Design and fabrication of planar blazed grating for LC rear-projection display system

Design and fabrication of planar blazed grating for single-panel LC rear-projection display system are presented. The structure of planar blazed grating is designed to disperse the incident visible light and achieve a high diffraction efficiency in a specified direction corresponding to a specified order. Two economical fabrication methods are studied. By ultrahigh-precision cutting technology, the continuous-relief planar gratings with the structure line width 0.96 and 1.5 μm are fabricated. In addition, other grating with the structure line width 2.5 μm is fabricated by using excimer laser dragging. Comparing the two fabrication results, the second one has smoother surface and smaller spacing error but the vertex angle is not enough sharp and the structure line width is limited.