Amplitude Filter와 Phase Filter가 결합된 광학계의 결상특성

Abstract

We chose Bessel beamu[$J_o(ar)}$)l in order to investigate image forming property of the optical system with combined filter of amplitude and phase(CFAP). This paper investigated numerically the influence of number of nodes of these beams on the PSF, encircled energy(E), transmission ratio(TR), gain((;) for an aberrated(1aberration-free) optical system. These results showed that the property of PSF differ considerably from the one of the existing amplitude filter and that Bessel beam has super compensating effect for an optical system with spherical aberration. Particularly, the Bessel beam has less the size of central spot than the radius of Airy disk, this result can therefore be applied to the fabrication of semiconductor device.

Amplitude filter와 phase filter가 결합된 CFAP(Combined Filter of Amplitude and Phase)의 결상 특성을 조사하기 위해 Bessel beam을 도입하였다. 이 논문에서는 무수차계와 수차를 포함하는 광학계에 대한 PSF와 encircled energy(E), transmission ratio(TR), gain(G)을 Bessel beam의 node수에 따라 계산하였다. 이 결과 Bessel beam은 amplitude filter와 다른 PSF 특성을 보였으며, 또한 구면수차가 포함된 경우 compensating effect가 크게 나타났다. 특히 Bessel beam의 central spot의 size가 Airy disk 반경보다 적게 나타나므로, 고집적 반도체 소자 제작에 이용가능하리라 생각된다.

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