POLYCRYSTALLINE PHOSPHOR FILM, PREPARATION METHOD THEREFOR, AND VEHICLE LAMP DEVICE USING SAME

Provided are a polycrystalline phosphor film applicable to a high-power optical device, a preparation method therefor, and a vehicle lamp device using the same, wherein the polycrystalline phosphor film comprises a plurality of phosphor crystals and pores formed between the phosphor crystals, and the phosphor crystal can be a synthesized product comprising at least one rare earth material and cerium (Ce). In addition, the method for preparing a polycrystalline phosphor film can comprise the steps of : preparing a phosphor powder comprising a plurality of phosphor particles; injecting the phosphor powder into a predetermined mold so as to mold the same into a predetermined shape; generating a sintered body by primarily sintering, at a first temperature, the phosphor powder having the predetermined shape; secondarily sintering the sintered body, having been primarily sintered, at a second temperature lower than the first temperature; and forming a polycrystalline phosphor film by processing the sintered body having been secondarily sintered.