Sign 1 has frame 13 attaching to base 9 and supporting character plates 4. Casing 11 attaches to frame 13 and holds character plates 4 against frame 13. Light assembly 15 and base 9 backlight character plates 4. Backlight is diffusion chamber 17 sidelit by light assembly 15. Casing 11 hides access to...http://www.google.ca/patents/US20040201565?utm_source=gb-gplus-sharePatent US20040201565 - Address and/or alarm indicator sign
