A high-resolution on-chip integrated computational spectrometer based on disordered-slit structure

Abstract

The application provides a high-resolution on-chip integrated computing spectrometer based on a disordered slit structure, comprising an input waveguide module, a multimode scattering waveguide and an output waveguide array which are sequentially connected in the order of the light direction, the input waveguide module is provided with a slit focusing lens assembly and an electrothermal dimmer switch assembly, the multimode scattering waveguide is provided with a scattering disordered slit group, the scattering disordered slit group is composed of a plurality of parallel arranged scattering slits with the same width, random length within a set range and the same spacing, the length of the multimode scattering waveguide is greater than 10 times the width of the scattering disordered slit group, the width of the multimode scattering waveguide is greater than one or more times of the working wavelength of the high-resolution on-chip integrated computing spectrometer, and the output waveguide array is provided with a single-mode optical waveguide array composed of a plurality of single-mode optical waveguides. The application has the beneficial effects of being able to reduce the size, being able to realize precise regulation and control of the light output position by a small number of electrodes, and being able to improve the scattering disorder degree of the light wave in a limited size.

Description

Technical Field

[0001] This invention relates to the field of spectrometer technology, and more specifically to a high-resolution on-chip integrated computational spectrometer based on a disordered slit structure. Background Technology

[0002] Light is an electromagnetic wave containing rich frequency information. Spectroscopic analysis technology achieves accurate and rapid non-contact sensing and detection through emission, absorption, and scattering, offering unparalleled advantages in biochemical sensing and materials analysis. Traditional discrete-device spectrometers, due to their beam control units, spectral dispersive units, or interferometric units, inevitably suffer from large size, heavy weight, and high cost. In recent years, the continuous development of micro-nano fabrication technology has led to the emergence of novel micro-nano optoelectronic devices, resulting in rapid progress in miniaturized spectrometers that are small in size, low in cost, and portable. Existing commercial spectrometers are limited by the constraints of their operating environment, while on-chip spectrometers, as a crucial component in spectrometer miniaturization, offer advantages such as small size and greater portability, which hold the promise of solving the aforementioned challenges in spectral analysis.

[0003] Currently, most spatial spectrometers are dispersive spectrometers based on grating spectroscopy. These discrete devices are typically very large because they require a certain optical path to accumulate dispersion. The development of micro- and nano-scale technology has enabled spectrometers to be implemented on chips. To date, on-chip spectrometers can be classified into four main categories: dispersive spectrometers, filtered spectrometers, Fourier transform spectrometers, and computational reconstruction spectrometers.

[0004] Before 2000, the most common types of on-chip spectrometers were dispersive or filtered spectrometers. These two types of spectrometers relied on a one-to-one spectral-spatial mapping for dispersion, and common technical approaches included arrayed waveguide gratings, photonic crystals, and micro-ring arrays. Although this mapping method was intuitive, achieving high resolution often required a large device size.

[0005] After 2000, on-chip Fourier transform spectrometers began to appear. This type of spectrometer has a much faster scanning speed than dispersive spectrometers and requires fewer optical components, relying mainly on interferometer components, thus resulting in better signal-to-noise ratio. The size of on-chip Fourier transform spectrometers is mainly limited by the optical path difference and the number of interferometers. While the size has been improved compared to the aforementioned spectrometers, further reduction remains challenging.

[0006] Compared to the aforementioned spectrometers, computational reconstruction spectrometers are characterized by a more complex one-to-many spectral-spatial mapping. Unlike dispersive or filtered spectrometers, which directly obtain the original spectrum, computational spectrometers require complex reconstruction algorithms to decode the original spectrum, but can significantly improve space utilization and device integration. This one-to-many spectral-spatial mapping relationship can be mathematically represented as a matrix transforming spectral space into physical space. Common technical approaches include on-chip disordered scattering structures and multimode helical waveguides. However, the speckle pattern formed by the disordered scattering structure originates from multiple scattering events within the structure, leading to significant vertical loss in the spectrometer. The speckle disorder of the multimode helical waveguide structure mainly comes from evanescent coupling and mode aliasing between waveguides, requiring longer dimensions and paths to provide sufficient disorder. Furthermore, due to the fixed position of the input waveguide, both methods have relatively small bandwidths. Summary of the Invention

[0007] To address the problems in existing technologies, this invention provides a high-resolution on-chip integrated computational spectrometer based on a disordered slit structure. This spectrometer can reduce its size while achieving precise control of the light output position by controlling the heating level with a few electrodes. Furthermore, it can maximize the scattering disorder of light waves in a multimode scattering waveguide within a limited size, solving the problems in existing technologies where disordered scattering structures lead to significant vertical losses in the spectrometer, multimode spiral waveguides require long dimensions and paths to provide sufficient disorder, and the fixed position of the input waveguide results in limited bandwidth.

[0008] This invention provides a high-resolution on-chip integrated computational spectrometer based on a disordered slit structure, comprising a chip platform and an input waveguide module, a multimode scattering waveguide, and an output waveguide array disposed within the chip platform. The input waveguide module, the multimode scattering waveguide, and the output waveguide array are sequentially connected along the illumination direction. The input waveguide module contains a slit focusing lens assembly and an electrothermal dimming switch assembly that cooperate with each other. The multimode scattering waveguide contains a multi-layered group of parallel, disordered scattering slits, each consisting of multiple parallel scattering slits with uniform width and random lengths within a set range. The composition includes two scattering slits with equal spacing, a multimode scattering waveguide with a length along the illumination direction greater than 10 times the width of the scattering disorder slit group, a multimode scattering waveguide with a width greater than one or more times the operating wavelength of the high-resolution on-chip integrated computational spectrometer, an output waveguide array containing a single-mode waveguide array composed of multiple single-mode waveguides, a slit focusing lens assembly and an electrothermal dimming switch assembly capable of adjusting the position of the light wave output from the input waveguide module to the multimode scattering waveguide by heating and focusing, and a scattering disorder slit group capable of increasing the scattering disorder of the light wave passing through the multimode scattering waveguide.

[0009] The present invention is further improved in that the chip platform is a silicon-on-insulator platform, including a silicon dioxide cladding layer, a waveguide mounting silicon layer, a silicon dioxide layer and a silicon substrate layer from top to bottom. The electrothermal dimming switch assembly is disposed in the silicon dioxide cladding layer, and the slit focusing lens assembly, the multimode scattering waveguide and the output waveguide array are all disposed in the waveguide mounting silicon layer.

[0010] The present invention is further improved in that the thickness of the silicon layer on the waveguide is 220 nm.

[0011] The present invention is further improved in that the electrothermal dimming switch assembly includes a metal electrode and a serpentine thermal resistor. The metal electrode is electrically connected to the serpentine thermal resistor. The serpentine thermal resistor is laid out in a serpentine shape within the silicon dioxide layer. The serpentine thermal resistor as a whole forms two sets of matching triangular heating regions.

[0012] The present invention is further improved in that the slit focusing lens assembly includes two sets of dimming slits respectively disposed on both sides of the serpentine thermal resistor along the illumination direction. The dimming slits are generally concave on one side and are composed of multiple parallel dimming slits of the same width. The length of the dimming slits gradually decreases from both ends to the middle of the dimming slits. The two sets of dimming slits and the serpentine thermal resistor together form a concave lens.

[0013] The present invention is further improved in that the incident waveguide of the input waveguide module is a single-mode waveguide, wherein the width of the single-mode waveguide is 500nm.

[0014] The present invention is further improved in that the length of the multimode scattering waveguide is ≥10µm.

[0015] The present invention is further improved in that there are a total of 3 groups of scattering disorder slits in the multimode scattering waveguide.

[0016] The present invention is further improved in that the width of the scattering slit is 180 nm, the length of the scattering slit is selected in the range of 1 μm ≤ scattering slit length ≤ 3 μm, and the distance between the two scattering slits is 500 nm.

[0017] In a further improvement to the present invention, an adiabatic tapered waveguide is provided within the output waveguide array, and the multimode scattering waveguide is connected to the single-mode optical waveguide array through the adiabatic tapered waveguide.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows: The present invention provides a high-resolution on-chip integrated computational spectrometer based on a disordered slit structure. By arranging an input waveguide module, a multimode scattering waveguide, and an output waveguide array within the high-resolution on-chip integrated computational spectrometer, and including a slit focusing lens assembly and an electrothermal dimming switch assembly within the input waveguide module, the slit focusing lens assembly and the electrothermal dimming switch assembly can adjust the position of the light wave output from the input waveguide module to the multimode scattering waveguide through heating and focusing. The disordered slit array can improve the scattering disorder of the light wave passing through the multimode scattering waveguide. This allows for precise adjustment of the light output position by controlling the heating degree with a few electrodes while reducing the size of the high-resolution on-chip integrated computational spectrometer. The control method, by adjusting the light output position through electrodes while ensuring resolution and reducing losses, can also broaden the working bandwidth of the high-resolution on-chip integrated computational spectrometer. Moreover, the scattering disorder slit group set in the multimode scattering waveguide can maximize the scattering disorder of light waves in the multimode scattering waveguide within a limited size, and can also significantly reduce the size of the high-resolution on-chip integrated computational spectrometer. The output waveguide array contains a single-mode optical waveguide array composed of multiple single-mode optical waveguides, which can collect light intensity at different positions. This solves the problems in the prior art where disordered scattering structures lead to large losses in the vertical direction of the spectrometer, multimode spiral waveguides require long dimensions and paths to provide sufficient disorder, and the fixed position of the input waveguide results in small bandwidth. Attached Figure Description

[0019] To more clearly illustrate the solutions in this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0020] Figure 1 This is a top view of the high-resolution on-chip integrated computational spectrometer based on a disordered slit structure according to the present invention;

[0021] Figure 2 This is a three-dimensional view of the high-resolution on-chip integrated computational spectrometer based on the disordered slit structure of the present invention.

[0022] Figure 3 This is a thermal field distribution diagram of the electrothermal dimming switch component area of ​​the present invention;

[0023] Figure 4 This is a graph showing the relationship between the transmittance, phase change, length, and width of the scattering slit of the present invention.

[0024] Figure 5 This is a simulated optical field distribution diagram of the multimode scattering waveguide region of the present invention;

[0025] Figure 6 This is a simulated speckle pattern output by a high-resolution on-chip integrated computational spectrometer based on a disordered slit structure, according to the present invention.

[0026] Figure 7 The spectral correlation function curve of the high-resolution on-chip integrated computational spectrometer based on the disordered slit structure of this invention is shown below.

[0027] Figure 8 This is a reconstruction of some structural spectra by the high-resolution on-chip integrated computational spectrometer based on the disordered slit structure of this invention.

[0028] The figure shows the spectral intensity fingerprint of the input waveguide module, 11 slit focusing lens assembly, 12 electrothermal dimming switch assembly, 2 multimode scattering waveguide, 21 scattering disordered slit group, 3 output waveguide array, and 4 output waveguide array. Detailed Implementation

[0029] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used herein in the specification of the application is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having” and any variations thereof in the specification, claims and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0030] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0031] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings.

[0032] like Figure 1-8As shown, the present invention provides a high-resolution on-chip integrated computational spectrometer based on a disordered slit structure, comprising a chip platform and an input waveguide module 1, a multimode scattering waveguide 2, and an output waveguide array 3 disposed within the chip platform. The input waveguide module 1, the multimode scattering waveguide 2, and the output waveguide array 3 are sequentially connected along the illumination direction. The input waveguide module 1 contains a slit focusing lens assembly 11 and an electrothermal dimming switch assembly 12 that cooperate with each other. The multimode scattering waveguide 2 contains a multi-layered, parallel, disordered scattering slit group 21, which consists of multiple parallel scattering slits with the same width and random lengths within a set range. The spacing between two scattering slits is the same. The length of the multimode scattering waveguide 2 along the illumination direction is greater than 10 times the width of the disordered scattering slit group 21, and the width of the multimode scattering waveguide 2 is greater than one or more times the operating wavelength of the high-resolution on-chip integrated computational spectrometer. The output waveguide array 3 contains a single-mode optical waveguide array composed of multiple single-mode optical waveguides. In this embodiment, the slit focusing lens assembly and the electrothermal dimming switch assembly can adjust the position of the light wave output from the input waveguide module to the multimode scattering waveguide by heating and focusing. The scattering disorder slit group can improve the scattering disorder of the light wave passing through the multimode scattering waveguide. It can reduce the size of the high-resolution on-chip integrated computational spectrometer while achieving precise control of the light output position by controlling the heating degree with a few electrodes. While ensuring resolution and reducing loss, the light output position can also be controlled by electrodes to broaden the working bandwidth of the high-resolution on-chip integrated computational spectrometer. Moreover, the scattering disorder slit group set in the multimode scattering waveguide can maximize the scattering disorder of the light wave in the multimode scattering waveguide within a limited size, and can also significantly reduce the size of the high-resolution on-chip integrated computational spectrometer. The output waveguide array is equipped with a single-mode optical waveguide array composed of multiple single-mode optical waveguides, which can collect the light intensity at different positions.

[0033] In this embodiment, a multimode scattering waveguide with localized thermal modulation replaces the traditional Mach-Zehnder cascade structure to achieve the optical switching function. The serpentine distribution of the heating wires in the electrothermal optical switching component ensures that the local refractive index change meets requirements, while maintaining a smaller size than the Mach-Zehnder cascade optical switch array, resulting in a more integrated overall device. The width of the multimode scattering waveguide is greater than one or more times the operating wavelength of the high-resolution on-chip integrated computational spectrometer, ensuring a sufficient number of modes. Superimposing multiple layers of disordered scattering slits on this basis results in more complex mode aliasing, ultimately improving the disorder of the output speckle. The scattering slits inside the multimode scattering waveguide are only disordered in length, thus creating a disordered refractive index gradient layer within the multimode scattering waveguide to improve... The disorder and path of light scattering are controlled, and the width of all scattering slits is kept at a fixed value with high transmission to ensure high transmittance. In this embodiment, the width of the scattering slits is 180 nm. The wider the multimode scattering waveguide, the more conducive it is to the coexistence of multiple modes, thereby forming speckle with higher disorder and improving the resolution of the spectrometer. However, in order to reduce the effective size, combined with the output position of the electrothermal dimming switch component, a three-layer scattering disorder slit group is designed in the scattering region inside the multimode scattering waveguide. This improves the disorder of the final speckle without increasing the size. The output end of the multimode scattering waveguide is connected to the single-mode optical waveguide array by an adiabatic tapered waveguide. After outputting to the grating coupler, the light intensity distribution is detected by optical fiber as a spectral fingerprint. The adiabatic tapered waveguide, i.e., the taper waveguide, can reduce reflection loss.

[0034] like Figure 2 As shown, the chip platform is a silicon-on-insulator platform, including a silicon dioxide cladding layer, a waveguide mounting silicon layer, a silicon dioxide layer and a silicon substrate layer from top to bottom. The electrothermal dimming switch assembly 12 is disposed within the silicon dioxide cladding layer. The slit focusing lens assembly 11, the multimode scattering waveguide 2 and the output waveguide array 3 are all disposed within the waveguide mounting silicon layer, wherein the thickness of the waveguide mounting silicon layer is 220nm.

[0035] An optical waveguide is a dielectric device that guides the propagation of light waves; it is also called a dielectric waveguide. There are two main types of optical waveguides: one is integrated optical waveguides, including planar (thin-film) dielectric waveguides and strip dielectric waveguides, which are usually part of optoelectronic integrated devices (or systems), hence the name integrated optical waveguides; the other is cylindrical optical waveguides, commonly called optical fibers (see optical fibers). An optical waveguide is a guiding structure for transmitting optical frequency electromagnetic waves, constructed from an optically transparent medium (such as quartz glass). The transmission principle of an optical waveguide differs from that of a closed metal waveguide. At the interface between media with different refractive indices, the total internal reflection phenomenon of electromagnetic waves confines the light wave to a limited area within and around the waveguide. In this embodiment, a high-resolution on-chip integrated computational spectrometer is realized using an optical waveguide.

[0036] like Figure 1-3 As shown, the input waveguide module 1 has a single-mode waveguide with a width of 500 nm. The electrothermal dimming switch assembly 12 includes a metal electrode and a serpentine thermal resistor. The metal electrode is electrically connected to the serpentine thermal resistor, which is laid out in a serpentine pattern within the silicon dioxide cladding layer. The serpentine thermal resistor forms two sets of matching triangular heating regions. The slit focusing lens assembly 11 includes two sets of dimming slits arranged on both sides of the serpentine thermal resistor along the illumination direction. The dimming slits are concave on one side and consist of multiple parallel dimming slits of uniform width. The length of the dimming slits gradually decreases from both ends to the middle. The two sets of dimming slits and the serpentine thermal resistor together form a concave lens. In this embodiment, the 500 nm width of the single-mode waveguide ensures a uniform light field distribution when the 1550 nm single-mode incident light enters the taper region, and the optical path difference from the incident port to the slit focusing lens assembly region is fixed. The purpose of the double-slit focusing lens assembly is to transform the input single-mode divergent light wave vector into a wave vector along the waveguide propagation direction. In subsequent control processes, localized thermal tuning ensures relative focusing of the output light. Different wavelengths are focused to different positions after passing through the thermally tuned area due to local refractive index differences. The uniform, triangular-like heating region deflects the fundamental mode after its overall transmission and focuses it at the input end of the multimode scattering waveguide region via the slit focusing lens assembly. Adjusting the heating voltage adjusts the focusing angle of the light transmission, thus changing the exit position.

[0037] like Figure 1-3 As shown, the length of the multimode scattering waveguide 2 is ≥10 μm. There are three groups of disordered scattering slits 21 within the multimode scattering waveguide 2. The width of each slit is 180 nm, and the length of each slit is selected within the range of 1 μm ≤ slit length ≤ 3 μm. The spacing between two slits is 500 nm. In this embodiment, the width of the multimode scattering waveguide region is ≥10 μm to ensure the diversity of excited modes. The width of the slits is 180 nm, and the spacing between two slits is 500 nm. Only the disorder in the length direction of the slits is adjusted to ensure disordered scattering in the multimode waveguide while maintaining high transmittance. The width of the slits can be adjusted within the 2π phase range. To ensure high transmission efficiency and compact overall device size, the selected slit length is between 1 and 3 μm, based on the following criteria: Figure 4As shown in the figure, when the width of the scattering slit is fixed at 180 nm, the overall transmittance is relatively high. By adjusting the length of the scattering slit, phase disorder modulation in the multimode scattering waveguide can be achieved, thereby obtaining a spectral fingerprint with low correlation. In addition, the overall length of the multimode scattering waveguide region is much larger than the width of the disordered scattering slit group. Therefore, the overall wave vector direction of the transmitted light is still along the propagation direction of the waveguide, and its loss is reduced compared to the disordered scattering structure.

[0038] like Figure 1-3 As shown, the output waveguide array 3 is also equipped with an adiabatic conical waveguide. The multimode scattering waveguide 2 is connected to the single-mode optical waveguide array through the adiabatic conical waveguide, which can reduce the mode loss of the final output.

[0039] like Figure 5 The image shows the simulated optical field distribution within the multimode scattering waveguide and the corresponding output speckle pattern, obtained by exciting the multimode scattering waveguide at different input positions in the 1550nm band in TEO mode according to the present invention. Figure 5 As shown, when light waves enter the multimode scattering waveguide region from the input waveguide module, they first excite multiple modes. During propagation, disordered scattering occurs at the scattering slits, generating a series of wavelength-dependent speckles, thus obtaining the specificity of the output. Based on this, we can analyze and calculate the original input spectrum using reconstruction algorithms such as compressed sensing. Furthermore, when light waves enter the multimode scattering waveguide region from the input waveguide module through different locations, they excite different fields and modes. This leads to different final speckles produced along the same path, increasing the spectral bandwidth and improving the applicability of the spectrometer.

[0040] like Figure 6 As shown, this figure simulates the power speckle distribution at the output end of a multimode scattering waveguide region formed after the excited light field enters the input waveguide module through nine different locations and is scattered and propagates within the multimode scattering waveguide with a disordered scattering slit group. With a basis function of 1, this can be directly considered as the transmission matrix of the spectrometer. The horizontal axis represents the wavelength channel, and the vertical axis represents the detection channel; the color intensity represents the optical power. This speckle pattern is directly related to the performance of the spectrometer. Based on the spectral correlation function... The spectral correlation function curve of the spectrometer can be plotted, such as... Figure 7 As shown.

[0041] like Figure 7 As shown, C(δλ) represents the spectral correlation, δλ represents the wavelength interval, and C i Represents the detector channel, I(λ, C) i () indicates that the wavelength channel is λ and the detection channel is C. i The power level at that time, <…> λ Take the sign of the average wavelength, <…> iThe average sign of the detection channels is taken. The resolution of the spectrometer can be estimated by the half-width at half-maximum (WHM) of the spectral correlation function, which represents the minimum wavelength separation required to reduce the correlation by half. As shown in the figure, the theoretical prediction of the spectral resolution of this high-resolution on-chip integrated computational spectrometer based on the disordered slit structure is 6.5 nm.

[0042] like Figure 8 As shown in the figure, this graph illustrates the spectrometer's recovery of a preset spectral signal. The detected output signal is used as a unique fingerprint, and a compressed sensing algorithm is employed to reconstruct the input spectral signal. The results demonstrate that the spectrometer can reconstruct and recover both discrete and continuous spectra, and can accurately recover spectral information at different wavelengths and intensities. Its operating bandwidth covers 200 nm, from 1450 nm to 1650 nm.

[0043] As can be seen from the above, this invention provides a high-resolution on-chip integrated computational spectrometer based on a disordered slit structure. By incorporating a mutually cooperating input waveguide module, multimode scattering waveguide, and output waveguide array within the high-resolution on-chip integrated computational spectrometer, and including a slit focusing lens assembly and an electrothermal dimming switch assembly within the input waveguide module, the slit focusing lens assembly and the electrothermal dimming switch assembly can adjust the position of the light wave output from the input waveguide module to the multimode scattering waveguide through heating and focusing. The disordered slit array can increase the scattering disorder of the light wave passing through the multimode scattering waveguide. This allows for precise control of the light output position by controlling the heating degree with a few electrodes while reducing the size of the high-resolution on-chip integrated computational spectrometer, ensuring resolution. Based on improving efficiency and reducing losses, the optical output position can be adjusted by electrodes, which can also broaden the working bandwidth of the high-resolution on-chip integrated computational spectrometer. Moreover, the scattering disorder slit group set in the multimode scattering waveguide can maximize the scattering disorder of light waves in the multimode scattering waveguide within a limited size, and can also significantly reduce the size of the high-resolution on-chip integrated computational spectrometer. The output waveguide array contains a single-mode optical waveguide array composed of multiple single-mode optical waveguides, which can collect light intensity at different positions. This solves the problems in the prior art where disordered scattering structure leads to large losses in the vertical direction of the spectrometer, multimode spiral waveguides require long size and path to provide sufficient disorder, and the fixed position of the input waveguide leads to small bandwidth.

[0044] The specific embodiments described above are preferred embodiments of the present invention and are not intended to limit the specific scope of the present invention. The scope of the present invention includes, but is not limited to, these specific embodiments. All equivalent changes made in accordance with the present invention are within the protection scope of the present invention.

Claims

1. A high-resolution on-chip integrated computational spectrometer based on a disordered slit structure, characterized in that: The system includes a chip platform and an input waveguide module, a multimode scattering waveguide, and an output waveguide array disposed within the chip platform. The input waveguide module, the multimode scattering waveguide, and the output waveguide array are sequentially connected along the illumination direction. The input waveguide module contains a slit focusing lens assembly and an electrothermal dimming switch assembly that cooperate with each other. The multimode scattering waveguide contains multiple parallel groups of randomly arranged scattering slits. Each group of randomly arranged scattering slits consists of multiple parallel slits with the same width and random lengths within a set range. The spacing between two scattering slits is... Similarly, the length of the multimode scattering waveguide along the illumination direction is greater than 10 times the width of the scattering disorder slit group, and the width of the multimode scattering waveguide is greater than one or more times the operating wavelength of the high-resolution on-chip integrated computational spectrometer. The output waveguide array contains a single-mode optical waveguide array composed of multiple single-mode optical waveguides. The slit focusing lens assembly and the electrothermal dimming switch assembly can adjust the position of the light wave output from the input waveguide module to the multimode scattering waveguide by heating and focusing. The scattering disorder slit group can improve the scattering disorder of the light wave passing through the multimode scattering waveguide.

2. The high-resolution on-chip integrated computational spectrometer based on a disordered slit structure according to claim 1, characterized in that: The chip platform is a silicon-on-insulator platform, comprising, from top to bottom, a silicon dioxide cladding layer, a waveguide mounting silicon layer, a silicon dioxide layer, and a silicon substrate layer. The electrothermal dimming switch assembly is disposed within the silicon dioxide cladding layer, and the slit focusing lens assembly, the multimode scattering waveguide, and the output waveguide array are all disposed within the waveguide mounting silicon layer.

3. The high-resolution on-chip integrated computational spectrometer based on a disordered slit structure according to claim 2, characterized in that: The thickness of the silicon layer on the waveguide is 220 nm.

4. The high-resolution on-chip integrated computational spectrometer based on a disordered slit structure according to claim 2 or 3, characterized in that: The electrothermal dimming switch assembly includes a metal electrode and a serpentine thermal resistor. The metal electrode is electrically connected to the serpentine thermal resistor, which is laid out in a serpentine shape within the silicon dioxide coating layer. The serpentine thermal resistor as a whole forms two sets of matching triangular heating regions.

5. The high-resolution on-chip integrated computational spectrometer based on a disordered slit structure according to claim 4, characterized in that: The slit focusing lens assembly includes two sets of dimming slits respectively disposed on both sides of the serpentine thermal resistor along the illumination direction. The dimming slits are generally concave on one side and are composed of multiple parallel dimming slits of the same width. The length of the dimming slits gradually decreases from both ends to the middle of the dimming slits. The two sets of dimming slits and the serpentine thermal resistor together form a concave lens shape.

6. The high-resolution on-chip integrated computational spectrometer based on a disordered slit structure according to claim 5, characterized in that: The input waveguide module has an incident waveguide that is a single-mode waveguide with a width of 500 nm.

7. The high-resolution on-chip integrated computational spectrometer based on a disordered slit structure according to claim 6, characterized in that: The length of the multimode scattering waveguide is ≥10µm.

8. The high-resolution on-chip integrated computational spectrometer based on a disordered slit structure according to claim 7, characterized in that: There are a total of 3 groups of scattering disordered slits in the multimode scattering waveguide.

9. The high-resolution on-chip integrated computational spectrometer based on a disordered slit structure according to claim 8, characterized in that: The width of the scattering slit is 180 nm, the length of the scattering slit is selected within the range of 1 μm ≤ scattering slit length ≤ 3 μm, and the distance between the two scattering slits is 500 nm.

10. The high-resolution on-chip integrated computational spectrometer based on a disordered slit structure according to claim 9, characterized in that: The output waveguide array is further provided with an adiabatic tapered waveguide, and the multimode scattering waveguide is connected to the single-mode optical waveguide array through the adiabatic tapered waveguide.

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