Patent Publication Number: US-2010118280-A1

Title: Light-source module and projector having same

Description:
TECHNICAL FIELD 
     The present disclosure relates to projectors and, particularly, to a light-source module and a projector having the same with effective heat dissipation. 
     DESCRIPTION OF THE RELATED ART 
     Due to reduction of the size of projectors, the density of generated heat in projectors increases quickly. As a result, performance and reliability of the projectors will be influenced if heat dissipation is not effectively provided, and the service life span of the projectors may even be shortened. It is known that the light-source module is a main heat source in a projector, hence, how to discharge the heat generated from the light-source module effectively is a great challenge to designers in related fields. 
     What is needed, therefore, is a light-source module and a projector having the same with effective heat dissipation. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Many aspects of the present light-source module and projector can be better understood with reference to the accompanying drawings. The components in the drawing are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the present light-source module and projector. 
         FIG. 1  is a schematic, plan view of a projector according to a first exemplary embodiment. 
         FIG. 2  is a schematic, plan view of a projector according to a second exemplary embodiment. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Embodiments of the present disclosure will now be described in detail below, with reference to the accompanying drawings. 
     Referring to  FIG. 1 , a projector  1  according to a first exemplary embodiment is shown. The projector  1  includes a casing  10 , an optical engine  20 , a driving circuit board  30 , and a projection lens module  40 . 
     The casing  10  is configured for housing the optical engine  20 , the driving circuit board  30 , and the projection lens module  40 . The casing  10  includes a front wall  104 , a rear wall  102 , a first sidewall  101 , and a second sidewall  103  opposite to the first sidewall  101 . The first sidewall  101 , the front wall  104 , the second sidewall  103 , and the rear wall  102  are connected in sequence. In the present embodiment, the front wall  104  defines an aperture  104   a  adjacent to the second sidewall  103  and an air inlet  104   b  located beside the aperture  104   a  and adjacent the first sidewall  101 . The first sidewall  101  defines a first air outlet  101   a  adjacent the front wall  104 , and a second air outlet  101   b  adjacent the rear wall  102 . The second sidewall  103  defines a first air inlet  103   a  and a second air inlet  103   b  substantially aligned with the first air outlet  101   a  and the second air outlet  101   b  respectively. 
     In the present embodiment, a first exhaust fan  11  and a second exhaust fan  12  are arranged corresponding to the first air outlet  101   a  and the second air outlet  101   b  respectively. A first pulling fan  13  is arranged corresponding to the air inlet  104   b  for pulling air into the casing  10 . A blower  14  is secured on the rear wall  102  for blowing air coming into the casing  10  from the second air inlet  103   b  towards the second air outlet  101   b.    
     The projection lens module  40  is substantially aligned with the aperture  104   a  of the front wall  104  and located between the first air outlet  101   a  and the first air inlet  103   a.    
     The optical engine  20  includes a light-source module  21  and an image forming module  22 . The image forming module  22  is configured for producing images towards the projection lens module  40  which focusing the images and then projects the images onto a screen (not shown). The light-source module  21  is configured for providing light for the image forming module  22  to produce the images. The image forming module  22  and the light-source module  21  are arranged between the second air inlet  103   b  and the second air outlet  101   b  and are arranged in order from the second air inlet  103   b  to the second air outlet  101   b.  The projection lens module  40  is disposed adjacent to the image forming module  22  of the optical engine  20  and with its optical axis substantially perpendicular to the optical engine  20 . 
     The light-source module  21  includes a blue light source  211 , a green light source  212 , a red light source  213 , a first heat sink  214 , and a second heat sink  215 . The first heat sink  214  is attached to the green light source  212  for dissipating heat generated from the green light source  212 . The second heat sink  215  is attached to the blue light source  211  and the red light source  213  for dissipating heat generated from the blue light source  211  and the red light source  213 . The first heat sink  214  is separated from the second heat sink  215 . In the present embodiment, the blue light source  211 , the green light source  212 , and the red light source  213  are light emitting diodes (LEDs). The blue light source  211 , the green light source  212 , and the red light source  213  are arranged on a line substantially perpendicular to the first sidewall  101 . The light emitting directions of the blue light source  211 , the green light source  212 , and the red light source  213  are substantially parallel to each other, and face towards the front wall  104 . The air coming into the casing  10  from the second air inlet  103   b  can be blown towards the second air outlet  101   b  by the blower  14  passing through the first heat sink  214  and the second heat sink  215 . Therefore, the heat generated by the blue light source  211 , the green light source  212 , and the red light source  213  can be discharged efficiently. 
     The driving circuit board  30  is electrically connected to the light-source module  21  for driving the light-source module  21 . The driving circuit board  30  is disposed between the projection lens module  40  and the first sidewall  101 , and substantially aligned with the first air outlet  101   a.  The air coming into the casing  10  from the first air inlet  103   a  can pass through the projection lens module  40  and the driving circuit board  30  to dissipate heat from them and then exit the casing  10  from the first air outlet  101   a.  The air coming into the casing  10  from the air inlet  104   a  can pass through the driving circuit board  30  to dissipate heat thereof and then exit the casing  10  from the first air outlet  101   a.    
     It is known that, in a projector using LED light source, the power of the green light source  212  is usually much bigger than the power of the blue light source  211  and the power of the red light source  213 , therefore, the green light source  212  usually need a more efficient heat dissipating than other light source. In the present embodiment, the green light source  212  is attached to the first heat sink  214  which is separated from the second heat sink  215 , thus, the green light source  212  can obtain a more efficient heat dissipating than the blue light source  211  and the red light source  213 , accordingly, the light-source module  21  can have a efficient heat dissipating. 
     Referring to  FIG. 2 , a projector  2  according to a second exemplary embodiment is shown. The projector  2  is similar to the projector  1  of the first exemplary embodiment. The difference between the projector  2  and the projector  1  is that, in the projector  2  of the second exemplary embodiment, the blue light source  211 , the green light source  212 , and the red light source  213  are arranged to form a L-shaped structure. The light emitting direction of the green light source  212  is perpendicular to the light emitting direction of the blue light source  211  and the red light source  213 . 
     While certain embodiments have been described and exemplified above, various other embodiments will be apparent to those skilled in the art from the foregoing disclosure. The present invention is not limited to the particular embodiments described and exemplified, and the embodiments are capable of considerable variation and modification without departure from the scope of the appended claims.