Patent Publication Number: US-2010110393-A1

Title: Projector

Description:
BACKGROUND 
     1. Technical Field 
     The disclosure relates to projecting technology and, particularly, to a projector with effective heat dissipation. 
     2. Description of the Related Art 
     Development trends of projectors are towards improving image quality, brightness and compactness. However, the more compact a projector is, the more quickly it can get overheated. If a project is overheated, the performance and reliability of the projectors will suffer, together with deteriorated image quality and shortened service life span. Hence, heat dissipation in projectors is of great importance in projector design. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The FIGURE is a schematic view of a projector, according to an exemplary embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Referring to the FIGURE, a projector  100  according to an exemplary embodiment includes a casing  10 , inside of which are a projection lens module  20  with an optical axis OO′, an optical engine  30 , and a circuitry system  40 . The casing  10  includes a front wall  102 , a rear wall  104  opposite to the front wall  102 , a first sidewall  106 , and a second sidewall  108  opposite to the first sidewall  106 . The front wall  102 , the second sidewall  108 , the rear wall  104 , and the first sidewall  106  are connected in sequence. An aperture  102   a  is defined in the front wall  102  adjacent to the first sidewall  106 , corresponding to the projection lens module  20 . A front air inlet  102   b  is defined in the front wall  102  with a location different from that of the aperture  102   a . The first sidewall  106  defines a first air inlet  106   a  adjacent to the front wall  102 , and a second air inlet  106   b  adjacent to the rear wall  104 . The second sidewall  108  defines a first air outlet  108   a  and a second air outlet  108   b  substantially aligned with the first air inlet  106   a  and the second air inlet  106   b , respectively. 
     The projector  100  further includes a suction fan  12 , a first exhaust fan  14 , and a second exhaust fan  16 . The suction fan  12  is arranged corresponding to the front air inlet  102   b  for pulling air into the casing  10 . The first and second exhaust fans  14 ,  16  are arranged corresponding to the first and second air outlets  108   a ,  108   b , respectively. 
     The projection lens module  20  is substantially aligned with the aperture  102   a  of the front wall  102  and the optical axis OO′ of the projection lens module  20  is approximately perpendicular to the front wall  102 . The projection lens module  20  is positioned between the first air inlet  106   a  and the first air outlet  108   a.    
     The optical engine  30  includes a light-source module  32  and a light modulation module  34 . 
     The light-source module  32  is configured for generating light, and includes an L-shaped heat sink  321 , a red light source  322 , a green light source  323 , a blue light source  324 , a first dichroic mirror  325 , a second dichroic mirror  326 , and a condensing lens  328 . The heat sink  321  includes a first heat sink portion  321   a  approximately perpendicular to the front wall  102  and a second heat sink portion  321   b  approximately parallel to the front wall  102 . The red light source  322  is mounted on the first heat sink portion  321   a . The green light source  323  and the blue light source  324  are mounted on the second heat sink portion  321   b . The first dichroic mirror  325  and the second dichroic mirror  326  are positioned between the red light source  322  and the condensing lens  328 . Light emitted from the green light source  323  is reflected by the first dichroic mirror  325  towards the second dichroic mirror  326  and is propagated through the second dichroic mirror  326  towards the condensing lens  328 . Light emitted from the blue light source  324  is reflected by the second dichroic mirror  326  towards the condensing lens  328 . Light emitted from the red light source  322  is propagated through the first dichroic mirror  325  and the second dichroic mirror  326  towards the condensing lens  328 . The condensing lens  328  is configured for condensing the light from the red, green, and blue light source  322 ,  323 ,  324 . In this embodiment, the red light source  322 , the green light source  324  and the blue light source  326  are light emitting diodes (LED). 
     The light modulation module  34  is configured for modulating the light generated by the light-source module  32  to produce images towards the projection lens module  20  which focuses the images and projects the images onto a screen (not shown). The light modulation module  34  and the light-source module  32  are arranged between the second air inlet  106   b  and the second air outlet  108   b , and are arranged in order from the second air inlet  106   b  to the second air outlet  108   b . The projection lens module  20  is positioned adjacent to the light modulation module  34  of the optical engine  30 . 
     The circuitry system  40  is electrically connected to the optical engine  30 , and is configured for controlling the light-source module  32 , the light modulation module  34 , the suction fan  12 , the first exhaust fan  14 , and the second exhaust fan  16 . The circuitry system  40  is positioned between the projection lens module  20  and the second sidewall  108 , and substantially faces the front air inlet  102   b.    
     In the casing  10  of the projector  100 , when the suction fan  12 , the first exhaust fan  14 , and the second exhaust fan  16  are activated by the circuitry system  40 , air from the first air inlet  106   a  flows through the projection lens module  20  and the circuitry system  40  to take away heat generated by the projection lens module  20  and the circuitry system  40 , and is exhausted by the first exhaust fan  14  from the first air outlet  108   a  so that the projection lens module  20  and the circuitry system  40  are cooled. Air from the suction fan  12  flows through the circuitry system  40  to take away heat generated by the circuitry system  40  and is exhausted by the first exhaust fan  14  so that the circuitry system  40  is further cooled. Air from the second air inlet  106   b  flows through the light modulation module  34  and the light-source module  32  to take away heat generated by the light-source module  32  and the light modulation module  34  and is exhausted by the second exhaust fan  16  from the second air outlet  108   b  so that the light modulation module  34  and the light-source module  32  are cooled. In this way, heat generated in the casing  10  can be efficiently dissipated. 
     It is to be understood, however, that even though numerous characteristics and advantages of the present embodiments have been set fourth in the foregoing description, together with details of the structures and functions of the embodiments, the disclosure is illustrative only, and changes may be made in details, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.