qDPC for DigitalMicrograph

Higashimatsuyama, Saitama, Japan (Aug. 15, 2018): HREM Research Inc. introduced qDPC for DigitalMicrograph. The DPC (Differential Phase Contrast) is a technique to obtain a high contrast image from a phase object in STEM (Scanning Transmission Electron Microscope). The qDCP gives a boundary-artifact-free phase contrast image by integrating DPC signals contrary to the solution given by FFT (Fast Fourier transform). The technique used in qDPC [1] has won Microscopy Today Innovation Awards of 2018 [2].

The DPC signal is obtained with a segmented detector as well as a pixelated 4D-STEM detector. The pixelated detector creates more quantitative DPC signals (the first moment of the diffraction intensity) than the segment detector. Thus, the qDPC can give quantitative phase distribution using the DPC signal obtained by the 4D-STEM module (optional). The DPC is ideal for Cs-corrected microscope, since a phase contrast image is obtained with zero objective-lens aberrations that conform to other STEM signals, such as HAADF image.

“The DPC image is difficult to be understood like a DIC (Differential Interference Contrast) image in optical microscopy,” says Dr. Kazuo Ishizuka, Director of HREM Research Inc. “Therefore, the phase contrast image obtained by qDPC will play a major role in studying material as well as biological samples with STEM.”

[1] A Ishizuka, M Oka, T Seki, N Shibata and K Ishizuka: Boundary-artifact-free determination of potential distribution from differential phase contrast signals, Microscopy 66 (2017) 397-405.
[2] Microscopy Today at

About HREM Research Inc.
Founded in 2001, HREM Research Inc. specializes in developing products and services that enhance High-Resolution Electron Microscopy (HREM). Dr. Kazuo Ishizuka, the founder of a company has established the whole technique for HREM image simulation. Thus, the company’s flagship product, Mac/WinHREM, is world leading HREM image simulation software. Currently, HREM Research Inc. is actively working on making useful techniques available to the HREM community. For more information, visit http://www.hremresearch.com or contact support@hremresearch.com.

Kazuo Ishizuka
HREM Research Inc.
14-48 Matsukazedai, Higashimatsuyama
355-0055 JAPAN

Supplementary materials

Two DPC signals (the first moment vector) and the phase contrast image obtained by qDPC. The phase contrast image clearly shows the sample structure, which is difficult to be understood from the DPC signals. Sample is SrTiO3.