CN110297418A - A kind of THz wave digital hologram imaging method decomposed based on Terahertz diffraction pattern - Google Patents
A kind of THz wave digital hologram imaging method decomposed based on Terahertz diffraction pattern Download PDFInfo
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- 235000017166 Bambusa arundinacea Nutrition 0.000 description 1
- 235000017491 Bambusa tulda Nutrition 0.000 description 1
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- G03H—HOLOGRAPHIC PROCESSES OR APPARATUS
- G03H1/00—Holographic processes or apparatus using light, infrared or ultraviolet waves for obtaining holograms or for obtaining an image from them; Details peculiar thereto
- G03H1/04—Processes or apparatus for producing holograms
- G03H1/0443—Digital holography, i.e. recording holograms with digital recording means
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- G—PHYSICS
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- G03H—HOLOGRAPHIC PROCESSES OR APPARATUS
- G03H1/00—Holographic processes or apparatus using light, infrared or ultraviolet waves for obtaining holograms or for obtaining an image from them; Details peculiar thereto
- G03H1/04—Processes or apparatus for producing holograms
- G03H1/08—Synthesising holograms, i.e. holograms synthesized from objects or objects from holograms
- G03H1/0866—Digital holographic imaging, i.e. synthesizing holobjects from holograms
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- G03H—HOLOGRAPHIC PROCESSES OR APPARATUS
- G03H1/00—Holographic processes or apparatus using light, infrared or ultraviolet waves for obtaining holograms or for obtaining an image from them; Details peculiar thereto
- G03H1/04—Processes or apparatus for producing holograms
- G03H1/10—Processes or apparatus for producing holograms using modulated reference beam
- G03H1/12—Spatial modulation, e.g. ghost imaging
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- G—PHYSICS
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- G03H—HOLOGRAPHIC PROCESSES OR APPARATUS
- G03H1/00—Holographic processes or apparatus using light, infrared or ultraviolet waves for obtaining holograms or for obtaining an image from them; Details peculiar thereto
- G03H1/22—Processes or apparatus for obtaining an optical image from holograms
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- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03H—HOLOGRAPHIC PROCESSES OR APPARATUS
- G03H1/00—Holographic processes or apparatus using light, infrared or ultraviolet waves for obtaining holograms or for obtaining an image from them; Details peculiar thereto
- G03H1/0005—Adaptation of holography to specific applications
- G03H2001/0088—Adaptation of holography to specific applications for video-holography, i.e. integrating hologram acquisition, transmission and display
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Abstract
The invention discloses a kind of THz wave digital hologram imaging methods decomposed based on Terahertz diffraction pattern, including Terahertz hologram record, hologram to propagate in advance, pre- to propagate the picture breakdown of diffraction surfaces complex amplitude and stage construction complex amplitude image reconstruction synthesis process.Wherein: (1) Terahertz hologram recording process: acquisition process obtains large aperture normalization Terahertz hologram in Terahertz digital holographic imaging systems.(2) the pre- communication process of hologram: Free propagation specific range obtains the pre- complex amplitude image for propagating diffraction surfaces.(3) diffraction surfaces complex amplitude picture breakdown process is propagated in advance: calculating pre- propagation diffraction surfaces complex amplitude display foreground face and background face threshold value, makes binaryzation mask image, obtains the pre- sub- complex amplitude image for propagating diffraction surfaces.(4) stage construction complex amplitude image reconstruction synthesis process: rebuilding the sub- complex amplitude image of each object plane, and synthesis obtains THz wave digital hologram multiple slice imaging result.
Description
Technical field
The present invention relates to THz wave digital hologram multiple slice imaging method and technology fields, specially a kind of to be based on Terahertz
The THz wave digital hologram imaging method that diffraction pattern decomposes.
Background technique
Terahertz wave band because in it is infrared arrive microwave transition wave band due to have both the two characteristic, be allowed to answer in imaging field
With having a extensive future, and Digital Holography because of its imaging arrangement simply and flexible data processing method, to specific objective sample
Multiple focusing levels imaging have unique advantage.In traditional imaging process, there are sample distributions in multiple focusing distances and
The problem of required multi-focus level detection result can not be obtained, Terahertz Digital Holography can give full play to the advantage of the two
And feature, become a kind of realization multi-focus level imaging technique in terahertz wave band.
The present invention is directed to propose a kind of THz wave digital hologram Stratified Imaging method decomposed based on diffraction pattern.This is one
Item passes through list by computer to the digital process of Terahertz hologram in the novel imaging technique of terahertz wave band
The THz wave hologram of secondary record by imaging sample can be obtained the amplitude and phase that sample includes different depth direction focusing face
Information.Compared to traditional THz wave imaging means, which measures without mechanical adjustment focusing surface position and multiple exposure, i.e.,
The stage construction complex amplitude detection imaging of sample can be achieved.It, should in conjunction with the selective permeability and lossless safety of THz wave itself
Invention is that one kind can penetrate nonmetallic nonpolar cloak, and different depth focusing surface information can be realized in single record exposure
Imaging technique can be widely used in lossless detection and material characterization field.
Summary of the invention
The purpose of the present invention is to provide a kind of THz wave digital hologram imaging sides decomposed based on Terahertz diffraction pattern
Method obtains the complex amplitude of target sample different depth focusing surface to solve prior art deficiency mentioned above in the background art
Information realizes the stage construction complex amplitude imaging of sample.
To achieve the above object, the invention provides the following technical scheme: a kind of terahertz decomposed based on Terahertz diffraction pattern
Hereby wave number word holographic imaging method, comprising the following steps: Terahertz hologram recording process, the pre- communication process of hologram are pre- to pass
Diffraction surfaces complex amplitude picture breakdown process is broadcast, stage construction complex amplitude image reconstruction synthesis process:
(1) Terahertz hologram recording process.Sample on depth direction comprising stage construction information is placed in Terahertz
In digital holographic imaging systems, THz wave is modulated by sample, is carried the stage construction information of sample, is modulated with without sample
Terahertz with reference to wave interference formed Terahertz hologram.To improve system imaging resolution ratio, the two of terahertz detector are carried
It ties up translation stage and carries out two-dimensional movement, acquisition according to given scanning sequency in the record plane perpendicular to THz wave illumination direction
The Terahertz sub-hologram of different location.After removing sample, the two-dimension translational platform of terahertz detector is carried according to Terahertz
Identical scanning sequency during hologram record, records the sub- background image of Terahertz.The correspondence terahertz that same position is acquired
Hereby sub-hologram and the sub- Background of Terahertz are divided by, and obtain sub- normalization hologram, and it is complete to carry out son normalization according to scanning sequency
Figure image mosaic is ceased, large aperture normalization Terahertz hologram is obtained.
(2) the pre- communication process of hologram.Large aperture normalization Terahertz hologram in step (1) is led in a computer
Free-space propagation algorithm is crossed, propagates to diffraction plane P in advance along object plane direction, obtains the pre- amplitude and phase for propagating diffraction surfaces
Bit distribution propagates diffraction surfaces complex amplitude image U (m, n) in advance.The propagation distance of the diffraction surfaces is dp.Define the layering of sample difference
Maximum distance of the identity distance from terahertz detector record plane and minimum range are respectively dmaxAnd dmin, then dpValue be defined as
(3) diffraction surfaces complex amplitude picture breakdown process is propagated in advance.The pre- propagation diffraction surfaces complex amplitude image U of calculating extraction (m,
N) amplitude and phase image carry out the judgement of the maximum variance threshold value T in foreground facets and background face using maximum variance between clusters
It calculates, the pre- binaryzation operation for propagating diffraction surfaces complex amplitude image is carried out based on obtained threshold value T, obtains binaryzation mask image
K (m, n), is represented by
Mean value Fuzzy processing in edge is completed to binaryzation mask image K (m, n), obtains the pre- exposure mask figure for propagating diffraction surfaces
As K ' (m, n), by nonzero value region recognition, to x isolated nonzero value area images in mask image K ' (m, n) carry out by
One extracts, and by its zero padding value to the Pixel Dimensions size of former mask image K ' (m, n), it is a only non-comprising individually isolating to obtain x
The sub- mask image K ' of zero image-regioni(i=1,2 ..., x).By obtained x sub- mask image K 'iIt is propagated respectively with pre-
The complex amplitude image U of diffraction surfaces is multiplied, and obtains the x pre- sub- complex amplitude image U for propagating diffraction surfacesi(i=1,2 ..., x).
Ui=U × K'i, i=1,2 ..., x
(4) stage construction complex amplitude image reconstruction synthesis process.The each of pre- propagation diffraction surfaces is calculated by auto-focusing algorithm
A sub- complex amplitude image UiFocusing propagation distance, and propagated by free-space propagation algorithm, reconstruction obtains each object
Plane complex amplitude image Oi(i=1,2 ..., x).By each object plane complex amplitude image OiRespectively with corresponding sub- exposure mask
Image K 'iMultiplication obtains image O 'i, calculate each object plane complex amplitude image OiAverage valueAnd with pair that negates operation
Answer sub- mask image (1-K 'i) being multiplied obtains image O "i, by image O 'iWith image O "iThe stage construction of additional combining target sample
Complex amplitude imaging results O, the step are represented by
Preferably, the side output of the avalanche diode Terahertz wave source has THz wave, and avalanche diode terahertz
Hereby the side of wave source towards THz wave is provided with sample, and the THz wave pyroelectric detector is installed on the end of THz wave
End, and detector two-dimension translational platform is fixed with below THz wave pyroelectric detector.
Preferably, the structure of the avalanche diode Terahertz wave source, sample and THz wave pyroelectric detector is too
The coaxial imaging system of hertz.
Preferably, the pre- propagation diffraction surfaces complex amplitude picture breakdown process extracts pre- propagate and spreads out for amplitude type sample
The distribution of amplitudes image for penetrating face extracts the pre- phase distribution image for propagating diffraction surfaces for phase type sample.
It is and existing the present invention provides a kind of THz wave digital hologram imaging method decomposed based on Terahertz diffraction pattern
Technology is compared, and beneficial effects of the present invention are as follows:
The present invention provides a kind of THz wave digital hologram Stratified Imaging methods decomposed based on diffraction pattern, pass through the hair
Bright method and system, to Terahertz hologram carry out digital processing, can non-contact, lossless acquisitions target sample different depth gather
The complex amplitude information of focal plane realizes that sample is imaged in the stage construction complex amplitude of terahertz wave band, and practicability is extensive.
Detailed description of the invention
Fig. 1 is a kind of process of the THz wave digital hologram imaging method decomposed based on Terahertz diffraction pattern of the present invention
Figure；
Fig. 2 is a kind of showing for THz wave digital hologram Stratified Imaging system decomposed based on Terahertz diffraction pattern of the present invention
It is intended to.
In figure: 1, avalanche diode Terahertz wave source；1a, THz wave；2, sample；3, detector two-dimension translational platform；4,
THz wave pyroelectric detector.
Specific embodiment
Below in conjunction with the data in the embodiment of the present invention, technical solution in the embodiment of the present invention carries out clear, complete
Site preparation description, it is clear that described embodiments are only a part of the embodiments of the present invention, instead of all the embodiments.
The present invention provides a kind of technical solution referring to FIG. 1-2: a kind of THz wave decomposed based on Terahertz diffraction pattern
Digital hologram imaging method, comprising the following steps:
(1) Terahertz hologram recording process.Sample on depth direction comprising stage construction information is placed in Terahertz
In digital holographic imaging systems, THz wave is modulated by sample, is carried the stage construction information of sample, is modulated with without sample
Terahertz with reference to wave interference formed Terahertz hologram.To improve system imaging resolution ratio, the two of terahertz detector are carried
It ties up translation stage and carries out two-dimensional movement, acquisition according to given scanning sequency in the record plane perpendicular to THz wave illumination direction
The Terahertz sub-hologram of different location.After removing sample, the two-dimension translational platform of terahertz detector is carried according to Terahertz
Identical scanning sequency during hologram record, records the sub- background image of Terahertz.The correspondence terahertz that same position is acquired
Hereby sub-hologram and the sub- Background of Terahertz are divided by, and obtain sub- normalization hologram, and it is complete to carry out son normalization according to scanning sequency
Figure image mosaic is ceased, large aperture normalization Terahertz hologram is obtained.
(2) the pre- communication process of hologram.Large aperture normalization Terahertz hologram in step (1) is led in a computer
Free-space propagation algorithm is crossed, propagates to diffraction plane P in advance along object plane direction, obtains the pre- amplitude and phase for propagating diffraction surfaces
Bit distribution propagates diffraction surfaces complex amplitude image U (m, n) in advance.The propagation distance of the diffraction surfaces is dp.Define the layering of sample difference
Maximum distance of the identity distance from terahertz detector record plane and minimum range are respectively dmaxAnd dmin, then dpValue be defined as
(3) diffraction surfaces complex amplitude picture breakdown process is propagated in advance.For amplitude type sample, the pre- vibration for propagating diffraction surfaces is extracted
Width distributed image extracts the pre- phase distribution image for propagating diffraction surfaces for phase type sample.It calculates and extracts pre- propagation diffraction surfaces
The amplitude and phase image of complex amplitude image U (m, n) carries out the most generous of foreground facets and background face using maximum variance between clusters
The judgement of poor threshold value T calculates, and carries out the pre- binaryzation operation for propagating diffraction surfaces complex amplitude image based on obtained threshold value T, obtains
Binaryzation mask image K (m, n), is represented by
Mean value Fuzzy processing in edge is completed to binaryzation mask image K (m, n), obtains the pre- exposure mask figure for propagating diffraction surfaces
As K ' (m, n), by nonzero value region recognition, to x isolated nonzero value area images in mask image K ' (m, n) carry out by
One extracts, and by its zero padding value to the Pixel Dimensions size of former mask image K ' (m, n), it is a only non-comprising individually isolating to obtain x
The sub- mask image K ' of zero image-regioni(i=1,2 ..., x).By obtained x sub- mask image K 'iIt is propagated respectively with pre-
The complex amplitude image U of diffraction surfaces is multiplied, and obtains the x pre- sub- complex amplitude image U for propagating diffraction surfacesi(i=1,2 ..., x).
Ui=U × K'i, i=1,2 ..., x
(4) stage construction complex amplitude image reconstruction synthesis process.The each of pre- propagation diffraction surfaces is calculated by auto-focusing algorithm
A sub- complex amplitude image UiFocusing propagation distance, and propagated by free-space propagation algorithm, reconstruction obtains each object
Plane complex amplitude image Oi(i=1,2 ..., x).By each object plane complex amplitude image OiRespectively with corresponding sub- exposure mask
Image K 'iMultiplication obtains image O 'i, calculate each object plane complex amplitude image OiAverage valueAnd with pair that negates operation
Answer sub- mask image (1-K 'i) being multiplied obtains image O "i, by image O 'iWith image O "iThe stage construction of additional combining target sample
Complex amplitude imaging results O, the step are represented by
A kind of THz wave digital hologram imaging method decomposed based on Terahertz diffraction pattern, including avalanche diode terahertz
Hereby wave source 1, THz wave 1a, detector two-dimension translational platform 3 and THz wave pyroelectric detector 4, avalanche diode Terahertz
The side output of wave source 1 has THz wave 1a, and avalanche diode Terahertz wave source 1 is provided with towards the side of THz wave 1a
Sample 2, THz wave pyroelectric detector 4 are installed on the end of THz wave 1a, and under THz wave pyroelectric detector 4
Side is fixed with detector two-dimension translational platform 3, avalanche diode Terahertz wave source 1, sample 2 and THz wave pyroelectric detector 4
Structure be the coaxial imaging system of Terahertz, avalanche diode Terahertz wave source 1 is detected producing and exporting THz wave 1a
Device two-dimension translational platform 3 completes the Two-dimensional Position in detector scanning and recording process for placing THz wave pyroelectric detector 4
It moves, THz wave pyroelectric detector 4 is to acquire Terahertz hologram and background image.
To sum up, the THz wave digital hologram imaging method that should be decomposed based on Terahertz diffraction pattern, in use, including following
Step:
(1) Terahertz hologram recording process.Target sample is the metal needle in the depth direction including stage construction information
With asparagus fern.Sample is placed in Terahertz digital holographic imaging systems, THz wave is modulated by sample, carries the more of sample
Section information forms Terahertz hologram with reference to wave interference with the Terahertz modulated without sample.To improve system imaging
Resolution ratio, carry the two-dimension translational platform of terahertz detector in the record plane perpendicular to THz wave illumination direction according to
Determine rectangular scanning sequence and carry out two-dimensional movement, acquires the Terahertz sub-hologram of nine different locations.After removing sample, carry too
The two-dimension translational platform of hertz detector records corresponding nine according to identical scanning sequency in Terahertz sub-hologram recording process
The sub- background image of width Terahertz.The correspondence Terahertz sub-hologram of same position acquisition and the sub- Background of Terahertz are divided by, obtained
Hologram is normalized to nine width, son normalization holographic image splicing is carried out according to scanning sequency, obtains a width laboratory sample
Large aperture normalize Terahertz hologram.
(2) the pre- communication process of hologram.Large aperture normalization Terahertz hologram in step (1) is led in a computer
Free-space propagation algorithm is crossed, propagates to diffraction plane in advance along needle and asparagus fern in-plane, obtains the pre- amplitude for propagating diffraction surfaces
And phase distribution, i.e., diffraction surfaces complex amplitude image U (m, n) is propagated in advance, wherein m≤320, n≤320.Sample difference is layered identity distance
Maximum distance and minimum range from terahertz detector record plane are respectively dmax=65mm and dmin=45mm, the then diffraction
The propagation distance d in facepTake the two average value, i.e. dp=55mm.
(3) diffraction surfaces complex amplitude picture breakdown process is propagated in advance.The pre- propagation diffraction surfaces complex amplitude image U of calculating extraction (m,
N) amplitude and phase image carry out the judgement meter of the maximum variance threshold value in foreground facets and background face using maximum variance between clusters
It calculates, obtaining threshold value is 0.8118, carries out the pre- binaryzation operation for propagating diffraction surfaces complex amplitude image based on obtained threshold value, obtains
Binaryzation mask image K (m, n), is represented by
Mean value Fuzzy processing in edge is completed to binaryzation mask image K (m, n), obtains the pre- exposure mask figure for propagating diffraction surfaces
It is to 2 isolated nonzero value area images in mask image K ' (m, n), i.e., literary by nonzero value region recognition as K ' (m, n)
Bamboo region image and metal needle region image, are extracted one by one, and by its zero padding value to former mask image K ' (m,
N) Pixel Dimensions size 320 × 320 obtains sub- exposure mask figure K ' only comprising asparagus fern region1, only include metal needle region son
Exposure mask figure K '2.By K '1、K′2It is multiplied respectively with the pre- complex amplitude image U for propagating diffraction surfaces, obtains containing only for pre- propagation diffraction surfaces
There is the sub- complex amplitude image U of asparagus fern regional location1With pre- propagation diffraction surfaces only containing the sub- complex amplitude of metal needle regional location
Image U2。
(4) stage construction complex amplitude image reconstruction synthesis process.Pre- propagation diffraction surfaces are calculated by auto-focusing algorithm
Sub- complex amplitude image U1、U2Focusing propagation distance be respectively -5mm and 5mm.It is propagated by free-space propagation algorithm,
Reconstruction obtains each object plane complex amplitude image O1、O2.By object plane complex amplitude image O1、O2It is covered respectively with corresponding son
Film image K '1、K′2Multiplication obtains image O '1、O′2, calculate each object plane complex amplitude image O1、O2Average value
And with the corresponding sub- mask image (1-K ' that negates operation1)、(1-K′2) being multiplied obtains image O "1、O″2, by image O '1、O′2
With image O "1、O″2The stage construction complex amplitude imaging results O of additional combining target sample, metal needle is with asparagus fern in image O
Clear image when focusing propagation distance, the step are represented by
Imaging system optical path of the invention is formed as shown in Fig. 2, being produced and exported using avalanche diode Terahertz wave source 1
THz wave 1a, wherein 1 central wavelength of wave source is 300mm, frequency 0.1THz；Detector two-dimension translational platform 3 is for placing too
Hertz wave pyroelectric detector 4 completes the two-dimension displacement in detector scanning and recording process；THz wave pyroelectric detector
4 pixel separations are 80 μm, and Pixel Dimensions are that 160 pixels are completed like this to acquire Terahertz hologram image and background image
The use process of the THz wave digital hologram imaging method entirely decomposed based on Terahertz diffraction pattern.
It is complete that the mentioned invention of the results show of exemplary embodiments of the invention can effectively realize THz wave number
Multiple slice imaging is ceased, the complex amplitude information of target sample different depth focusing surface is obtained.Although being retouched in detail with reference to specific embodiment
The present invention is stated, invention described herein embodiment, which is not intended to, to be detailed or be confined to disclosed concrete form.
On the contrary, selected embodiment for illustration is selected to make those skilled in the art implement the present invention
's.In the case where not departing from the essential scope of the invention described by claim and limited, there are variations and modifications.
Claims (4)
1. a kind of THz wave digital hologram imaging method decomposed based on Terahertz diffraction pattern, comprising the following steps: Terahertz
Hologram recording process, the pre- communication process of hologram are pre- to propagate diffraction surfaces complex amplitude picture breakdown process, stage construction complex amplitude figure
As rebuilding synthesis process:
(1) Terahertz hologram recording process.Sample on depth direction comprising stage construction information is placed in Terahertz number
In holographic imaging systems, THz wave is modulated by sample, is carried the stage construction information of sample, is modulated too with without sample
Hertz forms Terahertz hologram with reference to wave interference.To improve system imaging resolution ratio, the two dimension for carrying terahertz detector is flat
Moving stage carries out two-dimensional movement according to given scanning sequency in the record plane perpendicular to THz wave illumination direction, and acquisition is different
The Terahertz sub-hologram of position.After removing sample, the two-dimension translational platform for carrying terahertz detector is holographic according to Terahertz
Identical scanning sequency during seal record, records the sub- background image of Terahertz.By correspondence Terahertz of same position acquisition
Hologram and the sub- Background of Terahertz are divided by, and obtain sub- normalization hologram, carry out son normalization hologram according to scanning sequency
Image mosaic obtains large aperture normalization Terahertz hologram.
(2) the pre- communication process of hologram.Large aperture normalization Terahertz hologram in step (1) is passed through certainly in a computer
By spatial algorithm, diffraction plane P is propagated in advance along object plane direction, obtains the pre- amplitude for propagating diffraction surfaces and phase point
Cloth propagates diffraction surfaces complex amplitude image U (m, n) in advance.The propagation distance of the diffraction surfaces is dp.It defines sample difference and is layered identity distance
Maximum distance and minimum range from terahertz detector record plane are respectively dmaxAnd dmin, then dpValue be defined as
(3) diffraction surfaces complex amplitude picture breakdown process is propagated in advance.It calculates and extracts pre- propagation diffraction surfaces complex amplitude image U (m, n)
Amplitude and phase image are calculated using the judgement that maximum variance between clusters carry out the maximum variance threshold value T in foreground facets and background face,
Carry out the pre- binaryzation operation for propagating diffraction surfaces complex amplitude image based on obtained threshold value T, obtain binaryzation mask image K (m,
N), it is represented by
Mean value Fuzzy processing in edge is completed to binaryzation mask image K (m, n), obtains the pre- mask image K ' for propagating diffraction surfaces
(m, n) mentions x isolated nonzero value area images in mask image K ' (m, n) by nonzero value region recognition one by one
It takes, and by its zero padding value to the Pixel Dimensions size of former mask image K ' (m, n), obtains x only comprising individually isolated nonzero value
The sub- mask image K ' of image-regioni(i=1,2 ..., x).By obtained x sub- mask image K 'iDiffraction is propagated with pre- respectively
The complex amplitude image U in face is multiplied, and obtains the x pre- sub- complex amplitude image U for propagating diffraction surfacesi(i=1,2 ..., x).
Ui=U × K 'i, i=1,2 ..., x
(4) stage construction complex amplitude image reconstruction synthesis process.The pre- each height for propagating diffraction surfaces is calculated by auto-focusing algorithm
Complex amplitude image UiFocusing propagation distance, and propagated by free-space propagation algorithm, reconstruction obtains each object plane
Complex amplitude image Oi(i=1,2 ..., x).By each object plane complex amplitude image OiRespectively with corresponding sub- mask image
K′iMultiplication obtains image O 'i, calculate each object plane complex amplitude image OiAverage valueAnd with negate operation it is corresponding son
Mask image (1-K 'i) being multiplied obtains image O "i, by image O 'iWith image O "iThe stage construction of additional combining target sample shakes again
Width imaging results 0, the step are represented by
。
2. a kind of THz wave digital hologram imaging method decomposed based on Terahertz diffraction pattern according to claim 1,
It is characterized by: the side output of the avalanche diode Terahertz wave source (1) has THz wave (1a), and avalanche diode is too
The side of hertz wave source (1) towards THz wave (1a) is provided with sample (2), THz wave pyroelectric detector (4) peace
End loaded on THz wave (1a), and detector two-dimension translational platform is fixed with below THz wave pyroelectric detector (4)
(3)。
3. a kind of THz wave digital hologram imaging method decomposed based on Terahertz diffraction pattern according to claim 2,
It is characterized by: the structure of the avalanche diode Terahertz wave source (1), sample (2) and THz wave pyroelectric detector (4)
For the coaxial imaging system of Terahertz.
4. a kind of THz wave digital hologram imaging method decomposed based on Terahertz diffraction pattern according to claim 1,
It is characterized by: the pre- propagation diffraction surfaces complex amplitude picture breakdown process extracts pre- propagation diffraction surfaces for amplitude type sample
Distribution of amplitudes image extract the pre- phase distribution image for propagating diffraction surfaces for phase type sample.
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