Phosphor coated diodes are critical to the lighting industry. Rare-earth doped\nfluoride phosphors are characterized in this work. Spectroscopy and lifetime\nmeasurements of CaF2: Dy3+, LaF3: Eu3+ and Tb3+-doped LaF3 and CaF2 crystals\nwere performed by irradiating the samples with 405 and 375 nm diode\nlasers. Chromaticity diagrams are developed from spectral measurements.\nDy3+-doped CaF2 revealed bright white light emission having peaks at 492,\n570 and 654 nm. The measured color coordinates are x = 0.322 and y = 0.340\nfor Dy3+-doped CaF2 and these values are close to those of sunlight and the\ncoordinated color temperature is 6147 K, under 405 m laser excitation.\nEu3+-doped LaF3 revealed twenty emission peaks in the visible wavelength region.\nThe color coordinates measured for LaF3: Eu3+ are x = 0.283 and y =\n0.293 under 405 nm diode laser excitation and the color temperature is 9557\nK. Eu3+-doped LaF3 provides cool white-light, under 405 nm diode laser excitation.\nTb3+-doped fluoride crystals revealed bright white light under low\npower diode laser excitation. The measured color coordinates for Tb3+-doped\nCaF2 are x = 0.329 and y = 0.558 and the color temperature is 7713 K. The\ncolor coordinates for LaF3: Tb3+ are x = 0.342 and y = 0.365 and the coordinated\ncolor temperature is 5370 K. These values are close to those of sunlight.
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