Fig. 1From: Investigation of hole-free phase plate performance in transmission electron microscopy under different operation conditions by experiments and simulationsTEM images of the patch on the HFPP film, phase shift evolution, and defocus change with respect to the initial defocus \(\Delta f_{0}\) over time for cases A, B, and C. a–c Case A: small ZOB without HFPP heating. Contamination forms at the center of the ZOB. The phase shift is positive and the defocus is stable (initial value: \(\Delta f_{0} = - 9.96\) µm). d–f Case B: small ZOB with HFPP temperature of 200 °C. No contamination is visible on the HFPP film. A defocused image of the film shows a dark shadow that originates from the irradiation by the ZOB. The phase shift is negative and amounts to about − 0.8π after 2 min. The defocus changes by about 5% (initial value: \(\Delta f_{0} = - 0.62\) µm). Note the different time scale compared to case A. g–i Case C: large ZOB without heating. Contamination forms at the rim of the ZOB. The phase shift is negative and reaches a value of − 3.5π after 2–3 min. The defocus changes by about 18% (initial value: \(\Delta f_{0} = - 1.73\) µm)Back to article page