非球面閃耀式微光柵 (micro-aspheric blazed grating)的結構主要結合閃耀式光柵高階繞射之高效率分光能力與非球面鏡近似無像差之聚焦功能。論文中首先推導出此光學元件之繞射分光與多項式非球面鏡聚焦公式，進而分析討論入射狹縫(entrance slit)、光柵繞射及曲面像差等三個主要影響光學繞射分光系統之解析力(resolving power)，研究發現在適當大小入射狹縫與高階繞射閃耀式光柵下，利用多項式非球面聚焦鏡，即使於紅外光區域內，仍可獲得超高解析度之分光能力。此光柵除了設計於經線(meridional)之多項式非球面聚焦功能外，尚包含緯線聚焦(sagittal focus)能力，具有超高分波多解多工器(demultiplexer)功能，將有機會成為高密度分波多工(dense wave- length division multiplexing，DWDM)光纖通訊系統中之重要光學元件。另外非球面閃耀式微光柵可藉由高精度之灰階光罩(gray level mask)來轉印製成，因此本論文針對自製之可調變雷射書寫系統(laser direct writer，LDW)於灰階光罩製作上精度的提昇加以分析改進。 A novel micro-aspheric blazed grating integrated with high-efficiency and high-resolution dispersion capability of blazed grating and nearly no aberration limit of aspheric focusing has been proposed. In this thesis, the blazed grating equation and the aspheric polynomial formula of this optical diffractive element are derived, and then the resolution mainly caused by the size of entrance slit, the capability of grating dispersion, surface aberration are discussed. With a suitable size of the entrance slit and a higher diffraction order blazed function, this diffractive element based on a fourth-order-polynomial surface can achieve an ultrahigh resolving power even in the entire infrared region. The optical element provides both meridional aspheric focusing and sagittal focusing for abnormal incident polychromatic light beam. The novel grating has been designed as an optical demultiplexer for use in dense wavelength division multiplexing (DWDM) optical communication. The micro-aspheric blazed grating template can be made of a gray level mask by using a high-precision laser direct writer (LDW) with light intensity modulation of 1% precision. Therefore, the performance of a home-made LDW that is already to fabricate optical masks for simple diffractive elements is needed to be improved.
