Accurate wavelength calibration method for compact CCD spectrometer

Sun, Yanchao; Huang, Chan; Xia, Guo; Shen, Jin; Lu, Hongbo

doi:10.1364/josaa.34.000498

Cited by 24 publications

(14 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Wavelength calibration is obtained by exposing the optical system to a calibration light source or sources. Three aspects are critical for obtaining a proper wavelength calibration including (i) the selection of the calibration light, (ii) the determination of the center of characteristic peaks, and (iii) polynomial fitting to the data [ 39 ]. The calibration light source(s) should cover the wavelength range to be calibrated.…”

Section: Data Acquisition and Processingmentioning

confidence: 99%

Technical workflows for hyperspectral plant image assessment and processing on the greenhouse and laboratory scale

Paulus¹,

Mahlein²

2020

GigaScience

View full text Add to dashboard Cite

Background The use of hyperspectral cameras is well established in the field of plant phenotyping, especially as a part of high-throughput routines in greenhouses. Nevertheless, the workflows used differ depending on the applied camera, the plants being imaged, the experience of the users, and the measurement set-up. Results This review describes a general workflow for the assessment and processing of hyperspectral plant data at greenhouse and laboratory scale. Aiming at a detailed description of possible error sources, a comprehensive literature review of possibilities to overcome these errors and influences is provided. The processing of hyperspectral data of plants starting from the hardware sensor calibration, the software processing steps to overcome sensor inaccuracies, and the preparation for machine learning is shown and described in detail. Furthermore, plant traits extracted from spectral hypercubes are categorized to standardize the terms used when describing hyperspectral traits in plant phenotyping. A scientific data perspective is introduced covering information for canopy, single organs, plant development, and also combined traits coming from spectral and 3D measuring devices. Conclusions This publication provides a structured overview on implementing hyperspectral imaging into biological studies at greenhouse and laboratory scale. Workflows have been categorized to define a trait-level scale according to their metrological level and the processing complexity. A general workflow is shown to outline procedures and requirements to provide fully calibrated data of the highest quality. This is essential for differentiation of the smallest changes from hyperspectral reflectance of plants, to track and trace hyperspectral development as an answer to biotic or abiotic stresses.

show abstract

Section: Data Acquisition and Processingmentioning

confidence: 99%

Technical workflows for hyperspectral plant image assessment and processing on the greenhouse and laboratory scale

Paulus¹,

Mahlein²

2020

GigaScience

View full text Add to dashboard Cite

show abstract

“…In the works of other authors, it is shown that CCD-based spectrometers have a number of spectrum distortions, such as nonlinear pixel sensitivity to incident light [ 23 ] and chromatic distortions [ 24 , 25 , 26 ]. In these works, the sources of these errors are considered, as well as the methods of their compensation.…”

Section: Problem Explanationmentioning

confidence: 99%

Algorithm of FBG Spectrum Distortion Correction for Optical Spectra Analyzers with CCD Elements

Anfinogentov

Karimov

Kuznetsov

et al. 2021

Sensors

View full text Add to dashboard Cite

Nonlinear spectrum distortions are caused by the peculiarities of the operation of charge-coupled device elements (CCD), in which the signal exposition time (Time of INTegration–TINT) is one of the significant parameters. A change of TINT on a CCD leads to a nonlinear distortion of the resulting spectrum. A nonlinear distortion of the spectrum, in turn, leads to errors in determining the central wavelength of fiber Bragg gratings (FBGs) and spectrally sensitive sensors, which, in general, negatively affects the accuracy of the measuring systems. This paper proposes an algorithm for correcting the nonlinear distortions of the spectrum obtained on a spectrum analyzer using CCD as a receiver. It is shown that preliminary calibration of the optical spectrum analyzer with subsequent mathematical processing of the signal makes it possible to make corrections in the resulting spectrum, thereby leveling the errors caused by measurements at different TINT.

show abstract

“…It is required to conduct a wavelength calibration when using a CCD spectrometer to determine the corresponding pixel location of each wavelength prior to use [28]. We used a high-end desktop spectrometer (Perkin Elmer Lambda 950) as a secondary standard to determine the wavelength accuracy of our CCD spectrometer.…”

Section: Theorymentioning

confidence: 99%

Improving Optical Measurements: Non-Linearity Compensation of Compact Charge-Coupled Device (CCD) Spectrometers

Nehir

Frank

Aßmann

et al. 2019

Sensors

View full text Add to dashboard Cite

Charge-coupled device (CCD) spectrometers are widely used as detectors in analytical laboratory instruments and as sensors for in situ optical measurements. However, as the applications become more complex, the physical and electronic limits of the CCD spectrometers may restrict their applicability. The errors due to dark currents, temperature variations, and blooming can be readily corrected. However, a correction for uncertainty of integration time and wavelength calibration is typically lacking in most devices, and detector non-linearity may distort the signal by up to 5% for some measurements. Here, we propose a simple correction method to compensate for non-linearity errors in optical measurements where compact CCD spectrometers are used. The results indicate that the error due to the non-linearity of a spectrometer can be reduced from several hundred counts to about 40 counts if the proposed correction function is applied.

show abstract

Accurate wavelength calibration method for compact CCD spectrometer

Cited by 24 publications

References 12 publications

Technical workflows for hyperspectral plant image assessment and processing on the greenhouse and laboratory scale

Technical workflows for hyperspectral plant image assessment and processing on the greenhouse and laboratory scale

Algorithm of FBG Spectrum Distortion Correction for Optical Spectra Analyzers with CCD Elements

Improving Optical Measurements: Non-Linearity Compensation of Compact Charge-Coupled Device (CCD) Spectrometers

Contact Info

Product

Resources

About