CN112857410A - Digital distributed interference imaging system - Google Patents
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Abstract
The application discloses imaging system is interfered to digital distributing type includes: the device comprises a reference light unit, an object light information acquisition unit and an image reconstruction unit; the object light information acquisition unit comprises a micro-mirror layer, a waveguide layer and a digitization layer; the reference light unit is used for emitting reference light; the micro-mirror layer is used for discretely collecting object light of a target object; the waveguide layer comprises a plurality of interference units, and the reference light and the object light interfere in the interference units; the digitization layer is used for converting an interference result of the reference light and the object light output by the interference unit into object light information digitized by a target object; the image reconstruction unit is used for reconstructing an image of the target object according to the digitalized object light information. Compared with the prior art, the method and the device have the advantages that the limitation of a main flow process on the processing of a large-size chip is avoided, and the equivalent caliber and the resolution of an imaging system are greatly expanded; the optical transmission loss of an object is reduced, and the imaging time is shortened; meanwhile, any two local object lights can be paired, and the utilization rate of object light signals is improved.
Description
Technical Field
The application belongs to the technical field of micro-nano optoelectronic devices and integration, and particularly relates to a digital distributed interference imaging system.
Background
The basic design principle of conventional optical telescopes is still based on the optical catadioptric principle, whereby the object of view is magnified by a lens stack. Limited by the traditional optical imaging principle, the catadioptric optical telescope is required to have better observation effect and only can make the main lens larger and heavier. The interference imaging system is composed of a series of tiny photoelectric lens units (micro mirrors for short) in an array on a plane, and utilizes the phase information of local object light to perform interference imaging, such as an optical interference thin-film imaging system.
The interference imaging system performs inverse Fourier transform on the discrete light field interference information based on the Van Satt-Zernike theorem to obtain a reconstructed image. The photonic integrated chip is used for replacing the traditional lens group, the volume and the weight are greatly reduced, and the photonic integrated chip is gradually developed into an advanced photoelectric imaging technology. The system obtains abundant high-frequency information by increasing the length of the base line, and then improves the resolution of the image. According to the design principle of an interference imaging system, the key point of obtaining a high-quality image is to obtain quasi-continuous and complete information of an object image in a frequency domain space: the low frequency part describes the object contour, while the high frequency part corresponds to the image detail. In practice, every two micromirrors on the photonic integrated circuit board are paired, the distance between each pair of micromirrors defines an interference baseline, the length of the interference baseline is in direct proportion to the size of spatial frequency, the longer the baseline is, the larger the corresponding spatial frequency is, the larger the frequency domain range which can be covered is, the higher the resolution is, and the clearer the image is.
The existing interference imaging system design can only be realized by increasing the size of a single photon integrated chip when the length of an interference baseline is increased: the method is limited by a photoetching exposure process, the current mainstream step-and-scan photoetching machine can only realize single exposure of a square centimeter level while ensuring the high-precision preparation of the optical waveguide with the width of hundreds of nanometers, and the preparation of the large-size high-precision interference baseline optical waveguide is a huge technical challenge. Although electron beam direct-writing exposure splicing or chip bridging may hopefully complete large-size preparation, the introduced splicing error and the longer propagation distance thereof greatly increase the transmission loss of object light in the waveguide, reduce the signal-to-noise ratio, increase the detection difficulty, and are not beneficial to the realization of a high-quality imaging chip. In the application of remote detection, the longest interference baseline may need to be as long as dozens of centimeters to meters, how to obtain a large-size high-quality low-loss chip in the existing process capability range, meet the requirement of long baseline interference and ensure high-efficiency low-cost processing is the key of sustainable development of a high-resolution interference imaging system.
Disclosure of Invention
In view of this, the embodiment of the present application provides a digital distributed interference imaging system, which is suitable for the current mainstream process capability, meets the requirement of high-resolution imaging on a long interference baseline, and can significantly reduce the object light transmission loss of the interference imaging system, and improve the signal-to-noise ratio and the imaging quality.
The embodiment of the application provides a digital distributed interference imaging system, includes:
the device comprises a reference light unit, an object light information acquisition unit and an image reconstruction unit; the object light information acquisition unit comprises a micro-mirror layer, a waveguide layer and a digitization layer;
the reference light unit is used for emitting coherent reference light;
the micro-mirror layer comprises a plurality of micro-mirrors, the micro-mirrors form a plurality of micro-mirror arrays, and the micro-mirror arrays are distributed and used for discretely collecting object light of a target object;
the waveguide layer comprises a plurality of interference units, the interference units form a plurality of interference unit arrays, the interference unit arrays are distributed and are arranged in a one-to-one correspondence mode with the micromirrors, the interference units are connected with the reference light unit through waveguides, and the reference light and the object light are interfered in the interference units;
the digital layer is used for converting an interference result of the reference light and the object light output by the interference unit into an analog electric signal, amplifying and filtering the analog electric signal, performing analog-to-digital conversion to finally generate digital information corresponding to the interference result, and demodulating the object light information digitized by the target object from the digital information by utilizing the known information of the reference light;
the image reconstruction unit is used for reconstructing an image of a target object according to a preset interference baseline design scheme, the position information of each micromirror and object light information corresponding to the discretization object light collected by the micromirror; the interference baseline design scheme comprises interference baseline vectors formed by pairing all two micromirrors.
In some embodiments of the present application, the waveguide layer comprises a plurality of interference unit arrays, each interference unit array comprising a plurality of interference units, each interference unit array being connected to the reference light unit by a waveguide or an optical fiber, respectively.
In some embodiments of the present application, the interference unit includes a vertical coupler, a first phase shifter, a second phase shifter, and an interference member;
the vertical coupler is connected with the interference component through a waveguide, the first phase shifter is arranged between the reference light unit and the interference component, and the second phase shifter is arranged in the interference component;
the object light is collected by the micro mirror and enters the interference part through the vertical coupler, the reference light enters the interference part after passing through the first phase shifter to unify the phase, the phase is adjusted to a preset phase through the second phase shifter, and the reference light after adjusting the phase interferes with the object light in the interference part.
In some embodiments of the present application, the digitizing layer comprises a plurality of light detecting components, analog electrical signal processing circuitry, and analog/digital conversion circuitry; the plurality of optical detection components are distributed and are arranged in one-to-one correspondence with the plurality of interference units;
the optical detection component is used for detecting the interference result in the corresponding interference unit and converting the interference result into an analog electric signal;
the analog electric signal processing circuit is used for amplifying and filtering the analog electric signals output by each optical detection component;
and the analog/digital conversion circuit converts the processed analog electric signal into a digital signal to obtain digital information corresponding to the interference result.
In some embodiments of the present application, the reference light unit is a coherent light source, and the coherent light source is a pulsed laser, an optical comb, or a continuous laser that emits light intermittently.
In some embodiments of the present application, the object light information includes amplitude information and phase information.
The digital distributed interference imaging system comprises a reference light unit, an object light information acquisition unit and an image reconstruction unit; the object light information acquisition unit comprises a micro-mirror layer, a waveguide layer and a digitization layer; the reference light unit is used for emitting reference light; the micro-mirror layer is used for discretely collecting object light of a target object; the waveguide layer comprises a plurality of interference units, the interference units are distributed and are arranged in a one-to-one correspondence with the micromirrors, and the reference light and the object light interfere in the interference units; the digitization layer is used for converting an interference result of the reference light and the object light output by the interference unit into object light information digitized by a target object; the image reconstruction unit is used for reconstructing an image of the target object according to the digitalized object light information. Compared with the prior art, the digital distributed interference imaging system has the advantages that each local object light is digitized, any two local object lights can be paired, the object light signals can be repeatedly used for many times, and the frequency domain space full coverage is realized; meanwhile, the pairwise pairing interference process of the digital object light is replaced by microchip operation, so that the transmission loss of the object light is reduced, a strong object light signal is ensured, and a clear object image is reconstructed; in addition, the interference unit array is distributed and arranged, and the limitation of the existing process on the chip size is avoided.
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Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the application. Also, like reference numerals are used to refer to like parts throughout the drawings. In the drawings:
FIG. 1 is a schematic diagram of a digitally distributed interferometric imaging system according to an embodiment of the present application;
fig. 2 is a schematic structural diagram of an object light information collecting unit according to an embodiment of the present application;
FIG. 3 is a schematic diagram of an interference baseline of a single array of interference units according to an embodiment of the present application;
FIG. 4 is a schematic diagram of an interference baseline of a distributed array of interference units according to an embodiment of the present application;
FIG. 5 is a schematic diagram of an interference unit and its array according to an embodiment of the present application;
fig. 6 is a schematic diagram illustrating measurement of amplitude and phase of object light based on the principle of interference according to an embodiment of the present application.
The implementation, functional features and advantages of the objectives of the present application will be further explained with reference to the accompanying drawings.
Detailed Description
The technical solutions in the embodiments of the present application will be described clearly and completely with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.
It should be noted that all the directional indications (such as up, down, left, right, front, and rear … …) in the embodiment of the present application are only used to explain the relative position relationship between the components, the movement situation, and the like in a specific posture (as shown in the drawing), and if the specific posture is changed, the directional indication is changed accordingly.
In addition, descriptions in this application as to "first", "second", etc. are for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicit to the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present application, "plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.
In this application, unless expressly stated or limited otherwise, the terms "connected," "secured," and the like are to be construed broadly, and for example, "secured" may be a fixed connection, a removable connection, or an integral part; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as appropriate.
In addition, technical solutions between the various embodiments of the present application may be combined with each other, but it must be based on the realization of the technical solutions by a person skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination of technical solutions should be considered to be absent and not within the protection scope of the present application.
Fig. 1 is a schematic diagram of a digital distributed interference imaging system provided in an embodiment of the present application, and as shown in fig. 1, the digital distributed interference imaging system 10 includes: a reference light unit 100, an object light information acquisition unit 200, and an image reconstruction unit 300;
a reference light unit 100 for emitting reference light; according to some embodiments of the present application, the reference light unit 100 may be a coherent light source, and the coherent light source may be a pulsed laser, an optical comb, or a continuous laser that emits light at intervals, where the continuous laser that emits light at intervals is different from the pulsed laser, and the interval duration of light emission at intervals may be set according to actual needs.
Fig. 2 is a schematic structural diagram of the object light information collecting unit, and as shown in fig. 2, the object light information collecting unit 200 includes a micromirror layer 210, a waveguide layer 220, and a digitizing layer 230, which are sequentially stacked. In practical applications, the object light information collecting unit 200 can be fabricated in a chip.
The micro-mirror layer 210 is used for collecting object light emitted by a target object, and the waveguide layer 220 and the digitizing layer 230 are used for converting the interference result of the object light and the reference light into digitized object light information.
Specifically, the micromirror layer 210 includes a plurality of micromirrors arranged in an array for discretely collecting object light emitted from a target object; the micromirror can be a conventional optical lens, or a thin film micromirror composed of artificial nanostructures. Conventional optical lenses require the design of specialized lens barrels and the use of precision alignment methods. The thin film micromirror can be directly fabricated above the vertical coupler by precise interlayer alignment and overlay techniques.
The waveguide layer 220 includes a plurality of interference units, the plurality of interference units are arranged in an array and are arranged in one-to-one correspondence with the plurality of micromirrors, the plurality of interference units are all connected (coupled) with the reference light unit through waveguides, and the reference light and the object light interfere in the interference units; the interference unit arrays are distributed, and interference baselines are gradually enlarged, so that the aperture of the imaging system is increased and the resolution is improved. The distributed arrangement may be an array arrangement or a non-array arrangement.
As for the interference baseline design scheme of the single interference unit array, as shown in fig. 3 and 4, the waveguide layer 220 includes a plurality of interference units 221, the interference units 221 are arranged in an array and are arranged in one-to-one correspondence with the micromirrors, the interference units 221 are coupled and connected with the reference light unit 100 through waveguides, and the reference light and the local object light interfere in the interference units;
fig. 3 is a schematic diagram of an interference baseline of a single interference unit array provided in the present application, in which a plurality of interference units 221 are arranged in an array in the x and y directions, a11 in the upper left corner represents the 1 st interference unit in the 1 st row, and a47 in the lower right corner represents the 7 th interference unit in the 4 th row. It can be seen that the base line formed by the micromirror pitches corresponding to a11 and a47 is the longest interference base line.
It is worth mentioning that in order to interface with mainstream chip manufacturing processes (such as scanning step projection exposure), the size of a single chip (single interference unit array) can be set according to the maximum area covered by a single exposure, i.e. x is 25mm, and y is 32mm (as shown in fig. 3). If the diameter of the micromirrors is 1mm and the micromirrors are densely arranged on a single chip, 25 micromirrors can be placed in the x-direction and 32 micromirrors can be placed in the y-direction. The shortest interference baseline is the distance B between two adjacent micromirrorsmin1mm, the longest interference baseline is determined by the micromirror pitch between the upper left corner and the lower right corner
For the distributed interference unit array interference baseline design scheme, specifically, the waveguide layer 220 may include a plurality of interference arrays 222, each interference array 222 includes a plurality of interference units 221, each interference array 222 is connected to the reference light unit 100 through an optical fiber, the interference units inside the interference arrays are connected through waveguides, and the interference arrays are connected to the optical fiber light-emitting ends of the reference light.
Fig. 4 is a schematic diagram illustrating an interference baseline of a set of distributed interference unit arrays provided in the present application, as shown in fig. 4, all interference units are divided into a plurality of arrays, the interference arrays are independent of each other, and the interference units in each array are connected to the reference light unit 100 through a waveguide. Therefore, if one interference array is damaged, the other interference arrays are not influenced, and the interference arrays can be expanded.
It is worth mentioning that the single chip size is limited by the current photolithography process. A plurality of chips may be arranged to form a distributed arrangement, and the same reference light is used to effectively extend the length of the interference baseline (the longest interference baseline is marked by a black arrow in the diagonal direction in fig. 4). In addition, the application can also enhance the safety of the system, and if a certain chip is damaged, other chips are not interfered. By modifying the micromirror pairing scheme, a high quality object image will still be obtained. Although fig. 4 only shows 12 chips in three rows and four columns, the number of chips in the x and y directions can be extended infinitely to meet the requirements of ultra-large aperture, ultra-long baseline and ultra-high resolution. In addition, the chips can be arranged according to the actual requirements in the directions other than the x and y directions.
Fig. 5 is a schematic diagram illustrating a structure of an interference unit and an array thereof according to the present application, and as shown in fig. 5, the interference unit 221 includes a vertical coupler 2211, a first phase shifter 2212, a second phase shifter 2214 and an interference component 2213; the interference units are periodically arranged in the x and y directions to form an interference array;
the vertical coupler 2211 is connected to the interference part 2213 by a waveguide, the phase shifter 2212 is disposed between the reference light unit 100 and the interference part 2213 by a waveguide connection, and the second phase shifter 2214 is disposed in the interference part 2213, as shown in fig. 6;
specifically, as shown in fig. 5, object light emitted from the target object is collected by the micromirror and enters the interference section 2213 through the vertical coupler 2211, reference light enters the interference section 2213 after being phase-unified by the first phase shifter 2212, the phase is adjusted to a predetermined phase (e.g., 90 ° in fig. 6) by the second phase shifter 2214, and the phase-adjusted reference light and the object light interfere in the interference section 2213.
And the digitizing layer 230 is configured to convert an interference result of the reference light and the object light output by the interference unit into an analog electrical signal, amplify and filter the analog electrical signal, perform analog-to-digital conversion, and finally generate digitized information corresponding to the interference result, and demodulate the object light information digitized by the target object from the digitized information by using the known information of the reference light.
Specifically, the digitizing layer 230 converts the interference result of each interference unit into an electrical analog signal through the optical detection element for representing the local object light information represented by each micromirror, then amplifies and filters the analog electrical signal, performs analog-to-digital conversion to obtain the digitized information of the interference signal, and finally obtains the digitized information of each local object light by using the known reference light.
The process of obtaining the object light information is illustrated as follows:
first, local object light of a target object is collected by a micromirror and enters a waveguide through a vertical coupler. The laser light is used as reference light to interfere with each beam of object light (see fig. 6 for a specific interference process), the interference result is converted into an analog electrical signal by a light detector, and the analog signal is amplified and filtered and then subjected to a/D (analog-to-digital) conversion (not shown), so that the amplitude and phase information of the interference result is digitized. Further, the known reference light is utilized to obtain the digital information of each local object light. In order to reduce the interference operation, the reference light is adjusted and unified in phase by a phase shifter before the operation.
Fig. 6 is a schematic diagram illustrating measurement of amplitude and phase of object light based on the principle of interference. As shown in FIG. 6, the reference beam R is divided into two beams, one of which has a phase increased by 90 degrees and is then respectively associated with the unknown objectThe light S interferes. The interference results are output by the four waveguides and detected by the four light detectors A, B, C and D, and the detection results of the four light detectors can be expressed by equations (1) - (4). A and B form a detection signal output by a balanced detector: i, C and D form another balance detector output detection signal: and Q. The amplitude E of the unknown object light S can be obtained by operating the equations (1) to (8) simultaneouslySAnd phase
The light detector is capable of detecting the output signals I and Q,
the phase of the reference light is unified to zero by means of a phase shifter before the measurement, i.e.
ERIs known, then
Thereby obtaining an included phase
Sum amplitude ESThe object light information of (1).
It is worth mentioning that the short coherence time of the object light requires the pulsed coherent light source as the reference light to interfere with each other. The use of pulsed laser light also brings the additional advantage that time-varying digitised optical information can be obtained. Interference information in the single pulse time is subjected to analog-to-digital conversion by a digitization layer to obtain digitized interference information, and the digitized interference information is stored in a cache layer of a microchip (image reconstruction unit). The microchip performs mathematical operation to obtain the digitalized optical information of the time period. And carrying out pairwise pairing and interference operation on the digital object light information to obtain a frequency domain space image, and then carrying out inverse Fourier transform to construct an object image of the time period. And after the next pulse laser arrives, a new round of interference, analog-to-digital conversion, calculation and image inversion is carried out, so that an image which changes along with time is obtained.
The image reconstruction unit 300 is configured to reconstruct an image of the target object according to a preset interference baseline design scheme, position information of each micromirror, and object light information corresponding to the discretized object light collected by the micromirror; the interference baseline design includes the length and direction of the interference baseline (i.e., interference baseline vector) for all pairwise micromirror pairings. The image reconstruction unit 300 may be a dedicated microprocessor chip. The length and direction of the interference base line of the micromirror pair can be determined according to the position information of the micromirror.
Specifically, the image reconstruction unit 300 determines each target micromirror pair according to a preset interference baseline design scheme and position information of each micromirror, the target micromirror pairs interfere with each other two by two to obtain position, intensity and phase information of frequency domain spatial frequency points, a frequency domain space of a target object is constructed, and a real space image of the target object is reconstructed through inverse fourier transform.
In this embodiment, the image reconstruction unit 300 freely designs an interference baseline formed by two local object optical digitized information by using the advantage that the number of times of using the digitized information is not limited, constructs a frequency domain space covered to the maximum extent, and reconstructs an image of the target object through an inverse fourier transform operation.
For example, as shown in fig. 3 and 4, taking the object light information of a certain interference unit as a reference zero point (e.g., a11 in fig. 3), the image reconstruction unit pairs the object light information of any other interference unit with the reference zero point object light information in pairs to perform interference calculation. Frequency domain spatial information can be obtained by the Van Satt-Zernike theorem, and a reconstructed image is obtained through inverse Fourier transform. And traversing the reference zero point to interference units (such as n) on the whole system to obtain n images, and finally superposing and synthesizing the final images of the target object.
Compared with the prior art, the digital distributed interference imaging system provided by the embodiment of the application has the following beneficial effects:
(1) the frequency domain space coverage rate is greatly improved
Compared with the prior art, because each local object light is digitized, any two object lights can be paired, and then the intensity and phase information of the corresponding frequency point of the frequency domain space is obtained based on the Van citt-Zernike theorem (Van citter-Zernike theorem). Because the object light pair is not limited, each object light can participate in the pairing for many times according to the design requirement of frequency domain space frequency coverage maximization, and therefore frequency domain space full coverage in the real sense can be achieved.
(2) Strong expansibility
Because the adjacent chips (micromirror arrays) are connected by the reference light fiber, the chips are physically relatively independent, and when a new chip is added, only the reference light fiber or the preset waveguide needs to be connected to the reference light input interface of the chip. The chip number expansion is not limited.
(3) Distributed permutation security is high
Each chip (micro mirror array) is relatively independent, in the chip array, a single chip fails, other chips are not influenced to continue to work, and high-quality object images can be continuously obtained by changing an interference baseline design scheme.
(4) Compatible with the existing silicon-based CMOS process, and convenient for large-scale processing and manufacturing
The prior design is not suitable for low-cost large-scale manufacturing, because the long baseline interference needs to be processed by a long waveguide and then a large-size chip, which is opposite to the current mainstream chip manufacturing development direction, the manufacturing cost is greatly increased; under the requirement that the length of an interference baseline can be adjusted at will, the size of a single chip can be reduced to 25mm X32 mm, the method is compatible with a mainstream photoetching exposure process, the structure of a single interference array (single chip) in a distributed interference array is consistent, the utilization rate of a photoetching mask is improved, a large number of plate making is avoided, and therefore the method can be used for manufacturing the mask in a large scale at a low cost.
(5) Reduction of object-light transmission loss
In remote detection, the object light signal is very weak after being transmitted through a remote space, so that the imaging detection system is required to have higher sensitivity. The long interference base line of the prior system design needs to be assisted by the long waveguide, so that the loss of weak object light is further increased after the weak object light is transmitted by the long waveguide, and great challenge is brought to signal detection; the object-light pairing interference is completed by the operation of digitalized object-light information without the help of long-distance transmission of a waveguide; the digitization process of the object optical signal only needs local short-distance waveguide transmission, and the stronger object optical signal can be ensured, so that the accurate digitization signal and the clear image can be obtained.
It should be noted that:
in this application, unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may comprise direct contact of the first and second features, or may comprise contact of the first and second features not directly but through another feature in between. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.
The following disclosure provides many different embodiments or examples for implementing different features of the application. In order to simplify the disclosure of the present application, specific example components and arrangements are described below. Of course, they are merely examples and are not intended to limit the present application. Moreover, the present application may repeat reference numerals and/or letters in the various examples, such repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed. In addition, examples of various specific processes and materials are provided herein, but one of ordinary skill in the art may recognize applications of other processes and/or use of other materials.
In the description herein, references to the description of the terms "one embodiment," "some embodiments," "an illustrative embodiment," "an example," "a specific example," or "some examples" or the like mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present application. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
While embodiments of the present application have been shown and described, it will be understood by those of ordinary skill in the art that: numerous changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the application, the scope of which is defined by the claims and their equivalents.
Claims (6)
1. A digitally distributed interferometric imaging system, comprising: the device comprises a reference light unit, an object light information acquisition unit and an image reconstruction unit; the object light information acquisition unit comprises a micro-mirror layer, a waveguide layer and a digitization layer;
the reference light unit is used for emitting coherent reference light;
the micro-mirror layer comprises a plurality of micro-mirrors, the micro-mirrors form a plurality of micro-mirror arrays, and the micro-mirror arrays are distributed and used for discretely collecting object light of a target object;
the waveguide layer comprises a plurality of interference units, the interference units form a plurality of interference unit arrays, the interference unit arrays are distributed and are arranged in a one-to-one correspondence mode with the micromirrors, the interference units are connected with the reference light unit through waveguides, and the reference light and the object light are interfered in the interference units;
the digital layer is used for converting an interference result of the reference light and the object light output by the interference unit into an analog electric signal, amplifying and filtering the analog electric signal, performing analog-to-digital conversion to finally generate digital information corresponding to the interference result, and demodulating the object light information digitized by the target object from the digital information by utilizing the known information of the reference light;
the image reconstruction unit is used for reconstructing an image of a target object according to a preset interference baseline design scheme, the position information of each micromirror and object light information corresponding to the discretization object light collected by the micromirror; the interference baseline design scheme comprises interference baseline vectors formed by pairing all two micromirrors.
2. The digital distributed interference imaging system of claim 1, wherein the waveguide layer comprises a plurality of interference unit arrays, each interference unit array comprises a plurality of interference units, and each interference unit array is connected with the reference light unit through a waveguide or an optical fiber respectively.
3. The digital distributed interference imaging system of claim 2, wherein the interference unit comprises a vertical coupler, a first phase shifter, a second phase shifter, and an interference component;
the vertical coupler is connected with the interference component through a waveguide, the first phase shifter is arranged between the reference light unit and the interference component, and the second phase shifter is arranged in the interference component;
the object light is collected by the micro mirror and enters the interference part through the vertical coupler, the reference light enters the interference part after passing through the first phase shifter to unify the phase, the phase is adjusted to a preset phase through the second phase shifter, and the reference light after adjusting the phase interferes with the object light in the interference part.
4. The digital distributed interference imaging system of claim 1, wherein the digitizing layer comprises a plurality of light detection components, analog electrical signal processing circuitry, and analog/digital conversion circuitry; the plurality of optical detection components are distributed and are arranged in one-to-one correspondence with the plurality of interference units;
the optical detection component is used for detecting the interference result in the corresponding interference unit and converting the interference result into an analog electric signal;
the analog electric signal processing circuit is used for amplifying and filtering the analog electric signals output by each optical detection component;
and the analog/digital conversion circuit converts the processed analog electric signal into a digital signal to obtain digital information corresponding to the interference result.
5. The digital distributed interference imaging system of claim 1, wherein the reference light unit is a coherent light source, and the coherent light source is a pulsed laser, an optical comb, or a continuous laser with spaced light.
6. The digital distributed interference imaging system of any one of claims 1 to 5 wherein the object light information comprises amplitude information and phase information.
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