Electron microscopy guide


TEM alignment

STEM alignment

Wave interference


Diffractive imaginging


Diffractive imaging via Ptychography

Selected publications by John Rodenburg on the subject of diffractive imaging and related techniques.

When I started working in this subject area, the term 'diffractive imaging' did not exist. My interest has been concerned with solution of the phase problem in the context of a moving source of illumination, as is commonly found in the imaging geometry of the scanning transmission electron microscope. Nowadays, the term diffractive imaging, or coherent diffractive imaging (CDI), has been applied to the 'single-shot diffractive imaging problem': that is, the question of solving for the phase of a single diffraction pattern by using a-priori information about the limited size of the object function. In fact, the moving illumination diffraction problem contains much more phase information, although the best way to extract it was not obvious until recently. This source of information is sometimes called 'ptyographical' information. The word 'ptychography' was coined by Hoppe and Hegerl in the early 1970s, deriving from the Greek word for 'fold'. The principle was originally described as a solution to the crystalline phase problem, but can be extended to continous objects, say via Wigner distribution deconvolution, which I originally developed with the late Richard Bates, or variants (such as the 'half-roe dash' - or Bragg-Brentano sub-set approximation, suitable for weak, kinematical objects). My more recent work has centred on the application of iterative methods to this rich data set.

The great potential advantages of ptychographical imaging in the case of electrons is that it is not so subject to the problem of instabilities and partial coherence as conventional imaging. It does need a good quality lens (difficult to manufacture for atomic-scale wavelengths): the reason that it overcomes the lens-imposed resolution limit in the electron microscope. Furthermore, it gives a direct measure of the phase induced into the wavefield passing through an object: this has many potential application in visible-light microscopy, such as imaging cells with very high contrast.

Ptychography relying on iterative solution methods has recently become quite widely employed in the field of X-ray imaging.

It has recently demonstrated that the resolution of the very best electron lenses can be overcome using electron ptychography . I wrote a short commentary on this, see Nature News and Views

Interested readers new to this area would be advised to start with the articles marked with '*'. I'm afraid I'm not very good at keeping this page up to date.

Humphrey, M.J., Kraus, B., Hurst, A.c., Maiden, A.M., and 
Rodenburg, J.M.
     'Ptychographic electron microscopy using high-angle 
dark-field scattering for sub-nanometre resolution imaging'
     Nature Communications 3, Art. No: 730 

Maiden Andrew M., Humphry Martin J., Zhang Fucai and 
Rodenburg, J.M.
     'Superresolution imaging via ptychography'
     Journal of the Optical Society of America A-Optics
     28 (2011) 604-612  

Maiden, A.M, Rodenburg, J.M.and Humphry, M.J.
     'Optical ptychography: a practical implementation 
	with useful resolution'
     Optics Letters 35 (2010) 2585-2587 

Hue, F., Rodenburg, J.M., Maiden, A.M., Sweeney, F., 
and Midgley,P.A.
     'Wave-front phase retrieval in transmission 
	electron microscopy via ptychography' 
     Physical Review B 82 (2010) 
	Article Number: 121415     

Maiden, A.M., Rodenburg, J.M.
     'An improved ptychographical phase retrieval 
	algorithm for diffractive imaging'
     Ultramicroscopy 109 (2009) 1256-1262 

Liu, C., Walther, T., and Rodenburg, J.M.
     'Influence of thick crystal effects on 
ptychographic image reconstruction with 
     moveable illumination' 
     Ultramicroscopy Volume: 109 (2009) 1263-1275 

Rodenburg, J.M.
      'Ptychography and related diffractive imaging 
	 methods' (REVIEW)*
      Advances in Imaging and Electron Physics, 150 
	(2008) 87-184 

Rodenburg, J.M., Hurst, A.C., Cullis, A.G.,
Dobson,B.R.,Pfeiffer,F., Bunk,O., David,C., 
     Jefimovs, K., Johnson, I.
     'Hard-x-ray lensless imaging of extended 
      Physical Review Letters 98 (2007) Article 
	Number: 034801   

Rodenburg, J.M., Hurst, A.C., and Cullis, A.G.
     'Transmission microscopy without lenses for 
	objects of unlimited size' 
      Ultramicroscopy 107 (2007) 227-231

Faulkner, H.M.L and Rodenburg, J.M.
     ‘Error tolerance of an iterative phase retrieval algorithm
     for moveable illumination microscopy’
     Ultramicroscopy 103 (2005) 153-164 
Rodenburg, J.M. and Faulkner, H.M.L
     ‘A phase retrieval algorithm for shifting illumination’
     Applied Physics Letters 85 (21) 4795-4797
Faulkner, H.M.L. and Rodenburg, J.M
     ‘Moveable aperture lensless transmission microscopy: a novel
     phase retrieval algorithm’
     Physics Review Letters, 93 (2) (2004) 023903/1-4
*Rodenburg , J.M.
     ‘A simple model of holography and some enhanced resolution
	methods in electron microscopy’
     Ultramicroscopy 87 (2001) 105-121 full_paper_PDF
Nellist, P.D. and Rodenburg, J.M.
     'Electron Ptychography I: experimental demonstration beyond
	the conventional resolution limits'
     Acta Cryst A54 (1998) 49-60
Plamann, T. and Rodenburg, J.M.
     'Electron Ptychography II: theory of three-dimensional
	scattering effects’
     Acta Cryst A54 (1998) 61-73
Nellist, P.D., McCallum, B.C. and Rodenburg, J.M.
     'Resolution beyond the 'information limit' in transmission
	electron microscopy'
     Nature, 374 (1995) 630-632
Plamann, T. and Rodenburg, J.M.
     'Double Resolution Imaging with Infinite Depth of Focus in
       single lens scanning microscopy'
     Optik 96 (1994) 31-36
Nellist, P.D. and Rodenburg, J.M.
     'Beyond the conventional information limit: the relevant
       coherence function'
     Ultramicroscopy 54 (1994) 61-74
McCallum, B.C. and Rodenburg, J.M.(P)
     'An error analysis of crystalline ptychography in the STEM
     Ultramicroscopy 52 (1993) 85-99
Rodenburg, J.M., McCallum, B.C. and Nellist, P.D. 
    'Experimental Tests on Double Resolution Coherent Imaging via STEM'
     Ultramicroscopy 48 (1993) 304-314 full_paper_PDF
McCallum, B.C. and Rodenburg, J.M.
     'Simultaneous Reconstruction of Object and Aperture Functions
     from Multiple Far-field Intensity Measurements’
     J Opt Soc Am A 93 (1993) 231-239
McCallum, B.C. and Rodenburg, J.M.
     '2D Optical Demonstration of Wigner Phase-Retrieval
	Microscopy in STEM'
     Ultramicroscopy 45 (1992) 371-380 full_paper_PDF (half-tones 
     very poorly reproduced)
Friedman, S.L. and Rodenburg, J.M.
     'Optical Demonstration of a New Principle of Far-Field
     J Phys D: Appl Phys 25 (1992) 147-154
*Rodenburg, J.M.and Bates, R.H.T.
     'The Theory of Super-Resolution Electron Microscopy via
     Wigner Distribution Deconvolution'
     Phil Trans A 339 (1992) 521-553
Bates, R.H.T and Rodenburg, J.M.
     'Sub-Angstrom Transmission Microscopy: a Fourier Transform
     Algorithm for Microdiffraction Plane Intensity
     Information'Ultramicroscopy 31 (1989) 303-308
*Rodenburg, J.M.
     'The Phase Problem, Microdiffraction and Wavelength-Limited
     Ultramicroscopy 27 (1989) 413-422 full_paper_PDF
Conference papers:

Rodenburg, J.M.
     'Dynamical and geometric effects in ptychographic
	diffractive imaging' 
	CONFERENCE (2007) Volume: 126, 
     art. no. 012035, 2035 (2008) 

Atkinson, K.M., Sweeney, F., and Rodenburg, J.M. 
     'STEM probe characteristics at large defoci 
	for use in ptychographical imaging' - 
     art. no. 012092'
	CONFERENCE (2007) Volume: 126 
     Pages: 12092-12092 

Hurst, A.C. and Rodenburg, J.M. 
     'An optical demonstration of ptychographical 
	imaging for focussed-probe illumination -
     art. no. 012093' EMAG: ELECTRON MICROSCOPY
     Volume: 126 Pages: 12093-12093

 Rodenburg, J.M. 
	‘Can Ronchigrams provide a route to sub-angstrom tomographic
	EMAG Oxford, Inst Phys Conf Conf Ser 179 (2004) 185
Rodenburg, J.M.
	‘Weak lens diffractive imaging’
	Proceedings 13th European Microscopy Congress Antwerp (2004) 379
Faulkner H.M.L. and Rodenburg J.M.
	‘Super-resolution in STEM with moving-probe phase retrieval:
	analysis of success given incorrect initial parameters’
	Proceedings 13th European Microscopy Congress Antwerp (2004) 431
Rodenburg, J.M.
     'Beyond the information limit: a generalisation of imaging
	via diffraction'    EUREM 96 (Dublin) (1996)
Rodenburg, J.M. and Nellist, P.D.
     'Multidetector methods for super-resolution in STEM'
     2nd NIRIM International Symposium on Advanced Materials, Ed
	Bando, Y.,
     Kamo, M. Haneda, H. and Aizawa, T., Tsukuba, Japan (1995) 109
Colman, C P and Rodenburg, J.M.
     'Super-resolution STEM imaging in the presence of specimen
     EMAG 95: IoP Conf Ser No 147 (1995) 107
Plamann, T. and Rodenburg, J.M.
     'Ptychographical imaging of sphalerite structures'
     EMAG 95: IoP Conf Ser No 147 (1995) 117
Rodenburg, J.M.
     'Reducing uncertainties and improving resolution in coherent
	STEM imaging'
     MAS’ 93 meeting, Los Angeles, Microbeam Analysis 2 (1993) 202
Rodenburg. J.M.
     'Below the 1 Å coherent resolution limit: does the future lie
	with STEM'
     Inst Phys Conf Ser No 138 (1993) 235
Nellist, P.D. and Rodenburg, J.M.
     'Image resolution improvement using coherent microdiffraction
	in STEM'
     Inst Phys Conf Ser No 138 (1993) 239
Kirkland, A.I., Rodenburg, J.M., Saxton, W.O., Tsuno, K. and
     Kawasaki, M.
     'Experimental super-resolution via tilt series reconstruction
	in the CTEM'
     Inst Phys Conf Ser No 138 (1993) 247
Plamann, T. and Rodenburg, J.M.
     'Thickness limitations of aberration-free projection imaging'
     Inst Phys Conf Ser No 138 (1993) 243
Rodenburg, J.M.
     'A New Look at the Resolution Problem'
     Micron and Microscopica Acta 23 (1992) 213
Rodenburg, J.M. and McCallum, B.C.
     'A Robust Solution to the Super-Resolution Phase Problem in
     10th Pfefferkorn conference on image processing, Scanning
     Supplement 6 (1992) 223
Friedman, S.L., Rodenburg, J.M. and McCallum, B.C.
     'Phase Reconstruction Imaging in Scanning Transmission
	Microscopy via the Microdiffraction Plane'
     Inst Phys Conf Ser No 119 (1991) 491
Rodenburg, J.M.
     'Higher spatial resolution via signal processing of the
	microdiffraction plane'
     Inst Phys Conf Ser No 98 1 (1989) 103
Nellist, P.D., McCallum, B.C and Rodenburg, J.M.
     'STEM imaging of <110> tetrahedral semiconductors'
     Proc 13th ICEM, Paris (1994) 489
Plamann, T. and Rodenburg, J.M.
     'Simulations on super-resolution imaging of perfect crystals'
     Proc 13th ICEM, Paris (1994) 939
Rodenburg, J.M. and McCallum, B.C.
     'Super-resolution structure determination in STEM'
     Proc 10th Eur Cong on EM (Granada) vol 1 (1992) 125
McCallum, B.C. and Rodenburg, J.M.
     'Blind super-resolution'
     Proc 10th Eur Cong on EM (Granada) vol 1 (1992) 431
Plamann, T. and Rodenburg, J.M.
     'Three-dimensional scattering effects in phase-retrieval
     Proc 10th Eur Cong on EM (Granada) vol 1 (1992) 659

Copyright J M Rodenburg