| 摘要 |
PROBLEM TO BE SOLVED: To provide a planar illuminator in simple structure improving luminance and reducing luminance non-uniformity while considering the prevention of environment pollution by using a mercury-free nonelectrode type cold cathode-ray tube(CRT). SOLUTION: A light source is a pipe-shaped lamp having an almost circular cross section and has two band-shaped electrodes opposed in diameter direction along with the lengthwise direction of a lamp surface and on the bottom of casing 2, with which one surface side is opened and the inner surface is a white and opaque light diffusing body, composed of an internal non-electrode type cold CRT 1 radiating illuminating light from one gap terminal between two relevant electrodes, plural internal non- electrode type cold CRT 1 are arranged at almost equal intervals while turning the radiation parts of the internal non-electrode type cold CRT 1 toward the opening surface of that casing. Between these internal non-electrode type cold CRT, light reflectors 3 and 4 are formed while having lower parts lowered on the bottom side of the casing 2 a little rather than the band-shaped electrodes of the internal non- electrode type cold CRT, having higher parts at the central section between the adjacent internal nonelectrode type cold CRT and being inclined into projection at an angle 1.2 to 15. The opening surface of the casing 2 is covered with a milky light diffusing plate 5 having the regularly reflective glossy face of an inner surface. |
