61 results about "Single mode waveguides" patented technology

An electro-optic modulator includes a light-splitting element, a light-combining element, two waveguide arms, and a modulation electrode. The two waveguide arms are connected between the light-splitting element and the light-combining element, and each waveguide arm includes a first single-mode waveguide portion, a first coupling portion, a multi-mode waveguide portion, a second coupling portion, and a second single-mode waveguide portion, wherein the width of either of the first single-mode waveguide portion and the second single-mode waveguide portion is smaller than the width of the multi-mode waveguide portion; the first coupling portion is configured to enable light to be coupled into the multi-mode waveguide portion from the first single-mode waveguide portion, and the second coupling portion is configured to enable light to be coupled into the second single-mode waveguide portion from the multi-mode waveguide portion; and the modulation electrode is configured to apply a modulation voltage to the multi-mode waveguide portion of the two waveguide arms.

The invention relates to a micro-ring resonator based on a multi-circle square structure, the micro-ring resonator comprises a coupling waveguide and a multi-circle square micro-ring resonant cavity, the coupling waveguide comprises an S-bend waveguide, an input waveguide and an output waveguide which are all single-mode waveguides, and the multi-circle square micro-ring resonant cavity comprises a crossed waveguide chain and a multi-mode waveguide section connected with the crossed waveguide chain. The multi-mode waveguide section comprises a multi-mode straight waveguide and a 90-degree multi-mode Euler bending waveguide. By introducing the multi-mode waveguide, the energy distribution of the guided mode on the side wall is reduced, and the transmission loss of the micro-ring resonant cavity is reduced. Through the arrangement of the multi-circle square micro-ring resonant cavity, the length of the micro-ring is increased within a limited size, and the Q value of the multi-circle square micro-ring resonant cavity is improved. By means of the 90-degree multimode Euler bending waveguide, compact 90-degree turning is achieved, generation of a high-order mode is restrained, and meanwhile the micro-ring surrounding area is increased. Therefore, a solution can be provided for the high-performance sensing unit for the integrated micro-ring sensor.

The invention relates to a polarization independent conversion device of a cascade mode conversion waveguide, and belongs to the field of semiconductor optical signal transmission. The device comprises a substrate of a wafer, a buried oxide layer of the wafer, a device layer and a SiO2 upper cladding layer of the device layer from bottom to top. The device layer comprises an input waveguide, a mode evolution waveguide, a multi-section conical mode conversion waveguide, a polarization beam splitting rotator and a light beam combiner assembly. The mode evolution waveguide realizes high-order conversion from a TM0 mode to a TE1 mode; the multi-section conical mode conversion waveguide converts a TM mode of an optical signal in the input waveguide into a TE mode, and the mode coupling ratio is improved by sequentially superposing the conversion ratio of the TM mode; the phase shifter is used for ensuring that the phase difference of two columns of combined waves is 0; and the light beam combining assembly is used for combining the two columns of TE mode light signals and finally outputting a single-mode waveguide TE mode. According to the invention, TE0 single-mode beam combination output irrelevant to any polarization state of an input optical signal is realized, the structure is simple and compact, and the device is suitable for large-scale integration.

The invention provides an electro-optical modulator combining a slow light waveguide and a capacitive load type traveling wave. The electro-optical modulator comprises the slow light waveguide, a capacitive load type traveling wave electrode, a multi-mode interferometer, a mixed single-mode waveguide, a micro-ring structure and a micro-ring upper phase adjusting electrode. Capacitive load type traveling wave electrodes are arranged between and on the side edges of a pair of slow light waveguides which are arranged in parallel, the two ends of the slow light waveguides are connected to one end of a multimode interferometer through mixed single-mode waveguides respectively, the other end of the multimode interferometer is provided with two ports, one port is used for being connected with a micro-ring structure, and the other port is used for being connected with a micro-ring structure. The other port is used as the input end or the output end of the electro-optical modulator, and the two sides of the micro-ring structure are provided with micro-ring upper phase adjusting electrodes. The group refractive index and the working bandwidth of light can be regulated and controlled by adjusting the geometric parameters of the slow light waveguide, and low dispersion and high group refractive index can be realized in a wide optical bandwidth range; through a sectional capacitance load type slow wave electrode structure, the regulation and control of the microwave refractive index are realized, and the electro-optical modulation bandwidth is improved.

The invention relates to a dispersion compensation annular reflector and a preparation method thereof. Comprising a substrate, a silicon waveguide core layer arranged on the substrate, and a first 1 * 2 multimode interferometer, a first bent conical waveguide, a second bent conical waveguide, a first mode converter, a second mode converter and a first coupling waveguide which are arranged on the silicon waveguide core layer, the first end and the second end of the first 1 * 2 multi-mode interferometer are respectively provided with a port and two ports, and the port of the first end is connected to the section of the incident and emergent waveguide through the first single-mode waveguide; the two ports of the second end are connected to the input ends of the first mode converter and the second mode converter through the first bent conical waveguide and the second bent conical waveguide respectively, and the output ends of the first mode converter and the second mode converter are connected through the first coupling waveguide. The device provided by the invention can be adapted to various material platforms, and has good integration with other devices.

The invention discloses a method for preparing a low-loss sharp-bend waveguide through femtosecond laser in-situ multi-time modification, belongs to the technical field of laser processing, and adopts femtosecond laser in-situ multi-time modification to accurately optimize the problem of large bending loss of a 90 sharp-bend waveguide in single direct writing. The main principle is as follows: femtosecond laser is focused in a material by controlling a high-precision three-dimensional motion platform, and femtosecond laser processing energy and laser scanning speed are adjusted to reach preparation conditions of a single-mode waveguide; and performing in-situ multi-time modification regulation and control on waveguide performance by using femtosecond laser to prepare 90 low-loss sharp-bend waveguides with different bending radiuses. In-situ multiple modification enables the structure of the material modified by laser in the material to be more compact, the refractive index of the core layer of the waveguide is increased, and radiation loss can be inhibited; in-situ multi-time modification can also drive foreign ions in the waveguide to migrate to the waveguide boundary, scattering and absorption of light by the foreign ions are reduced, and absorption and scattering loss of the waveguide is reduced. The method is simple in preparation process, high in reliability and easy to implement.

An optical device includes a transition unit in which a first waveguide and a second waveguide are disposed in an overlapped manner such that a magnitude relationship of an effective refractive index between the vertical modes propagating the first waveguide and the vertical modes propagating the second waveguide is inverted at the positions of input and output. The transition unit allows, at the input, the second waveguide to be a single mode waveguide and allows, at the output, the second waveguide to be a multi-mode waveguide through which TM0 light in the maximum vertical mode and light in a higher-order mode propagate. The optical device includes a removing unit that allows the second waveguide to be a single mode waveguide through which the TM0 light propagates by removing the light in the higher-order mode from the light received from the transition unit.

A photonics device is described. The photonics device includes a waveguide and an electrode. The waveguide configured to transmit an optical signal having a wavelength less than 1100 nanometers and is a single mode waveguide. The waveguide includes electro-optic material(s). The electrode is proximate to a portion of the waveguide and configured to carry an electrode signal for modulating the optical signal. The photonics device is configured to be coupled with at least one multimode fiber. The multimode fiber(s) is configured to transmit a plurality of modes.

The invention discloses a calculation reconstruction spectrum detection device and method based on metal particle scattering. The device comprises an input system, a multi-mode waveguide, metal particles and a two-dimensional photoelectric detector, the input system is a single-mode waveguide, light is injected into the multi-mode waveguide after being stably transmitted in the input system, and the metal particles are randomly distributed on the upper surface of the multi-mode waveguide and can scatter and output the transmitted light in the multi-mode waveguide from the upper surface. Therefore, the incident light spectrum is detected by the two-dimensional photoelectric detector placed above the multimode waveguide, and high-precision and high-resolution reconstruction of the incident light spectrum can be realized. Compared with an existing defect scattering mode, metal nanoparticle scattering has more sensitive wavelength response, so that the method has better performance; in addition, processing of the device is more convenient than that of a defect scattering type device. Compared with a traditional commercial spectrograph, the device has the advantages of being few in device, compact in structure and small in size, the system complexity and cost of the spectrograph are effectively reduced, and the portability of the spectrograph is improved.

The invention discloses a marine salinity sensor based on on-chip integrated waveguide multimode interference and a manufacturing method. The marine salinity sensor comprises a silicon-based substrate, a waveguide lower cladding, a waveguide upper cladding, a single-mode waveguide core layer and a few-mode waveguide core layer, the single-mode waveguide core layer is connected with the introduction single-mode optical fiber; the few-mode waveguide core layer is connected with the leading-out single-mode optical fiber; the waveguide upper cladding is provided with a detection port for promoting external liquid to directly contact with the surface of the few-mode waveguide core layer; an optical signal is input from the leading-in single-mode optical fiber, is coupled with the at least-mode waveguide core layer through the single-mode waveguide core layer, and after entering the few-mode waveguide core layer, the optical signal excites a plurality of modes, generates inter-mode interference and then returns to the single-mode waveguide core layer to be output; the salinity change of the external liquid enables the refractive index of the liquid to change, and then the effective mode refractive index in the few-mode waveguide core layer is influenced, so that the output spectrum drifts, and the salinity information of the liquid can be inverted based on the spectrum drift amount.

This invention discloses a highly integrated mode filter and its fabrication method, comprising a silicon substrate, a lower cladding layer, and an upper cladding layer, with a core layer between the upper and lower cladding layers. The core layer includes an input waveguide, a first mode routing region for filtering out the fundamental mode and converting higher-order modes into the fundamental mode for output, a single-mode region for transmitting the single-mode waveguide in the first mode routing region, a second mode routing region for converting the fundamental mode transmitted in the single-mode region into higher-order modes, and an output waveguide. The waveguide inputs from the incident port and propagates through the left-side first mode routing region, where the fundamental mode TE0 is filtered out by the curved waveguide; the higher-order mode TE1 is converted into the fundamental mode TE0 through the left-side first mode routing region, propagates through the central straight waveguide to the right-side second mode routing region, is converted into the higher-order mode TE1, and then outputs from the output port via the output waveguide. This mode filter is simple to fabricate, small in size, has excellent performance, low processing cost, high mode conversion rate, and strong anti-crosstalk capability. It selectively filters out some modes of light, improving the quality and stability of optical communication.

The invention relates to an optical waveguide array structure based on multimode optical fibers and a design method thereof, the optical waveguide array structure comprises a plurality of optical waveguide composite structures arranged along the length direction, and each optical waveguide composite structure comprises a first bent waveguide, a first linear waveguide and a plurality of single-mode waveguide structures arranged along the length direction; the first bent waveguide and the first linear waveguide are sequentially communicated to form a waveguide guide area; the multiple single-mode waveguide structures form a waveguide selection area, each single-mode waveguide structure is formed by connecting a second linear waveguide and a second bent waveguide, the second linear waveguide and the first linear waveguide form waveguide coupling, and the terminal of the second bent waveguide vertically faces the cladding interface of the multimode fiber. The optical waveguide array with wavelength selectivity and energy consistency is formed by performing parameter adjustment on an optical waveguide structure by inscribing a structure of conducting light waves at different positions of the multimode optical fiber, so that the problem that the wavelength and energy of propagation light are difficult to control in an array structure controlled by a multimode optical fiber light field is solved.

The invention relates to an optical waveguide sensor based on a cascaded phase-shift uniform Bragg grating, and the sensor comprises the cascaded phase-shift uniform Bragg grating which is provided with an input single-mode waveguide and an output single-mode waveguide. A plurality of phase-shift uniform Bragg grating units are arranged between the input single-mode waveguide and the output single-mode waveguide; the phase shift uniform Bragg grating unit comprises a phase shift cavity and periodic refractive index modulation structures symmetrically arranged on the two sides of the phase shift cavity. The optical waveguide structure of the phase shift uniform Bragg grating is not covered by an upper cladding. According to the invention, through the coupling design of cascaded multi-stage harmonic peaks, the quality factor and the detection precision are greatly improved, and the wavelength detection range is widened at the same time. The design without the upper cladding layer is combined with the single-step photoetching etching process, so that the complex process of growing the upper cladding layer or overlaying a sensing window is thoroughly omitted, and the manufacturing cost and the process complexity are greatly reduced.

A binary photonics lattice that includes a waveguide array having a plurality of single mode waveguides disposed in a substrate, the plurality of single mode waveguides including one or more first waveguides having a first V-number V1 and one or more second waveguides having a second V-number V2. The first V-number V1 is smaller than the second V-number V2. The one or more first and second waveguides are arranged in a linear distribution having first and second edge waveguide regions and a binary waveguide region positioned between the first and second edge waveguide regions. The binary waveguide region is a symmetrical binary representation of a decimal number of two or greater. Further, the binary waveguide region includes at least one first waveguide representing a digit 0 of the symmetrical binary representation and / or at least one second waveguide representing a digit 1 of the symmetrical binary representation.

The present disclosure provides a four-port multimode router and a link switching network. The four-port multimode router includes four multimode input waveguides; four mode demultiplexers, the mode demultiplexers are suitable for converting a multimode multiplexed signal into N single-mode signals, wherein N is a positive integer; four single-mode input waveguide groups, each of which includes N single-mode input waveguides, and the input ends of the N single-mode input waveguides are connected to the N output ends of a mode demultiplexer; the same input end of N 4×4 single-mode optical routing units is connected to the N single-mode waveguide output ends of a single-mode input waveguide group; four single-mode output waveguide groups, each of which includes N single-mode output waveguides, and the input ends of the N single-mode output waveguides are respectively connected to the same output end of each 4×4 single-mode optical routing unit; four mode multiplexers, each of which has an input end connected to the output end of the N single-mode output waveguides of a single-mode output waveguide group; and four multimode output waveguides.

The invention discloses a coupling coefficient measurement method based on an identical waveguide array, and belongs to the field of optical waveguide property measurement and test, and the method comprises the steps: building a waveguide array coupling coefficient measurement system; testing an evolution result of the waveguide array; reversely deducing a coupling coefficient through a simulation experiment; according to the invention, based on the consistency of the evolution process of photons in a waveguide array and quantum walking in continuous time, an identical single-mode waveguide array is adopted, according to a physical model of quantum walking in continuous time, output probability amplitudes under different evolution lengths are measured, and a least square method is combined to evaluate simulation and test results; and finally obtaining the coupling coefficient of the waveguide. The method is low in requirement on experimental equipment, small in workload and less in required sample width; and the evolution condition of the light in the waveguide array can be accurately predicted and analyzed.

The present disclosure provides a mode spot converter and a preparation method thereof, which are used for directly coupling an optical fiber and a photoelectric detector chip. The mode spot converter comprises a substrate, a ridge waveguide formed on the substrate, and the ridge waveguide comprises a ridge single-mode waveguide, a tapered ridge waveguide and a widened ridge waveguide connected in sequence along a direction parallel to the surface of the substrate. The widened ridge waveguide is used for connecting an optical fiber and matching the mode field of the optical fiber. The tapered ridge waveguide is used for amplifying and concentrating the mode spot of the light wave output by the optical fiber. The ridge single-mode waveguide is used for coupling the light wave after mode spot conversion to the photoelectric detector chip. The mode spot converter improves the coupling efficiency, accuracy and tolerance, and transmission efficiency, greatly reduces the loss of directly coupling a single-mode optical fiber and a ridge single-mode waveguide, and has high compact integration and low packaging cost.

The invention provides an optical multimode interference coupler. According to the optical multi-mode interference coupler, the transmission waveguide of the slit structure is directly connected with the interface of the strip-shaped multi-mode waveguide, and based on the multi-mode excitation principle and the self-imaging principle of the multi-mode interference coupler, optical signals in the strip-shaped multi-mode waveguide are located at the interface in the slit single-mode waveguide; light splitting in the waveguide and transformation of a waveguide structure are completed at the same time, a traditional gradual deformation strip slit waveguide conversion structure does not need to be used, the length of an electronic component is effectively reduced, and the integration level of the device is improved. According to the invention, an input optical signal can be directly and equally divided into the two slit waveguides from the strip-shaped waveguide, and a traditional combined structure of first light splitting and then conversion is not needed. And the device has the advantages of small size, low loss, high bandwidth and the like.

This invention relates to a dispersion-compensated ring reflector and its fabrication method. It includes a substrate, a silicon waveguide core layer disposed on the substrate, and a first 1×2 multimode interferometer, a first curved tapered waveguide, a second curved tapered waveguide, a first mode converter, a second mode converter, and a first coupling waveguide disposed on the silicon waveguide core layer. The first 1×2 multimode interferometer has one port at its first end and two ports at its second end. The port at the first end is connected to the incident and exit waveguide cross-sections via a first single-mode waveguide. The two ports at the second end are connected to the inputs of the first and second mode converters via the first and second curved tapered waveguides, respectively. The outputs of the first and second mode converters are connected via the first coupling waveguide. The device provided by this invention is adaptable to various material platforms and has good integration with other devices.

This application provides a method and system for detecting the coupling effect of a Fiber Optic Actuator (FAU). In one example, the FAU coupling effect detection system includes: a C-band laser for outputting a C-band laser signal; a C-band circulator for inputting the C-band laser signal into a designated optical fiber of the FAU when the FAU is coupled to a silicon photonic chip, and inputting the reflected light signal of the C-band laser signal into an optical power meter; wherein a C-band grating is disposed in a single-mode waveguide corresponding to the designated optical fiber in the silicon photonic chip; the reflected light signal of the C-band laser signal is obtained by reflecting the input C-band laser signal through the C-band grating; and the optical power meter is used to measure the optical power of the reflected light signal of the C-band laser signal. Applying this embodiment allows for the detection of the coupling effect between the FAU and the silicon photonic chip without adding an additional loopback optical path.

This invention relates to the field of micro-nano optoelectronic device technology, specifically to a multi-stage end-face coupler for interconnecting optical fibers and on-chip photonic integrated devices, comprising a 3×2 multimode interference coupler, a connecting single-mode waveguide, and a 2×1 multimode interference coupler; the 3×2 multimode interference coupler includes three input tapered waveguides, a first multimode waveguide, and a dual-output tapered waveguide connected in sequence; the 2×1 multimode interference coupler includes a dual-input tapered waveguide, a second multimode waveguide, a single-output tapered waveguide, and a single-mode waveguide connected in sequence; the middle input tapered waveguide and the side input tapered waveguides are symmetrically distributed along the optical axis, and the first and second multimode waveguides include an interference region and a transition region, the width of which narrows along the direction of light propagation; this invention can reduce the transmission loss of the end-face coupler, increase the alignment tolerance, and reduce the fabrication difficulty.

The invention discloses an ultra-wideband compact calculation spectrometer structure of an electric tuning single-mode spiral waveguide, and belongs to the technical field of photonic devices and integration, the spectrometer structure is constructed on a silicon platform on an insulating substrate, and the spectrometer structure sequentially comprises a resistive layer, an upper cladding, a waveguide layer, a lower cladding and a substrate layer from top to bottom; the waveguide layer comprises an input waveguide, a spiral waveguide and an output waveguide; the input waveguide and the output waveguide are both single-mode waveguides; the spiral waveguide is a single-mode spiral waveguide; the input waveguide and the output waveguide are both connected with the spiral waveguide through a bent waveguide. The ultra-wideband compact calculation spectrometer structure of the electric tuning single-mode spiral waveguide has the advantages of being large in broadband, high in resolution, small in size, few in physical channel, compatible with a standard tape-out process and the like.

The invention discloses an integrated polarization-maintaining electro-optical non-reciprocal device based on mode evolution coupling filtering and a preparation method thereof.The device structurally comprises a single-mode waveguide, a cascade mode converter, a TE1 / TE0 mode filter and an electro-optical mode coupler, residual light interference is restrained through the synergistic effect of mode evolution and filtering, the electro-optical mode coupler adopts an x-cut lithium niobate thin film waveguide, and the x-cut lithium niobate thin film waveguide is connected with the cascade mode converter. Applying a back propagation microwave signal in combination with a traveling wave electrode, and triggering non-reciprocal mode coupling of the TE0 and the TM0; the cascade multimode interference filter effectively filters residual modes; according to the preparation method, high-precision processing is realized through ion beam etching, electron beam photoetching and electrode integration processes. Under the condition of no magneto-optical material, the forward insertion loss is 10dB, the reverse isolation degree is 20dB, the C-band broadband work is supported, the output polarization extinction ratio is greater than 20dB, and the filter has the characteristics of miniaturization, high process compatibility and excellent anti-interference performance, and is suitable for optical communication and quantum integration systems.

The invention provides a fiber core alignment welding device of a soft glass active optical fiber, which comprises a first monitoring light source, a second monitoring light source, a wavelength division multiplexer, an optical fiber to be welded, a cladding mode stripper, the soft glass active optical fiber, an optical fiber welding machine, a dichroscope, a light spot analyzer and a power meter, the wavelength of the output first monitoring laser is located in an absorption band of the soft glass active optical fiber; a tail fiber of the second monitoring light source is a single-mode optical fiber, the wavelength for outputting the second monitoring laser is located outside the absorption band of the soft glass active optical fiber, and a fiber core of the soft glass active optical fiber is a single-mode waveguide for the second monitoring laser; the dichroscope is used for splitting the first monitoring laser and the second monitoring laser output by the soft glass active optical fiber; and the power meter is used for measuring the power of the first monitoring laser. The invention further provides a fiber core alignment welding parameter optimization method of the soft glass active optical fiber.

The invention relates to the technical field of micro-nano optoelectronic devices, in particular to a multistage end face coupler for interconnection of an optical fiber and an on-chip photonic integrated device, which comprises a 3 * 2 multi-mode interference coupler, a connecting single-mode waveguide and a 2 * 1 multi-mode interference coupler, the 3 * 2 multi-mode interference coupler comprises three input conical waveguides, a first multi-mode waveguide and a dual-output conical waveguide which are connected in sequence; the 2 * 1 multi-mode interference coupler comprises a double-input conical waveguide, a second multi-mode waveguide, a single-output conical waveguide and a single-mode waveguide which are connected in sequence; the middle input conical waveguide and the side input conical waveguide are symmetrically distributed about the optical axis, the first multimode waveguide and the second multimode waveguide comprise interference areas and transition areas, and the width of the transition areas is narrowed in the light propagation direction; the transmission loss of the end face coupler can be reduced, the alignment tolerance is increased, and the processing difficulty is reduced.

The utility model discloses an on-chip integrated nineteen-core five-mode fan-in and fan-out device and a detection system based on orbital angular momentum, and the device comprises eighteen bent multi-mode waveguides with doughnut-shaped sections and a straight multi-mode waveguide which is located at the center and has the same section, each bent multi-mode waveguide is composed of 24 bent single-mode waveguides, the straight multimode waveguide is composed of 24 straight single-mode waveguides. Through the waveguide configuration of a special structure, after the structured light of each core of the multi-core optical fiber is transmitted in the device, the structured light can be effectively separated in space on the basis of keeping the original OAM mode, so that the processing and analysis of a subsequent light field on a multi-mode signal are facilitated, and a hardware basis is provided for high-capacity optical communication based on orbital angular momentum.

The application belongs to the field of optoelectronic technology and particularly relates to an ultra-wideband optical directional coupler, which comprises three single-mode waveguides arranged in parallel at intervals and having the same width, contains straight waveguides and curved waveguides, and one curved waveguide is arranged between two adjacent straight waveguides; straight waveguide ports supporting edge state modes at both ends of a waveguide structure composed of the three single-mode waveguides are respectively used as a coupler input port and an output port; the curved waveguide is a modulation waveguide, and the center distance between the modulation waveguide and one of the straight waveguides adjacent to the modulation waveguide is characterized by a modulation function which changes uniformly and slowly in the propagation direction, the tangent of the function at both ends of the device is parallel to the straight waveguide, and the change relation involves parameters such as the total length of the device, the modulation amplitude of the bending in the direction perpendicular to the propagation direction, and the position of the input port end in the propagation direction. The application greatly improves the response bandwidth of the device.

The application discloses a TM mode polarizer based on a curved narrow waveguide, which comprises a single-mode input waveguide, an input end conversion waveguide, a curved narrow waveguide, an output end conversion waveguide and a single-mode output waveguide along the light transmission direction. The input light is first converted into the mode supported by the narrow waveguide by the input end conversion waveguide, then the input TE mode is leaked and the input TM mode is passed by reasonably selecting the bending radius and width of the curved narrow waveguide, and finally the TM mode supported by the single-mode waveguide is converted by the output end conversion waveguide, so that the polarizer function of filtering the TE mode and passing the TM mode is realized. The application comprises, in the direction perpendicular to the light transmission plane, an upper cladding layer, a core layer, a buried oxygen layer and a substrate in sequence. The application can realize a high-performance TM mode polarizer in a large optical bandwidth due to the wavelength-insensitive structure, and has important practical application value in the fields of on-chip optical communication, optical sensing and spectroscopy.

The application provides an optical multimode interference coupler. The optical multimode interference coupler of the application directly connects a transmission waveguide with a slit structure and a bar-shaped multimode waveguide at an interface, and based on multimode excitation principle and self-imaging principle of the multimode interference coupler, the optical signal in the bar-shaped multimode waveguide is simultaneously split and the waveguide structure is converted at the interface in the slit single-mode waveguide, without using a traditional tapered bar-slit waveguide conversion structure, so that the length of the electronic component is effectively reduced and the integration of the component is improved. The application realizes that the input optical signal can be directly and evenly divided into two slit waveguides from the bar-shaped waveguide, without using a traditional combination structure of splitting light first and then converting. The device has the advantages of small size, low loss, high bandwidth and the like.