在電腦產生全像技術(Computer-generated hologram, CGH)中，編譯完電腦產生全像後，需要使用空間光調製器(Spatial Light Modulator, SLM)來進行影像重建，並使用雷射光作為重建光源，然而，重建的影像品質往往受到零階光以及雷射光斑兩項干擾而下降。其中，零階光是未經過正確相位調製的光束，保持其原始相位及震幅，在重建全像影像時，零階光會降低圖像對比度和清晰度，並對目標重建影像產生干擾；而雷射光為高同調性之光源，容易受到空氣中的塵埃等因素影響，使光波產生不規則變化的振幅及相位，這些波相互疊加後，產生建設性干涉及破壞性干涉，而在重建影像中形成隨機亮暗光點的光斑，雷射光斑會使重建影像亮度不均，且會掩蓋重建影像的細節，造成影像品質和清晰度降低。
為了解決上述兩項問題，本研究率先提出零階光再利用，除了使重建影像不再受零階光干擾，並且使影像平均光強度增強57%~62%。此外，我們在零階光再利用架構中，我們也率先提出使用震動反光鏡來降低光斑，可使重建影像的光斑對比度降至3.8%~9.3%，使重建影像品質獲得提升。

Computer-generated hologram (CGH) commonly utilizes spatial light modulator (SLM) and laser for image reconstruction. However, the quality of the reconstructed image is often compromised by two interferences: laser speckle and zero-order beams.
Zero-order beam, an unmodulated beam with its original phase and amplitude, significantly affects the contrast and clarity of the reconstructed image. On the other hand, laser light, known for its high coherence, is susceptible to irregular variations in amplitude and phase caused by environmental factors such as dust in the air. When these waves superpose, constructive and destructive interferences occur, resulting in random bright and dark spots called speckles. These laser speckles cause uneven brightness in reconstructed images and obscure finer details, thus reducing the image quality and clarity.
To address these issues, this study proposes the novel concept of zero-order beams reusing. By reusing zero-order beams, not only is the reconstructed image no longer affected by zero-order beams interference, but also the image average intensity is enhanced by 57%~62%. Furthermore, within the framework of zero-order beams reusing, we are the first to propose the use of vibrating reflectors to reduce speckle, which can reduce the speckle contrast of reconstructed images to 3.8%~9.3%, leading to improved image quality.

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