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Journals / Mühendislik Bilimleri ve Araştırmaları Dergisi / 2024 / Cilt: 6 Sayı: 2

Effects of LED Phosphor Technologies Used in Television Backlight Systems on Reliability and Color Accuracy

Televizyonların Arka Işık Sistemlerinde Kullanılan LED Fosfor Teknolojilerinin Güvenirlik ve Renk Doğruluğu Üzerine Etkileri

Olcay Saribiyik(YILDIZ TEKNİK ÜNİVERSİTESİ)0000-0001-8214-5980
Ramazan Ayaz(YILDIZ TEKNİK ÜNİVERSİTESİ)0000-0002-6201-1181
Pages
236–245
Publication Date
2024-10-29
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AI Summary & Key Takeaways

AI Insight
⚡ TL;DR(Too Long; Didn't Read)

Thus, the impact of phosphor types on the durability of LEDs is compared.

📌 3 Key Takeaways

🎯
Objective & Hypothesis:Phosphor layers used in LEDs enable a blue-emitting LED chip to emit light in white tones.
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Key Findings & Data:Two primary types of phosphors are used in the industry, YAG (Yttrium Aluminum Garnet) and KSF (K2SiF6+).
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Conclusion & Impact:Thus, the impact of phosphor types on the durability of LEDs is compared.
🔬Design:Araştırma Makalesi
📍Scope:Comprehensive Sample
⚙️Variables:LED Televizyon · Fosfor Teknolojisi · Televizyon Arka Işık Sistemi

Abstract

Phosphor layers used in LEDs enable a blue-emitting LED chip to emit light in white tones. Two primary types of phosphors are used in the industry, YAG (Yttrium Aluminum Garnet) and KSF (K2SiF6+). These phosphors offer different color spectrums while also possessing varying durability characteristics. This study examines LED bars composed of LEDs with YAG and KSF phosphors, commonly used in televisions, for reliability under different environmental conditions and driving currents. The ambient temperature is kept high in the first scenario while applying a low LED current. In the second scenario, a low ambient temperature with a high LED current is applied. Microscopic images of each LED are taken both before and after the tests in both scenarios. Additionally, during the tests, periodic checks are conducted to record the junction temperatures of the LEDs. The point at which each LED failed is documented, and reliability analysis is performed using the Reliasoft program to estimate their approximate lifetimes. Thus, the impact of phosphor types on the durability of LEDs is compared.

Özet

LED’lerde kullanılan fosfor tabakaları mavi renkte ışıma yapan bir LED çipin beyaz tonlarında ışıma yapmasını sağlamaktadır. Sektörde başlıca YAG (Yttrium Aluminum Garnet) ve KSF (K2SiF6:Mn4+) olmak üzere iki çeşit fosfor türü kullanılmaktadır. Kullanılan bu fosforlar farklı renk yelpazesi sunabilmektedir ancak bunun yanında farklı dayanım özelliklerine de sahiptirler. Bu çalışmada, televizyonlarda kullanılan YAG ve KSF fosforlu LED’lerden oluşan LED barlar farklı ortam koşulları ve sürme akımlarında çalıştırılarak güvenirlik açısından incelenmiştir. Birinci durumda ortam sıcaklığı yüksek tutulurken düşük LED akımı uygulanmış, ikinci durumda ise düşük ortam sıcaklığında yüksek LED akımı uygulanmıştır. Her iki durumda da test öncesi ve test sonrası her bir LED’in mikroskop görüntüleri alınmıştır. Ayrıca her durumda LED’ler periyodik olarak kontrol edilerek LED’lerin jonksiyon sıcaklıkları kaydedilmiştir. Kontrol sırasında LED’lerin testin kaçıncı saatinde bozulduğu kayıt altına alınarak Reliasoft programında güvenilirlik analizi yapılmış ve yaklaşık ömürleri tahmin edilmiştir. Böylece fosfor türlerinin LED’lerin dayanımına olan etkisi karşılaştırılmıştır.

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Cite This Article

Saribiyik, O., Ayaz, R. (2024). Effects of LED Phosphor Technologies Used in Television Backlight Systems on Reliability and Color Accuracy. Mühendislik Bilimleri ve Araştırmaları Dergisi, Cilt: 6 Sayı: 2, 236–245. https://doi.org/10.46387/bjesr.1552661

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