Background:

2

Conventional neutron radiography is an absorption contrast imaging method which is based on wave character. When neutron wavefront traverses the inspected sample

the variations of the thickness

material and neutron refractive index of the sample bring different phasic difference

which would cause a change in a shape of a neutron wavefront

and the aberrance

wavefront interference behind the sample leads to enhancement of the image sharpness.

Purpose:

2

The aim is to validate thermal neutron to carry out phase contrast imaging.

Methods:

2

Numerical simulation of neutron edge enhancement imaging is processed by MATLAB based on reflection theory and experiment is carried out at a reactor using polychromatic thermal neutron beam line.

Results:

2

The thermal neutron phase contrast imaging can be realized in CMRR (Chinese Mianyang Research Reactor) neutron radiography device when the

L

/

D

is 2 000 and the distance of sample between scintillator is 60 cm.

Conclusion:

2

Both the simulation and experiment results show that a proper

L

/

D

condition would cause image enhancement at the edge of aluminum materials and the monochromatic neutron source is not necessary. The effect is related to

L

/

D

and the distance between sample and scintillator.