CN114397255B - Wide-spectrum high-resolution video spectrum imaging system and method - Google Patents

Abstract

The invention belongs to the technical field of spectrum imaging, and particularly relates to a wide-spectrum high-resolution video spectrum imaging system and method. The technical defects of narrow working band range, less spectrum and low image resolution in the existing video spectrum imaging system based on the pixel coating light-splitting imaging mechanism are overcome. The imaging system comprises a front imaging optical system, a beam splitting component, an area array detector I, an area array detector II and an area array detector III; the incident broadband light beam is divided into two independent working wave bands through the light splitting component, and the two mosaic pixel film coating video multispectral area array detectors II and the area array detector III are respectively adopted for simultaneous reception, so that multispectral images in the working wave band range of 450nm-980nm can be obtained at one time. And (3) obtaining a high-resolution image through the area array detector I, and realizing high-image resolution reconstruction of the mosaic pixel film coating video multispectral area array detectors II and III by utilizing the high-resolution image through an image reconstruction algorithm, so that a high-resolution multispectral image can be finally obtained.

Description

A wide-band high-resolution video spectral imaging system and method

technical field

The invention belongs to the technical field of spectral imaging, and in particular relates to a wide-spectrum high-resolution video spectral imaging system and method.

Background technique

Video spectral imaging technology is the product of the combination of imaging technology and spectral technology. substitute role. With the rapid development of integrated optics, micro-electromechanical technology and precision machining technology, high-resolution, micro-spectral imaging technology has been developed rapidly.

For the research on light and small video spectral imaging technology, the current research and application is relatively more on the spectral imaging technology route based on pixel coating. Although the spectral imager developed based on this technical route has the outstanding technical characteristics of miniaturization and video spectral imaging, there are generally technical disadvantages such as narrow working band range, few spectral bands, and low image resolution, which limits this technology to a certain extent. Promotion and application of technology. For example, the Belgian IMEC company has developed a method based on CMOS chip mosaic pixel coating to realize the integrated filtering of multi-channel spectral bands. The company launched two mosaic pixel-coated video spectrum imagers, with a visible spectral range of 460nm-630nm and 16 spectral segments, and a near-infrared spectral range of 690nm-975nm with 25 spectral segments.

Contents of the invention

The purpose of the present invention is to provide a wide-spectrum high-resolution video spectral imaging system and method to solve the problems of narrow working band range, few spectral segments and low image resolution existing in the current video spectral imaging system based on the pixel coating spectroscopic imaging mechanism technical disadvantages, and the imaging system proposed by the present invention has the outstanding advantages of miniaturization and high integration.

Technical scheme of the present invention is:

A wide-spectrum high-resolution video spectrum imaging system, which is special in that it includes a front imaging optical system, a beam splitting component, an area array detector I, an area array detector II, and an area array detector III;

The front imaging optical system is used to image the target;

The beam splitting component is placed between the pre-imaging optical system and each area array detector, and is used to split the incident beam to obtain three beams with different wavelength ranges, and define the beam I with the beam range from λ _S to λ _L , Define the beam with a wavelength range of λ _S ~ λ _M as beam II; define the beam with a wavelength range of λ _M ~ λ _L as beam III; where λ _S < λ _M < λ _L , the wavelength range of the incident beam is the same as that of beam I The band range is the same;

The area array detector I has a working wavelength range from λ _S to λ _L and is used to receive the light beam I to obtain panchromatic high-resolution images;

The working band range of the area array detector II is λ _S ~ λ _M , which is used to receive the light beam II, and obtain video multispectral images covering the working band range of λ _S ~ λ _M ;

The working band range of the area array detector III is λ _M ~ λ _L , which is used to receive the light beam III and obtain video multispectral images covering the working band range of λ _M ~ λ _L .

Further, the above-mentioned light splitting component is a cemented prism component, including a first secondary reflection prism, a second secondary reflection prism and a transmission prism;

The AC surface of the first secondary reflection prism is glued to the DE surface of the second secondary reflection prism, and the EF surface of the second secondary reflection prism is glued to the GH surface of the transmission prism; the AC surface of the first secondary reflection prism The top is coated with a dichroic film; the EF surface of the second secondary reflection prism is coated with a dichroic film;

The AB surface of the first secondary reflective prism is used as the incident surface, the BC surface of the first secondary reflective prism is used as the outgoing surface of the beam I, the DF surface of the second secondary reflective prism is used as the outgoing surface of the beam II, and the transmission prism The PK surface is used as the exit surface of the beam III;

The incident light beam with a working wavelength range of λ _S ～ λ _L reaches the first secondary reflection prism through the pre-imaging optical system, passes through the light splitting film on the AC surface of the first secondary reflection prism, and divides the incident light beam according to a certain light splitting ratio Beams are divided into two parts, one part of which is the beam I reaches the AB surface of the first secondary reflection prism, and then exits from the BC surface through the reflection of the AB surface to reach the target surface of the area array detector I to obtain a panchromatic high-resolution image The other part of the light beam reaches the EF surface of the second secondary reflection prism, and the light beam with the working wavelength range of λ _S ～ λ _L is divided into the working wave band range of λ _S ～ λ _M and λ _M ～ through the dichroic film on it. Beam II and beam III of λ _L , wherein beam II is reflected by the DE surface of the second secondary reflection prism, exits from the DF surface of the second secondary reflection prism and reaches the target surface of the area array detector II, and the coverage λ _S The video multispectral image in the working band range of ~λ _M ; the beam III reaches the target surface of the area array detector III through the transmission prism, and the video multispectral image covering the working band range of λ _S ~ λ _M is obtained.

Further, the front imaging optical system is a transmission optical path structure, a total reflection optical path structure or a return optical path structure.

Further, the front imaging optical system is a camera system, a microscope system or a telephoto system.

Further, the target surface of the area array detector I is a target surface of a high-resolution broadband panchromatic photosensitive detector.

Further, the target surfaces of the area array detector II and the area array detector III are both mosaic pixel-coated video spectrum imaging detector target surfaces.

The present invention also provides a wide-spectrum high-resolution video spectral imaging method based on a wide-spectrum high-resolution video spectral imaging system, which is special in that it includes the following steps:

Step 1. Obtain panchromatic high-resolution images, video multispectral images covering the working band range of λ _S ~ λ _M and video multispectral images covering the working band range of λ _M ~ λ _L based on the wide-spectrum high-resolution video spectral imaging system ;

Step 2. Use panchromatic high-resolution images to perform high-resolution reconstruction of video multispectral images covering the working band range of λ _S ~ λ _M and video multispectral images covering the working band range of λ _M ~ λ _L to obtain high resolution rate multispectral image data.

Further, step 2 is specifically:

Step 2.1, extracting video multispectral images covering the working band range of λ _S ~ λ _M and each single-spectrum image data in the video multispectral images covering the working band range of λ _M ~ λ _L :

Extract all the positions corresponding to the pixels whose central wavelength is _λi on the target surface of the area array detector II and the target surface of the area array detector III, respectively, and then a single-spectrum low-resolution image with the central wavelength _λi can be obtained ;

Step 2.2, using the low-resolution image data of each single-spectrum segment and the panchromatic high-resolution image for reconstruction to obtain the high-resolution image data of the spectral segment.

Further, step 1 is specifically: the incident light beam with a working wavelength range of λ _S ~ λ _L reaches the first secondary reflection prism through the front imaging optical system, passes through the spectroscopic film on the AC surface of the first secondary reflection prism, The incident beam is divided into two parts according to a certain splitting ratio, and part of the beam, namely beam I, reaches the AB surface of the first secondary reflection prism, and then exits from the BC surface through the reflection of the AB surface to reach the target surface of the area array detector I. A full-color high-resolution image is obtained; another part of the light beam reaches the EF surface of the second secondary reflection prism, and the light beam with a working wavelength range of λ _S ~ λ _L is divided into a working wavelength range of λ through the dichroic film on it. Beam II and beam III of _S ～λ _M and λ _M ～λ _L , wherein beam II is reflected by the DE surface of the second secondary reflection prism, and exits from the DF surface of the second secondary reflection prism to reach the area detector Target surface II, to obtain video multispectral images covering the working band range of λ _S ~ λ _M ; beam III reaches the target surface of area array detector III through the transmission prism, and obtain multispectral video images covering the working band range of λ _S ~ λ _M.

The beneficial effects of the present invention are:

1. The present invention has a wider working band range.

The invention divides the incident broadband beam into two separate working bands through the light splitting component, and uses two mosaic pixel-coated video multi-spectral area detectors to receive them at the same time, and can obtain multi-spectral images in the range of 450nm-980nm working bands at one time. .

2. The present invention has more spectral segments.

The invention divides the incident broadband beam into two separate working bands through the light splitting component, and uses two mosaic pixel-coated video multi-spectral area detectors to receive them at the same time, so it has more spectrum segments. A multispectral image of 41 bands was obtained.

3. The present invention has higher imaging resolution.

The invention divides the incident light beam into two parts according to a certain ratio through the beam splitting component in the optical path of the system, and one part of the light beam, namely the light beam I, reaches the target surface I of the panchromatic photosensitive detector with high image resolution. The resolution image adopts the image reconstruction algorithm to realize the reconstruction of the high image resolution of the mosaic pixel coating video multi-spectral area array detectors II and III, and finally a high-resolution multi-spectral image can be obtained.

4. The present invention adopts a common-aperture imaging optical system, that is, shares a set of imaging optical systems, and realizes light splitting through a cemented prism assembly located in its outgoing light path. Compared with the technical solution of multi-lens, it has a more compact volume and light structure.

5. The present invention adopts a set of wide-band video spectrum imaging system, which can simultaneously obtain a full-color high-resolution image and video multi-spectral images covering two different working band ranges.

Description of drawings

Fig. 1 is a schematic diagram of the optical path of the broadband video spectrum imaging system of the present invention;

The reference signs in the figure are: 1-front imaging optical system, 2-glued prism assembly, 21-first secondary reflection prism, 22-second secondary reflection prism, 23-transmission prism, 3-plane array Detector Ⅰ target surface, 4-area array detector Ⅱ target surface, 5-area array detector Ⅲ target surface;

Fig. 2 is a schematic diagram of the target surface of the area array detector II in the embodiment;

Fig. 3 is a schematic diagram of the target surface of the area array detector III in the embodiment.

Detailed ways

In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation modes of the present invention will be described in detail below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present invention, not all of them. Example. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in the art without creative efforts shall fall within the protection scope of the present invention.

In the following description, a lot of specific details are set forth in order to fully understand the present invention, but the present invention can also be implemented in other ways different from those described here, and those skilled in the art can do it without departing from the meaning of the present invention. By analogy, the present invention is therefore not limited to the specific examples disclosed below.

Second, "one embodiment" or "an embodiment" referred to herein refers to a specific feature, structure or characteristic that may be included in at least one implementation of the present invention. "In one embodiment" appearing in different places in this specification does not all refer to the same embodiment, nor is it a separate or selective embodiment that is mutually exclusive with other embodiments.

Secondly, the present invention is described in detail in conjunction with schematic diagrams. When describing the embodiments of the present invention in detail, for the convenience of explanation, the cross-sectional view showing the structure of the device will not be partially enlarged according to the general scale, and the schematic diagram is only an example, and it should not be used here. Limit the scope of protection of the present invention. In addition, the three-dimensional space dimensions of length, width and depth should be included in actual production.

At the same time, in the description of the present invention, it should be noted that the term "first or second" is only used for the purpose of description, and should not be understood as indicating or implying relative importance.

The wide-spectrum high-resolution video spectrum imaging system of the present invention includes a pre-imaging optical system 1 and a light splitting assembly arranged in sequence along the optical path, and also includes an area array detector 1 and an area array detector respectively located in the three-way outgoing light paths of the light splitting assembly. II and area array detector III. The front imaging optical system 1 is used to image the target, and can be a transmission optical path structure, a total reflection optical path structure or a reentrant optical path structure; it can be a camera system, a microscope system and a telescopic system. The beam splitting component is used to split the incident beam to obtain three beams with different wavelength ranges, define beam I with the beam range of λ _S ～λ _L , and define beam II with the beam range of λ _S ～λ _M ; Define the beam with a wavelength range of λ _M ~ λ _L as beam III; where λ _S < λ _M < λ _L , the wavelength range of the incident beam is the same as that of beam I; it can be seen from Figure 1 that the splitting component can be Of course, in other embodiments, the cemented prism assembly 2 may also adopt other light splitting structures. The cemented prism assembly 2 comprises a first secondary reflection prism 21, a second secondary reflection prism 22 and a transmission prism 23; the AC face of the first secondary reflection prism 21 and the DE surface of the second secondary reflection prism 22 Gluing, the EF surface of the second secondary reflection prism 22 is glued with the GH surface of the transmission prism 23; the AC surface of the first secondary reflection prism 21 is coated with a spectroscopic film; the EF surface of the second secondary reflection prism 22 Dichroic film is coated on the top; the AB surface of the first secondary reflection prism 21 is used as the incident surface, the BC surface of the first secondary reflection prism 21 is used as the outgoing surface of the light beam I, and the DF of the second secondary reflection prism 22 The surface KP of the transmissive prism 23 serves as the exit surface of the light beam II, and the KP surface of the transmissive prism 23 serves as the exit surface of the light beam III. The working band range of the area array detector I is λ _S ~ λ _L , and the target surface 3 of the area array detector I is a high-resolution wide-band panchromatic photosensitive detector target, which is placed in the exit light path of the first secondary reflective prism 21 Among them, it is used to receive the light beam I to obtain full-color high-resolution images; the working band range of the area array detector II is λ _S ~ λ _M , and the target surface 4 of the area array detector II is a mosaic pixel coated video imaging detector The target surface is placed in the outgoing optical path of the second secondary reflecting prism 22, and is used to receive the light beam II to obtain video multispectral images covering the working band range of λ _S ~ λ _M ; the working band range of the area array detector III is λ _M ～ λ _L , the target surface of the area array detector III is the mosaic pixel coating video imaging detector target surface, placed in the outgoing light path of the transmission prism 23, used to receive the light beam III, and obtain the working band covering λ _M ～ λ _L Range of video multispectral images.

The incident light beam with a working wavelength range of λ _S ~ λ _L reaches the first secondary reflection prism 21 through the pre-imaging optical system 1, passes through the spectroscopic film on the AC surface of the first secondary reflection prism 21, and divides the incident light beam by a certain amount. The light splitting ratio is divided into two parts of light beams, wherein a part of the light beam, that is, light beam I reaches the AB surface of the first secondary reflection prism 21, and then emerges from the BC surface through the reflection of the AB surface to reach the target surface of the area array detector I, and obtains a panchromatic height resolution image; the other part of the light beam reaches the EF surface of the second secondary reflection prism 22, and the light beam with the working wavelength range of λ _S ~ λ _L is divided into the light beam with the working wave band range of λ _S ~ λ through the dichroic film on it. Beam II and beam III of _M and λ _M ~ λ _L , wherein the beam II is reflected by the DE surface of the second secondary reflection prism 22, and emerges from the DF surface of the second secondary reflection prism 22 to reach the area detector II Target surface 4, to obtain video multispectral images covering the working band range of λ _S ~ λ _M ; beam III reaches the target surface 5 of the area array detector III through the transmission prism 23, and obtain video multispectral images covering the working band range of λ _S ~ λ _M image.

Due to the mosaic pixel coating technology, the target surface 4 of the area array detector II and the target surface 5 of the area array detector III are multispectral images covering a wide range of working bands, but the image resolution has a certain loss. However, the image received by the target surface 3 of the area array detector I is a panchromatic high-resolution image, and there is no loss in imaging resolution, so the panchromatic high-resolution image can be obtained by using the area array detector I. Compared with the area array detector II High-resolution reconstruction of the multispectral images obtained separately with the area array detector III to obtain high-resolution multispectral image data.

Example

This embodiment discloses a video spectrum synthesis system covering visible and near-infrared bands, and the specific implementation methods are as follows:

The working wavelength range of the incident light beam is 450nm-980nm, covering the visible and near-infrared bands. The cemented prism assembly 2 is reached through the front imaging optical system 1 . The splitting ratio of the splitting film coated on the AC surface of the first secondary reflecting prism 21 is 3:7, that is, the reflection is 30%, and the transmission is 70%. The splitting ratio is not limited to this ratio, and can be adjusted according to the actual situation. Reflect 30% of the incident beam energy to reach the AB surface of the first secondary reflection prism 21, and then exit from the BC surface through the reflection of the AB surface to reach the target surface 3 of the area array detector I to obtain a panchromatic high-resolution image; 70% of the incident beam energy reaches the EF surface of the second secondary reflection prism 22, and the dichroic film coated on the EF surface of the second secondary reflection prism 22 divides the incident beam wavelength range 450nm-980nm into 450nm-600nm and 690nm -980nm two bands range, the color separation band is not limited to this band division method, it can be adjusted according to the actual situation. Among them, the light beam in the 450nm-600nm band range is reflected by the DE surface of the second secondary reflection prism 22, exits from the DF surface, and reaches the target surface 4 of the 16-spectrum mosaic pixel coated area array detector II, to obtain the 450nm-600nm working waveband range The 16-band multispectral image. The schematic diagram of the 16-band mosaic pixel coated area array detector II target surface 4 is shown in Figure 2, in which 4×4 pixels form a group, and the central wavelengths are 450nm, 460nm, 470nm, 480nm, 490nm, 500nm, 510nm, 520nm, 530nm, 540nm, 550nm, 560nm, 570nm, 580nm, 590nm, 600nm, a total of 16 spectral channels, each channel corresponds to a single-spectrum image, the center wavelength position is not limited to this, can be adjusted according to the actual situation. The light beam in the 690nm-980nm band range passes through the transmission prism 23 and reaches the 25-band mosaic pixel coated area array detector III target surface 5 to obtain a 25-band multispectral image within the 690nm-980nm working band range. The schematic diagram of the 25-band mosaic pixel coated area array detector III target surface 5 is shown in Figure 3, in which 5×5 pixels form a group, and the center wavelengths are 690nm, 702nm, 714nm, 726nm, 738nm, 750nm, 762nm, 774nm, 786nm, 798nm, 810nm, 822nm, 834nm, 846nm, 858nm, 870nm, 882nm, 896nm, 908mn, 920nm, 932nm, 944nm, 956nm, 968nm, 980nm, a total of 25 spectral channels, each channel corresponds to a single-spectrum image , the position of the center wavelength is not limited to this, and can be adjusted according to actual conditions.

Extract all the positions corresponding to the pixels whose central wavelength is _λi on the target surface 4 of the area array detector II and the target surface 5 of the area array detector III, and then a single-spectrum low-resolution image with the central wavelength _λi can be obtained. The image is reconstructed with the panchromatic high-resolution image received by the target surface I of the area array detector, and the high-resolution image data of this spectral band can be obtained.

Claims (9)

1. A wide-band high-resolution video spectral imaging system, characterized by: the device comprises a front imaging optical system (1), a beam splitting component, an area array detector I, an area array detector II and an area array detector III;

the front-end imaging optical system (1) is used for imaging a target;

the beam splitting component is arranged between the front imaging optical system (1) and each area array detector and is used for splitting an incident beam to obtain three beams with different wave band ranges, and the wave band range is lambda _S ～λ _L Defining a beam I with a band of lambda _S ～λ _M Is defined as beam II; with a band of lambda _M ～λ _L Is defined as beam III; wherein lambda is _S ＜λ _M ＜λ _L The method comprises the steps of carrying out a first treatment on the surface of the The wave band range of the incident light beam is the same as that of the light beam I;

the light splitting component is a glued prism component (2) and comprises a first secondary reflection prism (21), a second secondary reflection prism (22) and a transmission prism (23);

the AC surface of the first secondary reflection prism (21) is glued with the DE surface of the second secondary reflection prism (22), and the EF surface of the second secondary reflection prism (22) is glued with the GH surface of the transmission prism (23); an AC surface of the first secondary reflection prism (21) is plated with a light splitting film; a color separation film is plated on the EF surface of the second secondary reflection prism (22);

the AB surface of the first secondary reflection prism (21) is used as an incident surface, the BC surface of the first secondary reflection prism (21) is used as an emergent surface of a light beam I, the DF surface of the second secondary reflection prism (22) is used as an emergent surface of a light beam II, and the PK surface of the transmission prism (23) is used as an emergent surface of a light beam III;

the working band range of the area array detector I is lambda _S ～λ _L For receiving the light beam I to obtain full-color high-resolution image;

the working band range of the area array detector II is lambda _S ～λ _M For receiving the light beam II, obtaining a coverage lambda _S ～λ _M Video multispectral images of the working band range;

the working band range of the area array detector III is lambda _M ～λ _L For receiving light beam III, obtaining coverage lambda _M ～λ _L Video multispectral image of the operating band range.

2. The wide-band high-resolution video spectral imaging system of claim 1, wherein: the working band range is lambda _S ～λ _L The incident light beam is divided into two parts of light beams according to a certain light splitting ratio through a light splitting film on an AC surface of the first secondary reflecting prism (21) when reaching the first secondary reflecting prism (21) through the front imaging optical system (1), wherein one part of light beams, namely light beam I, reaches an AB surface of the first secondary reflecting prism (21), and then exits from the BC surface to reach a target surface of an area array detector I through reflection of the AB surface, so that a full-color high-resolution image is obtained; the other part of the light beam reaches EF face of the second secondary reflecting prism (22) and the working band range is lambda by the color separation film _S ～λ _L Is divided into an operating band range lambda _S ～λ _M And lambda (lambda) _M ～λ _L Wherein the light beam II is reflected by the DE surface of the second secondary reflection prism (22) and is emitted from the DF surface of the second secondary reflection prism (22) toReaching the target surface (4) of the area array detector II to obtain coverage lambda _S ～λ _M Video multispectral images of the working band range; the light beam III reaches the target surface (5) of the area array detector III through a transmission prism (23) to obtain a coverage lambda _S ～λ _M Video multispectral image of the operating band range.

3. The wide-band high-resolution video spectral imaging system of claim 2, wherein: the front imaging optical system (1) is of a transmission type optical path structure, a total reflection type optical path structure or a foldback type optical path structure.

4. The wide-band high-resolution video spectral imaging system of claim 3, wherein: the front imaging optical system (1) is a photographing system, a microscopic system or a telescopic system.

5. The wide-band high-resolution video spectral imaging system according to any one of claims 1-4, wherein: the target surface (3) of the area array detector I is a high-resolution broadband full-color photosensitive detector target surface.

6. The wide-band high-resolution video spectral imaging system of claim 5, wherein: the target surface (4) of the area array detector II and the target surface (5) of the area array detector III are both mosaic pixel film coating video spectrum imaging detector target surfaces.

7. The wide-spectrum high-resolution video spectrum imaging method is based on a wide-spectrum high-resolution video spectrum imaging system and is characterized by comprising the following steps of:

step 1, obtaining full-color high-resolution image and covering lambda based on a wide-spectrum high-resolution video spectrum imaging system _S ～λ _M Video multispectral image of working band range and coverage lambda _M ～λ _L Video multispectral images of the working band range;

step 2, covering lambda with panchromatic high-resolution image pairs _S ～λ _M Video multi-band range of operationSpectral image and overlay lambda _M ～λ _L And carrying out high-resolution reconstruction on the video multispectral image in the working band range to obtain high-resolution multispectral image data.

8. The method for imaging a wide-band high-resolution video spectrum according to claim 7, wherein step 2 specifically comprises:

step 2.1, extracting the coverage lambda _S ～λ _M Video multispectral image of working band range and coverage lambda _M ～λ _L Each single spectral band of image data in the video multispectral image of the operating band range:

extracting the center wavelength lambda of the area array detector II target surface 4 and the area array detector III target surface 5 respectively _i Corresponding to the picture elements of (1) to obtain a center wavelength lambda _i Is a single-band low-resolution image of (1);

and 2.2, reconstructing the low-resolution image data of each single spectrum segment with the full-color high-resolution image to obtain the high-resolution image data of the spectrum segment.

9. The method for imaging a wide-spectrum high-resolution video spectrum according to claim 8, wherein step 1 specifically comprises: the working band range is lambda _S ～λ _L The incident light beam is divided into two parts of light beams according to a certain light splitting ratio through a light splitting film on an AC surface of the first secondary reflecting prism (21) when reaching the first secondary reflecting prism (21) through the front imaging optical system (1), wherein one part of light beams, namely light beam I, reaches an AB surface of the first secondary reflecting prism (21), and then exits from the BC surface to reach a target surface of an area array detector I through reflection of the AB surface, so that a full-color high-resolution image is obtained; the other part of the light beam reaches EF face of the second secondary reflecting prism (22) and the working band range is lambda by the color separation film _S ～λ _L Is divided into an operating band range lambda _S ～λ _M And lambda (lambda) _M ～λ _L Wherein the light beam II is reflected by the DE surface of the second secondary reflection prism (22) and exits from the DF surface of the second secondary reflection prism (22) to reach the surfaceThe array detector II target surface (4) is covered with lambda _S ～λ _M Video multispectral images of the working band range; the light beam III reaches the target surface (5) of the area array detector III through a transmission prism (23) to obtain a coverage lambda _S ～λ _M Video multispectral image of the operating band range.