# 구배형 굴절률 반사방지막 연구

• Kim, Chang-Bong (Division of Radio-wave Engineering, Kongju National University)
• 김창봉 (공주대학교 정보통신공학부 전파전공)
• Accepted : 2017.05.12
• Published : 2017.05.31
• 39 6

#### Abstract

The various techniques proposed previously to obtain a good antireflection(AR) coating induce a scattering of incident light by nanoparticles or control the refractive index by using different materials. This paper compares a suggested graded index profile with the quintic index profile previously suggested for producing an index profile that gives good performance from an AR coating. We assume the structure of the AR coating has three, six, and nine layers with 180 nm total thickness. The wavelength of incident light ranges from 300 nm to 1100 nm. We use the transfer matrix theory for a single layer to obtain the reflectivity of three, six, and nine layers. The reflectivity of two different index profiles with three, six, and nine layers is compared. As a result, the suggested graded index profile shows lower reflectivity than the quintic index profile with three layers, especially in the wavelength range from about 600 nm to 1100 nm. Therefore, we expect that these results can be applied to optical devices and filters in the range from visible(red) to near infrared.

#### Keywords

Antireflection Coating;Transfer Matrix;Index Profile;Reflectivity

#### Acknowledgement

Supported by : 공주대학교

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