阅读说明：本技术 一种用于太赫兹频段的准直聚焦系统 (A kind of collimation focusing system for Terahertz frequency range ) 是由 郝丛静 侯培培 李世超 刘瑞强 贾渠 于 2019-08-02 设计创作，主要内容包括：本发明实施例提供了一种用于太赫兹频段的准直聚焦系统,本发明应用于安检成像系统中。本发明涉及安检领域,该系统包括：馈源,发出的波束沿Z方向传播,波束的X方向在近距离范围内为平行波束,在Y方向为发散波束；准直器件,用于对发散波束准直；聚焦器件,用于对准直后得到的新波束聚焦；成像面器件,用于接收经过准直、聚焦后的聚焦光斑。本发明提供的一种用于太赫兹频段的准直聚焦系统,解决了现有太赫兹安检成像系统中波束在不同方向发散程度不一样引起聚焦位置偏差从而导致成像分辨率差的问题。实现了波束聚焦位置相同、聚焦光斑效果较好的状态,从而使安检成像系统的成像器件相比现有技术成像分辨率更加高、性能更好的效果。(The embodiment of the invention provides a kind of collimation focusing system for Terahertz frequency range, the present invention is applied in safety check imaging system.The present invention relates to field of safety check, which includes: feed, and the wave beam of sending is propagated along Z-direction, and it is in the Y direction divergent beam that the X-direction of wave beam, which is parallel beam in short range,；Collimating element, for being collimated to divergent beam；Focus device, the new wave beam for obtaining after collimation focus；Imaging surface device, for receiving the focal beam spot after collimating, focusing.A kind of collimation focusing system for Terahertz frequency range provided by the invention solves the problems, such as in existing Terahertz safety check imaging system that wave beam causes focal position deviation poor so as to cause imaging resolution different directions degree of divergence is different.Realize that beam focal position is identical, the preferable state of focal beam spot effect, thus make the image device of safety check imaging system compared with prior art imaging resolution more increase, the better effect of performance.)

1. a kind of collimation focusing system for Terahertz frequency range, the system is applied in safety check imaging system, comprising:

Feed, the wave beam of sending are parallel beam in short range in X-direction, are in the Y direction divergent beam；

Collimating element, for being collimated to divergent beam；

Focus device, the new wave beam for obtaining after collimation focus；

Imaging surface device, the focal beam spot for being formed after collectiong focusing.

2. collimation focusing system according to claim 1, which is characterized in that the collimating element is cylindrical lens or paraboloid Mirror.

3. collimation focusing system according to claim 1, which is characterized in that the focus device is condenser lens.

4. collimation focusing system according to claim 1, which is characterized in that the wave beam of the new wave beam obtained after the collimation Radius is identical as the wave beam radius of the parallel beam.

5. collimation focusing system according to claim 1, which is characterized in that the received focusing of imaging surface device Size is identical in vertical direction for hot spot.

6. collimation focusing system according to claim 1, which is characterized in that the wave beam that the feed issues is THz wave Beam or millimeter wave wave beam.

7. a kind of safety check imaging system characterized by comprising

Any collimation focusing system of claim 1-6；

Image device is used to provide the described imaging surface.

Technical field

The present invention relates to field of safety check, the collimation focusing system of especially a kind of Terahertz frequency range for safety check imaging.

Background technique

Since in June, 2018, civil aviation authority has promulgated the standard and detectivity test of corresponding millimeter wave human body safety check equipment The demand of human body safety check equipment is substantially improved in program, public safety field of traffic and Code in Hazardous Special Locations.Public safety problem according to It is old at home and abroad in occupation of important position, and in face of at present always in the metal detector gate of application, hand-held safety check and artificial There is certain drawbacks for the human bodies security actions such as hand inspection, are unable to some potential nonmetallic concealment contrabands of efficient detection, danger Dangerous article etc..And all exist for health and individual privacy of the radiativities such as X-ray rays safety detection apparatus to examinee certain Problem, therefore millimeter wave, THz wave human body safety check imaging system are needed by market, respectively research universities and colleges, enterprise are constantly complete Design in kind human body safety check imaging system allows equipment to complete human body safety check work with optimal performance, thus for public affairs Security fields provide a reliable guarantee altogether.

The THz wave that the feed of the instrument equipment of THz wave safety check at present is radiated is in free space according to Gaussian beam Characteristic is propagated, if the rays safety detection apparatus does not take collimation or focuses measure, the wave beam that feed issues can hair sharply It dissipates, and excessive entrance pupil is extremely difficult for optical optimization design, while the lens processing and manufacturing of electrically large sizes is also relatively difficult.

Safety check imaging system is contained in THz wave safety check instrument equipment, before Quasi optics are the safety check imaging system End, the performance focused directly affect the effect being ultimately imaged.Currently, Quasi optics are to radiation beam in orthogonal directions When focusing for the wave beam of different degrees of divergence, final focusing can be realized using the focus lamp of different directions, but meeting There are focal positions there are the transmission situation that the condenser lens of deviation, different directions influences direction wave beam normal thereto, finally leads Cause the resolution ratio of imaging bad.

Summary of the invention

In view of the above problems, the present invention provides a kind of collimation focusing system for Terahertz frequency range, solve it is existing too Wave beam causes focal position deviation so as to cause imaging point different directions degree of divergence is different in hertz safety check imaging system The problem of resolution difference.

The present invention is achieved through the following technical solutions:

In a first aspect, the system is applied in safety check imaging system the invention discloses a kind of collimation focusing system, packet It includes:

Feed, the wave beam of sending are parallel beam in short range in X-direction, are in the Y direction divergent beam；

Collimating element, for being collimated to divergent beam；

Focus device, the new wave beam for obtaining after collimation focus；

Imaging surface device, the focal beam spot for being formed after collectiong focusing.

Preferably, the wave beam radius of the new wave beam obtained after the collimation and the wave beam radius of the parallel beam are identical.

Preferably, size is identical in vertical direction for the received focal beam spot of the imaging surface device.

Preferably, the wave beam that the feed issues is terahertz wave beam or millimeter wave wave beam.

Second aspect, the invention discloses a kind of safety check imaging systems, comprising:

Any collimation focusing system in first aspect；

Image device is used to provide the described imaging surface.

Compared with prior art, the present invention includes the following advantages:

The present invention carries out collimation processing, the wave after collimation processing with Y-direction of the collimating element to the wave beam that emission source emits Beam Y-direction is directional light, effective guarantee consistency of the wave beam in focusing as the beam angle of X-direction；With Treated that wave beam is focused processing for the same focus device collimation, obtains both direction in imaging surface device same position The identical focal beam spot of spot size, realizes that beam focal position is identical, the preferable state of focal beam spot effect, to make to pacify Examine imaging system image device compared with prior art imaging resolution more increase, the better effect of performance.

Detailed description of the invention

By reading the following detailed description of the preferred embodiment, various other advantages and benefits are common for this field Technical staff will become clear.The drawings are only for the purpose of illustrating a preferred embodiment, and is not considered as to the present invention Limitation.And throughout the drawings, the same reference numbers will be used to refer to the same parts.In the accompanying drawings:

Fig. 1 is terahertz wave beam collimation focusing light path schematic diagram of the present invention；

Fig. 2 is the outside drawing of collimating lens, focusing lens of the present invention；

Fig. 3 is the schematic device of the collimation focusing system of safety check imaging system of the present invention.

Specific embodiment

In order to make the foregoing objectives, features and advantages of the present invention clearer and more comprehensible, with reference to the accompanying drawing and specific real Applying mode, the present invention is described in further detail.It should be appreciated that specific embodiment described herein is only to explain this Invention, only a part of the embodiment of the present invention is not intended to limit the present invention instead of all the embodiments.

It is terahertz wave beam collimation focusing light path schematic diagram of the present invention with reference to Fig. 1.(a), (b) figure are different perspectivess in Fig. 1 The Computer analogue diaram that lower wave beam is propagated in Z-direction, i.e., the cross-sectional view of different sides in 3-D image, for describing terahertz wave beam Collimation focusing optical path, which, which reflects wave beam, the characteristic of different degrees of divergence or the spy of different beams radius in X, Y-direction Property.(a), (b) figure are light path schematic diagram of the same wave beam under different perspectives in Fig. 1.Wherein, Fig. 1 (a) is the face xoz section view Figure, i.e. X-direction collimation focusing schematic diagram, Fig. 1 (b) are the face yoz cross-sectional view, i.e. Y-direction collimation focusing schematic diagram.This two width figure is equal It is the cross-sectional view that a three-dimensional simulation figure rotates to both direction difference vision respectively.As shown in Fig. 1 (a), which is the face xoz View.Because wave beam propagates less parallel in X-direction, parallel beam can be regarded as in short range, so the figure can only be seen The light path schematic diagram first focused again by focus device in the form of less parallel wave by collimating element to wave beam.Such as Fig. 2 (b) Shown, which is the view in the face yoz.Because the wave beam is divergent shape in the Y direction, can regard as diverging wave, so can from figure See that wave beam is entered collimating element in the form of diverging wave and becomes parallel beam, then is illustrated by the optical path that focus device focuses Figure.It especially reminds because the focusing distance of Fig. 1 focus device is much larger than the distance between focus device and collimating element, sees Enlarged drawing is asked to be checked when figure.

It is the schematic device of the collimation focusing system of safety check imaging system of the present invention with reference to Fig. 3.The collimation focusing system It applied in safety check imaging system, and is the front end of safety check imaging system.The collimation focusing system is by beam source 301, collimator Part 302, focus device form 303, imaging surface device 304.

Feed 301 is for generating millimeter wave or THz wave, and the wave is passed according to Gaussian beam characteristic in free space It broadcasts.The direction of propagation of wave beam is Z-direction.For the wave beam in terms of X-direction, i.e. the face the xoz sectional view of wave beam sees that the wave beam is in X-direction From being parallel beam in 301 short range of beam source, referring to Fig.1 (a).In terms of Y-direction, i.e. the face the yoz sectional view of wave beam is seen, The wave beam is divergent beam in the Y direction, referring to Fig.1 (b).Meanwhile X-direction is bigger compared to the beam angle of Y-direction, i.e. the wave beam Y-direction is faster than the diverging of X-direction, it is therefore desirable to by Y-direction beam collimation at beam angle identical with X-direction.Feed at present Selection there are many 301, such as: radiating horn antenna, array antenna, Waveguide slot antenna etc., with no restrictions to this present invention.

Collimating element 302 is used to divergent beam becoming parallel wave.Collimating element 302 is used for feed 301 in the present embodiment The wave beam of sending is in that the wave beam of divergent shape carries out collimation processing in the Y direction, i.e., is processed into the Y-direction diverging form of wave beam flat Traveling wave form.The Y-direction that feed 301 issues wave beam has been changed to and the wave beam X-direction homomorphosis after collimating element 302 Collimation treated wave beam, i.e. Y-direction becomes parallel wave, meanwhile, by the wave beam of the Y-direction for the wave beam that collimates that treated Radius is identical as the wave beam radius of X-direction, and wavefront is plane, identical as X-direction.It should be noted that wave beam of the present invention passes through The beam angle of X-direction, wavefront form will not change after collimating element 302.In the present embodiment, collimating element 302 is Cylindrical lens (shown in such as Fig. 2 (a)) or paraboloidal mirror, the preferred cylindrical lens of the present embodiment.The material of the lens is high density polyethylene (HDPE) Or the material that the millimeter waves such as polytetrafluoroethylene (PTFE), Terahertz wave height are saturating.

The new wave beam that focus device 303 is used to obtain after collimation focuses.In the present embodiment, the new wave beam that is obtained after collimation Processing is focused by focus device 303, the ruler of the focal beam spot of 304 same position of imaging surface device in X and Y-direction hot spot It is very little identical.Focus device 303 is condenser lens (shown in such as Fig. 2 (b)) in the present embodiment, and the material of the condenser lens can be highly dense Spend the saturating material of the millimeter waves such as polyethylene or polytetrafluoroethylene (PTFE), Terahertz wave height.

Imaging surface device 304 is used for the focal beam spot formed after collectiong focusing.In the present embodiment, the imaging surface device 304 It can be imaging surface.The imaging surface device is then tested in actual imaging system for the focusing effect that Gaussian beam is presented The position of human body, the characteristic with reflected beam.

It can be seen from the above technical proposal that present embodiments providing a kind of collimation focusing system, it is applied to safety check and is imaged In system, which includes feed, collimating element, focus device, imaging surface device.All wave beams that beam source issues all are edges Z-direction co-propagate.Each wave beam passes through collimating element first and becomes parallel beam, and collimation lens is mainly for the side Y herein To the wave beam of diverging, the wave beam that Y-direction dissipates is changed to parallel beam by collimating element, and the beam angle of the wave beam is changed At as the wave beam of X-direction, i.e. wave beam radius is identical, meanwhile, the wave beam that feed issues in terms of X-direction is passing through collimating element Enter the beam angle and constant into the beam angle before collimating element before focus device afterwards, wavefront form is also unchanged；By standard Straight device treated wave beam is focused processing by focus device, and the focal beam spot of treated wave beam is in reception image planes device Identical size is presented on part same position X, Y-direction.The present embodiment realize receive image planes device same position focal beam spot compared with It is good, the identical effect of hot spot both direction size, so as to so that the imaging of safety check imaging system reaches preferable level.

For the focusing of clearer description wave beam of the present invention, the preferred feed antenna sending Terahertz of the present embodiment The focusing of wave, specific focusing are as follows:

Feed antenna issues terahertz wave beam, which shows the characteristic of parallel wave in X-direction, show in the Y direction Divergence characterization.Away from cylindrical lens central line distance 600mm, feed antenna issues terahertz wave beam to be passed through feed antenna, that is, emission source Cylindrical lens carry out collimation processing, and the wave beam that diverging is presented in Y-direction is become the parallel beam as X-direction presentation characteristic, Meanwhile the wave beam radius of the wave beam Y-direction and the wave beam radius of the wave beam X-direction are identical after collimation.Because the wave beam is by quasi- The wave beam Y-direction is is rendered as parallel wave state after straight processing, therefore the distance of cylindrical lens and condenser lens in the present embodiment Without limitation, the linear distance of condenser lens center and reception image plane center is 2000mm, i.e. the focusing distance of condenser lens is 2000mm.For the beam propagation by collimation processing to condenser lens, condenser lens is focused processing to the wave beam, is receiving Image planes show same position X, the identical focal beam spot of Y-direction size.The bore of cylindrical lens and condenser lens in the present embodiment It is 500 × 500mm.

The advantages of the present embodiment has: collimating element carries out collimation processing to the Y-direction for the wave beam that emission source emits, at collimation The wave beam Y-direction is as the beam angle of X-direction after reason, and be parallel wave, and effective guarantee wave beam is in focusing Consistency；With the same focus device collimation, treated that wave beam is focused processing, obtains in imaging surface device same position To the identical focal beam spot of both direction size, realize that beam focal position is identical, the preferable state of focal beam spot effect, from And make the image device of safety check imaging system compared with prior art imaging resolution more increase, the better effect of performance.

Based on the above embodiment, a kind of safety check imaging system is disclosed in an alternative embodiment of the invention.The system includes The collimation focusing system and image device of safety check imaging system in above-described embodiment.

Wherein, identical in collimation focusing system and above-described embodiment, it does not illustrate herein.Image device includes: reception day Line, the image processing apparatus with receiving antenna communication connection.

Receiving antenna is used to receive the microwave or terahertz wave signal of reflection, and exports microwave or THz wave amplitude letter Breath.

Image processing apparatus is used to receive the microwave of receiving antenna output or the amplitude information of THz wave, using based on area The relevant stitching algorithm in domain is based on the relevant stitching algorithm of feature, the microwave or THz wave of the secondary test sample of final synthesis one Reflected image.The reflected image characterizes the radiation intensity of human body or each position THz wave of other articles or microwave.For example, people When keeping gun, cutter and other items in the clothing worn, the terahertz radiation intensity of article position and human body other There is strong and weak comparison in position, gray difference is shown as on reflected image, realize the detection to hidden article.

In the present embodiment, which first carries out standard to microwave or terahertz wave beam by collimation focusing system Straight processing, refocusing hot spot, finally at reflected image in image device, so that the reflected image of the safety check imaging system is differentiated Rate is more increased compared with prior art.Meanwhile the safety check imaging system has used microwave or terahertz wave beam, enables the system high Effect detection some potential nonmetallic concealment contraband, dangerous goods etc., and the radiativities such as X-ray are pacified compared to the prior art Inspection equipment more protects the privacy and safety of people.

Above to a kind of collimation focusing system for Terahertz frequency range provided by the present invention, it is described in detail, Used herein a specific example illustrates the principle and implementation of the invention, and the explanation of above embodiments is only used In facilitating the understanding of the method and its core concept of the invention；At the same time, for those skilled in the art, according to the present invention Thought, there will be changes in the specific implementation manner and application range, in conclusion the content of the present specification should not be construed as Limitation of the present invention.