초록 ▼

An illuminated sign, readable during the night or day, and suitable for use as a house number display, uses a single illuminatable panel, on which a number of stencils are plac critical flicker frequency ed. Each stencil is a rectangular piece of opaque material, such as plastic or metal, in which a

An illuminated sign, readable during the night or day, and suitable for use as a house number display, uses a single illuminatable panel, on which a number of stencils are plac critical flicker frequency ed. Each stencil is a rectangular piece of opaque material, such as plastic or metal, in which a central cutout is made in the shape of a number. Several of these stencils are arrayed in front of the illuminatable panel, so that only the light coming through the central cutouts is visible through the stencils. The illuminatable panel is made of an array of LED's, with a diffuser to produce a uniform illumination, and is powered by one or more batteries. A light detector senses the onset of dusk, which activates the illuminatable panel, turning it on, and leaving it on for four or more hours. A constant-current electronic system powers the LEDs, which are pulsed on and off at a speed greater than 90 Hz, which makes the sign appear to the human eye as constantly illuminated. A timer leaves the illuminatable panel illuminated only for a few hours, in order to maximize the life of the batteries.

대표청구항 ▼

1. An illuminated sign, comprising:(a) one or more batteries; (b) an illuminatable panel powered by the batteries, and further comprising a multiplicity of LEDs; switching means which switch the LEDs on and off at a pulse rate beyond the critical flicker fusion frequency; which vary the pulse rate,

1. An illuminated sign, comprising:(a) one or more batteries; (b) an illuminatable panel powered by the batteries, and further comprising a multiplicity of LEDs; switching means which switch the LEDs on and off at a pulse rate beyond the critical flicker fusion frequency; which vary the pulse rate, which cause the LED's to remain on for an on period after being switched on, and which vary the duration of said on period; (c) light diffusing means disposed in front of the illuminatable panel; and (d) one or more opaque stencils each containing one or more cutouts of a character through which the illuminatable panel is visible, so that the appearance of the sign is of illuminated characters corresponding to the stencils when the illuminatable panel is illuminated.