CN204989511U - Multifrequency terahertz is imaging system now - Google Patents

Abstract

The utility model discloses a multifrequency terahertz is imaging system now, it includes terahertz detector, image device and the display device of optical system, a plurality of different frequencies now, wherein, terahertz optical system now acquires by the human terahertz wave who sends of detection to assemble it, the detector of a plurality of different frequencies is received respectively the terahertz terahertz wave that optical system assembled now converts it to the signal of telecommunication, the image device basis the signal of telecommunication and the imaging position of detector transmission form images to the human body, and the transmission is given image device, display device will the picture that image device became shows on the display screen. Utilize the utility model discloses a multifrequency terahertz is imaging system now can detect human dangerous goods of carrying to can classify to it.

Description

Multifrequency terahertz imaging system

Technical field

The utility model relates to the technical field of terahertz imaging, particularly relates to the multifrequency terahertz imaging system for objects such as human body and the article carried thereof and the luggage that runs on a moving belt.

Background technology

Terahertz (THz) ripple refers to frequency range electromagnetic wave (1THz=1012Hz) of (namely wavelength is 3000-30) between 0.1-10THz.The long-wave band of THz wave and millimeter wave (submillimeter wave) coincide, and short-wave band and infrared ray (far infrared) coincide, and belong to forefathers and study less wave band.Terahertz has a lot of unique advantages, and the photon energy of such as THz wave, far below visible ray and X ray, is only the per mille of visible ray, X ray 1,000,000/, minimum to harm, harmful ionizing event can not be produced to biological tissue.THz wave wavelength is longer, and the electromagnetic wavelength of 1THz is 300, is used for carrying out being subject to material diffuse transmission influence little when measurement detects; In addition, THz wave has good penetration capacity, such as terahertz emission can penetrate as fat, carbon plate, cloth, plastics, pottery, leather and fur, even most of nonmetallic materials and apolar substance with very little decay, absorbed in a large number or reflection by metal, colloid, explosive, drugs, currency and liquid etc. simultaneously.Therefore Terahertz Technology is as public security protection detection technique, and on airport, the crowded applications demand in subway, railway station etc. is very large.

Current, what be applied to terahertz imaging system is mainly imaging and passive imaging technology, by to human body or object fast scan imaging, reach the target of the dangerous goods of placing in things concealed entrained by human body or object (such as luggage etc.) etc., but can not classify to detected article, and image taking speed and image quality need to be improved further.

Utility model content

In view of the above problems, the utility model is proposed to provide a kind of multifrequency terahertz imaging system overcoming the problems referred to above or solve the problem at least in part.

According to the utility model, provide a kind of multifrequency terahertz imaging system, it comprises terahertz optics system, the detector of multiple different frequency, imaging device and display device.Wherein, described terahertz optics system obtains the THz wave that detected human body sends and the background THz wave reflected through the article scattering entrained by detected human body, transmission and/or the THz wave after absorbing or object to be detected, and assembles it; The detector of described multiple different frequency receives the THz wave of the different frequency that described terahertz optics system is assembled respectively, and converts the THz wave of respective frequencies to electric signal respectively; The electric signal that described imaging device transmits according to described detector carries out imaging to detected human body or object to be detected; Described display device by described imaging device imaging display on a display screen.

Alternatively, described terahertz optics system can comprise scanister and condenser lens, wherein, described scanister is suitable for treating human body and entrained article or object to be detected thereof and scans, the THz wave obtaining detected human body radiation and the background THz wave reflected through the article scattering entrained by detected human body, transmission and/or the THz wave after absorbing or object to be detected; The THz wave that described condenser lens is suitable for described scanister obtains is assembled.

Alternatively, described scanister adopts the regular polygon prism that can rotate to realize, and the side of this regular polygon prism is plane reflection face, the received THz wave from detected human body can be reflexed on focalizer.Described focalizer is convex lens.

Alternatively, described scanister and described focalizer are realized by the ellipsoidal mirror that can rotate, and scanning and focusing function unite two into one by this ellipsoidal mirror.

Alternatively, the detector of described multiple different frequency is multiple detectors of two kinds or two or more frequency.Alternatively, described multiple detector array is orthogonal.Such as when 12 detectors of use 3 kinds of frequencies, the detector of often kind of frequency are 4, described 12 detector array become 3 × 4 matrixes or 4 × 3 matrixes.Alternatively, described multiple detector array is in line type.Alternatively, described multiple detector lines up multirow stragglyly.Such as when 12 detectors of use three kinds of frequencies, the detector of often kind of frequency are 4, described 12 detector array become three row, and middle row differs the distance of the width of half detector with upper and lower two row.

Utilize multifrequency terahertz imaging system of the present utility model, the dangerous goods filled in the object such as dangerous goods or luggage entrained by human body can be detected more comprehensively, exactly, and can classify to it.

Above-mentioned explanation is only the general introduction of technical solutions of the utility model, in order to technological means of the present utility model can be better understood, and can be implemented according to the content of instructions, and can become apparent, below especially exemplified by embodiment of the present utility model to allow above-mentioned and other objects, features and advantages of the present utility model.

Accompanying drawing explanation

By reading hereafter detailed description of the preferred embodiment, various other advantage and benefit will become cheer and bright for those of ordinary skill in the art.Accompanying drawing only for illustrating the object of preferred implementation, and is not thought restriction of the present utility model.And in whole accompanying drawing, represent identical parts by identical reference symbol.In the accompanying drawings:

Fig. 1 shows the schematic diagram of the multifrequency terahertz imaging system according to an embodiment of the present utility model;

Fig. 2 A and Fig. 2 B shows and is undertaken detecting by multifrequency terahertz imaging system of the present utility model and the image of the detected human body obtained;

Fig. 3 shows the schematic diagram of a kind of embodiment of the disposing way according to multiple detector of the present utility model;

Fig. 4 shows the schematic diagram of the another kind of embodiment of the disposing way according to multiple detector of the present utility model; And

Fig. 5 shows the schematic diagram of another embodiment of the disposing way according to multiple detector of the present utility model.

Embodiment

Below with reference to accompanying drawings exemplary embodiment of the present disclosure is described in more detail.Although show exemplary embodiment of the present disclosure in accompanying drawing, however should be appreciated that can realize the disclosure in a variety of manners and not should limit by the embodiment set forth here.On the contrary, provide these embodiments to be in order to more thoroughly the disclosure can be understood, and complete for the scope of the present disclosure can be conveyed to those skilled in the art.

Fig. 1 shows signal Figure 100 of the multifrequency terahertz imaging system according to a kind of embodiment of the present utility model.As shown in Figure 1, this multifrequency terahertz imaging system 100 comprises: the detector 140 of terahertz optics system 110, multiple different frequency, imaging device 150 and display device 160.Wherein, described terahertz optics system 110 obtains the background THz wave that the THz wave of detected human body 170 radiation and the THz wave after the article scattering entrained by detected human body, transmission and/or absorption or object to be detected 170 reflect.The dangerous material such as the article entrained by described detected human body such as explosive, gun, cutter.Described object to be detected comprises the luggage etc. that the dangerous material such as explosive, gun, cutter are housed.Usual people knows from experience the THz wave of radiation multi-frequency.Around object to be detected, also have the object of the THz wave of radiation different frequency, detected material cognition reflects the THz wave of other object institute radiation around it.After described terahertz optics system 110 obtains the background THz wave that the THz wave of detected human body radiation and the THz wave after the article scattering entrained by detected human body, transmission and/or absorption or object to be detected reflect, transmit it to the detector 140 of multiple different frequency, the detector 140 of different frequency converts the THz wave of respective frequencies to electric signal, exports to imaging device 150.The described electric signal that imaging device 150 transmits according to different detector carries out imaging to detected human body 170 and entrained article thereof or object to be detected 170, then imaging is presented in display device 160.

Wherein, described terahertz optics system 110 can comprise scanister 120 and focalizer 130.Described scanister 120 is suitable for treating human body or object 170 scans, and it can adopt rotary two circular flat catoptrons that are relative, off-axis to realize two-dimentional point by point scanning; Also can adopt tilting mirror to realize.Described tilting mirror can adopt rotating regular polygon prism, that is, polyhedral prism xsect is regular polygon.The side of described regular polygon prism is plane reflection face, when described tilting mirror rotates, the background THz wave that the THz wave from detected human body received by it and the THz wave after the article scattering entrained by detected human body, transmission and/or absorption or object to be detected reflect constantly can be reflexed on focalizer 130.Such as can adopt the regular five-hedron prism that can rotate, its THz wave that human body can be sent projects on focalizer 130 by the reflection in the plane reflection face on tilting mirror, can be enclosed the land to human body one by the rotation of tilting mirror and scan, thus the THz wave that constantly can obtain the radiation of detected human body institute and the background THz wave reflected through the article scattering entrained by detected human body, transmission and/or the THz wave after absorbing or object to be detected.Namely scanister 120 starts working after terahertz imaging system 100 of the present utility model is energized.The Terahertz light obtained when focalizer 130 is suitable for scanister 120 being scanned detected human body or object to be detected is assembled, then the detector 140 of different frequency is sent to, thus facilitate detector 140 to detect, because the probe of detector 140 is smaller, if investigative range is too large, the Effect on Detecting of detector 140 can be affected.Focalizer 130 such as can adopt convex lens to realize.

In addition, described scanister 120 and focalizer 130 also can adopt ellipsoidal mirror to realize, and scanning and focusing function unite two into one by this ellipsoidal mirror.

Described detector 140 comprises multiple detectors with different frequency, also can be the detector with multiple probe, and the look-in frequency of different probes can be different.The probe of the detector 140 of different frequency or the different frequency of detector 140 detects to the THz wave of the different frequency of detected human body 170 radiation and through the background THz wave that the article scattering entrained by detected human body, transmission and/or the THz wave after absorbing or object to be detected 170 reflect with different frequencies respectively.Alternatively, on the detector 140 of the described multiple different frequency focal plane that is positioned over focalizer 130 in terahertz optics system 110 or position near it.Described detector can be such as the pyroelectric detector of detection microbolometric.

How main detailed description in detail for human body and entrained article thereof uses multiple detector to detect it below.Applicable equally to the detection of the luggage on other object such as travelling belt, just at this moment detected THz wave comes from the reflection of the objects such as described luggage to the Terahertz of its surrounding objects radiation.

Because detected human body can the THz wave of radiation different frequency, when detected human body carries different article, the different article transmissions of THz wave entrained by human body of these different frequencies, scattering and/or after absorbing, the change of its intensity is also different, after the detector of different frequency detects the different THz wave of these Strength Changes, can produce different electric signal, this can reflect that different article are to the transmission of THz wave, scattering and/or absorption characteristic.Imaging device 150 carries out imaging based on different electric signal, and the detected human body background image carried around the image in the region of these different objects and these objects is formed and contrasts, and thus can identify pattern and the kind of these article.

Such as, the detector of three different look-in frequencies can be adopted to detect, the look-in frequency that these three detectors adopt such as is respectively 360GHz, 220GHz and 94GHz, when detected human body 170 carries explosive, cutter, during the article such as pistol, due to explosive, cutter, the article such as pistol are to the transmission of the THz wave of human body institute radiation, scattering, and/or absorption characteristic is different, so explosive, cutter, the article such as pistol are different to the transmitance of the THz wave of the different frequency of the human body institute radiation of its position, thus the Terahertz wave intensity making these human bodies give off changes.The detector of different look-in frequency detects the THz wave of different frequency and converts thereof into electric signal, such as voltage signal, and the power of the THz wave of the different parts institute radiation of described electric signal and detected human body linearly changes.Such as, carry the THz wave of the human body parts radiation of explosive, because different explosives is to the difference of the transmission of the THz wave of different frequency, scattering and/or absorption characteristic, make described THz wave through 360GHz, after the detector detection of 220GHz and 94GHz, obtain voltage A, B, C respectively, and the signal of A ≠ B ≠ C.And carry the THz wave of the human body radiation of the article such as metal knife, pistol, after the detector detection of 360GHz, 220GHz and 94GHz, obtain the signal of voltage D, D, D respectively.Voltage A, B, C, D are less than detection to the THz wave of the human body institute radiation of not placing the article such as explosive, cutter, pistol and the voltage obtained.Therefore, when the electric signal that imaging device 150 produces based on the detector 140 of same frequency and image space thereof (based on the detected human body corresponding to the THz wave that terahertz optics system 110 is assembled or object position and determine) carry out imaging time, will be formed deep mixed at the different parts of human body, there is the image of different contrast, and then the image of the different colours to be formed by the detector based on different frequency is (when such as using the detector of three kinds of frequencies to detect, then can form the image of 3 kinds of different colours) merge, image recognition effect can be improved further like this.Fig. 2 A shows image formed before detected human body, and as shown in Figure 2 A, there is black image everywhere on its chest, belly and the right side across side, and this illustrates that these four positions of detected human body are all placed with article.Fig. 2 B shows image formed by the detected human body back side, and as shown in Figure 2 B, its RG illustrates that a shape resembles the black image of pistol.In reality, the different images that imaging device 150 presents for different positions, article place, shape etc. according to presenting when the difference on institute's formation voltage signal under the detector of different look-in frequency and imaging thereof can mark different colors on image, thus testing staff can be identified soon what article be.

Utilize multifrequency terahertz imaging system of the present utility model, can detect that the different article entrained to detected human body can detect more delicately with it, as long as because carry different article, will to the THz wave generation transmission in various degree of human body institute radiation, scattering and/or absorption, namely THz wave generation decay is in various degree made, thus final formed image will produce deep mixed, difform shadow or be labeled out different colours at different positions, thus testing staff is reminded to note.

In addition, some article are very high to the transmitance of the THz wave of a certain frequency, when this article be hidden in detected human body with it time, if use the detector of this frequency to detect, then almost detect less than this article.But this article then may be not too high to the transmitance of the THz wave of other frequency, namely this article to the absorption of other frequency described and/or scattering ratio larger, so, when using the detector of other frequency described to detect, the THz wave that just can detect this frequency is attenuated, thus can detect detected human body and carry this article with it.Such as, if first object absorbs comparatively strong to the THz wave of 220GHz, but weak to the absorption of 360GHz.Second object absorbs more weak to the THz wave of 220GHz frequency, but absorbs strong to the THz wave of 360GHz.Like this, can be detected the existence of first object by the detector of 220GHz, be ambiguous to the detection of second object; Then can be detected the existence of second object by the detector of 360GHz, be ambiguous to the detection of first object.Therefore, by using multifrequency terahertz imaging system of the present utility model just can improve recall rate to the suspicious object entrained by detected personnel, prevent undetected.And use the devices such as X ray to detect human body, injury effect is had on the one hand to human body, on the other hand, some article does not have barrier effect to X ray or barrier effect is very weak, such as some polymkeric substance and foamed material, can't image be formed after X ray detects, therefore there will be undetected problem.But utilize multifrequency terahertz imaging system of the present utility model, then can avoid this problem.

The quantity of the detector of the different frequency adopted is determined as required, and the quantity of the detector of usual different frequency is identical, and image procossing follow-up like this can be easier.In addition, the detector of two kinds of different look-in frequencies can be adopted to detect, the detector of more than three kinds different look-in frequencies also can be adopted to detect, can determine the response of different frequency according to the kind of detected article and they.Equally, multiple detector with the probe of different look-in frequency can also be adopted.

When adopting the detector 140 of multiple different frequency, wherein the disposing way of detector 140 can affect scanning imagery speed and also can have an impact to the follow-up image procossing that carries out of imaging device 150.When the detected human body of multifrequency terahertz imaging system of the present utility model distance or object nearer, then detector is also the closer to detected human body or object, thus the signal of detected THz wave is stronger, thus the electric signal of correspondence that detector is formed also can be stronger, and then the resolution of imaging device imaging also can be higher.In addition, when the detector used is more than 140, the area of space area that when each terahertz optics system 110 scans, these detectors detect just becomes large, for the imaging area scope determined, time needed for scanning imagery will reduce, and the speed of imaging will be faster.

Fig. 3 shows the schematic diagram of a kind of embodiment of the disposing way of multiple detector.As shown in Figure 3, when employing 12 detectors, the first row linearly puts the detector of 4 94GHz, and the second row linearly puts the detector of 4 220GHz, and the third line puts the detector of 4 360GHz, forms 3X4 array.This disposing way is simple, easy processing and fabricating and the system integration.As previously mentioned, the detector adopted due to the mode shown in Fig. 3 is many, so image taking speed can be accelerated.

In addition, above-mentioned 12 detectors are also not limited to above-mentioned a kind of disposing way, such as, all at least put the detector of a different frequency in each row.Further, above-mentioned 12 detectors also can put into 4X3 array etc.In a word, the good disposing way of a kind of effect can according to circumstances be selected.

When multiple detector adopts the disposing way shown in Fig. 3, foregoing tilting mirror can be adopted as scanister 120, when tilting mirror is rotated at every turn, described 12 detectors can receive corresponding THz wave simultaneously.

Fig. 4 shows the schematic diagram of the another kind of embodiment of the disposing way of multiple detector.As shown in Figure 4, three detectors are arranged in a line shape from top to bottom, and the frequency of three detectors is respectively 94GHz from top to bottom, 220GHz, 360GHz.This disposing way only have employed three detectors, and quantity is few, and cost is low, but image taking speed is compared, the mode of Fig. 4 more slowly.

In addition, three detectors in Fig. 4 also can put into straight line shape from left to right, and the position of the detector of different frequency is also not limited to from left to right be respectively 94GHz, the detector of 220GHz, 360GHz.The utility model is not particularly limited to this.

When multiple detector adopts the disposing way shown in Fig. 4, foregoing two of can rotate circular flat catoptron that is relative, off-axis can be adopted to realize two-dimentional point by point scanning as scanister 120, by the High Rotation Speed of circular flat catoptron, make described 3 detectors can receive corresponding THz wave simultaneously.

Fig. 5 shows the schematic diagram of another embodiment comprising the disposing way of popping one's head in the detector of multiple probe.As shown in Figure 5,12 detectors 140 line up three row by the mode shown in Fig. 5, and often row comprises 4 detectors.Wherein the detector of the first row differs the width of half detector (when adopting single pixel detector with the detector of the second row, half-pixel is differed between the detector of adjacent rows), the detector of the second row differs the width of half detector with the detector of the third line.The detector that mode shown in Fig. 5 uses is many, and image taking speed is fast.Due to the width of half detector that mutually staggers between adjacent rows, the actual electric signal produced also can stagger in the distribution of the corresponding pixel points of imaging, like this, imaging device 150 when carrying out image procossing can on the basis of these actual pixels interpolation and then generate more pixel, thus can imaging resolution be improved, the disposing way shown in Fig. 5 makes the imaging resolution of imaging device 150 can improve compared with the disposing way shown in Fig. 3 a lot.Fig. 5 illustrate only a kind of disposing way that detector adjacent rows offsets one from another, also other similar disposing way can be taked, such as, in Fig. 5, the width of the third line and the second row wrong half detector to the right makes the third line and the first row to stagger the width of a detector.The utility model is to this and be not specifically limited.In addition, the distance staggered also can adjust as required.

Above description just provides the embodiment of the disposing way of several multiple detector, the utility model is not limited to several disposing way recited above, also the detector of more or less different frequency can be adopted as required, corresponding scanister and focalizer also can correspondingly adjust, to obtain better effect, here, the utility model does not also limit the scanister of corresponding use when adopting multiple detector of different disposing way and focalizer.

Described imaging device 150 can be the equipment such as computing machine, single-chip microcomputer or microprocessor, for the electric signal that produces according to detector and image space thereof, carries out imaging to detected human body and entrained article thereof or object to be detected.

Described display device 160, it is connected with imaging device 150, can be computer display or other for show imaging device 150 become the device of image.

Utilize multifrequency terahertz imaging system of the present utility model, can be detected the prohibited items filled in detected human body and the object such as the hidden prohibited items carried and luggage thereof by the detector of multiple frequency, thus make testing staff be easy to whether comprise prohibited items in the particular location of the suspicious object got entrained by detected human body and object to be detected, and can according to different article to the article filled in the objects such as the difference of the transmitance of the THz wave of the different frequency of human body institute radiation and luggage to the reflection in various degree of the THz wave of ambient radiation, detect with the detector of different frequencies, obtain different electric signal, by carrying out imaging based on described electric signal and image space thereof and process, if indicate different colors again, different article can be identified very soon based on different colors and the shape of the image formed, thus reach especially to the hidden dangerous goods entrained by human body or object, as explosive, cutter, pistols etc. carry out the object identified fast.In addition, utilize multifrequency terahertz imaging system of the present utility model, image taking speed is fast, and recognition capability is strong, and image quality is high.

In instructions provided herein, describe a large amount of detail.But can understand, embodiment of the present utility model can be put into practice when not having these details.In some instances, be not shown specifically known method, structure and technology, so that not fuzzy understanding of this description.

Similarly, be to be understood that, in order to simplify the disclosure and to help to understand in each inventive aspect one or more, in the description above to exemplary embodiment of the present utility model, each feature of the present utility model is grouped together in single embodiment, figure or the description to it sometimes.But, the method for the disclosure should be construed to the following intention of reflection: namely the utility model required for protection requires feature more more than the feature clearly recorded in each claim.Or rather, as claims below reflect, all features of disclosed single embodiment before inventive aspect is to be less than.Therefore, the claims following embodiment are incorporated to this embodiment thus clearly, and wherein each claim itself is as independent embodiment of the present utility model.

Those skilled in the art are appreciated that and adaptively can change the module in the equipment in embodiment and they are arranged in one or more equipment different from this embodiment.Module in embodiment or unit or assembly can be combined into a module or unit or assembly, and multiple submodule or subelement or sub-component can be put them in addition.Except at least some in such feature and/or process or unit be mutually repel except, any combination can be adopted to combine all processes of all features disclosed in this instructions (comprising adjoint claim, summary and accompanying drawing) and so disclosed any method or equipment or unit.Unless expressly stated otherwise, each feature disclosed in this instructions (comprising adjoint claim, summary and accompanying drawing) can by providing identical, alternative features that is equivalent or similar object replaces.

In addition, those skilled in the art can understand, although embodiments more described herein to comprise in other embodiment some included feature instead of further feature, the combination of the feature of different embodiment means and to be within scope of the present utility model and to form different embodiments.Such as, in the following claims, the one of any of embodiment required for protection can use with arbitrary array mode.

All parts embodiment of the present utility model with hardware implementing, or can realize with the software module run on one or more processor, or realizes with their combination.It will be understood by those of skill in the art that the some or all functions that microprocessor or digital signal processor (DSP) can be used in practice to realize according to the some or all parts in the browser client of the utility model embodiment.The utility model can also be embodied as part or all equipment for performing method as described herein or device program (such as, computer program and computer program).Realizing program of the present utility model and can store on a computer-readable medium like this, or the form of one or more signal can be had.Such signal can be downloaded from internet website and obtain, or provides on carrier signal, or provides with any other form.

It should be noted that above-described embodiment is described the utility model instead of limits the utility model, and those skilled in the art can design alternative embodiment when not departing from the scope of claims.In the claims, any reference symbol between bracket should be configured to limitations on claims.Word " comprises " not to be got rid of existence and does not arrange element in the claims or step.Word "a" or "an" before being positioned at element is not got rid of and be there is multiple such element.The utility model can by means of including the hardware of some different elements and realizing by means of the computing machine of suitably programming.In the unit claim listing some devices, several in these devices can be carry out imbody by same hardware branch.Word first, second and third-class use do not represent any order.Can be title by these word explanations.

Claims (10)

1. multifrequency terahertz imaging system, is characterized in that, described system comprises: the detector of terahertz optics system, multiple different frequency, imaging device and display device, wherein,

Described terahertz optics system obtains the THz wave that detected human body sends and the background THz wave reflected through the article scattering entrained by detected human body, transmission and/or the THz wave after absorbing or object to be detected, and assembles it; The detector of described multiple different frequency receives the THz wave of the different frequency that described terahertz optics system is assembled respectively, and converts the THz wave of respective frequencies to electric signal respectively, is then transferred to described imaging device; Described imaging device receives the electric signal of described detector transmission, and carries out imaging according to described electric signal and image space thereof to detected human body; Described display device by described imaging device imaging display on a display screen.

2. multifrequency terahertz imaging system according to claim 1, is characterized in that,

Described terahertz optics system comprises scanister and focalizer, wherein,

Described scanister is suitable for scanning detected human body and entrained article thereof or object to be detected, obtains the background THz wave that the THz wave of detected human body radiation and the THz wave after the article scattering entrained by detected human body, transmission and/or absorption or object to be detected reflect; The THz wave that described focalizer is suitable for described scanister obtains is assembled.

3. multifrequency terahertz imaging system according to claim 2, is characterized in that,

Described scanister and described focalizer are realized by the ellipsoidal mirror that can rotate.

4. multifrequency terahertz imaging system according to claim 2, is characterized in that,

Described scanister is the regular polygon prism that can rotate, and its side is plane reflection face, the received THz wave from detected human body can be reflexed on focalizer;

Described focalizer is convex lens.

5. the multifrequency terahertz imaging system according to any one of claim 1-4, is characterized in that,

The detector of described multiple different frequency is multiple detectors of two kinds or two or more frequency.

6. multifrequency terahertz imaging system according to claim 5, is characterized in that,

Described multiple detector array is orthogonal.

7. multifrequency terahertz imaging system according to claim 6, is characterized in that,

When 12 detectors of use 3 kinds of frequencies, the detector of often kind of frequency are 4, described 12 detector array become 3 × 4 matrixes or 4 × 3 matrixes.

8. multifrequency terahertz imaging system according to claim 5, is characterized in that,

Described multiple detector array is in line type.

9. multifrequency terahertz imaging system according to claim 5, is characterized in that,

Described multiple detector lines up multirow stragglyly.

10. multifrequency terahertz imaging system according to claim 9, is characterized in that,

When 12 detectors of use three kinds of frequencies, the detector of often kind of frequency are 4, described 12 detector array become three row, and middle row differs the distance of the width of half detector with upper and lower two row.