A chipized integrated balanced probe

Abstract

The application discloses a kind of balanced detector of chip integration, including optical input module, optical processing chip, photoelectric conversion module and external circuit module.Wherein, two input optical fibers respectively input local oscillator light and signal light;The optical processing chip includes optical input port, 1: n (n≥1) 2×2 coupler and optical output port, optical input port is transmitted to 2×2 coupler with local oscillator light and signal light, 1: n end input light, wherein, 1 end input local oscillator light, n end input signal light, after being coupled, a group of differential optical signals with substantially consistent optical intensity and 180° phase difference are obtained, and are output to photoelectric conversion module through two optical output ports;Photoelectric conversion module realizes the electrical connection between optical detector chip and external circuit processing module.The application uses chipized optical coupler to realize the coherent mixing of local oscillator light and signal light, and gets rid of the use of optical fiber beam splitter, reduces the integration difficulty of coherent detection system.

Description

Technical Field

[0001] This invention relates to the field of balance detection, and more particularly to a chip-integrated balance detector. Background Technology

[0002] As a core component of coherent optical communication systems and frequency modulated continuous wave (FMCW) lidar, balanced detectors have advantages such as reducing DC components, increasing AC amplitude, and increasing dynamic range, playing a crucial role in long-distance detection, imaging, and optical communication applications.

[0003] Current balanced detectors require the use of fiber optic beam splitters to coherently mix the local oscillator light and the signal light into two optical signals with essentially the same intensity before connecting them to the optical input interface of the balanced detector. This makes it difficult to meet the requirements of application platforms and scenarios such as drones, autonomous vehicles, and data centers that have strict requirements for size and dimensions.

[0004] In addition, some solutions use direct fabrication of germanium-silicon detectors on optical chips, which results in a large dark current and limits the detection lower limit of the balanced detector module. Summary of the Invention

[0005] To address the above problems, this invention proposes a chip-integrated balanced detector.

[0006] To achieve the objectives of this invention, a chip-integrated balanced detector is provided, comprising: an optical input module, an optical processing chip, a photoelectric conversion module, and an external circuit module;

[0007] The optical input module includes: a first input optical fiber and a second input optical fiber;

[0008] The optical processing chip includes: a first optical input port, a second optical input port, a 1:n 2×2 coupler, a first optical output port, and a second optical output port;

[0009] The photoelectric conversion module includes: a first photodetector, a second photodetector, and an electrode adapter plate; the electrode adapter plate is a three-sided gold-plated electrode adapter plate; the electrode adapter plate includes: a first electrode, a second electrode, a third electrode, and a fourth electrode; the first electrode includes: a1 surface, b1 surface, and c1 surface; the second electrode includes: a2 surface, b2 surface, and c2 surface; the third electrode includes: a3 surface, b3 surface, and c3 surface; the fourth electrode includes: a4 surface, b4 surface, and c4 surface; the first photodetector includes: a first photosensitive surface; the second photodetector includes: a second photosensitive surface;

[0010] The external circuit module includes: a power supply circuit, several pads, several transimpedance amplifier circuits, a differential amplifier circuit, and an output signal interface;

[0011] The first input optical fiber is aligned with the first optical input port, and the second input optical fiber is aligned with the second optical input port; one end of the 1:n 2×2 coupler is connected to the first optical input port; the n end of the 1:n 2×2 coupler is connected to the second optical input port; one end of the first optical output port is connected to one output port of the 1:n 2×2 coupler, and the other end is aligned with the first photosensitive surface; one end of the second optical output port is connected to the other output port of the 1:n 2×2 coupler, and the other end is aligned with the second photosensitive surface.

[0012] The first photodetector is attached to surface a1 of the first electrode, and the first photosensitive surface faces away from surface a1 of the first electrode; the second photodetector is attached to surface a4 of the fourth electrode, and the second photosensitive surface faces away from surface a4 of the fourth electrode; the positive and negative electrodes of the first photodetector are electrically connected to surface a1 of the first electrode and surface a2 of the second electrode, respectively; the positive and negative electrodes of the second photodetector are electrically connected to surface a4 of the fourth electrode and surface a3 of the third electrode, respectively.

[0013] The b1 surface of the first electrode, the b2 surface of the second electrode, the b3 surface of the third electrode, and the b4 surface of the fourth electrode are electrically connected to a plurality of the pads one by one; the plurality of pads are connected in parallel in pairs and then connected in series with a transimpedance amplifier circuit, and then connected in series with the transimpedance amplifier circuit, the differential amplifier circuit, and the output signal interface in sequence; the plurality of pads, the plurality of transimpedance amplifier circuits, the differential amplifier circuit, and the output signal interface are interconnected through the power supply circuit.

[0014] Furthermore, the first input optical fiber and the second input optical fiber are inclined optical fibers, planar optical fibers, or tapered lens optical fibers; the optical input module further includes: a first optical fiber fixing component and a second optical fiber fixing component; the first optical fiber fixing component is used to fix the first input optical fiber; the second optical fiber fixing component is used to fix the second input optical fiber;

[0015] Furthermore, the first and second fiber fixing components are made of loose tubes, fixing blocks, or metal tubes.

[0016] Furthermore, the first optical input port and the second optical input port adopt grating couplers or end-face couplers; the first optical output port and the second optical output port adopt end-face couplers.

[0017] Furthermore, the first photodetector and the second photodetector are either two independent photodetectors or a set of detector arrays.

[0018] Furthermore, the first photodetector is connected to the a1 surface of the first electrode by metal bonding or adhesive bonding; the second photodetector is connected to the a4 surface of the fourth electrode by metal bonding or adhesive bonding.

[0019] Furthermore, the bottom of the first photodetector is flush with the bottom of the a1 surface of the first electrode; the bottom of the second photodetector is flush with the bottom of the a4 surface of the fourth electrode; the width s1 of the first photodetector is equal to the width L1 of the first electrode; the width s2 of the second photodetector is equal to the width L2 of the fourth electrode; the center distance d1 from the first photosensitive surface to the second photosensitive surface is equal to the center distance d2 from the a1 surface of the first electrode to the a4 surface of the fourth electrode.

[0020] Furthermore, metal wires are welded to the c1 surface of the first electrode, the c2 surface of the second electrode, the c3 surface of the third electrode, and the c4 surface of the fourth electrode.

[0021] Furthermore, the positive and negative electrodes of the first photodetector are connected to the a1 surface of the first electrode and the a2 surface of the second electrode, respectively, by gold wire bonding or conductive adhesive bonding; the positive and negative electrodes of the second photodetector are connected to the a4 surface of the fourth electrode and the a3 surface of the third electrode, respectively, by gold wire bonding or conductive adhesive bonding.

[0022] Furthermore, the external circuit module adopts a circuit PCB board, a SIP integrated module, or a CMOS integrated circuit, and the optical input module, optical processing chip, photoelectric conversion module, and external circuit module are integrated and packaged in the same housing using SIP technology.

[0023] Compared with the prior art, the present invention has the following beneficial technical effects:

[0024] 1. This invention uses a chip-based optical coupler to achieve coherent mixing of local oscillator light and signal light, eliminating the need for fiber optic beam splitters and reducing the integration difficulty of coherent detection systems; and by using a 1:n 2×2 coupler, the signal light can be utilized to the maximum extent.

[0025] 2. This invention adopts a side-mounted method for the detector. By designing the electrodes on the electrode adapter board, the horizontal and vertical planes of the detector and the optical processing chip are aligned, thereby achieving high-efficiency coupling and reducing packaging difficulty. On this basis, this invention uses three-sided electrodes to monitor the photocurrent in real time, thereby maximizing the coupling efficiency between the detector and the optical chip.

[0026] 3. The detector chip used in this invention can be screened based on dark current and responsivity characteristics before packaging, thereby ensuring the stable performance of the balanced detector module.

[0027] 4. The balanced detector module of the present invention can be integrated in the same housing using SIP technology, which has a high degree of integration. At the same time, the optical fiber, optical processing chip, detector and external circuit are integrated in stages, and each part can be easily replaced. Attached Figure Description

[0028] Figure 1 This is a three-dimensional schematic diagram of the structure of a chip-integrated balanced detector according to one embodiment;

[0029] Figure 2 This is a schematic diagram of a chip-integrated balance detector module according to one embodiment;

[0030] Figure 3 This is a schematic cross-sectional view of a chip-integrated balanced detector according to one embodiment.

[0031] Figure 4 This is a three-dimensional structural diagram of an embodiment of a light processing chip;

[0032] Figure 5 This is a three-dimensional structural diagram of a photoelectric conversion module according to one embodiment;

[0033] Figure 6 A side view of a photoelectric conversion module according to one embodiment;

[0034] Figure 7 This is a structural diagram of a three-sided electrode adapter plate for a photoelectric conversion module according to one embodiment;

[0035] Figure 8 This is a schematic diagram of the external circuit module in one embodiment.

[0036] Reference numerals: 1-Optical input module, 2-Optical processing chip, 3-Photoelectric conversion module, 4-External circuit module, 1011-First input fiber, 1012-Second input fiber, 1021-First fiber fixing assembly, 1022-Second fiber fixing assembly, 2011-First optical input port, 2012-Second optical input port, 202-1:n 2×2 coupler, 2031-First optical output port, 2032-Second optical output port, 3011-First photodetector, 3012-Second photodetector, 302-Electrode adapter plate, 3031-First electrode, 3032-Second electrode, 3033-Third electrode, 3034-Fourth electrode, 3051-First photosensitive surface, 3052-Second photosensitive surface, 401-Power supply circuit, 402-Pad, 403-Transimpedance amplifier circuit, 404-Differential amplifier circuit, 405-Output signal interface. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0038] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0039] refer to Figure 1 , Figure 2 , Figure 3 As shown, a chip-integrated balanced detector includes: an optical input module 1, an optical processing chip 2, a photoelectric conversion module 3, and an external circuit module 4.

[0040] The optical input module 1 includes: a first input optical fiber 1011 and a second input optical fiber 1012;

[0041] like Figure 4 As shown, the optical processing chip 2 includes: a first optical input port 2011, a second optical input port 2012, a 1:n 2×2 coupler 202, a first optical output port 2031, and a second optical output port 2032;

[0042] like Figure 5 , Figure 6 , Figure 7 As shown, the photoelectric conversion module 3 includes: a first photodetector 3011, a second photodetector 3012, and an electrode adapter plate 302; the electrode adapter plate 302 is a three-sided gold-plated electrode adapter plate; the electrode adapter plate 302 includes: a first electrode 3031, a second electrode 3032, a third electrode 3033, and a fourth electrode 3034; the first electrode 3031 includes: a1 surface, b1 surface, and c1 surface; the second electrode 3032 includes: a2 surface, b2 surface, and c2 surface; the third electrode 3033 includes: a3 surface, b3 surface, and c3 surface; the fourth electrode 3034 includes: a4 surface, b4 surface, and c4 surface; the first photodetector 3011 includes: a first photosensitive surface 3051; the second photodetector 3012 includes: a second photosensitive surface 3052;

[0043] like Figure 8As shown, the external circuit module 4 includes: a power supply circuit 401, several pads 402, several transimpedance amplifier circuits 403, a differential amplifier circuit 404, and an output signal interface 405. Several pads 402 are reserved in the external circuit module 4 for electrical connection with the electrode adapter plate 302. These pads can be soldered to the tube shell pins, or they can be gold wire bonding or metal bonding. At the same time, the power supply circuit 401 supplies power to the entire external circuit module 4, the first photodetector (3011), and the second photodetector (3012). The electrical signal from the electrode adapter plate 302 is output as a radio frequency signal through the transimpedance amplifier circuit 403 and the differential amplifier circuit 404, and then output through the output signal interface 405.

[0044] The first input optical fiber 1011 is aligned with the first optical input port 2011, and the second input optical fiber 1012 is aligned with the second optical input port 2012; one end of the 1:n 2×2 coupler 202 is connected to the first optical input port 2011; the n end of the 1:n 2×2 coupler 202 is connected to the second optical input port 2012; one end of the first optical output port 2031 is connected to one output port of the 1:n 2×2 coupler 202, and the other end is aligned with the first photosensitive surface 3051; one end of the second optical output port 2032 is connected to the other output port of the 1:n 2×2 coupler 202, and the other end is aligned with the second photosensitive surface 3052.

[0045] The first photodetector 3011 is attached to the a1 surface of the first electrode 3031, and the first photosensitive surface 3051 faces away from the a1 surface of the first electrode 3031; the second photodetector 3012 is attached to the a4 surface of the fourth electrode 3034, and the second photosensitive surface 3052 faces away from the a4 surface of the fourth electrode 3034; the positive and negative electrodes of the first photodetector 3011 are electrically connected to the a1 surface of the first electrode 3031 and the a2 surface of the second electrode 3032, respectively; the positive and negative electrodes of the second photodetector 3012 are electrically connected to the a4 surface of the fourth electrode 3034 and the a3 surface of the third electrode 3033, respectively.

[0046] The b1 surface of the first electrode 3031, the b2 surface of the second electrode 3032, the b3 surface of the third electrode 3033, and the b4 surface of the fourth electrode 3034 are electrically connected to a plurality of pads 402 one by one; the plurality of pads 402 are connected in parallel in pairs and then connected in series with a transimpedance amplifier circuit 403, and then connected in series with the transimpedance amplifier circuit 403, the differential amplifier circuit 404, and the output signal interface 405 in sequence; the plurality of pads 402, the plurality of transimpedance amplifier circuits 403, the differential amplifier circuit 404, and the output signal interface 405 are interconnected through the power supply circuit 401.

[0047] The first optical input port 2011 and the second optical input port 2012 transmit the local oscillator light and the signal light to a 1:n 2×2 coupler 202, where the 1:n input ends are for the local oscillator light and the n input ends are for the signal light. After coherent mixing by the coupler, a set of differential optical signals with basically the same light intensity and a phase difference of 180° are obtained. These signals are then output to the first photodetector 3011 and the second photodetector 3012 through the first optical output port 2031 and the second optical output port 2032, respectively. After being guided and converted by the first electrode 3031, the second electrode 3032, the third electrode 3033 and the fourth electrode 3034, the current is guided from the vertical surfaces a1, a2, a3 and a4 to the horizontal surfaces b1, b2, b3 and b4, or to the other vertical surface c1, c2, c3 and c4.

[0048] In one embodiment, the first input optical fiber 1011 and the second input optical fiber 1012 are inclined optical fibers, planar optical fibers, or tapered lens optical fibers, used to match the light spot mode field of the first optical output port 2031 and the second optical output port 2032 in the optical processing chip 2; the optical input module 1 further includes: a first optical fiber fixing component 1021 and a second optical fiber fixing component 1022; the first optical fiber fixing component 1021 is used to fix the first input optical fiber 1011; the second optical fiber fixing component 1022 is used to fix the second input optical fiber 1012.

[0049] In one embodiment, the first optical fiber fixing assembly 1021 and the second optical fiber fixing assembly 1022 are loose tubes, fixing blocks, or metal tubes.

[0050] In one embodiment, the first optical input port 2011 and the second optical input port 2012 are grating couplers or end-face couplers; the first optical output port 2031 and the second optical output port 2032 are end-face couplers.

[0051] In one embodiment, the first photodetector 3011 and the second photodetector 3012 are two independent photodetectors, or a set of detector lines.

[0052] In one embodiment, the first photodetector 3011 is connected to the a1 surface of the first electrode 3031 by metal bonding or adhesive bonding; the second photodetector 3012 is connected to the a4 surface of the fourth electrode 3034 by metal bonding or adhesive bonding.

[0053] In one embodiment, the bottom of the first photodetector 3011 is flush with the bottom of the a1 surface of the first electrode 3031; the bottom of the second photodetector 3012 is flush with the bottom of the a4 surface of the fourth electrode 3034, to ensure that after encapsulation, the center of the first photosensitive surface 3051 is at the same height as the first light output port 2031, and the center of the second photosensitive surface 3052 is at the same height as the second light output port 2032; the width s1 of the first photodetector 3011 is equal to the width L1 of the first electrode 3031; the width s2 of the second photodetector 3012 is equal to the width L2 of the fourth electrode 3034; the center distance d1 from the first photosensitive surface 3051 to the second photosensitive surface 3052 is equal to the center distance d2 from the a1 surface of the first electrode 3031 to the a4 surface of the fourth electrode 3034, to ensure that the first photosensitive surface 3051 is aligned with the first light output port 2031, and the second photosensitive surface 3052 is aligned with the second light output port 2032.

[0054] In one embodiment, such as Figure 6 As shown, the height h3 of the first photosensitive surface 3051 is equal to the distance h1 from the bottom of the a1 surface of the first electrode 3031 to the bottom of the electrode adapter plate 302 plus the distance h2 from the center of the first photosensitive surface 3051 to the bottom of the a1 surface of the first electrode 3031, and h3 is equal to the height of the first light output port 2031; similarly, the height h4 of the second photosensitive surface 3052 is equal to the distance h5 from the bottom of the a4 surface of the fourth electrode 3034 to the bottom of the electrode adapter plate 302 plus the distance h6 from the center of the second photosensitive surface 3052 to the bottom of the a4 surface of the fourth electrode 3034, and h6 is equal to the height of the second light output port 2032, so as to ensure that the first photosensitive surface 3051 is aligned with the first light output port 2031 and the second photosensitive surface 3052 is aligned with the second light output port 2032.

[0055] In one embodiment, the integrated first photodetector 2031, second photodetector 2032, and electrode adapter plate 302 are mounted on the same plane as the light processing chip 2. They can be directly attached under a microscope, or alignment marks can be made on the electrode adapter plate 302, the light processing chip 2, and the attached plane for passive assembly. Alternatively, when pursuing extremely high coupling efficiency, active assembly can be performed. A three-sided gold-plated electrode adapter plate is selected, including two vertical electrodes and one horizontal electrode. The detector is attached to one vertical surface, and a metal wire is soldered to the other vertical surface for real-time monitoring of photocurrent during active coupling.

[0056] In one embodiment, metal wires are welded to the c1 surface of the first electrode 3031, the c2 surface of the second electrode 3032, the c3 surface of the third electrode 3033, and the c4 surface of the fourth electrode 3034.

[0057] In one embodiment, the positive and negative electrodes of the first photodetector 3011 are connected to the a1 surface of the first electrode 3031 and the a2 surface of the second electrode 3032, respectively, by gold wire bonding or conductive adhesive bonding; the positive and negative electrodes of the second photodetector 3012 are connected to the a4 surface of the fourth electrode 3034 and the a3 surface of the third electrode 3033, respectively, by gold wire bonding or conductive adhesive bonding.

[0058] In one embodiment, the external circuit module 4 is a circuit PCB board, a SIP integrated module, or a CMOS integrated circuit; the optical input module 1, the optical processing chip 2, the photoelectric conversion module 3, and the external circuit module 4 are integrated and packaged in the same housing using SIP technology, resulting in high integration; in some embodiments, the optical input module 1, the optical processing chip 2, and the photoelectric conversion module 3 can be integrated into one module and then interconnected with the external circuit module 4 to achieve the replaceability of each component.

[0059] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0060] It should be noted that the terms "first," "second," and "third" used in the embodiments of this application are merely to distinguish similar objects and do not represent a specific order of objects. It is understood that "first," "second," and "third" can be interchanged in a specific order or sequence where permitted. It should be understood that the objects distinguished by "first," "second," and "third" can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in an order other than those illustrated or described herein.

[0061] The terms "comprising" and "having," and any variations thereof, in this application are intended to cover non-exclusive inclusion. For example, a process, method, apparatus, product, or device that includes a series of steps or modules is not limited to the steps or modules listed, but may optionally include steps or modules not listed, or may optionally include other steps or modules inherent to such processes, methods, products, or devices.

[0062] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A chip-integrated balanced detector, characterized in that, include: Optical input module (1), optical processing chip (2), photoelectric conversion module (3) and external circuit module (4); The optical input module (1) includes: a first input optical fiber (1011) and a second input optical fiber (1012); The optical processing chip (2) includes: a first optical input port (2011), a second optical input port (2012), a 1:n 2×2 coupler (202), a first optical output port (2031), and a second optical output port (2032); the photoelectric conversion module (3) includes: a first photodetector (3011) and a second photodetector (3012). Electrode adapter plate (302); the electrode adapter plate (302) is a three-sided gold-plated electrode adapter plate; the electrode adapter plate (302) includes: a first electrode (3031), a second electrode (3032), a third electrode (3033) and a fourth electrode (3034); the first electrode (3031) includes: a1 surface, b1 surface and c1 surface, the second electrode (3032) includes: a2 surface, b2 surface and c2 surface, the third electrode (3033) includes: a3 surface, b3 surface and c3 surface, the fourth electrode (3034) includes: a4 surface, b4 surface and c4 surface; the first photodetector (3011) includes: a first photosensitive surface (3051); the second photodetector (3012) includes: a second photosensitive surface (3052). The external circuit module (4) includes: a power supply circuit (401), several pads (402), several transimpedance amplifier circuits (403), a differential amplifier circuit (404), and an output signal interface (405). The first input optical fiber (1011) is aligned with the first optical input port (2011), and the second input optical fiber (1012) is aligned with the second optical input port (2012); one end of the 1:n 2×2 coupler (202) is connected to the first optical input port (2011); the n end of the 1:n 2×2 coupler (202) is connected to the second optical input port (2012); one end of the first optical output port (2031) is connected to one output port of the 1:n 2×2 coupler (202), and the other end is aligned with the first photosensitive surface (3051); one end of the second optical output port (2032) is connected to the other output port of the 1:n 2×2 coupler (202), and the other end is aligned with the second photosensitive surface (3052); The first photodetector (3011) is attached to the a1 surface of the first electrode (3031), and the first photosensitive surface (3051) is away from the a1 surface of the first electrode (3031); the second photodetector (3012) is attached to the a4 surface of the fourth electrode (3034), and the second photosensitive surface (3052) is away from the a4 surface of the fourth electrode (3034); the positive and negative electrodes of the first photodetector (3011) are electrically connected to the a1 surface of the first electrode (3031) and the a2 surface of the second electrode (3032), respectively; the positive and negative electrodes of the second photodetector (3012) are electrically connected to the a4 surface of the fourth electrode (3034) and the a3 surface of the third electrode (3033), respectively. The b1 surface of the first electrode (3031), the b2 surface of the second electrode (3032), the b3 surface of the third electrode (3033), and the b4 surface of the fourth electrode (3034) are electrically connected to a plurality of pads (402) one by one; the plurality of pads (402) are connected in parallel in pairs and then connected in series with a transimpedance amplifier circuit (403), and then connected in series with the transimpedance amplifier circuit (403), the differential amplifier circuit (404), and the output signal interface (405) in sequence; the plurality of pads (402), the plurality of transimpedance amplifier circuits (403), the differential amplifier circuit (404), and the output signal interface (405) are interconnected through the power supply circuit (401).

2. The chip-integrated balanced detector according to claim 1, characterized in that, The first input optical fiber (1011) and the second input optical fiber (1012) are inclined optical fibers, planar optical fibers, or tapered lens optical fibers; the optical input module (1) further includes: a first optical fiber fixing component (1021) and a second optical fiber fixing component (1022); the first optical fiber fixing component (1021) is used to fix the first input optical fiber (1011); the second optical fiber fixing component (1022) is used to fix the second input optical fiber (1012).

3. The chip-integrated balanced detector according to claim 2, characterized in that, The first optical fiber fixing assembly (1021) and the second optical fiber fixing assembly (1022) are made of loose tubes, fixing blocks or metal tubes.

4. The chip-integrated balanced detector according to claim 3, characterized in that, The first optical input port (2011) and the second optical input port (2012) are equipped with grating couplers or end-face couplers; the first optical output port (2031) and the second optical output port (2032) are equipped with end-face couplers.

5. A chip-integrated balanced detector according to claim 4, characterized in that, The first photodetector (3011) and the second photodetector (3012) are two independent photodetectors, or a set of detector lines.

6. The chip-integrated balanced detector according to claim 5, characterized in that, The first photodetector (3011) is connected to the a1 surface of the first electrode (3031) by metal bonding or adhesive bonding; the second photodetector (3012) is connected to the a4 surface of the fourth electrode (3034) by metal bonding or adhesive bonding.

7. A chip-integrated balanced detector according to claim 6, characterized in that, The bottom of the first photodetector (3011) is flush with the bottom of the a1 surface of the first electrode (3031); the bottom of the second photodetector (3012) is flush with the bottom of the a4 surface of the fourth electrode (3034); the width s1 of the first photodetector (3011) is equal to the width L1 of the first electrode (3031); the width s2 of the second photodetector (3012) is equal to the width L2 of the fourth electrode (3034); the center distance d1 between the first photosensitive surface (3051) and the second photosensitive surface (3052) is equal to the center distance d2 between the a1 surface of the first electrode (3031) and the a4 surface of the fourth electrode (3034).

8. A chip-integrated balanced detector according to claim 7, characterized in that, Metal wires are welded to the c1 surface of the first electrode (3031), the c2 surface of the second electrode (3032), the c3 surface of the third electrode (3033), and the c4 surface of the fourth electrode (3034).

9. A chip-integrated balanced detector according to claim 8, characterized in that, The positive and negative electrodes of the first photodetector (3011) are connected to the a1 surface of the first electrode (3031) and the a2 surface of the second electrode (3032) respectively by gold wire bonding or conductive adhesive bonding; the positive and negative electrodes of the second photodetector (3012) are connected to the a4 surface of the fourth electrode (3034) and the a3 surface of the third electrode (3033) respectively by gold wire bonding or conductive adhesive bonding.

10. A chip-integrated balanced detector according to claim 8, characterized in that, The external circuit module (4) adopts a circuit PCB board, a SIP integrated module, or a CMOS integrated circuit; the optical input module (1), the optical processing chip (2), the photoelectric conversion module (3), and the external circuit module (4) are integrated and packaged in the same housing using SIP technology.

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