Samples Certification in Colorimetry for CIELAB Color Space

• Autor(a) principal: Brasil, Francisco Maria Baltazar Alçada Xara
• Data de Publicação: 2021
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10362/147474
• topic: Colorimetry; Spectrophotometry; CIELAB; Reflectance; Transmittance; RAL; Domínio/Área Científica::Engenharia e Tecnologia::Engenharia Mecânica

The present study was developed in the Metrology Department (DMET) of the Portuguese Institute for Quality (IPQ). The objective was to participate to the development of a field of colorimetry based on spectrophotometry. Indeed, spectrophotometry ensures high accuracy measurement results, which can be very beneficial for studies in colorimetry, allowing a better quality in the processes of the colors linearization. As colorimetry only deals with the visible region of the electromagnetic spectrum, it is required to befall the spectrophotometry measurements along all that region of the spectrum. Then using the reflectance or the transmittance measured by the spectrophotometer, the data collected can be used to determine the chromaticity coordinates of a sample in diverse color spaces. In this work, the CIELAB color space was chosen to be explored due to being a uniform color space, facilitating comparisons between different colors, due to equal distances in this color space, representing equal perceived color differences and to establish a correspondence with the RAL system, which is an European color matching system, developed by the RAL German Institute for Quality Assurance and Labeling.