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Diffuse Reflectance - Sampling Method Description

Diffuse ReflectanceDiffuse reflectance spectra are acquired using the Labsphere DRA-CA-30I accessory. Diffuse Reflectance UV-Vis Spectroscopy involves numerous light-sample interactions. Spectra may exhibit features associated with the transmission and/or reflection (external and/or internal) of UV-Vis radiation. The Labsphere DRA-CA-30I is a 70 mm diameter diffuse reflectance accessory (DRA) which allows both reflectance and transmittance measurements without removing the accessory from the sample chamber. This accessory can accommodate samples up to 150 mm in diameter. Common applications include measurement of color and sun protection factor (SPF). Powder samples can be analyzed using a cell designed to hold the powder flush against a quartz plate. Monolithic solids can be analyzed provided that a flat surface is available to collect the reflectance spectra and that the sample can fit inside the analysis chamber. An extension that mounts to the front of the analysis chamber is available to extend the depth of the sample as much as six inches.