WO2020253534A1

WO2020253534A1 - Miniaturized wavelength-division-multiplexing optical receiving assembly and assembly method therefor

Info

Publication number: WO2020253534A1
Application number: PCT/CN2020/094168
Authority: WO
Inventors: 贾旭; 郑熙; 罗良涛; 江演; 任策; 于光龙
Original assignee: 福州高意光学有限公司
Priority date: 2019-06-20
Filing date: 2020-06-03
Publication date: 2020-12-24
Also published as: CN112114401A

Abstract

Disclosed are a miniaturized wavelength-division-multiplexing optical receiving assembly and an assembly method therefor. The assembly comprises an optical fiber collimator (1) for inputting signal light; a wavelength division multiplexing subassembly (2) for demultiplexing the signal light input by the optical fiber collimator (1) into several beams of collimated light; a right-angle prism (3), one right-angle surface of which is opposite an output end of the wavelength division multiplexing subassembly (2) and is used for receiving the plurality of beams of collimated light after demultiplexing is performed by the wavelength division multiplexing subassembly (2), and the plurality of beams of collimated light are reflected by a slope of the right-angle prism and are then output from the other right-angle surface of the right-angle prism (3); a lens array (4) arranged on two right-angle surfaces or one right-angle surface of the right-angle prism (3); and an optical substrate (5) for fixedly mounting the optical fiber collimator (1), the wavelength division multiplexing subassembly and the right-angle prism (3) relative to one another. The assembly has the remarkable advantages of a small wavelength change coefficient as a function of temperature, a high passband bandwidth, a low insertion loss, low crosstalk, etc.

Description

Miniaturized wave decomposition multiplexing optical receiving component and assembly method thereof

Technical field

The invention relates to the field of optical communication technology and devices, in particular to a miniaturized wave decomposition multiplexing light receiving component and an assembly method thereof.

Background technique

Wavelength Division Multiplexing (WDM, Wavelength Division Multiplexing) combines two or more optical carrier signals of different wavelengths (carrying various information) at the transmitting end through a multiplexer (also known as multiplexer, MUX for short) The technology of transmitting together and coupled to the same optical fiber of the optical line; at the receiving end, the optical carriers of various wavelengths are separated by a demultiplexer (also called demultiplexer, or DEMUX for short), and then The optical receiver performs further processing to restore the original signal. This technology of simultaneously transmitting two or more optical signals of different wavelengths in the same optical fiber is called wavelength division multiplexing. Wavelength division multiplexing technology can realize the transmission of signals of multiple wavelengths by a single optical fiber, which will double the transmission capacity of the optical fiber. It has been widely used in the medium and long-distance transmission of optical communications and the interconnection of data centers.

In the optical transceiver (Transceiver), in order to achieve wavelength division multiplexing (MUX) and demultiplexing (DEMUX), the core optical components are MUX and DEMUX optical components, of which Z-BLOCK and AWG (Arrayed Waveguide Grating) are two The most commonly used and typical MUX/DEMUX sub-components. Compared with AWG, Z-BLOCK has the advantages of low insertion loss, wide spectral bandwidth, low channel crosstalk, and low temperature sensitivity. It is more widely used in high-speed QSFP and OSFP optical transceivers such as 40G, 100G, and 400G. In each optical transceiver, there is usually a pair of Z-BLOCKs, which are used for MUX and DEMUX respectively. The schematic diagram is shown in Figure 1.

The typical structure of Z-BLOCK is shown in Figure 2. It consists of a parallelogram glass plate with polished front and rear sides. The front side of the glass plate contains areas coated with anti-reflection and high-reflection coatings, and several areas on the back are respectively plated Multiple WDM (wavelength division multiplexing) filter films of different wavelengths or multiple filters coated with WDM filter films of different wavelengths, the number of filters or filters is usually 4 or 8 . A collimated beam containing multiple wavelengths is incident from the incident end at a designed angle, and after being transmitted and reflected by a series of filter films, the optical signals of different wavelengths are separated to realize DEMUX, and vice versa to realize MUX.

The main function of the WDM optical receiving component is to collimate and demultiplex the multi-wavelength WDM light accessed by the optical fiber, and then couple it to the PD with high efficiency. As the core device in the optical transceiver, taking the 4-channel wave division multiplexing optical receiving component as an example, the existing technical solutions include:

The prior art scheme 1: adopts the method of assembling each discrete component individually and sequentially to realize the wave decomposition multiplexing. Discrete components include fiber collimators, WDM filters, mirrors, coupling lenses, prisms, or beam splitters. Each component needs to be actively adjusted and aligned, which has low assembly efficiency, high cost, and difficulty in miniaturization.

Existing technical solution 2: Z-BLOCK is used as the DEMUX sub-component, and the incident end also uses fiber collimators, but after Z-BLOCK, 4 fiber collimators are used for reception, or 4 separate lenses are used for coupling, This method also requires active adjustment of alignment, which has low assembly efficiency and high cost, and cannot be miniaturized.

Existing technical solution 3: AWG is used as the DEMUX sub-assembly, and the optical fiber head is directly coupled to the AWG input end waveguide for assembly, and the output end of the AWG is directly coupled to the PD array. Although this assembly method has the advantages of simplicity, efficiency and low cost, it can only be used in certain scenarios where performance and environmental requirements are not high due to the performance of the prior art AWG compared to Z-BLOCK. .

In recent years, with the rapid development and widespread popularization of big data, cloud storage/services, Internet of Things, AR/VR, and mobile Internet terminal devices, the global demand for network bandwidth has shown explosive growth, which has not only greatly promoted the Internet giants and communication operators have increased their investment in data center construction, and it has also accelerated the arrival of the 5G era. As one of the core devices in the field of optical communications, optical transceivers have seen a sharp increase in market demand in recent years. At present, 100G optical transceivers based on CWDM4 technology have become the mainstream of the market, and 400G optical transceivers based on CWDM4 and CWDM8 will become the next generation products in the next few years. While the market demand for optical transceivers is rising rapidly, prices and energy consumption are decreasing accordingly. Low cost, low energy consumption, and small-scale integration are the development directions of optical transceivers. Especially in the application of 5G fronthaul, optical transceivers are also required to meet industrial-grade standards to meet the harsh outdoor environmental requirements. As the core optical components of optical transceivers, WDM optical receiving components meet the industry standards while pursuing low-cost, small-scale integration and high performance at the same time are the constant development trend in the future.

Summary of the invention

In view of the existing technology, the purpose of the present invention is to provide a miniaturized wave division multiplexing optical receiving assembly and an assembly method thereof that are easy to assemble, low cost, high performance, and can realize mass production automation.

In order to achieve the above technical objectives, the technical solutions adopted by the present invention are:

A miniaturized wave division multiplexing optical receiving component, which includes:

Fiber collimator, used to input collimated signal light;

The wavelength division multiplexing sub-assembly is used to demultiplex the signal light input by the fiber collimator into several collimated lights;

Right-angle prism, the right-angled surface of which is opposite to the output end of the WDM sub-component and is used to receive several beams of collimated light decomposed by the WDM sub-component, and then after being reflected by the inclined surface, the several beams of collimated light Output from the other right-angle surface of the right-angle prism; it can also be replaced by a non-right-angle prism to realize the function of the right-angle prism;

The lens array is arranged on the two right-angled faces or one of the right-angled faces of the right-angle prism;

Optical substrate for relatively fixed installation of fiber collimator, wavelength division multiplexing sub-assembly and right-angle prism.

Further, the optical fiber collimator is also connected with an optical fiber ferrule assembly.

Preferably, the optical fiber ferrule assembly is an LC socket or an LC connector, but it is not limited to these two.

Among them, the optical fiber collimator is composed of an optical fiber head, a collimating lens and a sleeve; the optical fiber head can be a glass optical fiber head or a ceramic optical fiber head, the end surface of which is ground and polished. In order to improve the return loss (RL) index, you can choose Processed into an angle of 4 degrees to 9 degrees, the end face can be optionally coated with antireflection coating; the collimating lens is a plano-convex glass lens, in order to improve the RL index, the flat end can be selected to be processed into an angle of 4 degrees to 9 degrees to angle with the fiber head Matching, flat and convex surfaces are coated with antireflection coating; the sleeve is a glass sleeve or a metal sleeve; the optical fiber head and the collimating lens are assembled in the same sleeve by glue to form a collimator.

Further, the wavelength division multiplexing sub-component is Z-Block, and its output end has several filters or filter films with different working wavelengths, which includes parallelogram glass plates with polished front and back sides, and the front side of the glass plate They include areas coated with anti-reflection coating and high-reflection coating, and several areas on the back side are respectively coated with multiple (typically 4 or 8) WDM (wavelength division multiplexing) filter films of different wavelengths or stickers Multiple (usually 4 or 8) filters coated with WDM filter films of different wavelengths. By designing the incident angle and pitch of the Z-Block, the size of the Z-Block can be miniaturized , The incident angle of Z-Block ranges from 3 degrees to 45 degrees, usually 8 degrees or 13.5 degrees, and the pitch ranges from 0.25mm to 2mm.

Preferably, the lens array includes a plurality of plano-convex lenses corresponding to the filter film or the filter on the Z-Block, and the plane side of the plano-convex lens is connected with the right-angle prism, and the lens array includes a plurality of ( Usually 4 or 8) high-precision pitch plano-convex lenses. The material is usually Si or fused silica. It is usually realized by photolithography or molding. The pitch ranges from 0.25mm to 2mm. The convex surface of the lens It is coated with anti-reflection film for air, and the plane is coated with anti-reflection film for glue.

Preferably, an anti-reflection film is provided on the connecting surface of the lens array and the right-angle prism.

Preferably, the Z-Block is a four-channel Z-Block or an 8-channel Z-Block.

Further, the optical substrate is made of glass, silicon or ceramic materials.

Further, the right-angle prism is formed of Si material or glass material, and the angle of the right-angle prism is designed according to the different refractive index of the material to ensure that the emitted light forms a certain angle with the normal of the emission surface, and the angle ranges from 4 degrees to 10 degrees. This is beneficial to improve the RL index of the system. One surface of the right-angle prism and the plane of the lens array are glued together. The glue can be thermal curing glue or dual curing glue (curable by ultraviolet curing and thermal curing). The two right-angled surfaces of the right-angle prism, wherein the surface cemented with the lens array is coated with anti-reflection coating or not coated (the refractive index of the lens array matches the refractive index of the glue), and the other surface is coated with the anti-air The anti-reflection coating, when the two right-angled surfaces are connected with the lens array, the anti-reflection coating is provided. In addition to the mutually bonded structure, the right-angle prism and the lens array can be made into a whole by an etching or molding process, and an air antireflection coating is plated on the incident surface and the exit surface respectively;

Alternatively, the aforementioned right-angle prism can also be replaced by a non-right-angle prism, which can realize all the functions of the aforementioned right-angle prism.

The optical substrate is an optical material, such as glass or silicon, or a ceramic material substrate, and a series of high-precision position alignment lines can be produced on the substrate according to the design by methods such as laser marking or photoetching mask;

The optical fiber collimator, the wave division multiplexing subassembly and the right-angle prism attached to the lens array are adjusted and aligned with the position alignment line on the substrate respectively. After the alignment is completed, they are quickly and accurately fixed with glue , Assembled on the substrate, the glue can choose ultraviolet curing glue or dual curing glue.

A method for assembling a miniaturized wave division multiplexing optical receiving component, which includes the following steps:

(1) Mark the position on the fiber collimator where the emitted light is completely parallel to the bottom surface of the sleeve and the corresponding angle Δφ deviated by 90 degrees;

(2) Alignment lines processed by laser marking or photolithography masking on the optical substrate;

(3) The wave division multiplexing sub-assembly and the right-angle prism bonded with the lens array are bonded and fixed on the optical substrate according to the position of the alignment line;

(4) Rotate the fiber collimator according to the calibrated position to Δφ to compensate for the angle deviation, and then fix it with the optical substrate.

The functions that can be realized by the present invention are: the multi-wavelength wavelength division multiplexing (WDM) signal connected from one end of the optical fiber ferrule assembly is collimated through the optical fiber collimator, and after the WDM collimated light enters the WDM subassembly It is demultiplexed into multiple single-wavelength collimated lights with the same pitch. Multiple single-wavelength collimated lights with the same pitch enter the lens array and right-angle prism with corresponding high-precision pitch, and then pass through the focus and right-angle prism of the lens. The reflection of the inclined surface focuses multiple signal lights on the receiving surface of the photodiode array (PD array) with the same pitch as the lens array, and finally realizes the conversion of photoelectric signals.

Through the above technical solutions, compared with the prior art, the present invention has the following beneficial effects:

The sub-component of the present invention can be compact and miniaturized according to the assembly layout; by optimizing the design of the collimating lens, lens array and right-angle prism parameters of the fiber collimator, selecting the material with the best refractive index can greatly improve the receiving assembly It can reduce the difficulty of assembly of components, including achieving key indicators such as low insertion loss, low crosstalk, and high return loss. Compared with the AWG wave decomposition multiplexing receiving component in the prior art, the present invention has significant performance advantages such as small wavelength variation with temperature, high passband bandwidth, low insertion loss, low crosstalk, etc., and fully meets the industry-level requirements and standards in the industry. In particular, it can meet the harsh requirements of 5G fronthaul application scenarios for industrial-grade environmental conditions of optical devices.

The assembly method of the present invention can adopt the assembly method of directly performing passive alignment of the sub-components and the substrate alignment line, which is compared with the prior art single-chip filter and single-chip lens active (active) alignment adjustment The assembly method of the present invention is simple, efficient, and low in cost, can realize automated assembly and mass production, and can meet the large-scale commercial demand of the components of the present invention in data centers and future 5G optical transceivers.

Description of the drawings

The scheme of the present invention will be further described below in conjunction with the drawings and specific implementations:

Figure 1 is a typical Transceiver structure in the prior art, which contains a pair of independent MUX and DEMUX;

Figure 2 is a typical Z-BLOCK structure diagram in the prior art;

3 is a schematic diagram of the 3D structure of Embodiment 1 of the present invention;

4 is a schematic diagram of a top view structure and optical path of Embodiment 1 of the present invention;

5 is a schematic side view of the structure of Embodiment 1 of the present invention;

Fig. 6 is an enlarged schematic diagram of a partial structure at A in Fig. 5;

7 is a schematic top view of a modified structure of Embodiment 1 of the present invention;

8 is a schematic side view of a modified structure of Embodiment 1 of the present invention;

FIG. 9 is a schematic top view of the structure of Embodiment 2 of the present invention;

10 is a schematic side view of the structure of Embodiment 2 of the present invention;

11 is a schematic top view of a modified structure of Embodiment 2 of the present invention;

12 is a schematic side view of a modified structure of Embodiment 2 of the present invention;

13 is a schematic top view of the structure of Embodiment 3 of the present invention;

14 is a schematic side view of the structure of Embodiment 3 of the present invention;

Fig. 15 is an enlarged schematic diagram of a partial structure at A in Fig. 14;

16 is a schematic diagram of a convex sunk lens array in the scheme of the present invention;

FIG. 17 is a schematic top view of the structure of Embodiment 4 of the present invention;

18 is a schematic side view of the structure of Embodiment 4 of the present invention;

Fig. 19 is an enlarged schematic diagram of a partial structure at A in Fig. 18;

20 is a schematic top view of the structure of Embodiment 5 of the present invention;

21 is a schematic side view of the structure of Embodiment 5 of the present invention;

FIG. 22 is an enlarged schematic diagram of the partial structure at A in FIG. 21.

Detailed ways

In order to make the objectives, technical solutions, and advantages of the present invention clearer, the following further describes the present invention in detail with reference to the accompanying drawings and implementation examples. It should be understood that the specific implementation examples described here are only used to explain the present invention, but not to limit the present invention.

Example 1

As shown in one of Figures 3 to 6, a miniaturized wave division multiplexing optical receiving component of the present invention includes:

Optical fiber collimator 1, for inputting collimated signal light;

Wavelength division multiplexing sub-assembly 2 for de-multiplexing the signal light input by the fiber collimator into several collimated lights;

Right-angle prism 3, its right angle surface is opposite to the output end of the wave division multiplexing sub-assembly and is used to receive several beams of collimated light decomposed by the wave division multiplexing sub-assembly, and then after being reflected by its inclined surface, the several beams are collimated The light is output from the other right-angle surface of the right-angle prism;

The lens array 4 is arranged on a right-angled surface of the right-angled prism 3, and the right-angled surface is a right-angled surface opposite to the wave decomposition multiplexing subassembly 3;

The optical substrate 5 is used for relatively fixed installation of the fiber collimator 1, the wavelength division multiplexing subassembly 2 and the right angle prism 3.

Wherein, the optical fiber collimator 1 is also connected with an optical fiber ferrule assembly 6; preferably, the optical fiber ferrule assembly 6 is an LC socket or an LC connector, but it is not limited to these two.

In addition, the optical fiber collimator is composed of an optical fiber head, a collimating lens and a sleeve; the optical fiber head can be a glass optical fiber head or a ceramic optical fiber head, the end face of which is ground and polished. In order to improve the return loss (RL) index, you can choose Processed into an angle of 4 degrees to 9 degrees, the end face can be optionally coated with antireflection coating; the collimating lens is a plano-convex glass lens, in order to improve the RL index, the flat end can be selected to be processed into an angle of 4 degrees to 9 degrees to angle with the fiber head Matching, flat and convex surfaces are coated with antireflection coating; the sleeve is a glass sleeve or a metal sleeve; the optical fiber head and the collimating lens are assembled in the same sleeve by glue to form a collimator.

In this embodiment, the wavelength division multiplexing sub-assembly 2 is a 4-channel Z-Block, and its output end has several filters 21 or filter films with different working wavelengths, which include parallelograms with polished front and rear sides. Glass plate, the front side of the glass plate contains areas coated with anti-reflection coating and high-reflection coating, and several areas on the back side are respectively coated with 4 different wavelength WDM (wavelength division multiplexing) filter films or pasted with 4 The filters are respectively coated with WDM filter films of different wavelengths. By designing the incident angle and pitch of the Z-Block, the size of the Z-Block can be miniaturized. The incident angle of the Z-Block is usually 8 degrees. Or 13.5 degrees, the pitch range is from 0.25mm to 2mm; preferably, the lens array 4 includes a number of plano-convex lenses corresponding to the Z-Block upper filter film 21 or the filter, and the plane of the plano-convex lens The side is connected with a right-angle prism, the lens array contains 4 high-precision pitch plano-convex lenses, the material is usually Si or fused silica, and is usually realized by photolithography or molding process, the pitch range is from 0.25mm Up to 2 mm, the convex surface of the lens is coated with an anti-reflection coating for air, and the plane is coated with an anti-reflection coating for glue; preferably, an anti-reflection coating is provided on the connecting surface of the lens array and the right-angle prism.

Further, the optical substrate is glass or silicon, or ceramic material substrate, and a series of high-precision position alignment lines can be produced on the substrate by laser marking or photolithography masking methods.

Further, the right-angle prism is formed of Si material or glass material, and the angle of the right-angle prism is designed according to the different refractive index of the material to ensure that the emitted light forms a certain angle with the normal of the emission surface, and the angle ranges from 4 degrees to 10 degrees. This is beneficial to improve the RL index of the system. One surface of the right-angle prism and the plane of the lens array are glued together. The glue can be thermal curing glue or dual curing glue (curable by ultraviolet curing and thermal curing). The two right-angled surfaces of the right-angle prism, wherein the surface cemented with the lens array is coated with an anti-reflection coating for anti-reflection coating, and the other surface is coated with an anti-reflection coating for air. When the two right-angled surfaces are connected with the lens array, then Both are equipped with antireflection coating. In addition to the mutually bonded structure, the right-angle prism and the lens array can be made into a whole by an etching or molding process, and an air antireflection coating is plated on the incident surface and the exit surface, respectively.

In this embodiment, WDM optical signals with center wavelengths of 1271nm, 1291nm, 1311nm and 1331nm are connected from the standard fiber ferrule assembly 6 LC Receptacle on the left, and after passing through the fiber collimator 1, they become collimated beams. The design of direct light beam waist diameter is usually between 150 microns and 300 microns; the collimated beam enters the Z-BLOCK AR coated area at an incident angle of 13.5 degrees and enters the Z-BLOCK, after passing through the Z-BLOCK , 4 wavelengths of WDM signals are demultiplexed into 4 collimated beams, the pitch between each of the 4 beams is 750 microns; 4 beams of collimated light with a pitch of 750 microns enter and paste at right angles In the coupling lens array in front of the prism, the pitch and tolerance of the lens array is 750+/-1 micron. After passing through the lens array, the collimated beam becomes a convergent beam, then passes through the total reflection of the inclined surface of the prism, transmits downward, and finally emits On the bottom surface of the prism, the angle between the emitted light and the normal line of the bottom surface of the prism is 6°～10°, and then it is focused on the focal plane of the lens array. A PD array with a pitch of 750+/-1 microns is usually placed on the focal plane. The light is efficiently coupled into the effective area of the PD array to realize the conversion of photoelectric signals.

In this embodiment, by designing the focal length difference between the collimating lens and the coupling lens of the optical fiber collimator 1, the best focal spot beam waist size can be theoretically obtained. For example, the mode field diameter of the optical fiber is 8.6 microns, the focal length of the designed collimating lens is 1.2mm, and the focal length of the coupling lens array is 1mm. Theoretically, the beam waist diameter of the focal point can be 8.6/1.2=7.167 microns. The effective coupling area diameter of some high-speed receiving PD arrays is much smaller than 16 microns, which helps to reduce assembly tolerance and sensitivity requirements. It should be noted that the beam waist of the focus point should not be too small, too small will cause the divergence angle of the beam to be too large, which will cause the size of the focus spot to increase rapidly with the change in the front and back distance of the focal plane, which will greatly increase the system The coupling sensitivity is not conducive to assembly.

In this embodiment, since the focusing lens array 4 has a very high-precision pitch, it is ensured that the four parallel lights exiting from the Z-BLOCK with good parallelism can be focused by the lens array. Later, the accuracy of the spacing between the center points of the four light spots is very high. Normally, the PD array at the receiving end also has the same high-precision pitch, which ensures that the center points of the four focus spots all enter the central area of the effective area of the PD array.

In this embodiment, the refractive index of the material of the prism can be selected to extend or shorten the length of the back focal length of the coupling lens array, so that the assembly structure is more reasonable. For example, compared to the use of a Si prism with a refractive index of about 3.5 and a borosilicate glass prism with a refractive index of about 1.5, for the same coupling lens, when the effective focal length (EFL) is the same, the back focal length of the Si prism Will be longer. It can be understood that if the distance from the lens array to the focal plane is constant, if the Si prism is used, the effective focal length of the corresponding coupling lens can be shorter; because the position of the spot on the focal plane changes Δd and the effective focal length f and angle deviate θ The relationship between Δd=f*tan(θ), when θ is very small, Δd=f*θ, therefore, a short effective focal length means that the smaller the displacement of the spot with the angle, that is, the greater the angular sensitivity Lower, the lower the alignment requirements for assembly.

The assembly method of the structure of this embodiment is:

The entire assembly process of this embodiment can be completed by means of automatic alignment and angle correction, with high assembly efficiency and low cost.

In this embodiment, the fiber collimator 1, the Z-BLOCK (ie, the wave division multiplexing subassembly 2), the right-angle prism 3 with the lens array 4 and the optical substrate 5, the overall size can be achieved after assembly The length, width, and height do not exceed 11×3.7×1.95mm. This size is smaller than the assembly of the AWG wave decomposition and multiplexing receiving component of the same pitch, and it is completely a miniaturized component.

Focusing on Figs. 7 and 8, as a modified structure of this embodiment, the length of the optical substrate 5 is lengthened in this embodiment. The material of the optical substrate 5 is optical glass or Si material, so that the light reflected by the right-angle prism 3 is emitted. It enters and passes through the optical substrate 5, and then focuses on a focal plane with a slight distance from the substrate. This deformed structure can be applied to directly couple optical signals into a grating coupler, and then into a waveguide, and the remaining components are the same as the structure shown in Figs. 3-6.

Example 2

Referring to Figures 9 and 10, this embodiment is roughly the same as Embodiment 1, and is different from Embodiment 1 in that the 4-channel Z-BLOCK becomes 8-channel Z-BLOCK, and the center wavelength can be 1271nm, 1291nm, 1311nm, 1331nm, 1351nn, 1371nm, 1391nm and 1411nm, a total of 8 wavelengths are wave-decomposed and multiplexed, and the corresponding 4-channel lens array becomes 8 channels accordingly. This structure meets the requirements for high-performance and miniaturized wave decomposition and multiplexing receiving components in 400G OSFP optical transceivers, and the remaining components are the same as the structures shown in Figures 3-6.

Referring to Figures 11 and 12, as a modified structure of this embodiment, the length of the optical substrate 5 is lengthened in this embodiment. The material of the optical substrate 5 is optical glass or Si material, so that the light reflected by the right-angle prism 3 enters It passes through the optical substrate 5 and then focuses on a focal plane with a small distance from the substrate. This deformed structure can be applied to directly couple optical signals into a grating coupler, and then couple into a waveguide.

The installation implementation of this embodiment is the same as that of Embodiment 1, and will not be repeated here.

Example 3

Referring to Figures 13 to 15, this embodiment is roughly the same as Embodiment 1. In this embodiment, the only difference from Embodiment 1 is that the lens array 4 is attached to the exit surface of the right-angle prism 3. At this time, you can choose The lens array 4 with a shorter focal length can obtain a smaller spot size on the focal plane. This structure can satisfy applications with a small PD receiving area. At this time, the thickness of the optical substrate can be strictly controlled to ensure that the position of the focal plane of the focused spot coincides with the position of the PD receiving surface.

In order to achieve a smaller phase difference, when selecting a lens array, a convex recessed lens array (Recession Lens Array) as shown in FIG. 16 can be used. At this time, the convex steps can be attached to the exit surface of the prism.

Example 4

Referring to Figures 17 to 19, this embodiment is roughly the same as Embodiment 3. In this embodiment, the difference from Embodiment 3 is that the 4-channel Z-BLOCK becomes 8-channel Z-BLOCK, and the corresponding 4-channel lens array is also It becomes 8 channels.

In order to achieve a smaller phase difference, when selecting a lens array, this embodiment may also use the recession lens array shown in FIG. 16 (Recession Lens Array). At this time, the convex steps can be attached to the exit surface of the prism.

Example 5

20-22, this embodiment is a combination of embodiment 2 and embodiment 4. A lens array 4 (increasing a lens array with a long focal length (located on the incident surface) and a lens array with a short focal length are provided on the front and back of the right-angle prism 3, respectively (Located on the exit surface)). Through a long focal length lens array (usually called a weak lens array), the collimated beam can be converged and reduced, and then the convergent beam reflected by the inclined surface of the right-angle prism 3 enters the short focal length lens array, and finally focuses on the focal plane on.

This embodiment can focus the light spot to a small size, and since the light beam is converged, the sensitivity of the light spot size to changes in the front and back positions of the focal plane is very low, which is more suitable for OSFP wavelength division multiplexing light receiving components.

In order to achieve a smaller phase difference, when selecting a lens array, this embodiment may also adopt a convex recessed lens array (Recession Lens Array). At this time, the steps of the convex surface can be attached to the exit surface of the prism.

It should be noted that the part numbers marked in FIGS. 3 to 22 are the same parts with the same names.

Although the present invention has been specifically shown and described in conjunction with the preferred embodiments, those skilled in the art should understand that the present invention is made in form and detail without departing from the spirit and scope of the present invention as defined by the appended claims. The various changes presented are within the protection scope of the present invention.

Claims

A miniaturized wave division multiplexing optical receiving component, which is characterized in that it includes:

Fiber collimator, used to input collimated signal light;

The wavelength division multiplexing sub-assembly is used to demultiplex the signal light input by the fiber collimator into several collimated lights;

Right-angle prism, the right-angled surface of which is opposite to the output end of the WDM sub-component and is used to receive several beams of collimated light decomposed by the WDM sub-component, and then after being reflected by the inclined surface, the several beams of collimated light Output from the other right-angle surface of the right-angle prism;

The lens array is arranged on the two right-angled faces or one of the right-angled faces of the right-angle prism;

Optical substrate for relatively fixed installation of fiber collimator, wavelength division multiplexing sub-assembly and right-angle prism.
The miniaturized WDM optical receiving assembly according to claim 1, wherein the optical fiber collimator is further connected with an optical fiber ferrule assembly.
The miniaturized WDM optical receiving assembly according to claim 2, wherein the optical fiber ferrule assembly includes an LC or SC socket, and an LC or SC connector.
The miniaturized wavelength division multiplexing optical receiving component according to claim 1, wherein the wavelength division multiplexing sub-component is a Z-Block, and its output end has several filters with different working wavelengths. Or filter film.
A miniaturized WDM light receiving component according to claim 4, wherein the lens array includes a number of plano-convex lenses corresponding to the Z-Block upper filter film or filter one-to-one, And the plane side of the plano-convex lens is connected with the right-angle prism.
The miniaturized WDM light receiving component according to claim 4, wherein the connecting surface of the lens array and the right-angle prism is provided with an anti-reflection film or no coating.
The miniaturized WDM optical receiving component of claim 4, wherein the Z-Block is a four-channel Z-Block or an 8-channel Z-Block.
The miniaturized WDM light receiving component according to claim 1, wherein the optical substrate is made of glass, silicon or ceramic materials.
The miniaturized WDM light receiving assembly according to claim 1, wherein the right-angle prism is formed of Si material or glass material.
A method for assembling a miniaturized WDM optical receiving component according to claim 1, characterized in that it comprises the following steps:

(1) Mark the position on the fiber collimator where the emitted light is completely parallel to the bottom surface of the sleeve and the corresponding angle Δφ deviated by 90 degrees;

(2) Alignment lines processed by laser marking or photolithography masking on the optical substrate;

(3) The wave division multiplexing sub-assembly and the right-angle prism bonded with the lens array are bonded and fixed on the optical substrate according to the position of the alignment line;

(4) Rotate the fiber collimator according to the calibrated position to Δφ to compensate for the angle deviation, and then fix it with the optical substrate.