Abstract:
An optical splitter for distributing a beam of light along a plurality of output paths. The amount of light output from each output path is user adjustable according to one embodiment of the present invention. In another embodiment the amount of light output from each output path is determined by the arrangement of the optical splitter. The present invention allows a single high-power high-intensity light generation source to simultaneously provide light to a plurality of lighting devices, instruments or tools.

Description:
FIELD OF INVENTION 
     The present invention generally relates to an optical splitter, and more particularly the present invention relates to an optical splitter for guiding a beam of light among a plurality of paths. 
     BACKGROUND OF THE INVENTION 
     High-power high-luminance light sources, such as a 300 Watt Xenon arc lamp light generator, are used in many important applications, including medical procedures. In this regard, the light source is used to generate light for illuminating a work area, such as a portion of a body involved in surgery. The light source typically supplies light to head gear worn on a surgeon&#39;s head. The light is focused onto the work area to aid the surgeon&#39;s vision. One drawback to these high-power, high-luminance light sources is that they are very costly. A typical arc lamp light generator can cost in the range of $3000-$4000. Accordingly, there is a need to obtain greater cost efficiencies from such devices, by allowing a single light source to simultaneously supply light to a plurality of tools or instruments. The present invention addresses these and other drawbacks of the prior art. 
     SUMMARY OF THE INVENTION 
     According to the present invention there is provided an optical splitter for distributing input light waves among one or more output light paths. 
     An advantage of the present invention is the provision of an optical splitter which allows the efficient distribution of light to be selectively varied among a plurality of light output paths. 
     Another advantage of the present invention is the provision of an optical splitter which includes a plurality of adapters for dividing and sub-dividing the distribution of light among a plurality of paths. 
     Still another advantage of the present invention is the provision of an optical splitter which varies the distribution of light among a plurality of paths by modifying the position of a light source relative to the plurality of paths. 
     Still another advantage of the present invention is the provision of an optical splitter which variably distributes light among a plurality of fixed light output paths. 
     Yet another advantage of the present invention is the provision of an optical splitter which distributes light among a plurality of paths by reflecting light from a light source. 
     Still other advantages of the invention will become apparent to those skilled in the art upon a reading and understanding of the following detailed description, accompanying drawings and appended claims. 
    
    
     BRIEF DESCRIPTION OF THE DRAWING 
     The invention may take physical form in certain parts and arrangements of parts, a preferred embodiment and method of which will be described in detail in this specification and illustrated in the accompanying drawings which form a part hereof, and wherein: 
     FIG. 1 is a front perspective view of an optical splitter according to a first embodiment of the present invention; 
     FIG. 2 is a perspective view of the selector of the optical splitter shown in FIG. 1; 
     FIG. 3 illustrates a  50 - 50  position of the optical splitter shown in FIG. 1; 
     FIG. 4 illustrates a  100 - 0  position of the optical splitter shown in FIG. 1; 
     FIG. 5 illustrates a  30 - 70  position of the optical splitter shown in FIG. 1; 
     FIG. 6A is a perspective view of an optical splitter according to a second embodiment of the present invention; 
     FIG. 6B illustrates alternative light distributor embodiments; 
     FIG. 7 is a perspective view of an optical splitter according to third and fourth embodiments of the present invention; 
     FIG. 8 is a perspective view of an optical splitter according to a fifth embodiment of the present invention; 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to the drawings wherein the showings are for the purpose of illustrating preferred embodiments of the invention only and not for the purpose of limiting same, FIG. 1 shows an optical splitter  20  according to a first embodiment of the present invention. Optical splitter  20  is generally comprised of a housing  30 , an input port  22 , an output port  24 , and a selector  40 . 
     Housing  30  is generally comprised of a front face  32 , a rear face  34 , side walls  36 , top wall  38  and a bottom wall. Housing  30  houses selector  40 , which is described in detail below. 
     Input port  22  and output port  24  are respectively used to receive light waves into splitter  20  and transmit light waves from splitter  20 . Input port  22  includes an input light distributor  26  for receiving light from an external light source, and carrying the light into housing  30 . It should be understood that the light source may take the form of a light generation means, (such as a Xenon arc lamp light generator), or another light distributor located “downstream.” Input light distributor  26  includes an input interface  23  for connecting input port  22  to the external light source. In a preferred embodiment, input interface  23  takes the form of a male connector. Output port  24  includes a plurality of output light distributors  28 A,  28 B for transmitting light exiting from splitter  20  to an instrument, tool, or another optical splitter. Output light distributors  28 A,  28 B include a respective output interface  25  for connecting output port  24  with a receiving light distributor. In a preferred embodiment, output interfaces  25  take the form of female connectors. It should be appreciated that output light distributors  28 A and  28 B are aligned adjacent to each other, and input light distributor  26  is located adjacent to output light distributors  28 A and  28 B (FIG.  2 ). Input light distributor  26 , and output light distributors  28 A,  28 B are optical conductors which propagate light via internal reflection or refraction, as will be readily understood by one of ordinary skill in the art. 
     Selector  40  will now be described with reference to FIG.  2 . Selector  40  varies the amount of light distributed by each of the output ports  24 , and includes dial  42  and arm  44 . Dial  42  protrudes from a side wall  36  of housing  30 , and provides a user interface for adjusting splitter  20 , as will be explained below. In a preferred embodiment, dial  42  takes the form of a generally circular disk, which is rotatable about its central axis A 1 . Arm  44  connects dial  42  with input port  22 , and more particularly input light distributor  26 . In this regard, arm  44  includes a first connector  46  for attaching arm  44  to dial  42 , and a second connector  48  for attaching arm  44  to input light distributor  26 . In a preferred embodiment, first connector  46  takes the form of a ring or eye, which is dimensioned to receive a protrusion  43  (e.g., a stud or pin) which protrudes from the surface of dial  42 . Second connector  48  also takes the form of a ring or eye, which is dimensioned to fit around input light distributor  26 . 
     As dial  42  is rotated about central axis A 1 , input light distributor  26  is moved laterally, in the direction of line L 1 . Consequently, input light distributor  26  is moved relative to output light distributors  28 A and  28 B, as will now be explained with reference to FIGS. 3-5. As indicated above, output light distributors  28 A and  28 B are aligned adjacent to each other. Accordingly, the light transmitted by input light distributor  26  in the vicinity of output light distributors  28 A and  281  will either be received by output light distributor  28 A or by output light distributor  28 B. As a result, the percentage of light distributed by each output light distributor  28 A,  28 B will vary depending upon the position of input light distributor  26  relative to output light distributors  28 A,  28 B. For instance, in the case where input light distributor  26  is centrally aligned (FIG.  3 ), output light distributors  28 A and  28 B will each distribute 50% of the light transmitted by input light distributor  26 . When input light distributor  26  is positioned as shown in FIG. 4, output light distributor  28 A will distribute 100% of the light transmitted by input light distributor  26 , while output light distributor  28 B will distribute 0% (no light). When input light distributor  26  is positioned as shown in FIG. 5, output light distributor  28 A will distribute 30% of the light transmitted by input light distributor  26 , while output light distributor  28 B will distribute 70%. Accordingly, as dial  42  is rotated the percentage of light distributed by each output light distributor is varied. In this respect, the amount of light distributed via each output light distributor will vary a predetermined amount in accordance with the external adjustment of selector  40 . 
     It should be appreciated that the form of selector  40  shown in FIG. 2-5 is provided solely for the purpose of illustrating a preferred embodiment of the present invention and not for limiting same. In this regard, selector  40  can take other suitable forms for modifying the position of the input light distributor relative to the output light distributors. For instance, selector  40  may take the form of a linear movement device (e.g., a linear slide), which moves the input light distributor relative to the output light distributor in a linear fashion. Moreover, it should be understood that while optical splitter  20  has been shown as having only two output ports for the purpose of illustrating a preferred embodiment of the present invention, optical splitter  20  may have more than two output ports to divide the light input to splitter  20  among three or more paths. 
     Turning now to FIG. 6A, there is shown a second embodiment of the present invention. Optical splitter  60  is generally comprised of a housing  90 , an input port  62 , output guide pipes  70  and a selector means (not shown). 
     Housing  90  houses input port  62 , output guide pipes  70 A,  70 B,  70 C and the selector means. Input port  62  and output guide pipes  70 A,  70 B and  70 C are respectively used to receive light into splitter  60  and transit light from splitter  60 . Input port  62  includes an input light distributor  64  for receiving light from an external light source (e.g., a Xenon arc lamp light generator) and carrying the light into housing  90 . Input light distributor  64  includes an input interface  63  for connecting input port  62  to the external light source. Input light distributor  64  terminates at an output interface  66 . 
     Each output guide pipe  70 A,  70 B and  70 C is comprised of a light distributor  74  having a single input interface  72  and one or more respective output paths  82 ,  84 A,  84 B,  86 A,  86 B and  86 C. The output paths terminate at output interfaces  76 . Each output path is capable of transmitting light to an instrument, tool, or another optical splitter. Light distributors  74  propagate light via internal reflection or refraction, as will be readily understood by one of ordinary skill in the art. 
     It should be appreciated that output guide pipes  70  distribute the light along one or more paths. In this regard, output guide pipe  70 A distributes 100% of the light received at input interface  72  to output path  82 . Output guide pipe  70 B distributes 50% of the light received at input interface  72  to output path  84 A and 50% to output path  84 B. Similarly, output guide pipe  70 C distributes 33⅓% of the light received at input interface  72  to output path  86 A, 33⅓% to output path  86 B, and 33⅓% to output path  86 C. Accordingly, in the case of an output guide pipe having N output paths, each output path will distribute 1/N of the total light received by the output guide pipe. In this embodiment, while the output guide pipes are selectable, the distribution of light provided by each output guide pipe is fixed. It should be understood that the distribution percentages noted herein take account for system losses. 
     The purpose of the selector means is to selectably align output interface  66  of input port  62  with one of the input interfaces  72 . Selector means (not shown) may take many suitable forms, including rotating means for rotational movement or sliding means for linear movement. The rotating means or sliding means move input port  62  relative to output guide pipes  70 , or vice versa. In the embodiment illustrated in FIG. 6A, selector means moves input port  62  relative to output guide pipes  70  along line L 2 . It should be noted that output interface  66  and input interfaces  72  will be arranged adjacent and flush to their respective surfaces when appropriately aligned. In a preferred embodiment 100% of the light transmitted from output interface  66  is received by input interface  72 . However, the percentage of light received by input interface  72  may be reduced by changing the alignment of output interface  66  relative to input interface  72 , such that some percentage of the light from output interface  66  is not transmitted to input interface  72 . 
     It should be appreciated that the number and type of output guide pipes shown in FIG. 6A are examples only. For instance, the output guide pipes may distribute light along more than three paths. Moreover, the light distributors may take a variety of suitable forms. In this regard, the light distributors may allow for variable adjustment of the light distribution among each output path. For instance, FIG. 6B illustrates examples of light distributors  74 A,  74 B and  74 C, which allow for variable adjustment of the light distribution among three output paths. (e.g., output paths  86 A,  86 B and  86 C of light distributor  70 C). The light is distributed among the output paths in a similar manner as discussed in connection with the embodiment shown in FIGS. 3-5. 
     Referring now to FIG. 7, there is shown a stackable optical splitter  100 , according to another embodiment of the present invention. Splitter  100  is generally comprised of an input port  112 , light distributors  110 A and  110 B, and respective output ports  114 A and  114 B. Input port  112  is dimensioned to accept output interface  104  of input light source  102 . In this regard, input port  112  is suitably coupled with output interface  104 . Furthermore, input port  112  is also dimensioned to suitably couple with other stackable splitters. The distribution of light to output ports  114 A and  114 B will vary depending upon the position of output interface  104  in input port  112 . Similar to the operation of splitter  20 , the light input to input port  112  will be divided between the pair of light distributors  110 A and  110 B. As previously noted, light distributors  110 A,  110 B propagate light via internal reflection or refraction, as will be readily understood by one of ordinary skill in the art. 
     A second splitter  100 ′, according to another embodiment of the present invention, is also shown. Splitter  100 ′ further splits the light exiting output port  114 B. Splitter  100 ′ interfaces with output port  114 B, as will be explained below. Splitter  100 ′ is generally comprised of light distributor  120 , input port  122  and output ports  124 A and  124 B. Light distributor  120  includes paths  126 A and  126 B, which respectively terminate at output ports  124 A and  124 B. 
     In this embodiment the distribution of light is fixed. In this regard, light entering input port  122  is distributed evenly between paths  126 A and  126 B. Accordingly, 50% of the light received at input port  122  will be output at output port  124 A, and 50% of the light received at input port  122  will be output at output port  124 B. 
     It should be appreciated that splitters  100  and  100 ′ can have more than two output ports, and can thus further divide the distribution of light. Moreover, it should also be understood that one or more splitters  100  and/or  100 ′ may be linked together to distribute light among a plurality of paths. 
     FIG. 8 shows a splitter  160  according to yet another embodiment of the present invention. In this embodiment, splitter  160  is generally comprised of an input port  164 , a light reflecting member M, a lens L, and output ports  172 A and  172 B. Input port  164  receives light from an input light source  162 . Light reflecting member M is a movable reflector, such as a mirror, or a beam splitter. In a preferred embodiment light reflecting member M is at a 45 degree angle to input port  164 . Moreover, an optional lens L is positioned in front of input port  164  to focus the light received therefrom. Output port  172 A receives light directly from lens L, or in the case where lens L is not present, directly from input port  164 . Output port  172 B receives reflected light, which is reflected by light reflecting member M to output port  172 B. Depending upon the position of light reflecting member M relative to the input beam of light, a variable amount of light will reach output port  172 B. For instance, if light reflecting member reflects 20% of the light from input port  164  to output port  172 B, then output port  172 A will distribute only 80% of the light from input port  164 . The input port and output ports propagate light via internal reflection or refraction, as will be readily understood by one of ordinary skill in the art. 
     It should be appreciated that the optical splitters shown in the Figures are provided solely for the purpose of illustrating preferred embodiments of the present invention. In this regard, the present invention may take many other suitable forms. For instance, a light source is suitably distributed or modified using various mechanical means, lenses, prisms, micro-mirrors, light filters, polarizers, beam splitters, light valves, LCD shutters, and diffraction gratings. In the case of a filter, the filter is suitably used to filter colors, infrared rays or ultra violet rays. 
     It should also be appreciated that the light distributors may be formed of molded plastic, fiber optic (plastic or glass), flexible or rigid polymer, glass, quartz, or other material suitable for transmitting light. 
     Moreover, the light distributors may not be round, but rather shaped to accommodate a particular application (e.g., square, hexagonal, wedge-shaped, etc.). In addition the light distributors may be shaped to mix light along their length to cause a uniform output at the end of the light distributor. Furthermore, the light distributors may have coatings or filters at their ends to provide desired properties, such as color effects, reflect or absorb heat, reflect or absorb specific frequencies of light, and the like. 
     The light source may take such forms as an LED, laser diode, laser, arc lamp, halogen lamp, incandescent lamp, fluorescent tube, or any other suitable light generating means. The light can also be generated by a remote light source and fed to the optical splitter via a light pipe or optical cable. 
     The invention has been described with reference to a preferred embodiment. Obviously, modifications and alterations will occur to others upon a reading and understanding of this specification. It is intended that all such modifications and alterations be included insofar as they come within the scope of the appended claims or the equivalents thereof.