Structural and optical properties of Dy~(3+):YAlO_3 phosphors for yellow light-emitting diode applications

The spectroscopic properties of a series of Dy~(3+) single-doped and Dy~(3+)/Nd~(3+),Dy~(3+)/Tb~(3+),and Dy~(3+)/Tm~(3+)co-doped YAlO_3(yttrium aluminum perovskite,YAP) phosphors were investigated and compared through the measurements of optical absorption,emission spectra,and fluorescence decay curves.For the Dy~(3+) ion single-doped samples,the intensity of each absorption band increases with an increment in Dy~(3+) ion doping concentration,and the identified strong absorption peak at 447 nm indicates that Dy~(3+):YAP phosphors are suitable to be pumped by a blue laser diode(LD).For all co-doped samples,absorption peaks of Dy~(3+) ion along with some of the absorption bands of Nd~(3+),Tb~(3+),and Tm~(3+) ions are observed.Under 351 and 447 nm excitation,a prominent emission peak at 572 nm was obtained in all the samples,corresponding to Dy~(3+):~4 F_(9/2)→~6 H_(13/2) transition.Here,2 at% Dy~(3+):YAP phosphor exhibits the highest yellow emission intensity under 447 nm pumping.Among the three kinds of Dy~(3+) co-doped phosphors,Dy~(3+)/Tb~(3+):YAP phosphor possesses the dominant yellow emission.The fluorescence decay curves show exponential behaviour and are fitted well.The Commission International de L'Eclairage(CIE)chromaticity coordinates were calculated following the respective emission spectra,and it is found that all the coordinates locate in the yellow region.The energy transfer(ET) processes were investigated and the concentration quenching mechanism was discussed.The obtained results suggest that Dy~(3+)-activated YAP phosphors are good candidates for yellow LED applications.     

White-light emitting single-phase phosphor La3Si6N11:Dy3+,Tb3+: Color tunable emission,thermal stability and energy transfer process

A novel white-light emitting single-phase phosphor La₃Si₆N₁₁:Dy³⁺, exhibiting two emission peaks centering at 475 and 575 nm, was prepared via conventional solid-state reactions. The structure and morphology of La₃Si₆N₁₁:Dy³⁺/Tb³⁺ were investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The emission colors can be tuned from white to yellow-green through increasing the Tb³⁺ concentration in La₃Si₆N₁₁:Dy³⁺,Tb³⁺. The mechanism of energy transfer (ET) from Dy³⁺ to Tb³⁺ is confirmed according to the excitation, emission spectra and decay lifetimes curve. The temperature-dependent luminescence measurements of La_2.83Si₆N₁₁:0.1Dy³⁺,0.07Tb³⁺ were also performed, and a good thermal stability is shown, suggesting superior properties for the application as white light-emitting diodes (w-LEDs) phosphor.     

Influence of dysprosium concentration on sensitivity of luminescent thermometers of phosphors Ca_9Tb(PO_4)_5(SiO_4)F_2

Tb~(3+),Dy~(3+)-co-doped Ca_9 Tb_xDy_(1-x)(PO_4)_5(SiO_4)F_2 phosphors were prepared via high-temperature solidphase reaction method and the potential application in optical temperature measurements due to their color-tunable property was investigated in detail.The photoluminescence emission(PL) and photoluminescence excitation(PLE) spectra results show that the as-prepared phosphors exhibit both Tb~(3+) and Dy~(3+) emissions at 546 nm(~5 D_4-~7 F_5 transition of Tb~(3+)) and 587 nm(~4 F_(9/2)-~6 H_(13/2) transition of Dy~(3+)) upon376 nm excitation,respectively.In addition,the fluorescence decay analysis shows that the lifetime of the Tb3+emission rapidly decreases,which confirms the energy transfer existence between Dy~(3+) and Tb~(3+).Under 376 nm excitation,the temperature dependence of the fluorescence intensity ratios for the dualmission bands peaked at 546 and 587 nm was studied in the temperature range from 303 to 573 K.The results show that with the increase of Dy~(3+) concentration,the relative sensitivity first increases and then decreases,what's more,the maximum relative sensitivity is 3.142×10~(-3)%/K for Ca_9 Tb_xDy_(1-x)(PO_4)_5(SiO_4)-F_2(x=0.4).As a consequence,this preliminary study provides a novel method for exploring the novel thermo meters.     

Comparison of thermoluminescence spectra of MgB407 doped with dysprosium and manganese

A series of magnesium borate phosphors MgB4O7：Dy, MgB4O7：Mn and MgB4O7：Dy,Mn were prepared and their ther-moluminescence （TL） emission spectra were measured. TL emission bands in 480, 575 and 660 nm at 200 and 360 oC were observed in the MgB4O7：Dy due to the transitions of the trivalent rare earth ions Dy3＋. The glow peaks of broad wavelength band around~580 nm at 180 and~290 oC were observed in MgB4O7：Mn due to the emission of Mn2＋ions. The main glow peak of MgB4O7 co-doped with Dy and Mn appeared in 580 nm at~360 oC. When MgB4O7 was co-doped with Dy （0.5 mol.%） and different concentrations of Mn （0.01 mol.%-1.0 mol.%）, the peak in 580 nm at 360 °C was intensified and broadened as the concentration of Mn increased, while the peaks in 480, 680 and 750 nm below 300 °C remained the characteristic emission of Dy3＋and were reduced in intensity. The emission spectra of the MgB4O7：Dy,Mn phosphor showed that the competitive de-excitation processes between Dy3＋and Mn2＋existed and the energy transfer occurred from Dy3＋to Mn2＋. These results meant that rare earth and Mn ions in MgB4O7：Dy,Mn might cause the formation of defects complex that dominated the traps and recombination.     

Effect of BaF2 addition on luminescence properties of Er3+/Yb3+ co-doped phosphate glasses

Er~(3+)/Yb~(3+) co-doped phosphate glasses(P_2O_5-Al_2O_3-BaO-BaF_2-K_2O-Er_2O_3-Yb_2O_3) with varying BaF_2 content,were prepared by a conventional melt quenching technique and their spectroscopic properties were examined through the Raman, absorption, emission and decay measurements. Raman spectra(350-1400 cm~(-1)) of the Er~(3+)/Yb~(3+) co-doped phosphate glasses with varying BaF_2 content, were recorded upon laser excitation at 785 nm. Near infrared luminescence spectra were measured in the1400-1600 nm region under 970 nm diode laser excitation and characteristic band was observed at1533 nm corresponding to ~4Ⅰ_(13/2)→~4Ⅰ_(15/2) transition of Er~(3+) ion. The decay curves for the ~4Ⅰ_(13/2) level of Er~(3+)ion, were measured and the lifetime is found to decrease from 7.94 to 7.70 ms when BaF_2 content increases from 0 to 8 mol% and then increases up to 7.83 ms with further increase in BaF_2 content(12 mol%). The emission cross-section.lifetime and figure of merit for the ~4Ⅰ_(13/2)→~4Ⅰ_(15/2) transition of Er~(3+) ion were evaluated and compared to the other host matrices. The upconversion luminescence was measured and intense red emission was observed for all the studied samples.     

Spectroscopic investigations on Dy3+ ions doped zinc lead alumino borate glasses for photonic device applications

This paper presents the structural, optical absorption, photoluminescence (PL) and decay spectral properties of Dy~(3+)ions doped zinc lead alumino borate (ZPAB) glasses to elucidate their possible usage in photonic devices such as w-LEDs and lasers. A broad hump shown by the XRD spectrum recorded for an un-doped ZPAB glass confirms its non-crystalline nature. The Judd-Ofelt (J-O) intensity parameter evaluated from the measured oscillator strengths of the absorption spectral features were used to estimate various radiative parameters and also to understand the nature of bonding between Dy~(3+)ions and oxygen ligands. Under 350 nm excitation, the as-prepared glasses are exhibiting two emission bands~4F_(9/2)→~6H_(15/2)(blue),and~4F_(9/2)→~6H_(13/2)(yellow) at 483 and 575 nm,respectively. From the PL spectra,the Y/B ratio values, CIE chromaticity color coordinates and color correlated temperature (CCT) were evaluated. The experimental lifetimes measured from the decay profiles are decreasing with increase in Dy~(3+)ions concentration in these glasses which may be attributed to the cross-relaxation and nonradiative multiphonon relaxation process. Decay profiles observed for higher concentration were well fitted to Inokuti-Hirayama (I-H) model to understand the energy transfer process and subsequent decrease in experimental lifetimes. The higher values of radiative parameters, emission cross-sections,quantum efficiency, optical gain and gain band width suggest the suitability of 0.5 mol%of Dy~(3+) ions in these ZPAB glasses for the photonic device application.     

Optical properties and local structure of Dy-doped chalcogenide and chalcohalide glasses

Dy³⁺-doped Ge-Ga-Se chalcogenide glasses and GeSe₂-Ga₂Se₃-CsI chalcohalide glasses were prepared. The absorption, emission properties, and local structure of the glasses were investigated. When excited at 808 nm diode laser, intense 1.32 and 1.55 μm near-infrared luminescence were observed with full width at half maximum (FWHM) of about 90 and 50 nm, respectively. The lifetime of the 1.32 μm emission varied due to changes in the local structure surrounding Dy³⁺ ions. The longest lifetime was over 2.5 ms, and the value was significantly higher than that in other Dy³⁺-doped glasses. Some other spectroscopic parameters were calculated by using Judd-Ofelt theory. Meanwhile, Ge-Ga-Se and GeSe₂-Ga₂Se₃-CsI glasses showed good infrared transmittance. As a result, Dy³⁺-doped Ge-Ga-Se and GeSe₂-Ga₂Se₃-CsI glasses were believed to be useful hosts for 1.3 μm optical fiber amplifier.     

Down- and up-conversion processes in Nd3+/Yb3+ co-doped sodium calcium silicate glasses with concomitant Yb2+ assessment

Novel Nd³⁺/Yb³⁺ co-doped sodium calcium silicate glasses were prepared by melting quenching method:Spectroscopic study was carried out as a function of doping content by fixing sensitizer(Nd³⁺) concentration to 0.2 mol% and adjusting activator(Yb³⁺) from 0 to 1.0 mol%.The energy transfer(ET)mechanisms between Nd³⁺and Yb³⁺ are discussed based on their energy levels and excitation powerdependence emission intensity.Results show that...     

Highly Er3+/Yb3+ Co-Doped Fluoroaluminate Glasses for Microchip Laser at 1.54 μm

A series of highly Er3 /Yb3 co-doped fluoroaluminate glasses were investigated in order to develop a microchip laser at 1.54 μm under 980 nm excitation. Measurements of absorption, emission and up-conversion spectra were performed to examine the effect of concentration quenching on spectroscopic properties. In the glasses with Er3 concentrations below 10% (mol fraction), concentration quenching is low and the Er3 /Yb3 co-doped fluoroaluminate glasses gave stronger fluorescence of 1.54 μm from the 4I13/2→ 4I15/2 transition than those of Er3 singly-doped glasses. In the glass with Er3 concentrations above 10%, concentration quenching of 1.54 μm obviously occurs more than that of the Er3 singly-doped samples because of the back energy-transfer from Er3 to Yb3 . To obtain the highest emission efficiency at 1.54 μm, the optimum in mol fraction when the Er3 concentration is less than 10%.     

Single-phase white-emitting and tunable color phosphor Na3Sc2(PO4)3:Eu2+,Dy3+: Synthesis,luminescence and energy transfer

A series of Eu²⁺/Dy³⁺ single doped and co-doped Na₃Sc₂(PO₄)₃ phosphors were synthesized by the high-temperature solid-state method, and their phase, morphology, and luminescence properties were characterized. Under the excitation of 370 nm, the Na₃Sc₂(PO₄)₃:Eu²⁺,Dy³⁺ phosphor can emit white light whose spectrum is composed of a broad emission band centered at 460 nm and the other three peaks at 483, 577, and 672 nm, respectively. There is energy transfer from Eu²⁺ to Dy³⁺ ion in Na₃Sc₂(PO₄)₃:Eu²⁺,Dy³⁺ phosphor due to the good overlap between the emission spectrum of Na₃Sc₂(PO₄)₃:Eu²⁺ and the excitation spectrum of Na₃Sc₂(PO₄)₃:Dy³⁺, which is further confirmed by the fluorescence lifetime decrease of Eu²⁺ ion with the increase of Dy³⁺ concentration. The process of energy transfer is via dipole–quadruple interaction which is confirmed by applying Dexter's theory. By increasing the Dy³⁺ concentration, the color coordinates of the Na₃Sc₂(PO₄)₃:0.01Eu²⁺,xDy³⁺ phosphors can be adjusted from blue to white, and then to yellow. The optimized concentration of Dy³⁺ ions is 4.0 mol%, beyond which the concentration quenching will take place. The Na₃Sc₂(PO₄)₃:Eu²⁺,Dy³⁺ phosphor shows fairly good resistance to thermal quenching behavior, of which the emission intensity at 423 K can maintain 90.3% of the initial value (298 K). These results suggest that the Na₃Sc₂(PO₄)₃:0.01Eu²⁺,xDy³⁺ phosphors have potential applications as the color-tunable or a single-phase white emitting phosphor in white LEDs.     

Optically stimulated luminescence of Dy~(3+)-doped NaCaPO_4 glass-ceramics

Dy~(3+)-doped glass-ceramics containing NaCaPO_4 crystals were successfully fabricated by heat treatment at base glass,and the luminescence properties were investigated for potential applications in radiation measurements.The photo luminescence(PL) excitation and emission spectra exhibit transitions related to Dy~(3+) ions corresponding to the strongest excitation and emission wavelengths at 351 and 575 nm,respectively.The CW-OSL properties as a function of dopant concentration,pre-heating temperature,pre-heating time and signal fading were investigated.The most appropriate Dy~(3+)ion concentration was found to be 0.25 mol%.The TL glow curves have a broad peak feature peaking at 195±5 ℃.The fading of the OSL signal would keep stable in five days with the intensity value of about 76.11%.The samples also exhibit good signal reusability and a broad linear dose response range(0.02-1000 Gy).     

Design and achieving of multicolor upconversion emission based on rare-earth doped tellurite glasses

yD3＋/Tm3＋ co-doped and yD3＋/Ho3＋/Tm3＋ tri-doped tellurite glasses were synthesized by fusing the mixture of TeO2, PbF2, AIF3, BaF2, Yb2O3, Tm203 and H0203 in a cortmdum crucible at 850 ℃ for 20 min. The synthesized glasses were characterized by upconversion emission spectra under the excitation of 980 nm laser, and the emission colors were investigated according to the CIE-1931 standards. The results indicated that yD3＋/Tm3＋ co-doped tellurite glass exhibited blue upconversion emission with favor- able color coordinates of （0.20, 0.07）. Yb3＋, HO3＋ and Tm3＋ tri-doped tellurite glasses presented white upconversion luminescence under a single 980 nm laser excitation. Moreover, a very wide range of emission colors could be tuned by altering Ho3＋ concentration. Combining the contribution of adjusting Ho3＋ concentration and pump power, near equal energy white light was obtained.     

Glass forming regions and concentration-dependent luminescence properties of Tb~(3+)-activated tellurium-lutetium-tungsten glasses

The glass-forming regions of tellurium-gadolinium-tungsten ternary system prepared at 1000℃for 60 min were firstly determined.To improve density,the full replacement of lutetium for gadolinium to form Tb³⁺-activated tellurium-lutetium-tungsten glasses with the composition of 64 TeO₂-20 WO₃-(16-y)Lu₂O₃-yTb₂O₃were designed for scintillation application.The concentration-dependent optical properties of Tb³⁺-activated tellurium-lutetium-tungsten glasses were fully investigated by transmittance,excitation and emission spectra,together with the luminescence decay curves.The energy transfer mechanism was discussed according to Huang’s rule.The optimized 4 mol%Tb₂O₃activated tellurium-lutetium-tungsten glasses with the density of 6.49 g/cm³and the lifetime of 0.551 ms are developing to be suitable for the potential detection of slow events in the future work.     

Physical,structural and optical studies on magnesium borate glasses doped with dysprosium ion

Intense visible emissions from dysprosium(Dy3+) ions doped glasses became prospective for diverse technological applications. In this paper, physical, optical and structural properties of magnesium borate glasses doped with varied concentrations of Dy_2 O_3 were examined. Such glasses were synthesised by melt quenching method and characterized at room temperature using several analytical techniques.Luminescence and absorption spectra(in the visible region) of as-quenched samples were used to evaluate the physical and optical properties. XRD pattern confims the amorphous state of as-quenched samples. The Fourier transform infrared(FTIR) spectra of glasses reveal various bonding vibrations assigned to different functional groups. UV-vis-NIR spectra disclose eight absorption bands accompanied by a band for hypersensitive transition positioned at 1260 nm(~6 H_(15/2)→~6 F_(11/2)). The values of direct and indirect optical energy band gap of the studied glasses are decreased with the increase of Dy~(3+) ion contents. The photoluminescence spectra of all glasses under the excitation of 380 nm display two prominent emission bands centred at 497 nm(~4 F_(9/2)→~6 H_(15/2), blue) and 587 nm(~4 F_(9/2) →~6 H_(13/2), green).The achieved intense luminescence from the proposed glass composition may be beneficial for solidstate laser applications.     

Tb^3＋ concentration dependent optical properties and energy transfer in GdF3 nanocrystals

By controlling the concentration of Tb3＋, a series of GdF3 samples were synthesized by a hydrothermal method without any surfactant. The samples were characterized by X-ray diffraction （XRD） patterns, field emission scanning electron microscopy （FE-SEM） images, photoluminescence （PL） excitation and emission spectra as well as luminescent dynamic decay curves. The opti-cal properties of Tb3＋, the concentration quenching phenomenon of Tb3＋, and the energy transfer from host Gd3＋to Tb3＋were inves-tigated and discussed based on the concentration of Tb3＋in the GdF3 samples. The experimental results suggested that the optical properties of Tb3＋and the energy transfer from host Gd3＋to Tb3＋could be adjusted by the concentration of Tb3＋in the samples.     

Luminescence properties of Pr3+ and Bi3+ co-doped NaCaTiNbO6 phosphor for red-LEDs

This paper investigates the photoluminescence properties of NaCaTiNbO_6:Pr~(3+) and NaCaTiNbO_6:Pr~(3+),Bi~(3+) phosphors. NaCaTiNbO_6:Pr~(3+) and NaCaTiNbO_6:Pr~(3+),Bi~(3+) powder were synthesized successfully by solid state reaction method. Phase purity was checked using X-ray powder diffractometry(XRD). The excitation and emission spectra were recorded to elucidate the photoluminescence properties of NaCaTiNbO_6:Pr~(3+) and NaCaTiNbO_6:Pr~(3+),Bi~(3+). Furthermore,fluorescence lifetime measurements were performed. The excitation spectra of NaCaTiNbO_6:Pr~(3+) show a main band centered at around 357 nm.The luminescence spectra of NaCaTiNbO_6:Pr~(3+) exhibit a red emission peak at 615 nm from the ~1 D_2→~3 H_4 transition of Pr~(3+) ions. With the introduction of the Bi~(3+) ion into NaCaTiNbO_6:Pr~(3+), the luminescence intensity is enhanced nearly two times. Meanwhile,the absorption band edge of NaCaTiNbO_6:Pr~(3+) is shifted from 380 to 420 nm. Thus, this study shows that the red phosphor NaCaTiNbO_6:Pr~(3+) incorporated with Bi~(3+) is advantageous for light-emitting diode applications.     

Ce3+ sensitized Tb3+ and Dy3+ photoluminescence in β-LaB5O9 prepared by sol–gel method

Rare earth (RE) pentaborates, both α- and β-polymorphs, are good candidates for photoluminescent hosts suitable for various RE activators. Ce³⁺ acts not only as an activator itself, but also as a sensitizer to other rare earth activators, like in the case of commercial green phosphor CeMgAl₁₁O₁₉:Tb³⁺. In this work, two solid solutions of β-La_0.9–xCe_0.1Tb_xB₅O₉ (0 ≤ x ≤ 0.15) and β-La_0.9–yCe_0.1Dy_yB₅O₉ (0 ≤ y ≤ 0.07) were prepared by sol–gel method with high crystallinity, and the phase purity was confirmed with careful analyses on powder X-ray diffraction patterns. Energy transfers are expected due to the overlapping of Ce³⁺ emission with the Tb³⁺/Dy³⁺ excitation. Indeed, the steady photoluminescence spectra indicate the decrease of the Ce³⁺ emission and the increase of the Tb³⁺/Dy³⁺ emission, and the fluorescence decay curves exhibit the decrease of the average lifetime of Ce³⁺. The energy transfer efficiency is estimated to be 60% at x = 0.15 and 55% at y = 0.07, respectively. The mechanism is likely through the dipole–dipole electric interactions for both cases. With this rationale, the Tb³⁺ and Dy³⁺ emissions are greatly enhanced, in particular, the white emission of Dy³⁺ in β-La_0.85Ce_0.1Dy_0.05B₅O₉ is enhanced by 20 times.     

Multi-color luminescence in Eu3+/Tb3+ co-doped ZnAl amorphous materials and their annealed samples

Multi-color luminescence basing on amorphous Eu~(3+)/Tb~(3+) co-doped Zn-Al hydroxides and their annealed samples were studied in detail. Results suggest that excellent red emissions due to Eu~(3+) and green emissions attributed to Tb~(3+) appear under the excitation of favorable wavelength for all the asprepared amorphous samples. Moreover, the emission intensity depends on the Eu~(3+)/Tb~(3+) molar ratio. The samples annealed at 300, 500, and 700 ℃ still exhibit amorphous state,and multi-color luminescence kept in the samples annealed at 300 ℃, while luminescence quenched for the samples annealed at 500 and 700 ℃. However, a broad emission ranging from 450 to 650 nm occurs in some samples annealed at 900 ℃. Further, the fluorescence decay and lifetimes for the as-prepared samples and the samples annealed at 300 ℃ were investigated. It is found that all the decay curves of emissions due to Tb~(3+) and Eu~(3+) present characteristic double exponential function despite their different lifetimes.The present work may be a good example for developing new multi-color even white light emitting materials.     

Energy transfer and luminescent properties of Pr^3＋ and/or Dy^3＋ doped NaYF4 and NaGdF4

The phosphors that are able to convert vacuum ultraviolet（VUV） light into visible light are demanded for the development of novel displaying and lighting devices.NaYF4：Pr3＋,Dy3＋,NaGdF4：Pr3＋,NaGdF4：Dy3＋and NaGdF4：Pr3＋,Dy3＋were prepared by hydrothermal synthesis method and their luminescent properties in VUV-vis spectral region were investigated at room temperature.For NaYF4：Pr3＋,Dy3＋,no energy transfer process from Pr3＋to Dy3＋was observed.However,the introduction of Gd3＋into the fluoride lattice led to intense Dy3＋emissions upon Pr3＋4f5d state excitation.Gd3＋acted as an intermediate,resulting in efficient energy transfer from Pr3＋to Dy3＋in NaGdF4.Pr3＋transferred most of its energy to Gd3＋,and then the energy was transferred from Gd3＋to Dy3＋.So NaGdF4：Pr3＋,Dy3＋not only took full advantage of the intense Pr3＋4f5d absorption,but converted the VUV excitation light into the near-white emission of Dy3＋.     

Spectroscopic investigations on Yb~(3+) doped and Pr~(3+)/Yb~(3+) codoped tellurite glasses for photonic applications

In this work we repo rt on structural and spect roscopic properties of Yb3+doped and Pr~(3+)/Yb~(3+)co-doped TeO_2-Bi_2 O_3-ZnO-Li_2 O-Nb_2 O_5(TBZLN) tellurite glasses.Bending and stretching modes of TeO_2 and Te-OH bond(strong and weak) were analysed from the deconvolution of observed Raman and FT-IR spectra.Based on the absorption measurements,the energy bands of Yb~(3+)and Pr~(3+)ions are assigned.The spectroscopic properties for the radiative transitions of Yb~(3+)and Pr~(3+)ions were reported using McCumber and Judd-Ofelt theories.Visible emission bands originating from ~3 P_1 and ~3 P_0 to lower lying levels of Pr~(3+)were registered under 447 nm excitation.The emission band around 1334 nm assigned to the Pr~3:~1 G_4→~3 H_5 was observed when excited at 980 nm.The stimulated emission cross-section(σ_(emi)(λ))and effective linewidth(Δλ_(eff)) for the ~3 P_1→~3 H_6,~3 P_1→~3 H_5,~3 P_0→~3 H_6,~3 P_0→~3 F_2,~3 P_1→~3 F_3,~3 P_1→~3 F_4,~3 P_0→~3 F_4 and ~1 G_4→~3 H_5 transitions of Pr~(3+)are reported.Upconversion luminescence in Pr~(3+)/Yb~(3+)codoped glass upon 980 nm excitation was measured.Possible resonant transfer processes between Yb~(3+)and Pr~(3+)ions are presented and discussed.The chromaticity co-ordinates were also evaluated from the visible emission spectra showing that Pr~(3+)/Yb~(3+)co-doped glass may be suitable for the development of yellow-orange(λ_(exc)=447 nm) and near white light(λ_(exc)=980 nm) emitting devices in photonics.