Multi-mode short-distance optical device

Abstract

The utility model relates to the technical field of optical devices, in particular to a multimode short-distance optical device, which comprises a circuit board, a light emitting element, a light receiving element, a cushion block, a thermoelectric refrigerating unit and an optical lens. The light emitting element and the light receiving element are both arranged on the cold face of the thermoelectric refrigerating unit, the light emitting element is a vertical cavity surface emitting laser, and the optical lens is arranged on the emergent light path of the light emitting element and the incident light path of the light receiving element. And the reflector is used for reflecting and focusing the emitted light of the light emitting element into the multimode optical fiber and reflecting and focusing the incident light of the multimode optical fiber into the light receiving element. According to the utility model, a flexible assembly form is provided, the temperature of the heating element can be effectively controlled, and the problems of low efficiency and low precision in the aging process are solved; in addition, by arranging the light paths on the same stable structure, stable support is provided for the light paths, and the stability of the light paths is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to optical device technical field, specifically, relate to a multimode short distance optical device. BACKGROUND

[0002] Data centers have become the engine of modern life, and the growing network information is transmitted and stored through data centers. Most of the internal connections in the data center are short distances, ranging from a few meters to a few hundred meters. In these short-distance high-speed data communications, multimode optical fibers and optical modules with vertical cavity surface emitting lasers (VCSEL) as the core device have been widely used. Compared with single-mode transmission schemes, multimode schemes use low-cost, low-power lasers to achieve fast and efficient coupling between optical fibers and lasers. Multimode optical fibers can achieve higher transmission rates or longer transmission distances than copper cables, and lower costs than single-mode optical fiber systems.

[0003] However, the existing multimode transmission scheme often faces the following problems: (1) Low efficiency and accuracy of aging test. The existing multimode transmission scheme is often fixed in assembly form, with the circuit board directly serving as the carrier of the optical transceiver element. During the aging test, the entire circuit board needs to be placed in a high-temperature oven for high-temperature power-on, which brings many inconveniences to the aging test. Aging test is crucial to ensure the reliability and stability of the device. The inflexible assembly form limits the efficiency and accuracy of the aging test, making it difficult to quickly adjust and carry out large-scale, multi-dimensional aging tests under different test requirements and conditions, thereby affecting the accurate control and optimization of optical device quality; (2) Lack of effective active temperature control means. Since the PCB is a structure of multiple layers of resin superimposed, the thermal conductivity of the resin is poor, and the effect on heat conduction in the vertical direction is small. When all high-power bare chips are placed densely on the circuit board, the upper surface of the chip cannot conduct heat from the upper surface due to the influence of the lens array and air gap, but only from the lower surface. During the operation of the optical device, a large amount of heat will be generated. If it cannot be effectively dissipated in time, the temperature of the optical device will rise, and the high temperature will not only affect the photoelectric conversion efficiency of the optoelectronic device, but also accelerate the aging and performance degradation of the device material, shorten the service life of the device, and reduce the reliability and stability of the entire optical system. Low temperature is also the same, and some high-speed chips may have insufficient bandwidth at low temperature; (3) The stability of the optical path cannot meet the requirements of high-precision, high-stability optical communication and optical sensing systems. The instability of the optical path structure may cause an increase in transmission loss of optical signals, signal distortion, and a decrease in coupling efficiency, thereby limiting key performance indicators such as transmission distance, data transmission rate, and measurement accuracy of the system. In complex environments and long-term operation, the optical path cannot always be in the best working state, greatly restricting the in-depth application and expansion of related optical technology in a wider field.

[0004] Therefore, there is an urgent need for a multi-mode short-distance optical device with flexible assembly form, optimized heat dissipation function and stable optical path structure to overcome the defects of the prior art and meet the needs of the development of modern optical technology. The utility model discloses contents

[0005] The utility model discloses a multi-mode short-distance optical device with flexible assembly form, optimized heat dissipation function and stable optical path structure, which can solve the defects in the background art and meet the needs of the development of modern optical technology.

[0006] The utility model discloses a multi-mode short-distance optical device, including circuit board, light emitting element, light receiving element, cushion block, thermoelectric refrigerator and optical lens, the cushion block sets up on the circuit board, the thermoelectric refrigerator is arranged at the top of cushion block, light emitting element and light receiving element are evenly arranged at the cold face of thermoelectric refrigerator, the light emitting element is vertical cavity surface emitting laser, the optical lens is arranged on the emergent light path of light emitting element and the incident light path of light receiving element, is used for the reflection and focusing of the emission light of light emitting element to multimode optical fiber and the reflection and focusing of the incident light of multimode optical fiber to light receiving element.

[0007] According to a preferred embodiment, the top of the cushion block is slotted to form a first recessed groove area, and the thermoelectric refrigerator is placed in the first recessed groove area.

[0008] According to a preferred embodiment, the thermoelectric refrigerator is fixed in the first recessed groove area by adhesion.

[0009] According to a preferred embodiment, it further comprises an optical interface formed by a plug core, the multimode optical fiber is fixed inside the plug core, and the optical interface is placed in the first recessed groove area.

[0010] According to a preferred embodiment, the top of the cushion block is slotted to form a first recessed groove area, and the thermoelectric refrigerator is placed in the first recessed groove area.

[0011] According to a preferred embodiment, the optical lens is a lens base provided with a first collimating lens, a first focusing lens, a second collimating lens and a second focusing lens, and the lens base is further provided with a reflection inclined surface.

[0012] The first collimating lens and the first focusing lens are arranged on the emergent light path of the light emitting element, the first collimating lens is used for collimating the emission light of the light emitting element into parallel light and emitting to the surface of the reflection inclined surface, and after reflection by the surface of the reflection inclined surface, the light is focused by the first focusing lens into the multimode optical fiber inside the optical interface.

[0013] The second collimating lens and the second focusing lens are arranged on the incident light path of the light receiving element, the second collimating lens is used for collimating the emitted light of the multi-mode optical fiber into parallel light and emitting to the surface of the reflection inclined plane, and the light is focused into the light receiving element through the second focusing lens after being reflected by the surface of the reflection inclined plane.

[0014] According to a preferred embodiment, the lens base is slotted to form a second groove region near one side of the multi-mode optical fiber, and the first focusing lens and the second collimating lens are arranged in the second groove region.

[0015] According to a preferred embodiment, a thermistor is further included, the thermistor is fixed on the cold surface of the thermoelectric refrigerator, and a signal output end of the thermistor is electrically connected with a signal input end of the thermoelectric refrigerator.

[0016] According to a preferred embodiment, a laser driver chip and a transimpedance amplifier chip are further included, a signal output end of the laser driver chip is connected with a signal input end of the light emitting element, a signal input end of the transimpedance amplifier chip is connected with a signal output end of the light receiving element, and the laser driver chip and the transimpedance amplifier chip are electrically connected with the circuit board through connecting lines.

[0017] According to a preferred embodiment, the cushion block, the laser driver chip and the transimpedance amplifier chip are all fixed on the circuit board in a bonding manner.

[0018] The technical scheme of the multi-mode short-distance optical device provided by the utility model has at least the following advantages and beneficial effects: (1) the thermoelectric refrigerator is arranged on the top of the cushion block, and the light emitting element and the light receiving element are arranged on the cold surface of the thermoelectric refrigerator, the flexible assembly form can effectively control the temperature of the heating element, and the problems of low efficiency and low precision in the aging process are solved; (2) the light emitting element and the light receiving element are arranged on the thermoelectric refrigerator, and the optical lens is arranged above the thermoelectric refrigerator, the light path is arranged on the same stable structure, the light path is stably supported, and the light path stability is improved. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 The overall structure of the multi-mode short-distance optical device provided by the utility model embodiment 1 is shown in the top view;

[0020] Figure 2 The top view of the cushion block arrangement provided by the utility model embodiment 1 is shown;

[0021] Figure 3 The cushion block structure schematic view provided by the utility model embodiment 1 is shown;

[0022] Figure 4 The schematic view of the light path structure provided by the utility model embodiment 3 is shown;

[0023] Reference signs: 1-circuit board, 2-transimpedance amplifier chip, 3-laser driver chip, 4-optical transmitting element, 5-optical receiving element, 6-optical lens, 601-first collimating lens, 602-first focusing lens, 603-reflecting inclined surface, 604-second groove area, 7-pad block, 8-first metal positioning sheet, 9-second metal positioning sheet, 10-positioning needle, 11-ferrule, 12-thermoelectric cooler, 13-thermistor. DETAILED DESCRIPTION

[0024] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the following will be combined with the drawings in the embodiments of the present application to make a clear and complete description of the technical solutions in the embodiments of the present application. Obviously, the described embodiments are some but not all of the embodiments of the present application. The components of the embodiments of the present application described and shown in the drawings herein can be arranged and designed in various different configurations.

[0025] Embodiment 1

[0026] Figure 1 The overall structure of the multi-mode short-distance optical device provided by the embodiments of the present application is shown in a top view. Referring to FIG. 1, the structure of the multi-mode short-distance optical device includes a circuit board 1, an optical transmitting element 4, an optical receiving element 5, a pad block 7, a thermoelectric cooler 12, and an optical lens 6. Figure 1

[0027] In the present embodiment, the pad block 7 is used as a carrier of the related heat generating elements and the thermoelectric cooler 12. Specifically, in one implementation of the present embodiment, the pad block 7 is arranged on the circuit board 1, the thermoelectric cooler 12 is arranged on the top of the pad block 7, and the optical transmitting element 4 and the optical receiving element 5 are both arranged on the cold surface of the thermoelectric cooler 12. The heat generated by the optical transmitting element 4 and the optical receiving element 5 during operation is absorbed by the cold surface of the thermoelectric cooler 12, thereby achieving active temperature control of the optical transmitting element 4 and the optical receiving element 5.

[0028] Further, a thermistor 13 is also included, which is fixed on the cold surface of the thermoelectric cooler 12, and the signal output end of the thermistor 13 is electrically connected with the signal input end of the thermoelectric cooler 12.

[0029] It should be noted that, by arranging the thermoelectric cooler 12 on the top of the pad block 7 and arranging the optical transmitting element 4 and the optical receiving element 5 on the cold surface of the thermoelectric cooler 12, the flexible assembly form can effectively control the temperature of the heat generating elements, and at the same time, solve the problems of low efficiency and precision during the aging process. In addition, the temperature feedback is performed with the thermistor 13, forming feedback control of the thermoelectric cooler 12, and precise temperature control can be achieved.​

[0030] Furthermore, the optical emitting element 4 is a vertical-cavity surface-emitting laser, and the optical lens 6 is arranged in the output optical path of the optical emitting element 4 and the incident optical path of the optical receiving element 5, for reflecting and focusing the emitted light of the optical emitting element 4 into the multimode fiber and reflecting and focusing the incident light of the multimode fiber into the optical receiving element 5. Furthermore, the optical device also includes an optical port, which is provided with a positioning pin 10 for matching the ferrule 11 and the external optical interface. A first metal positioning piece 8 is provided on the first side of the optical port, and a second metal positioning piece 9 is provided on the second side of the optical port for fixing the positioning pin 10.

[0031] Furthermore, it also includes a laser driver chip 3 and a transimpedance amplifier chip 2. The signal output terminal of the laser driver chip 3 is connected to the signal input terminal of the light emitting element 4, and the signal input terminal of the transimpedance amplifier chip 2 is connected to the signal output terminal of the light receiving element 5. Both the laser driver chip 3 and the transimpedance amplifier chip 2 are electrically connected to the circuit board 1 through connecting wires. The pad 7, the laser driver chip 3, and the transimpedance amplifier chip 2 are all fixed to the circuit board 1 by adhesive bonding.

[0032] It should be noted that in this embodiment, by arranging the light emitting element 4 and the light receiving element 5 on the thermoelectric cooler 12 and arranging the optical lens 6 above it, the optical path is provided with stable support by arranging the optical path on the same stable structure, thereby improving the stability of the optical path.

[0033] Example 2

[0034] This embodiment further explains the arrangement of the pad 7 based on the technical solution provided in Embodiment 1:

[0035] In this embodiment, see Figure 2 and Figure 3 As shown, the top of the pad 7 is slotted to form a first groove area, and the thermoelectric cooler 12 is placed in the first groove area. Specifically, in one embodiment of this invention, the thermoelectric cooler 12 is fixed in the first groove area by adhesive bonding. The optical device also includes an optical interface formed by a ferrule 11, the multimode optical fiber is fixed inside the ferrule 11, and the optical interface is also placed in the first groove area and located on one side of the thermoelectric cooler 12.

[0036] Furthermore, a stepped area is formed on the top of the pad 7 outside the first groove area. The thermoelectric cooler 12, the light emitting element 4, and the light receiving element 5 are all located below the stepped area. The optical lens 6 is fixed to the stepped area by adhesive bonding. An air gap may be left between the light emitting element 4, the light receiving element 5, and the optical lens 6. This will not be described in detail here.

[0037] It should be noted that the above layout method can further improve space utilization and is beneficial for subsequent packaging.

[0038] Example 3

[0039] This embodiment further explains the optical path structure based on the technical solution provided in Embodiment 1:

[0040] In this embodiment, see Figure 4 As shown, the optical lens 6 is a lens substrate comprising a first collimating lens 601, a first focusing lens 602, a second collimating lens, and a second focusing lens. The lens substrate also comprises a reflecting slope 603. The first collimating lens 601 and the first focusing lens 602 are disposed in the outgoing light path of the light emitting element 4. The first collimating lens 601 is used to collimate the emitted light of the light emitting element 4 into parallel light and emit it onto the surface of the reflecting slope 603. After reflection by the surface of the reflecting slope 603, the light is focused by the first focusing lens 602 into the multimode optical fiber inside the optical interface. The second collimating lens and the second focusing lens are disposed in the incoming light path of the light receiving element 5. The second collimating lens is used to collimate the emitted light of the multimode optical fiber into parallel light and emit it onto the surface of the reflecting slope 603. After reflection by the surface of the reflecting slope 603, the light is focused by the second focusing lens into the light receiving element 5.

[0041] Furthermore, a second groove region 604 is formed by slotting the side of the lens substrate near the multimode fiber. The first focusing lens 602 and the second collimating lens are disposed in the second groove region 604, thereby reducing light loss and improving light efficiency.

[0042] Example 4

[0043] This embodiment is an alternative implementation of the optical path structure in Embodiment 3, specifically:

[0044] In this embodiment, the optical lens 6 and ferrule 11 are replaced with a 45° multimode fiber structure. The 45° multimode fiber structure means that a reflective surface is formed on the end face of the multimode fiber. After the light beam propagates from the multimode fiber, it changes direction at the end face of the multimode fiber and converges into the light receiving element 5. One end of the light emitting element 4 is reversed, so that the light beam propagates directly from the air to the end face of the multimode fiber, and then is reflected by the 45° surface and merges into the multimode fiber.

[0045] Example 5

[0046] This embodiment is an alternative implementation scheme for the transimpedance amplifier chip 2 and laser driver chip 3 layout in Embodiment 1, specifically as follows:

[0047] In the present embodiment, the transimpedance amplifier chip 2 and the laser driver chip 3 are arranged on the spacer 7, so that the customer obtains shorter connection line connections, which are more suitable for use in high-speed devices.

[0048] The above only is preferred embodiment of the present application, and is not used to limit the present application, for the person skilled in the art, the present application can have various changes and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A multimode short reach optical device, characterized in that, The application relates to a light emitting and receiving device, which comprises a circuit board (1), a light emitting element (4), a light receiving element (5), a cushion block (7), a thermoelectric refrigerator (12) and an optical lens (6), the cushion block (7) is arranged on the circuit board (1), the thermoelectric refrigerator (12) is arranged on the top of the cushion block (7), the light emitting element (4) and the light receiving element (5) are arranged on the cold surface of the thermoelectric refrigerator (12), the light emitting element (4) is a vertical cavity surface emitting laser, the optical lens (6) is arranged on the light emitting path of the light emitting element (4) and the light receiving path of the light receiving element (5), and is used for reflecting and focusing the emitted light of the light emitting element (4) into a multimode optical fiber and reflecting and focusing the incident light of the multimode optical fiber into the light receiving element (5).

2. The multimode short reach optical device of claim 1, wherein, The top of the cushion block (7) is slotted to form a first recessed groove area, and the thermoelectric refrigerator (12) is arranged in the first recessed groove area.

3. The multimode short reach optical device of claim 2, wherein, The thermoelectric refrigerator (12) is fixed in the first recessed groove area by adhesion.

4. The multimode short reach optical device of claim 2, wherein, The device further comprises a light interface formed by a plug (11), the multimode optical fiber is fixed in the plug (11), and the light interface is arranged in the first recessed groove area.

5. The multimode short reach optical device of claim 2, wherein, The top of the cushion block (7) is formed with a stepped area outside the first recessed groove area, and the optical lens (6) is fixed on the stepped area by adhesion.

6. The multimode short reach optical device of claim 5, wherein, The optical lens (6) is a lens base provided with a first collimating lens (601), a first focusing lens (602), a second collimating lens and a second focusing lens, and is further provided with a reflection inclined surface (603). The first collimating lens (601) and the first focusing lens (602) are arranged on the light emitting path of the light emitting element (4), the first collimating lens (601) is used for collimating the emitted light of the light emitting element (4) into parallel light and emitting the parallel light to the surface of the reflection inclined surface (603), the emitted light is reflected by the surface of the reflection inclined surface (603) and then focused by the first focusing lens (602) into the multimode optical fiber in the light interface. The second collimating lens and the second focusing lens are arranged on the light receiving path of the light receiving element (5), the second collimating lens is used for collimating the emitted light of the multimode optical fiber into parallel light and emitting the parallel light to the surface of the reflection inclined surface (603), the emitted light is reflected by the surface of the reflection inclined surface (603) and then focused by the second focusing lens into the light receiving element (5).

7. The multimode short reach optical device of claim 6, wherein, The lens base is slotted on the side close to the multimode optical fiber to form a second recessed groove area (604), and the first focusing lens (602) and the second collimating lens are arranged in the second recessed groove area (604).

8. The multimode short reach optical device of claim 1, wherein, The device further comprises a thermistor (13), the thermistor (13) is fixed on the cold surface of the thermoelectric refrigerator (12), and the signal output end of the thermistor (13) is electrically connected with the signal input end of the thermoelectric refrigerator (12).

9. The multimode short reach optical device of claim 1, wherein, Also included are a laser driver chip (3) and a trans-impedance amplifier chip (2), a signal output end of the laser driver chip (3) is connected with a signal input end of the light emitting element (4), a signal input end of the trans-impedance amplifier chip (2) is connected with a signal output end of the light receiving element (5), and the laser driver chip (3) and the trans-impedance amplifier chip (2) are electrically connected with the circuit board (1) through connecting lines.

10. The multimode short reach optical device of claim 9, wherein, The cushion block (7), the laser driver chip (3) and the trans-impedance amplifier chip (2) are all fixed on the circuit board (1) by means of adhesion.

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