Intensifiers: Detective Quantum Efficiency, Efficiency Contrast Transfer Function and the Signal-to-noise Ratio

1969 ◽  
pp. 577-587
Author(s):  
S. Nudelman
Keyword(s):  
Transfer Function ◽  
Quantum Efficiency ◽  
Signal To Noise Ratio ◽  
Detective Quantum Efficiency ◽  
Signal To Noise ◽  
Contrast Transfer Function ◽  
Noise Ratio

scholarly journals Remarks on T-Grain Technology Applied to Astrophotography

1984 ◽  
Vol 78 ◽  
pp. 141-142
Author(s):  
Alain Maury
Keyword(s):  
Quantum Efficiency ◽  
Signal To Noise Ratio ◽  
Detective Quantum Efficiency ◽  
Signal To Noise ◽  
Noise Ratio

If T-grain Technology can be used to manufacture emulsions of astrcj nomical type, it will provide a better Detective Quantum Efficiency than any existing plate. As Dr. Millikan explains us, this increase in D.Q.E. can result in an increase in Signal to Noise ratio (i.e. increase in coil trast or decrease in granularity) or in an increase of plate speed. As Kodak and we, their customers, don’t have a lot of money to spend for three or more new emulsions, we have now to choose for a new emulsion, which might be a harder one (more contrast), a finer one (better granularity), or a faster one.

Experimental Method to Measure the Detective Quantum Efficiency of a Charge-Coupled Device Camera for Electron Microscopy.

2000 ◽  
Vol 6 (S2) ◽  
pp. 1134-1135
Author(s):  
P. Favia ◽  
S. Cooper ◽  
P. E. Mooney
Keyword(s):  
Quantum Efficiency ◽  
Signal To Noise Ratio ◽  
Ccd Camera ◽  
Detective Quantum Efficiency ◽  
Signal To Noise ◽  
Electron Dose ◽  
Charge Coupled Device ◽  
Noise Ratio ◽  
A Charge ◽  
Image Position

The Detective Quantum Efficiency (DQE) is one of the best parameters to characterize the performance of a charge-coupled device (CCD) camera when electron dose is an issue. This can be when there are beam source brightness limitations as in high-resolution applications or when specimen dose must be limited. For single parameter detectors such as a backscatter detector in a SEM, the DQE is defined as the square of the signal-to noise ratio (SNR) at the output divided by the square of the signal-to-noise ratio at the input:where S, N, and n are respectively the signal, the noise and the electron dose. This definition is not valid to describe the performance of a multi-component device as an imaging detector. In fact a CCD camera is composed of many elements or pixels.

scholarly journals Contrast Transfer Function-Based Exit-Wave Reconstruction and Denoising of Atomic-Resolution Transmission Electron Microscopy Images of Graphene and Cu Single Atom Substitutions by Deep Learning Framework

Nanomaterials ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1977
Author(s):  
Jongyeong Lee ◽  
Yeongdong Lee ◽  
Jaemin Kim ◽  
Zonghoon Lee
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Transfer Function ◽  
Signal To Noise Ratio ◽  
Atomic Resolution ◽  
Single Atom ◽  
Monolayer Graphene ◽  
Signal To Noise ◽  
Contrast Transfer Function ◽  
Transmission Electron

The exit wave is the state of a uniform plane incident electron wave exiting immediately after passing through a specimen and before the atomic-resolution transmission electron microscopy (ARTEM) image is modified by the aberration of the optical system and the incoherence effect of the electron. Although exit-wave reconstruction has been developed to prevent the misinterpretation of ARTEM images, there have been limitations in the use of conventional exit-wave reconstruction in ARTEM studies of the structure and dynamics of two-dimensional materials. In this study, we propose a framework that consists of the convolutional dual-decoder autoencoder to reconstruct the exit wave and denoise ARTEM images. We calculated the contrast transfer function (CTF) for real ARTEM and assigned the output of each decoder to the CTF as the amplitude and phase of the exit wave. We present exit-wave reconstruction experiments with ARTEM images of monolayer graphene and compare the findings with those of a simulated exit wave. Cu single atom substitution in monolayer graphene was, for the first time, directly identified through exit-wave reconstruction experiments. Our exit-wave reconstruction experiments show that the performance of the denoising task is improved when compared to the Wiener filter in terms of the signal-to-noise ratio, peak signal-to-noise ratio, and structural similarity index map metrics.

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