Abstract:
An LED module includes an LED and a light-guiding board. The light-guiding board includes a light-incident face facing the LED, a light-emergent face, a light-reflecting face opposite to the light-emergent face, and a light-converting layer containing phosphors therein. Light emitted from the LED sequentially moves the light-incident face, the light-converting layer and the light-emergent face to leave the light-guiding board. The light-converting layer has a uniform thickness.

Description:
TECHNICAL FIELD  
       [0001]    The disclosure generally relates to a light emitting diode module. 
       DESCRIPTION OF RELATED ART  
       [0002]    As new type light source, LEDs are widely used in various applications. A conventional LED module includes a base, a pair of leads fixed in the base, a die mounted on the base and electrically connected to the leads and an encapsulant secured to the base and sealing the die. In order to produce white light, the die is made of a predetermined material to emit blue light, and large quantities of yellow phosphors spread on the encapsulant. The yellow phosphors absorb the blue light from the die and are excited thereby to produce yellow light. The yellow light mixes with the blue light to generate white light. 
         [0003]    However, the phosphors exposed are prone to be ruined by accident. 
         [0004]    Therefore, an LED module is desired to overcome the above described shortcomings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0005]    Many aspects of the disclosure can be better understood with reference to the following drawings. The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the disclosure. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views. 
           [0006]      FIG. 1  is a schematic view of an LED module in accordance with a first embodiment of the present disclosure. 
           [0007]      FIG. 2  is a schematic view of an LED module in accordance with a second embodiment of the present disclosure. 
           [0008]      FIG. 3  is a schematic view of an LED module in accordance with a third embodiment of the present disclosure. 
           [0009]      FIG. 4  is a schematic view of an LED module in accordance with a fourth embodiment of the present disclosure. 
           [0010]      FIG. 5  is a schematic view of an LED module in accordance with a fifth embodiment of the present disclosure. 
           [0011]      FIG. 6  is a schematic view of an LED module in accordance with a sixth embodiment of the present disclosure. 
       
    
    
     DETAILED DESCRIPTION 
       [0012]    Embodiments of an LED module will now be described in detail below and with reference to the drawings. 
         [0013]    Referring to  FIG. 1 , an LED module in accordance with a first embodiment comprises a light-guiding board  10 , two LEDs  20  arranged facing two opposite lateral sides of the light-guiding board  10 , respectively, and a light-reflecting board  30  facing a bottom of the light-guiding board  10 . The board  10  has a shape of a flat plate. 
         [0014]    The light-guiding board  10  may be made of epoxy silicone, polycarbonate, polymethylmethacrylate or other transparent materials. The light-guiding board  10  comprises two light-incident faces  11 , a light-emergent face  13 , a light-reflecting face  15  opposite to the light-emergent face  13 , and a light-converting layer  17 . The two light-incident faces  11  face the two LEDs  20  to receive the light emitted from the two LEDs  20 , respectively. The light-reflecting face  15  reflects the light moving through the two light-incident faces  11  and striking on the light-reflecting face  15  towards the light-emergent face  13 . The light-reflecting board  30  faces the light-reflecting face  15  to reflect some light passing through the light-reflecting face  15  towards the light-guiding board  10 . The light-reflecting board  30  is parallel to the light-reflecting face  15 . The light-converting layer  17  contains phosphors therein. The phosphors may be YAG phosphors, RGB phosphors, or RG phosphors. The phosphors in the light-converting layer  17  can be excited by the light from the LEDs  20  to emit light with a wave length different from that of the light generated by the LEDs  20 . A mixture of the lights with different wave lengths could obtain a light with a desired color such as white. The light-converting layer  17  is parallel to the light-emergent face  13 . In the first embodiment of this disclosure, the light-converting layer  17  is formed at a top side of the light guiding board  10 ; a top face of the light-converting layer  17  is the light-emergent face  13 . A thickness of the light-converting layer  17  is uniform. The light-emergent face  13  is parallel to the light-reflecting face  15 . 
         [0015]    Referring to  FIG. 2  also, an LED module in accordance with a second embodiment is shown. In this embodiment, differing from the first embodiment, the light-converting layer  17   a  is formed at a middle portion of the light-guiding board  10   a , and a top face of the light-converting layer  17   a  is below and spaced a distance from the light-emergent face  13   a.    
         [0016]    Referring to  FIG. 3 , an LED module according to a third embodiment comprises a light-guiding board  10   b , an LED  20   b  arranged facing a lateral side of the light-guiding board  10   b , and a light-reflecting board  30   b  facing a bottom of the light-guiding board  10   b.    
         [0017]    The light-guiding board  10   b  may be made of epoxy silicone, polycarbonate, polymethylmethacrylate or other transparent materials. The light-guiding board  10   b  comprises a light-incident face  11   b , a light-emergent face  13   b , a light-reflecting face  15   b  opposite to the light-emergent face  13   b , and a light-converting layer  17   b . The light-incident face  11   b  faces the LED  20   b  to receive the light emitted from the LED  20   b . The light-reflecting face  15   b  reflects the light moving through the light-incident face  11   b  and striking on the light-reflecting face  15   b  towards the light-emergent face  13   b . The light-reflecting board  30   b  faces the light-reflecting face  15   b  to reflect some light passing through the light-reflecting face  15   b  towards the light-guiding board  10   b . The light-reflecting board  30   b  is parallel to the light-reflecting face  15   b . The light-converting layer  17   b  contains phosphors therein. The phosphors may be YAG phosphors, RGB phosphors, or RG phosphors. The phosphors in the light-converting layer  17   b  can be excited by the light from the LED  20   b  to emit light with a wave length different from that of the light generated by the LED  20   b . A mixture of the lights with different wave lengths could obtain a light with a desired color such as white. The light-converting layer  17   b  is parallel to the light-emergent face  13   b . In the third embodiment of this disclosure, the light-converting layer  17   b  is formed at a top side of the light guiding board  10   b ; a top face of the light-converting layer  17   b  is the light-emergent face  13   b . A thickness of the light-converting layer  17   b  is uniform. The light-reflecting face  15   b  is sloping relative to the light-emergent face  13   b.    
         [0018]    Referring to  FIG. 4  also, an LED module in accordance with a forth embodiment is shown. In this embodiment, differing from the third embodiment, the light-converting layer  17   c  is formed at a middle portion of the light-guiding board  10   c,  and a top face of the light-converting layer  17   c  is below and spaced a distance from the light-emergent face  13   c.    
         [0019]    Referring to  FIG. 5 , an LED module according to a fifth embodiment comprises a light-guiding board  10   d , a plurality of LEDs  20   d  arranged facing a bottom of the light-guiding board  10   d , and a light-reflecting board  30   d  arranged below the LEDs  20   d.    
         [0020]    The light-guiding board  10   d  may be made of epoxy silicone, polycarbonate, polymethylmethacrylate or other transparent materials. The light-guiding board  10   d  comprises a light-incident face  11   d , a light-emergent face  13   d  opposite to the light-incident face  11   d , two opposite light-reflecting faces  15   d , and a light-converting layer  17   d.  The light-incident face  11   d  faces the LEDs  20   d  to receive the light emitted from the LEDs  20   d . In the fifth embodiment of this disclosure, a bottom face of the light-guiding board  10   d  is the light-incident face  11   d . The light-reflecting faces  15   d  reflect the light moving through the light-incident face  11   d  and striking on the light-reflecting faces  15   d  towards the light-emergent face  13   d . The LEDs  20   d  are located between the light-incident face  11   d  and the light-reflecting board  30   d . The light-reflecting board  30   d  is parallel to the light-incident face  11   d . The light-reflecting board  30   d  faces upwardly the LEDs  20   d  and the light-incident face  11   d  to reflect some light downwards from the LEDs  20   d  and the light-incident face  11   d  towards the light-incident face  11   d . The light-converting layer  17   d  contains phosphors therein. The phosphors may be YAG phosphors, RGB phosphors, or RG phosphors. The phosphors in the light-converting layer can be excited by the light from the LEDs  20   d  to emit light with a wave length different from that of the light generated by the LEDs  20   d . A mixture of the lights with different wave lengths could obtain a light with a desired color such as white. The light-converting layer  17   d  is parallel to the light-emergent face  13   d . In the fifth embodiment of this disclosure, the light-converting layer  17   d  is formed at a top side of the light guiding board  10   d ; a top face of the light-converting layer  17   d  is the light-emergent face  13   d . A thickness of the light-converting layer  17   d  is uniform. The light-emergent face  13   d  is parallel to the light-incident face  11   d.    
         [0021]    Referring to  FIG. 6  also, an LED module in accordance with a sixth embodiment is shown. In this embodiment, differing from the fifth embodiment, the light-converting layer  17   e  is formed at a middle portion of the light-guiding board  10   e,  and a top face of the light-converting layer  17   e  is below and spaced a distance from the light-emergent face  13   e.    
         [0022]    It is believed that the present embodiments and their advantages will be understood from the foregoing description, and it will be apparent that various changes may be made thereto without departing from the spirit and scope of the disclosure or sacrificing all of its material advantages, the examples hereinbefore described merely being preferred or exemplary embodiments of the disclosure.