READ ME File For 'Compact nano-void spectrometer based on a stable engineered scattering system - dataset'
Dataset DOI: 10.5258/SOTON/D2314
Date that the file was created: July, 2022
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GENERAL INFORMATION
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ReadMe Author: PRZEMYSLAW FALAK, University of Southampton [ORCID: 0000-0002-2970-0700]
Date of data collection: JULY 2021- JULY 2022
Information about geographic location of data collection: Southampton, UK
Related projects:
EPSRC 'Compact Tailored Spectrometer'
EPSRC 'National Hub in High Value Photonic Manufacturing' (EP/N00762X/1)
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SHARING/ACCESS INFORMATION
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Licenses/restrictions placed on the data, or limitations of reuse: No restrictions. Can be used based on CC-BY.
This dataset supports the publication:
AUTHORS: QI SUN, PRZEMYSLAW FALAK, TOM VETTENBURG, TIMOTHY LEE, DAVID B. PHILLIPS, GILBERTO BRAMBILLA, MARTYNAS BERESNA
TITLE: Compact nano-void spectrometer based on a stable engineered scatterer
JOURNAL: Photonics Research
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DATA & FILE OVERVIEW
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This dataset contains one archived file .zip with the following content:
1) This README.txt file,
2) Subfolder "Stability"
3) Subfolder "Spectrometer"
This dataset consists of 2 sub-folders titled "Stability" and "Spectrometer" and 11 .fig files in total.
The "Stability" folder contains the following 6 sub-files:
a) "21_11_15_7_days_single_wavelength_stability_RMS.fig" - this file contains RMS (root mean square) of the difference between first and all subsequent captured speckles during 7 days (168 hours) measurement (captured every 10 minutes).
This file contains five plotted lines - which reffer to unmodified data, binned data (order 5 and 20) and cropped data (order 5 and 20).
b) "21_11_15_7_days_single_wavelength_x_y_displacement.fig" - this file contains transformation matrix x and y (translational) displacements between the reference (first) and any subsequent speckles for unmodified dataset. For clarity, data was captured every 100 minutes for 7 days period.
NOTE: for files (a) and (b) there are regions where either RMS (a) or displacement (b) suddenly peaks to the unreasonably high values. It is due to laser source turning off periods. These segments shall be ignored during data interpretation.
c) "21_11_15_Chip_X_Y_displacements_24h.fig" - transformation matrix translational displacements but with data captured every 10 minutes and for the first 24 hours of the experiment.
d) "21_11_15_Chip_stability_7_days.fig" - this figure shows stability of the chip-based device, for 168 hours. It consists of two line plots on the same figure: the reference and reconstructed wavelegnths.
e) "22_07_19_MMF_50cm_stability_12_hours.fig" - analogus stability measurement, but for 50 cm jacketed straight MMF fibre (FG105LCA, Thorlabs) - the measurements lasted for 12 hours, since the demonstrated instability of such system was evident after that time.
f) "22_02_25_Chip_stability_7_days_modulation.fig" - stability measurement of chip-based spectrometer, but the wavelength was changed in equal time-periods (steps-like modulation) in range 1042.5-1062.5 nm with the central wavelength of 1052.5 nm. Total measurement time: 180 hours.
The "Spectrometer" folder contains the following 5 sub-files:
a) "21_08_10_Binning_vs_cropping_summary_results.fig" - this file contains 6 sub-plots. It shows an effect of cropping (order 5 and 20) and binning (order 5 and 20) on the spectral correlation matrix. The unmodified correlation matrix and reconstruction errors are plotted as well.
b) "21_11_09_Binned_spectrum.fig" - this file demonstrates an effect of binning (order 5 and 20) on sinusoidally-modulated spectrum shape.
c) "21_11_09_Cropped_spectrum.fig" - this file contains information on an analogous effect of the cropping on the sinusoidally-modulated spectrum shape.
d) "21_11_09_Ref_ideal_reality.fig" - this file contains information on the spectral reconstruction, sowing the "reference pattern" (perfectly sinusoidally-modulated wave), "ideal" case - when laser wavelength is the same (no laser tunability problem) and "real" case - when during measurement laser motor step cannot replicate exactly the same wavelength.
e) "21_11_09_Twin_peaks_spectrum_resolution.fig" - this file contains synthesised twin-peaked spectrum which demonstrates 0.1 nm spectral reconstructive resolution of the scattering chip-based spectrometer.
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METHODOLOGICAL INFORMATION
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Description of methods used for collection/generation of data: The raw data was collected as speckle patterns captured by IR camera (.png files) and further processed by MATLAB scripts.
Methods for processing the data: Generated data was processed by computational MATLAB scripts and saved as MATLAB figure files (.fig).
Software- or Instrument-specific information needed to interpret the data, including software and hardware version numbers: All files within this dataset are MATLAB(C) MathWorks Inc. figure files (.fig).
All files were created in MATLAB R2021a and shall be opened by any MATLAB version, starting from R2014b.
The .fig files contain the data which can be accessed by using MATLAB commands.
Environmental/experimental conditions: temperature: 22.7 - 23.82C, humidity: 39.5-41%.
People involved with sample collection, processing, analysis and/or submission: PRZEMYSLAW FALAK and QI SUN
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DATA-SPECIFIC INFORMATION
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Filename: 21_11_15_7_days_single_wavelength_stability_RMS.fig
Number of variables: 2
Number of cases: 5
Variable list, defining any abbreviations, units of measure, codes or symbols used:
- time (hours),
- root mean square (RMS), dimensionless.
Cases:
- unmodified data,
- cropping applied, order of 5,
- cropping applied, order of 20,
- binning applied, order of 5,
- binning applied, order of 20.
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DATA-SPECIFIC INFORMATION
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Filename: 21_11_15_7_days_single_wavelength_x_y_displacement.fig
Number of variables: 2
Number of cases: 1
Variable list, defining any abbreviations, units of measure, codes or symbols used:
- time (hours),
- approximations of the translational components of the transformation matrix (pixels),
Cases:
- transformation matrix approximation translational x and y coordinate.
Specialized formats or other abbreviations used:
This dataset has samples taken every 100 minutes for 168 hours.
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DATA-SPECIFIC INFORMATION
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Filename: 21_11_15_Chip_X_Y_displacements_24h.fig
Number of variables: 2
Number of cases: 1
Variable list, defining any abbreviations, units of measure, codes or symbols used:
As above, the x and y approximations of the translational components of transformation matrix
Specialized formats or other abbreviations used:
This dataset has samples taken every 10 minutes for 24 hours period.
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DATA-SPECIFIC INFORMATION
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Filename: 21_11_15_Chip_stability_7_days.fig
Number of variables: 2
Number of cases: 2
Variable list, defining any abbreviations, units of measure, codes or symbols used:
- time (hours),
- wavelength change (delta lambda) in nm
Cases:
- reference (Yokogawa AQ6370D) measurements of wavelength,
- reconstructed wavelength by investiagted chip-based device.
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DATA-SPECIFIC INFORMATION
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Filename: 22_07_19_MMF_50cm_stability_12_hours.fig
Number of variables: 2
Number of cases: 2
Variable list, defining any abbreviations, units of measure, codes or symbols used:
- time (hours),
- wavelength change (delta lambda) in nm
Cases:
- reference (Yokogawa AQ6370D) measurements of wavelength,
- reconstructed wavelength by 50cm MMF (multi moded fibre FG105LCA, Thorlabs) based device.
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DATA-SPECIFIC INFORMATION
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Filename: 22_02_25_Chip_stability_7_days_modulation.fig
Number of variables: 2
Number of cases: 2
Variable list, defining any abbreviations, units of measure, codes or symbols used:
- time (hours),
- wavelength in nm
Cases:
- reference (Yokogawa AQ6370D) measurements of wavelength,
- reconstructed wavelength by investiagted chip-based device.
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DATA-SPECIFIC INFORMATION
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Filename: 21_08_10_Binning_vs_cropping_summary_results.fig
Number of variables: 4
Number of cases: 3
Variable list, defining any abbreviations, units of measure, codes or symbols used:
- wavelength (nm) (lambda),
- correlation coeficient (dimensionless) from -0.02-0.12
- order of binning/cropping (integer)
- reconstruction standard error (nm)
Cases:
- unmodified data,
- data with applied pixel binning (order of 5),
- data with further pixel binning (order of 20).
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DATA-SPECIFIC INFORMATION
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Filename: 21_11_09_Binned_spectrum.fig
Number of variables: 2
Number of cases: 3
Variable list, defining any abbreviations, units of measure, codes or symbols used:
- wavelegnth (nm) (lambda),
- relative intensity (0-1), dimensionless
Cases:
- unmodified data,
- data with applied pixel binning (order of 5),
- data with further pixel binning (order of 20).
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DATA-SPECIFIC INFORMATION
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Filename: 21_11_09_Cropped_spectrum.fig
Number of variables: 2
Number of cases: 3
Variable list, defining any abbreviations, units of measure, codes or symbols used:
- wavelegnth (nm) (lambda),
- relative intensity (0-1), dimensionless
Cases:
- unmodified data,
- data with applied pixel cropping (order of 5),
- data with further pixel cropping (order of 20).
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DATA-SPECIFIC INFORMATION
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Filename: 21_11_09_Ref_ideal_reality.fig
Number of variables: 2
Number of cases: 3
Variable list, defining any abbreviations, units of measure, codes or symbols used:
- wavelegnth (nm) (lambda),
- relative intensity (0-1), dimensionless
Cases:
- reference line (ideal, sinusoidally-modualted wavelength spectrum),
- "ideal" case (no laser tuning wavelength mismathing (limitation due to motor step)) spectrum reconstruction,
- "real" case of spectrum reconstruction (laser tuning mismatches wavelengths due to motor step limitation).
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DATA-SPECIFIC INFORMATION
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Filename: 21_11_09_Twin_peaks_spectrum_resolution.fig
Number of variables: 2
Number of cases: 1
Variable list, defining any abbreviations, units of measure, codes or symbols used:
- wavelegnth (nm) (lambda),
- relative intensity (0-1), dimensionless
Cases:
- synthesised twin-peaks speckle-based spectrum, showing the best achievable spectral resolution of two peaks, separated by 0.1nm.