| 摘要 |
PROBLEM TO BE SOLVED: To reduce band like uneven brightness caused on an observation surface. SOLUTION: This surface illuminating device disposed to cover the surface of a reflection type liquid crystal element is so constructed that a light source part is disposed along the side end face of a transparent substrate formed of light transmitting material, and a groove part having a substantially triangular section is formed on the transparent substrate. At this time, the groove part is gradually increased in depth as it separates from the light source part so that the quantity of light caused by reflection at the groove part is equal to the quantity of light depending on the distance from the light source part over the whole surface of the transparent substrate, and the groove parts different in depth are provided so as to reduce an area where the groove parts of the same depth are continuously formed, whereby band like uneven brightness is reduced. |
