Large dynamic range imaging device and method

Abstract

The invention discloses a large dynamic range imaging device and method, and relates to the technical field of remote sensing imaging, in the device, a rotary scanning assembly moves to a corresponding position according to a rotation instruction, and transmits received radiation to an optical telescope assembly, so that the radiation is converged to a light splitting assembly; the light splitting assembly divides radiation into visible light and infrared rays which are respectively sent to the visible light assembly and the infrared assembly; the visible light assembly performs focusing and multi-channel low-light detection on the received visible light to obtain visible light signal data; the infrared assembly performs collimation, focusing and multi-channel infrared detection on the received infrared rays to obtain infrared radiation signal data; the controller carries out amplification processing on the visible light signal data and the infrared radiation signal data, data fusion is carried out to obtain a ground object target image, sight angle information of a corresponding ground object target is determined based on the ground object target image, and then a rotation instruction is generated and sent to the rotation scanning assembly. The remote sensing image with rich and complete data information can be obtained under low illumination.

Description

Technical Field

[0001] The present application relates to the field of remote sensing imaging technology, and in particular to a large dynamic range imaging device and method. Background Art

[0002] Traditional visible light imaging systems have difficulty working under weak illumination conditions. The acquisition of image information under low illumination can only rely on infrared. However, since visible light images are usually superior to infrared in terms of resolution and signal-to-noise ratio, for example, in the dawn-dusk orbit, some special details and cloud changes can be observed using low-light images, which helps to distinguish targets, but are not easy to find in infrared images. In summary, it is difficult for existing technologies to obtain remote sensing images with rich and complete data information under low illumination. Summary of the invention

[0003] The purpose of this application is to provide a large dynamic range imaging device and method, which can obtain remote sensing images with rich and complete data information under low illumination.

[0004] To achieve the above objectives, this application provides the following solutions:

[0005] In a first aspect, the present application provides a large dynamic range imaging device, including a rotating scanning component, an optical telescope component, a spectroscopic component, an infrared component, a visible light component, and a controller;

[0006] The rotating scanning assembly is used to: receive a rotation instruction from the controller; receive radiation from the earth; move to a corresponding position according to the rotation instruction, and send the received radiation into the optical telescope assembly;

[0007] The optical telescope assembly is used to: focus the received radiation to the light splitting assembly;

[0008] The light splitting component is used to: split the received radiation into visible light and infrared light, and send the visible light into the visible light component and send the infrared light into the infrared component;

[0009] The visible light component is used to focus the received visible light and perform multi-channel low-light detection to obtain visible light signal data; the infrared component is used to collimate, focus and perform multi-channel infrared detection to obtain infrared radiation signal data;

[0010] The controller is connected to the visible light component and the infrared component respectively, and is used to: amplify the visible light signal data and the infrared radiation signal data, and then perform data fusion to obtain a ground object target image; determine the line of sight angle information of the corresponding ground object target based on the ground object target image; generate a rotation instruction according to the line of sight angle information, and send it to the rotating scanning component; wherein the rotation instruction is used to adjust the position of the rotating scanning component so that the ground object target is in the center of the imaging field of view within a preset time length.

[0011] In a second aspect, the present application provides a large dynamic range imaging method, which is applied to a large dynamic range imaging device, and the large dynamic range imaging method comprises:

[0012] A rotating scanning assembly is used to move to a corresponding position according to a rotation command issued by a controller, and the received radiation is sent to an optical telescope assembly;

[0013] The optical telescope assembly is used to converge the received radiation to the light splitting assembly, and the light splitting assembly is used to split the radiation into visible light and infrared light, and the visible light is sent to the visible light assembly, and the infrared light is sent to the infrared assembly;

[0014] The visible light component is used to focus and perform multi-channel low-light detection on the received visible light to obtain visible light signal data, and the infrared component is used to collimate, focus and perform multi-channel infrared detection on the received infrared light to obtain infrared radiation signal data;

[0015] The controller is used to amplify the visible light signal data and the infrared radiation signal data, and then data fusion is performed to obtain a ground object target image;

[0016] The controller is used to determine the sight angle information of the corresponding ground object based on the ground object image, and generate a rotation instruction according to the sight angle information, and send it to the rotating scanning component; wherein the rotation instruction is used to adjust the position of the rotating scanning component so that the ground object is in the center of the imaging field of view within a preset time length.

[0017] According to the specific embodiments provided by the present application, the present application has the following technical effects: the present application provides a large dynamic range imaging device and method, which uses a rotating scanning component, an optical telescope component, a spectroscopic component, an infrared component, a visible light component and a controller to perform multi-channel detection of low light, visible light and infrared rays to achieve complementary use of multiple spectral bands; wherein data fusion is performed by the controller to achieve integrated imaging of low light, visible light and infrared multi-spectral bands, and more and richer remote sensing information of ground objects can be obtained; and the rotating scanning component provided therein can achieve wide coverage of ground object targets. In summary, the present application solves the problem of obtaining remote sensing image information under low illumination. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 This is a schematic structural diagram of a large dynamic range imaging device in one embodiment of the present application;

[0020] Figure 2 A schematic diagram of a visible light detector provided in one embodiment of the present application;

[0021] Figure 3 A schematic diagram of an infrared detector provided in one embodiment of the present application;

[0022] Figure 4 This is a working principle diagram of a large dynamic range imaging device in one embodiment of the present application.

[0023] Figure numerals: 1-scanning mirror, 2-torque motor, 3-code disk, 4-scanning mirror carbon fiber cover, 5-optical telescope assembly, 6-spectrometric assembly, 7-infrared collimation optical assembly, 8-cold optical lens group, 9-infrared detector, 10-visible light focusing assembly, 11-visible light detector, 12-controller. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0025] Due to differences in lighting conditions, under the same imaging parameters, images of ground objects in the same field of view may have appropriate exposure and rich details in some areas, while images of other areas may be underexposed or overexposed, with serious loss of details. The receiving system needs to take into account a large dynamic range to provide images with richer layers. In view of this, the present application provides a large dynamic range imaging device and method, which has a large detection width, a large detection dynamic range, and multiple detection channels, which can simultaneously meet the needs of low light, visible light, and infrared detection, and achieve clear imaging of targets with different light intensities or uneven illumination at one time.

[0026] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0027] In an exemplary embodiment, Figure 1 As shown, a large dynamic range imaging device is provided, including a rotating scanning component, an optical telescope component 5, a spectroscopic component 6, an infrared component, a visible light component and a controller 12.

[0028] The rotating scanning component is used to: receive a rotation instruction from the controller 12 ; receive radiation from the earth; move to a corresponding position according to the rotation instruction, and send the received radiation into the optical telescope component 5 .

[0029] Specifically, the rotating scanning assembly includes a scanning mirror 1, a torque motor 2, a code disc 3 and a scanning mirror carbon fiber cover 4. The scanning mirror 1 is tiltedly arranged inside the scanning mirror carbon fiber cover 4, the torque motor 2 is arranged on the outer surface of the scanning mirror carbon fiber cover 4, and the code disc 3 is arranged on the torque motor 2. The code disc 3 is used to receive a rotation instruction from the controller 12, and determine the mechanical geometric displacement according to the rotation instruction, which has high accuracy. The torque motor 2 is used to rotate according to the mechanical geometric displacement, and drive the scanning mirror carbon fiber cover 4 and the scanning mirror 1 to rotate; in an application example, the torque motor 2 is a DC torque motor. The scanning mirror 1 is used to receive radiation from the earth and send the received radiation into the optical telescope assembly 5.

[0030] The optical telescope component 5 is used to converge the received radiation to the light splitting component 6; specifically, the optical telescope component 5 is a coaxial reflective telescope structure.

[0031] The light splitting component 6 is used to split the received radiation into visible light and infrared light, and send the visible light into the visible light component and send the infrared light into the infrared component. In an application example, the light splitting component 6 mainly includes a color separation plate.

[0032] The visible light component is used to focus the received visible light and perform multi-channel low-light detection to obtain visible light signal data; the infrared component is used to collimate, focus and perform multi-channel infrared detection to obtain infrared radiation signal data.

[0033] Specifically, the infrared component includes an infrared collimating optical component 7, a cold optical lens group 8 and an infrared detector 9 which are arranged in sequence. The infrared collimating optical component 7 includes a collimating lens and an infrared bandpass filter which are arranged in sequence; the cold optical lens group 8 is a low-temperature cooling converging lens group; and the infrared detector 9 is a mercury cadmium telluride detector. Furthermore, the infrared detector 9 is used to realize multi-channel infrared detection, and the multi-channel includes a medium-wave infrared detection channel, a medium-long-wave infrared detection channel and a long-wave infrared detection channel; the wavelength ranges of the three waves of medium wave, medium-long wave and long wave which appear therein can be manually set as needed. The medium-wave infrared detection channel, the medium-long-wave infrared detection channel and the long-wave infrared detection channel each include at least one column, and the number of pixels in each column is the same.

[0034] like Figure 2 As shown, the medium-wave infrared detection channel, the medium- and long-wave infrared detection channel, and the long-wave infrared detection channel each include a column, and the number of pixels in each column is 40 (designable according to the scanning rate), and each pixel can cover the temperature range of 180K-380K.

[0035] The visible light component includes a visible light focusing component 10 and a visible light detector 11 which are arranged in sequence; wherein the visible light focusing component 10 includes at least one converging lens; the visible light detector 11 has a detection band of 0.45um to 1.0um, has a low-light detection capability, is suitable for the brightness of moonlight to sunlight, and is mainly used for detecting cloud images on the earth's surface, including the radiation of the moon and starlight at night, and can detect a radiance dynamic range of up to 10 7 The visible light detector is used to realize multi-channel low-light detection, and the multi-channel includes a low-end channel, a middle-end channel and a high-end channel, and the low-end channel, the middle-end channel and the high-end channel are arranged side by side on the same focal plane; the low-end channel, the middle-end channel and the high-end channel each include at least one column, and the number of pixels in each column is the same.

[0036] like Figure 3As shown, the visible light detector 11 adopts a three-stage design, which is divided into a low-end channel (indicated by L), a middle-end channel (indicated by M) and a high-end channel (indicated by H), realizing low-light visible light split window detection, which can achieve a dynamic range coverage of seven orders of magnitude. The high-end channel and the middle-end channel have one column for each channel, and each column has 40 yuan (which can be designed according to the scanning rate). The low-end channel adopts nine columns and scans to improve the sensitivity, and each column has 40 yuan (which can be designed according to the scanning rate), and the size of each pixel is 140μm.

[0037] The controller 12 is connected to the visible light component and the infrared component respectively, and the controller 12 is used to: amplify the visible light signal data and the infrared radiation signal data, and then perform data fusion to obtain a ground object target image; determine the line of sight angle information of the corresponding ground object target based on the ground object target image; generate a rotation instruction according to the line of sight angle information, and send it to the rotating scanning component; wherein the rotation instruction is used to adjust the position of the rotating scanning component so that the ground object target is in the center of the imaging field of view within a preset time length.

[0038] like Figure 4 As shown, the working process of the large dynamic range imaging device includes: radiation from the earth is transmitted through a rotating scanning component (corresponding to Figure 4 The infrared radiation passes through the infrared collimating optical component 7 and the cold optical lens group 8, and is focused on the infrared detector 9 for imaging; the visible light path passes through the visible light focusing component 10, and is focused on the low-light visible light split window detector (i.e., the visible light detector 11) for imaging. After that, the controller 12 amplifies the electrical signals received on the infrared detector 9 and the visible light detector 11, and then fuses the infrared image and the low-light visible light image, and obtains the sight angle information of the ground object target through image preprocessing, feature extraction, sight angle solution, etc. Finally, the sight angle information of the ground object target obtained by real-time solution is transmitted to the code disk 3 as a rotation instruction, and the code disk 3 gives a digital quantity corresponding to the sight angle information, i.e., the mechanical geometric displacement, and automatically adjusts the parameters of the rotation mechanism to ensure that the ground object target always remains in the center of the field of view of the imaging system.

[0039] Based on the same inventive concept, an embodiment of the present application also provides a large dynamic range imaging method applied to the above-mentioned large dynamic range imaging device. The implementation solution for solving the problem provided by the method is similar to the implementation solution recorded in the above-mentioned device. Therefore, the specific limitations in one or more method embodiments provided below can refer to the limitations on the device above and will not be repeated here.

[0040] The large dynamic range imaging method comprises:

[0041] Step 100, using a rotating scanning assembly to move to a corresponding position according to a rotation instruction issued by a controller, and sending the received radiation to an optical telescope assembly.

[0042] Step 200, using the optical telescope assembly to converge the received radiation to the spectroscopic assembly, and the spectroscopic assembly separates the radiation into visible light and infrared light, and sends the visible light to the visible light assembly and the infrared light to the infrared assembly.

[0043] Step 300, using the visible light component to focus and perform multi-channel low-light detection on the received visible light to obtain visible light signal data, and using the infrared component to collimate, focus and perform multi-channel infrared detection on the received infrared light to obtain infrared radiation signal data.

[0044] Step 400: amplify the visible light signal data and the infrared radiation signal data using the controller, and then perform data fusion to obtain a ground object target image.

[0045] Step 500, using the controller to determine the line of sight angle information of the corresponding ground object based on the ground object image, and generating a rotation instruction according to the line of sight angle information, and sending it to the rotating scanning component; wherein the rotation instruction is used to adjust the position of the rotating scanning component so that the ground object is in the center of the imaging field of view within a preset time length.

[0046] Among them, the controller is used to determine the sight angle information of the corresponding ground object target based on the ground object target image, including: using a preset algorithm in the controller to sequentially preprocess, extract features, and calculate the sight angle of the ground object target image to obtain the sight angle information of the corresponding ground object target.

[0047] In summary, the present application solves the problems of large dynamic range wide-width long-line imaging, extremely low illumination imaging, and low-light visible infrared integrated detection of ground features. The present application adopts a common optical path multi-element parallel scanning integrated detection imaging method, and achieves wide coverage of ground objects through a rotating scanning mechanism; a common main optical telescope assembly is used, and a spectroscopic assembly is used to separate visible light and infrared light; the low-light and visible light detection channels are arranged side by side on the same focal plane, and a low-light visible light split window detector is used. The dynamic range is divided into three channels: high-end, mid-end, and low-end. Each channel at the mid-end and high-end has one column, and the low-end uses nine columns of parallel scanning to improve sensitivity, and the integration time of each column is adjustable; the infrared channel uses a mercury cadmium telluride detector structure packaged in a refrigerated Dewar package, including three channels: medium wave, medium-long wave, and long wave, which can cover a temperature range of 180K-380K. The present application can be used for cloud map acquisition, fire point detection, etc., and serves the fields of civil meteorology and commercial aerospace.

[0048] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0049] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and core ideas of this application. At the same time, for those skilled in the art, according to the ideas of this application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting this application.

Claims

1. A large dynamic range imaging device, characterized in that: The large dynamic range imaging device comprises a rotating scanning component, an optical telescope component, a spectroscopic component, an infrared component, a visible light component and a controller; The rotating scanning assembly is used to: receive a rotation instruction from the controller; receive radiation from the earth; move to a corresponding position according to the rotation instruction, and send the received radiation into the optical telescope assembly; The optical telescope assembly is used to: focus the received radiation to the light splitting assembly; The light splitting component is used to: split the received radiation into visible light and infrared light, and send the visible light into the visible light component and send the infrared light into the infrared component; The visible light component is used to focus the received visible light and perform multi-channel low-light detection to obtain visible light signal data; the infrared component is used to collimate, focus and perform multi-channel infrared detection to obtain infrared radiation signal data; The controller is connected to the visible light component and the infrared component respectively, and is used to: amplify the visible light signal data and the infrared radiation signal data, and then perform data fusion to obtain a ground object target image; determine the line of sight angle information of the corresponding ground object target based on the ground object target image; generate a rotation instruction according to the line of sight angle information, and send it to the rotating scanning component; wherein the rotation instruction is used to adjust the position of the rotating scanning component so that the ground object target is in the center of the imaging field of view within a preset time length.

2. The large dynamic range imaging device according to claim 1, characterized in that: The rotating scanning assembly includes a scanning mirror, a torque motor, a code disc and a scanning mirror carbon fiber cover; The scanning mirror is tiltedly arranged inside the carbon fiber cover of the scanning mirror, the torque motor is arranged on the outer surface of the carbon fiber cover of the scanning mirror, and the code disk is arranged on the torque motor; The code disc is used to receive a rotation instruction from the controller and determine a mechanical geometric displacement according to the rotation instruction; the torque motor is used to rotate according to the mechanical geometric displacement and drive the scanning mirror carbon fiber cover and the scanning mirror to rotate; The scanning mirror is used to receive radiation from the earth and send the received radiation into the optical telescope assembly.

3. The large dynamic range imaging device according to claim 1, characterized in that: The optical telescope assembly is a coaxial reflective telescope structure.

4. The large dynamic range imaging device according to claim 1, characterized in that: The infrared component includes an infrared collimating optical component, a cold optical lens group and an infrared detector which are arranged in sequence; wherein the infrared collimating optical component includes a collimating lens and an infrared bandpass filter which are arranged in sequence; the cold optical lens group is a low-temperature cooled converging lens group; the infrared detector is used to realize multi-channel infrared detection, and the multi-channel includes a medium-wave infrared detection channel, a medium- and long-wave infrared detection channel and a long-wave infrared detection channel; the medium-wave infrared detection channel, the medium- and long-wave infrared detection channel and the long-wave infrared detection channel each include at least one column, and the number of pixels in each column is the same.

5. The large dynamic range imaging device according to claim 1, characterized in that: The visible light component includes a visible light focusing component and a visible light detector arranged in sequence; Wherein, the visible light focusing component includes at least one converging lens; the detection band of the visible light detector is 0.45um to 1.0um.

6. The large dynamic range imaging device according to claim 5, characterized in that: The visible light detector is used to realize multi-channel low-light detection, and the multi-channel includes a low-end channel, a middle-end channel and a high-end channel, and the low-end channel, the middle-end channel and the high-end channel are arranged side by side on the same focal plane; The low-end channel, the middle-end channel and the high-end channel each include at least one column, and the number of picture elements in each column is the same.

7. The large dynamic range imaging device according to claim 4, characterized in that: The infrared detector is a mercury cadmium telluride detector.

8. A large dynamic range imaging method, applied to the large dynamic range imaging device according to any one of claims 1 to 7, characterized in that: The large dynamic range imaging method comprises: A rotating scanning assembly is used to move to a corresponding position according to a rotation command issued by a controller, and the received radiation is sent to an optical telescope assembly; The optical telescope assembly is used to converge the received radiation to the light splitting assembly, and the light splitting assembly is used to split the radiation into visible light and infrared light, and the visible light is sent to the visible light assembly, and the infrared light is sent to the infrared assembly; The visible light component is used to focus and perform multi-channel low-light detection on the received visible light to obtain visible light signal data, and the infrared component is used to collimate, focus and perform multi-channel infrared detection on the received infrared light to obtain infrared radiation signal data; The controller is used to amplify the visible light signal data and the infrared radiation signal data, and then data fusion is performed to obtain a ground object target image; The controller is used to determine the sight angle information of the corresponding ground object based on the ground object image, and generate a rotation instruction according to the sight angle information, and send it to the rotating scanning component; wherein the rotation instruction is used to adjust the position of the rotating scanning component so that the ground object is in the center of the imaging field of view within a preset time length.

9. The large dynamic range imaging method according to claim 8, characterized in that: The controller is used to determine the sight angle information of the corresponding ground object target based on the ground object target image, including: using a preset algorithm in the controller to sequentially preprocess, extract features, and calculate the sight angle of the ground object target image to obtain the sight angle information of the corresponding ground object target.

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