CN110264860A - A kind of multispectral image camouflage method based on multimembrane system array - Google Patents

Abstract

The invention discloses a multi-spectral image camouflage method based on a multi-film array, and specifically relates to the technical field of image information hiding and reading. In the present invention, multiple images can be accumulated on the same surface by using different film stack structures, and the notch filter characteristics of the multi-layer film system are used to encode the spectrum, so that multiple images can be hidden in the same coding plane, and the encrypted information capacity can be increased. During the stacking process of the film system, the film layers in one cycle use - - For coating, when the cut-off center wavelength is arbitrary , the corresponding period is n. When the image is displayed, when the light source of the corresponding wavelength is used to irradiate, the film layer at the corresponding point on the sample that constitutes the image information has almost zero transmittance to the incident light, and the reflectivity is very high, so the observation of the light-transmitting sample can be seen. Wavelength image information.

Description

A Multispectral Image Camouflage Method Based on Multifilm Array

technical field

The invention relates to the technical field of image information hiding and reading, in particular to a multi-spectral image camouflage method based on a multi-film array.

Background technique

With the advancement and update of science and technology and the increasingly complex working environment, the technical requirements for image information hiding and reading technology continue to increase. Optical encryption technology has the advantages of high resolution, no multipath effect, good concealment, light weight, and small size.

In the prior art, the article "Hiding multi-level multi-color images interahertz metasurfaces" published in December 2016 mentioned the use of resonant structure arrays, using the characteristics of different structures and different electrical conductivities, and using terahertz frequency to make the lens The resonant absorption depths in are different, thus presenting picture information. However, due to the one-to-one correspondence between its metasurface structure and image information, multiple images cannot be presented on the same surface. In the article "High-resolution grayscal image hidden in a laser beam" published in December 2017, linearly polarized light is used to directly illuminate a set of linearly polarized devices corresponding to the content of the picture, and the image is presented with different intensity of reflected light corresponding to each point information, but there is also the problem that only one picture can be hidden and the amount of information is small.

Contents of the invention

The purpose of the present invention is to address the above-mentioned deficiencies, and propose a multi-spectral image camouflage method based on a multi-film array, which encodes the spectrum, realizes multi-image hiding in the same coding plane, and increases the encrypted information capacity of the narrow-band rectangular hole Notch filter.

The present invention specifically adopts the following technical solutions:

A multi-spectral image camouflage method based on a multi-film array, including a multi-layer film system, in the stacking process of the multi-layer film system, the film layers in one cycle use - - For coating, when the cut-off center wavelength is When , the corresponding period is n; when the coating is superimposed on the same pixel point, the film layer with different thickness d is plated on the same pixel point to achieve different center wavelength notches at the same pixel point to change the center wavelength of the notch.

Preferably, the filters are encoded.

Preferably, in the process of encoding the optical filter, the encryption plate is encoded, and the cut-off center wavelength is selected as Point, add the corresponding wavelength filter between the light source and the encryption board. The position of the encryption board is the coating position selected according to the graphics requirements, which is used to form the notch phenomenon of the graphics content to display the image information at the corresponding wavelength.

Preferably, in the process of encoding the optical filter, because when the white light source directly illuminates the encryption plate, the combination pattern of multiple images superimposed together can be seen through the encryption plate, and the image information cannot be read at this time.

Preferably, when the image is displayed, when the light source of the corresponding wavelength is used to illuminate, the film layer on the corresponding point constituting the image information on the sample has a near-zero transmittance to the incident light, and the reflectivity is very high, so the observation of the light-transmitting sample The image information corresponding to the wavelength can be seen.

The present invention has following beneficial effects:

In the process of encoding the optical filter, encode the encryption plate, and select the cut-off center wavelength as Point, by adding the corresponding wavelength filter between the light source and the encryption board, the coating position of the encryption board in the graphic needs to be selected in the picture is used to form the notch phenomenon in the picture content to display the image information at the corresponding wavelength, when the image is displayed , when the corresponding wavelength light source is used, the film layer at the corresponding point on the sample that constitutes the image information has almost zero transmittance to the incident light, and the reflectivity is very high, so the image information of the corresponding wavelength can be seen when observing the light-transmitting sample , multiple images can be accumulated on the same surface by utilizing the different membrane stack structures.

Description of drawings

Figure 1 is a schematic diagram of the filter notch;

Figure 2 is the wave-limiting graph under red light irradiation;

Figure 3 is the wave-limiting graph under the irradiation of green light;

Figure 4 is the wave-limiting graph under blue light irradiation;

Fig. 5 is a cross-sectional view of the wave-limiting film layer within a longitudinal period of the red light wavelength;

Fig. 6 is a cross-sectional view of the wave-limiting film layer within a longitudinal period of the green light wavelength;

Figure 7 is a cross-sectional view of the wave-limiting film layer within a longitudinal period of the blue light wavelength;

Fig. 8 is the light intensity curve after the light source passes through the red light filter;

Fig. 9 is the light intensity curve after the light source passes through the green light filter;

Figure 10 is the light intensity curve after the light source passes through the blue light filter;

Figure 11 is the wave-limiting graph under the irradiation of red and blue light;

Figure 12 is the wave-limiting pattern under blue-green light irradiation;

Figure 13 is the wave-limiting graph under the irradiation of red and green light;

Figure 14 is the wave-limiting pattern under the irradiation of red, blue and green three-color light;

Figure 15 is a cross-sectional view of the wave-limiting film layer within a longitudinal period of red and blue light wavelengths;

Figure 16 is a cross-sectional view of the wave-limiting film layer within a longitudinal period of the blue-green light wavelength;

Figure 17 is a cross-sectional view of the wave-limiting film layer within a longitudinal period of red and green light wavelengths;

Fig. 18 is a cross-sectional view of the wave-limiting film layer of red, blue and green light wavelengths;

Fig. 19 is the light intensity curve after the light source passes through the blue-green light filter;

Fig. 20 is the light intensity curve after the light source passes through the blue-green light filter;

Fig. 21 is the light intensity curve after the light source passes through the red and green light filter;

Fig. 22 is the light intensity curve after the light source passes through the red, blue and green three-color light filter;

Figure 23 is a schematic diagram of sample coating.

Detailed ways

The specific embodiment of the present invention will be further described below in conjunction with accompanying drawing and specific embodiment:

As shown in Figure 1, a multi-spectral image camouflage method based on a multi-film array includes a multi-layer film system. During the stacking process of the multi-layer film system, the film layers in one cycle use - - For coating, when the cut-off center wavelength is When , the corresponding period is n; when there are multiple cut-off center wavelengths, the cut-off center wavelengths are , , , corresponding to the three images as shown in Fig. 2, Fig. 3, and Fig. 4; when superimposing the coating on the same pixel point, the film layer with different thickness d is plated on the same pixel point, so as to realize the trapping of different central wavelengths at the same pixel point wave to change the center wavelength of the notch. As shown in Figure 5, Figure 6, and Figure 7, the corresponding wavelength reflectance images are shown in Figure 8, Figure 9 and Figure 10; and the film systems with different cut-off center wavelengths are superimposed on each other without affecting each other, and the displayed images are shown in Figure 11 and Figure 10. 12. As shown in Figure 13 and Figure 14, the film structure corresponding to each point is shown in Figure 15, Figure 16, Figure 17, and Figure 18, and the corresponding wavelength-reflectance images are shown in Figure 19, Figure 20, Figure 21, and Figure 22.

Encode the filter, in the process of encoding the filter, encode the encryption plate, and select the cut-off center wavelength as Point, add the corresponding wavelength filter between the light source and the encryption board. The position of the encryption board is the coating position selected according to the graphics requirements, which is used to form the notch phenomenon of the graphics content to display the image information at the corresponding wavelength. In the process of encoding the optical filter, because when the white light source directly illuminates the encryption plate, the combination pattern of multiple images superimposed together can be seen through the encryption plate, and the image information cannot be read at this time.

As shown in Figure 23, The corresponding area is the notch center wavelength of pixels, The corresponding area is the notch center wavelength of pixels, The corresponding area is the notch center wavelength is of pixels, , The corresponding area is the center wavelength of the notch, respectively , , , the corresponding area is the center wavelength of the notch, respectively , , when white light is irradiated, since white light contains all wavelengths of colored light, if the transmitted information is wavelength content, the image information at a specific wavelength is hidden at this time.

When the image is displayed, when the light source of the corresponding wavelength is used to irradiate, the film layer at the corresponding point on the sample that constitutes the image information has almost zero transmittance to the incident light, and the reflectivity is very high, so the observation of the light-transmitting sample can be seen. Wavelength image information.

Of course, the above descriptions are not intended to limit the present invention, and the present invention is not limited to the above examples. Changes, modifications, additions or replacements made by those skilled in the art within the scope of the present invention shall also belong to the present invention. protection scope of the invention.

Claims (5)

1. a kind of multispectral image camouflage method based on multimembrane system array, is characterized in that comprising assembly of thin films, the multilayer film It ties up in stacking process, the film layer in a cycle uses--Plated film is carried out, when cut-off central wavelength is When, the corresponding period is n；When being superimposed plated film on same pixel, in the film layer of same pixel plating different-thickness d, realize Same pixel is to different central wavelength traps, to change trap central wavelength.

2. a kind of multispectral image camouflage method based on multimembrane system array as described in claim 1, which is characterized in that filter Wave plate is encoded.

3. a kind of multispectral image camouflage method based on multimembrane system array as claimed in claim 2, which is characterized in that right During the optical filter is encoded, densifying plate is encoded, select cut central wavelength processed forPoint in light source and adds Respective wavelength filter plate is added between close plate, the position of densifying plate is the plating film location selected according to figure demand, for constituting There is trap phenomenon and shows image information under respective wavelength in graphical content.

4. a kind of multispectral image camouflage method based on multimembrane system array as claimed in claim 3, which is characterized in that right During the optical filter is encoded, due to being seen through densifying plate more when white light source is to densifying plate direct irradiation The combination pattern that width image is superimposed jointly can not read image information at this time.

5. a kind of multispectral image camouflage method based on multimembrane system array as claimed in claim 3, which is characterized in that scheming As when irradiating using corresponding wavelength light source, the film layer in the corresponding points of image information is constituted on print to incident light when showing Transmiting nearly rate is zero, and reflectivity is very high, therefore the observation of light transmission exemplar can see that the image information of corresponding wavelength.