Phosphor Layer Research Articles

Review of Low-Frequency Noise Properties of High-Power White LEDs during Long-Term Aging.

Low-frequency noise investigation is a highly sensitive and very informative method for characterization of white nitride-based light-emitting diodes (LEDs) as well as for the evaluation of their degradation. We present a review of quality and reliability investigations of high-power (1 W and 3 W) white light-emitting diodes during long-term aging at the maximum permissible forward current at room temperature. The research was centered on the investigation of blue InGaN and AlInGaN quantum wells (QWs) LEDs covered by a YAG:Ce3+ phosphor layer for white light emission. The current-voltage, light output power, and low-frequency noise characteristics were measured. A broadband silicon photodetector and two-color (blue and red) selective silicon photodetectors were used for the LED output power detection, which makes it possible to separate physical processes related to the initial blue light radiation and the phosphor luminescence. Particular attention was paid to the measurement and interpretation of the simultaneous cross-correlation coefficient between electrical and optical fluctuations. The presented method enables to determine which part of fluctuations originates in the quantum well layer of the LED. The technique using the two-color selective photodetector enables investigation of changes in the noise properties of the main blue light source and the phosphor layer during the long-term aging.

Triple-layer remote phosphor structure: A potential packaging configuration to enhance both color quality and lumen efficiency of 6,000–8,500 K WLEDs

Abstract To achieve further enhancement in the lighting quality of white light-emitting diodes (WLEDs), this study proposed a packaging structure with three different phosphor layers, called triple-layer remote phosphor structure. This structure can provide an overall control over the light color distribution of WLEDs. The yellow-green-emitting CaAl2O4:Mn2+ phosphor and red-emitting CaMoO4:Eu3+ phosphor are used along with the original yellow-emitting YAG:Ce3+ phosphor to fabricate the triple-layer structure. The concentration of yellow-emitting YAG:Ce3+ phosphor is required to be decreased as the concentrations of other phosphors increase to keep the predetermined correlated color temperatures. The color rendering index (CRI) and the color quality scale (CQS) are measured to reach a thorough color quality assessment for WLEDs. The color management can be achieved by adjusting the concentration of red-emitting CaMoO4:Eu3+ phosphor to enhance the red emission. In addition, adjustment of the concentration of yellow-green-emitting CaAl2O4:Mn2+ phosphor can result in higher luminous efficiency owing to its control over the green light components. Higher CRI is observed when CaMoO4:Eu3+ concentration increases, while an increase in CaAl2O4:Mn2+ phosphor leads to much lower CRI. The CQS – on the other hand – is remarkably high when the CaMoO4:Eu3+ concentration range is about 10wt%–14wt%, regardless of the proportion of the CaAl2O4:Mn2+ phosphor. Furthermore, 40% enhancement in luminous efficiency is also achieved since light scattering is minimized by the boosted green-light emission spectra. Manufacturers can take these findings as reference to fabricate high-quality WLED lights that fulfill all their requirements.

Luminescent core–shell Ca2MoO5:Eu3+-MCM-41 structure for sustained drug release

The spherical mesoporous MCM-41 coated with a novel Ca2MoO5:Eu3+ phosphor layer was prepared for the first time. The obtained Ca2MoO5:Eu3+-MCM-41 was characterized via XRD and FT-IR. The crystal system of the Ca2MoO5 phase was determined to be orthorhombic, and its space group was found to be Ima2 (46), and its cell parameters were a = 16.175, b = 5.1514, c = 5.6977 A°; α = β = γ = 90°. The particle dimensions of MCM-41 and Ca2MoO5:Eu3+-MCM-41 nanoparticles were determined to be 260 nm and 229 nm via scanning electron microscopy analysis. Bortezomib was loaded into the Ca2MoO5:Eu3+-MCM-41 nanoparticles under scCO2 at 200 bars and 40 °C. The results of the TG analysis showed that the amount of drug-loaded to MCM-41 and Ca2MoO5:Eu3+-MCM-41 nanoparticles were determined to be 14.02% and 3.02%, respectively. The BET analysis showed that while the specific surface area and pore volume of MCM-41 and Ca2MoO5:Eu3+ before Bortezomib (BTZ) loading were 1,506 m2/g and 267 m2/g, respectively, after drug loading these values were found to decrease to 488 m2/g and 7.883 m2/g. It was determined that BTZ was released from the nanoparticles in a sustained manner over 66 h. The R2 value, which was calculated to be 0.9739, indicated that the release kinetic of BTZ followed the Korsmeyer–Peppas model.

The application of Ca5B2SiO10:Eu3+ and YAl3B4O12:Ce3+,Mn2+ in dual-layer remote phosphor to enhance lumen output and color quality of WLEDs

This study proposes a dual-layer remote phosphor structure, comprised of a green or a red phosphor layer and a yellow YAG:Ce3+ phosphor layer, to enhance color rendering index (CRI) and color quality scale (CQS) of white light-emitting diodes (WLEDs). The phosphors used in this study are green phosphor YAl3B4O12:Ce3+,Mn2+ and red phosphor Ca5B2SiO10:Eu3+. Besides, the applied WLED structure has the color temperature of 8500 K. The study demonstrates the idea of placing a green phosphor YAl3B4O12:Ce3+,Mn2+ or a red Ca5B2SiO10:Eu3+ phosphor layer on the yellow phosphor YAG:Ce3+ one. After that, the suitable concentration of Ca5B2SiO10:Eu3+ resulting in the highest color quality is determined. The obtained results showed that Ca5B2SiO10:Eu3+ is advantageous to CRI and CQS. Particularly, the values of CRI and CQS increased following the growth of Ca5B2SiO10:Eu3+ concentration, due to the rise in red light components inside WLED’s packages. Meanwhile, the luminous flux is benefited by the added green YAl3B4O12:Ce3+,Mn2+ phosphor. However, there are decreases in lumen output and color quality when the concentrations of Ca5B2SiO10:Eu3+ and YAl3B4O12:Ce3+,Mn2+ rise over the corresponding levels. This result is proved via using Mie-scattering theory and Lambert-Beer's law. In short, the findings of the research paper are valuable references for high-light-quality WLEDs fabrication.

Improvement of double-layer phosphor structure WLEDS in color homogeneity and luminous flux

The concept of the analysis is to put a CaAl2O4:Mn2+ green phosphor layer on top of the YAG:Ce3+ yellow phosphor layer. After that, find the added CaAl2O4:Mn2+ concentration appropriate for the highest luminous flux (LF) and color homogeneity (CH). In this analysis, five equivalent WLEDs were applied but with distinct color temperatures, including 5600 K - 8500 K. The findings showed that CaAl2O4:Mn2+ brings great benefits to increase not only the luminous flux but also the color homogeneity. Especially, the higher the CaAl2O4:Mn2+ concentration, the more the luminous flux released by WLEDs, owing to the risen content of the light of green in WLEDs. Nevertheless, as the CaAl2O4:Mn2+ concentration raised significantly, a small reduction in the color rendering metric (CRI) and color quality scale (CQS) occurred. This is supported by simulation and calculation according to the theory of Monte Carlo. The paper results are the crucial contribution to the manufacture of WLEDs with better optical performance and color homogeneity of remote phosphor configurations.

Enhancing light scattering effect of white LEDs with ZnO nanostructures

Pc-LEDs, the lighting method that blends blue LED light with yellow light from phosphor to discharge white radiation, is one of the most advance known for high lumen output. However, pc-LEDs has inferior due to angular CCT deviation, which prevent pc-LEDs from reaching better performance. As a result, this research is conducted to address the need of pc-LEDs development by introducing a configuration doped with ZnO nanoparticles. The finite-difference time-domain (FDTD) method and the phosphor layer containing ZnO were applied in the experiments. The effect of ZnO-filled on the performance of color quality pc-LEDs is confirmed through calculated results. In particular, the uniformity of scattered light is improved with the presence of ZnO. In addition, ZnO particles also minimize the deviation of color temperature and enhance the color quality. Although there is a small decline in lumen output to achieve better color temperature uniformity, however, with suitable concentrations such as 0.25% N-ZnO, 0.25% S-ZnO, and 0. 75% R-ZnO, the decline is acceptable. The research on ZnO pc-LEDs demonstrates that this affordable and simple configuration can improve lighting properties and create other directions to enhance white light

The study of convex-dual-layer remote phosphor geometry in upgrading WLEDs color rendering index

<span>The white-light light-emitting diode (LED) is a semiconductor light source that usually has one chip and one phosphor layer. Because of that simple structure, the color rendering index (CRI) is really poor. Therefore, structure with double layer of phosphor and multiple chips has been studied with the phosphorus proportions and densities in the silicone are constantly changed to find the best option to improve optical properties. In research, we use red phosphor Ca5B2SiO10:Eu3+ layer to place above the yellow phosphor one, and both of them have a convex design. Then, the experiments and measurements are carried out to figure out the effects of this red phosphor as well as the convex-double-layer remote phosphor design on the LED’s performances. The measured results reveal that the light output is enhanced significantly when using convex-dual-layer structure instead of the single-layer design. Additionally, the Ca5B2SiO10:Eu3+ concentration benefits CRI and CQS at around 6600 K and 7700 K correlated color temperature (CCT). Yet, the lumen output shows a slight decline as this red phosphor concentration surpass 26% wt. Through the experiments, it is found that a double layer of chip and double phosphorus is the best structure which could support the quality of CRI and luminous flux.</span>

Morphological effect of patterned sapphire substrate on efficiency of white-light phosphor LED package

Six-facets patterned sapphire substrates (A-PSS) are manufactured by wet-etching regular semispherical patterned sapphire substrates (r-PSS). The possible crystallographic planes of the etched planes on the semi-sphere pattern is the family of (1102) plane. Metalorganic Chemical Vapor Deposition (MOCVD) GaN epitaxial LED structure was grown on the c-plane sapphire wafer, r-PSS, and A-PSS, which were further processed as horizontal LED chips. Compared to LEDs on the flat c-plane sapphire, the light output power of LEDs on r-PSS and A-PSS is enhanced by 71% and 67%, respectively. The output power of the bare LEDs decreases after the white-light LED package. Remarkably, the output power of the white-light packaged LED on the A-PSS is larger than the white-light packaged LED on the r-PSS. The Monte Carlo ray tracing simulation shows that, before and after silicone-lens encapsulating, the LEDs on r-PSS and A-PSS emit more on the top surface. However, the sidewall emission power ratio of the LED on r-PSS decreases by 3.44% after silicone encapsulating. On the other hand, the sidewall emission power ratio of the LED on A-PSS increases by 1.06% after silicone encapsulating. Note that the emission light of LEDs out of the top surface travels a longer path in the silicone lens than the emission light out of the sidewalls. Hence, more re-extracted light out of the sidewall of LED on A-PSS would be the reason for the LED on A-PSS having a less package loss and the white-light package efficiency than the LED on r-PSS. In conclusion, the light radiation distribution pattern defined by the pattern morphology of A-PSS is the key for the better white-light package efficiency of the LED on A-PSS than that of the LED on r-PSS. • The patterned sapphire substrate morphology can alter the propagation direction of the light emission. • Monte Carlo ray tracing simulation shows the emission power of top surface and sidewall vary before and after lens package. • The emission light of LEDs out of the top surface travels a longer path in the phosphor layer than the sidewalls. • The light radiation distribution defined by the pattern morphology is the key for white-light package efficiency of LED.

The effect of the grain size distribution (GSD) on the light emission performance of phosphor-based X-ray detectors

The light emission performance of indirect, phosphor-based, X-ray detectors has significantly affected image quality and diagnostic validity of the medical imaging examinations. This issue has been investigated by examining and further understanding the optical anisotropy in optical diffusion mechanisms. One crucial parameter of phosphor's structural properties that remarkably changes light distribution is the size of the phosphor particles. Up to now, the vast majority of studies have been carried out considering phosphor materials consisted of grains of equal size. In the present article an attempt is made to investigate the influence of grain size distribution (GSD) on light emitting characteristics and compare it with the condition of mean values assumptions. Our investigation was based on LIGHTAWE Monte Carlo simulation code with purpose to examine the Gd2O2S:Tb phosphor layer extracted from a mammographic Kodak Min-R 2 Cassette. The GSD was determined via scanning electron microscopy (SEM). Three cases of mean values were taken into account: (i) 1.48 μm obtained calculations of the aforementioned GSD, (ii) 2.50 μm and 7.00 μm taken from previous articles and manufacturer datasheets. Light emission was performed under different irradiation conditions (i. e., light quanta are produced by light source or an X-ray beam) and in terms of light amount and distribution. Our investigation showed that the optical distribution in real GSD was found: (a) sharper than the calculated mean value of the GSD and (b) broader than the mean value taken from the manufacturer datasheet. In particular, the deviation of GSD was found significantly high compared to 7.00 μm mean value. Examining the spatial resolution properties of both conditions, the deviation was around 16.5%, 18.2%, 14.8% assuming that the light source is situated within the phosphor mass, an X-ray beam of 20 keV and X-ray beam of 30 keV, respectively.

Developing Cost-Effective Ultrathin Reliable High Power White LED Emitters

A packaging approach for cost-effective and ultrathin high-power phosphor-based white light-emitting-diode (WLED) emitters with outstanding reliability is presented. By removing the encapsulant in the conventional method, the new approach employs a single silicone-phosphor thin layer instead of multiple phosphor layers in chip-scale package (CSP) WLED for both encapsulations, as well as wavelength conversion. It is demonstrated that the presented WLEDs exhibit superior optical and thermal performance and lifetime durability. Accordingly, the present work offers a high reliability, cost-effective alternative approach for ultrathin high power WLED emitters with significant advantages over the conventional packaging structure and chip-scale packaging methods.

Improving the optical efficiency of white light-emitting diodes based on phosphor-in-glass by a dual-layer remote phosphorus structure with the application of LiLaO<sub>2</sub>:Eu<sup>3+</sup> and CaSO<sub>4</sub>:Ce<sup>3+</sup>, Mn<sup>2+</sup>

While the remote phosphor structure is not an appropriate solution for WLED color uniformity, it is more advantageous for the luminous output of WLED than the conformal phosphor or in-cup phosphor structure. Acknowledging the ability of the remote phosphor structure, many studies have been carried out to surmount the color quality disadvantage of this structure. A dual-layer remote phosphor configuration is proposed in this research paper to acquire better color quality for WLEDs through heightening the color rendering index (CRI) and the color quality scale (CQS). The color temperature of the WLED packages this study is 8500 K. By inserting a layer of green CaSO4:Ce3+,Mn2+ or red LiLaO2:Eu3+ phosphor on the yellow YAG:Ce3+ phosphor layer, the phosphor structure configuration can be constructed. Then, to get the best color quality, the concentration of added phosphor LiLaO2:Eu3+ would be changed. The findings showed the rise of CRI and CQS along with the LiLaO2:Eu3+, which implies the influence of LiLaO2:Eu3+ to the growth of red light components within WLEDs packages. The greater the concentration of LiLaO2:Eu3+ is, the more the CRI and CQS increase. Meanwhile, the luminous flux gains from the green phosphor CaSO4:Ce3+,Mn2+. Nevertheless, the luminous flux and color quality would decrease if the concentrations of both red LiLaO2:Eu3+ and green CaSO4:Ce3+,Mn2+ phosphors reach a certain corresponding level. Centered on the Mie-scattering theory and the law of Lambert-Beer, this result is illustrated. The findings in this research are vital references for manufacturing WLEDs with higher white light performance.

An In-Depth Study of the Boron and Phosphorous Doping of GeSn

We have investigated the in situ doping of GeSn with Ge2H6, SnCl4, B2H6 (p-type) or PH3 (n-type) at 349 °C, 100 Torr on Ge Strain-relaxed Buffers, themselves on Si(001) substrates. Our aim was to replace the boron and phosphorous doped Ge layers used in previous pin structures with GeSn:B and GeSn:P. The Sn content from Wavelength Dispersive X-ray Fluorescence (WDXRF) was constant around 6.5% for low F(B2H6)/F(Ge2H6) and F(PH3)/2*F(Ge2H6) Mass-Flow Ratios (MFRs). It fell down to 4.9% (GeSn:B) and 6.0% (GeSn:P) for higher MFRs due to the dopant precursors that catalyzed the Ge Growth Rate component. The B atomic concentrations (from Secondary Ion Mass Spectrometry (SIMS)) increased almost linearly with the MFR, reaching values of at most 6.3 × 1019 cm−3. B atoms were almost fully electrically active based on Electrochemical Capacitance Voltage (ECV) measurements. WDXRF and SIMS also gave us access to the atomic P concentrations, with values as high as 3.9 × 1020 cm−3. Maybe because of the formation of SnmPnV nanoclusters, the P electrical activation decreased for the highest flows. Only the GeSn:B layers grown at the three highest MFRs exhibited some B and/or Sn surface segregation. Otherwise, a smooth surface with a cross hatch along 〈110〉 was present.

Re-Absorption Effect Modeling for Dual-Layer Phosphor Package of White LEDs

This paper successfully establishes an optical model with dual green/red phosphor layers based on the original single-phosphor model. Since the re-absorption effect of double-layer phosphors causes spectral distortion, the model must introduce a correction mechanism for spectral re-absorption. Through the LED packaging experiment, simulation, and verification of the double-layer phosphors, we can effectively predict the ratios required for the two phosphors under different color temperatures and confirm this model's high precision and accuracy. In the future, this model can be used to analyze further the optical performance of white LEDs with different dual-layer phosphor packaging types.

(Y,Gd)BO<sub>3</sub>:Eu red phosphor for dual-layer phosphor structure to enhance the optical performance of white light-emitting diodes

Among the structures using for fabricating white light-emitting diodes (WLEDs) such as the conformal coating or in-cup geometries, the remote phosphor structure gives the highest luminous efficacy. However, in terms of color quality, its performance is not as good as the others. The red-light compensation has been reported as the effective solution for enhancing the color quality of WLEDs. Hence, this study adopted the idea and applied to the dual-layer phosphor structure. The phosphor used to boost the red color in light formation is (Y,Gd)BO3:Eu particle. The dual-layer remote phosphor structure was simulated with the red (Y,Gd)BO3:Eu phosphor layer above the original yellow phosphor YAG:Ce3+ one. The WLEDs with different correlated color temperatures of 5600 K, 6600 K and 7700K were experimented. Mie-theory and Lambert-Beer law were applied to examine the results. The growth in color rendering index (CRI) and color quality scale (CQS) with the increase of (Y,Gd)BO3:Eu phosphor concentration was observed. Nevertheless, the lumen efficacy would be degraded if the concentration was over a certain number. The information provided in this article is useful for the development of high-power WLED production with greater color quality.

Triple-layer remote phosphor structure: a selection of the higher color quality and lumen efficiency for WLEDs

To enhance color quality of glass-based phosphor-converted white light-emitting diodes (pc-WLEDs) with multi-layer remote phosphor layer structures, two phosphors, green CdS:In and red ZnS:Te,Mn, are integrated into the glass matrix and applied to the dual-layer and triple-layer WLED packages. The attained results were examined with Mie-scattering theory and Lambert-Beer law. The dual-layer showed significant enhancement in color rendering index (CRI), in the range of approximate 80-90. Meanwhile, CRI in the triple-layer was lower and stayed around 66. In terms of color quality scale (CQS), a more overall color evaluating index, triple-layer structure helps the glass-based WLED achieve higher value than the dual-layer. The triple-layer is also beneficial to the luminous efficacy, according to the experimented results. Thus, the triple-layer structure can be used to strengthen the benefit of the glass matrix used in WLED products.

Effects of remote sediment phosphor plates on high power laser-based white light sources

Phosphor-converted blue laser diodes are regarded as the next-generation high-brightness solid-state lighting sources. However, it is difficult to obtain white light with high angular color uniformity due to the Gaussian distribution of the laser light sources. Meanwhile, laser excitation power density of the light source is high, which would bring serious heating effects to the phosphor layers. In this study, a strategy has been proposed to solve the problem by using remote sediment phosphor plates. In detail, we have compared the effects of remote sediment/non-sediment phosphor plates to the phosphor-converted blue laser diodes on the overall light output characteristics, angular optical distribution properties, as well as their thermal performance. The emission from sediment phosphor samples has been found more divergent, and angular deviation in the correlated color temperature of the emitted light could be greatly reduced from 1486 to 294 K, yet with only 5% luminous flux loss, as compared to non-sediment phosphor samples. Most importantly, the sediment phosphor sample pushes the power damage threshold up to 588.1 W/cm2 (non-sediment sample: 512.3 W/cm2). Our work has demonstrated the sediment phosphor plates would ameliorate the angular color uniformity for the laser-based lighting source, while extending its lifespan with improved thermal stability.

Feasibility study of a photochromic diarylethene film as a clinical dosimeter for kV X-rays

Radiochromic film (RCF) is commonly used as a measurement tool in radiation therapy and diagnostic X-ray imaging. However, the results are not immediately available. This study establishes the workflow of a new diarylethene (DAE) film dosimetry and investigates the film response versus dose against kV X-rays, with the results immediately available for analysis. The DAE film includes a phosphor layer (BaFCl:Eu), a DAE layer, and a UV cut filter. The workflow of the DAE film dosimetry is as follows: (1) irradiation, where the absorbed doses were between 0.1 and 5.0 Gy at 150 kVp X-ray; (2) scanning with blue excitation light (λ = 465 nm) within 1 h of irradiation to obtain a fluorescence intensity map; and (3) analysis of the relationship between the fluorescence intensity and the absorbed dose, and then comparison between such relationship and that between the optical density and absorbed dose of the RCF. Results show that the fluorescence intensity of the DAE film increased with increasing dose. Moreover, the DAE film had a roughly linear response, while the response of RCF was logarithmic (Pearson's correlation coefficients are 0.979 and 0.843, respectively). The DAE film is feasible as a clinical dosimeter of choice.

MgCeAl11O19:Tb3+ and Mg8Ge2O11F2:Mn4+ in enhancing the color quality of remote phosphor LED

As the name infers, the triple-layer remote phosphor (TRP) has 3 phosphor layers includes the red Mg8Ge2O11F2:Mn4+ phosphor layer on the top, the green MgCeAl11O19:Tb3+ phosphor layer in the middle, and the yellow YAG:Ce3+ layer at the bottom and is mentioned as a solution to increase the chromaticity and luminescence adequacy of the white LEDs (WLEDs) in this article. As to control the red light for higher value achieve in the color rendering index (CRI), using red Mg8Ge2O11F2:Mn4+ phosphor in the TRP structure is recommended. All the outcomes indicate that when red phosphor Mg8Ge2O11F2:Mn4+ concentration grows the CRI gets higher values, and drastically declines when the concentration of green phosphor MgCeAl11O19:Tb3+ increases. As the same time, applying the green MgCeAl11O19:Tb3+ phosphor layer to manage the green light as it can make the luminous efficacy (LE) of WLEDs increase. In particular, the index of LE can also be improved over 40% by limiting the scatter of light and putting in green light. Moreover, to preserve the average correlated color temperature (ACCT) stable at 8500K, the yellow YAG:Ce3+ concentration must be cut down as the concentration of red and green phosphor rise.

Using flat phosphor layer in dual-layer remote phosphor configuration to improve luminous efficacy

The phosphor layer shape and components distances are the subjects proposed to advance the quality of WLEDs in this article. The two distances, between phosphor layers (d1) and between the phosphor layer and the LED chip (d2) in Flat dual-remote phosphor (FDRP) and Concave dual-remote phosphor (CDRP) were examined by experiments to determine their impacts on WLEDs lighting performances. The results suggest that FDRP is a better option than CDRP for lighting performance. In each respective structure, the distances influence the lighting capacity and color output whenever they fluctuate. Therefore, to effectively control and study this phenomenon, the correlated color temperature is maintained at 8500 K, and the concentration of phosphor material is altered while the distances are changing. When d1 and d2 are at the starting value of 0, the recorded lumen output and chromatic performance of lighting devices are the lowest and begin to increase as d1 and d2 expand. Bigger d1 and d2 mean bigger scattering area and better chromatic light integration, which leads to higher color quality. Detailed results present that optimal values of d1 or d2 for the highest lumen output of 1020 lm are 0.08 mm or 0.63 mm, respectively. Meanwhile the lowest color deviation is accomplished with d1=0.64 mm or d2=1.35 mm.

Characteristics of Perovskite Solar Cells with ZnGa2O4:Mn Phosphor Mixed Polyvinylidene Fluoride Down-Conversion Layer

To reduce the manufacturing cost of perovskite solar cells, soda-lime glass and transparent conducting oxides such as indium tin oxide and fluorine-doped tin oxide are the most widely used substrates and lighttransmitting electrodes. However, the transmittance spectra of soda-lime glass, indium tin oxide, and fluorinedoped tin oxide show that all light near and below 330 nm is absorbed; thus, with the use of these substrates, light energy near and below 330 nm cannot reach the perovskite light-absorbing layer. It is expected that the overall solar cell can be improved if the wavelength can be adjusted to reach the perovskite solar cell absorbing layer through down-conversion of energy in the optical wavelength band. In this study, a polyvinylidene fluoride transparent film mixed with a ZnGa2O4:Mn phosphor was applied to the incident side of the perovskite solar cell with the intent to increase the light conversion efficiency without changing the internal bandgap energy and structure. By adding a phosphor layer to the external surface of PSC exposed to incident light, the efficiency of the cell was increased by the down-conversion of ultraviolet light (290 nm) to the visible region (509 nm) while maintaining the transmittance. To manufacture the perovskite solar cell, a TiO2-based mesoporous electron transport layer was spin-coated onto the substrate. The perovskite layer used in this experiment was CH3NH3PbI3 and was fabricated on a TiO2 layer. Spiro-OMeTAD solution was spin-coated as a hole-transport layer.