Multi-mode lens and multi-mode optical module

Abstract

The utility model relates to a multimode lens, which is characterized in that a first total reflection surface inclined by 45 degrees is arranged on a base body made of PE (Polyethylene) I plastic, an air cavity is arranged on the base body, the wall surface, close to the first total reflection surface, of the air cavity is a second total reflection surface inclined by 45 degrees, and the lower end of the air cavity is positioned in a parallel light path between the optical fiber side of the base body and the 45-degree total reflection surface; the air cavity is not filled with or filled with high-refractive-index glue with the refractive index larger than 1.17. According to the multi-mode optical module, a multi-mode lens is fixed on a PCB, a Vcse l chip and an MPD are arranged in the coverage area of the multi-mode lens on the PCB, the Vcse l chip is coupled with a first total reflection surface, the MPD is coupled with a second total reflection surface, and an optical fiber coupled with the first total reflection surface is arranged on the optical fiber side of the multi-mode lens. The multi-mode lens has the beneficial effects that the multi-mode lens can be applied to multi-mode optical modules with MPD and without MPD, and only one set of mold needs to be opened, so that the mold opening cost is reduced, and the unit price of the lens is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of optical modules, in particular to a multi-mode lens and a multi-mode optical module. Background Art

[0002] At present, lenses with backlight monitoring and lenses without backlight monitoring are two different lenses, so they are produced using two different sets of molds. Usually, one mold and one lens cannot be shared. The reason is: when the multi-mode optical module does not have an MPD (MPD is the detector for monitoring the backlight), since the MPD is not mounted, the light reflected from the original position of the MPD will be projected onto the PCB board. This light will usually be reflected in multiple paths onto the Vcse l chip, causing optical interference and affecting the optoelectronic performance. If two sets of molds are opened and two types of lenses are produced, it will be expensive. When the quantity of each lens decreases, the unit price of the lens will be high. Utility Model Content

[0003] The technical problem to be solved by the utility model is to provide a multi-mode lens and a multi-mode optical module to overcome the deficiencies in the above-mentioned prior art.

[0004] The utility model solves the above technical problems with the following technical solutions: a multimode lens, comprising: a substrate made of PEI plastic, the substrate having a first total reflection surface inclined at 45°, an air cavity being provided on the substrate between the optical fiber side thereof and the first total reflection surface, the wall surface of the air cavity close to the first total reflection surface being a second total reflection surface inclined at 45° and having a different inclination direction from the first total reflection surface, the lower end of the air cavity being in a parallel optical path between the optical fiber side of the substrate and the 45° total reflection surface; the air cavity is not filled or is filled with a high refractive index glue having a refractive index greater than 1.17.

[0005] The beneficial effects of the utility model are:

[0006] When the multi-mode optical module is equipped with MPD, the air cavity is not filled with high-refractive-index glue to destroy the total reflection condition, and the air cavity is filled with air. In the PEI plastic: si n45°×(1.6~1.65)=1.13~1.17, in the air: s in90°×1=1, and since 1.13~1.17>1, the second total reflection surface 131 can undergo total reflection. When the multi-mode lens is applied to the multi-mode optical module with MPD, when the light beam emitted by the Vcse l chip is reflected toward the optical fiber side through the first total reflection surface, since the lower end of the air cavity is in the parallel optical path between the base optical fiber side and the 45° total reflection surface, part of the light in the parallel optical path will undergo total reflection at the second total reflection surface and be reflected into the MPD by the second total reflection surface to achieve backlight monitoring.

[0007] For multimode optical modules without MPD, the air cavity is filled with high-refractive index glue with a refractive index greater than 1.17. In PEI plastic: si n45°×(1.6~1.65)=1.13~1.17, in high-refractive index glue 150: si n90°×n 胶水 =n 胶水 , n 胶水 is the refractive index of the high refractive index glue, since n 胶水 >1.17, so 1.13~1.17<n 胶水 At this time, the high refractive index glue 150 filled in the air cavity 130 destroys the total reflection condition of the second total reflection surface 131. When the multi-mode lens is used in a multi-mode optical module without MPD, when the light beam emitted by the Vcse l chip is reflected toward the optical fiber side through the first total reflection surface, the light in the parallel light path will transmit through the high refractive index glue, and will not be totally reflected at the second total reflection surface, that is, the total reflection condition at the second total reflection surface is destroyed by the high refractive index glue, so the light will not be reflected by the second total reflection surface to the PCB board at the original position of the MPD, so that multipath reflection will not occur to affect the Vcse l chip;

[0008] By not filling the air cavity of the multi-mode lens with or filling it with high-refractive index glue that destroys the total reflection condition, the multi-mode lens can be applied to multi-mode optical modules with and without MPD, and only one set of molds is needed, thereby reducing mold opening costs and lowering the unit price of the lens.

[0009] On the basis of the above technical solution, the present invention can also be improved as follows.

[0010] Furthermore, the refractive index of the high refractive index glue is 1.4 to 1.6.

[0011] A further beneficial effect of the above method is that in order to leave enough margin and based on cost and availability, the refractive index of the high refractive index glue is preferably 1.4 to 1.6.

[0012] Furthermore, opaque carbon powder is added into the high refractive index glue.

[0013] A further beneficial effect of adopting the above method is that the attenuation amount can be adjusted by adjusting the carbon powder ratio, and the adjustment is flexible to adapt to Vcse l chips with different optical powers.

[0014] Furthermore, the depth of the lower end of the air cavity in the parallel light path is less than 50 um.

[0015] The further beneficial effects of adopting the above are: under normal circumstances, the spot diameter of the parallel light path is usually around 300um, and light less than 50um does not affect the optical power reaching the optical fiber when it is reflected into the MPD. In addition, since the multi-mode lens generally requires an attenuation plate or an attenuation film to be added so that the optical power reaching the optical fiber is within the required size, the multi-mode lens can adjust the attenuation by adjusting the depth value of the air cavity in the parallel light path, and the light with increased attenuation is reflected toward the MPD.

[0016] Furthermore, the substrate optical fiber side has a lens array coupled to the first total reflection surface, the substrate chip side has a lens array coupled to the first total reflection surface, and the substrate chip side has a lens array coupled to the second total reflection surface.

[0017] Based on the above technical scheme, the utility model also provides a multi-mode optical module, including a multi-mode lens, the air cavity of the multi-mode lens is not filled with high-refractive-index glue with a refractive index greater than 1.17, the multi-mode lens is fixed on a PCB board, and a Vcse l chip and an MPD are provided on the PCB board in the multi-mode lens coverage area, the Vcse l chip is coupled to the first total reflection surface, the MPD is coupled to the second total reflection surface, and an optical fiber coupled to the first total reflection surface is arranged on the optical fiber side of the multi-mode lens.

[0018] Based on the above technical scheme, the utility model also provides a multi-mode optical module, including a multi-mode lens, the air cavity of the multi-mode lens is filled with high-refractive index glue with a refractive index greater than 1.17, the multi-mode lens is fixed on a PCB board, a Vcse l chip is provided on the PCB board in the multi-mode lens coverage area, the Vcse l chip is coupled to the first total reflection surface, and an optical fiber coupled to the first total reflection surface is arranged on the optical fiber side of the multi-mode lens. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 The structure of the multi-mode lens in the utility model is not filled with high refractive index glue;

[0020] Figure 2 The structure of the multi-mode lens filled with high refractive index glue in the utility model;

[0021] Figure 3 This is a structural diagram of a multi-mode optical module with MPD in the utility model;

[0022] Figure 4 This is a structural diagram of a multi-mode optical module without MPD in the present invention.

[0023] In the accompanying drawings, the components represented by the reference numerals are listed as follows:

[0024] 1. Multimode lens, 110. Substrate, 120. First total reflection surface, 130. Air cavity, 131. Second total reflection surface, 140. Lens array, 150. High refractive index glue, 2. PCB board, 3. Vcse l chip, 4. MPD, 5. Optical fiber. DETAILED DESCRIPTION

[0025] The principles and features of the present invention are described below in conjunction with the accompanying drawings. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0026] Example 1

[0027] A multimode lens, comprising: a substrate 110 made of PE I plastic, wherein the refractive index of PE I plastic in the prior art is between 1.6 and 1.65, the substrate 110 is provided with a first total reflection surface 120 inclined at 45 degrees, an air cavity 130 is provided between the optical fiber side of the substrate 110 and the first total reflection surface 120, and a wall surface of the air cavity 130 close to the first total reflection surface 120 is a second total reflection surface 131 inclined at 45 degrees and in a different direction from the first total reflection surface 120;

[0028] The lower end of the air cavity 130 is in the parallel optical path between the optical fiber side of the substrate 110 and the 45° total reflection surface, and the air cavity 130 is not filled with the high refractive index glue 150 with a refractive index greater than 1.17, or the air cavity 130 is filled with the high refractive index glue 150 with a refractive index greater than 1.17;

[0029] like Figure 1 As shown, when the multi-mode optical module is provided with MPD, at this time, the air cavity 130 is not filled with the high refractive index glue 150 for destroying the total reflection condition, and the air cavity 130 is filled with air;

[0030] In PE I plastic: si n45°×(1.6~1.65)=1.13~1.17, in air: si n90°×1=1, since 1.13~1.17>1, the second total reflection surface 131 can be totally reflected, when the multimode lens 1 is applied to a multimode optical module with MPD, when the light beam emitted by the Vcse l chip 3 is reflected toward the optical fiber side through the first total reflection surface 120, since the lower end of the air cavity 130 is in the parallel optical path between the optical fiber side of the substrate 110 and the 45° total reflection surface, part of the light in the parallel optical path will be totally reflected at the second total reflection surface 131, and reflected by the second total reflection surface 131 into the MPD4, so as to realize backlight monitoring;

[0031] like Figure 2As shown, for a multimode optical module without MPD, at this time, the air cavity 130 is filled with a high refractive index glue 150 with a refractive index greater than 1.17, the PEI plastic: si n45°×(1.6~1.65)=1.13~1.17, the high refractive index glue 150: si n90°×n 胶水 =n 胶水 , n 胶水 is the refractive index of the high refractive index glue, since n 胶水 >1.17, so 1.13~1.17<n 胶水 At this time, the high refractive index glue 150 filled in the air cavity 130 destroys the total reflection condition of the second total reflection surface 131. When the multimode lens 1 is used in a multimode optical module without MPD, when the light beam emitted by the Vcse l chip 3 is reflected toward the optical fiber side through the first total reflection surface 120, the light in the parallel light path will transmit through the high refractive index glue 150, and will not be totally reflected at the second total reflection surface 131, that is, the total reflection condition at the second total reflection surface 131 is destroyed by the high refractive index glue 150, so the light will not be reflected by the second total reflection surface 131 to the PCB board 2 at the original position of the MPD4, so that multipath reflection will not occur to affect the Vcse l chip 3.

[0032] Example 2

[0033] like Figure 2 As shown, this embodiment is a further improvement on the basis of embodiment 1, and the details are as follows:

[0034] In order to leave enough margin in engineering, and based on cost and availability, the refractive index of the high refractive index glue 150 is preferably 1.4 to 1.6.

[0035] Example 3

[0036] like Figure 2 As shown, this embodiment is a further improvement on the basis of Embodiment 1 or 2, and the details are as follows:

[0037] The high refractive index glue 150 is mixed with opaque carbon powder (black carbon powder can absorb light). By adjusting the carbon powder ratio, the attenuation amount can be adjusted, and the adjustment is flexible to adapt to Vcse l chips with different optical powers.

[0038] Example 4

[0039] like Figure 1 , Figure 2 As shown, this embodiment is a further improvement on the basis of Embodiment 1, 2 or 3, and the details are as follows:

[0040] The depth of the lower end of the air cavity 130 in the parallel light path is less than 50um. Normally, the spot diameter of the parallel light path is usually around 300um, and light less than 50um does not affect the optical power reaching the optical fiber when reflected into the MPD. In addition, since the multi-mode lens generally requires an attenuation plate or an attenuation film to be added so that the optical power reaching the optical fiber is within the required size, the multi-mode lens can adjust the attenuation by adjusting the depth value of the air cavity in the parallel light path, and the light with increased attenuation is reflected toward the MPD.

[0041] Example 5

[0042] like Figure 1 , Figure 2 As shown, this embodiment is a further improvement on any one of Embodiments 1 to 4, and the details are as follows:

[0043] The optical fiber side of the substrate 110 has a lens array 140 coupled to the first total reflection surface 120 , the chip side of the substrate 110 has a lens array 140 coupled to the first total reflection surface 120 , and the chip side of the substrate 110 has a lens array 140 coupled to the second total reflection surface 131 .

[0044] Example 6

[0045] like Figure 3 As shown, a multimode optical module comprises: a multimode lens 1 as described in any one of embodiments 1 to 5, the air cavity 130 of the multimode lens 1 is not filled with a high refractive index glue 150 with a refractive index greater than 1.17, the multimode lens 1 is fixed on a PCB board 2, a Vcse l chip 3 and an MPD 4 are provided on the PCB board 2 in the coverage area of ​​the multimode lens 1, the Vcse l chip 3 is coupled to the first total reflection surface 120, the MPD 4 is coupled to the second total reflection surface 131, and an optical fiber 5 coupled to the first total reflection surface 120 is arranged on the optical fiber side of the multimode lens 1;

[0046] When the light beam emitted by the Vcse l chip 3 is reflected into the optical fiber 5 through the first total reflection surface 120, since the lower end of the air cavity 130 is in the parallel light path between the optical fiber side of the substrate 110 and the 45° total reflection surface, part of the light in the parallel light path will be totally reflected at the second total reflection surface 131 and reflected into the MPD 4 by the second total reflection surface 131 to achieve backlight monitoring.

[0047] Example 7

[0048] like Figure 4As shown, a multimode optical module comprises: a multimode lens 1 as described in any one of embodiments 1 to 5, an air cavity 130 of the multimode lens 1 is filled with a high-refractive-index glue 150 with a refractive index greater than 1.17, the multimode lens 1 is fixed on a PCB board 2, a Vcse l chip 3 is provided on the PCB board 2 in the coverage area of ​​the multimode lens 1, the Vcse l chip 3 is coupled to a first total reflection surface 120, and an optical fiber 5 coupled to the first total reflection surface 120 is arranged on the optical fiber side of the multimode lens 1;

[0049] When the light beam emitted by the Vcse l chip 3 is reflected into the optical fiber 5 through the first total reflection surface 120, the light in the parallel optical path will transmit through the high refractive index glue 150, and will not be totally reflected at the second total reflection surface 131, that is, the total reflection condition at the second total reflection surface 131 is destroyed by the high refractive index glue 150, so the light will not be reflected by the second total reflection surface 131 to the PCB board 2 at the original position of the MPD4, so that multipath reflection will not occur and affect the Vcse l chip 3.

[0050] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations of the present invention. Ordinary technicians in the field can change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A multimode lens, characterized in that: include: A substrate (110) is made of PE I plastic, the substrate (110) is provided with a first total reflection surface (120) inclined at 45 degrees, an air cavity (130) is provided on the substrate (110) between the optical fiber side thereof and the first total reflection surface (120), the wall surface of the air cavity (130) close to the first total reflection surface (120) is a second total reflection surface (131) inclined at 45 degrees and having a different inclination direction from the first total reflection surface (120), the lower end of the air cavity (130) is located in a parallel optical path between the optical fiber side of the substrate (110) and the 45-degree total reflection surface; the air cavity (130) is not filled or is filled with a high refractive index glue (150) having a refractive index greater than 1.

17.

2. A multimode lens according to claim 1, characterized in that: The refractive index of the high refractive index glue (150) is 1.4 to 1.

6.

3. A multimode lens according to claim 1 or 2, characterized in that: The high refractive index glue (150) is mixed with light-proof carbon powder.

4. The multimode lens according to claim 1, characterized in that: The depth of the lower end of the air cavity (130) in the parallel light path is less than 50 um.

5. The multimode lens according to claim 1, characterized in that: The optical fiber side of the substrate (110) has a lens array (140) coupled to a first total reflection surface (120), the chip side of the substrate (110) has a lens array (140) coupled to the first total reflection surface (120), and the chip side of the substrate (110) has a lens array (140) coupled to a second total reflection surface (131).

6. A multimode optical module, characterized in that: The invention comprises a multimode lens (1) as claimed in claim 1, 4 or 5, wherein the air cavity (130) of the multimode lens (1) is not filled with a high refractive index glue (150) having a refractive index greater than 1.17, the multimode lens (1) is fixed on a PCB board (2), a Vcsel chip (3) and an MPD (4) are provided on the PCB board (2) in the coverage area of ​​the multimode lens (1), the Vcsel chip (3) is coupled to a first total reflection surface (120), the MPD (4) is coupled to the second total reflection surface (131), and an optical fiber (5) coupled to the first total reflection surface (120) is arranged on the optical fiber side of the multimode lens (1).

7. A multimode optical module, characterized in that: The invention comprises a multimode lens (1) as claimed in any one of claims 1 to 5, wherein the air cavity (130) of the multimode lens (1) is filled with a high-refractive-index glue (150) having a refractive index greater than 1.17, the multimode lens (1) is fixed on a PCB board (2), a Vcsel chip (3) is provided on the PCB board (2) in the area covered by the multimode lens (1), the Vcsel chip (3) is coupled to a first total reflection surface (120), and an optical fiber (5) coupled to the first total reflection surface (120) is arranged on the optical fiber side of the multimode lens (1).

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