| 摘要 |
PURPOSE:To prevent the vignette of the pattern by setting the space between the TN liquid crystal layer and the surface of the reflecting plate to 100mu or less. CONSTITUTION:A pair of upper and lower deflecting plate 15 and 16 form the DC deflecting field, and thus the light given from light source 18 transmits through the deflecting plates and then reaches viewer 19 after being reflected by reflecting plate 17. When the voltage is applied to part 20 of TN liquid crystal 13, the transmitted light of part 20 is erased and thus the pattern is observed. Generally, the light source and the viewer are positioned at different places to the reflecting plate, and accordingly shadow 21 of the pattern as well as pattern 20 can be observed at the shifted positions to each other to disturb the display. To get rid of the disturbance, the distance between liquid crystal 13 and plate 17 is reduced. With the thickness of about 200mu for the lower glass plate, the pattern overlaps its shadow imperfectly to impair the observation of the display. Thus, the thickness is reduced approximately to 100mu or less to secure a perfect coincidence between the pattern and its shadow. As a result, a sufficiently high contrast is obtained even with use of the light-colored deflecting plate featuring a small light erasion rate, thus obtaining a bright display screen and a thick viewfield angle. |
