Commercial InGaN Research Articles

Efficient CrIII Ion Governed Energy Migration for Broadband Near‐Infrared Emission in Ca3Sc2Ge3O12 Garnet Phosphor

AbstractThe rapid growth in phosphor‐converted near‐infrared light‐emission diodes (NIR‐LEDs) has led to the development of NIR emitter with high efficiency, broadband emission and high thermal stability. In this work, an efficient broad NIR emission of Cr3+ in novel Ca3Sc2Ge3O12 (CSGO) garnet‐based host was developed for the first time, which located at 700 to 1000 nm peaking at 817 nm with a broad bandwidth of ~128 nm. Such a broadband NIR emission originated from the preferential occupancy of Cr3+ in Sc3+ sites with weak octahedral field, which was manifested by the luminescence spectrum and decay behaviors. The Cr3+‐doping concentration was regulated to achieve a good internal quantum efficiency (IQE) of 72.1 % and a fantastic thermal stability (at 423 K, sustained approximately 85 % of the initial intensity). The mechanism for concentration and thermal quenching was further investigated. Benefiting from the excellent luminescence features, a prototype NIR‐LEDs was assembled via integrating the optimized samples with commercial blue InGaN LED chips, which exhibited a satisfactory photoelectric property and a brilliant performance in night vision. These results demonstrated the as‐obtained sample to be a great potential candidate for NIR‐LEDs.

Ultrastable emissive perovskite nanocomposite via dual protection of polymer-grafted TS-1 zeolite for backlight display application

Instability of all-inorganic perovskite quantum dots (PQDs) driven by the inherent ionic nature poses a grand challenge towards their long-term stability in optoelectronic devices. Herein, we report the crafting of a highly stable dual-protected CsPbBr3 perovskite nanocomposite by capitalizing on the encapsulation of a hydrophobic Styrene-Divinylbenzene (St-Dvb) copolymer grafted hierarchical titanium silicalite-1 (TS-1) zeolite shell. Firstly, an optimal hot injection method was used to accommodate CsPbBr3 PQDs into hierarchical TS-1 zeolite. After the modification of terminated Si-OH groups on the surface of TS-1 by phenyltriethoxysilane (PTES), a subsequent polymerization of St and Dvb was implemented using azobisisobutyronitrile (AIBN) as initiator to result in the highly emissive CsPbBr3-TS@St-Dvb nanocomposite, exhibiting outstanding luminescent stability against heat, polar solvents, and UV light irradiation. The as-prepared CsPbBr3-TS@St-Dvb nanocomposite also showed strongly suppressed anion exchange and high compatibility in polymer matrix, enabling improved applicability for versatile lighting and optical display applications. Ultimately, a white light-emitting diode (WLED) composed of green-emitting CsPbBr3-TS@St-Dvb and red-emitting K2SiF6:Mn4+ phosphor onto a commercial blue InGaN LED chip with wide color gamut and excellent stability is demonstrated. This work highlights a judiciously-designed and hard-soft dual-protected strategy to produce ultrastable perovskite nanomaterials with high brightness and durability for backlight display application.

White-light emission from yttrium iron garnet (YIG)

Single-phase phosphors that emit broadband white-light are needed for white-light-emitting diodes (wLEDs) to reach their full potential. However, it is challenging to achieve broad white-light emission from single-phase materials. Consequently, polycrystalline inorganic bulk compounds that emit white-light sans doping are rare. We report on broadband white-light emission from a well-known garnet compound, i.e., yttrium iron garnet (YIG), without activator-ion doping. Upon near-UV excitation at 370 nm, polycrystalline bulk YIG emits broadband white-light with (1931) Commission Internationale de L’Eclairage (CIE) coordinates as (0.28, 0.35) and correlated color temperature (CCT) as 8029 K. Variable excitation wavelengths ranging from 280 to 600 nm enable color-tunable emission as cyan-white-blue-green-yellow-orange-red, including near-white-light emission for a broad range of excitation from 325 to 390 nm. Moreover, a short lifetime (sub-nanosecond) is obtained, which is desirable for LED and other applications. We demonstrated the propriety of YIG as a single-phase converting phosphor for illumination by fabricating prototype wLEDs using commercial InGaN UV-LED chips (λ = 380 nm) for excitation. The CIE coordinates and CCT of prototype wLEDs were obtained as (0.34, 0.37) and 5284 K, respectively. We believe that the reported findings signify the great potential of YIG as a single-phase white-light-emitting phosphor for broadband emission, which offers a new perspective and a viable approach for the development of wLEDs.

Room temperature synthesis of highly stable near-infrared FAPbI3@TEOS perovskite phosphor for NIR light-emitting diodes

In some medical laboratory tests, a sampling method via intravenous injection is required. Previous research pointed out using near-infrared (NIR) light vein detectors to reduce erroneous injections. Therefore, low-cost, high-efficiency and stability NIR phosphors are highly essential. Herein, high-stability, ultrathin SiO2 wrapped NIR-CH(NH2)2PbI3 (FAPbI3) perovskite nanocrystals (NCs) are successfully manufactured via one-step method at room temperature atmospheric synthesis. By optimizing the hydrolytic condensation conditions of tetraethoxysilane (TEOS), the resulting FAPbI3@SiO2 perovskite NCs phosphors exhibits a high photoluminescence quantum yields (PLQYs) of 57.2% and improves water resistance and thermostability. The low-cost NIR light-emitting diodes (NIR-LEDs) fabricated by coating NIR-FAPbI3@SiO2 perovskite NCs phosphors on commercial blue InGaN LEDs chip demonstrated a ∼787 nm EL spectra of NIR-LEDs under the startup voltage of 2.6 V. Even after 12 h of continuous working, no significant changes were observed in the EL spectra of the NIR-LEDs, which indicates that NIR-FAPbI3@SiO2 perovskite NCs phosphor has high capacity in biological applications.

A highly efficient Mn4+ activated Nb-based oxyfluoride red fluorescent material with excellent water stability: preparation and performance analysis.

In this study, an efficient non-rare earth Mn4+-doped K3(NbOF5)(HF2) red fluorescent material was synthesized by using the coprecipitation method. Replacing KF with K2CO3 effectively solved the problem that KF was difficult to stir due to its strong water absorption. The sample was composed of rods. The excitation spectra consisted of two strong excitation peaks at 366 nm and 468 nm. The emission spectra consisted of a series of narrow-band emissions between 580 nm and 680 nm. Besides, the luminescence quantum efficiency (QE) reached 84.3% under the excitation of 468 nm. The fluorescent lifetime of K3(NbOF5)(HF2):Mn4+ was less than 4 ms, which can achieve fast response display in backlight display applications. The WLED was fabricated with K3(NbOF5)(HF2):Mn4+ and commercial YAG:Ce3+ and the commercial InGaN blue chip. At a 30 mA drive current, the WLED device exhibited excellent luminescence properties. The correlated color temperature (CCT) was 3853 K, the Ra was 90.1 and the luminous efficiency was 310.432 lm W-1. Therefore, K3(NbOF5)(HF2):Mn4+ has very broad prospects in WLED lighting and backlight display applications.

Multifunctional behavior of a carbazole derivative: Red phosphorescent emission, aggregation-induced long-life exciton and light-emitting diode application

A D-π-A typed cyanyl-carboxylic derivative (named as CECZA) merely produced prompt fluorescence with lifetime at nanosceond scale in dilute solutions, whose solid-state luminescence exhibited 3.36 μs lifetime with 13.80 % quantum yield (QY, captured at 522 nm for powder at nanometer scale) at 298 K and 43.36 ms lifetime with 30.46 % QY (650 nm, 80 K, tiny crystals). Femtosecond transient absorption, Raman spectroscopy and quantum chemical calculation provided valid clues to reveal its excitonic transition mechanism. The results indicated that the restricted vibration of benzene ring on carbazole group and alkyl chain weakened the vibrational modes of CECZA molecule and strengthened inter-molecular interactions between adjacent molecules at low temperatures, which promoted the persistent phosphorescent emission. Due to strong UV–vis absorption, high quantum efficiency and excellent thermal stability, CECZA can be used as a potential candidate in light-emitting diode (LED) application. Combined with a commercial InGaN blue-emitting chip, CECZA-InGaN emitted daylight white light.

Ultra-Stable and Highly Efficient White Light Emitting Diodes through CsPbBr3 Perovskite Nanocrystals-Silica Composite Phosphor Functionalized with Surface Phenyl Molecules.

Poor stability of CsPbBr3 perovskite nanocrystals (NCs) to moisture/heat/light has significantly limited their application as a green phosphor, despite their outstanding luminescent properties. Here, a remarkably stable CsPbBr3 NCs-silica composite phosphor functionalized with surface phenyl molecules (CsPbBr3 -SiO2 Ph ) is synthesized by controlling low-temperature hydrolysis and condensation reaction of perhydropolysilazane in the presence of CsPbBr3 NCs followed by phenyl-functionalization. Through the process, CsPbBr3 NCs are confined in a compact silica matrix, which is impermeable to H2 O. The synthesis strategy is extended to a classical red quantum dot, CdZnSeS@ZnS NCs, to fabricate a white light emitting diode (WLED) consisting of CsPbBr3 -SiO2 Ph and CdZnSeS@ZnS-SiO2 Ph phosphor and silicone resin packaged on a commercial blue InGaN chip with luminous efficacy (LE) of 9.36 lm W-1 . The WLED undergoes enhancements in both green and red photoluminescence over time to achieve a highly efficient performance of 38.80 lm W-1 . More importantly, the WLED exhibits unprecedented operational stability of LE/LE0 = 94% after 101h-operation at 20mA (2.56V). The ultra-high operational stability and efficient performance are mainly attributed to thermal curing and aging through which grain growth occurs as well as deactivation of defect states by permeated atmospheric O2 .

The Near-infrared luminescence properties and applications of Ca3Lu2Ge3O12:Cr3+ phosphor

The near-infrared (NIR) phosphor-converted LEDs have more merits such as small size, long life and environmental protection to apply in security monitoring, spectrum analysis and biological identification fields. It is necessary to develop high performance NIR luminescent materials matching the commercial blue InGaN chip. This paper reports a broadband emission near-infrared Ca3Lu2Ge3O12:Cr3+ phosphor. Upon 468 nm excitation, the phosphor demonstrates broadband NIR emission centered at ∼793 nm with a large full width at half maximum of ∼130 nm（ΔE=0.258eV). The Cr3+ doped Ca3Lu2Ge3O12 phosphor exhibits good temperature characteristics. The pc-LED device using Ca3Lu2Ge3O12:Cr3+ phosphor excited by a 460 nm commercial blue light chip shows a strong broad NIR emission with output power (38.8 mW at 320 mA). The Cr3+ doped Ca3Lu2Ge3O12 phosphor merged into pc-LED device may be applied in the near-infrared fields.

Change from La2Ti2O7 to LaTiO3 induced by Li2CO3 addition: Higher local symmetry and particle uniformity achieved an efficient Mn4+ activated far red phosphor for agricultural cultivation

In this paper, a synthesized material change from perovskite-layer-structured La2Ti2O7 to perovskite type LaTiO3 induced by Li2CO3 addition was observed. The [TiO6] octahedral site symmetry and particle uniformity showed an obvious variation with the change from La2Ti2O7 to LaTiO3. A broadband far-red emission from 670 to 780 nm emerged when Mn4+, Li+ ions were co-doped. Furthermore, (Mn4+, Li+) co-doped LaTiO3 phosphor can be effectively excited by near-UV and blue lights, which is suitable for combining with commercial InGaN LED chips. The LaTiO3:0.4%Mn4+, 150%Li+ phosphor exhibited a high quantum efficiency of 71.1% and a good thermal stability with emission intensity retained 65% at 423 K. Finally, a LED device was fabricated with the LaTiO3:0.4%Mn4+, 150%Li+ phosphor, which matches well with the absorption of photochrome of PFR and shows a good potential for use in agricultural cultivation fields.

Photoluminescence enhancement of orange-emitting Ca5(PO4)2SiO4:Sm3+ phosphor through charge compensation of A+ (Li+, Na+ and K+) ions for white light-emitting diodes.

The orange-emitting Ca5-x(PO4)2SiO4:xSm3+ (C5PSO:Sm3+) phosphor was prepared via a simple solid-state method, and the charge compensators A+ (A = Li, Na and K) were codoped into C5PSO:Sm3+ for improving the luminescence performance. The influences ofSm3+doping and Sm3+/A+ codoping on the crystal structure and the luminescence performance of the C5PSO:Sm3+ phosphor were investigated in detail. The X-ray diffraction results exhibited that all the as-prepared samples were assigned to the standard structure Ca5(PO4)2SiO4 possessing the P63/m space group. Upon near-ultraviolet excitation at 401 nm, the characteristic emission peaks of the C5PSO:Sm3+ phosphors are located at 558 nm, 605 nm and 656 nm, respectively, which are derived from the 4G5/2 → 6HJ (J = 5/2, 7/2, and 9/2) electron transitions of Sm3+ ions. Furthermore, a significant luminescence improvement of the C5PSO:Sm3+ phosphor was attained through charge compensation of codoped A+ ions, and the emission intensity is enhanced by 1.79-, 1.45-, and 1.14-fold for K+, Na+, and Li+, respectively. In addition, the actual orange-red LED and w-LED fabricated with the as-prepared C5PSO:Sm3+,K+ phosphor showed excellent optical performance. All the results demonstrated that the C5PSO:Sm3+,K+ orange-emitting phosphor could act as a potential orange-red component in the w-LEDs illumination field.

Confining CsPbX3 perovskites in a hierarchically porous MOF as efficient and stable phosphors for white LED

Confining metal-halide perovskites within MOF hosts not only protects them from exterior environment stimulation and isolates them from each other without aggregation, but also enables a variety of new features and applications. In this work, a hierarchically porous MOF host was firstly explored for in-situ confined growth of CsPbX3 perovskite nanocrystallites (PNCs). Compared with the previously used microporous MOF matrixes, this hierarchically porous MOF not only enables the impregnation of perovskite precursors in one step, but also allows more facile diffusion of the reactants, thus giving rise to high loading capacities and uniform distribution of CsPbX3 perovskites. The MOF matrix serves as both template to guide the confined growth of monodispersed CsPbX3 PNCs and encapsulation to enhance the stability of CsPbX3 PNCs. The obtained CsPbX3@MOF nanocomposites show bright luminescence and good resistance to ambient moisture, UV light irradiation, and anion-exchange. By integrating the green-emitting CsPbBr2I@MOF and red-emitting CsPbI3@MOF nanocomposites with a commercial blue InGaN LED chip, we fabricate a primary WLED showing a NTSC value of 125% and Rec. 2020 of 93%, which highlights the potential in backlight display.

Broadband Short-Wave Infrared Light-Emitting Diodes Based on Cr3+-Doped LiScGeO4 Phosphor

Short-wave infrared (SWIR) spectroscopy has recently emerged as an important technology across a wide range of areas, whether industrial, biomedical, or environmental. Nevertheless, it is still a long-standing challenge to develop robust SWIR light sources. The SWIR phosphor-convert light emitting diodes (LEDs) by coating blue LED chips with desirable SWIR-emitting phosphors are becoming an ideal alternative for solid-state SWIR light sources due to its compactness, low-cost, and long operating lifetime, as does the commercial white LEDs. Herein, we report a blue-pumped Cr3+-doped LiScGeO4 SWIR phosphor as a luminescent converter for phosphor-convert SWIR LEDs. This phosphor shows an intense SWIR emission band with a peak wavelength at ∼1120 nm owing to the 4T2 → 4A2 electron transition of Cr3+ when exciting with blue light. The full width at half-maximum (fwhm) of the phosphor is ∼300 nm and the absolute quantum efficiency is determined to be ∼26%. SWIR LED prototypes are constructed by combining the optimized phosphor materials with commercial blue InGaN LED chips, which can generate a commendable emission band in the SWIR region over 800-1600 nm and achieve a maximum output power of ∼4.78 mW at 60 mA with the photoconversion efficiency of 4.4%. The current exploration of Cr3+-doped SWIR-emitting phosphors will lay the foundation to engineer phosphor-convert SWIR LEDs for applications in night-vision surveillance and SWIR spectroscopy technology. These blue-light-excitable SWIR-emitting phosphors can serve as an important complement to the spectral gap of the current Cr3+-doped phosphors in the SWIR region and will pave the way toward cost-effective phosphor-converted solid-state SWIR light sources.

A novel yellow laser candidate: Dy3+ doped Ca3NbGa3Si2O14 crystal

In this article, a series of polycrystalline compounds of DyxCa3-xNbGa3Si2O14 (x = 0.03–0.45) were synthesized to obtain the proper Dy3+ ions doping concentration for the crystal growth. After that, a 5.58 at.% Dy:Ca3NbGa3Si2O14 (Dy:CNGS) single crystal was successfully grown by Czochralski method. Its spectral properties and Judd-Ofelt theory analysis were performed. The crystal has a relatively strong and wide absorption peak at about 453 nm with the absorption cross-section of 1.3 × 10−21 cm2 and a full width at half maximum (FWHM) of 10.2 nm. The Judd-Ofelt parameters Ω2, Ω4 and Ω6 were calculated to be 4.51, 2.93 and 0.19 × 10−20 cm2, respectively. The emission cross-section at 572 nm is 1.8 × 10−21 cm2 with a FWHM of 16.3 nm. The fluorescence time of the 4F9/2→6H13/2 transition is 0.24 ms. The results mean that Dy:CNGS crystal is a potential solid-state yellow laser material suitable for the commercial InGaN laser diode pumping.

Ca8Mg7Si9N22:Ce3+—A Yellow-Emitting Nitride Phosphor for White Light Emitting Diodes

Nitridomagnesosilicate phosphors are promising candidates for white light emitting diodes. Here, we report a yellow nitride phosphor Ca8Mg7Si9N22:Ce3+, which exhibits a broad band emission in the spectral range of 475–675 nm under the excitation of 445 nm. The photoluminescence intensity of Ca8–xMg7Si9N22:xCe3+ (0.01 ≤ x ≤ 0.11) reaches a maximum when x = 0.05. CIE coordinates and the color purity of Ca7.95Mg7Si9N22:0.05Ce3+ are (0.449, 0.531) and 84.0%, respectively. The Ca7.95Mg7Si9N22:0.05Ce3+ phosphor exhibits a good color drifting resistance with a maximum chromaticity shift of 0.0085 at 475 K. By combining the as-synthesized yellow nitride phosphor Ca7.95Mg7Si9N22:0.05Ce3+ and red nitride phosphor SrLiAl3N4:Eu2+ with a commercial blue InGaN chip, an all-nitride white light emitting diode device is fabricated, and a warm white light is generated with chromatic coordinates (0.471, 0.364) and color temperature of 2194 K.

Cryostat setup for measuring spectral and electrical properties of light-emitting diodes at junction temperatures from 81 K to 297 K.

We introduce a cryostat setup for measuring fundamental optical and electrical properties of light-emitting diodes (LEDs). With the setup, the cryostat pressure and the LED properties of the forward voltage, junction temperature, and electroluminescence spectrum are monitored with temperature steps less than 1.5 K, over the junction temperature range of 81-297 K. We applied the setup to commercial yellow AlGaInP and blue InGaN LEDs. At cryogenic temperatures, the fine structure of the electroluminescence spectra became resolved. For the yellow LED, we observed the phonon replica at 2.094 eV that was located 87 meV below the peak energy at the junction temperature of 81 K. For the blue LED, we observed the cascade phonon replicas at 2.599 eV, 2.510 eV, and 2.422 eV with the energy interval of 89 meV. For both LED types, the forward voltage increased sharply toward the lower temperatures due to the increased resistivity of materials in the LED components. We found significant differences between the temperature dependent behaviors of the forward voltages, spectral peak energies, and bandgap energies of LEDs obtained from the Varshni formula. We also noted a sharp pressure peak at 180-185 K arising from the solid-vapor phase transition of water when the base level of the cryostat pressure was approximately 0.4 mPa.

Hardware-Software Complex for the Investigation of the Dynamic Characteristics of Separate Spectral Components of the Emission Spectrum of Leds

We present the description of an automated hardware-software complex intended for measuring the 3 dB frequency of modulation and evaluation of the quantum efficiency of separate spectral components of the full spectrum of electroluminescence of light-emitting diodes, including the range of low levels of excitation. The principle of operation of this complex is based on measuring the spectrum of radiation of a light-emitting diode with the help of an OceanOptics USB2000+ spectrometer in the signal-accumulation mode in the course of transmission of current pulses with given amplitude and repetition frequency through the light-emitting diode with subsequent selection of separate spectral components from the full spectrum of radiation. We present the results of testing the hardware-software complex performed by measuring, as an example, the frequency characteristics of separate spectral components of the full electroluminescence spectrum of commercial InGaN green light-emitting diodes. The analyzed hardware-software complex can be used for the diagnostics of the quality of light-emitting heterostructures with quantum wells.

Non-Rare-Earth Na3AlF6:Cr3+ Phosphors for Far-Red Light-Emitting Diodes.

Emerging phototherapy in a clinic and plant photomorphogenesis call for efficient red/far-red light resources to target and/or actuate the interaction of light and living organisms. Rare-earth-doped phosphors are generally promising candidates for efficient light-emitting diodes but still bear lower quantum yield for the far-red components, potential supply risks, and high-cost issues. Thus, the design and preparation of efficient non-rare-earth activated phosphors becomes extremely important and arouses great interest. Fabrication of Cr3+-doped Na3AlF6 phosphors significantly promotes the potential applications by efficiently converting blue excitation light of a commercial InGaN chip to far-red broadband emission in the 640–850 nm region. The action response of phototherapy (∼667–683 nm; ∼750–772 nm) and that of photomorphogenesis (∼700–760 nm) are well overlapped. Based on the temperature-dependent steady luminescence and time-resolved spectroscopies, energy transfer models are rationally established by means of the configurational coordinate diagram of Cr3+ ions. An optimal sample of Na3AlF6:60% Cr3+ phosphor generates a notable QY of 75 ± 5%. Additionally, an InGaN LED device encapsulated by using Na3AlF6:60% Cr3+ phosphor was fabricated. The current exploration will pave a promising way to engineer non-rare-earth activated optoelectronic devices for all kinds of photobiological applications.

YAGG:Ce transparent ceramics with high luminous efficiency for solid-state lighting application

A series of Y2.985Al5–xGaxO12:0.015Ce (YAGG:Ce, x = 0, 1, 2, 3, 4, 5) transparent ceramics were prepared via a solid-state reaction method. Two-step sintering technique was proved to be an effective approach to prepare functional ceramics with high Ga concentration, and Y3Ga5O12 (YGG) transparent ceramic was successfully prepared for the first time. According to the variation of Al/Ga ratio, regulation of band structure and luminescence properties of YAGG:Ce transparent ceramics were effectively investigated. When Ga substitutes Al sites, the tetrahedral site is more favorable compared to the octahedral site for Ga to occupy according to the first-principle calculation. A continuous blue shift of the emission from 565 to 515 nm was achieved as Ga was gradually introduced into Y3Al5O12:Ce matrix. High quality green light was obtained by coupling the YAGG:Ce ceramics with commercial blue InGaN chips. Transparent luminescence ceramics accomplished in this work can be quite prospective for high power LED application.

CsPb(Br,I)3 embedded glass: Fabrication, tunable luminescence, improved stability and wide-color gamut LCD application

All-inorganic cesium lead halide perovskites with high quantum efficiency and narrow emission bandwidth has emerged as a new-generation color converter for wide-color-gamut LCD. Herein, we present the fabrication of this kind of material in a green, time-saving, low cost, and batched way, following the phase transformation from amorphous to crystalline via glass self-crystallization or thermally-/mechanically-driven glass crystallization. A close insight was put into the microstructure-property relationship by making comparison on the samples via different crystallization routes. The CsPbBr3 in glass yields quantum efficiency of ~48% and emission bandwidth of ~30 nm. The color-tunable emission is facilely realized with the introduction of I− species, based on a solid-solution approach. It was demonstrated that the tough issue of poor thermal-/photo-/moisture-stability in perovskites can be well addressed, thanking to the encapsulation of water- and oxygen-impermeable glass matrix. Moreover, a prototype w-LED was fabricated by coupling the CsPbBr3 devitrified glass, the K2SiF6:Mn4+ phosphor-in-glass, with the commercial InGaN blue chip, producing an ultra-wide color gamut of 103.1% NTSC after passing through the commercial RGB color filters.

Preparation and characterizations of Pr3+:CaF2 transparent ceramics with different doping concentrations

0.2–5.0 at% Pr3+-doped CaF2 transparent ceramics were fabricated by hot-pressed processing for the first time. The phase compositions, microstructure and optical characteristics of the presented transparent ceramics were examined systematically. The average in-line transmittance of Pr:CaF2 transparent ceramics (2.0 mm thick) with high Pr3+ doping concentrations (1.0–5.0 at%) exceeds 86% at the wavelength of 1200 nm. The absorption spectrum manifests that the prepared Pr:CaF2 transparent ceramics contain some absorption peaks overlapped with emission bands of the commercial InGaN laser diodes. Further, a detailed investigation on the visible emission properties as a function of Pr3+ concentrations in CaF2 transparent ceramics was reported. The emission spectra presented two main characteristic peaks at 496 nm (bluish green) and 656 nm (red) corresponded to the transitions of 3P0→3H4 and 3P0→3F2 for Pr3+ activator ions. With the increase of the Pr3+ doping concentrations, the emission intensity and decay lifetimes decreased generally attributed to the concentration quenching effect. Details on energy transfer mechanism of Pr3+ in CaF2 transparent ceramics were demonstrated and discussed.