Low-loss lens fiber array unit

Abstract

The utility model provides a low-loss lens optical fiber array unit, which comprises a substrate, a cover plate and an optical fiber, the optical fiber is arranged between the substrate and the cover plate, the front end of the substrate is provided with a total reflection surface and a lens, the optical fiber reflects light signals to the lens through the total reflection surface, the front end of the substrate is provided with a light-permeable convex part, and the convex part is provided with a lens. The total reflection surface is arranged on the first side of the lug boss; the optical fiber is arranged on the second side of the lug boss; optical fiber matching paste is filled between the end surface of the optical fiber and the surface of the lug boss; the utility model can reduce the energy loss of optical signals and improve the performance of an optical system.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of optical fiber array, concretely relates to a low loss lens optical fiber array unit. BACKGROUND

[0002] The lens optical fiber array unit is an optical fiber array assembly integrated with a lens structure, which is usually composed of multiple optical fibers arranged in a specific manner (such as linear or two-dimensional array) and has a micro-lens (such as a spherical lens, a micro-column lens, etc.) processed or integrated on the end face of the optical fiber. The core function of the lens optical fiber array unit is to regulate the light field through the lens to achieve efficient optical coupling, collimation, focusing or beam shaping, thereby improving the efficiency and stability of optical signal transmission.

[0003] In the existing lens optical fiber array, there is an air gap between the end of the bare fiber segment of the optical fiber and the plastic lens. On the one hand, due to the difference in refractive index between air and the optical fiber and the plastic substrate, a large Fresnel reflection occurs at the interface, resulting in energy loss of the optical signal. On the other hand, the connecting surface between the end of the bare fiber segment and the plastic substrate may have microscopic unevenness or defects, and the light will be scattered due to these unevenness and defects during transmission, causing the optical signal to scatter in different directions and resulting in energy loss. SUMMARY

[0004] The utility model aims at providing a low loss lens optical fiber array unit.

[0005] In order to achieve the above-mentioned purpose, the utility model provides a low loss lens optical fiber array unit, which comprises a substrate, a cover plate and an optical fiber. The optical fiber is arranged between the substrate and the cover plate. The front end of the substrate is provided with a total reflection surface and a lens. The optical fiber reflects the optical signal to the lens through the total reflection surface. The front end of the substrate is provided with a light-transmissive protruding part. The total reflection surface is arranged on the first side of the protruding part. The optical fiber is arranged on the second side of the protruding part. The end face of the optical fiber and the surface of the protruding part are filled with optical fiber matching paste.

[0006] As can be seen from the above-mentioned scheme, the optical fiber matching paste is filled between the end face of the optical fiber and the surface of the protruding part to avoid the existence of air gap between the end of the optical fiber and the protruding part, which is beneficial to reduce the Fresnel reflection caused by the air gap between the end face of the optical fiber and the protruding part, thereby reducing the energy loss of the optical signal and improving the performance of the optical system. In addition, the optical fiber matching paste can fill the possible unevenness or defects between the end face of the optical fiber and the surface of the protruding part, avoid the existence of air in the middle, make the transmission path of the optical signal smoother, reduce the occurrence of scattering, thereby reduce the scattering loss and ensure the quality of the optical signal.

[0007] A further design involves providing a stop surface and a ramp on the second side of the protrusion. The stop surface is positioned below the ramp, with its upper edge lower than the highest point of the optical fiber. The ramp extends upward from the upper edge of the stop surface.

[0008] As can be seen from the above scheme, with the above settings, the fiber optic matching paste can enter between the fiber end face and the stop surface along the inclined surface, ensuring that the entire end face of the fiber is located within the fiber optic matching paste.

[0009] A further approach is to wrap fiber matching paste around the ends of the fiber.

[0010] As can be seen from the above scheme, the above settings help to ensure that the fiber optic matching paste can wrap around the fiber end from all sides, and ensure that the end face of the fiber can be submerged in the fiber optic matching paste, thus avoiding dead corners.

[0011] A further embodiment is that the substrate has a groove on the second side of the protrusion, and the groove is located below the end of the optical fiber; a cover plate is located on the second side of the protrusion, and a receiving groove is formed between the cover plate and the second side surface of the protrusion, and the receiving groove is connected to the groove; both the groove and the receiving groove are filled with optical fiber matching paste.

[0012] As can be seen from the above scheme, the filling amount of fiber optic matching paste can be increased by setting it up in the above way, and dead filling corners can be avoided.

[0013] A further option is to also provide a curing adhesive inside the receiving groove, with the curing adhesive positioned above the fiber optic matching paste.

[0014] As can be seen from the above scheme, the above settings are beneficial for fixing the fiber optic matching paste and preventing it from loosening or falling off.

[0015] A further embodiment is that the substrate has a raised portion and a recessed portion. The raised portion is located between the recessed portion and the raised portion. A mounting groove is formed on the raised portion. The optical fiber is placed in the mounting groove and spans over the recessed portion. The optical fiber is fixed to the substrate and the cover plate through an adhesive layer. The adhesive layer extends partially into the recessed portion.

[0016] As can be seen from the above scheme, the above settings facilitate the fixation of the optical fiber by the adhesive layer from all sides, thereby improving the installation firmness and long-term stability of the optical fiber.

[0017] A further option is that the adhesive layer includes a hard adhesive layer and a soft adhesive layer, with the soft adhesive layer disposed on the outside of the hard adhesive layer.

[0018] As can be seen from the above scheme, the above settings are beneficial in two ways: firstly, they help to fix the position of the optical fiber, ensuring the precise positioning and long-term stability of the optical fiber; secondly, they help to alleviate the stress on the optical fiber, prevent the optical fiber from breaking, and thus improve the overall mechanical strength of the lens fiber array unit.

[0019] A further embodiment is that the optical fiber includes a bare fiber portion and a wrapping portion. The bare fiber portion is disposed between the substrate and the cover plate and extends rearward to above the recessed portion. The rigid adhesive layer is simultaneously connected to the bare fiber portion, the wrapping portion, the cover plate, and the recessed portion.

[0020] A further proposed solution is to use a transparent plastic material for the substrate, and to mold the substrate, protrusions, total reflection surface, and lens as a single unit. Attached Figure Description

[0021] Figure 1 This is a structural diagram of an embodiment of the present utility model.

[0022] Figure 2 This is an exploded view of an embodiment of the present invention.

[0023] Figure 3 This is a cross-sectional view of an embodiment of the present utility model.

[0024] Figure 4 yes Figure 3 Enlarged view of point A in the middle.

[0025] The present invention will be further described below with reference to the accompanying drawings and embodiments. Detailed Implementation

[0026] See Figures 1 to 4 This embodiment provides a low-loss lens fiber array unit, including a substrate 1, a cover plate 2 and an optical fiber 3. The optical fiber 3 is disposed between the substrate 1 and the cover plate 2. The front end of the substrate 1 is provided with a total reflection surface 11 and a lens 12. The optical fiber 3 reflects the light signal to the lens 12 through the total reflection surface 11.

[0027] The front end of the substrate 1 is provided with a light-transmitting protrusion 13, a total reflection surface 11 is provided on the first side of the protrusion 13, and a lens 12 is provided on the lower side of the front end of the substrate 1. A raised part 14 is provided in the middle of the substrate 1, and a "V"-shaped mounting groove 141 is provided on the raised part 14.

[0028] The optical fiber 3 includes a bare fiber portion 31 and a wrapping portion 32. The bare fiber portion 31 is disposed within the mounting groove 141 and on the second side of the protrusion 13. A fiber matching paste 4 with a low refractive index is filled between the end face of the bare fiber portion 31 and the second side surface of the protrusion 13. Preferably, the refractive index of the fiber matching paste 4 is close to the refractive index of the fiber core of the optical fiber 3. In this embodiment, the refractive index of the fiber matching paste 4 is 1.46@1310+ / -20nm. The fiber optic matching paste 4 can fill the air gap between the end face of the bare fiber portion 31 and the protrusion 13, preventing the optical signal from being refracted through the air medium and then entering the protrusion 13. On the one hand, since the refractive index of the fiber optic matching paste 4 is close to that of the fiber core of the fiber 3, the fiber optic matching paste 4, when filled between the end face of the bare fiber portion 31 and the protrusion 13, eliminates the air gap, allowing light to be transmitted more smoothly from the fiber 3 to the substrate 1, greatly reducing reflection loss and improving the transmission efficiency of the optical signal. On the other hand, the fiber optic matching paste 4 can fill any unevenness or defects that may exist on the surface of the end face of the bare fiber portion 31 and the protrusion 13, preventing the presence of air in the middle and improving the path of optical signal transmission. The optical path is smoother, reducing scattering and thus lowering scattering loss, ensuring the quality of the optical signal. Moreover, the fiber matching paste 4 optimizes the optical connection between the fiber 3 and the substrate 1, allowing light to be transmitted at a more ideal angle and in a more ideal manner, improving the coupling efficiency between the two. In addition, the fiber matching paste 4 can also form a protective film on the end face of the fiber 3 and the surface of the protrusion 13, preventing dust, moisture, chemicals and other contaminants from the external environment from coming into contact with them, avoiding these contaminants from causing corrosion, oxidation or other damage to the surface of the fiber 3 and the protrusion 13, thereby extending the service life of the fiber 3 and optical components, and ensuring the long-term stability of the system.

[0029] Furthermore, a stop surface 131 and a ramp 132 are provided on the second side of the protrusion 13. The stop surface 131 is located below the ramp 132, and the upper edge of the stop surface 131 is lower than the highest point of the optical fiber 3. The stop surface 131 can be adjacent to or abut against the end face of the bare fiber portion 31. The ramp 132 extends upward at an angle from the upper edge of the stop surface 131. Due to the provision of the ramp 132, the optical fiber matching paste 4 can slide along the ramp 132 into the gap between the end face of the bare fiber portion 31 and the ramp 132 and the stop surface 131.

[0030] To ensure that the end face of the bare fiber portion 31 and the surface of the protrusion 13 are filled with fiber matching paste 4, in this embodiment, it is preferable that the end of the fiber 3 is completely encased in fiber matching paste 4 to avoid dead corners in the end face of the bare fiber portion 31. Specifically:

[0031] The substrate 1 has a groove 15 on the second side of the protrusion 13. The groove 15 is disposed between the pad 14 and the protrusion 13. The groove 15 is disposed below the stop surface 131 and is recessed into the bottom of the mounting groove 141, so that the end of the bare fiber portion 31 can be mounted over the groove 15.

[0032] The cover plate 2 is disposed on the second side of the protrusion 13, and a receiving groove 16 is formed between the end of the cover plate 2 and the second side surface of the protrusion 13. The receiving groove 16 is connected to the groove 15.

[0033] When filling the fiber optic matching paste 4, the fiber optic matching paste 4 can be filled into the groove 15 and the receiving groove 16.

[0034] To prevent the fiber optic matching paste 4 from loosening, this embodiment also includes a curing adhesive 5 within the receiving groove 16, positioned above the fiber optic matching paste 4. After curing, the curing adhesive 5 forms a solid, thus fixing the fiber optic matching paste 4 in place. In this embodiment, the curing adhesive 5 can be commercially available 353ND adhesive.

[0035] A recessed portion 17 is provided at the rear end of the substrate 1. The recessed portion 17 is located at the end of the raised portion 14 facing away from the groove 15, and the bottom wall of the recessed portion 17 is lower than the bottom of the mounting groove 141. The bare fiber portion 31 is disposed in the mounting groove 141 and partially spans over the recessed portion 17. The optical fiber 3 is fixed to the substrate 1 and the cover plate 2 by an adhesive layer, which partially extends into the recessed portion 17 to fix the optical fiber 3 and the cover plate 2. Specifically:

[0036] The adhesive layer includes a hard adhesive layer 6 and a soft adhesive layer 7, with the soft adhesive layer 7 disposed on the outside of the hard adhesive layer 6.

[0037] The bare fiber portion 31 is disposed between the substrate 1 and the cover plate 2 and extends rearward to above the recessed portion 17, and the partial wrapping portion 32 is also disposed above the recessed portion 17. The rigid adhesive layer 6 is connected to the bare fiber portion 31, the wrapping portion 32, the cover plate 2, and the recessed portion 17. The soft adhesive layer 7 is connected to the rigid adhesive layer 6, the wrapping portion 32, and the recessed portion 17.

[0038] In this embodiment, the substrate 1 is made of transparent plastic material, and the substrate 1, the protrusion 13, the total reflection surface 11 and the lens 12 are integrally formed.

[0039] In summary, this invention fills the space between the fiber end face and the protrusion surface with fiber matching paste to prevent air gaps between the fiber end face and the protrusion. This reduces Fresnel reflection caused by air gaps, thereby reducing optical signal energy loss and improving the performance of the optical system. Furthermore, the fiber matching paste fills any unevenness or defects that may exist on the fiber end face and the protrusion surface, preventing air pockets and making the optical signal transmission path smoother. This reduces scattering, thereby lowering scattering loss and ensuring optical signal quality.

[0040] Finally, it should be emphasized that the above are only preferred embodiments of this utility model and are not intended to limit this utility model. For those skilled in the art, this utility model can have various changes and modifications. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A low-loss lens fiber array unit, comprising a substrate, a cover plate, and an optical fiber, wherein the optical fiber is disposed between the substrate and the cover plate, and a total internal reflection surface and a lens are disposed at the front end of the substrate, and the optical fiber reflects an optical signal to the lens through the total internal reflection surface, characterized in that: The front end of the substrate is provided with a light-transmitting protrusion, and the total reflection surface is disposed on the first side of the protrusion. The optical fiber is disposed on the second side of the protrusion, and the end face of the optical fiber and the surface of the protrusion are filled with optical fiber matching grease.

2. The low-loss lens fiber array unit according to claim 1, characterized in that: A stop surface and an inclined surface are provided on the second side of the protrusion. The stop surface is located below the inclined surface, and the upper edge of the stop surface is lower than the highest point of the optical fiber. The inclined surface extends upward from the upper edge of the stop surface.

3. The low-loss lens fiber array unit according to claim 1, characterized in that: The fiber optic matching paste is also wrapped around the end of the fiber.

4. The low-loss lens fiber array unit according to claim 3, characterized in that: The substrate has a groove on the second side of the protrusion, and the groove is located below the end of the optical fiber; The cover plate is disposed on the second side of the protrusion, and a receiving groove is formed between the cover plate and the second side surface of the protrusion, the receiving groove communicating with the groove. Both the groove and the receiving slot are filled with the optical fiber matching paste.

5. The low-loss lens fiber array unit according to claim 4, characterized in that: The receiving groove is also provided with curing adhesive, which is positioned above the optical fiber matching paste.

6. The low-loss lens fiber array unit according to any one of claims 1 to 5, characterized in that: The substrate is provided with a raised portion and a recessed portion. The raised portion is disposed between the recessed portion and the raised portion. A mounting groove is formed on the raised portion. The optical fiber is disposed in the mounting groove and spans above the recessed portion. The optical fiber is fixed to the substrate and the cover plate by an adhesive layer. The adhesive layer extends partially into the recessed portion.

7. The low-loss lens fiber array unit according to claim 6, characterized in that: The adhesive layer includes a hard adhesive layer and a soft adhesive layer, with the soft adhesive layer disposed on the outside of the hard adhesive layer.

8. The low-loss lens fiber array unit according to claim 7, characterized in that: The optical fiber includes a bare fiber portion and a wrapping portion. The bare fiber portion is disposed between the substrate and the cover plate and extends rearward to above the recessed portion. The rigid adhesive layer is connected to the bare fiber portion, the wrapping portion, the cover plate, and the recessed portion.

9. The low-loss lens fiber array unit according to any one of claims 1 to 5, characterized in that: The substrate is made of transparent plastic material, and the substrate, the protrusion, the total reflection surface and the lens are integrally formed.

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