CN217443616U - Multispectral optical filter, multispectral lens and camera device - Google Patents

Abstract

The utility model discloses a multispectral light filter, multispectral camera lens and camera device. A multispectral optical filter, comprising: a substrate formed in a flat plate shape and having a rotational degree of freedom around a center thereof, the substrate having a plurality of filter regions through which light passes; the filter regions at least comprise a first filter region and a second filter region, wherein the first filter region and the second filter region form a narrow-band-pass filter region, the filter band range of the first filter region is 600nm to 700nm, and the filter band range of the second filter region is 750nm to 850 nm.

Description

Multispectral optical filter, multispectral lens and camera device

Technical Field

The utility model relates to a camera technical field, in particular to multispectral light filter, multispectral camera lens and a camera device.

Background

A vegetation remote sensing monitoring technology is a new technology which combines induction remote sensing and monitoring of resource management (such as resource management of trees, grasslands, soil, water, minerals, farm crops, fishes, wild animals and the like) on the earth surface through a remote sensing instrument on an artificial earth satellite. The technology is suitable for macroscopic large-area vegetation detection, has high cost and is difficult to popularize for civil use.

The unmanned aerial vehicle remote sensing detection technology is a technology for detecting vegetation at low altitude by combining an unmanned aerial vehicle and a remote sensing technology and remotely controlling and planning an unmanned aerial vehicle flying by a flight line in a wireless manner. Compared with the traditional remote sensing detection technology, the technology has the advantages of low cost, simplicity in operation and the like, and has a wide prospect in the aspect of vegetation detection in small and medium-area areas.

How to obtain the image beneficial to vegetation health condition analysis through the camera device who loads in unmanned aerial vehicle is the problem that can realize civilian vegetation detection application and await the solution urgently.

SUMMERY OF THE UTILITY MODEL

In view of the above, the present invention provides a multispectral optical filter, a multispectral lens, and an imaging device, which can obtain an image showing the health status of vegetation by providing a plurality of filter regions of different filter bands corresponding to the plant spectrum on the optical filter.

An embodiment of the utility model provides a multispectral light filter, include:

a substrate formed in a flat plate shape and having a rotational degree of freedom around a center thereof, the substrate having a plurality of filter regions through which light passes;

the filter regions at least comprise a first filter region and a second filter region, wherein the first filter region and the second filter region form a narrow-band-pass filter region, the filter band range of the first filter region is 600nm to 700nm, and the filter band range of the second filter region is 750nm to 850 nm.

In one embodiment, the central wavelength of the filtering wave band of the first filtering area is 650nm +/-10 nm, and the bandwidth is less than or equal to 50 nm;

the central wavelength of the filtering wave band of the second filtering area is 800nm +/-10 nm, and the bandwidth is less than or equal to 50 nm.

In one embodiment, the substrate is formed in a circular shape and has a rotational degree of freedom around a center thereof to adjust a position of the filter region on the substrate.

In one embodiment, further comprising:

and an output shaft of the driver is connected with the substrate so as to drive the substrate to rotate around the circle center of the substrate.

In one embodiment, the filtering region comprises a third filtering region and/or a fourth filtering region;

the third filtering area is a full-spectrum light-transmitting area;

the fourth filtering area is a broadband band-pass light-transmitting area, and the bandwidth of the fourth filtering area is larger than or equal to 150 nm.

In one embodiment, the fourth light-filtering region is a visible light-filtering region.

In one embodiment, the first filter region, the second filter region, the third filter region and/or the fourth filter region are disposed on the substrate at equal angular intervals;

the center of each of the first filter region, the second filter region, and the third filter region and/or the fourth filter region is spaced equidistantly from the center of the substrate.

Another embodiment of the utility model provides a multispectral camera lens, include:

a lens housing;

the lens is arranged in the lens shell, and light rays entering the inside of the lens shell are converged by the lens; and

the multispectral optical filter as described above, the light converged by the lens passes through any one of the filtering regions on the substrate,

wherein the center of the substrate is offset from the optical axis of the lens.

The utility model discloses a still another embodiment provides a camera device, include:

a control circuit;

the multispectral lens as described above, the collection object of the multispectral lens comprises plants, the multispectral lens receives the electrical signal output by the control circuit, and the substrate is rotated around the center thereof under the control of the electrical signal so as to align the center of any one of the filtering regions with the optical axis of the lens;

an image sensor that receives light passing through any one of the filtering regions to generate an image of the acquisition object corresponding to a filtering band of the filtering region.

As can be seen from the above technical solutions, the filter wavelength ranges of the first filter region and the second filter region are determined by the spectrum of the collection object. The leaves of typical plants have strong absorption to the red light band of visible light and strong reflection to the near infrared band light, which is the physical basis of vegetation detection technology. Accordingly, in the present embodiment, the multispectral filter is applied to vegetation health monitoring, and therefore its filtering band corresponds to the vegetation spectrum, specifically is set to correspond to the near-infrared band.

In order to reflect the health condition of the vegetation, the multispectral optical filter of the embodiment is provided with two filtering regions with different filtering band ranges, when light from the same collecting object is filtered by the first filtering region and the second filtering region respectively, two images with different gray levels can be formed on the photosensitive element respectively, and further the health condition of the vegetation can be analyzed by comparing the two images with different gray levels.

In this embodiment, the substrate has a rotational degree of freedom around its center to switch the position of the light filtering region by rotation to achieve selective passage of light. The corresponding filter area is aligned with the lens 2 by rotating the substrate 10 to obtain a filtered image corresponding to the filter area.

Drawings

The following drawings are only schematic illustrations and explanations of the present invention, and do not limit the scope of the present invention.

Fig. 1 is a schematic diagram of the structure of the multispectral optical filter of the present invention.

Fig. 2 is a schematic structural diagram of the multispectral lens of the present invention.

Fig. 3 is a graph of spectral transmittance of the first filtered region of fig. 1.

Fig. 4 is a graph of spectral transmittance of the second filtered region of fig. 1.

Fig. 5 is a graph of spectral transmittance of the third filtered region of fig. 1.

Fig. 6 is a graph of spectral transmittance of the fourth filtered region of fig. 1.

Fig. 7 is a schematic structural diagram of the image pickup apparatus of the present invention.

Fig. 8a to 8c are imaging diagrams corresponding to different filter regions of the image pickup apparatus according to the present invention.

Detailed Description

In order to clearly understand the technical features, objects, and effects of the present invention, embodiments of the present invention will be described with reference to the accompanying drawings, in which like reference numerals refer to like parts in the drawings.

"exemplary" means "serving as an example, instance, or illustration" herein, and any illustration, embodiment, or steps described as "exemplary" herein should not be construed as a preferred or advantageous alternative.

For the sake of simplicity, the drawings only schematically show the parts relevant to the present invention, and do not represent the actual structure as a product. In addition, in order to make the drawings concise and understandable, components having the same structure or function in some of the drawings are only schematically illustrated or only labeled.

In order to solve the problem that the healthy device of vegetation is difficult to realize civilian monitoring among the prior art, the utility model provides a multispectral light filter, multispectral camera lens and a camera device, its filter zone through set up a plurality of different filter wave bands corresponding with the plant spectrum on the light filter to obtain the image that can embody vegetation health status.

Fig. 1 is a schematic structural diagram of the multispectral optical filter of the present invention. As shown in fig. 1, an embodiment of the present invention provides a multispectral optical filter 3, including:

a substrate 10, the substrate 10 being formed in a flat plate shape and having a rotational degree of freedom around a center thereof, the substrate 10 having a plurality of filter regions through which light passes;

the filter regions at least include a first filter region 21 and a second filter region 22, wherein the first filter region 21 and the second filter region 22 form a narrow-band-pass filter region, the filter wavelength range of the first filter region 21 is 600nm to 700nm, and the filter wavelength range of the second filter region 22 is 750nm to 850 nm.

The filter wavelength bands of the first filter region 21 and the second filter region 22 are determined by the spectrum of the collection target. The leaves of typical plants have strong absorption to the red light band of visible light and strong reflection to the near infrared band light, which is the physical basis of vegetation detection technology. Accordingly, in the present embodiment, the multispectral filter is applied to vegetation health monitoring, and therefore, the filtering band thereof corresponds to the vegetation spectrum, specifically, is set to correspond to the near-infrared band.

In order to reflect the health condition of the vegetation, the multispectral optical filter of this embodiment has two filtering regions with different filtering band ranges, and after the light from the same collecting object passes through the first filtering region 21 and the second filtering region 22 respectively, two images with different gray levels can be formed on the photosensitive element respectively, and further the health condition of the vegetation can be analyzed by comparing the two images with different gray levels.

In the present embodiment, the substrate 10 has a rotational degree of freedom around its center to switch the position of the light filtering region by rotation to realize selective passage of light. Fig. 2 is a schematic structural diagram of the multispectral lens of the present invention. As shown in fig. 2, in the multispectral lens, the light collected by the lens 2 is filtered by the filter region. Therefore, the substrate 10 is rotated to align the corresponding filter region with the lens 2, so as to obtain a filtered image corresponding to the filter region.

In the present embodiment, the first filter region 21 and the second filter region 22 are each formed as a narrow band-pass filter region, and the filter wavelength bands of the first filter region 21 and the second filter region 22 do not overlap. For example, the first filtering region 21 has a filtering wavelength range of 600nm to 700nm, and the second filtering region 22 has a filtering wavelength range of 750nm to 850 nm. Alternatively, as shown in FIG. 2 and FIG. 3, the center wavelength of the filtering band of the first filtering region 21 is 650nm + -10 nm, and the bandwidth is less than or equal to 50 nm; the central wavelength of the filtering wave band of the second filtering area 22 is 800nm +/-10 nm, and the bandwidth is less than or equal to 50 nm.

In a preferred embodiment, the substrate 10 is formed in a circular shape and has a rotational degree of freedom around its center to adjust the position of the filter region on the substrate 10. The circular shape allows for easy setting of the rotational position, as well as the position of the light filtering area. Wherein, the optical filter 3 may further include: and the output shaft of the driver 30 is connected with the substrate 10 to drive the substrate 10 to rotate around the center of the circle.

The driver 30 may include a driving motor and an engagement assembly for coupling an output shaft of the driving motor with the substrate 10 to convert a rotational output of the driving motor into a rotation of the substrate 10 about a center thereof. The bonding assembly may be bonded to the edge or center of the substrate 10.

For example, the engaging member may be an endless belt wound around the output shaft of the driving motor and the circular center of the substrate 10, so that the rotational output of the driving motor can directly drive the substrate 10 to rotate around the circular center thereof. Alternatively, the coupling member may be a transmission gear or a gear set that meshes with an output shaft of the driving motor and an edge of the base plate 10, respectively, to convert the rotational output of the driving motor into rotation of the base plate 10 about its center.

As shown in fig. 1, the filter region may further include a third filter region 23 and/or a fourth filter region 24; the third filtering area 23 is a full-spectrum light-transmitting area, and the fourth filtering area 24 is a broadband band-pass light-transmitting area, and the bandwidth of the broadband band-pass light-transmitting area is greater than or equal to 150 nm.

In a preferred embodiment, the fourth filter region 24 is a visible light filter region.

In order to enable the imaging device using the present embodiment to have a wider application range, such as being applicable to normal image monitoring and shooting, the optical filter of the present embodiment also provides a conventional filtering region, such as a full-spectrum light-transmitting region or an infrared filtering region. The third filter region 23 and the fourth filter region 24 may be used alternatively or in combination depending on the actual usage situation.

As can be seen from fig. 2, when the third filtering region 23 corresponds to the lens 2, the image capturing device captures visible light and near infrared light in the environment, and when the fourth filtering region 24 corresponds to the lens 2, the image capturing device captures visible light in the environment and cuts off the near infrared light.

As shown in FIG. 5 and FIG. 6, the filtering range of the third filtering region 23 is 410 to 900nm band, the average transmittance T is 90% or more, the filtering range of the fourth filtering region 24 is 410 to 550nm, the average transmittance T is 85% or more, and the average transmittance T is 0.3% or less in 680 to 900nm band.

As shown in fig. 1, the first filter region 21, the second filter region 22, and the third filter region 23 and/or the fourth filter region 24 are provided on the substrate 10 at equal angular intervals; the centers of each of the first filter region 21, the second filter region 22, and the third filter region 23 and/or the fourth filter region 24 are spaced equidistantly from the center of the substrate 10.

For example, the filter 3 includes a first filter region 21, a second filter region 22, a third filter region 23, and a fourth filter region 24, each of which is spaced apart by 90 degrees and each of which has a center located on a concentric circle with the substrate 10. When the substrate 10 of the filter 3 rotates around its center, each of the filter regions can be rotated to a fixed position, such as a position corresponding to the lens 2, by adjusting the azimuth angle.

Fig. 2 is a schematic structural diagram of the multispectral lens of the present invention. As shown in fig. 2, an embodiment of the present invention provides a multispectral lens, including:

a lens housing 1;

the lens 2 is arranged in the lens shell 1, and light rays entering the inside of the lens shell 1 are converged by the lens 2; and

as shown in fig. 1, the multispectral filter 3 is configured such that light collected by the lens 2 passes through any one of the filtering regions on the substrate 10, wherein the center of the substrate 10 is offset from the optical axis of the lens 2.

As shown in fig. 2, the central axis of the substrate 10 is parallel to the optical axis of the lens 2, and the distance between the central axis of each filter region and the central axis of the substrate 10 is equal to the distance between the center of each filter region and the central axis of the substrate.

When the multispectral filter 3 rotates, each filtering region can be located on the arc corresponding to the position of the lens 2, and the alignment between the filtering regions and the lens 2 can be realized only by controlling the rotation angle of the substrate 10.

Fig. 7 is a schematic structural diagram of the image pickup apparatus of the present invention. As shown in fig. 7, an embodiment of the present invention provides an image pickup apparatus, including:

a control circuit 4;

the multispectral lens shown in fig. 2, wherein the collection object of the multispectral lens includes a plant, the multispectral lens receives the electrical signal output by the control circuit 4, and the substrate 10 is controlled by the electrical signal to rotate around the center thereof, so that the center of any one of the filtering regions is aligned with the optical axis of the lens 2; and

and an image sensor 5, wherein the image sensor 5 receives the light passing through any one of the filtering areas to generate an image of the collecting object corresponding to the filtering band of the filtering area.

The electric signal output by the control circuit 4 may be implemented as a current signal or a voltage signal. For example, the control circuit 4 outputs a pulse signal (voltage signal), and the multispectral filter 3 in the multispectral lens receives the pulse signal and rotates the substrate 10 by a fixed angle (for example, when four filter regions are included, the angle may be 90 °) through the driver 30 to align one of the filter regions with the lens 2.

Of course, the multispectral filter 3 may be rotated continuously or intermittently, and the multispectral filter 3 may be rotated at one time, and accordingly, the image capturing apparatus only uses one shooting mode, and the multispectral filter 3 may be rotated multiple times, and accordingly, the image capturing apparatus will use a plurality of different shooting modes to obtain different captured images.

For example, the camera device of the present embodiment may have two operation modes of plant health monitoring and general video monitoring:

1. plant health monitoring mode

When the image capturing device is turned on, the control circuit 4 outputs a control electrical signal to drive the substrate 10 to rotate through the driver 30, so that the first filter region 21, the second filter region 22 and the fourth filter region 24 are respectively aligned with the lens 2 in the sequence of 24- >21- >22- >24, and the image sensor 5 respectively obtains a visible light image, an infrared 600nm image and a near-infrared 800nm image. Wherein the time for switching each filtering area to the next filter is less than or equal to 0.5s, and the residence time of each filtering area is less than or equal to 5 s.

Fig. 8a to 8c are imaging diagrams corresponding to different filter regions of the image pickup device according to the present invention. Fig. 8a is a visible light image captured by the image capturing device when the fourth filtering region 24 is in operation, the image is colored (for example only), the unhealthy tree in the upper left corner shows a dark yellow color, and the healthy tree in the periphery shows a green color, and although the unhealthy tree and the healthy tree can be distinguished from each other by the color, the limitation of the distinction is large, and on one hand, if the color of the healthy tree is yellow, erroneous judgment may be caused, and on the other hand, the healthy tree may become yellow in autumn.

Fig. 8b is an infrared 600nm image collected by the camera device when the first filtering region 21 is in operation, and the image is a gray scale image, in which the brightness of the unhealthy tree in the upper left corner is higher, and the brightness of the healthy tree in the periphery is lower.

Fig. 8c is a near-infrared 800nm image collected by the camera device when the second filtering region 22 is in operation, and the image is a gray scale image, in which the brightness of the unhealthy tree in the upper left corner is low, and the brightness of the healthy tree in the periphery is high.

Therefore, the utility model discloses a camera device has obtained three different images of shooing, then can calculate and contrasts the analysis to three pictures of figure 8 a-8 c according to camera plant health monitoring algorithm, for example the target object luminance is high in figure 8b, luminance is low in figure 8c, then can judge that the target plant is in unhealthy state; otherwise, if the brightness of the target object is low in fig. 8b and high in fig. 8c, the target plant is determined to be in a healthy state.

2. Normal video monitoring mode

When the image pickup device starts the mode, the control circuit 4 outputs a control electric signal to drive the substrate 10 to rotate through the driver 30, the fourth filtering region 24 can work in the daytime, and the image sensor obtains a visible light color image; the third filtering area 23 is operated at night, and black and white images are obtained by the image sensor by means of the near-infrared light supplement lamp, so that the video monitoring function of the common camera is realized.

The image pickup device of the embodiment can respectively collect a visible light image, a 600nm image and an 800nm image by applying the multispectral lens with the multispectral optical filter, so as to obtain image data which is beneficial to plant health condition analysis. And further comparing and analyzing the various images to obtain the health condition of the target plant. Use this camera device to carry out plant health monitoring, reducible erroneous judgement through the colour is judged, compares in current plant remote sensing technology simultaneously, and this camera device has simple to operate, easy operation, advantage that the cost is lower.

Furthermore, the image pickup device of the embodiment not only has the function of plant health monitoring, but also does not sacrifice the low-illumination performance index of a common camera because the image pickup device is provided with the visible filter and the full-transmission filter.

In this context, "a" does not mean that the number of the relevant portions of the present invention is limited to "only one", and "one" does not mean that the number of the relevant portions of the present invention "more than one" is excluded.

Unless otherwise indicated, numerical ranges herein include not only the entire range within its two endpoints, but also several sub-ranges subsumed therein.

The above list of details is only for the feasible embodiments of the present invention and is not intended to limit the scope of the present invention, and all equivalent embodiments or modifications, such as combinations, divisions or repetitions of the features, which do not depart from the technical spirit of the present invention, should be included in the scope of the present invention.

Claims (9)

1. A multispectral optical filter (3) comprising:

a substrate (10), the substrate (10) being formed in a flat plate shape and having a rotational degree of freedom around the center thereof, the substrate (10) having formed thereon a plurality of filter regions through which light passes;

the filter region at least comprises a first filter region (21) and a second filter region (22), wherein the first filter region (21) and the second filter region (22) form a narrow-band-pass filter region, the filter wavelength range of the first filter region (21) is 600nm to 700nm, and the filter wavelength range of the second filter region (22) is 750nm to 850 nm.

2. The multispectral filter (3) according to claim 1, wherein the first filtering region (21) has a filtering band with a central wavelength of 650nm ± 10nm and a bandwidth of less than or equal to 50 nm;

the central wavelength of the filtering wave band of the second filtering area (22) is 800nm +/-10 nm, and the bandwidth is less than or equal to 50 nm.

3. Multispectral filter (3) according to claim 1, wherein the substrate (10) is formed in a circular shape with a rotational freedom around its centre to adjust the position of the filtering regions on the substrate (10).

4. The multispectral filter (3) according to claim 3, further comprising:

the output shaft of the driver (30) is connected with the substrate (10) so as to drive the substrate (10) to rotate around the circle center of the substrate.

5. The multispectral filter (3) according to claim 1, wherein the filtering regions comprise a third filtering region (23) and/or a fourth filtering region (24);

wherein the third filtering area (23) is a full-spectrum light-transmitting area;

the fourth filtering area (24) is a broadband band-pass light-transmitting area, and the bandwidth of the fourth filtering area is more than or equal to 150 nm.

6. The multispectral filter (3) according to claim 5, wherein the fourth filtering region (24) is a visible filtering region.

7. The multispectral filter (3) according to claim 5, wherein the first filter region (21), the second filter region (22), and the third filter region (23) and/or the fourth filter region (24) are arranged on the substrate (10) at equal angular intervals;

the center of each of the first filter region (21), the second filter region (22), and the third filter region (23) and/or the fourth filter region (24) is spaced equidistantly from the center of the substrate (10).

8. A multispectral lens, comprising:

a lens housing (1);

the lens (2) is arranged in the lens shell (1), and light rays entering the inside of the lens shell (1) are converged by the lens (2); and

the multispectral filter (3) according to any one of claims 1 to 7, wherein light collected by the lens (2) passes through any one of the filter regions on the substrate (10),

wherein the center of the substrate (10) is arranged offset from the optical axis of the lens (2).

9. An image pickup apparatus, comprising:

a control circuit (4);

the multispectral lens of claim 8, wherein the collection object of the multispectral lens comprises a plant, the multispectral lens receives an electrical signal output by the control circuit (4), and the substrate (10) is controlled by the electrical signal to rotate around the center thereof so as to align the center of any one of the filter regions with the optical axis of the lens (2);

an image sensor (5), wherein the image sensor (5) receives the light passing through any one of the filtering areas to generate an image of the acquisition object corresponding to the filtering band of the filtering area.

Images