In situ monitoring of powder blending by non-invasive Raman spectrometry with wide area illumination

► Powder blending monitored non-invasively by wide area Raman spectrometry. ► Effect of particle size on sampling depth and Raman signal investigated for wide area illumination. ► Raman measurements used to monitor mixing dynamics, determine end-point and perform quantitative analysis. ► Higher chemical specificity of Raman compared to near infrared spectrometry offers advantages for multi-component mixtures.