Efficient up-conversion emitters are necessary to generate full color 3D display. Rare-earth, co-doped fluorides that convert diode laser light from near infrared to visible red, green, and blue light by sequential two photon absorption are necessary to accomplish this. An up-conversion medium for 3D display, particularly the CSpace® "static volumetric display", can be fabricated by grinding rare-earth-doped fluoride bulk crystals into a powder, and then dispersing the resultant microcrystals within an index matched host. This technique leads to a reduction in display cost, weight, and growing time, as well as provides display scalability. To demonstrate a scalable medium for the CSpace® display, several rare-earth-doped fluoride bulk crystals were ground into a microcrystal powder and then dispersed in different refractive index liquids, including 1.45, 1.456, 1.46, 1.464, 1.468, 1.47, 1.474, 1.476, 1.48, 1.484, and 1.49. Fluorescence strength and transmission measurements were taken. Different particle concentrations were tested and demonstrated, as well. Detailed experiments for these measurements are described in this dissertation. A real volumetric 3D image was constructed inside a prototype display medium of 40 x 40 x10 mm3 using the CSpace® display. A potential future solution is presented, and suggestions to improve the scalable medium are given.