Opteolectronic devices

Abstract

A light emitting semiconductor device mounted on a heat sink and having a heat pipe located on its upper surface. The heat pipe comprises a sealed cylindrical member of transparent or translucent material having a wick disposed down the side and along the bottom thereof. The heat is partially filled with a liquid which is placed under a partial vacuum to reduce its boiling point. A bundle of optical fibres may be provided within the heat pipe, with the gaps created between the optical fibres providing an efficient capillary action within the heat pipe for transport of vapour to the cool end of the pipe and for transport of condensed coolant to the hot end of the pipe.

1 - 14 . (canceled)  
   
   
       15 . A heat pipe for use in extracting heat from a semiconductor light source having an active region, the heat pipe comprising one of a transparent and translucent members said member formed of a thermally conductive material and defining an optical transmission path therethrough, the heat pipe being adapted to be located proximate to the active region of the semiconductor device to extract heat, when in use.  
   
   
       16 . A heat pipe according to  claim 15  wherein said optical transmission path is provided by means of a channel which runs through the heat pipe.  
   
   
       17 . A heat pipe according to  claim 16 , wherein said channel is arranged to receive optical transmission means.  
   
   
       18 . A heat pipe according to  claim 15 , wherein the one of the transparent and translucent member comprises a hollow pipe with sealed ends.  
   
   
       19 . A heat pipe according to  claim 15 , wherein the heat pipe is at least partially filled with a cooling fluid.  
   
   
       20 . A heat pipe according to  claim 19 , wherein said cooling fluid is placed under a partial vacuum.  
   
   
       21 . A heat pipe according to  claim 15 , which transports liquid by capillary action.  
   
   
       22 . A heat pipe according to  claim 16 , wherein a bundle of optical fibres is disposed in said channel.  
   
   
       23 . A heat pipe according to  claim 17 , wherein a bundle of optical fibres is disposed in said channel.  
   
   
       24 . A heat pipe according to  claim 23 , comprising a cool end and a hot end, the hot end closer to the active region of the semiconductor device than the cool end, and wherein said optical fibres are substantially circular in cross-section, said optical fibers defining gaps between said optical fibres, said gaps defining capillary channels by which heated coolant fluid, said coolant fluid being in the state of at least one of liquid and vapor, can be transported towards the cool end of the heat pipe, and by which condensed liquid can be transported from the cool end of the heat pipe back to the hot end.  
   
   
       25 . A heat pipe according to  claim 24 , wherein said optical fibres are located around the periphery of the heat pipe such that a channel is defined through the centre of the pipe, by means of which coolant fluid can flow.  
   
   
       26 . A semiconductor light source comprising a heat pipe according to  claim 15 .  
   
   
       27 . A semiconductor light source according to  claim 26 , further comprising a condenser.  
   
   
       28 . A combination heat pipe and semiconductor light source, the semiconductor light source having an active region, the heat pipe for use in extracting heat from the semiconductor light source, the heat pipe comprising a member formed of a thermally conductive material and defining an optical transmission path therethrough, the heat pipe being adapted to be located proximate to the active region of the semiconductor device to extract heat, when in use.  
   
   
       29 . A combination heat pipe and semiconductor light source according to  claim 28 , wherein said optical transmission path is provided by means of a channel which runs through the heat pipe and wherein said channel is arranged to receive a bundle of optical fibers, and wherein the heat pipe has a coolant fluid therein.  
   
   
       30 . A combination heat pipe and semiconductor light source according to  claim 29 , wherein the bundle of optical fibers defines a plurality of gaps and wherein the gaps define capillary channels for flow of the coolant fluid.  
   
   
       31 . A combination heat pipe and semiconductor light source according to  claim 15 , wherein the heat pipe is at least partially filled with coolant fluid.  
   
   
       32 . A method of cooling a light emitting diode having an active region, the method comprising the steps of placing a heat pipe as claimed in  claim 15  proximate the active region.