WO2016086720A1

WO2016086720A1 - Hyperspectral scanner

Info

Publication number: WO2016086720A1
Application number: PCT/CN2015/091846
Authority: WO
Inventors: 张立福; 张红明; 吴太夏
Original assignee: 中国科学院遥感与数字地球研究所
Priority date: 2014-12-03
Filing date: 2015-10-13
Publication date: 2016-06-09
Also published as: CN104506750A

Abstract

The present invention relates to the technical field of spectral imaging. Disclosed is a hyperspectral scanner, comprising: a spectral imaging unit for irradiating white light to an object to be scanned, conducting light splitting processing on diffusely reflected light in a current scanning line of the object to be scanned, and receiving light rays in each wave band after the light splitting processing to generate an electrical signal corresponding to the light rays in each wave band; an optoelectronic conversion unit for receiving the electrical signal, conducting analog-to-digital conversion on the electrical signal to obtain a digital signal, transmitting the digital signal to a host computer, and transmitting a drive signal to a mechanical drive unit; and the mechanical drive unit for driving, after receiving the drive signal, the spectral imaging unit to move to a position corresponding to the next scanning line of the object to be scanned. After the scanner of the present invention conducts light splitting processing on the diffusely reflected light, an area array detector receives the light rays in each wave band after the light splitting processing, thus realizing spectral imaging and maintaining the spectral information in each wave band of the object to be scanned.

Description

Hyperspectral scanner

Technical field

The present invention relates to the field of spectral imaging technology, and in particular to a hyperspectral scanner.

Background technique

A scanner is a device that converts graphic or image information into a digital signal by means of optoelectronic technology and digital processing technology. Scanners are commonly used in computer-based instrumentation to capture images and convert them into digital input devices that computers can display, edit, store, and output. Scanners can be used as scanning objects for photos, text pages, drawings, art drawings, photographic film, film film, and even textile, signage panels, printed board samples, etc., to extract and original lines, graphics, text, photos The planar object is converted into a device that can be edited and added to the file. As an optical and mechatronics combined image digital input device, it has been rapidly promoted and widely used since its inception with its excellent performance and low price.

However, the ordinary scanner acquires the information of the three bands, and only the RGB image information is collected, which can meet the daily use requirements in the general application field. However, in some special application fields, such as the use of pigment information for precious samples such as ancient calligraphy and painting, the RGB image information obtained by such a common scanner cannot satisfy other requirements for analyzing, classifying, and identifying the physical and chemical components of the scanned object.

Summary of the invention

In order to reduce the distortion of the scanner, the present invention provides a hyperspectral scanner comprising: a spectral imaging unit, a photoelectric conversion unit, a mechanical transmission unit and a host computer;

The spectral imaging unit is configured to illuminate the object to be scanned with white light, perform spectroscopic processing on the diffuse reflection light of the current scanning line of the object to be scanned, and receive the light of each wavelength band after the spectral processing to generate corresponding light of each wavelength band. Electrical signal

The photoelectric conversion unit is configured to receive the electrical signal, perform analog-to-digital conversion on the electrical signal to obtain a digital signal, send the digital signal to the upper computer, and send a transmission to the mechanical transmission unit signal;

The mechanical transmission unit is configured to, after receiving the transmission signal, drive the spectral imaging unit to move to be opposite to a next scan line of the object to be scanned.

Wherein the spectral imaging unit comprises: a light source, a dispersing component and an area array detector;

The light source is configured to generate white light that is irradiated to the object to be scanned;

The dispersing component is configured to perform spectroscopic processing on the diffuse reflection light of the current scanning line;

The area array detector is configured to receive the light of each wavelength band after the spectroscopic processing to generate an electrical signal corresponding to each band of light.

The spectral imaging unit further includes: a reflective member, an imaging lens, and a slit sequentially disposed between the object to be scanned and the dispersing member;

The reflecting part is configured to reflect the diffuse reflection light of the current scanning line to the imaging lens;

The imaging lens is configured to focus the diffuse reflected light of the current scanning line;

The slit is configured to block light outside the current scanning line.

Wherein the reflecting component comprises: a first mirror, a second mirror and a third mirror, wherein the current scanning line is performed by three reflections of the first mirror, the second mirror and the third mirror Diffuse reflected light is reflected to the imaging lens.

Wherein, the spectral imaging unit further comprises: a focusing lens disposed between the dispersing component and the area array detector.

Wherein, the dispersing component is a prism-grating-prism structure.

The upper computer is configured to process the received digital signal to implement spectral imaging of the object to be scanned.

The hyperspectral scanner further includes: an original table disposed directly above the spectral imaging unit for carrying the object to be scanned.

Wherein, the hyperspectral scanner further comprises: an upper cover disposed above the original table for preventing white light leakage of the spectral imaging unit.

Wherein, the mechanical transmission unit comprises: a motor, a driving belt and a guide rail, and after receiving the transmission signal, the motor drives the spectral imaging unit to slide along the guide rail by driving a belt, so that the spectral imaging unit Moving to the opposite side of the next scan line of the object to be scanned.

After the spectroscope of the present invention performs spectroscopic processing on the diffuse reflection light, the area array detector receives the light of each wavelength band after the spectroscopic processing, realizes spectral imaging, and retains spectral information of each band of the object to be scanned, thereby reducing the scanner. Distortion.

DRAWINGS

1 is a block diagram showing the structure of a hyperspectral scanner according to an embodiment of the present invention;

2 is a schematic diagram showing the specific structure of a spectral imaging unit of a hyperspectral scanner according to an embodiment of the present invention.

detailed description

The specific embodiments of the present invention are further described in detail below with reference to the drawings and embodiments. The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention.

1 is a block diagram of a structure of a hyperspectral scanner according to an embodiment of the present invention; referring to FIG. 1, the hyperspectral scanner includes: a spectral imaging unit 3, a photoelectric conversion unit 4, a mechanical transmission unit 6 and a host computer 5;

The spectral imaging unit 3 is configured to illuminate the object to be scanned with white light, perform spectroscopic processing on the diffuse reflection light of the current scanning line of the object to be scanned, and receive the light of each wavelength band after the spectral processing to generate corresponding wavelength bands. Electrical signal of light;

The photoelectric conversion unit 4 is configured to receive the electrical signal, perform analog-to-digital conversion on the electrical signal, send an analog-to-digital converted electrical signal to the upper computer 5, and send the electrical signal to the mechanical transmission unit 6 Transmission signal

It should be noted that the photoelectric conversion unit 4 is composed of an integrated board, completes the analog-to-digital conversion of the electrical signal and the control of the stepping motor, and is the control part of the entire scanner.

The mechanical transmission unit 6 is configured to drive the spectral imaging unit to move to and after receiving the transmission signal The next scan line of the object to be scanned is opposite.

Since the conventional scanner of the prior art performs the spectral processing on the diffuse reflection light, the information of the three bands of the RGB is collected by three line array detectors, and then the RGB image information is composed according to the information of the three bands of the RGB. However, this ordinary scanner acquires too few RGB image information bands to meet the needs of analyzing the physical and chemical components of the sample.

In the scanner of the embodiment, after the spectroscopic processing is performed on the diffuse reflection light, the image sensor is used to receive the light of each wavelength band after the spectroscopic processing, and the electrical signals generated by the light of each wavelength band are spectrally imaged, and the image is retained. More information on the band and the retained spectral information of hundreds of bands can help people better understand the chemical composition of precious historical materials such as ancient paintings in a non-destructive situation, and provide richer preservation, analysis and post-repair of precious paintings and historical materials. Information.

Referring to FIG. 2, in order to facilitate the generation of electrical signals, the spectral imaging unit 3 optionally includes: a light source 3-1, a dispersing component 3-7, and an area array detector 3-8;

The light source 3-1 is configured to generate white light that is irradiated to the object to be scanned (ie, "A" in the figure);

The dispersing component 3-7 is configured to perform spectroscopic processing on the diffuse reflection light of the current scanning line (the spectroscopic processing is such that light of different wavelengths is at different positions);

The area array detectors 3-8 are configured to receive the light beams of the respective wavelengths after the spectroscopic processing to generate electrical signals corresponding to the light beams of the respective bands (the area array detector detects the spatial dimension information parallel to the direction of the slits, The direction of the vertical slit is used to detect the spectral dimension. The area array detector can be a CCD, sCMOS, flat panel detector or other area array detector with the same function).

Optionally, the spectral imaging unit further includes: a reflective member sequentially disposed between the object to be scanned and the dispersing member, an imaging lens 3-5, and a slit 3-6;

The imaging lens 3-5 is configured to focus the diffuse reflection light of the current scanning line;

The slit 3-6 is used to block light outside the current scanning line.

It should be noted that, by providing the reflecting member, the diffused reflected light can be reflected by the reflecting member and then enter the dispersing member, thereby facilitating the structural layout of the spectral imaging unit; by providing the slit 3-6 and the imaging lens 3-5, The light outside the current scan line can be blocked. Additionally, the slits 3-6, the dispersive device, and the area array detectors 3-8 together determine the final spectral resolution of the scanner.

In addition, the front end of the imaging lens 3-5 adds a filter to the fluorescence spectral imaging mode to achieve the same spectral imaging function.

In order to facilitate the reflection of the diffuse reflection light to the imaging lens, the reflective component optionally includes: a first mirror 3-2, a second mirror 3-3, and a third mirror 3-4, The diffuse reflection light of the current scanning line is reflected by the three reflections of the first mirror 3-2, the second mirror 3-3, and the third mirror 3-4 to the imaging lens 3-5.

In order to facilitate the convergence of the light of each wavelength on the area array detector, the spectral imaging unit further includes: a focusing lens disposed between the dispersing member 3-7 and the area array detector 3-8 ( Not shown in the figure).

The dispersing component can be realized by a liquid crystal tunable filter, an acousto-optic tunable filter, a prism or a grating, etc., but The efficiency and stability of the splitting, optionally, the dispersive component is a prism-grating-prism structure.

In order to facilitate spectral imaging, the upper computer 5 is used to process the received digital signal to achieve spectral imaging of the object to be scanned.

It should be noted that, in addition to processing the received digital signal, the upper computer can also display, process and store the spectral data.

Optionally, the hyperspectral scanner further includes: a document table 2 disposed directly above the spectral imaging unit 3 for carrying the object to be scanned.

It should be noted that the original table 2 is generally a transparent glass with a scale to facilitate the illumination of the white light source and the positioning of the object to be scanned.

Optionally, the hyperspectral scanner further comprises: an upper cover 1 disposed above the original table 2 for preventing white light leakage of the spectral imaging unit.

Optionally, the mechanical transmission unit 6 includes: a motor (the motor may be a transmission device such as a stepping motor or a servo motor), a driving belt and a guide rail, and after receiving the transmission signal, the motor is driven by a driving belt. The spectral imaging unit 3 slides along the guide rail to move the spectral imaging unit to be opposite the next scan line of the object to be scanned.

It should be noted that the overall structure of the mechanical transmission unit is an existing structure, and is not an invention of the present invention. Therefore, specific drawings are not provided herein to specifically describe the same.

The above embodiments are merely illustrative of the present invention and are not intended to be limiting of the invention, and various modifications and changes can be made without departing from the spirit and scope of the invention. Equivalent technical solutions are also within the scope of the invention, and the scope of the invention is defined by the claims.

Industrial applicability

Claims

A hyperspectral scanner, characterized in that the hyperspectral scanner comprises: a spectral imaging unit, a photoelectric conversion unit, a mechanical transmission unit and a host computer;

The spectral imaging unit is configured to illuminate the object to be scanned with white light, perform spectroscopic processing on the diffuse reflection light of the current scanning line of the object to be scanned, and receive the light of each wavelength band after the spectral processing to generate corresponding light of each wavelength band. Electrical signal

The photoelectric conversion unit is configured to receive the electrical signal, perform analog-to-digital conversion on the electrical signal to obtain a digital signal, send the digital signal to the upper computer, and send a transmission to the mechanical transmission unit signal;

The mechanical transmission unit is configured to, after receiving the transmission signal, drive the spectral imaging unit to move to be opposite to a next scan line of the object to be scanned.
The hyperspectral scanner according to claim 1, wherein said spectral imaging unit comprises: a light source, a dispersing member, and an area array detector;

The light source is configured to generate white light that is irradiated to the object to be scanned;

The dispersing component is configured to perform spectroscopic processing on the diffuse reflection light of the current scanning line;

The area array detector is configured to receive the light of each wavelength band after the spectroscopic processing to generate an electrical signal corresponding to each band of light.
The hyperspectral scanner according to claim 2, wherein the spectral imaging unit further comprises: a reflecting member, an imaging lens and a slit which are sequentially disposed between the object to be scanned and the dispersing member;

The reflecting part is configured to reflect the diffuse reflection light of the current scanning line to the imaging lens;

The imaging lens is configured to focus the diffuse reflected light of the current scanning line;

The slit is configured to block light outside the current scanning line.
The hyperspectral scanner according to claim 3, wherein said reflecting member comprises: a first mirror, a second mirror, and a third mirror, said first mirror, said second mirror, and The tertiary reflection of the third mirror reflects the diffusely reflected light of the current scanning line to the imaging lens.
The hyperspectral scanner according to claim 2, wherein said spectral imaging unit further comprises: a focusing lens disposed between said dispersing member and said area array detector.
The hyperspectral scanner of claim 2 wherein said dispersing component is a prism-grating-prism structure.
The hyperspectral scanner according to any one of claims 1 to 6, wherein the upper computer is configured to process the received digital signal to achieve spectral imaging of the object to be scanned.
The hyperspectral scanner according to any one of claims 1 to 6, wherein the hyperspectral scanner further comprises: a document table, the document table being disposed directly above the spectral imaging unit, And carrying the object to be scanned.
A hyperspectral scanner according to claim 8, wherein said hyperspectral scanner further comprises: an upper cover, said upper cover being disposed above said original table for preventing said spectral imaging unit White light leaked.
The hyperspectral scanner according to any one of claims 1 to 6, wherein the mechanical transmission unit comprises: a motor, a driving belt and a guide rail, and the motor passes the driving belt after receiving the transmission signal The spectral imaging unit is caused to slide along the guide rail to move the spectral imaging unit to be opposite to a next scan line of the object to be scanned.