Quantitative determination of modulation transfer function and detection quantum efficiency for standard and anti-reflection YAG scintillator slow-scan CCD-camera

Abstract

Introduction The modulation transfer function (MTF) of a slow-scan CCD camera (Gatan modell 679 attached to our Zeiss EM 912 Omega) has been determined with high precision for the standard and the new anti-reflection YAG scintillator. It is shown that deconvolution of experimental patterns allows the reconstruction of image details down to pixel size. From the analysis of deconvoluted noise patterns we found that for this camera the detection quantum efficiency (DQE) is 0.6 in the typical working range of 300 to 3000 electrons per pixel and does not depend on the scintillator. A full discussion of this work can be found in.Experiment To determine the point spread function (PSF) we punched a hole in a sheet film holder which then was partially covered by one or two knife edges (slit). These masks were projected onto the scintillator. About 600 line scans perpendicular to the edge or slit were extracted and averaged to reduce noise (Fig. 1).

Fully Automated Measurement of the Modulation Transfer Function of Charge-Coupled Devices above the Nyquist Frequency

“…The most common technique to estimate the MTF is the knife edge method (Daberkow et al, 1991; de Ruijter, 1995; Weickenmeier et al, 1995; Meyer & Kirkland, 2000). This requires a straight-edged object, placed directly over the CCD, to be illuminated by a parallel electron beam, thus casting its shadow on the CCD.…”

“…The equivalent in Fourier space is a narrow modulation transfer function~MTF!, attenuating higher frequencies. Precise knowledge of the MTF is imperative for a good correspondence between image simulations and experiments~Boothroyd, 1998; Thust, 2009!. The most common technique to estimate the MTF is the knife edge method~Daberkow et al., 1991;de Ruijter, 1995;Weickenmeier et al, 1995;Meyer & Kirkland, 2000!. This requires a straight-edged object, placed directly over the CCD, to be illuminated by a parallel electron beam, thus casting its shadow on the CCD. In this way Meyer and Kirkland could retrieve the MTF up to 1.6 times the Nyquist frequency n N~M eyer & Kirkland, 2000!.…”

Quantitative High-Resolution Transmission Electron Microscopy of Single Atoms

“…Image detection by the charge-coupled device (CCD) camera dampens pixel-size contrast like a low-pass filter. This behavior is described by the modulation transfer function (MTF), which was measured by the edge method described by Weickenmeier et al (1995) and taken into account by convoluting the image with the MTF. The MTF for the Gatan Ultrascan 1000 CCD camera (Gatan, Inc., Pleasanton, CA, USA) is shown in Figure 1.…”

The quantitative characterization of SiGe layers by analysing rocking profiles in CBED patterns

“…A deconvolution of the experimental images with the point spread function proved to be necessary for a precise quantitative analysis. In this study, we used the point spread function of the CCD camera as has been determined by Weickenmeier et al . (1995 ).…”