CN211504402U

CN211504402U - Broadband hyperspectral camera based on gradual change thin film optical filter

Info

Publication number: CN211504402U
Application number: CN202020472164.5U
Authority: CN
Inventors: 刘业林; 陈兴海; 黄智辉; 张宏宇; 陈海霞; 黄宇; 康建梅
Original assignee: Sichuan Dualix Spectral Imaging Technology Co ltd
Current assignee: Jiangsu Shuangli Hepu Technology Co.,Ltd.
Priority date: 2020-04-02
Filing date: 2020-04-02
Publication date: 2020-09-15
Anticipated expiration: 2030-04-02

Abstract

The utility model relates to a high spectral camera's technical field specifically is a broadband high spectral camera based on gradual change film filter for mutual interference between the partial wave band of the high spectral camera based on gradual change film filter formula among the solution prior art, thereby the problem of the spectral signal distortion that can cause the collection. The utility model discloses an interconnect's camera body and imaging lens, this internal detector chip of installing of camera, the last gradual change film of having plated of detector chip, it partly ends the light filter to have plated the semi-permeable on the surface of gradual change film. The utility model discloses in through directly plating half cut-off filter with half passing through on the detector chip that has plated the gradual change film, make half passing through half cut-off filter and detector chip be in the same place, between the two there is not the interval to the reduction incident light that can be very big is through the optical interference who causes between half passing through half cut-off filter and detector chip in proper order, and then can reduce spectral signal's distortion phenomenon.

Description

Broadband hyperspectral camera based on gradual change thin film optical filter

Technical Field

The utility model relates to a high spectral camera's technical field, more specifically relate to a broadband high spectral camera based on gradual change film filter.

Background

The development of imaging technology goes through approximately 4 stages, the first stage being the grayscale image stage, i.e. an image with only up to 256 grays; the second phase is a color image phase consisting of three specific wavelengths: red, green and blue create an image in the visible region; a third stage, namely a multispectral image stage, wherein a multispectral system consisting of optical filters with specific wave bands can obtain multispectral images under the wave bands, and the multispectral images obtain more spectral information than RGB images; the fourth stage is a hyperspectral imaging stage, and the fourth stage is the hyperspectral imaging stage and has the greatest characteristics of continuous spectrum, more wave bands and more extracted feature spectra with guaranteed hyperspectral resolution.

The hyperspectral imaging is a comprehensive technology integrating a detector technology, a precise optical machine, weak signal detection, a computer technology and an information processing technology, is a multidimensional information acquisition technology combining an imaging technology and a spectrum technology, simultaneously detects two-dimensional geometric space and one-dimensional spectrum information of a target, and acquires continuous and narrow-band image data with high spectral resolution.

The hyperspectral imaging in the prior art is mainly based on filter imaging, and for example, a typical LCTF type hyperspectral imager generally consists of five parts: objective, adjustable light filter of liquid crystal, relay imaging optical system, camera and control system, its principle is: the method has the advantages that a high-resolution high-spectrum image can be obtained by matching a high-resolution camera, and the defects of low light transmission efficiency, low spectrum resolution, few spectrum channels and high cost are overcome.

The hyperspectral imaging is also a push-broom type imaging technology based on a grating spectral imaging spectrometer, and the structure of the hyperspectral imaging is composed of three parts: the principle of the device is that a line of a two-dimensional object is imaged through the imaging lens and passes through a front slit of the spectrometer, and then the light becomes parallel light in the direction vertical to the slit after passing through a group of lenses; the parallel light is dispersed in the direction vertical to the slit through a transmission grating in the spectrometer and is changed into monochromatic light which is spread along with the wavelength in the direction vertical to the slit; the monochromatic light spread along the direction vertical to the slit is imaged on an area array detector through the last group of lenses of the spectrometer. Its advantages are high spectral resolution, more channels, high diffraction efficiency of raster, and high cost.

The hyperspectral imaging utilizes a high-sensitivity CCD chip or an SCMOS chip as a substrate, and the technical means of respectively plating filter films with different wave bands on the CCD chip or the SCOMS chip are widely applied, in order to overcome the defects of the push-broom type imaging technology based on filter imaging and grating spectroscopic imaging spectrometer, the hyperspectral imaging technology plated with the gradual change film optical filter is provided, the structure plated with the gradual change film optical filter is simpler, the size is smaller, the cost is lower, and the hyperspectral imaging technology is one of ideal choices for popularization and application of hyperspectral technology.

In the prior art, a hyperspectral camera based on a gradient film adopts a wedge-shaped film plated on an area array detector chip based on a Fabry-Perot interference principle, so that the transmission wavelength is continuously and gradually changed, the gradient film-plated camera does not detect response at a 900nm position for short-wavelength light such as 450nm wavelength light, and light with opposite long wavelength such as 900nm light has obvious response at the 450nm position and weak response at a 600nm position, and is negligible, namely, the position of a thin film optical filter with short wavelength can also transmit light with double wavelength, so that the acquired spectral signal is distorted.

In summary, in the prior art, the wave bands of the hyperspectral camera based on the gradually-thinned film filter interfere with each other, so that the acquired spectral signals may be distorted. Therefore, there is a need for a hyperspectral camera based on a graded thin film filter that can solve the above technical problems.

SUMMERY OF THE UTILITY MODEL

Based on above problem, the utility model provides a broadband hyperspectral camera based on gradual change film filter for mutual interference between the partial wave band of solving among the prior art hyperspectral camera based on gradual change film filter formula, thereby the problem of the spectral signal distortion that probably causes the collection. The utility model discloses in through directly plating half cut-off filter with half passing through on the detector chip that has plated the gradual change film, make half passing through half cut-off filter and detector chip be in the same place, between the two there is not the interval to the reduction incident light that can be very big is through the optical interference who causes between half passing through half cut-off filter and detector chip in proper order, and then can reduce spectral signal's distortion phenomenon.

The utility model discloses a realize above-mentioned purpose and specifically adopt following technical scheme:

the hyperspectral camera comprises a camera body and an imaging lens which are connected with each other, wherein a detector chip is installed in the camera body, a gradient film is plated on the detector chip, and a semi-permeable semi-cut-off filter is plated on the outer surface of the gradient film.

In a preferred embodiment, the semi-transparent and semi-cut-off filter includes an infrared cut-off film and a set of transmission films.

In a preferred embodiment, the transparent film group includes a visible light cut film or a full-transparent film.

The utility model has the advantages that:

(1) the utility model discloses in through directly plating half cut-off filter with half passing through on the detector chip that has plated the gradual change film, make half passing through half cut-off filter and detector chip be in the same place, between the two there is not the interval to the reduction incident light that can be very big is through the optical interference who causes between half passing through half cut-off filter and detector chip in proper order, and then can reduce spectral signal's distortion phenomenon.

(2) The utility model discloses well semi-permeable half cut-off filter includes that infrared is by the membrane and is seen through the membrane group, sees through the membrane group including visible light by the membrane or pass through the membrane entirely, directly plates on the chip and can improve logical light efficiency as far as by the membrane, assurance imaging quality that can be better

(3) The utility model discloses in high spectrum camera based on gradual change coating film filter formula can rely on the development of modern detector technique to select the detector of better, higher sensitivity, higher pixel as detecting element, simultaneously along with coating film technique's development, can select suitable, economic coating film camera so that can acquire the image and the spectral information of target according to the application demand.

(4) The utility model discloses in can expand the spectrum test range based on gradual change film filter formula hyperspectral camera, reduce because the influence to image, spectrum that multistage printing opacity problem arouses, ensure that the image of each collection all has the effect that highly uniform spatial structure overall arrangement, accurate spectral distribution and image tone match completely.

Drawings

FIG. 1 is a schematic view of the front structure of the present invention;

FIG. 2 is a schematic cross-sectional view taken along line A-A of FIG. 1 according to the present invention;

FIG. 3 is an enlarged schematic view of the present invention at B in FIG. 2;

FIG. 4 is a schematic view of the semi-permeable and semi-cut-off filter of the present invention;

reference numerals: the device comprises a camera body 1, a detector chip 2, a gradient film 3, a semi-transparent semi-cut-off filter 4, a visible light cut-off film 41, an infrared cut-off film 42 and an imaging lens 5.

Detailed Description

For a better understanding of the present invention, the present invention will be described in further detail with reference to the accompanying drawings and the following embodiments.

Example (b):

as shown in fig. 1-4, a hyperspectral camera based on a gradient thin-film optical filter comprises a camera body 1 and an imaging lens 5 which are connected with each other, wherein a detector chip 2 is installed in the camera body 1, a gradient thin film 3 is plated on the detector chip 2, and a semi-permeable semi-cut-off optical filter 4 is plated on the outer surface of the gradient thin film 3. The semi-transparent and semi-cut-off filter 4 includes an infrared cut-off film 42 and a transmission film group, and the transmission film group includes a visible light cut-off film 41 or a full transmission film.

The working principle is as follows: the detection chip is plated with a gradient film 3, the range of the gradient film 3 is expanded, the gradient film covers a 400nm-1000nm wave band, the gradient film 3 is plated with a semi-permeable semi-cut-off filter 4, and the semi-permeable semi-cut-off filter 4 is divided into two parts: the purpose of half plating the infrared cut-off film 42 is to cut off the infrared spectrum, the other half is the visible light cut-off film 41 or the full-transmission film, the full-transmission film is not processed, all the entering light information is allowed to pass through, the multi-level light transmission effect is solved, the visible light cut-off film 41 can avoid the influence of the 400-plus-500-nm waveband light information on the acquisition of the 800-plus-1000-nm waveband data, and the experiment verifies that the influence of the 400-plus-500-nm waveband light information on the acquisition of the 800-plus-1000-nm waveband data is very small.

In short, the semi-permeable and semi-cut-off filter 4 is directly plated on the detector chip 2 plated with the gradient film 3, so that the semi-permeable and semi-cut-off filter 4 and the detector chip 2 are combined together without a gap, and thus optical interference caused when incident light sequentially passes through the semi-permeable and semi-cut-off filter 4 and the detector chip 2 can be greatly reduced, and further the distortion phenomenon of a spectrum signal can be reduced.

The embodiment of the present invention is the above. The specific parameters in the above embodiments and examples are only for the purpose of clearly showing the verification process of the present invention, and are not used to limit the protection scope of the present invention, which is still subject to the claims, and all the equivalent structural changes made by using the contents of the specification and drawings of the present invention should be included in the protection scope of the present invention.

Claims

1. The utility model provides a hyperspectral camera based on gradual change film filter, includes interconnect's camera body (1) and imaging lens (5), its characterized in that: the camera is characterized in that a detector chip (2) is installed in the camera body (1), a gradual change film (3) is plated on the detector chip (2), and a semi-permeable semi-cut-off filter (4) is plated on the outer surface of the gradual change film (3).

2. The hyperspectral camera based on the gradual change thin film filter of claim 1, wherein: the semi-permeable and semi-cut-off filter (4) comprises an infrared cut-off film (42) and a transmission film group.

3. The hyperspectral camera based on the gradual change thin film filter of claim 2, wherein: the transmissive film group includes a visible light cut-off film (41) or a full-transmissive film.