Solid State Light Sheet Having Wide Support Substrate and Narrow Strips Enclosing LED Dies in Series

Abstract

A solid state light sheet and method of fabricating the sheet are disclosed. In one embodiment, bare LED chips have top and bottom electrodes, where the bottom electrode is a large reflective electrode. The bottom electrodes of an array of LEDs (e.g., 500 LEDs) are bonded to an array of electrodes formed on a flexible bottom substrate. Conductive traces are formed on the bottom substrate connected to the electrodes. A transparent top substrate is then formed over the bottom substrate. Various ways to connect the LEDs in series are described along with many embodiments. In one method, the top substrate contains a conductor pattern that connects to LED electrodes and conductors on the bottom substrate.

1 - 20 . (canceled) 
     
     
         21 . A lighting device comprising
 an elongate substrate having first and second surfaces;   multiple pump light-emitting elements (LEEs) electrically connected in series and arranged along the elongate substrate, each of the multiple pump LEEs configured to generate pump light during operation, each LEE having a first face and an opposing second face and configured to output the pump light through the first face and reflect the pump light at the second face; and   a phosphor material disposed on both the first and second surfaces of the elongate substrate, the phosphor material being configured to convert at least a portion of the pump light emitted by the pump LEEs to converted light,   wherein the lighting device is configured to output light into the ambient environment away from the first and second surfaces of the elongate substrate, the outputted light comprising at least some of the pump light and at least some of the converted light.   
     
     
         22 . The lighting device of  claim 21 , wherein the LEEs are disposed on the first surface of the elongate substrate. 
     
     
         23 . The lighting device of  claim 22 , wherein the first face of at least some of the LEEs face the first surface of the elongate substrate. 
     
     
         24 . The lighting device of  claim 22 , wherein the second face of at least some of the LEEs face away from the first surface of the elongate substrate. 
     
     
         25 . The lighting device of  claim 22 , wherein the first face of at least some of the LEEs face away from the first surface of the elongate substrate. 
     
     
         26 . The lighting device of  claim 22 , wherein each LEE comprises a pair of edge walls connecting the first and second faces and the phosphor material disposed on the first surface of the elongate substrate is located adjacent the edge walls of the LEEs. 
     
     
         27 . The lighting device of  claim 21 , wherein the phosphor material is contained in a phosphor layer. 
     
     
         28 . The lighting device of  claim 27 , wherein the phosphor layer comprises phosphor material positioned adjacent each LEE on the opposing side of the elongate substrate from each LEE. 
     
     
         29 . The lighting device of  claim 27 , wherein the phosphor layer comprises discontinuous portions of phosphor material adjacent each LEE on the opposing side of the elongate substrate from each LEE. 
     
     
         30 . The lighting device of  claim 27 , wherein the phosphor layer is flat. 
     
     
         31 . The lighting device of  claim 27 , wherein the phosphor layer is shaped. 
     
     
         32 . The lighting device of  claim 27 , wherein the phosphor layer adjacent each LEE has an area that is the same or larger than an area of the LEE. 
     
     
         33 . The lighting device of  claim 21 , wherein the pump light is blue light. 
     
     
         34 . The lighting device of  claim 33 , wherein the output light is white light. 
     
     
         35 . The lighting device of  claim 21 , wherein each LEE is a light-emitting diode (LED) chip.