CCD Detectors

2008 ◽  
pp. 51-71 ◽  
Author(s):  
L. Strüder ◽  
N. Meidinger
Keyword(s):  
Ccd Detectors

Recent Advances in High Dispersion Spectroscopy of Globular Cluster Stars

1988 ◽  
Vol 132 ◽  
pp. 525-530
Author(s):  
Raffaele G. Gratton
Keyword(s):  
Globular Cluster ◽  
Globular Clusters ◽  
High Dispersion ◽  
Photographic Material ◽  
Recent Advances ◽  
Metal Abundances ◽  
Ccd Detectors ◽  
Major Progress

The use CCD detectors has allowed a major progress in abundance derivations for globular cluster stars in the last years. Abundances deduced from high dispersion spectra now correlates well with other abundance indicators. I discuss some problems concerning the derivation of accurate metal abundances for globular clusters using high dispersion spectra from both the old photographic and the most recent CCD data. The discrepant low abundances found by Cohen (1980), from photographic material for M71 giants, are found to be due to the use of too high microturbulences.

A Simple Algorithm for Despiking Raman Spectra

2018 ◽  
Author(s):  
Darren Whitaker ◽  
Kevin Hayes
Keyword(s):  
Moving Average ◽  
Simple Algorithm ◽  
Mathematical Concepts ◽  
Charge Coupled Device ◽  
Analytical Technique ◽  
Minimal Sample ◽  
Minimal Distortion ◽  
Molecular Specificity ◽  
Ccd Detectors ◽  
Average Filter

Raman Spectroscopy is a widely used analytical technique, favoured when molecular specificity with minimal sample preparation is required.<br>The majority of Raman instruments use charge-coupled device (CCD) detectors, these are susceptible to cosmic rays and as such multiple spurious spikes can occur in the measurement. These spikes are problematic as they may hinder subsequent analysis, particularly if multivariate data analysis is required. In this work we present a new algorithm to remove these spikes from spectra after acquisition. Specifically we use calculation of modified <i>Z</i> scores to locate spikes followed by a simple moving average filter to remove them. The algorithm is very simple and its execution is essentially instantaneous, resulting in spike-free spectra with minimal distortion of actual Raman data. The presented algorithm represents an improvement on existing spike removal methods by utilising simple, easy to understand mathematical concepts, making it ideal for experts and non-experts alike. <br>

A Simple Algorithm for Despiking Raman Spectra

2018 ◽  
Author(s):  
Darren Whitaker ◽  
Kevin Hayes
Keyword(s):  
Moving Average ◽  
Simple Algorithm ◽  
Mathematical Concepts ◽  
Charge Coupled Device ◽  
Analytical Technique ◽  
Minimal Sample ◽  
Minimal Distortion ◽  
Molecular Specificity ◽  
Ccd Detectors ◽  
Average Filter

Raman Spectroscopy is a widely used analytical technique, favoured when molecular specificity with minimal sample preparation is required.<br>The majority of Raman instruments use charge-coupled device (CCD) detectors, these are susceptible to cosmic rays and as such multiple spurious spikes can occur in the measurement. These spikes are problematic as they may hinder subsequent analysis, particularly if multivariate data analysis is required. In this work we present a new algorithm to remove these spikes from spectra after acquisition. Specifically we use calculation of modified <i>Z</i> scores to locate spikes followed by a simple moving average filter to remove them. The algorithm is very simple and its execution is essentially instantaneous, resulting in spike-free spectra with minimal distortion of actual Raman data. The presented algorithm represents an improvement on existing spike removal methods by utilising simple, easy to understand mathematical concepts, making it ideal for experts and non-experts alike. <br>

A Simple Algorithm for Despiking Raman Spectra

2018 ◽  
Author(s):  
Darren Whitaker ◽  
Kevin Hayes
Keyword(s):  
Moving Average ◽  
Simple Algorithm ◽  
Mathematical Concepts ◽  
Charge Coupled Device ◽  
Analytical Technique ◽  
Minimal Sample ◽  
Minimal Distortion ◽  
Molecular Specificity ◽  
Ccd Detectors ◽  
Average Filter

Raman Spectroscopy is a widely used analytical technique, favoured when molecular specificity with minimal sample preparation is required.<br>The majority of Raman instruments use charge-coupled device (CCD) detectors, these are susceptible to cosmic rays and as such multiple spurious spikes can occur in the measurement. These spikes are problematic as they may hinder subsequent analysis, particularly if multivariate data analysis is required. In this work we present a new algorithm to remove these spikes from spectra after acquisition. Specifically we use calculation of modified <i>Z</i> scores to locate spikes followed by a simple moving average filter to remove them. The algorithm is very simple and its execution is essentially instantaneous, resulting in spike-free spectra with minimal distortion of actual Raman data. The presented algorithm represents an improvement on existing spike removal methods by utilising simple, easy to understand mathematical concepts, making it ideal for experts and non-experts alike. <br>

scholarly journals High time-resolution spectroscopic imaging using intensified CCD detectors

2000 ◽  
Vol 319 (2) ◽  
pp. 414-418 ◽  
Author(s):  
J. L. A. Fordham ◽  
H. Kawakami ◽  
R. M. Michel ◽  
R. Much ◽  
J. R. Robinson
Keyword(s):  
Time Resolution ◽  
Spectroscopic Imaging ◽  
High Time ◽  
High Time Resolution ◽  
Ccd Detectors

scholarly journals GEOMETRIC CALIBRATION OF ZIYUAN-3 THREE-LINE CAMERAS COMBINING GROUND CONTROL POINTS AND LINES

2016 ◽  
Vol XLI-B1 ◽  
pp. 163-168
Author(s):  
Jinshan Cao ◽  
Xiuxiao Yuan ◽  
Jianya Gong
Keyword(s):  
Ground Control ◽  
Calibration Model ◽  
Control Points ◽  
Charge Coupled Device ◽  
Geometric Calibration ◽  
Ground Control Points ◽  
The Look ◽  
Ccd Detectors ◽  
True Values ◽  
Better Than

Due to the large biases between the laboratory-calibrated values of the orientation parameters and their in-orbit true values, the initial direct georeferencing accuracy of the Ziyuan-3 (ZY-3) three-line camera (TLC) images can only reach the kilometre level. In this paper, a point-based geometric calibration model of the ZY-3 TLCs is firstly established by using the collinearity constraint, and then a line-based geometric calibration model is established by using the coplanarity constraint. With the help of both the point-based and the line-based models, a feasible in-orbit geometric calibration approach for the ZY-3 TLCs combining ground control points (GCPs) and ground control lines (GCLs) is presented. Experimental results show that like GCPs, GCLs can also provide effective ground control information for the geometric calibration of the ZY-3 TLCs. The calibration accuracy of the look angles of charge-coupled device (CCD) detectors achieved by using the presented approach reached up to about 1.0''. After the geometric calibration, the direct georeferencing accuracy of the ZY-3 TLC images without ground controls was significantly improved from the kilometre level to better than 11 m in planimetry and 9 m in height. A more satisfactory georeferencing accuracy of better than 3.5 m in planimetry and 3.0 m in height was achieved after the block adjustment with four GCPs.

Miniature Spatial Heterodyne Raman Spectrometer with a Cell Phone Camera Detector

2016 ◽  
Vol 71 (5) ◽  
pp. 988-995 ◽  
Author(s):  
Patrick D. Barnett ◽  
S. Michael Angel
Keyword(s):  
Cell Phone ◽  
Diffraction Gratings ◽  
Standard Cell ◽  
High Quality ◽  
Charge Coupled Device ◽  
Raman Spectrometer ◽  
A Cell ◽  
Cooled Ccd ◽  
Ccd Detectors ◽  
Quality Imaging

A spatial heterodyne Raman spectrometer (SHRS) with millimeter-sized optics has been coupled with a standard cell phone camera as a detector for Raman measurements. The SHRS is a dispersive-based interferometer with no moving parts and the design is amenable to miniaturization while maintaining high resolution and large spectral range. In this paper, a SHRS with 2.5 mm diffraction gratings has been developed with 17.5 cm−1 theoretical spectral resolution. The footprint of the SHRS is orders of magnitude smaller than the footprint of charge-coupled device (CCD) detectors typically employed in Raman spectrometers, thus smaller detectors are being explored to shrink the entire spectrometer package. This paper describes the performance of a SHRS with 2.5 mm wide diffraction gratings and a cell phone camera detector, using only the cell phone’s built-in optics to couple the output of the SHRS to the sensor. Raman spectra of a variety of samples measured with the cell phone are compared to measurements made using the same miniature SHRS with high-quality imaging optics and a high-quality, scientific-grade, thermoelectrically cooled CCD.

Sign in / Sign up

Export Citation Format

Share Document