Figure 4

Mean of the CIE x values for two perpendicular directions (line-by-line and column-by-column averaging) of the data matrix as a function of the pixel number. Left side (a-c): Differences of diffuse and specular reflectivity for a globe-top size of 3 mm (CIE x value of about 0.3300). Middle (d-f): Differences for globe-top sizes of 1 mm and 3 mm for diffuse reflectivity (CIE x value of about 0.3300). Right side (g-i): Differences of diffuse and specular reflectivity for a globe-top size of 3 mm and the phosphor concentration adjusted in order to achieve a CIE x value of about 0.3800 for a diffuse reflectivity of 85%. Top: reflectivity 85%, middle: 70%, bottom: 100%.