CN212321850U - Single-pixel terahertz detection system - Google Patents
Single-pixel terahertz detection system Download PDFInfo
- Publication number
- CN212321850U CN212321850U CN202021516431.0U CN202021516431U CN212321850U CN 212321850 U CN212321850 U CN 212321850U CN 202021516431 U CN202021516431 U CN 202021516431U CN 212321850 U CN212321850 U CN 212321850U
- Authority
- CN
- China
- Prior art keywords
- terahertz wave
- terahertz
- modulator
- spatial light
- laser
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Abstract
The application discloses single-pixel terahertz detection system, its system modulates the terahertz wave beam reflected by the target object to be detected through the speckle pattern that adopts the single pixel to obtain the light field intensity value of the terahertz wave beam that each single-pixel speckle pattern corresponds, just can acquire imaging data very fast, improve data acquisition efficiency greatly, shorten imaging time, adopt single pixel imaging to all hang down to environment and hardware requirement. Meanwhile, the system imaging resolution and the detection efficiency are greatly improved by combining the strong penetrating power and the detection capability of the terahertz waves, high-quality imaging and detection can be performed on the surfaces or the interiors of various objects, and the practicability is wide.
Description
Technical Field
The application relates to the technical field of terahertz detection, in particular to a single-pixel terahertz detection system.
Background
In the electromagnetic wave spectrum, the frequency of the terahertz wave is in the range of 0.1-10THz, the wavelength is between 3 muj and 1000 muj, and the terahertz wave is an electromagnetic wave between microwave and infrared ray. The harm of terahertz wave radiation to a human body is one thousands of times of that of X rays, and the terahertz wave radiation hardly causes harm to the human body, so that the terahertz wave radiation can be used in the field of security inspection. At present, the security inspection of public places such as high-speed railway stations, airports and the like usually needs two steps: the person to be detected firstly passes through a metal security door (most security doors are based on X-rays at present), and then the whole body of the person is detected by a worker through secondary scanning by using a handheld metal detector. Different from a conventional security check mode, the terahertz wave has strong penetrating power, can detect metal and dangerous articles such as nonmetal, colloid, powder, ceramic, liquid and the like carried by a human body and can be identified simultaneously, and the terahertz security check can complete a security check task only by once detection, so that the security check mode is a very efficient security check mode and has great application value in actual life.
When the terahertz wave technology is used for security inspection, high-quality imaging of the inspected person is a crucial step in the security inspection process. Currently, there are two main types of commonly used terahertz imaging technologies: the method comprises the steps of point-by-point scanning and focal plane array imaging, but the two imaging modes are applied to cause long imaging time due to low image data acquisition efficiency, and meanwhile, the imaging resolution is low and the requirement on hardware is high.
SUMMERY OF THE UTILITY MODEL
The application provides a single-pixel terahertz detection system for solving the technical problems of high image data acquisition efficiency, long imaging time, low imaging resolution and high requirement on hardware in the existing imaging technology.
In view of this, the present application provides a single-pixel terahertz detection system, including: the terahertz wave imaging device comprises a laser source, a spatial light modulator, a projection lens, a terahertz wave source, a terahertz wave imaging lens, a light-controlled terahertz wave modulator, a terahertz wave converging lens and a terahertz wave intensity detector;
the laser source is used for generating a laser beam and then emitting the laser beam to the spatial light modulator;
the spatial light modulator is used for sequentially loading the speckle patterns according to the pre-stored speckle pattern sequence of the single pixel, and meanwhile, the relative position of the spatial light modulator relative to the laser source is limited so that the laser beam emitted into the spatial light modulator completely covers the speckle patterns, and therefore the laser beam is modulated and the modulated laser beam is output;
the projection lens is used for receiving the laser beam output by the spatial light modulator and projecting the laser beam to the light-controlled terahertz wave modulator to form a laser spot;
the terahertz wave source is used for generating a terahertz wave beam and irradiating the object to be detected;
the terahertz wave imaging lens is used for imaging the target object to be detected irradiated by the terahertz wave beam, receiving and projecting the terahertz wave beam reflected by the target object to be detected to the light-controlled terahertz wave modulator, and limiting the relative position of the terahertz wave beam to the light-controlled terahertz wave modulator so that the terahertz wave beam projected to the light-controlled terahertz wave modulator completely covers the laser light spot to realize that the light-controlled terahertz wave modulator modulates the terahertz wave beam;
the light-operated terahertz wave modulator is used for modulating the terahertz wave beam and outputting the modulated terahertz wave beam to the terahertz wave converging lens;
the terahertz wave converging lens is used for converging the terahertz wave beam;
the terahertz wave intensity detector is used for acquiring the light field intensity value of the terahertz wave beam converged by the terahertz wave converging lens.
Preferably, a laser beam expander is arranged between the laser source and the spatial light modulator and used for expanding a laser beam generated by the laser source.
Preferably, a diaphragm with an adjustable aperture size is arranged between the laser beam expander and the spatial light modulator and used for limiting the intensity of the laser beam incident on the spatial light modulator.
Preferably, the terahertz wave intensity detector further comprises a timer, wherein the timer is used for setting the work periods of the spatial light modulator and the terahertz wave intensity detector, so that the terahertz wave intensity detector acquires the light field intensity value of the corresponding terahertz wave beam when the spatial light modulator loads the speckle pattern once.
Preferably, a terahertz wave beam expander is arranged between the terahertz wave source and the target object to be detected and used for expanding terahertz wave beams generated by the terahertz wave source.
According to the technical scheme, the embodiment of the application has the following advantages:
the embodiment of the application provides a single-pixel terahertz detection system, which modulates terahertz wave beams reflected by a target object to be detected by adopting a single-pixel speckle pattern, and obtains the light field intensity value of the terahertz wave beam corresponding to each single-pixel speckle pattern, so that imaging data can be quickly obtained, the data acquisition efficiency is greatly improved, the imaging time is shortened, and the requirements on environment and hardware are low by adopting single-pixel imaging. Meanwhile, the system imaging resolution and the detection efficiency are greatly improved by combining the strong penetrating power and the detection capability of the terahertz waves, high-quality imaging and detection can be performed on the surfaces or the interiors of various objects, and the practicability is wide.
Drawings
Fig. 1 is a schematic structural diagram of a single-pixel terahertz detection system according to an embodiment of the present disclosure;
fig. 2 is a speckle pattern in a single-pixel terahertz detection image acquisition method according to another embodiment of the present application;
fig. 3 is a laser speckle pattern in a single-pixel terahertz detection image acquisition method according to another embodiment of the present application;
fig. 4 is a schematic diagram of a terahertz beam covering a laser spot in a single-pixel terahertz detection image acquisition method according to another embodiment of the present application.
Detailed Description
In order to make the technical solutions of the present application better understood, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.
For easy understanding, please refer to fig. 1, the present application provides a single-pixel terahertz detection system, including: the terahertz wave imaging device comprises a laser source 101, a spatial light modulator 104, a projection lens 105, a terahertz wave source 106, a terahertz wave imaging lens 109, a light-controlled terahertz wave modulator 110, a terahertz wave converging lens 111 and a terahertz wave intensity detector 112;
further, the laser source 101 is used for generating a laser beam and then injecting the laser beam into the spatial light modulator 104;
further, the spatial light modulator 104 is configured to sequentially load the speckle patterns therein according to a pre-stored speckle pattern sequence of a single pixel, and at the same time, by limiting a relative position between the spatial light modulator 104 and the laser source 101, the laser beam incident into the spatial light modulator 104 completely covers the speckle patterns, so as to modulate the laser beam and output the modulated laser beam;
it should be noted that, as shown in fig. 2, the speckle pattern loaded by the spatial light modulator 104 in sequence is a single sheet, while the pre-stored speckle pattern sequence may be several sheets, and the pre-stored speckle pattern is generated by the computer 113 and loaded into the spatial light modulator 104. Meanwhile, the relative position of the laser beam with respect to the laser source 101 is not limited, as long as the laser beam entering the spatial light modulator 104 can completely cover the speckle pattern, and when the laser beam entering the spatial light modulator 104 completely covers the speckle pattern, the amplitude of the laser beam is changed, so that modulation is realized.
Further, the projection lens 105 is configured to receive the laser beam output by the spatial light modulator 104, and project the laser beam into the light-controlled terahertz modulator 110 to form a laser spot;
it will be appreciated that interference of the laser beam by the speckle pattern will naturally result in a laser spot in the output projection, as shown in figure 3.
Further, the terahertz wave source 106 is used for generating a terahertz wave beam and irradiating the object to be detected 108;
further, the terahertz wave imaging lens 109 is configured to image the target object 108 to be detected irradiated by the terahertz wave beam, and at the same time, receive and project the terahertz wave beam reflected by the target object 108 to the light-controlled terahertz wave modulator 110, and by limiting a relative position of the terahertz wave beam with respect to the light-controlled terahertz wave modulator 110, the terahertz wave beam projected to the light-controlled terahertz wave modulator 110 completely covers the laser spot, as shown in fig. 4, so as to realize that the terahertz wave beam is modulated by the light-controlled terahertz wave modulator 110;
it can be understood that after the terahertz wave beam projected to the light-controlled terahertz wave modulator 110 completely covers the laser spot, the transmittance of the light-controlled terahertz wave modulator 110 can be changed, so that the amplitude of the incident terahertz wave beam is modulated, and the amplitude of the terahertz wave beam is changed.
Further, the optically-controlled terahertz wave modulator 110 is configured to modulate a terahertz wave beam and output the modulated terahertz wave beam to the terahertz wave converging lens 111;
further, the terahertz wave converging lens 111 is used for converging the terahertz wave beam;
the terahertz wave intensity detector 112 is used for acquiring the light field intensity value of the terahertz wave beam converged by the terahertz wave converging lens 111.
After the terahertz wave converging lens 111 converges the terahertz wave beam, the terahertz wave beam is incident on the terahertz wave intensity detector 112.
Further, a laser beam expander 102 is disposed between the laser source 101 and the spatial light modulator 104, and is used for expanding a laser beam generated by the laser source 101.
It should be noted that, according to actual situations, the relative positions between the laser beam expander 102 and the laser source 101 and the spatial light modulator 104 need to be adjusted so that the laser beam can completely cover the speckle pattern.
Further, an aperture 103 with an adjustable aperture size is disposed between the laser beam expander and the spatial light modulator 104, and is used for limiting the intensity of the laser beam incident on the spatial light modulator 104.
It should be noted that, according to actual situations, the relative positions between the diaphragm 103, the laser beam expander 102, and the laser source 101 and the spatial light modulator 104 need to be adjusted so that the laser beam can completely cover the speckle pattern.
Further, a timer is further included, and the timer is used for setting the duty cycles of the spatial light modulator 104 and the terahertz wave intensity detector 112, so that the terahertz wave intensity detector 112 acquires the optical field intensity value of the corresponding terahertz wave beam when the spatial light modulator 104 loads the speckle pattern once.
Further, a terahertz wave beam expander is arranged between the terahertz wave source 106 and the target object 108 to be measured and used for expanding terahertz wave beams generated by the terahertz wave source 106.
It should be noted that, the working process of this embodiment is that, (1) the speckle patterns in the speckle patterns are sequentially loaded by the spatial light modulator according to the pre-stored speckle pattern sequence; (2) the laser beam is emitted to the spatial light modulator through the laser source and completely covers the speckle pattern loaded in advance by the spatial light modulator, so that the laser beam is modulated; (3) after the laser beam is modulated by the spatial light modulator, the laser beam is output to the projection lens, the laser beam is projected to the light-controlled terahertz wave modulator through the projection lens, and a laser spot is formed in the light-controlled terahertz wave modulator; (4) a terahertz wave source emits a terahertz wave beam, and the terahertz wave beam is expanded by a terahertz wave beam expander and then is irradiated to a target object to be detected; (5) imaging a target object to be detected irradiated by a terahertz wave beam through a terahertz wave imaging lens, receiving and projecting the terahertz wave beam reflected by the target object to be detected to a light-controlled terahertz wave modulator, and enabling the terahertz wave beam projected to the light-controlled terahertz wave modulator to completely cover a laser spot so as to realize modulation of the terahertz wave beam by the light-controlled terahertz wave modulator; (6) outputting the modulated terahertz wave beams to a terahertz wave converging lens through a light-controlled terahertz wave modulator; (7) after the terahertz wave beams are converged by the terahertz wave converging lens, the terahertz wave intensity detector is used for acquiring the light field intensity value of the terahertz wave beams converged by the terahertz wave converging lens, which corresponds to each speckle pattern. And the image reconstruction can be carried out on the target object to be detected through the obtained light field intensity value of the terahertz wave beam corresponding to each speckle pattern of the speckle pattern sequence, so that the image of the target object to be detected is obtained.
The above embodiments are only used for illustrating the technical solutions of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions in the embodiments of the present application.
Claims (5)
1. A single-pixel terahertz detection system, comprising: the terahertz wave imaging device comprises a laser source, a spatial light modulator, a projection lens, a terahertz wave source, a terahertz wave imaging lens, a light-controlled terahertz wave modulator, a terahertz wave converging lens and a terahertz wave intensity detector;
the laser source is used for generating a laser beam and then emitting the laser beam to the spatial light modulator;
the spatial light modulator is used for sequentially loading the speckle patterns according to the pre-stored speckle pattern sequence of the single pixel, and meanwhile, the relative position of the spatial light modulator relative to the laser source is limited so that the laser beam emitted into the spatial light modulator completely covers the speckle patterns, and therefore the laser beam is modulated and the modulated laser beam is output;
the projection lens is used for receiving the laser beam output by the spatial light modulator and projecting the laser beam to the light-controlled terahertz wave modulator to form a laser spot;
the terahertz wave source is used for generating a terahertz wave beam and irradiating the object to be detected;
the terahertz wave imaging lens is used for imaging the target object to be detected irradiated by the terahertz wave beam, receiving and projecting the terahertz wave beam reflected by the target object to be detected to the light-controlled terahertz wave modulator, and limiting the relative position of the terahertz wave beam to the light-controlled terahertz wave modulator so that the terahertz wave beam projected to the light-controlled terahertz wave modulator completely covers the laser light spot to realize that the light-controlled terahertz wave modulator modulates the terahertz wave beam;
the light-operated terahertz wave modulator is used for modulating the terahertz wave beam and outputting the modulated terahertz wave beam to the terahertz wave converging lens;
the terahertz wave converging lens is used for converging the terahertz wave beam;
the terahertz wave intensity detector is used for acquiring the light field intensity value of the terahertz wave beam converged by the terahertz wave converging lens.
2. The single-pixel terahertz detection system according to claim 1, wherein a laser beam expander is arranged between the laser source and the spatial light modulator, and is used for expanding a laser beam generated by the laser source.
3. The single-pixel terahertz detection system according to claim 2, wherein a diaphragm with an adjustable aperture size is arranged between the laser beam expander and the spatial light modulator, and is used for limiting the intensity of a laser beam incident on the spatial light modulator.
4. The single-pixel terahertz detection system of claim 1, further comprising a timer for setting a duty cycle of the spatial light modulator and the terahertz wave intensity detector such that the terahertz wave intensity detector acquires a light field intensity value of a corresponding terahertz beam every time the spatial light modulator is loaded with the speckle pattern.
5. The single-pixel terahertz detection system according to claim 1, wherein a terahertz wave beam expander is arranged between the terahertz wave source and the target object to be detected, and is used for expanding a terahertz wave beam generated by the terahertz wave source.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202021516431.0U CN212321850U (en) | 2020-07-28 | 2020-07-28 | Single-pixel terahertz detection system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202021516431.0U CN212321850U (en) | 2020-07-28 | 2020-07-28 | Single-pixel terahertz detection system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN212321850U true CN212321850U (en) | 2021-01-08 |
Family
ID=74036130
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202021516431.0U Active CN212321850U (en) | 2020-07-28 | 2020-07-28 | Single-pixel terahertz detection system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN212321850U (en) |
-
2020
- 2020-07-28 CN CN202021516431.0U patent/CN212321850U/en active Active
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111736171A (en) | Single-pixel terahertz detection system and image acquisition method | |
| CN103575654B (en) | A kind of method and system improving Terahertz scanning imagery speed | |
| JP6937735B2 (en) | Laser ranging and lighting | |
| WO2018045779A1 (en) | Terahertz imaging system and terahertz security check device | |
| US20070024842A1 (en) | Distance measurement device and distance measurement method | |
| US8605147B2 (en) | Device for recording images of an object scene | |
| CA2383834A1 (en) | Method and apparatus for spectrometric analysis of turbid, pharmaceutical samples | |
| CN107024850B (en) | High-speed structures light 3-D imaging system | |
| CN108363069A (en) | Relevance imaging device and method based on distributed semiconductor laser array | |
| CN109142267B (en) | Real-time terahertz imaging device and method | |
| CN111141701A (en) | Rapid super-resolution imaging method and system based on terahertz single pulse | |
| CN107942338A (en) | A kind of multi-wavelength relevance imaging system based on Digital Micromirror Device | |
| US20050253071A1 (en) | Diffraction mode terahertz tomography | |
| CN106996918A (en) | A kind of terahertz imaging system based on Photonics Technology | |
| JP2014219404A (en) | Device and method for three-dimensionally measuring surface simultaneously in several wavelengths | |
| CN212321850U (en) | Single-pixel terahertz detection system | |
| Alkus et al. | Stand-off through-the-wall W-band millimeter-wave imaging using compressive sensing | |
| Augustin et al. | Terahertz dynamic aperture imaging at standoff distances using a compressed sensing protocol | |
| TW201713933A (en) | Mail detection device and method | |
| CN209911223U (en) | Terahertz high-resolution rapid imaging device based on block compressed sensing | |
| JP2013217649A (en) | Terahertz imaging device, method for eliminating interference patterns from terahertz image, and program | |
| EP3827287B1 (en) | Scintillating detectors for quality assurance of a therapy photon beam | |
| CN107978209B (en) | Remote Fourier telescope imaging demonstration system | |
| CN110297255A (en) | 3D imaging system and 3D imaging method | |
| CN106596062A (en) | Laser synchronous infrared video acquisition device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |