably, in the above-mentioned fiber optic collimator that utilizes inclined planes for stable positioning, the locking assembly includes a set screw that is threadedly connected to the side wall of the collimator body.

[0018] Preferably, in the above-mentioned fiber optic collimator that uses inclined planes to achieve stable positioning, there are multiple top wires, which are arranged along the axial direction of the collimator body.

[0019] Preferably, in the above-mentioned fiber collimator that uses inclined planes to achieve stable positioning, a V-shaped groove corresponding to the top wire is axially formed on the outer wall of the lens holder.

[0020] Preferably, in the above-mentioned fiber optic collimator that utilizes inclined planes for stable positioning, the set screw is a wave screw.

[0021] Preferably, in the fiber optic collimator that utilizes inclined planes for stable positioning, the two sides of the top sphere of the wave screw symmetrically abut against the two side walls of the V-groove.

[0022] Preferably, in the fiber optic collimator that utilizes inclined surfaces to achieve stable positioning, when both ends of the lens holder are provided with inclined surfaces, the inclined surfaces on both sides are symmetrically arranged.

[0023] Preferably, in the above-mentioned fiber optic collimator that uses inclined surfaces to achieve stable positioning, the inclined surface of the lens holder is concave inward to form an arc shape.

[0024] As can be seen from the above technical solution, compared with the prior art, this utility model discloses a fiber optic collimator that achieves stable positioning using a beveled surface. Through the beveled design of the lens holder and the optimization of the locking assembly, it effectively solves the problems of optical path offset, jumps, and inaccurate position restoration that occur in existing fiber optic collimators when adjusting the focal length. This significantly improves the adjustment accuracy and stability of the fiber optic collimator, ensuring that the light spot direction remains unchanged under different adjustment and locking states. Simultaneously, by optimizing the structure of the locking assembly and lens holder, the jump phenomenon during locking is further reduced, improving the efficiency and accuracy of optical signal transmission. It is suitable for various fiber optic coupling requirements and has high practicality and innovation. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0026] Figure 1 The attached figure is a cross-sectional view of an existing fiber optic collimator;

[0027] Figure 2 The attached diagram is an exploded view of an existing fiber optic collimator.

[0028] Figure 3 The attached figure is a cross-sectional view of the fiber optic collimator that utilizes inclined planes to achieve stable positioning according to this utility model.

[0029] Figure 4 The attached figure is a cross-sectional view of the fiber collimator of Embodiment 1 provided by this utility model;

[0030] Figure 5 The attached figure is a cross-sectional view of the fiber collimator of Embodiment 2 provided by this utility model;

[0031] Figure 6 The attached figure is a cross-sectional view of the fiber collimator of Embodiment 3 provided by this utility model;

[0032] Figure 7 The attached figure is a radial cross-sectional view of the fiber optic collimator provided by this utility model;

[0033] Figure 8 The attached figure is a cross-sectional view of the fiber collimator of Embodiment 4 provided by this utility model.

[0034] in:

[0035] 1-Collider body;

[0036] 11-Fiber optic access point;

[0037] 2-Adjusting cap;

[0038] 3-Adjusting spring;

[0039] 4-Lens holder;

[0040] 41-V-groove;

[0041] 5-Top ring;

[0042] 6-Sloping type mating structure;

[0043] 7- Locking component;

[0044] 71-Top screw. Detailed Implementation

[0045] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0046] The structure of a traditional fiber optic collimator is as follows: Figure 1 and Figure 2As shown, it includes: a collimator body 1, one end of which has an optical fiber inlet 11, and the other end of which is threadedly connected to an adjustment cap 2. The inner cavity of the collimator body 1 is provided with an adjustment spring 3, a lens support 4 and a top ring 5 that abut against each other in sequence from the optical fiber inlet 11 toward the adjustment cap 2. The lens support 4 is provided with a lens assembly. The position of the lens assembly can be adjusted by turning the adjustment cap 2.

[0047] When adjusting the focus, the lens holder moves the lens assembly back and forth, compressing or extending the adjusting spring 3. One end of the adjusting spring 3 presses against the collimator body 1, and the other end presses against the lens holder 4, adjusting the distance of the lens assembly relative to the optical fiber. Since the adjusting spring 3 is helical, if the direction of the spring force changes, there will be vertical components. When there is a gap in the track, the lens holder 4 will irregularly tilt or move to one side, causing optical path shifts and jumps (accidental jumps occur during the rotational movement of the focus, causing a large instantaneous change in spring force at the spring contact point). Furthermore, when the spring extends or retracts, its contact point in the xy direction will inevitably change due to friction causing sliding movement and the limitations of its helical structure. Therefore, when you want to restore a fixed original position after moving back and forth, a 100% perfect restoration is impossible because it cannot be guaranteed that the contact point will remain at a fixed point in the plane after one round trip. For a plane, there are no structural limitations, making this impossible. At the same time, the track gap is necessary; otherwise, the focusing function cannot be achieved. Therefore, the only solution is to optimize the structure near the contact surface.

[0048] See appendix Figure 3 This utility model discloses an optical fiber collimator that achieves stable positioning using inclined planes:

[0049] One or both ends of the lens holder 4 are set as inclined surfaces, so that the lens holder 4 and the adjusting spring 3 and / or the top ring 5 form a ramp-type mating structure 6. Through the inclined surface of the lens holder 4, the adjusting spring 3 or the top ring 5 at either end of the lens holder 4 forms an oblique force relative to the lens holder 4 that deviates from the axis of the collimator body 1, thereby causing an outer side wall of the lens holder 4 to be pressed against the inner side wall of the collimator body 1.

[0050] The collimator body 1 is provided with a locking component 7 for locking the lens holder 4. The locking component 7 is opposite to the contact position of the lens holder 4 and the collimator body 1.

[0051] Example 1:

[0052] See appendix Figure 4In this embodiment, the side of the lens holder 4 facing the adjusting spring 3 is inclined, forming a ramp-type mating structure 6 between the lens holder 4 and the adjusting spring 3. Because it is inclined, the elastic force of the adjusting spring 3 is always inclined downwards, and the lens holder 4 is always in contact with the side wall of the collimator body 1. Simply put, when stationary, the lens holder 4 and the top ring 5 will always be attached to the lower part of the inner wall of the collimator body 1, which ensures that the axial component force is coaxial and avoids rotation.

[0053] In summary, this ensures that there will be no abrupt changes in the x and y directions when the lens holder 4 moves back and forth. Furthermore, when the locking component 7 is locked, the direction of the light does not change. The resultant force of the locking component 7 is in the same direction as the offset direction of the lens holder 4, thus restricting the position of the lens holder 4 and preventing abrupt changes when locked.

[0054] The inclination angle of the inclined plane is defined as θ, which is generally 3-25°. The radial component of the force will cause sliding friction on the contact surface between the lens support 4 and the collimator body 1. The larger the angle, the greater the friction. Therefore, the angle should not be too large, otherwise the spring force will not be able to push the lens support 4 to move, or the friction will be too large during use or when the focal length changes.

[0055] This method decouples the disturbance and avoids the abrupt changes during switching. It also prevents movement when locked, ensuring that the light spot direction remains unchanged in different adjustment states and when locked.

[0056] In this embodiment, the tilt angle of the inclined surface of the lens holder 4 is 5°.

[0057] To further optimize the above technical solution, the locking component 7 includes a set screw 71 that is threadedly connected to the side wall of the collimator body 1.

[0058] To further optimize the above technical solution, there are multiple set screws 71, which are arranged along the axial direction of the collimator body 1.

[0059] See appendix Figure 7 The outer side wall of the lens holder 4 is provided with a V-shaped groove 41 corresponding to the set screw 71.

[0060] In this embodiment, the set screw 71 is a wave screw.

[0061] The two sides of the top ball of the ball screw symmetrically abut against the two side walls of the V-groove 41.

[0062] In traditional collimators, during the locking process, due to the aforementioned instability factors, the direction of the resultant force on the lens support 4 when it is adjusted to the appropriate position is not the same as the direction of the elastic force of the locking clamp. Therefore, the beam direction changes during locking. This phenomenon needs to be eliminated and is undesirable during use; it is called the jump phenomenon. Therefore, one of the optimization points of this embodiment is to eliminate the jump phenomenon.

[0063] like Figure 7 As shown, by adding a V-groove 41 to the lens holder 4, a fixed and locked state is achieved, thus preventing jumps when locked. The small ball at the top of the ball screw contacts the V-groove 41, obtaining a resultant force in the y-direction. This resultant force can limit the left and right movement of the lens holder 4, maintaining directional stability during locking. During forward and backward displacement, the V-groove 41 can restrict the trajectory in the xy-direction, allowing the lens holder to move along the direction of the V-groove. In summary, this solution can also maintain stability during both adjustment and locking.

[0064] Example 2:

[0065] See appendix Figure 5 The difference between this embodiment and embodiment 1 is that in this embodiment, the side of the lens holder 4 facing the top ring 5 is inclined, so that the lens holder 4 and the top ring 5 form a slope-type mating structure 6.

[0066] When the end of the lens holder 4 facing the top ring 5 is inclined, the end face of the top ring 5 is an inclined surface that matches the slope of the lens holder 4.

[0067] Example 3:

[0068] See appendix Figure 6 In this embodiment, both ends of the lens holder 4 are set as bevels, so that the lens holder 4, the adjusting spring 3 and the top ring 5 form a ramp-type mating structure 6.

[0069] In this embodiment, the end face of the top ring 5 is an inclined surface that matches the slope of the inclined surface of the lens support 4.

[0070] In this embodiment, the oblique surfaces on both sides of the lens holder 4 are arranged symmetrically.

[0071] Example 4:

[0072] See appendix Figure 8 Based on the optimization of embodiment 3, the two inclined surfaces on both sides of the lens holder 4 can be further simplified. Both ends of the lens holder 4 can be beveled and curved. In this way, the adjusting spring 3 and the lens holder 4 will have two points tangent to the vertex of the curve, and the top ring 5 and the lens holder 4 will also have two vertices tangent to it. This reduces friction and prevents the lens holder 4 from being selected.

[0073] Example 5:

[0074] This embodiment conducts an experiment on the switching of set screw 71: the light source is 650nm, the collimating lens focal length is 11mm, the collimator connector is a PC connector, a collimating focal length is selected, the spot diameter is 1692×1697μm, the observation screen is 2m away from the collimator, and the coordinate position of the spot center on the display screen is recorded as (0, 0). For other manufacturers without optimized collimators, after locking set screw 71, the coordinate position changes to (-3342μm, 4510μm), a change of 2.8mrad, and the spot diameter is 1705×1690μm; while using the optimized collimator, the coordinate position changes to (-12μm, -130μm), a change of 0.065mrad, and the spot diameter is 1685*1690μm.

[0075] Through the above experiments, it can be clearly found that the optimized collimator has a lower probability and impact of jump phenomenon during the locking of set screw 71 compared to other manufacturers.

[0076] Example 5:

[0077] This embodiment conducts a reset experiment: the light source is 650nm, the collimating lens focal length is 11mm, the collimator connector is a PC connector, a collimating focal length is selected, the light spot diameter is 1692×1697μm, the observation screen is 2m away from the collimator, and the coordinate position of the center of the light spot on the display screen is recorded as (0,0); a mark is made on the adjustment cap 2, each lens is rotated 10 revolutions and then returned 10 revolutions, the mark is restored to the same position, and the restoration result is recorded respectively.

[0078] Other manufacturers did not optimize the collimator. After tightening the set screw 71, the coordinate position changed to (4369μm, 2690μm), a change of 2.56mrad, and the spot diameter was 1712×1725μm. However, with the optimized collimator, the coordinate position changed to (-163μm, 98μm), a change of 0.095mrad, and the spot diameter was 1703×1698μm.

[0079] Through the above experiments, it can be clearly seen that the optimized collimator is significantly better than collimators from other manufacturers in restoring the target state by moving back and forth.

[0080] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to the method section.

[0081] The above description of the disclosed embodiments enables those skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A fiber optic collimator that achieves stable positioning using inclined planes, comprising: A collimator body (1) has an optical fiber inlet (11) at one end and an adjusting cap (2) threaded to the other end. The inner cavity of the collimator body (1) contains an adjusting spring (3), a lens holder (4), and a top ring (5) arranged sequentially from the optical fiber inlet (11) towards the adjusting cap (2). A lens assembly is housed within the lens holder (4), and the position of the lens assembly can be adjusted by turning the adjusting cap (2). The collimator body (1) is characterized by: One or both ends of the lens holder (4) are set as inclined surfaces, so that the lens holder (4) and the adjusting spring (3) and / or the top ring (5) form a ramp-type mating structure (6). Through the inclined surface of the lens holder (4), the adjusting spring (3) or the top ring (5) at any end of the lens holder (4) forms an oblique force relative to the lens holder (4) that deviates from the axis of the collimator body (1), thereby causing an outer side wall of the lens holder (4) to be pressed against the inner side wall of the collimator body (1); The collimator body (1) is provided with a locking component (7) for locking the lens holder (4), and the locking component (7) is opposite to the contact position of the lens holder (4) and the collimator body (1).

2. The fiber optic collimator for stable positioning using inclined planes as described in claim 1, characterized in that, When the end of the lens holder (4) facing the top ring (5) is an inclined surface, the end face of the top ring (5) is an inclined surface that matches the slope of the lens holder (4).

3. The fiber optic collimator for stable positioning using inclined planes as described in claim 1, characterized in that, The tilt angle of the inclined surface of the lens holder (4) is 3-25°.

4. The fiber optic collimator for stable positioning using inclined planes as described in claim 1, characterized in that, The locking assembly (7) includes a set screw (71) that is threaded to the side wall of the collimator body (1).

5. The fiber optic collimator for stable positioning using inclined planes according to claim 4, characterized in that, The number of set screws (71) is multiple, and they are arranged along the axial direction of the collimator body (1).

6. The fiber optic collimator for stable positioning using inclined planes according to claim 5, characterized in that, The outer side wall of the lens holder (4) is provided with a V-shaped groove (41) corresponding to the set screw (71) in the axial direction.

7. A fiber optic collimator for stable positioning using inclined planes as described in claim 6, characterized in that, The set screw (71) is a wave screw.

8. The fiber optic collimator for stable positioning using inclined planes according to claim 7, characterized in that, The top sphere of the wave screw symmetrically abuts against the two side walls of the V-groove (41).

9. A fiber optic collimator for stable positioning using inclined planes according to any one of claims 1-8, characterized in that, When both ends of the lens holder (4) are provided with inclined surfaces, the inclined surfaces on both sides are arranged symmetrically.

10. A fiber optic collimator for stable positioning using inclined planes according to claim 1, characterized in that, The bevel of the lens holder (4) is concave inward to form an arc shape.

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