phase retrieval II

Question 1

Talbot Effect

Answer 1

discovered in 1836 a near-field diffraction effect at periodic structures using visible light

Question 2

Transport of Intensity Equation (TIE) disadv

Answer 2

Drawback: Can be difficult to align images exactly, magnification must be considered

Question 3

Signal Retrieval in grating based imaging

Answer 3

via ‘fringe scanning’ or ‘phase stepping’

Question 4

Grating-based phase-contrast imaging provides 3 signals:
1
2
3

Answer 4

attenuation
differential phase
darkfield = scattering

Question 5

grating based imaging uses ….. effect

Answer 5

Talbot Effect

Question 6

Grating-based: to extract the phase information …….. ………needs to be performed

Answer 6

phase stepping

Question 7

multimodal microCT of soft tissue adv

Answer 7

− high contrast for soft tissue
− no need for any tissue treatment (e.g. contrast agents)

accuracy in the lab comparable with synchrotron results
− only resolution slightly worse

Question 8

clinical implementation of phase-contrast and dark-field imaging

Answer 8

− phase contrast: digital mammography
− dark-field: digital mammography (calc) & lung imaging

Question 9

The Talbot effect is a…………. effect.

Answer 9

The Talbot effect is a near-field effect.

Question 10

Self images of the grating are …. in the Talbot distances.

Answer 10

Self images of the grating are repeated in the Talbot distances.

Question 11

What ist the most essential structure of a Talbot interferometer

Answer 11

Phase grating.