Analysis of the limit to superresolution in incoherent imaging

Treating an imaging system as a linear system and use llinear system properties to d iscuss both coherent and incoherent imaging. Use a one dimensional pin hole camera to study the theory of incoherent imaging. Two different criteria, Rayleigh and Sparrow, are used to define the resolution limits of the camera. From the simple theory define the optical transfer function and the modulation transfer function as appropriate characterizations of complex imaging systems. A review of the human imaging system emphasizes tits idfferences with man made cameras. Coherent imaging is based on Abbe’s theory of microscopy. A simple 4f imaging system can be used to understand how spatial resolution is limited by the optical aperture and by controlling the aperture, we can enhance the edges of an image or remove noise intensity noise on a plane wave. Apodizing the aperture allows astronomers to locate planents orbiting distant stars.

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Analytical and experimental demonstration of depth of field extension for incoherent imaging system with a standard sinusoidal phase mask

Chinese Optics Letters ◽

10.3788/col201210.031101 ◽

2012 ◽

Vol 10 (3) ◽

pp. 031101-31104 ◽

Cited By ~ 1

Author(s):

Hui Zhao Hui Zhao ◽

Yingcai Li Yingcai Li

Keyword(s):

Imaging System ◽

Field Extension ◽

Phase Mask ◽

Depth Of Field ◽

Experimental Demonstration ◽

Incoherent Imaging

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Towards Z-Contrast Imaging in an Aberration-Corrected STEM

Microscopy and Microanalysis ◽

10.1017/s143192760003302x ◽

2000 ◽

Vol 6 (S2) ◽

pp. 106-107

Author(s):

S. J. Pennycook ◽

B. Rafferty ◽

P. D. Nellist

Keyword(s):

Information Transfer ◽

Signal To Noise Ratio ◽

Image Resolution ◽

Contrast Imaging ◽

Atomic Column ◽

Potential Benefits ◽

Potential Factor ◽

Incoherent Imaging ◽

Z Contrast ◽

Contrast Image

The demonstration of an aberration corrector for the STEM promises enormous improvements in the contrast and signal to noise ratio of Z-contrast images, with similar benefits for atomic column EELS. Here we show that the limiting resolution for a zone axis crystal will become not the probe, as in the case of isolated atoms, but the Is Bloch states. In fact, the Z-contrast image becomes a direct image of the Is Bloch states with limiting intensities for large thicknesses roughly proportional to Z The potential benefits for the (STEM) appear to far exceed those for the conventional TEM. Some of these benefits are intrinsic to incoherent imaging: the lack of interference artifacts and the potential factor of two improvement in image resolution were first pointed out by Lord Rayleigh. This improved resolution has been demonstrated by the achievement of sub-ingstrom information transfer in the VG Microscopes HB603U, and the resolution advantage will still apply after aberration correction.

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Polychromatic effects on incoherent imaging through anisoplanatic turbulence

Unconventional and Indirect Imaging, Image Reconstruction, and Wavefront Sensing 2019 ◽

10.1117/12.2528502 ◽

2019 ◽

Author(s):

Ryan Hall ◽

Mark F. Spencer

Keyword(s):

Incoherent Imaging

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Quantification of Compositional Modulations in Self-Assembled Multisheet (Cd, Zn, Mn)Se Quantum Dot Structures

Microscopy and Microanalysis ◽

10.1017/s1431927600027082 ◽

2001 ◽

Vol 7 (S2) ◽

pp. 202-203

Author(s):

T. Topuria ◽

P. Möck ◽

N.D. Browning ◽

L.V. Titova ◽

M. Dobrowolska ◽

...

Keyword(s):

Quantum Dot ◽

Imaging Technique ◽

Optoelectronic Device ◽

Scanning Transmission Electron Microscope ◽

Contrast Imaging ◽

Cdse Qds ◽

Scanning Transmission ◽

Device Applications ◽

Incoherent Imaging ◽

Z Contrast

CdSe/ZnSe based semiconductor quantum dot (Q D) structures are a promising candidate for optoelectronic device applications. However, key to the luminescence properties is the cation distribution and ordering on the atomic level within the CdSe QDs/agglomerates. Here the Z contrast imaging technique in the scanning transmission electron microscope (STEM) is employed to study multisheet (Cd,Zn,Mn)Se QD structures. Since Z-contrast is an incoherent imaging technique, problems associated with strain contrast in conventional TEM are avoided an accurate size and composition determinations can be made.For this work we used a JEOL JEM 201 OF field emission STEM/TEM. The sample was grown by molecular beam epitaxy in order to achieve vertical self-ordering of Cd rich quasi-2D platelet This sample comprises 8 sequences of 10 ML (2.83 nm)Zn0.9Mn0.1Se cladding layer and 0.3 ML (0.09 nm) CdSe sheet, a further 10 ML of Zn0.9Mn0.1Se, and a 50 nm ZnSe capping layer.

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