Lighting device employing a light guide plate and a plurality of light emitting diodes

Abstract

The present invention relates to a lighting device including a light guide plate, and at least one array of light emitting diodes (LEDs), which LEDs are accommodated in holes arranged in the light guide plate. In some embodiments, the device is characterized by an array of lenses arranged such that light emitted by the LEDs passing the lens array is at least partly directed towards areas of the light guide plate free from holes.

1 . A lighting device, comprising:
 a light guide plate defining a plurality of holes, at least one array of light emitting diodes (LEDs) at least partially disposed in the holes; and   an array of lenses arranged such that light emitted by the LEDs passing the lens array is directed to pass between the LEDs in the array of LEDs, wherein the lens array is placed between one LED array and a reflective edge of the light guide plate such that light emitted by the LEDs in the array and reflected by the reflective edge is directed by the lens array to pass between the LEDs in the array.   
     
     
         2 . The device according to  claim 1 , wherein the array of lenses comprises at least one row of positive lenses. 
     
     
         3 . The device according to  claim 1 , wherein, for at least one lens in the array of lens, the lens pitch is about ½ of the LED pitch and is smaller than about ½ of the lens radius. 
     
     
         4 . The device according to  claim 1 , wherein the LEDs are aligned with every second junction between two adjacent lenses in the lens array. 
     
     
         5 . The device according to  claim 1 , wherein the holes are substantially cylindrical, and the LEDs are side-emitting omnidirectional LEDs. 
     
     
         6 . A lighting device, comprising:
 a light guide plate defining a plurality of holes, at least one array of light emitting diodes (LEDs) at least partially disposed in the holes; and   an array of lenses arranged such that light emitted by the LEDs passing the lens array is directed to pass between the LEDs in the array of LEDs, wherein, for at least one lens in the array of lens, the lens pitch is about ½ of the LED pitch and is smaller than about ½ of the lens radius   
     
     
         7 . The device according to  claim 6 , wherein the lens array is placed between one LED array and a reflective edge of the light guide plate such that light emitted by the LEDs in the array and reflected by the reflective edge is directed by the lens array to pass between the LEDs in the array. 
     
     
         8 . The device according to  claim 7 , wherein the LEDs are aligned with every second junction between two adjacent lenses in the lens array. 
     
     
         9 . The device according to  claim 6 , wherein the holes are substantially cylindrical, 
     
     
         10 . The device according to  claim 6 , wherein the LEDs are side-emitting omnidirectional LEDs.