Patent Publication Number: US-2009234195-A1

Title: Minimal incision surgical light source module with light-emitting diodes

Description:
BACKGROUND OF THE INVENTION 
     1. Technical Field 
     The present invention relates to a minimal incision surgical light source module with light-emitting diodes (LEDs), and more particularly, to a minimal incision surgical light source module with LEDs for enabling minimal incision surgical illumination. 
     2. Description of Related Art 
     A minimal incision surgical light source module, when used in combination with optic fibers, can directly detect lesions inside a patient&#39;s body in a least invasive way and transmit lesion images out of the body correctly and instantly. Among the several light sources generally used with minimal incision surgical endoscopes, LEDs have constantly improved performances and brightness and, as a cold light source, can be used for a prolonged period of time without generating high heat. Therefore, LEDs have been viewed as a new alternative minimal incision surgical light source that will take the place of halogen lamps. 
     However, as the length of optical fibers used with a minimal incision surgical endoscope increases, light rays transmitted within the optical fibers are subject to loss, so that light-emitting efficiency decreases as the length of the optical fibers increases. Consequently, light-emitting intensity at the ends of the optical fibers is insufficient for illumination. In order to provide sufficient brightness, a plurality of LEDs must be used. 
     When the number of LEDs in a light source module of a minimal incision surgical endoscope is increased, the light source module has a larger volume, which not only leads to a higher cost of the minimal incision surgical endoscope, but also limits the overall volume of the minimal incision surgical endoscope. Hence, if the illumination effect of a light source module of the minimal incision surgical endoscope can be enhanced without increasing the size of the light source module, the limitation on the application length of optical fibers can be relaxed. 
     For instance, U.S. Pat. No. 6,832,849 discloses a “light radiation device, light source device, light radiation unit, and light connection mechanism”, in which the light source device is configured to provide a light source in the form of a light beam and comprises a light-guiding member assembly and a casing. Therein, the light-guiding member assembly includes a plurality of bundled optical fibers or a glass rod and one or a plurality of LEDs, while the casing houses a first light source lens and a second light source lens. The first light source lens collimates light rays emitted from the LED or plurality of LEDs in the light-guiding member assembly into generally parallel light rays. The second light source lens condenses the light rays from the first light source lens and introduces the condensed light rays to the light-guiding member assembly. 
     According to the prior art cited above, two light source lenses are arranged in the light-emitting path of each LED, so as to condense the light rays emitted from all the LEDs onto an optical coupling surface of an optical fiber. However, when there are a plurality of LEDs in the light source module, the distance from each LED to the optical coupling surface of the optical fiber is different, but the same lens combination is used in the light-emitting path of each LED. Thus, light rays emitted from some of the LEDs may be used ineffectively, thereby lowering a light-emitting efficiency of the entire light source module. 
     BRIEF SUMMARY OF THE INVENTION 
     It is an objective of the present invention to provide a minimal incision surgical light source module with LEDs, wherein the LEDs are used as a minimal incision surgical light source and a fiber-optic connector is configured to couple the light source into an optical fiber. In addition, a lens set and a reflector set are provided for concentrating light rays emitted from each of the LEDs, so as to increase the efficiency with which the light rays are coupled into the optical fiber, thereby reducing the number of LEDs used. Therefore, sufficient illumination intensity can be achieved without increasing the volume of the minimal incision surgical light source module. 
     In order to increase a light source intensity for a minimal incision surgical endoscope, it is another objective of the present invention to provide a minimal incision surgical light source module with LEDs which comprises a fiber-optic connector and a light-emitting unit, both housed in a housing. The fiber-optic connector is configured to couple light rays emitted from the light-emitting unit into an optical fiber, so as to provide a minimal incision surgical light source. 
     It is still another objective of the present invention to provide a light-emitting unit for use with a minimal incision surgical light source module with LEDs, wherein the light-emitting unit comprises a thermally conductive base and at least one LED. Therein, the thermally conductive base can be designed with different inclination angles so that a light field generated by the at least one LED is concentratedly projected to the same area, thereby optimizing an LED light source intensity for a minimal incision surgical endoscope. Thus, by increasing the light source intensity for the minimal incision surgical endoscope, a clearer diagnostic image can be obtained. 
     To achieve these ends, the present invention provides a minimal incision surgical light source module with LEDs, comprising: at least two first LEDs; at least two first lens sets, each arranged in a light-emitting path of a corresponding said first LED for coupling light therefrom in a one-to-one manner; at least two reflector sets, each arranged in a light-emitting path of a corresponding said first lens set for coupling light therefrom in a one-to-one manner; a second lens set arranged in light-emitting paths of the reflector sets for coupling light therefrom; and a fiber-optic connector arranged in a light-emitting path of the second lens set for coupling light therefrom. 
     To achieve the aforementioned ends, the present invention further provides a minimal incision surgical light source module with an LED, comprising a third LED, a fourth lens set arranged in a light-emitting path of the third LED for coupling light therefrom, and a fiber-optic connector arranged in a light-emitting path of the fourth lens set for coupling light therefrom. 
     To achieve the aforementioned ends, the present invention also provides a minimal incision surgical light source module with an LED, comprising a fourth LED, a fifth lens attached to the fourth LED, and a fiber-optic connector arranged in a light-emitting path of the fifth lens for coupling light therefrom. 
     To achieve the aforementioned ends, the present invention further provides a minimal incision surgical light source module with an LED, comprising: a housing having a first side surface and a second side surface; a fiber-optic connector disposed on the first side surface and having an optical coupling surface; and a light-emitting unit disposed on an inner side of the second side surface and comprising a thermally conductive base and at least one LED, which is connected to the thermally conductive base in a thermally conductive manner and has a light field projecting to the optical coupling surface. 
     To achieve the aforementioned ends, the present invention also provides a light-emitting unit for use with a minimal incision surgical light source module with LEDs, wherein the light-emitting unit comprises a thermally conductive base and at least one LED, which is connected to the thermally conductive base in a thermally conductive manner and has a light field projecting to an optical coupling surface of a fiber-optic connector. 
     The present invention can be implemented to provide at least the following advantageous effects:
         1. The lens sets are arranged to condense the light rays emitted from the LEDs, thereby improving the light utilization efficiency of the LEDs;   2. As the light utilization efficiency of the LEDs is improved, the number of LEDs used can be reduced, thereby allowing the minimal incision surgical light source module to be miniaturized; and   3. As the lens sets condense the light rays emitted from the LEDs, light coupled into the optical fiber can have a low loss rate, thereby enhancing a light-emitting intensity of the minimal incision surgical light source.       

     A detailed description of further features and advantages of the present invention is given below, so that a person skilled in the art is allowed to understand and carry out the technical content of the present invention, and can readily comprehend the objectives and advantages of the present invention by reviewing the content disclosed herein, the appended claims and the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
       The invention as well as a preferred mode of use, further objectives and advantages thereof will be best understood by reference to the following detailed description of illustrative embodiments when read in conjunction with the accompanying drawings, wherein: 
         FIG. 1  is a perspective view of a minimal incision surgical light source module with LEDs according to a first embodiment of the present invention when assembled; 
         FIG. 2  is a cross-sectional view of the minimal incision surgical light source module with LEDs according to the first embodiment of the present invention; 
         FIG. 3  is an exploded perspective view showing another aspect of the minimal incision surgical light source module with LEDs according the first embodiment of the present invention; 
         FIG. 4  is a cross-sectional view showing yet another aspect of the minimal incision surgical light source module with LEDs according to the first embodiment of the present invention; 
         FIG. 5  is a cross-sectional view of a minimal incision surgical light source module with an LED according to a second embodiment of the present invention; 
         FIG. 6  shows a first embodiment of a lens set according to the present invention; 
         FIG. 7  shows a second embodiment of the lens set according to the present invention; 
         FIG. 8  shows a third embodiment of the lens set according to the present invention; 
         FIG. 9  shows a fourth embodiment of the lens set according to the present invention; 
         FIG. 10  shows a fifth embodiment of the lens set according to the present invention; 
         FIG. 11  is a cross-sectional view of a minimal incision surgical light source module according to a third embodiment of the present invention; 
         FIG. 12  a perspective view of a minimal incision surgical light source module according to a fourth embodiment of the present invention when assembled; 
         FIG. 13  is across-sectional view of the minimal incision surgical light source module according to the fourth embodiment of the present invention; 
         FIG. 14  is a cross-sectional view showing another aspect of the minimal incision surgical light source module according to the fourth embodiment of the present invention; 
         FIG. 15  is a perspective view of a light-emitting unit of the minimal incision surgical light source module according to the fourth embodiment of the present invention; 
         FIG. 16  is a cross-sectional view showing still another aspect of the minimal incision surgical light source module according to the fourth embodiment of the present invention; and 
         FIG. 17  is a perspective view showing another aspect of the light-emitting unit of the minimal incision surgical light source module according to the fourth embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     First Embodiment 
     As shown in  FIGS. 1 and 2 , a minimal incision surgical light source module  100  with LEDs according to this embodiment of the present invention comprises at least two first LEDs  121 , at least two first lens sets  130 , at least two reflector sets  140 , a second lens set  150 , and a fiber-optic connector  160 . 
     The first LEDs  121  serve as a light source of a minimal incision surgical endoscope, wherein each of the first LEDs  121  can be connected to a heat dissipation device  200  in a thermally conductive manner to facilitate heat dissipation from each of the first LEDs  121 . Alternatively, a plurality of LEDs  120  can be used as the light source and be configured so as to be replaceable, so that any one of the LEDs  120  can be conveniently replaced when damaged. 
     Each of the first lens sets  130  is arranged in a light-emitting path of a corresponding said first LED  121  for coupling light therefrom in a one-to-one manner. Light rays emitted from the first LEDs  121  have light-emitting paths passing through the first lens sets  130 . 
     Each of the reflector sets  140  is arranged in a light-emitting path of a corresponding said first lens set  130  for coupling light therefrom in a one-to-one manner. Each of the reflector sets  140  comprises a first reflector unit  141  and a second reflector unit  142 , wherein the first and second reflector units  141  and  142  are arranged relative to each other in a light-coupling configuration. 
     Light rays emitted from the first lens sets  130  fall on the first reflector units  141  and are reflected for the first time by the first reflector units  141 . As a result, light-emitting paths of the light rays have their directions changed. The light rays reflected by the first reflector units  141  are projected to the second reflector units  142 , which are arranged relative to the first reflector units  141  in a light-coupling configuration, and reflected for a second time by the second reflector units  142 , so that the directions of the light-emitting paths of the light rays are changed again. 
     The reflector sets  140  are provided to change the directions of light-emitting paths. Therefore, light rays coming from each of the first lens sets  130  can have the directions of their light-emitting paths changed by a corresponding said reflector set  140 , so that all the light-emitting paths are concentrated toward an axis  101  of the minimal incision surgical light source module  100 , thereby condensing the light again. 
     Referring to  FIG. 3 , in addition to being arranged in the light-emitting paths of the first lens sets  130  in a one-to-one light-coupling configuration, the first and second reflector units  141  and  142  may also be integrally formed as a first annular reflector  143  and a second annular reflector  144 , respectively, wherein the first annular reflector  143  is arranged concentrically with respective to and outside the second annular reflector  144 . 
     The first annular reflector  143  formed by the first reflector unit  141  is located at a first concentric circle  145  having a center defined by the axis  101  of the light source module, while the second annular reflector  144  formed by the second reflector unit  142  is located at a second concentric circle  146  and disposed relative to the first annular reflector  143  in such a way as to couple light therefrom. By substituting the integrally formed first and second annular reflectors  143  and  144  for the first and second reflector units  141  and  142  which are arranged relative to each other in a one-to-one configuration, assembly and production steps of the minimal incision surgical light source module  100  can be simplified. 
     The second lens set  150  is arranged in light-emitting paths of the reflector sets  140  for coupling light therefrom. A light beam projecting into the second lens set  150  along the light-emitting path of each of the reflector sets  140  also passes through the second lens set  150 . 
     The fiber-optic connector  160  is arranged in a light-emitting path of the second lens set  150  for coupling light therefrom, so that light rays emitted from the first LEDs  121  can be coupled into an optical fiber by the fiber-optic connector  160  after passing through the first lens sets  130 , the reflector sets  140 , the second lens set  150  and the fiber-optic connector  160 , thereby providing illumination for minimal incision surgery. 
     As shown in  FIG. 4 , the minimal incision surgical light source module  100  with LEDs may further comprise a third lens set  170 , which is arranged on an axis of the second lens set  150  and in a light-emitting path of a second LED  122 . The second LED  122  and the third lens set  170  are arranged sequentially along the axis of the second lens set  150 , so that the light-emitting path of the second LED  122  passes through the third lens set  170 . 
     Second Embodiment 
     As shown in  FIG. 5 , a minimal incision surgical light source module  100  with an LED according to this embodiment comprises a third LED  123 , a fourth lens set  180 , and a fiber-optic connector  160 . 
     The third LED  123  serves as a light source of a minimal incision surgical endoscope and can be connected to a heat dissipation device  200  in a thermally conductive manner to facilitate heat dissipation from the third LED  123 . 
     The fourth lens set  180  is arranged in a light-emitting path of the third LED  123  for coupling light therefrom. Light rays emitted from the third LED  123  have light-emitting paths passing through the fourth lens set  180 . 
     The fiber-optic connector  160  is arranged in a light-emitting path of the fourth lens set  180  for coupling light therefrom. The fiber-optic connector  160  allows the light rays emitted from the third LED  123  to be coupled into an optical fiber after the light rays pass through the fourth lens set  180  and the fiber-optic connector  160 , thereby providing illumination for minimal incision surgery. 
     The first lens sets  130 , the second lens set  150 , the third lens set  170  and the fourth lens set  180  in the first embodiment and the second embodiment can each comprise a plurality of convex lenses  131 , or at least one convex lens  131  and at least one concave lens  132  arranged in a particular way. 
     As shown in  FIGS. 6 ,  7  and  8 , the first lens sets  130 , the second lens set  150 , the third lens set  170  or the fourth lens set  180  can each comprise a plurality of, such as two, convex lenses  131  arranged in a particular way. The convex lenses  131 , owing to their light-converging effect, can condense light rays emitted from the light source module. When the light source module comprises a plurality of, such as two or three, LEDs  120 , light rays emitted from the plurality of LEDs  120  can pass through a corresponding said first lens set  130 , the second lens set  150 , the third lens set  170  or the fourth lens set  180 , each comprising the plurality of convex lenses  131 , and be condensed into a light beam. 
     Alternatively, as shown in  FIGS. 9 and 10 , the first lens sets  130 , the second lens set  150 , the third lens set  170  or the fourth lens set  180  can each comprise at least one convex lens  131  and at least one concave lens  132 , such as three convex lenses  131  and one concave lens  132 , arranged in a particular way. As the convex lenses  131  and the concave lens  132  can converge and diverge light, respectively, light rays emitted from each of the LEDs  120  in the light source module can pass through a corresponding said first lens set  130 , the second lens set  150 , the third lens set  170  or the fourth lens set  180 , each comprising the at least one concave lens  132  and the at least one convex lenses  131 , and be condensed into a light beam. 
     Therefore, by virtue of the plurality of convex lenses  131 , or the at least one convex lens  131  and at least one concave lens  132 , in the first lens sets  130 , the second lens set  150 , the third lens set  170  or the fourth lens set  180 , the light rays emitted from each of the LEDs  120  will be condensed so as to provide a light-converging/condensing effect. Thus, the light rays become more concentrated, thereby enhancing the light-emitting intensity of the minimal incision surgical light source module  100 . 
     Third Embodiment 
     As shown in  FIG. 11 , a minimal incision surgical light source module  100  with an LED according to this embodiment comprises a fourth LED  124 , a fifth lens  190 , and a fiber-optic connector  160 . 
     The fourth LED  124  serves a light source of a minimal incision surgical endoscope and can be connected with a heat dissipation device  200  in a thermally conductive manner to facilitate heat dissipation from the fourth LED  124 . 
     The fifth lens  190  is attached to the fourth LED  124 . More particularly, the fifth lens  190  is fixedly attached to a light-emitting surface of the fourth LED  124  by an optical glue. The fifth lens  190  can be a convex lens  131 , so that, through a light-converging effect of the convex lens  131 , light rays emitted from the fourth LED  124  can be projected concentratedly to an optical coupling surface of the fiber-optic connector  160 . 
     The fiber-optic connector  160  is arranged in a light-emitting path of the fifth lens  190  for coupling light therefrom. With the fiber-optic connector  160 , the light rays emitted from the fourth LED  124  and passing through the fifth lens  190  and the fiber-optic connector  160  can be coupled into an optical fiber and serve as an illumination light source for minimal incision surgery. 
     Fourth Embodiment 
     Referring to  FIG. 12 , a minimal incision surgical light source module  100  according to this embodiment comprises a housing  220 , a fiber-optic connector  160  and a light-emitting unit  230 . 
     As shown in  FIG. 13 , the housing  220  has a first side surface  221  and a second side surface  222 , wherein the first side surface  221  is used to secure the fiber-optic connector  160  and protect an inner structure of the minimal incision surgical light source module  100 , while the second side surface  222  is located opposite the first side surface  221  for securing the light-emitting unit  230 . 
     The fiber-optic connector  160  is disposed on the first side surface  221  for connecting with an optical fiber. In addition, the fiber-optic connector  160  has an optical coupling surface  161  for coupling light rays emitted from the light-emitting unit  230  to the fiber-optic connector  160 , so as to provide illumination for minimal incision surgery. A vertical distance between the optical coupling surface  161  and the second side surface  222  is defined as a first distance  250 , which can be changed to adjust a projection distance between the light-emitting unit  230  and the optical coupling surface  161 . 
     The light-emitting unit  230  is disposed on an inner side of the second side surface  222  of the housing  220  and comprises a thermally conductive base  231  and at least one LED  120 . The thermally conductive base  231  is disposed on the inner side of the second side surface  222  and can have a level surface  240  and at least one pair of symmetric inclined surfaces  241  for securing the LED  120  and facilitating thermal conduction from the LED  120 . When the thermally conductive base  231  has one said pair of symmetric inclined surfaces  241 , each having an inclination angle δ, the inclination angles δ can be designed to control a projection direction of the LED  120 . The thermally conductive base  231  can be further connected with a heat dissipation device  200  in a thermally conductive manner to facilitate heat dissipation from the LED  120 . 
     The LED  120  is connected to the thermally conductive base  231  in a thermally conductive manner and has a light field projecting to the optical coupling surface  161 . When more than one said LED  120  is used as the light source, the inclination angles δ of the thermally conductive base  231  can be changed to adjust an overall projection light field of the LEDs  120 . As the LEDs  120  may have different beam angles, when the inclination angles δ of the thermally conductive base  231  are changed, it is preferable to select the LEDs  120  having the most appropriate beam angles based on the inclination angles δ, so that the light field of each said LED  120  is projected to the optical coupling surface  161 , thereby increasing a minimal incision surgical light source intensity. 
     In addition, the light-emitting unit  230  of the minimal incision surgical light source module  100  can also comprise a plurality of LEDs  120  arranged in different ways to match different said inclination angles δ, so that the light fields of the LEDs  120  are concentratedly projected to the optical coupling surface  161 , thereby increasing the minimal incision surgical light source intensity. More aspects of the aforementioned minimal incision surgical light source module  100  are described as follows. 
       FIG. 14  is a cross-sectional view showing a second aspect of the minimal incision surgical light source module  100  according to the fourth embodiment of the present invention, wherein the thermally conductive base  231  has a level surface  240  and a pair of symmetric inclined surfaces  241 , while the at least one LED  120  comprises a fifth LED  125 , a sixth LED  126  and a seventh LED  127 . The fifth LED  125  is connected to the level surface  240  in a thermally conductive manner while the sixth and the seventh LEDs  126  and  127  are connected respectively to the symmetric inclined surfaces  241  in the thermally conductive manner. 
     The fifth LED  125  has a first beam angle θ 1 , the sixth LED  126  has a second beam angle θ 2  and the seventh LED  127  has a third beam angle θ 3 . By designing the first, the second and the third beam angles θ 1 , θ 2  and θ 3  of the fifth, the sixth and the seventh LEDs  125 ,  126  and  127  to match the inclination angles δ of the thermally conductive base  231 , the light source of the light-emitting unit  230  can be more concentratedly projected to the optical coupling surface  161 , thereby enhancing the minimal incision surgical light source intensity. 
     Moreover, the fiber-optic connector  160  can be further provided with an optical lens set  162 , which can be any one of the lens sets  130 ,  150 ,  170  and  180  in the first, the second and the third embodiments. The optical lens set  162  can receive the light rays emitted from the light-emitting unit  230  and change refraction angles of the incident light rays so that the light rays are condensed and more concentrated. Thus, a utilization rate of light can be enhanced when the light rays are coupled into an optical fiber because the light rays are less likely to leak therefrom. 
     For example, the inclination angles δ of the thermally conductive base  231  can be designed at 20°, the first distance  250  can be adjusted to 2 cm, while the first, the second and the third beam angles θ 1 , θ 2  and θ 3  are all set at 60°, so that the light rays emitted from the light-emitting unit  230  are projected to the optical coupling surface  161  more concentratedly. 
     As shown in  FIG. 15 , the thermally conductive base  231  can also have a level surface  240  and two pairs of symmetric inclined surfaces  241  while the at least one LED  120  comprises a fifth LED  125  connected to the level surface  240  in a thermally conductive manner; and a sixth LED  126 , a seventh LED  127 , an eighth LED  128  and a ninth LED  129  connected respectively to the symmetric inclined surfaces  241  in the thermally conductive manner. 
     The fifth to the ninth LEDs  125  to  129  have a first to a fifth beam angles θ 1  to θ 5 , respectively. By properly arranging the plurality of LEDs  120  and matching the beam angles thereof with the inclination angles δ of the thermally conductive base  231 , the light fields of the LEDs  120  can be more concentrated, thereby enhancing the overall light source intensity of the light-emitting unit  230 , so that an increased minimal incision surgical light source intensity can be achieved. 
       FIG. 16  illustrates a third aspect of the minimal incision surgical light source module  100  according to the fourth embodiment of the present invention, wherein the thermally conductive base  231  is not provided with the level surface  240  shown in  FIG. 14  while the at least one LED  120  in the light-emitting unit  230  comprises the fifth LED  125  and the sixth LED  126 , which are connected respectively to the symmetric inclined surfaces  241  of the thermally conductive base  231  in a thermally conductive manner. By matching the first and the second beam angles θ 1  and θ 2  of the fifth LED  125  and the sixth LED  126  with the inclination angles δ of the thermally conductive base  231 , the light rays emitted from the light-emitting unit  230  can be projected to the optical coupling surface  161  more concentratedly before the light rays are coupled into the optical fiber by the fiber-optic connector  160 , so that the minimal incision surgical light source intensity is increased. 
       FIG. 17  illustrates a second aspect of the light-emitting unit  230  of the minimal incision surgical light source module  100  according to the fourth embodiment of the present invention, wherein the thermally conductive base  231  is not provided with the level surface  240  in  FIG. 15  while the at least one LED  120  comprises the fifth LED  125 , the sixth LED  126 , the seventh LED  127  and the eighth LED  128 , which are connected respectively to the symmetric inclined surfaces  241  of the thermally conductive base  231  in a thermally conductive manner. By adjusting an arrangement of the LEDs  120  and designing the inclination angles δ of the thermally conductive base  231  to match the beam angles of the plurality of LEDs  120 , the light rays emitted from the LEDs  120  can be more concentrated so as to increase the minimal incision surgical light source intensity. 
     The present invention has been described with preferred embodiments thereof, which are intended to demonstrate features of the present invention so that a person skilled in the art can readily understand and carry out the content disclosed herein, but are not intended to limit the scope of the present invention. Therefore, all equivalent changes or modifications made to the embodiments without departing from the spirit of the present invention should be encompassed by the appended claims.