Characterization of Fluoride Phosphors for Diode Pumped Solid-State Lighting Applications

• 作者: Bommareddi Rami Reddy Kristopher Liggins Vernessa M. Edwards
• 来源期刊: 光学与光子学期刊(英文)
• 学科: 化学
• 关键词: Rare-Earth Spectroscopy WHITE-LIGHT Emission COLOR Coordinates Coordinated COLOR Temperature FLUORIDE Materials Laser Induced Fluorescence EUROPIUM TERBIUM DYSPROSIUM Ions
• 年，卷（期）: 2018,（8）
• 页码范围: 288-300
• 页数: 13页
• 分类号: O6

摘要

Phosphor coated diodes are critical to the lighting industry. Rare-earth doped fluoride phosphors are characterized in this work. Spectroscopy and lifetime measurements of CaF2: Dy3+, LaF3: Eu3+ and Tb3+-doped LaF3 and CaF2 crystals were performed by irradiating the samples with 405 and 375 nm diode lasers. Chromaticity diagrams are developed from spectral measurements. Dy3+-doped CaF2 revealed bright white light emission having peaks at 492, 570 and 654 nm. The measured color coordinates are x = 0.322 and y = 0.340 for Dy3+-doped CaF2 and these values are close to those of sunlight and the coordinated color temperature is 6147 K, under 405 m laser excitation. Eu3+-doped LaF3 revealed twenty emission peaks in the visible wavelength region. The color coordinates measured for LaF3: Eu3+ are x = 0.283 and y = 0.293 under 405 nm diode laser excitation and the color temperature is 9557 K. Eu3+-doped LaF3 provides cool white-light, under 405 nm diode laser excitation. Tb3+-doped fluoride crystals revealed bright white light under low power diode laser excitation. The measured color coordinates for Tb3+-doped CaF2 are x = 0.329 and y = 0.558 and the color temperature is 7713 K. The color coordinates for LaF3: Tb3+ are x = 0.342 and y = 0.365 and the coordinated color temperature is 5370 K. These values are close to those of sunlight.