CN114993472A - Bionic multispectral polarization single-pixel imaging device and method based on nerve overlapping compound eye - Google Patents

Abstract

The invention relates to a bionic multispectral polarization single-pixel imaging device and method based on nerve overlapped compound eyes, wherein the device comprises: a substrate; a plurality of sub-eyes; the sub-eyes are uniformly distributed on the substrate, and each sub-eye consists of at least one optical fiber; the front end of each imaging channel consists of optical fibers in the same position in each sub-eye, and the rear end of each imaging channel consists of optical fibers in the same position in each sub-eye which are fixed together; at least one filter or polarizer located at the rear end of the imaging channel; and at least one single pixel detector located behind each filter or polarizer. The imaging device provided by the invention has the advantages of compact structure, small occupied space, low manufacturing cost, large imaging field angle, high imaging dynamic range and high target identification efficiency.

Description

A biomimetic multispectral polarization single-pixel imaging device and method based on neural overlapping compound eyes

technical field

The invention relates to the technical fields of bionic compound eyes, single-pixel imaging and target recognition, and in particular relates to a bionic multispectral polarization single-pixel imaging device and method based on neural overlapping compound eyes.

Background technique

Target material identification is of great significance and application value for military reconnaissance, deep space exploration, environmental monitoring, resource assessment, forensic identification, biomedicine and other fields. Commonly used methods include radar, sonar, infrared imaging, multispectral imaging, and polarization imaging. and many more. Each of these methods has its own advantages and limitations.

For example, before using radar for target recognition, it is necessary to transmit electromagnetic waves to the target, which is not only very susceptible to interference from various external factors, but also cannot be passively recognized. Sonar uses sound waves in water to detect, and sound waves can be affected by a variety of conditions in seawater. Although infrared image technology itself is not susceptible to interference and can realize real-time monitoring throughout the day, the infrared stealth technology for it has also developed rapidly, hindering its further and wider application. The core of spectral identification technology is that different substances have different spectra, but this method often occurs when different substances have the same spectrum. Although polarization detection can not be affected by external environmental changes and interference, it lacks the ability to accurately detect targets with low contrast.

In order to improve and enhance the effect of target recognition, many researchers propose a target recognition technology that combines multispectral imaging technology and polarization imaging technology, which is called spectral polarization imaging technology. This technology can obtain two-dimensional spatial information, one-dimensional spectral information and polarization state information of the target. At present, various types of spectral polarization imagers are mainly improved from the previous imaging spectrometers, and their essence can be divided into two categories. One is time-sharing imaging, and the other is partition imaging. The typical representatives of time-sharing imaging are spectral polarization imagers based on rotating filters and polarizers, spectral imagers based on acousto-optic/liquid crystal tunable filters, and Fourier spectral polarization imagers. At the cost of obtaining multi-class information of the target. Partition imaging is to obtain all spectral information and polarization information in one exposure, including computational tomography spectral polarization imager and compressed spectral polarization imager proposed in recent years, but its algorithm is more complex, the settlement time is long, and it also At the expense of spectral accuracy.

All the above-mentioned spectral polarization imagers are improved on the basis of traditional single-aperture cameras, and have many limitations of traditional cameras, such as the imaging field of view is small, and increasing the field of view will introduce large image distortion. , The dynamic range is small, there are time periods that cannot work in deep space exploration, and the amount of image data is large, which has high requirements for data transmission. And so far, no matter what kind of spectral polarization imager there is a problem of low efficiency.

SUMMARY OF THE INVENTION

In order to solve the above-mentioned technical problems, the present invention provides a bionic multispectral polarization single-pixel imaging device and method based on nerve overlapping compound eyes.

The technical solution of the present invention is: a bionic multispectral polarization single-pixel imaging device based on nerve overlapping compound eyes, comprising:

base;

a plurality of sub-eyes; a plurality of the sub-eyes are evenly distributed on the base, and each of the sub-eyes is fixed by a plurality of optical fibers;

Multiple groups of imaging channels, the front end of each group of imaging channels is composed of optical fibers in the same position in each of the sub-eyes, and the rear end is composed of optical fibers in the same position in each of the sub-eyes fixed together;

At least one filter or polarizer, located at the rear end of each group of the imaging channels;

and at least one single-pixel detector behind each of said filters or polarizers.

Compared with the prior art, the present invention has the following advantages:

The invention discloses a bionic multi-spectral polarization single-pixel imaging device based on neural overlapping compound eyes. The single-pixel imaging of a target object is performed by constructing a single-pixel optical path, and the multi-layer spatial information of the object is obtained by using a compound eye system in conjunction with a filter and a polarizer. The target can be identified by simple calculation, and the device has compact structure, small footprint, low manufacturing cost, large imaging field of view, high imaging dynamic range and high target recognition efficiency.

Description of drawings

FIG. 1 is a schematic structural diagram of a bionic multispectral polarization single-pixel imaging device based on nerve overlapping compound eyes according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of the position of the optical fiber in the neutron eye according to the embodiment of the present invention;

3 is a schematic diagram of an optical path in a bionic multispectral polarization single-pixel imaging method based on a compound eye with overlapping nerves according to an embodiment of the present invention.

Detailed ways

The invention provides a bionic multispectral polarization single-pixel imaging device based on nerve overlapping compound eyes, which has compact structure, small footprint, low manufacturing cost, large imaging field angle, high imaging dynamic range and high target recognition efficiency.

In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below through specific implementation and in conjunction with the accompanying drawings.

Example 1

As shown in FIG. 1 , an embodiment of the present invention provides a bionic multispectral polarization single-pixel imaging device based on neural overlapping compound eyes, including:

Substrate 101; the shape of the substrate can be plane, curved or other shapes. In the embodiment of the present invention, the substrate adopts a hemispherical curved surface shape;

A plurality of sub-eyes 102; a plurality of sub-eyes are evenly distributed on the substrate, and each sub-eye is fixed by at least one optical fiber; when the sub-eye is composed of multiple optical fibers, number each fiber in each sub-eye, as shown in Figure 2 As shown, it is necessary to ensure that the fiber numbers of each sub-eye at the same position are consistent; and the front and rear end faces of all fibers need to be ground and polished;

At least one group of imaging channels 103, the front end of each group of imaging channels is composed of optical fibers in the same position in each sub-eye, that is, the No. 1 optical fiber of each sub-eye is used as the front end of the first group of imaging channels, and the No. 2 optical fiber of each sub-eye is used as the front end of the first group of imaging channels. The optical fibers are used as the front and rear ends of the second group of imaging channels, and so on; group, the rear end of the No. 2 fiber is fixed as a group, and so on. When the sub-eye contains n fibers (n≥1), n groups of imaging channels can be obtained, and the number of fibers included in each group of imaging channels is the total number of sub-eyes, and the front end of each group of imaging channels follows each sub-eye. It is evenly distributed on the base, and the rear end is composed of optical fibers with the same position number in each sub-eye fixed together, and the front and rear surfaces of the optical fibers in each group of imaging channels need to be flat and consistent;

At least one filter or polarizer 104 is located at the rear end of each group of imaging channels; a filter or a polarizer is placed behind each group of imaging channels; when there are multiple groups of imaging channels, the rear end of all imaging channels can be installed as required Place filters or polarizers, or place filters or polarizers with different proportions; as shown in Figure 2, in the embodiment of the present invention, each sub-eye contains 7 optical fibers, forming 7 sets of imaging channels, and placed after the imaging channels respectively 3 polarizers and 4 filters, corresponding to 3 polarization channels and 4 spectral channels respectively;

And at least one single-pixel detector 105, located behind each filter or polarizer, for collecting the light intensity transmitted by each group of imaging channels.

The bionic multi-spectral polarization single-pixel imaging device based on the neural overlapping compound eye proposed by the present invention performs single-pixel imaging on the target object by building a single-pixel optical path, and uses the compound eye system to cooperate with filters and polarizers to obtain the multi-layer spatial information of the target object. The device is compact in structure, occupies small space, uses plastic optical fiber as raw material, and has low cost.

Embodiment 2

Based on the device provided in the first embodiment, a bionic multispectral polarization single-pixel imaging method based on neural overlapping compound eyes is realized. A biomimetic multispectral polarization single-pixel imaging device 204, an imaging channel 103, a filter and polarizer array 104, and a single-pixel detector array 105 for a compound eye with overlapping nerves;

Specific steps are as follows:

S1: Obtain the mask pattern required for single-pixel imaging and upload it to the spatial light modulator;

S2: Place the object to be measured in a dark environment, and the light emitted by the light source transmitter is modulated by the spatial light modulator and reflected on the object to be measured; the sub-eye of a bionic multispectral polarization single-pixel imaging device based on neural overlapping compound eyes Collect the total light intensity generated by the interaction between the mask pattern and the object to be tested, and transmit it through the imaging channel;

For a single-pixel imaging optical path, a light source with a wider bandwidth is required, and the bandwidth of the selected light source needs to include the spectrum of the selected multiple filters. In the embodiment of the present invention, coal and stone are selected together as the object to be measured, and placed in a light-proof environment, and the light emitted by the light source emitter is modulated by the spatial light modulator and reflected on the object to be measured.

Let P _i (x, y) be the mask pattern used for the i-th measurement, where i=1, 2, 3, ..., M, M is the total number of measurements, and I(x, y) represents the space of the object to be measured coordinate. After the total light intensity generated by the interaction of P _i (x, y) and I (x, y) is collected by the sub-eyes of the bionic multispectral polarization single-pixel imaging device based on neural overlapping compound eyes, since each sub-eye in the embodiment of the present invention It consists of 7 optical fibers, as shown in Figure 2, so the total light intensity is divided into 7 parts, which are respectively transmitted by each group of imaging channels;

S3: Use a filter or a polarizer, or a combination of a filter and a polarizer to modulate the total light intensity and then enter the single-pixel detector to obtain light intensity information;

In the embodiment of the present invention, an array of 4 filters and 3 polarizers is combined and placed at the rear end of the imaging channel, wherein the imaging spectrum of the 4 filters is 480 (20 nm) nm, 650 (12 nm) nm, 800 ( 25nm)nm and 950(50nm)nm, and the angles of the 3 polarizers are 0°, 60° and 120°, respectively, and the total light intensity modulated by 4 filters and 3 polarizers enters single-pixel detection , and the light intensity information, namely S _i , is recorded by the single-pixel detector, as shown in formula (1):

S _i =∫∫P _i (x,y)I(x,y)dxdy (1)

S4: Calculate the multispectral image and the polarization image according to the light intensity information; perform the band operation and the polarization degree and polarization angle calculation on the multispectral image and the polarization image respectively;

Since both S _i and P _i (x, y) are known quantities at this time, 4 spectra of different wavelength bands and 3 polarization images of different polarization states of the object to be measured can be obtained by calculation;

According to 7 pictures with the same content in 4 different bands and 3 different polarization states; select the interesting part of the picture to perform band calculation and calculation of polarization degree and polarization angle respectively;

The calculation formulas for the degree of polarization (DOLP) and the angle of polarization (AOLP) are as follows:

Among them, I(0°), I(60°), and I(120°) represent the light intensity of the linearly polarized component of the light wave in the directions of 0°, 60° and 120°, respectively, and I, Q, and U are Stowe The first 3 parameters of the Cox vector;

S5: Compare the calculation result with the data in the database to obtain the type of the object to be measured.

Comparing the obtained spectral data of the object to be measured, its degree of polarization and polarization angle with the data in the database, it is obtained that the types of the object to be measured are coal and stone respectively, so as to complete the target recognition work.

The bionic multi-spectral polarization single-pixel imaging method based on neural overlapping compound eyes provided by the present invention can obtain multiple images of the object to be tested with multiple different spectral bands and multiple polarization angles at one time, and these images include two images of the object to be tested. Dimensional space information: spectral information and polarization information. After simple processing of the picture information, the spatial multi-layer information of the object to be measured can be obtained, and it can be compared with the spectral and polarization databases of various substances measured in advance to achieve The purpose of identifying the substance of the measured object.

The embodiment of the present invention adopts single-pixel imaging as the imaging method, which outputs one-dimensional light intensity information, and its data volume is much smaller than other spectral polarization imagers, which is convenient for the instrument to work for a long time and data transmission. In addition, due to the characteristics of single-pixel imaging, in addition to the different spectrum and polarization information carried, the two-dimensional spatial information of the object on the obtained multiple images is exactly the same, and subsequent image registration work is not required, and the efficiency is high.

The embodiment of the present invention adopts an active single-pixel imaging method, which is also applicable to passive single-pixel imaging in theory. When the passive single-pixel imaging method is used, another great advantage of single-pixel imaging can be brought into play because the experiment is performed without avoiding light, which has a dynamic range far greater than that of ordinary cameras. By adjusting the gain of the single-pixel detector, imaging can be performed in a large dynamic range. In addition, passive single-pixel imaging has outstanding imaging performance under low light conditions.

The above embodiments are provided for the purpose of describing the present invention only, and are not intended to limit the scope of the present invention. The scope of the invention is defined by the appended claims. Various equivalent replacements and modifications made without departing from the spirit and principle of the present invention should be included within the scope of the present invention.

Claims (5)

1. A bionic multispectral polarization single-pixel imaging device based on nerve overlapped compound eyes is characterized by comprising:

a substrate;

a plurality of sub-eyes; the sub-eyes are uniformly distributed on the substrate, and each sub-eye is composed of at least one optical fiber;

the front end of each imaging channel consists of optical fibers in the same positions in the sub-eyes, and the rear end of each imaging channel consists of optical fibers in the same positions in the sub-eyes which are fixed together;

at least one filter or polarizer located at the rear end of each set of imaging channels;

and at least one single pixel detector located behind each of the filters or polarizers.

2. The neuro-superimposable compound eye-based biomimetic multi-spectral polarization single pixel imaging device according to claim 1, wherein said substrate is in a curved shape.

3. The neuro-overlay compound eye-based biomimetic multi-spectral polarization single-pixel imaging device according to claim 1, wherein each sub-eye comprises at least 1 fiber.

4. The biomimetic multispectral polarized single-pixel imaging device based on neuro-overlap compound eye according to claim 1, comprising at least 1 filter or 1 polarizer.

5. The bionic multispectral polarization single-pixel imaging method based on the neural overlapping compound eye is characterized in that the bionic multispectral polarization single-pixel imaging device based on the neural overlapping compound eye according to any one of claims 1 to 4 comprises the following steps:

s1: acquiring a mask pattern required by single-pixel imaging, and uploading the mask pattern to a spatial light modulator;

s2: placing an object to be measured in a light-shading environment, and reflecting light emitted by a light source emitter to the object to be measured through modulation of the spatial light modulator; the sub-eye of the bionic multispectral polarization single-pixel imaging device based on the nerve overlapped compound eye collects total light intensity generated after the mask pattern interacts with the object to be detected and transmits the total light intensity through an imaging channel;

s3: modulating the total light intensity by using a filter or a polaroid or a combination of the filter and the polaroid, and then entering a single-pixel detector to obtain light intensity information;

s4: calculating to obtain a multispectral image and a polarization image according to the light intensity information; respectively carrying out band operation and calculation of polarization degree and polarization angle on the multispectral image and the polarization image;

s5: and comparing the calculation result with data in a database to obtain the type of the object to be detected.

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