Binary modulation screen design method for generating adjustable X-ray super-Rayleigh speckle field
A design method and speckle field technology, applied in optics, instruments, photography, etc., can solve the problems that the statistical characteristics of the light field cannot be reflected, the statistical distribution of the light field is not involved, and cannot be used to realize X-ray correlation imaging, etc. The effect of quality reconstructed images, improved visibility, low signal-to-noise ratio
Active Publication Date: 2020-05-22
SHANGHAI INST OF OPTICS & FINE MECHANICS CHINESE ACAD OF SCI
View PDF6 Cites 0 Cited by
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
[0011] In addition, the optimization goal of the prior art 3 is to realize the mode filter with the mode filtering function, and the optimization goal of the prior art 4 is to improve the quality of the reproduced image, both of which do not involve the statistical distribution of the light field, and the optimized objective function cannot reflect the light field Statistical properties, cannot be used to achieve X-ray correlation imaging
Method used
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View moreImage
Smart Image Click on the blue labels to locate them in the text.
Smart ImageViewing Examples
Examples
Experimental program
Comparison scheme
Effect test
Embodiment Construction
[0042] In order to make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with the specific embodiments of the present invention and the corresponding drawings, but should not limit the protection scope of the present invention.
[0043] like figure 1 As shown, an embodiment of the present invention provides a method for designing a binary modulation screen for generating a controllable X-ray hyper-Rayleigh speckle field, the method comprising the following steps:
[0044] Step 1, choose X-ray with a wavelength of 1nm as the light source, use Au as the material of the modulation screen, the refractive index of Au at 1nm is (1-δ)+iβ, where δ=1.4566×10 -3 , β=5.1455×10 -4 . The modulation screen is divided into 100×100 square cells, and each cell has two states: with holes and without holes; the phase difference of X-rays passing thr...
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More PUM
Login to View More Abstract
The invention discloses a binary modulation screen design method for generating an adjustable X-ray super-Rayleigh speckle field. The method comprises the following steps: setting the target contrastratio of the speckle field; setting cell states of the modulation screen: a porous state and a non-porous state, setting an initial modulation screen and an initial speckle field, and enabling an optimization parameter to be equal to an initial parameter; dividing the optimized modulation screen into a plurality of areas containing a plurality of cells; randomly selecting an area overturning cell;judging whether an overturning condition is met or not, and if so, enabling the optimization parameter to be equal to the overturned parameter; randomly selecting one area from the remaining areas, repeating the above steps, and after all the cells are turned over, obtaining a final optimized modulation screen and a speckle field; judging whether a threshold condition is met or not, and if yes, outputting the modulation screen; and if not, changing the initial modulation screen, and overturning according to the operation. The binary modulation screen generates a contrast-adjustable super-Rayleigh speckle field, is used for X-ray high-order correlated imaging, improves the visibility of a reconstructed image under the condition of a low signal-to-noise ratio, and reduces the requirements for luminous flux.
Description
technical field [0001] The invention relates to the field of X-ray correlation imaging, in particular to a design method of a binary modulation screen for generating an adjustable X-ray super-Rayleigh speckle field. Background technique [0002] When the coherent light is irradiated on the scattering medium, a granular speckle pattern with alternating light and dark will be produced in the transmitted or reflected field. The generation of speckle is formed by the spatial coherence of scattering wavelets of scattering particles. The essence of speckle formation is a wave phenomenon, and various waves of different properties can produce speckle, including X-rays. If the surface fluctuation of the scattering medium is larger than the wavelength of the incident light, the speckle field intensity shows a general statistical characteristic, which is called Rayleigh statistics. At this time, the light intensity of the speckle field obeys the negative e-exponential distribution. F...
Claims
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More Application Information
Patent Timeline
Login to View More IPC IPC(8): G03B42/02
CPCG03B42/02
Inventor 陈倩喻虹陆荣华韩申生
Owner SHANGHAI INST OF OPTICS & FINE MECHANICS CHINESE ACAD OF SCI