Abstract:
An illuminated medical system comprises a medical instrument and a light transmitting waveguide. The waveguide projects lights from a distal portion of the waveguide toward a target area. The waveguide is formed primarily of a cyclic olefin copolymer or a cyclic olefin polymer.

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
       [0001]    This application is a continuation-in-part of U.S. patent application Ser. No. 12/191,164 (Attorney Docket No. 028638-001300US), filed Aug. 13, 2008, the entire contents of which are incorporated herein by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The inventions described below relate generally to the field of in vivo surgical field illumination during medical and surgical procedures. 
         [0004]    2. Background of the Invention 
         [0005]    Illumination of body cavities for diagnosis and or therapy has been limited by overhead illumination. High intensity incandescent lighting has been developed and has received limited acceptance as well as semiconductor and laser lighting, however these light sources have a heat and weight penalty associated with their use. Excessive heat can cause unwanted coagulation of blood, as well as unnecessarily heating of a patient&#39;s body. Additionally, heat buildup can cause various components fabricated from some polymers to exceed their glass transition temperature and deform. Heat buildup may also cause optical properties of various components to be compromised. Weight of some illumination systems makes them uncomfortable for an operator, especially during a lengthy procedure. Conventional light sources rely on fiber optic and similar waveguide materials to conduct light to a body cavity. Conventional waveguide materials that are suggested for medical use suffer from some of the unstable transmission characteristics under extended use described above, and their transmission characteristics may also change when sterilized using conventional techniques (e.g. autoclave, EtO, gamma or e-beam irradiation). Additionally, precision optical polymers have limited mechanical properties which limits their application in medical/surgical situations. 
         [0006]    Examples of conventional polymers that have traditionally been used with some success in surgical illumination systems include acrylics such as polymethylmethacrylate (PMMA) and polycarbonates (PC) such as Lexan®. Polycarbonate is desirable since it may be fabricated into various configurations which may be slightly bent without shattering. While polycarbonate has good mechanical strength and manufacturability, its optical properties are not optimal. For example, polycarbonate has a low light transmission efficiency, and therefore is not ideal for transmitting light, especially along a long pathway. Acrylic has also been used with some success in surgical illumination systems. It is more efficient at transmitting light than polycarbonate, is easy to process (e.g. may be injection molded), but acrylic is also brittle and can shatter. Also, acrylic has a relatively low glass transition temperature, and thus acrylic components do not tolerate heat buildup well, especially in medical illumination systems where heat is generated during use. Acrylic also absorbs moisture and this changes the refractive index of the material which can alter its performance. Therefore, it would be desirable to provide a material that is better suited for medical illumination systems and that has at least some of the desirable mechanical and optical properties of acrylic or polycarbonate while minimizing the less desired properties. For example, such materials would preferably have equivalent or better light transmission efficiency than acrylic, a higher glass transition temperature relative to acrylic, be easy to process like acrylic or polycarbonate, have better resistance to moisture absorption than acrylic, and be bendable without shattering like polycarbonate. Moreover, the material used must also be able to withstand terminal sterilization without compromising optical properties. Many polymers discolor when irradiated or can deform due to exposure to heat during sterilization. It would therefore also be advantageous to provide a material that can be terminally sterilized without damage. Also, any materials used in a medical application must also be biocompatible. At least some of these challenges will be addressed by the exemplary embodiments disclosed below. 
       BRIEF SUMMARY OF THE INVENTION 
       [0007]    The devices described below provide for surgical retraction or illumination, or both, with devices made primarily of an amorphous polyolefin, cyclo olefin copolymer (COC) or cyclo olefin polymer (COP). While many of the embodiments described below preferably use COP, one of skill in the art will appreciate that COC may also be used. 
         [0008]    Preferably, a retractor formed primarily of cyclo olefin polymer is used as the illumination device. A surgical illumination system formed of cyclo olefin polymer may include a generally cylindrical light waveguide having a bore sized to accommodate one or more surgical instruments, an illumination source, an illumination conduit for conducting illumination energy from the illumination source, and an adapter ring for engaging the illumination conduit and coupling illumination energy from the illumination conduit to the light waveguide. The adapter ring may permit relative movement between the illumination conduit and the light waveguide. 
         [0009]    The new illumination system may also include an illumination source, a generally cylindrical light waveguide formed of cyclo olefin polymer having a distal end and a proximal end, and a bore sized to accommodate one or more instruments or tools extending from the proximal end through the distal end. The waveguide conducts light from the proximal end to the distal end and projects the light from the distal end. The illumination conduit conducts light from the light source to the proximal end of the light waveguide. 
         [0010]    A COP illumination system may also include any suitable retractor system such as McCulloch retractor, and includes a channel in the retractor blade to accommodate a COP illuminator. In this system, the COP illuminator is also formed to have an air gap surrounding any active portion of the illuminator from the light input to the light output portion. The illuminator has active portions in which light passes and inactive or dead zones in which light does not pass as a result of the configuration and orientation of the input, output and surfaces of the illuminator. The dead zones may include elements to allow the illuminator to securely engage the retractor. 
         [0011]    The medical retractor system as described below includes a cannula, retractor or retractor blade having a cyclo olefin polymer element extending from the proximal end thereof to the distal end thereof, a light source operably coupled to the proximal end of the cyclo olefin polymer element, and at least one light extracting element near the distal end of the cyclo olefin polymer element. 
         [0012]    A COP blade insert illumination system includes one or more illumination elements composed of cyclo olefin polymer. The COP illumination elements operate as a waveguide and may incorporate optical components such as, for example, symmetric or asymmetric facets, lenses, gratings, prisms and or diffusers to operate as precision optics for customized delivery of the light energy. The illumination elements may be modular, allowing components to be mixed and matched for different sizes of blade retractors, or may be a single integrated unit. Each module may also have different performance characteristics such as a diffuse light output or a focused light output allowing users to mix and match optical performance as well. 
         [0013]    Any dissecting tools and/or retractors for small surgical sites such as the hand or foot may be formed of COP with a light input at the proximal end to enable the distal end to illuminate the surgical site. One or more structural elements such as wire may be co-molded into a COP tool for increased mechanical strength. A suitable COP compound is produced by Zeon Chemicals L.P. under the trademark Zeonor® and Zeonex®. These two polymers have at least some of the mechanical characteristics and at least some of the optical stability and characteristics for use in an illuminated medical system. 
         [0014]    In one aspect of the present invention, an illuminated medical system comprises a medical instrument and a light transmitting waveguide. The waveguide has a proximal region and a distal region, and is coupled to the medical instrument. The waveguide is configured to conduct light from the proximal region to the distal region thereof, and the waveguide projects the light from an extraction area preferably near the distal portion of the waveguide toward a target area. The waveguide is formed primarily of a cyclic olefin copolymer or a cyclic olefin polymer. 
         [0015]    The medical instrument may comprise one of a surgical retractor, a laryngoscope, a speculum, or an anoscope. Other medical instruments are also contemplated for use. The waveguide may be adjustably positionable relative to the medical instrument thereby allowing adjustment of the projected light onto the target area. The waveguide may further comprise one or more output optical structures disposed adjacent the distal portion thereof. The output optical structures may be configured to direct the light from the distal portion of the waveguide to the target area as well as the surface of the waveguide. The output optical structures may comprise one or more facets. The waveguide may comprise a tubular body, an elongate blade, or a half tubular body. The system may further comprise an illumination source, an illumination conduit, and an optical coupling. The illumination source may provide the light. The illumination conduit may be optically coupled with the illumination source and the waveguide. The illumination conduct may be configured to conduct light from the illumination source to the waveguide. The optical coupling may be coupled to the waveguide and the illumination conduit. The optical coupling may be configured to optically couple the illumination conduit with the waveguide so that the light may pass therebetween. The optical coupling also may be used to releasably hold the illumination conduit and the waveguide together. 
         [0016]    In still another aspect of the present invention, an illuminated medical system comprises a medical instrument and a light transmitting illuminator. The illuminator has a proximal region and a distal region, and is coupled to the medical instrument. The illuminator is configured to conduct light from the proximal region to the distal region thereof, and the illuminator comprises a light input portion, a light conducting portion, and a light output portion. The light output portion projects the light from the distal portion of the illuminator towards a target area, and the light conducting portion is formed primarily of a cyclic olefin copolymer or a cyclic olefin polymer. 
         [0017]    The light output portion may be adjustably positionable relative to the medical instrument thereby allowing adjustment of the projected light onto the target area. The light output portion may comprise one or more output optical structures disposed adjacent the distal end thereof. The output optical structures may be configured to direct the light from the light output portion to the target area. The output optical structures may comprise one or more facets. The light conducting portion may comprise a tubular body, an elongate blade, or a half tubular body. The system may further comprise an illumination source that provides the light, and an illumination conduit. The illumination conduit may be optically coupled with the light input portion and the illumination source, and the conduit may be configured to conduct light from the illumination source to the light input portion. An index matching material such as a liquid or gel may be used to help optically couple the components together. 
         [0018]    In yet another aspect of the present invention, a method for illuminating a medical work space comprises providing a medical instrument coupled to a light transmitting waveguide, and advancing the medical instrument and the waveguide toward the work space. The method also comprises illuminating the work space with light from the waveguide. The light passes from a proximal portion of the waveguide to a distal portion of the waveguide. The waveguide is formed primarily of a cyclic olefin copolymer or a cyclic olefin polymer. 
         [0019]    The medical instrument may comprise one of a surgical retractor, a laryngoscope, a speculum, or an anoscope. Advancing the medical instrument and the waveguide may further comprise positioning the medical instrument in a patient and retracting tissue with the medical instrument. Advancing the medical instrument and the waveguide may comprise positioning the medical instrument and the waveguide in a body orifice or into an incision. The waveguide may comprise a tubular body having a central channel, and advancing the medical instrument may comprise positioning the medical instrument through the central channel. Illuminating may comprise adjusting the waveguide position relative to the medical instrument, thereby adjusting illumination of the work space. Illuminating may comprise optically coupling the waveguide with an illumination source. 
         [0020]    In any of the embodiments disclosed herein, the waveguide or the light conducting portion of the illuminator may have a specific gravity less than that of polycarbonate or acrylic. The water absorption rate of the waveguide or the light conducting portion of the illuminator may be less than that of polycarbonate or acrylic. Therefore, the water absorption rate is preferably less than 0.01%. The light transmission efficiency of the waveguide or light conducting portion of the illuminator may be greater than that of polycarbonate or greater than or equal to that of acrylic. Thus, the light transmission efficiency is preferably greater than 90% and more preferably greater than 92%. The waveguide or the light conducting portion of the illuminator may have a refractive index greater than acrylic, and the glass transition temperature thereof may be greater than that of polycarbonate or acrylic. Thus, the refractive index is preferably greater than 1.49, and the glass transition temperature is greater than or equal to 105° C. The waveguide or illuminator is preferably biocompatible. 
         [0021]    These and other embodiments are described in further detail in the following description related to the appended drawing figures. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0022]      FIG. 1  is a perspective view of a COP blade insert illuminator. 
           [0023]      FIG. 1A  is a cross-section of the COP blade insert illuminator of  FIG. 1  taken along A-A. 
           [0024]      FIG. 1B  is a cross-section of the COP blade insert illuminator of  FIG. 1  taken along B-B. 
           [0025]      FIG. 2  is a perspective view of an alternate COP blade insert illuminator. 
           [0026]      FIG. 2A  is a perspective view of the attachment mechanism of the COP blade illuminator of  FIG. 2 . 
           [0027]      FIG. 3  is a perspective view of another COP blade insert illuminator. 
           [0028]      FIG. 3A  is a close perspective view of the light output section of the COP blade illuminator of  FIG. 3 . 
           [0029]      FIG. 3B  is a close perspective view of a conduit section of the COP blade illuminator of  FIG. 3 . 
           [0030]      FIG. 3C  is a front view of a light ray path for a light conduit section of the COP blade illuminator of  FIG. 3 . 
           [0031]      FIG. 4  is a perspective view of a single waveguide COP blade illuminator with a flexible input coupling for a short blade retractor. 
           [0032]      FIG. 5  is a perspective view of a single waveguide COP blade illuminator system with a flexible input coupling for a long blade retractor. 
           [0033]      FIG. 5A  is a perspective view of an alternate waveguide COP blade illuminator with a rigid input coupling. 
           [0034]      FIG. 6  is a perspective view of an alternate attachment mechanism for COP blade insert illuminator sections. 
           [0035]      FIG. 7  is a side view of a COP blade insert illuminator with stepped waveguide sections. 
           [0036]      FIG. 8  is a perspective view of an alternate single waveguide COP blade insert illumination system. 
           [0037]      FIG. 9  is a perspective view of a single waveguide COP blade insert with a light directing structure. 
           [0038]      FIG. 10  is a perspective view of a single waveguide COP blade insert with a light directing structure with an attachment mechanism. 
           [0039]      FIG. 11  is a perspective view of a single waveguide COP blade insert with a waveguide element co-molded with a retracting element. 
           [0040]      FIG. 12  is a perspective view of a COP illuminated retractor. 
           [0041]      FIG. 12A  is an exploded view of the input collar and the illumination blade input. 
           [0042]      FIG. 13  is a cross-section view of the COP illuminated retractor of  FIG. 12 . 
           [0043]      FIG. 14  is a side view of the COP illumination blade of  FIG. 12 . 
           [0044]      FIG. 15  is a front view of the COP illumination blade of  FIG. 12 . 
           [0045]      FIG. 16  is a side view of a COP laryngoscope cavity illuminator in use. 
           [0046]      FIG. 17  is a side view of a COP laryngoscope illumination system with an illumination source in the blade. 
           [0047]      FIG. 18  is a side view of a COP laryngoscope illumination system with an illumination source in the handle. 
           [0048]      FIG. 19  is a side view of an alternate COP laryngoscope illuminator according to the present disclosure. 
           [0049]      FIG. 20  is a side view of a metal blade laryngoscope including a COP illuminator waveguide engaging the blade. 
           [0050]      FIG. 21  is a cross section of the laryngoscope with COP illuminator waveguide of  FIG. 20  taken along B-B. 
           [0051]      FIG. 22  is a side view of a COP laryngoscope cavity illuminator waveguide. 
           [0052]      FIG. 23  is a side view of a COP speculum illumination system. 
           [0053]      FIG. 24  is a side view of the COP cavity illumination system of  FIG. 23  with the handles closed. 
           [0054]      FIG. 25  is a side view of an alternate COP cavity illumination system with the illumination source in the handle. 
           [0055]      FIG. 26  is a side view of another alternate COP cavity illumination system. 
           [0056]      FIG. 26A  is a cutaway view of the COP blade of cavity illumination system of  FIG. 26  taken along C-C. 
           [0057]      FIG. 26B  is a cutaway view of an alternate COP blade of cavity illumination system of  FIG. 26  taken along C-C. 
           [0058]      FIG. 27  is a side view of still another alternate COP cavity illumination system. 
           [0059]      FIG. 28  is a top view of yet another COP cavity illumination system according to the present disclosure. 
           [0060]      FIG. 29  is a cutaway view of the COP cavity illumination system of  FIG. 28  taken along D-D. 
           [0061]      FIG. 30  is a perspective view of a COP optical waveguide with a curved input light coupling. 
           [0062]      FIG. 31  is an enlarged perspective view of the distal end of the COP optical waveguide of  FIG. 30 . 
           [0063]      FIG. 32  is a perspective view of a COP optical waveguide with a split input coupling. 
           [0064]      FIG. 33  is cutaway view of the COP optical waveguide of  FIG. 32 . 
           [0065]      FIG. 34  is a cross-section of the COP optical waveguide of  FIG. 32  taken along B-B. 
           [0066]      FIG. 35  is a perspective view of an alternate COP optical waveguide with a split input coupling. 
           [0067]      FIG. 36  is a perspective view of another alternate COP optical waveguide with a split input coupling. 
           [0068]      FIG. 37  is a cross section of the distal end of a COP optical waveguide. 
           [0069]      FIG. 38  is a cross-section of the distal end of an alternate COP optical waveguide. 
           [0070]      FIG. 39  is a perspective view of an alternate COP optical waveguide with a reinforced and shielded split input coupling. 
           [0071]      FIG. 40  is a cutaway view of the COP optical waveguide of  FIG. 39 . 
           [0072]      FIG. 41  is a perspective view of the COP optical waveguide of  FIG. 39  with the clamp assembly removed for clarity. 
           [0073]      FIG. 42  is a side view of the COP optical waveguide of  FIG. 41 . 
           [0074]      FIG. 43  is a cutaway perspective view of a COP optical waveguide with the clamp assembly removed for clarity. 
           [0075]      FIG. 44  is a close up front view of the input connector of  FIG. 43 . 
           [0076]      FIG. 45  is a perspective view of a separable COP waveguide. 
           [0077]      FIG. 46  is a cutaway view of the COP optical waveguide of  FIG. 45 . 
           [0078]      FIG. 47  is a cutaway view of a COP optical waveguide with an extended reflecting surface. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0079]    Cyclic olefin copolymer (COC) and cyclic olefin polymer (COP) are a relatively new class of optical polymers that have glass-like clarity, and therefore are promising materials for optical components used in illuminated medical systems. COC is an amorphous polymer produced by chain copolymerization of cyclic monomers such as 8,9,10-trinorborn-2-ene (norbornene) or 1,2,3,4,4a,5,8,8a-octahydro-1,4:5,8-dimethanonaphthalene (tetracyclododecene) with ethane, TOPAS Advanced Polymer&#39;s TOPAS, Mitsui Chemical&#39;s APEL, or by ring-opening metathesis polymerization of various cyclic monomers followed by hydrogenation (e.g. Japan Synthetic Rubber&#39;s ARTON, Zeon Chemical&#39;s Zeonex and Zeonor). These later materials using a single type of monomer are more properly referred to as cyclic olefin polymers (COP). 
         [0080]    COC and COP have transparency similar to glass in its natural form. Therefore they may be used in optical components such as a waveguide, illuminator, or any of the components in the illuminated medical system, instead of acrylic or polycarbonate. COC and COP also have a high moisture barrier for a clear polymer and a low absorption rate. They are recognized to be a high purity product with low extractables and are halogen free. While material properties will vary due to monomer content, glass transition temperature can exceed 150° C. Moreover, while COC and COP may be attacked by non-polar solvents such as toluene, they nevertheless provide good chemical resistance to many other solvents. 
         [0081]    COC and COP may be extruded, coextruded, vacuum formed, injection molded, and can be terminally sterilized with EtO (ethylene oxide). Sterilization by irradiation may also be performed, but the polymer may discolor. Many polymers may exhibit birefringence when molded. High birefringence can weaken the part, and can also reduce the optical performance of the part. It would therefore be desirable to provide a polymer such as COP or COC than can be molded with low birefringence. 
         [0082]    Because of the desirable engineering properties of COC and COP, these polymers are promising for use in optical components such as in an illuminated surgical system like an illuminated retractor, laryngoscope, cannula, or the like. Use of COP will be discussed in many of the embodiments below, however, this is not intended to be limiting, and COC may also be used instead of COP. 
         [0083]    Exemplary COC polymers include Mitsui Chemicals, Inc. APEL™ APL5514ML and APL5014DP optical grade molding resins. Table 1 below summarizes some of the material properties of APEL™. Because this material has the minimum birefringence and highest refractive index of COC polymers, and because it may be processed with injection molding, it is a good candidate for use in optical components such as lenses or light waveguides. 
         [0000]    
       
         
               
               
               
               
             
               
               
               
               
             
           
               
                   
                 TABLE 1 
               
               
                   
                   
               
               
                   
                 Property 
                 APL5514ML 
                 APL5014DP 
               
               
                   
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Heat resistance (° C.) 
                   
                   
               
               
                   
                 T g  (Mitsui method, DSC) 
                 135 
                 135 
               
               
                   
                 TMA (Mitsui method, softening 
                 147 
                 147 
               
               
                   
                 point) 
               
               
                   
                 Melt flowability (g/10 min) 
                 36 
                 36 
               
               
                   
                 MFR (260° C., 2.16 kg) 
               
               
                   
                 Optical properties 
               
               
                   
                 Refractive index (n D ) 
                 1.54 
                 1.54 
               
               
                   
                 Abbe number 
                 56 
                 56 
               
               
                   
                   
               
             
          
         
       
     
         [0084]    Other exemplary COP polymers include Zeonex® and Zeonor® cyclo olefin polymers from Zeon Corporation (Tokyo, Japan). These COP polymers are desirable due to their optical properties, low water absorption, and high purity. Water absorption is less than 0.01%. Also, Zeonex® has a low specific gravity (approximately 1), thereby allowing optical components to be fabricated that are light weight. Also, Zeonex® COP has a relatively high heat resistance that is greater than acrylics such as polymethylmethacrylate (PMMA) while heat resistance is similar to that of polycarbonate (PC). COP also has excellent resistance to acidic and alkali chemicals, and is readily injection moldable. Several of the mechanical properties of various grades of Zeonex® and Zeonor® are summarized in Table 2 below. In addition to the mechanical and optical properties, some of the Zeonex® and Zeonor® COPs are also biocompatible based on testing conducted under ISO standard 10993 or under USP standards. A drug master file (DMF) has been established by the manufacturer. 
         [0000]    
       
         
               
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
               
             
           
               
                 TABLE 2 
               
               
                   
               
               
                   
                 Zeonex ® 
                 Zeonex ® 
                 Zeonex ® 
                 Zeonex ® 
                 Zeonex ® 
                 Zeonor ® 
                 Zeonex ® 
                 Zeonex ® 
               
               
                 Property 
                 480 
                 480R 
                 E48R 
                 330R 
                 RS820 
                 1020R 
                 690R 
                 790R 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Specific gravity 
                 1.01 
                 1.01 
                 1.01 
                 0.95 
                 1.01 
                 1.01 
                 1.01 
                 1.01 
               
               
                 Water 
                 &lt;0.01 
                 &lt;0.01 
                 &lt;0.01 
                 &lt;0.01 
                 &lt;0.01 
                 &lt;0.01 
                 &lt;0.01 
                 &lt;0.01 
               
               
                 absorption (%) 
               
               
                 Light 
                 92 
                 92 
                 92 
                 92 
                 White 
                 92 
                 92 
                 92 
               
               
                 transmittance, 
               
               
                 (%), 3 mm 
               
               
                 thickness 
               
               
                 Refractive index 
                 1.53 
                 1.53 
                 1.53 
                 1.51 
                 — 
                 1.53 
                 1.53 
                 1.53 
               
               
                 Glass transition 
                 138 
                 138 
                 139 
                 123 
                 138 
                 105 
                 136 
                 163 
               
               
                 temperature, ° C. 
               
               
                 Heat distortion 
                 123 
                 123 
                 122 
                 103 
                 123 
                 101 
                 136 
                 161 
               
               
                 temperature, ° C. 
               
               
                 (18.6 kgf/square 
               
               
                 cm, no annealing) 
               
               
                 Tensile 
                 59 
                 59 
                 71 
                 45 
                 43 
                 53 
                 61 
                 73 
               
               
                 strength, MPa 
               
               
                   
               
             
          
         
       
     
         [0085]    Table 3 below summarizes some of the mechanical and optical properties of various polycarbonate (PC) and polymethylmethacrylate (PMMA) polymers. 
         [0000]    
       
         
               
               
               
               
               
             
               
               
               
               
               
             
           
               
                   
                 TABLE 3 
               
               
                   
                   
               
               
                   
                   
                 PC 
                   
                   
               
               
                   
                   
                 Optical 
               
               
                   
                 Property 
                 Grade 
                 PC 
                 PMMA 
               
               
                   
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Specific gravity 
                 1.2 
                 1.2 
                 1.17-1.2  
               
               
                   
                 Water absorption (%) 
                 0.2 
                 0.15 
                 0.3  
               
               
                   
                 Light transmittance, 
                 89 
                 89 
                 92-95 
               
               
                   
                 (%), 3 mm thickness 
               
               
                   
                 Refractive index 
                 1.59 
                 1.59 
                 1.49 
               
               
                   
                 Glass transition 
                 121 
                 123-132 
                 74-99 
               
               
                   
                 temperature, ° C. 
               
               
                   
                 Tensile strength, MPa 
                 63 
                 67 
                 49-77 
               
               
                   
                   
               
             
          
         
       
     
         [0086]    Therefore, it would be desirable to provide a material such as COP or COC having a specific gravity greater than polycarbonate or PMMA (so the parts are lighter), and water absorption less than polycarbonate or PMMA. Water absorption affects index of refraction, therefore Zeonex and Zeonor are desirable since they are non-polar and hence hydrophobic with very low absorption. Additionally, it would be desirable to provide a material such as COP or COC that transmits light with greater efficiency than polycarbonate or greater efficiency or equal efficiency to that of PMMA. The COP or COC material also preferably has a glass transition temperature greater than polycarbonate or PMMA. At least some of the grades of COP or COC disclosed herein are also sterilizable with at least EtO without compromising optical properties of the component. 
         [0087]    Retractor illumination system  10  of  FIG. 1  includes blade retractor  12  including channel  13  to engage a fiber optic input  14  and waveguide illuminator  16 . Latch  17  serves to mechanically attach waveguide illuminator  16  to fiber optic input  14  so that the resulting assembly may be moved up and down in channel  13  to any position suitable for illumination. The optical coupling between fiber input  14  and waveguide illuminator  16  is a simple face-to-face coupling, which may be enhanced by use of an index matching gel, or other similar material, applied to either the fiber input  14  or the waveguide illuminator  16  or both. Light entering waveguide illuminator  16  is contained within the waveguide with minimal light loss until it reaches output optical structures such as output structures  18 , where light exits to illuminate the predetermined illumination area  20 . Output optical structures  18  may include one or more stair stepped facets or lenses that may include a radius or angled face, one or more prism structures, one or more diffraction gratings, applied optical film, or other optical structures designed to direct the available light to the predetermined illumination area  20 . 
         [0088]    In the cross-section view of  FIG. 1A  channels  13  of blade  12  engage waveguide illuminator  16 . Any suitable channel configuration may be used, such as, for example, a single channel with a circular or rhomboid cross-section. The section view of  FIG. 1B  shows a section of blade retractor  12 , waveguide illuminator  16  and fiber input  14 , with detail showing latch  17  which snaps into a hole or detent  14 D formed in fiber input  14  and the latch may be disengaged with a minor amount of force. Output optical structures  18  control and direct output light energy  21  which illuminates predetermined illumination area  20 . 
         [0089]    Alternate blade insert illumination system  22  of  FIG. 2  includes blade retractor  24  that includes light input section  26 , one or more light conduit sections such as light conduit section  27 , and a light output section such a light output section  28  that includes one or more output optical elements such as output optical elements  30 . In this configuration, light input section  26  has an integrated fiber optic input  32 . One or more fiber optic strands such as strands  32 A and  32 B may be integrated into the upper portion of light input section  26  by molding the strands into light input section  26 , gluing the strands into a formed receiving hole  26 R formed into the section, or other suitable methods. A light coupling element such as element  33  may also be included to improve light coupling and distribution. A collar such as collar  34  may be provided to aid in strain relief for the optical fiber input. Light directing structure  36  causes the light coming into the center of the waveguide illuminator to be directed along the sides of light input section  26 . The same light directing structure is shown in light conduit section  27 , serving to direct the light down to the next section. Light input section  26  and light conduit section  27  may be provided without the light directing structure, but this may result in a decrease in efficiency. 
         [0090]    Output optical element  30  may have a flat face to which an optical output film is applied to allow light to escape and direct the light toward tissues of interest, or output section  28  may have output optical film or molded structures located on or integrated into rear face  28 R that serve to send light out through output optical element  30 . 
         [0091]      FIG. 2A  shows the blade insert illuminator system of  FIG. 2  with light conduit section  27  removed to show the section attachment mechanism consisting of one or more male members such as engagement member  38  and a corresponding receptacle such as receptacle  39 . Output end  38 A of the male member  38  may also include one or more output transmission coupling structures or optical structures, e.g., a lens, such as lens  38 L to focus the light into the corresponding receptacle. Bottom  39 A of receptacle  39  may also include one or more input transmission coupling structures or optical structures, e.g., a lens, such as lens  39 L to spread light into its corresponding waveguide. In use, the male members are pressed into the female receptacles of the subsequent section and friction holds the sections together. 
         [0092]    In this configuration, light conduit section  27  of  FIG. 2  may be removed, allowing light input section  26  and light output section  28  to be directly connected together, for example, to fit a blade having a short length or to permit adjustment along the blade retractor of the waveguide element to adjust the location of the illumination area. One or more light conduit sections  27  may be added to the assembly to fit blades of medium or long length thereby providing a modular blade insert illumination system whose components may be mixed and matched as needed. For example, if more than one blade retractor is used in a procedure, one blade may be fitted with a shorter assembly of blade illumination components to illuminate the upper part of the surgical field and a second blade may be fitted with a longer assembly of blade illumination system components to illuminate the lower, deeper part of the surgical field. Sliding a blade insert illumination system up and down slightly within the blade channel allows the illumination area to be adjusted, for example, sliding the light output section closer to the work area increases the intensity of illumination and sliding it away from the work area provides a more diffuse, less intense illumination. In this way, the modular blade insert illumination system may be optimized for a particular type of work to be performed. 
         [0093]      FIG. 3  illustrates an alternate blade insert illumination system  40  inserted into blade  12 . Blade insert illumination system  40  includes light input section  40 A, one or more light conduit sections such as conduit sections  40 B and light output section  40 C. Bifurcated fiber optic cable  41  is integrated into light input section  40 A. This blade illuminator configuration includes an engagement arm  42  and light directing structure  44 . 
         [0094]      FIGS. 3A ,  3 B and  3 C illustrate details of arm  42  and light directing structure  44 . When two or more modular elements of blade insert illuminator system  40  engage channels  13 , the engagement arm  42  of first element  40 B engages adjacent element  40 A to maintain a secure optical connection at interface  45  between the elements. Arm  42  is a generally resilient member to permit flexing at joint  46  which permits tooth  47  to engage the light directing structure of the adjacent element. One or more light control elements such as light collecting lens  48  may be included at the input end of each blade illuminator element such as input end  49  of light output section  40 C. Similarly, light output lens  50  may be included at the bottom, exit or output end  51  of a light conduit section such as conduit section  40 B. Lenses  48  and  50  are illustrative of the use of optical structures to aid in the transmission of light between modules. Any other suitable optical structures such as angled facets, multi-faceted lens structures, spherical or aspherical lens may also be used.  FIG. 3C  illustrates how light travels in a blade insert illuminator conduit such as conduit element  40 B. Light from bifurcated fiber optic cable  41  first enters the top of light input section  40 A as illustrated in  FIG. 3 . Light energy  52  entering a blade illuminator waveguide such as conduit  40 B, either from the fiber optic cable or light collecting lens  48 , are guided by light directing structure  44  and light output lens  50 . 
         [0095]    Single element blade illuminator  54  is shown in  FIG. 4 . In this example, retractor  56  has a short blade  57 . When used with a retractor having a long blade, single element blade illuminator  54  may be adjusted along the length of the retractor blade to provide illumination wherever it is needed. 
         [0096]    In this configuration, a short section of fiber optic cable  58  is integrated into blade illuminator waveguide  60  at the output end and has any suitable connector  62  such as an industry standard ACMI connector or any other type of standard or proprietary connector, at the input end. Connector  62  is normally connected to a standard fiber optic light guide cable that conducts light from an external light source. Since blade insert illumination system  54  is made to minimize light loss, portable LED light sources may be attached directly to connector  62  or via a much shorter fiber optic light guide cable. Short section of fiber optic cable  58  is flexible and allows considerable latitude in how the connector  62  and light guide cable are oriented. For example, the connector  62  may be placed toward handle  56 H of retractor  56  or it may be placed on either side in order to keep out of the way of the surgeon and any other equipment that may be in use. 
         [0097]    Single element extended blade illuminator system  64  of  FIG. 5  is a simple blade insert illuminator designed to fit long blade retractors such a retractor  66 . Illuminator waveguide  68  receives light at input  69 , conducts light through total internal reflection throughout center portion  68 C, and output optical structures such as output structure  70  directs the light toward a predetermined area to be illuminated. 
         [0098]      FIGS. 4 and 5  illustrate that a blade insert illuminator may be provided in different sizes appropriate for the size of the retractor blade with which it is to be used. Blade insert illuminator  72  of  FIG. 5A  is an extended waveguide blade illuminator with a rigid light input component  73  in the place of the short section of fiber optic cable  58  as shown in  FIGS. 4 and 5 . Rigid light input component  73  allows all of the light guiding sections, waveguide  74  and rigid light input component  73 , to be molded as one device, thereby reducing cost of the assembly. Support gussets or flanges such as flanges  75  may be added to provide stability. Flanges  75  may have a coating or film applied to prevent light from escaping or may be made from a different material, for example, using a co-molding or overmolding process. Rigid light input component  73  may have an orthogonal input as shown, requiring light directing structure  76  to direct light from connector  62  down to waveguide  74  of the waveguide illuminator. Rigid light input component  73  may also be formed with a radius, as shown in  FIG. 5 , and using total internal reflection to guide the light from connector  62  to the body of the waveguide. Rigid light input component  73  may also be made rotatable, thereby allowing the fiber optic light guide cable to be positioned as needed around the surgical field to avoid interference with other instruments. 
         [0099]      FIG. 6  illustrates alternate modular blade insert illuminator elements  80 A and  80 B showing an alternative placement of latches  82  that hold the waveguide components together. Keeping the latches off to the side of the components, rather than in front as shown in  FIG. 3 , reduces the likelihood of the latches being accidentally disengaged or broken by surgical instruments during the course of a surgical procedure. Any other suitable mechanisms may be used to attach the modular components to each other, e.g., dovetail joints, tongue-and-groove joints, adhesives that are preferably index matching adhesives, etc., to optimize light coupling from one module to the next. The attachment mechanisms may also be separate from the optical path, for example, metal pins and sockets may be located in optically inactive areas of the modules. 
         [0100]      FIG. 7  is a side view of an alternate modular blade insert illumination system  84  wherein each subsequent waveguide section is lessened in thickness  85 . This allows output optical structures such as output structures  86  to be placed at the exposed end of the upstream waveguide, thereby allowing light to be directed from each waveguide section such as sections  84 A,  84 B,  84 C. Each waveguide component such as sections  84 A,  84 B may have a bottom surface that contains output optical structures  86  over much of its surface to act as a terminal illumination component in case no other subsequent waveguide components are attached. Light output section  84 C shows stepped output optical structure  88  on the front side and output optical structures  89  on the back side. Without output optical structures  88  that direct light out of the face, light would be lost out the end of light output section  84 C, therefore, the combination of output optical structures  88  and  89  contribute to higher efficiency through less lost light. 
         [0101]    Referring now to  FIG. 8 , winged blade insert illuminator  90  is shown engaged to retractor  91 . Illuminator  90  has integrated wings  92  that may serve an additional retracting function. Wings  92  are oriented generally parallel to long axis  87  of illuminator  90 . In this configuration, light is directed to exit output optical structure  94 . Light enters illuminator  90  via light input component  95 , which may be a fiber optic component or a rigid light conducting component at previously discussed. Because total internal reflection may allow light to enter wings  92 , the wings may need a reflective coating to prevent light from exiting the wings and being lost or shining into unwanted directions, such as back into the surgeons eyes. 
         [0102]      FIG. 9  illustrates another alternate blade insert illuminator  90 A that has a light directing element  96 , which serves to direct the light coming into the middle of the illuminator out toward the wings  92 A. Output optical structures such as structures  97  and  98  may be placed on wings  92 A and body respectively to provide illumination from both structures as shown by the arrows. 
         [0103]      FIG. 10  illustrates another alternate blade insert illuminator  90 B with an extended light directing element  96 B. In this embodiment, optical output structures are placed only on the wings  92 B so that illumination, light energy  99 , only exits through extended output structures  97 B in wings  92 B as shown by the arrows. Extended light directing element  96 B has reflective walls such as wall  93  that extend to output end  90 E of illuminator  90 B to maximize light reflected to the wings  92 B. This configuration also includes alternative latch arm  100  oriented near the interface with retractor  102  to engage cutouts or detents such as detents  103 A,  103 B and  103 C located in retractor  102 . Latch arm  100  maybe made of the same material as the waveguide or may be made of a different material for durability. For example, latch arm  100  may be made from steel or titanium and insert molded into illuminator  90 B. 
         [0104]    Alternatively, a retractor blade may be inserted into one or more slots in the illuminator waveguide to provide rigidity and or to enable cooperation with surgical site retention apparatus. 
         [0105]    Co-molded blade insert illuminator  104  of  FIG. 11  includes waveguide section  106  has been co-molded or over-molded with wing and body retractor portions  104 W and  104 B respectively, which are made of a different material. For example, retractor wing and body portions  104 W and  104 B may be made of a stronger, glass reinforced plastic or steel or titanium for strength while waveguide section  106  is molded from cyclo olefin polymer. 
         [0106]      FIG. 12  illustrates a McCulloch style retractor adapted to provide light into the surgical field. Illuminated retractor  107  is composed of retractor blade  108  and illumination blade  109 . Retractor blade  108  is shown as a McCulloch style retractor blade for use with a McCulloch retraction system although any suitable retractor and or retraction configuration may be used. Retractor blade  108  includes one or more mechanical connectors such a mechanical connector  108 M and neck slot or channel  110  to accommodate neck zone  124  and blade slot  111  to accommodate output blade  125  within retractor blade  108  while maintaining an air gap between active zones of the illumination blade and the retractor. Two or more engagement elements such as blade or plate  112  and tabs  114  secure illumination blade  109  to retractor blade  108 . Each tab  114  engages one or more engagement receptacles such as receptacles or recesses  115 . Plate  112  is joined to collar  116 , and when collar  116  removably engages input dead zone  122 D, the collar surrounds illumination blade input  118 . The removable engagement of collar  116  to input dead zone  122 D also brings plate  112  into contact with end surface  119  of the retractor blade. Collar  116  securely engages dead zone  122 D and surrounds cylindrical input zone  120  and forms input air gap  120 G. Engagement at dead zones minimizes interference with the light path by engagement elements such a plate  112  and tabs  114 . Plate  112  engages end surface  119  and tabs  114  resiliently engage recesses  115  to hold illumination blade  109  fixed to retractor blade  108  without contact between active zones of illumination blade  109  and any part of retractor blade  108 . 
         [0107]    Illumination blade  109  is configured to form a series of active zones to control and conduct light from illumination blade input  118  of the cylindrical input zone  120  to one or more output zones such as output zones  127  through and output end  133  as illustrated in  FIGS. 12 ,  13 ,  14  and  15 . Illumination blade  109  also includes one or more dead zones such as zones  122 D,  126 D and  126 E. Dead zones are oriented to minimize light entering the dead zone and thus potentially exiting in an unintended direction. As there is minimal light in or transiting dead zones they are ideal locations for engagement elements to secure the illumination blade to the retractor. 
         [0108]    Light is delivered to illumination blade input  118  using any conventional mechanism such as a standard ACMI connector having a 0.5 mm gap between the end of the fiber bundle and illumination blade input  118 , which is 4.2 mm diameter to gather the light from a 3.5 mm fiber bundle with 0.5 NA. Light incident to illumination blade input  118  enters the illumination blade through generally cylindrical, active input zone  120  and travels through active input transition  122  to a generally rectangular active retractor neck  124  and through output transition  126  to output blade  125  which contains active output zones  127  through  131  and active output end  133 . Retractor neck  124  is generally rectangular and is generally square near input transition  122  and the neck configuration varies to a rectangular cross section near output transition  126 . Output blade  125  has a generally high aspect ratio rectangular cross-section resulting in a generally wide and thin blade. Each zone is arranged to have an output surface area larger than the input surface area, thereby reducing the temperature per unit output area. 
         [0109]    In the illustrated configuration illumination blade  109  includes at least one dead zone, dead zone  122 D, generally surrounding input transition  122 . One or more dead zones at or near the output of the illumination blade provide locations to for engagement elements such as tabs to permit stable engagement of the illumination blade to the retractor. This stable engagement supports the maintenance of an air gap such as air gap  121  adjacent to all active zones of the illumination blade as illustrated in  FIG. 13 . Neck zone  124  ends with dimension  132  adjacent to output transition  126  which extends to dimension  134  at the output zones. The changing dimensions result in dead zones  126 D and  126 E adjacent to output transition  126 . These dead zones are suitable locations for mounting tabs  114  to minimize any effects of the engagement elements on the light path. 
         [0110]    To minimize stresses on the light input and or stresses exerted by the light input on the illumination blade, the engagement elements are aligned to form an engagement axis such as engagement axis  136  which is parallel to light input axis  138 . 
         [0111]    Output zones  127 ,  128 ,  129 ,  130  and  131  have similar configurations with different dimensions. Referring to the detailed view of  FIG. 14 , the characteristics of output zone  127  are illustrated. Each output zone is formed of parallel prism shapes with a primary surface or facet such a primary facet  140  with a length  140 L and a secondary surface or facet such as secondary facet  142  having a length  142 L. The facets are oriented relative to plane  143  which is parallel to and maintained at a thickness or depth  144  from rear surface  145 . In the illustrated configuration, all output zones have the same depth  144  from the rear surface. 
         [0112]    The primary facets of each output zone are formed at a primary angle  146  from plane  143 . Secondary facets such as facet  142  form a secondary angle  147  relative to primary facets such as primary facet  140 . In the illustrated configuration, output zone  127  has primary facet  140  with a length  140 L of 0.45 mm at primary angle of 27° and secondary facet  142  with a length  142 L of 0.23 mm at secondary angle 88°. Output zone  128  has primary facet  140  with a length  140 L of 0.55 mm at primary angle of 26° and secondary facet  142  with a length  142 L of 0.24 mm at secondary angle 66°. Output zone  129  has primary facet  140  with a length  140 L of 0.53 mm at primary angle of 20° and secondary facet  142  with a length  142 L of 0.18 mm at secondary angle 72°. Output zone  130  has primary facet  140  with a length  140 L of 0.55 mm at primary angle of 26° and secondary facet  142  with a length  142 L of 0.24 mm at secondary angle 66°. Output zone  131  has primary facet  140  with a length  140 L of 0.54 mm at primary angle of 27° and secondary facet  142  with a length  142 L of 0.24 mm at secondary angle 68°. 
         [0113]    Output end  133  is the final active zone in the illumination blade and is illustrated in detail in  FIG. 14 . Rear reflector  148  forms angle  149  relative to front surface  150 . Front surface  150  is parallel to rear surface  145 . Terminal facet  151  forms angle  152  relative to front surface  150 . In the illustrated configuration, angle  149  is 32° and angle  152  is 95°. 
         [0114]    Other suitable configurations of output structures may be adopted in one or more output zones. For example, output zones  127  and  128  might adopt a concave curve down and output zone  129  might remain generally horizontal and output zones  130  and  131  might adopt a concave curve up. Alternatively, the plane at the inside of the output structures, plane  143  might be a spherical section with a large radius of curvature. Plane  143  may also adopt sinusoidal or other complex geometries. The geometries may be applied in both the horizontal and the vertical direction to form compound surfaces. 
         [0115]    In other configurations, output zones may provide illumination at two or more levels throughout a surgical site. For example, output zones  127  and  128  might cooperate to illuminate a first surgical area and output zones  129  and  130  may cooperatively illuminate a second surgical area and output zone  131  and output end  133  may illuminate a third surgical area. This configuration eliminates the need to reorient the illumination elements during a surgical procedure. 
         [0116]      FIG. 16  illustrates COP laryngoscope illuminator  154  in use on a patient  155 . Laryngoscope  154  includes a handle  156  and a blade  157 . The handle  156  allows for grasping the laryngoscope  154 . The blade  157  is rigid and is attached to and extending from the handle. The blade is formed of cyclo olefin polymer that acts as a waveguide and further includes an illumination source. Blade  157  is for inserting into mouth  158  of a patient to allow viewing of a portion of the mouth, the pharynx, and the larynx of the patient  155 . Blade  157  is used to depress tongue  159  and mandible in order to prevent the tongue  159  of the patient  155  from obstructing the view of the medical professional during examination. When the illumination source is illuminated, electromagnetic waves (light) are able to propagate through blade  157  and illuminate the mouth and trachea of the patient. 
         [0117]      FIG. 17  illustrates the laryngoscope  154  of the laryngoscope illumination system in further detail. The laryngoscope  154  includes a handle  156  and a blade  157 . Blade  157  is formed of cyclo olefin polymer that acts as a waveguide. Blade  157  may have an illumination source disposed therein. The illumination source disposed within the blade comprises one or more LEDs  161  (light emitting diodes), battery  162 , a conductor  163  electrically connecting the battery and the LED, and an LED control circuit  164  and switch  165 . The LED is preferably a white-light LED, which provides a bright, white light. The battery may be provided in any form, but is preferably a lithium ion polymer battery. Blade  157  may also be detachable from the handle and disposable. The illumination source is in optical communication with the blade. When the illumination source is illuminated, light from the illumination source propagates through the blade illuminating predefined areas adjacent to the blade. 
         [0118]      FIG. 18  illustrates an alternate laryngoscope illumination system with the illumination source in the handle of the laryngoscope  154 . The laryngoscope  154  includes a handle  156  and a blade  157 . Blade  157  is formed of cyclo olefin polymer and performs as a waveguide. Handle  156  has an illumination source disposed therein. The illumination source disposed within the handle comprises one or more LEDs  161  (light emitting diodes), battery  162 , a conductor  163  electrically connecting the battery  162  and the LED  161 , an LED control circuit  164 , a switch  165  and an optical fiber  166  in optical communication between the LED  161  and the blade  157  for conducting light output  167  from the LED  161  to the blade  157 . 
         [0119]    The light output  167  of the optical fiber travels to one or more light directing surfaces such as surface  168  where it is directed toward output optical structures  169  on any suitable surface of the blade. Output optical structures  169  may direct illumination to particular anatomical areas through refraction while minimizing reflection that contributes to loss of light. The LED is preferably a white-light LED, which provides a bright, white light. The battery may be provided in any form, but is preferably a lithium ion polymer battery. The optical fiber  166  is secured in a channel provided in the laryngoscope  154 . LED  161  may be positioned in closer proximity to blade  157  such that light from LED  161  is captured directly by blade  157 , perhaps using optical structures on the light input portion of blade  157  that efficiently capture light from LED  161 , thereby obviating the need for optical fiber  166 . The handle  156  of this laryngoscope may serve as a heat sink for dissipating the heat generated by the LED, and additional heat sinks structures may be added. The handle may also be manufactured and provided separately from the blade of the laryngoscope  154 . This way, the blade  157  may be packaged separately from the handle to enable disposable use of the blade  157  with a non-disposable handle  156 . When the illumination source is illuminated, light from the illumination source propagates through the optical fiber to the blade illuminating the blade  157 . This in turn can illuminate the mouth and trachea of a patient. 
         [0120]    Cavity illuminator  172  of  FIG. 19  includes a COP waveguide insert  174  attached to blade  175 . The waveguide insert may be attached to the blade surface, e.g., with a suitable adhesive or other attachment means, or may be inserted into a channel formed in the blade to receive and hold the insert. The blade and handle may be separate pieces or integrated as a single device. In this embodiment, light from optical fiber  166  injects light into waveguide insert  174 , said light traveling along the waveguide insert to exit at one or more optical output structures positioned at one or more designated areas of the waveguide insert. Optical fiber  166  may be replaced by any other suitable light conduit, such as a rigid or flexible light pipe or waveguide. 
         [0121]    Referring now to  FIGS. 20 and 21 , cavity illumination system  178  includes COP waveguide insert  179 , the waveguide insert having an input connector  180  to couple light into the waveguide insert from an external light source, such as a fiber optic cable connected to any suitable light source such as a xenon or tungsten light source. Waveguide insert  179  may engage a channel  175   c  in the blade. The channel is designed to engage the insert. The waveguide insert is formed of cyclo olefin polymer. The waveguide may be made to be single use disposable or made to be suitable for multiple uses. The light source contained in the blade injects light into the waveguide insert, said light then is contained in the waveguide and travels to output optical structures in the waveguide insert that direct light to particular anatomic areas. 
         [0122]    Waveguide insert  179  as shown in  FIG. 22  may include output optical structures such as structures  182  in one or more suitable locations to direct light  184  to any appropriate anatomical areas. Output optical structures  182 , here, stair stepped facets such as facet  182 F, running a portion of the length of the top surface  186 T of the waveguide insert, each of facets  182 F causing a portion of the light  184  to exit the waveguide insert in a predetermined direction while minimizing light lost due to reflection at these structures in order to maintain high transmission efficiency. If the output optical structures abruptly end at an end face, light will shine out of this end face. However, the light that exits the end face may not serve as useful illumination and, hence, may be considered lost light that lessens the efficiency of the waveguide insert. To improve efficiency, one or more optical structures  187  may be arranged on bottom surface  186 B of to direct light out of the corresponding top surface  186 T, which may have microstructured optical components to diffuse or further direct the output light  188 . Combining the bottom face output optical output structures  187  with the top face output optical structures  182  increases the transmission efficiency of the waveguide insert. 
         [0123]      FIG. 23  is a side view of a COP speculum illumination system in a closed or insert position. Gynecological speculum  190  includes a first handle  191 , a second handle  192 , an upper blade  193  and lower blade  194 . The upper blade  193  and lower blade  194  are formed of cyclo olefin polymer that functions as a waveguide. Each blade may engage an illumination source or have an illumination source disposed therein. The illumination source disposed within the blades comprises one or more LEDs  196  (light emitting diodes), battery  197 , a conductor  198  electrically connecting the battery and the LED, and an LED control circuit  199  and switch  200 . The LEDs such as LED  196  are preferably a white-light LED, which provides a bright, white light. Battery  197  may be provided in any form, but is preferably a lithium ion polymer battery. The blades may also be detachable from the handle and disposable. The illumination source is in optical communication with the respective blade. When the illumination source is illuminated, light from the illumination source propagates through the blade providing illumination from appropriate areas of the blade. 
         [0124]    Referring now to  FIG. 24 , handles  191  and  192  are closed to separate blades  193  and  194 . In this orientation, blades  193  and  194  may direct light into any cavity in which the device is engaged. Any suitable structure, or structures such as coating  201 , facets  202  and or micro optical structures  203  may be incorporated into blades  193  and or  194  to control and direct illumination, however, such structure or structures must be specifically designed to maximize light transmission efficiency and minimize light loss and must be specifically designed to direct light to specific anatomic structures. For example, structures  202  may designed to direct more diffuse light to illuminate a substantial portion of the vaginal wall, or may be designed to direct more focused light to illuminate the cervix at the end of the vaginal cavity, or may be designed to provide both types of illumination. Single or multiple refractive and/or reflective structures, which may be combined with microstructured optical components, may be used to maximize light transmission efficiency to allow lower power light sources to be used, thereby reducing heat generation and the need to provide cumbersome heat management devices and methods. 
         [0125]      FIG. 25  illustrates an alternate COP cavity illumination system with the illumination source in first handle  204  and second handle  206  of the speculum  210 . The speculum  210  includes a first handle  204  engaging upper blade  205 , and a second handle  206  engaging lower blade  207 . The upper and lower blades  205  and  207  are formed of cyclo olefin polymer that functions as a waveguide. Handles  204  and  206  have an illumination source disposed therein. The illumination source disposed within one or both handles comprises one or more LEDs such as LED  211  (light emitting diodes), battery  212 , a conductor  213  electrically connecting the battery and the LED, an LED control circuit  214 , a switch  215  and an optical fiber  216  in optical communication between the LED and a blade such as upper blade  205 . The optical output of the optical fiber  216  travels through the blade illuminating the anatomical area(s) of interest. The LED is preferably a white-light LED, which provides a bright, white light. The battery may be provided in any form, but is preferably a lithium ion polymer battery. The optical fiber is secured in a channel provided in the speculum. The handles of this speculum may serve as a heat sink for dissipating the heat generated by the LED, and additional heat sinks structures may be added. The handles may also be manufactured and provided separately from the blades of the speculum. This way, the blades may be packaged separately from the handle to enable disposable use of the blade with a non-disposable handle. When the illumination source is illuminated, light from the illumination source propagates through the optical fiber to the blades illuminating the upper blade and lower blade. This in turn can illuminate the vaginal cavity or any other cavity of a patient. 
         [0126]    Speculums with metal blades continue to be used. If a metal speculum is preferred, then a disposable waveguide insert, similar to that shown in  FIG. 19  or  FIG. 20 , may be provided. 
         [0127]    Speculum  220  of  FIG. 26  may be a disposable speculum comprised of a COP illuminating bottom blade  221  (waveguide blade) and a non-illuminating top blade  222 . Waveguide blade  221  has an input connector  224  for a suitable light source, such as a fiber optic cable  225  connected to an external xenon light source  226 . Light  228  enters the connector portion of the waveguide blade and travels up the handle portion to a light directing structure  230 , which directs the light 90 degrees toward the output optical structures  231  and  232  located along the bottom blade portion. 
         [0128]    If COP blade  221  has a solid cross-section as shown in  FIG. 26A , output optical structures such as structures  231  and  232  may extend the full width  234  of blade  221  as well. If the COP blade has a concave or cup-shaped cross-section as shown in  FIG. 26B , separate output optical structures may be located on edge faces  235  and  236  as well as on concave surface  237 . The output optical structures direct light to specific anatomic areas and such light may be more diffuse, more focused, or a combination of each. 
         [0129]    Cavity illumination system  238  of  FIG. 27  may include two COP waveguide blades,  221  and  239 . The bottom waveguide blade  221  is as described for  FIG. 26 . Top waveguide blade  239  may include a connector  240  for a separate light source or both the top and bottom waveguide blades may be connected to the same light source  241 . Top waveguide blade  239  may not need internal light directing structures, such as structure  230  in blade  221 , because its normal geometry may provide suitable reflecting surfaces for directing light  242  toward the output optical structures  239   a  and  239   b.  Top waveguide blade may have a similar output optical structure as the bottom waveguide blade. Together, the two blades provide even illumination of the entire cavity wall. Alternatively, each blade may have different output optical characteristics to provide complimentary illumination, each blade illuminating different areas or anatomy or providing illumination energy of different wavelengths. 
         [0130]      FIG. 28  illustrates a side view of a COP illuminating anoscope waveguide  250  with a proximal end  251  and a distal end  252  that is inserted into a patient&#39;s natural cavity such as the anal cavity. The anoscope waveguide  253  may also be used as a general speculum. The anoscope waveguide is formed of cyclo olefin polymer. It may also include an input connector  254  that serves to conduct light into the waveguide such that light is conducted around the entire circumference  255  of the waveguide tube. Output optical structures  256  are typically placed near the distal end on the inside wall  257  along all or a portion of circumference  255 . Output optical structures placed on the end face  258  or outside wall  259  might cause irritation to the cavity walls during insertion. If output optical structures are required on end face  258  or outside wall  259 , any suitable coating or material may be used to lessen the irritation to the patients body tissue during insertion of the waveguide. The output optical structures provide even illumination of the entire cavity wall. A reflective or prismatic surface may also be created on the proximal end face to send mis-reflected light rays back toward the distal output optical structures. 
         [0131]    Referring now to  FIG. 29  shows an example of a light directing structure that contributes to light distribution around circumference  255 . Light entering input connector  254  may be directed by a light control structure, such as structure  260 , which splits the incoming light and sends it down into the waveguide tube wall at an angle ensuring circumferential light distribution. 
         [0132]    Referring now to  FIG. 30 , optical waveguide  270  may include an alternate light coupling apparatus such as coupling  271 . Coupling  271  may provide mechanical support and optical conduit between optical input  272  and waveguide  270 . 
         [0133]    Distal end  276  as shown in  FIG. 31  includes one of more vertical facets such as facet  276 F within the distal end to disrupt the light spiraling within the waveguide. Also shown are structures such as structure  278  on the end face of the cannula which serve to direct light as it exits the end face. Shown are convex lenses, but concave lenses or other optical structures (e.g., stamped foil diffuser) may be employed depending on the desired light control. Stepped facets such as facets  279  and  281  are shown on the outside tube wall. The “riser” section, risers  279 R and  281 R respectively, of the stepped facet is angled to cause the light to exit and as a result the waveguide slides against tissue without damaging the tissue. The angle is generally obtuse relative to the adjacent distal surface. Steps may be uniform or non-uniform as shown (second step from end is smaller than the first or third step) depending on the light directional control desired. The steps may be designed to direct light substantially inwards and or toward the bottom of the tube or some distance from the bottom of the tube, or they may be designed to direct light toward the outside of the tube, or any suitable combination. The facets such as facets  87  and  89  may be each designed to direct light at different angles away from the waveguide and or may be designed to provide different beam spreads from each facet, e.g., by using different micro-structure diffusers on each facet face. 
         [0134]    Facets may be used on the inside surface of the COP waveguide, but if waveguide material is removed to form the facets, the shape of the waveguide may be changed to maintain the internal diameter of the bore generally constant to prevent formation of a gap is between the waveguide and a dilator tube used to insert the waveguide into the body. Said gap may trap tissue, thereby damaging it during insertion into the body or causing the waveguide to be difficult to insert. Thus the outer wall of the waveguide may appear to narrow to close this gap and prevent the problems noted. 
         [0135]    Referring now to  FIGS. 32 ,  33  and  34 , applied light energy  282  may be bifurcated to send light into wall  284  of COP waveguide or tube  286 . Light input  288  may be split in input coupling  290 . 
         [0136]    The bifurcated ends  290 A and  290 B of input  288  preferably enter tube wall  284  at an angle  291  to start directing light around the tube wall. Alternatively, the bifurcated ends  290 A and  290 B may each enter tube wall  284  at different angles to further control light distribution. The bifurcated ends may enter the tube wall orthogonally, but this may require a prism structure in the wall placed between the input and the output with the apex of the prism pointed at the input. The prism structure directs the light around the tube wall. A vertical prism structure, prism  292  is shown with apex  292 A of the prism pointed in toward the center of the tube. Prism structure  292  may direct a portion of the input light back underneath the inputs and contributes to directing light all the way around the tube wall. The position, angle and size of this prism relative to the input bifurcated end determines how much light continues in the tube wall in its primary direction and how much light is reflected in the opposite direction in the tube wall. 
         [0137]    Additional vertical prism structures or light disruption structures may be placed toward the bottom of the tube on the outside tube wall as shown in  FIGS. 32 ,  33  and  34 . One or more light extraction structures  294 , shown as circumferential grooves cut into the outside wall of the tube, may also be included to optimize the illumination provided below waveguide  286 . Light  287  traveling circumferentially in the tube wall will not strike the light extraction structures  294  with sufficient angle to exit waveguide  286 . Thus, vertical prism  296  or light disruption structures such as disruption prisms  296 A,  296 B,  296 C and  296 D may be necessary to redirect the light so that the light rays  287  will strike light extraction structures  294  and exit the tube wall to provide illumination. As shown in  FIG. 34 , vertical prism structures such as  296 A and  296 B have different depths around the circumference in order to affect substantially all of the light rays traveling circumferentially in the tube wall. Vertical prisms of constant depth would not affect substantially all of the light rays. 
         [0138]      FIG. 33  also illustrates how a COP half-tube may be formed to provide illumination. At least one COP half-tube illuminator may be attached to the end of at least one arm of a frame, such as that used in Adson, Williams or McCulloch retractors. Such frames typically include two arms, but some frames have more than two arms. The arms of the frame are then moved apart to create a surgical workspace, with the at least one half-tube illuminator providing illumination of said space. One or more half-tube illuminators may also be provided with an extension that preferably is in contact with the opposite half tube and that serves to prevent tissue from filling in the gap created when the half tubes are separated. Tissue may enter this gap and interfere with surgery, so the extension helps reduce that issue. 
         [0139]      FIGS. 35 and 36  illustrate alternative configurations of an illumination waveguide. Proximal reflecting structures such as proximal structure  297  and proximal structure  298  may provide more complete control of the light within the waveguide with an associated weakening of the structure. 
         [0140]    Referring now to  FIGS. 37 and 38 , cross-sections  299  and  300  illustrate additional alternate light extraction structures of the distal end of an illumination waveguide. As shown with respect to  FIG. 31  above, depth  301  of light extraction structures such as structures  302  and  304  increases relative to the distance from the light input in order to extract most of the light and send the light out the inner tube wall  305  toward the bottom or distal end  306  of the tube. The light that remains in the tube wall below the extraction structures exits the bottom edge  307 , which may be flat or may have additional optical structures, e.g., a curved lens or a pattern of light diffusing structures such as structures  278  of  FIG. 31 . In  FIG. 37 , the distal 5-10 mm of the tube wall, window  308 , have no structures to enable this surface to operate as a window to the surrounding tissues to improve visualization of the surgical space. As illustrated in  FIG. 37 , light extraction structures  302  are formed of adjacent facets such as facets  302 A,  302 B,  302 C and  302 D forming angles  303  between adjacent facets. In this illustration angles  303  are obtuse. 
         [0141]    As illustrated in  FIG. 38 , light extraction structures  304  are formed of adjacent facets such as facets  304 A,  304 B,  304 C and  304 D forming angles  309  between adjacent facets. In this illustration angles  309  are acute. Any suitable angle may be used. 
         [0142]    It has been demonstrated that a clear waveguide cannula provides improved visualization of the entire surgical workspace because the surgeon can see the layers of tissue through the walls, thereby enhancing the surgeon&#39;s sense of depth and position, which are difficult to determine in an opaque cannula. Light exiting the side walls at the areas of tissue contact, due to changes in total internal reflection at these contact areas, serves to illuminate these tissues making them more visible than if a non-illuminated, non-waveguide clear plastic cannula is used. Alternatively, extraction structures  302  or  304  may extend all the way down to bottom edge  307 . 
         [0143]    Referring now to  FIGS. 39-42 , light input connector  312 C surrounds light input cylinder  312  which may be divided into multiple input arms such as arms  311  and  313  that then direct light into illumination waveguide  310 . Input arms  311  and  313  may assume any suitable shape and cross-sections depending on the optical design goals, such as the multi-radius arms with rectangular cross-section shown or straight sections (no radius) or angle rotators, etc. Also shown is a clamp flange holder  314  that serves to support input connector  312 C and arms as well as providing a standard light connector  312 C over input cylinder  312  (e.g., an ACMI or WOLF connector) and a flange  314 F at the top for attaching a clamp used to hold the entire structure in place once it is positioned relative to a surgical site in a body. A shelf or other similar light blocking structures may be added to the holder, extending over the input arms and or the upper tube edge as needed to help block any light that may escape these structures that might shine up into the user&#39;s eyes. Circumferential light extraction structures  316  are shown at the bottom, distal end  318 , of the tube. In the section view of  FIG. 40 , vertical light disruption structures or facets  276 F are shown on the inside wall of the tube. 
         [0144]    Illuminated cannula  310  of  FIG. 39  includes clamp adapter  314  that also support light coupling  312 C for introducing light energy into cannula  310 . The relative orientation of the clamp adapter and the light coupling as shown enables the clamp adapter to operate as a shield to prevent any misdirected light shining into the eyes of anyone looking into bore  310 B of the cannula, but the clamp adapter and light coupling may adopt any suitable orientation. 
         [0145]      FIG. 40  illustrates vertical facets  276 F within the distal end for disrupting the light spiraling within the waveguide. Circumferential light extraction structures  316  may include stepped facets such as facets  316 F and risers such as riser  316 R on the outside tube wall  310 W. The “riser” section of the stepped facet section  316 R is angled so that it may slide against tissue without damaging the tissue. Steps may be uniform or non-uniform depending on the light directional control desired. The steps may be designed to direct light substantially inwards and toward the bottom of the tube or some distance from the bottom of the tube, or they may be designed to direct light toward the outside of the tube, or both. 
         [0146]    Circumferential light extraction structures such as structures  316  may be facets or may be other geometries, such as parabolas. Circumferential light extraction structures coupled with light directing structures that provide circumferentially distributed light to the extraction structures provide circumferential illumination. Since tools entering the interior of the tube now have light shining on them from all sides, the tools do not cast any shadows within the cone of illumination emitted by the cannula. The circumferential illumination from a cylindrical waveguide creates a generally uniform cone of light that minimizes shadows, e.g., from instruments, creating substantially shadowless illumination in the surgical field below the tubular waveguide. 
         [0147]    COP Cannula  310  of  FIGS. 41 and 42  is illustrated without clamp flange/holder  314  in place. Input arms  311  and  313  above are offset above proximal surface  319  by a distance  320  and end in angled reflector surface  321  that partially extends down distance  322  into the tube wall. The offset controls the light entering waveguide  310  and restricts light entering to input structure  323 . Reflector surface  321  serves to direct light orthogonally from the horizontal input and down into the tube wall, also causing the light to spread around the circumference of the tube wall by the time the light reaches the distal or lower part of the tube. Reflector surfaces such as surface  321  may be a flat surface, an arced surface, or a series of interconnected surfaces and may also end at the top of the tube wall. Reflector surface  321  may be treated, e.g., a reflective or metallized coating or an applied reflective film, to enhance reflection. 
         [0148]    Air gaps may be used to isolate the light-conducting pathway in any suitable connector. Waveguide  310  of  FIG. 43  includes male connector  324 C that has been integrated with waveguide tube wall  310 W via bracket  325 . This allows connector  324 C to be molded with the waveguide and not attached as a separate part, such as standard light connector  312 C shown in  FIG. 39 . A separate connector introduces tolerance concerns into the system that may result in reduced coupling efficiency between a fiber optic cable output and waveguide input  326  because the two parts may not be aligned correctly. Molding the connector and the waveguide input as one piece substantially reduces the chance of misalignment and thereby increases coupling efficiency. 
         [0149]      FIG. 44  is a front view looking into input  326  of connector  324 C. Air gaps  327  are maintained around waveguide input  326  to isolate the light-conducting pathway. One or more small zones of contact such as contact zone  327 C may be maintained, essentially bridging connector  324 C and input  326  with a small amount of material, to add strength and stability to the system while resulting in minimum light loss in the contact zone. 
         [0150]    COP Waveguide  330  of  FIGS. 45 and 46  may be split open during surgery to permit greater access to the surgical field. Waveguide  330  is formed of cyclo olefin polymer. Light input channels  331  and  333  may be split and fed through a “Y”. Waveguide  330  is fully split front and back from the top to about ½-⅔ of tube by slots  334  and  336 . Alternatively, a waveguide may be split all the way to lower portion  330 L. Lower portion  330 L is scored inside and out with scoring such as score  337 . The scoring operates to redirect light that may be trapped circling the tube. Bottom element  340  may also be a COP element and is pre-split in half along edge  341  and may be glued or otherwise secured in a waveguide such as COP waveguide  330 . The generally planar shape of element  340  permits viewing through bottom element  340  and allows light to shine through. Alternatively, element  340  may also adopt any other suitable geometry such as rounded to form a lens. Because of the interface with the tube along edge  342  very little light is conducted into element  340 . Hole  343  enables a surgical screw or other suitable connector to engage through bottom element  340  of waveguide  330  to a surgical site. Splitting waveguide  330  and bottom  340  frees the waveguide elements from a connector through hole  343 , and permits the waveguide elements to be removed from the surgical site. While at least one light extraction structure is preferably located in lower portion  330 L on each tube half, the at least one extraction structure may be located on only one half or may be located further up the tube, e.g., near the end of split  334  and or split  336 . 
         [0151]    COP waveguide  344  in  FIG. 47  has reflector face  345  extending down the side of waveguide  344  opposite light input  346 , effectively removing material  347 . Extended reflector face  345  serves to direct light circumferentially around the tube wall. This opens up the waveguide to provide improved access to the surgical space. In addition, it offers the opportunity to replace removed material  347  with more durable material to improve strength and or provide a second clamp flange holder and or to provide mounting for other devices, such as a CCD camera. 
         [0152]    Illuminated COP retractors such as cannula, waveguides, tubes and or sheaths may also benefit from extendable skirts or segments to prevent tissue encroaching on a surgical site. The extendable elements may also include interface surfaces to introduce light into the elements to enhance surgical site illumination and or provide off axis illumination to enhance shadows for better depth perception and tissue discrimination. 
         [0153]    The illuminated COP retractors as discussed above may also be made extendable or telescoping to enable a varying depths of surgery with a single thus device minimizing hospital inventory. The illuminating cannulas discussed may also be formed as an illuminating drill guide, either as a tube or as two half tubes, that may be used to hold and guide drill or burr tip while also providing illumination of the area being worked on. 
         [0154]    A COP illuminator may be characterized as having a light input portion, a light conducting portion and a light output portion. The light input portion of the COP illuminator receives light from an external light source. Such a light source may be an external light box, e.g., a xenon light box, to which one end of a fiber optic light guide cable is attached to conduct light to the surgical field. In this instance, the other end of the fiber optic cable would be the source of light for the blade insert illuminator, for example, by employing a mating connector on the illuminator so that it may connect to the fiber optic cable. The light input portion may also include a tab, finger or other projection extending from a dead zone to engage the retractor blade at the top or handle end, the projection may be permanently integrated or temporarily attached. 
         [0155]    The light conducting portion of the COP illuminator typically is responsible for conducting light from the light input section to the light output section. It may be simply a section of optical material designed to support total internal reflection that is integral with the light input and light output portions. Surface treatment, e.g., polishing or reflective coating, and the continuous air gap may be used to support total internal reflection. 
         [0156]    The light output portion of the COP illuminator may contain any suitable number of output zones of generally similar depth, each zone having specially designed output optical structures that control and direct light to escape the illuminator to shine onto a predetermined area of interest or to have a predetermined shape or footprint. Such structures may be molded or cut into the light output zones. In some configurations, two to eight output zones are provided. 
         [0157]    A cyclo olefin polymer air gap retractor illumination system includes any suitable retractor such as a McCulloch with a channel in the blade to accommodate an air gap illuminator. The COP illuminator has active portions in which light passes and inactive or dead zones in which light does not pass as a result of the configuration and orientation of the input, output and surfaces of the illuminator. The illuminator is formed to have an air gap surrounding any active portion of the illuminator extending from the light input to the light output portion. The dead zones may include elements to allow the illuminator to securely engage the retractor. The light output portion of the illuminator may contain any suitable number of output zones, each zone having specially designed output optical structures that control and direct light to escape the illuminator to shine onto a predetermined area of interest or to form one or more predetermined shapes or footprints. 
         [0158]    A COP blade insert illuminator may comprise one or more illuminator sections designed to engage a mating channel or channels formed in the blade. Blade insert illuminators may be characterized by having a light input portion, a light conducting portion and a light output portion. The blade illuminator may be oriented at any suitable position along the retractor blade channel. A COP blade illuminator may be adapted to temporarily or permanently attach to any other suitable surgical instrument such as for example, a Gelpi retractor. 
         [0159]    The light input portion of a COP blade insert illuminator receives light from an external light source. Such a light source may be an external light box, e.g., a xenon light box, to which one end of a fiber optic light guide cable is attached to conduct light to the surgical field. In this instance, the other end of the fiber optic cable would be the source of light for the blade insert illuminator, for example, by employing a mating connector on the illuminator so that it may connect to the fiber optic cable. The light input portion may include a short section of a light conducting material, such as for example, a suitable plastic or a fiber optic bundle, that is permanently integrated or temporarily attached. 
         [0160]    The light conducting portion of a COP blade insert illuminator typically is responsible for conducting light from the light input section to the light output section. It may be simply a section of optical material designed to support total internal reflection that is integral with the light input and light output portions. Any suitable surface treatment, such as for example, polishing, reflective coating, anti-reflective (AR) coatings and or dielectric coatings may be used to support total internal reflection. 
         [0161]    The light output portion of a COP blade insert illuminator contains specially designed output optical structures that allow light to be extracted from the illuminator to shine onto a predetermined area of interest. Such structures may be molded into the light output portion or such structures may be applied, for example, as a film. 
         [0162]    A COP blade insert illumination system may consist of a single illuminator that contains the light input, light conducting and light output portions in a simple, single device that acts as a waveguide. Such a system may also be comprised of different sections of illuminator components that attach together to form a complete system. In this case, there may be a light input section designed to receive light from a light source, one or more light conduit sections designed to conduct light from the light input section to a light output section, and a light output section containing the optical output structures that allow light to escape and illuminate a predetermined area of interest, said sections attaching together to form a complete system. Each section acts as a waveguide and may employ optical structures to polarize and or filter the light energy entering or exiting the waveguide. 
         [0163]    A COP blade insert illuminator must be designed and fabricated to maximize light transfer from the light source or fiber optic input cable and minimize light loss from the waveguide in order to provide an efficient light transmission system. Efficiency is particularly important for LED and other light sources, e.g., halogen or xenon lamps, because it directly determines the required brightness of the LED. An inefficient waveguide experiences significant light loss, typically 60% of light may be lost from input to output. Such a light guide would require a high power LED to provide sufficient light. A high power LED requires a lot of power and generates significant heat, thereby requiring large batteries and bulky and inconvenient heat sinking devices and methods that add to the size and increase the difficulty of using such a device. Other high power light sources often require noisy fans, which may disturb the medical personnel conducting a surgery or medical exam. Lamps used in high power light sources have a limited life time, requiring frequent and expensive replacement, due to the need to drive the lamp at high power levels to generate enough light. An efficient waveguide, one in which light loss is typically less than 30%, allows a much lower power LED or other light source to be used, thereby significantly reducing or eliminating the need for special heat sinking devices and methods, reducing cost, and improving the usability of the device. The design of an efficient blade insert illumination waveguide may involve special design of the light input portion of the waveguide to efficiently capture the incoming light, for example, by careful selection of numerical apertures or using a lens, design and fabrication of the light reflecting walls of the light conducting portion of the waveguide to maintain surface finish to maximize reflection and reduce light lost through refraction, the use of reflective or dampening coatings, the design of light directing optical structures that direct the light toward the light output optical structures while minimizing light loss through refraction, and or the design of light output optical structures that maximize light exiting the waveguide through refraction, particularly refraction of light in certain directions, while minimizing light lost through reflection. 
         [0164]    While the preferred embodiments of the devices and methods have been described in reference to the environment in which they were developed, they are merely illustrative of the principles of the inventions. Other embodiments and configurations may be devised without departing from the spirit of the inventions and the scope of the appended claims. Additionally, while the above is a complete description of the preferred embodiments of the invention, various alternatives, modifications, and equivalents may be used. For example, many of the optical components are disclosed as being formed from COP. One of skill in the art will appreciate that COC may also be used to form those components. Therefore, the above description should not be taken as limiting the scope of the invention which is defined by the appended claims.