Optical module
Technical Field
The utility model relates to an optical communication element makes technical field, especially relates to an optical module.
Background
With the rapid development of 5G communication and the increasing exuberance of the demand of cloud computing, the market demand for high-speed optical modules is increasing day by day. In response to the market demand for high bandwidth and high rate data transmission, module designs are increasingly being developed in the direction of miniaturization and high density. Chinese patent application CN 201710591780.5 proposes an optical module that separates the transmitter and receiver ends and places the laser array on a heat sink for heat dissipation. The optical system and the optical fiber connector are fixed together, and an optical assembly is arranged in the optical system. The entire optical system is then assembled with a heat sink. The laser and the photoelectric detector of the optical module are assembled on the basis of the heat sink when being assembled, and the optical module in the optical system is assembled on the basis of the optical system when being assembled. Finally, the optical system and the heat sink are assembled together, and the optical elements in the optical system are coupled to the laser and the photodetector. The difficulty of coupling the optical module increases and the assembly cost increases.
SUMMERY OF THE UTILITY MODEL
An object of the utility model is to provide an optical module, this optical module coupling is more convenient, and the assembly cost is lower.
To achieve one of the above objects, an embodiment of the present invention provides an optical module including a housing, a substrate, an optical assembly, an optical transmitter, an optical receiver, and a printed circuit board disposed in the housing, and an electronic component disposed on the printed circuit board,
the optical component and the light emitter are fixed on the substrate;
the substrate is made of metal, the substrate is in heat conduction connection with the shell, and heat generated by the light emitter is dissipated to the shell through the substrate;
light emitted by the light emitter is transmitted to the outside of the optical module after passing through the optical assembly, and light incident from the outside of the optical module is incident to the light receiver after passing through the optical assembly.
As an embodiment of the present application, a limiting portion for limiting at least some of the elements in the optical module is provided on the substrate.
As an embodiment of the present application, the optical transmitter includes a plurality of lasers, the optical receiver includes a plurality of photodetectors, and the optical component includes a wavelength division multiplexer, the wavelength division multiplexer performs a beam combining process on light emitted from the optical transmitter, and performs a beam splitting process on light transmitted to the photodetectors.
As an embodiment of the present application, the substrate includes an upper surface and a lower surface corresponding to the upper surface, the light emitter and the optical component corresponding to the light emitter are disposed on the upper surface of the substrate, and the light receiver and the optical component corresponding to the light receiver are disposed on the lower surface of the substrate.
As an embodiment of the present application, the substrate includes an upper surface and a lower surface corresponding to the upper surface; one part of the light emitter and the optical component corresponding to the light emitter is arranged on the upper surface of the substrate, and the other part of the light emitter and the optical component is arranged on the lower surface of the substrate; one part of the light receiver and the optical assembly corresponding to the light receiver is arranged on the lower surface of the substrate, and the other part of the light receiver and the optical assembly is arranged on the upper surface of the substrate.
In one embodiment of the present application, an optical fiber connector is disposed on the substrate, and the optical fiber connector is optically coupled to the wavelength division multiplexer.
As an embodiment of the present application, the circuit board is a hard circuit board, one end of the hard circuit board is fixed on the substrate, and the other end of the hard circuit board is provided with an electrical interface externally connected to the optical module.
As an embodiment of the present application, the optical receiver is fixed to the hard circuit board.
In one embodiment of the present application, the substrate is provided with alignment marks.
As an embodiment of the present application, the alignment mark is a through hole penetrating through the substrate.
Compared with the prior art, the beneficial effect of this application lies in: the optical component, the laser and the photoelectric detector can be assembled on the same reference, so that coupling of all elements is facilitated, and assembly cost is reduced.
Drawings
Fig. 1 is a schematic structural diagram of an optical module in embodiment 1 of the present application;
FIG. 2 is an exploded view of the light module shown in FIG. 1;
fig. 3 is a schematic structural view of the optical module shown in fig. 2 with a housing removed;
FIG. 4 is a schematic structural diagram of another view angle of the optical module shown in FIG. 3;
fig. 5 is a schematic structural diagram of an optical module of embodiment 2;
fig. 6 is a schematic structural view of the optical module shown in fig. 5 with a housing removed;
FIG. 7 is a schematic structural diagram of another view angle of the optical module shown in FIG. 6;
fig. 8 is a schematic view of the internal structure of the optical module according to embodiment 3.
Detailed Description
The present application will now be described in detail with reference to specific embodiments thereof as illustrated in the accompanying drawings. These embodiments are not intended to limit the present application, and structural, methodological, or functional changes made by those skilled in the art according to these embodiments are included in the scope of the present application.
In the various illustrations of the present application, certain dimensions of structures or portions may be exaggerated relative to other structures or portions for ease of illustration and, thus, are provided to illustrate only the basic structure of the subject matter of the present application.
Also, terms used herein such as "upper," "above," "lower," "below," and the like, denote relative spatial positions of one element or feature with respect to another element or feature as illustrated in the figures for ease of description. The spatially relative positional terms may be intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "below" or "beneath" other elements or features would then be oriented "above" the other elements or features. Thus, the exemplary term "below" can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.
Moreover, it will be understood that, although the terms first, second, etc. may be used herein to describe various elements or structures, these described elements should not be limited by the above terms. The above terms are only used to distinguish these descriptive objects from each other. For example, a first surface may be referred to as a second surface, and likewise, a second surface may also be referred to as a first surface, without departing from the scope of the application.
The application provides an optical module. The optical module is used for transmitting and receiving optical signals. The packaging mode can be QSFP packaging, OSFP packaging, SFP packaging and the like, and can be used for data centers or telecommunication markets. The optical module comprises a shell, a substrate arranged in the shell, an optical component, an optical transmitter, an optical receiver, a printed circuit board and an electronic element arranged on the printed circuit board. The optical component, the light emitter and the light receiver are fixed on the substrate; the substrate is made of metal, the substrate is in heat conduction connection with the shell, and heat generated by the light emitter is dissipated to the shell through the substrate; light emitted by the light emitter is transmitted to the outside of the optical module after passing through the optical assembly, and light incident from the outside of the optical module is incident to the light receiver after passing through the optical assembly. The optical assembly, the laser and the photoelectric detector of the optical module can be assembled by taking the reference substrate as the same reference, and the optical module has the advantages of convenience in coupling and low assembly cost. The optical module of the present application will be specifically described below with reference to two embodiments.
Example 1
Referring to fig. 1, the optical module 100 of this embodiment includes a housing 110 and a pull ring 112. The case 110 is composed of an upper case and a lower case. A pull ring 112 is fixed to the housing 110. At the left and right ends of the housing 110 are an optical interface 114 and an electrical interface 116, respectively.
Referring to fig. 2, the upper and lower housings are fixed together by screws 118. A circuit board 120 is disposed in the housing 110, and the circuit board 120 is a rigid circuit board on which a plurality of electronic components 122 are disposed. The electronic components 122 may be capacitors, resistors, electronic chips, and the like. The circuit board 120 is provided with a gold finger 124 at an end thereof near the electrical interface 116, and the gold finger 124 is mainly used for electrically connecting with an external element (e.g., a switch) so as to exchange signals. The other end of the circuit board 120 opposite to the gold finger 124 is fixed with a substrate 130. A cover plate 136 is fixed to the base plate 130. The base plate 130 and the cover plate 136 form a box in which the optical components, the optical transmitter and the optical receiver are disposed. The box formed by the base plate 130 and the cover plate 136 may be a hermetic box or a non-hermetic box. When the substrate 130 and the circuit board 120 are fixed in the housing 110, the substrate 130 is thermally connected to the housing 110, and a thermal pad may be disposed between the substrate 130 and the housing 110 for better heat dissipation.
Where the substrate 130 is provided with an optical connector 134 near the optical interface 114. In this embodiment, the number of optical connectors is two, one of the optical connectors is used for transmitting optical signals, and the other is used for receiving optical signals. The substrate 130 is L-shaped, and the optical connector 134 is fixed to a sidewall of the L-shaped substrate 130.
Referring to fig. 3 and 4, in this embodiment, the circuit board 120 is partially fixed to the substrate 130. The substrate 130 is made of a metal material. The heat sink is made of kovar, and tungsten and copper can be embedded in the heat sink to enhance heat dissipation. The substrate 130 includes a bottom surface and three sidewalls. A fiber optic connector 134 is secured to one of the three side walls. The circuit board 120 is fixed on the substrate 130 at a position opposite to the optical fiber connector 134, and the circuit board 120 is adhesively fixed on the substrate 130. The substrate 130 is provided with an optical component, an alignment mark 132, a position limiting portion 138, a light emitter 150 and a light receiver 160.
The optical assembly includes, among other things, a wavelength division multiplexer 142, a coupling lens 144, and a refractive prism 146. The alignment mark 132 is a through hole penetrating the substrate 130, and in other embodiments, the comparison table may be a reticle drawn on the substrate, a protrusion or a groove on the substrate, or a component fixed on the substrate. The number and position of the position-limiting portions 138 can be designed as desired, and the presence thereof can facilitate the fixing of the optical components on the substrate 130. The optical transmitter 150 includes a plurality of lasers arranged in an array. The light receiver 160 includes a plurality of photodetectors arranged in an array. The laser, a coupling lens corresponding to the laser, a wavelength division multiplexer and the like form an optical transmission assembly; the photoelectric detector, a corresponding coupling lens, a wavelength division multiplexer and the like form an optical receiver assembly; the light emitting assembly and the light receiving assembly are formed in a side-by-side arrangement on the same surface of the substrate 130. In other embodiments, they may also be distributed in different planes of the substrate 130, forming a stacked arrangement. A ceramic block is placed under the laser and a heat sink can be placed under the ceramic block and then secured to the substrate 130. The heat generated by the laser can thus be dissipated through the substrate 130 to the housing 110 and further to the outside of the housing 110. In this embodiment, the photodetector is fixed to the circuit board 120, and the circuit board 120 is a hard board and fixed to the substrate 130, so that the photodetector is also mounted on the same reference as the laser, the optical component, and the like. Of course, in other embodiments, the photodetector may be fixed on the substrate 130.
The optical path of the optical module 100 will be briefly described below. The light emitted from the laser is collimated by the coupling lens 144, the light from the coupling lens 144 reaches the wavelength division multiplexer 142 (here, a transmitting end wavelength division multiplexer), and the light from the wavelength division multiplexer reaches the optical fiber connector 134 (here, a transmitting end optical fiber connector) after passing through the prism 146. The optical fiber connector 134 is house integrated with an isolator. Light entering the optical module from the optical fiber connector 134 (here, the receiving-end optical fiber connector) passes through the corresponding refraction prism and then reaches the wavelength division multiplexer 142 (here, the receiving-end wavelength division multiplexer), and light coming out of the wavelength division multiplexer 142 finally reaches the photodetector. It should be noted that some components in the transmitting optical path and the receiving optical path may be added, reduced, replaced, or shared. For example, the prism can be omitted or replaced by optical fiber according to actual needs.
Example 2
Referring to fig. 5, the embodiment provides an optical module 200. The light module 200 includes a housing 220 and a pull ring 212. The optical module 200 of this embodiment is similar in structure to the optical module 100 of embodiment 1. The difference is that the optical module 100 of embodiment 1 has two optical fiber connectors, the number of lasers is four, and the number of photodetectors is also four, which are arranged on the same surface of the substrate. The optical module 200 of this embodiment has four optical fiber connectors, the number of lasers being eight, and the number of photodetectors also being eight, which are arranged on the two opposite surfaces of the substrate. As will be described in detail below.
Referring to fig. 6 and 7, fig. 6 and 7 are schematic internal structural diagrams of the optical module with the housing 220 removed, and fig. 6 and 7 respectively show the internal structural diagrams of the optical module with different viewing angles. The substrate 230 of the optical module 200 includes an upper surface 231 and a lower surface 233. The upper surface 231 and the lower surface 233 of the substrate 230 are oppositely disposed. Referring to fig. 6, the circuit board 220 is partially fixed on the upper surface 231, and the circuit board 220 is provided with an electronic component 222. The upper surface 231 is further provided with an optical transmitter 250 composed of eight lasers, and eight coupling lenses 244, two wavelength division multiplexers 242, a prism 246 and two optical fiber connectors 234 corresponding to the lasers. The substrate 230 is provided with a position-limiting portion 238 and an alignment mark 232, the position-limiting portion 238 is used for limiting the position of the wavelength division multiplexer 242, and the alignment mark 232 is used for assembly based on the position. Eight lasers are fixed on the substrate 230 and located at the ends of the circuit board 220.
Referring to fig. 7, a through hole 235 is formed on the substrate 230 to expose the circuit board 220. The through hole 235 is rectangular, and the light receiver 260 is disposed on the circuit board 220 in the through hole 235. The optical receiver 260 includes 8 photodetectors. Two sets of wavelength division multiplexers 242, refractive prisms 246 and alignment marks 232 are provided on the lower surface of the substrate 230. Light from the other two of the fiber connectors 234 passes through the wavelength division multiplexer 242 and reaches the photodetector.
The optical module shares four groups of wavelength division multiplexers, four optical fiber connectors, a plurality of coupling lenses, a refraction prism, a photoelectric detector, a laser and the like. It will be understood by those skilled in the art that the number and type of the above elements may be modified as desired. For example, when the optical module is a single-fiber bidirectional optical module, the number of optical fiber connectors can be reduced by half, and a circulator and other elements are correspondingly added.
In addition, the number of the alignment marks 232 is two, and the through holes are formed, so that the same alignment marks can be conveniently used on the upper surface 231 and the lower surface 232 of the substrate 230, thereby unifying the alignment reference and improving the assembly precision and convenience. The light emitting element and the light receiving element of the present embodiment are disposed on the upper surface 231 and the lower surface 233 of the substrate 230, respectively, and in other embodiments, it is also possible that a part of the light emitting element and a part of the light receiving element are disposed on the upper surface 231 of the substrate 230 and another part of the light emitting element and another part of the light receiving element are disposed on the lower surface 233 of the substrate 230.
Example 3
Referring to fig. 8, the embodiment provides an optical module. The optical module of this embodiment is similar in structure to the optical module 100 of embodiment 1. The difference is that the optical module of embodiment 1 is different from the optical module of this embodiment in the element configuration for realizing the wavelength division multiplexing function. The wavelength division multiplexer in embodiment 1 implements a wavelength division multiplexing function by combining a filter and a mirror. In this embodiment, an AWG (Arrayed Waveguide grating) is used to implement the function of wavelength division multiplexing.
Specifically, the optical module of this embodiment includes a circuit board 320, and a substrate 330 fixed to one end of the circuit board 320, and an optical interface 314 is disposed on one end of the substrate 330 away from the circuit board 320. The substrate 330 is provided with an optical transmitter and a corresponding optical component to guide light emitted from the optical transmitter to the optical interface 114. The circuit board 320 is a rigid circuit board, and the circuit board 320 is provided with an optical receiver and an AWG, and an end of the AWG away from the optical receiver is coupled to the optical fiber 370. The other end of the fiber is connected to an optical interface 114. The optical signal incident from the optical interface 114 passes through the optical fiber 370 to reach the AWG, and then is transmitted to the optical receiver. The optical fibers are fixed on the substrate 330, the optical fibers can be arranged by surrounding the fixing block, the optical fibers are prevented from being damaged or causing poor signals, and the optical fiber length tolerance can be absorbed by coiling the optical fibers.
The transmitting end of the optical module of this embodiment has the same structure as that of embodiment 1. Of course, the transmitting end may also adopt the structure of AWG, or other suitable structure.
The optical component, the laser, the photoelectric detector, the circuit board and even the optical fiber connector are all fixed on the same substrate. In this way, the individual elements can be referenced to the same datum during assembly, without having to be referenced to a different datum prior to assembly. Thus, the coupling of the components is more convenient, and the assembly cost is lower.
It should be understood that although the present description refers to embodiments, not every embodiment contains only a single technical solution, and such description is for clarity only, and those skilled in the art should make the description as a whole, and the technical solutions in the embodiments can also be combined appropriately to form other embodiments understood by those skilled in the art.
The above list of details is only for the practical implementation of the present invention, and they are not intended to limit the scope of the present invention, and all equivalent implementations or modifications that do not depart from the technical spirit of the present invention should be included in the scope of the present invention.