Examination of cotton maturity and maturity distribution using an infrared focal plane array imaging system

Authors: Santiago Cintron, Michael; von Hoven, Terri; Hinchliffe, Doug; Hron, Rebecca

Submitted to: American Association of Textile Chemists and Colorists Journal of Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/16/2020
Publication Date: 1/1/2021
Citation: Santiago Cintron, M., Von Hoven, T.M., Hinchliffe, D.J., Hron, R.J. 2021. Examination of cotton maturity and maturity distribution using an infrared focal plane array imaging system. American Association of Textile Chemists and Colorists Journal of Research. 8(1):14-24. https://doi.org/10.14504/ajr.8.1.3
DOI: https://doi.org/10.14504/ajr.8.1.3

Interpretive Summary: Cotton maturity is a fiber property related to thickness of the inner cell wall of the fiber. There is interest in new ways to measure this property that do not damage the fiber and that provide a sense of the distribution in a bundle of fibers. The current study seeks to add to the infrared (IR) methods used to determine fiber maturity using an IR imaging system equipped with a spatial array detector. The systems is capable of simultaneously examining cotton fibers bundles at 36 sampling points, thus providing a distribution of measurements for a small sample area (~15 mm). The system can also be utilized to create visual images exploring the spatial distribution of the cotton samples. Previously reported equations were adapted to examine maturity in a variety of cotton standards (4) and a larger set of upland cotton samples (26 additional samples). Maturity distribution plots for the cotton standards resulted in normal distribution plots. A comparison of average maturity values for the set of 30 cottons obtained with a Cottonscope and from IR determinations showed strong linearity and a R2 value of 0.95. A limited comparison with average maturity values obtained using an AFIS instrument were not as strong (R2 = 0.56). Taken together, these results further validate the use of IR measurements for examining cotton fiber maturity and establish the use of the IR system with a array detector for examining and imaging maturity distributions in small cotton fiber bundles.

Technical Abstract: Cotton maturity is a fiber parameter related to thickness of the cotton fiber secondary cell wall. There is a need for developing non-destructive methods for measuring fiber maturity that also provide information on sample distribution. In response, infrared (IR) methods of estimating IR fiber maturity have been previously proposed. The current study seeks to expand IR-based determinations of fiber maturity using an IR imaging system equipped with a Focal-Plane Array (FPA) detector. The systems is capable of simultaneously examining cotton fibers bundles at 36 sampling points, thus providing a distribution of IR measurements for a small sample area (~15 mm, with each sampling point covering a 2.5 x 2.5 mm area). The system can also be utilized to create visual images exploring the spatial distribution of the cotton samples. Reported equations for measuring fiber maturity were adapted to examine maturity in a variety of cotton standards (4) and a larger set of Upland cotton samples (26 additional samples). Maturity distribution plots for the cotton standards resulted in Gaussian distribution plots that provide a sense of the range of maturity values observed in small cotton bundles. A comparison of average maturity values for the set of 30 cottons obtained with a Cottonscope and from FPA IR determinations showed strong linearity and a R2 value of 0.95. A limited comparison with average maturity values obtained using an AFIS instrument were not as strong (R2 = 0.56). Surface contour plots provided a visual representation of the maturity distribution in the cotton bundles. Taken together, these results further validate the use of IR measurement for examining cotton fiber maturity and establish the use of the IR system with a FPA detector for examining and imaging maturity distributions in small cotton fiber bundles.