結構光深度感測可藉由投射已知光點圖案，並分析光點於物體表面上的位置變化來取得深度資訊。傳統結構光投影系統通常需要透鏡或繞射光學元件進行光場調控，使系統在微型化與整合上受到限制。超穎介面透過次波長奈米結構控制光的相位、振幅與傳播方向，超穎介面厚度薄且結構緊湊，可作為結構光投影系統的光場調控元件。本論文提出結合動量操控與準直陣列之超低畸變結構光設計，並以940 nm VCSEL陣列作為光源。透過動量空間設計，配合局部準直相位，使VCSEL陣列的出射光導向目標投影區域，形成低畸變結構光點陣。在製程上，本論文比較二氧化矽硬遮罩與鉻金屬遮罩兩種製程方式。結果顯示，鉻金屬遮罩製程可減少製程步驟，避免頂層遮罩殘留造成的結構偏差，並提高奈米結構的側壁垂直度。實際遠場投影結果顯示，光點分布與模擬結果相對應，量測所得之結構光畸變率為1.99%，且能搭配單一相機進行深度感測。
結果顯示，藉由動量操控與準直相位整合後，可在單一超穎介面中實現低畸變結構光點陣，作為單一相機深度感測的投影光源。若未來進一步將超穎介面與VCSEL陣列光源整合，並根據光源座標配置與發散角，調整準直區域尺寸及準直焦距，使各光源於元件平面上的主要能量分布與對應準直區域相匹配，可減少光能進入相鄰區域，改善光束的準直程度，形成更清晰且排列規則的結構光點陣。

Structured-light depth sensing obtains depth information by projecting a known dot pattern and analyzing changes in the dot positions in the captured image. However, conventional structured-light projection systems usually require additional lenses or diffractive optical elements, thereby limiting system miniaturization.
In this thesis, an ultra-low-distortion structured-light generator based on a metasurface is proposed. Momentum engineering is used to guide the light from a 940 nm vertical-cavity surface-emitting laser (VCSEL) array toward the target projection regions, while a collimator array is introduced to reduce the intrinsic divergence of the VCSEL beams. Compared with the silicon dioxide hard-mask process, the chromium metal mask process simplifies fabrication, avoids structural differences caused by residual top-mask material, and results in nanostructures with higher sidewall verticality.
The fabricated metasurface generates a far-field structured-light pattern corresponding to the simulation results. The measured distortion is 1.99%. The projected dot pattern is also used for single-camera depth sensing. These results demonstrate the feasibility of combining a metasurface with a VCSEL array for miniaturized structured-light projection systems.

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