Patent Publication Number: US-2022233062-A1

Title: Endoscope thermal reflector

Description:
BACKGROUND 
     The present disclosure relates to devices used in endoscopic surgery and, more particularly, to thermal reflectors for use in endoscopes. 
     Light guides transfer light from a light source to an endoscope. Light guides are typically sized to work with the largest endoscopes. When light guides are used with smaller endoscopes there are unavoidable losses at the connection point, because the amount of light that can be concentrated into the smaller endoscope fiber bundle area is limited by geometric properties of light. This leads to heat buildup at the connection point which may lead to discomfort for a user and a dangerous surgical situation. 
     Therefore it would be desirable to prevent unnecessary light and heat from reaching an endoscope. 
     SUMMARY 
     The present disclosure relates to an endoscope system with a reflector for reflecting some light back into a light guide to reduce heat in an endoscope. In an implementation, an endoscope system for use with a light guide has an endoscope; and a reflector configured for placement between the endoscope and the light guide. The reflector has a translucent portion for transmitting light from the light guide and a reflective portion for reflecting light from the light guide back into the light guide. 
     The endoscope may have a light post and the reflector may be configured for placement between the light guide and the light post. The reflector may have a flat reflective portion, an inwardly angled reflective portion or a curved reflective portion. The reflector may have an annular shape. A light source may be coupled to the light guide. 
     In another implementation, an endoscope system has an endoscope with a body; and a light post coupled to the body, the light guide having a first active area of light transmission. The endoscope system also has a light guide, the light guide having a second active area of light transmission and a connector for connecting the light guide to the light post. The endoscope system also has a reflector configured for placement between the light guide and the light post. The reflector has a translucent portion for transmitting light from the light guide and a reflective portion for reflecting light from the light guide back into the light guide. The first active area has a smaller diameter than the second active area. 
     The translucent portion may have a diameter corresponding to a diameter of the first active area. The reflector may have an outer diameter that is smaller than a diameter of the connector. Optionally, the translucent portion has a diameter corresponding to a diameter of the first active area; and the reflector is configured to fit inside of the connector. The reflector further may have a flat reflective portion, an inwardly angled reflective portion or a curved reflective portion. The reflector may have an annular shape with an inner diameter corresponding to a diameter of the first active area. A light source may be coupled to the light guide. 
     In another implementation there is disclosed a reflector for use in an endoscope system with an endoscope and a light guide, the reflector comprising a translucent portion for transmitting light from the light guide; and a reflective portion for reflecting light from the light guide back into the light guide. The reflector may be configured for placement between the endoscope and the light guide. The reflective portion may be flat, inwardly angled, or curved. Additionally, the reflector may have an annular shape. 
     These and other features are described below. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The features, aspects and advantages of the present invention will become better understood with regard to the following description, appended claims and accompanying figures wherein: 
         FIG. 1  is a schematic diagram of a endoscope system according to an implementation; 
         FIG. 2  is a cross sectional view of a light post taken along line  2 - 2  of  FIG. 1 ; 
         FIG. 3  is a cross sectional elevation view of a light post with a thermal reflector according to an implementation; 
         FIG. 4  is a cross sectional elevation view of a light post with a thermal reflector according to an implementation; 
         FIG. 5  is a cross sectional elevation view of a light post with a thermal reflector according to an implementation; and 
         FIG. 6  is a cross sectional elevation view of a light post with a thermal reflector according to an implementation. 
     
    
    
     DETAILED DESCRIPTION 
     In the following description of the preferred implementations, reference is made to the accompanying drawings which show by way of illustration specific implementations in which the invention may be practiced. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. It is to be understood that other implementations may be utilized and structural and functional changes may be made without departing from the scope of this disclosure. 
     With reference to  FIGS. 1 to 3 , an endoscope system  10  according to an implementation has an endoscope  12  with a shaft  14  and a body  16 . The body  16  has a light post  18  for receiving light from a light guide  20  coupled to a light source  22 . As used herein, the term “light post” is intended to include, for example and without limitation, standard and non-standard interfaces for accepting light from a light source. The light guide  20  may be removably connected to the light post  18  using a connector  24 , for example, a threaded connector, a snap fit connector or a friction (push on) fit connector. 
     The light source  22  may produce visible light. The light source  22  may also produce non-visible wavelengths of radiation, such as, for example, near infra-red radiation or ultraviolet radiation, that may be transmitted with or without visible light. As used herein, the term “light” includes visible light as well as non-visible wavelengths of radiation. The light source  22  may have, for example, a xenon lamp or a light emitting diode (LED) lamp. 
     As used herein, the term “light guide” includes any waveguide or cable for transmitting light from a light source to an endoscope. For example and without limitation, the light guide  20  may be a flexible cable with fiber optics  26  for transmitting light from the light source  22 . Light is transferred from the light guide fiber optics  26  into endoscope fiber optics  28 . Representative fiber optics  26 ,  28  are shown in  FIG. 1 . Although fiber optics are used to illustrate certain implementations, this disclosure is intended to encompass other means of light transfer through the light guide  18  and through the endoscope  12 . 
     The light guide  20  may have an active diameter of light transmission (for example, the diameter of a fiber optic bundle) greater than an endoscope  12  active diameter of light transmission. For example, some light guides have an active diameter greater than about 4.5 mm and some endoscopes have an active diameter less than about 4 mm. Other endoscopes may have an active diameter of less than about 3 mm or less than about 2 mm; with some endoscopes having an active diameter as small as 0.5 mm. When a light guide has a greater active diameter than the endoscope then some light is not transferred from the light guide fiber optics into the endoscope fiber optics, but rather is transferred onto the light source post  18 . In addition, this tapering from light guide to endoscope excites higher angles and broadens the field of view of the exiting illumination. This constraint prevents optimization for efficiency. 
     As shown in  FIG. 3 , a thermal reflector  30  according to an implementation is configured for positioning proximal to an interface between the light guide fiber optics  26  and the endoscope fiber optics  28 . The thermal reflector  30  is configured with a translucent portion  32  to allow light to pass through an area corresponding to the endoscope active diameter and a reflective portion  34  to reflect light directed to areas outside of the endoscope active diameter. As illustrated below, the reflective portion  34  may be flat (perpendicular to the direction of light from the light guide  20 ), angled or curved. 
     The thermal reflector  30  may be made of glass, clear plastic, or metal. The reflective portion  34  may be manufactured by polishing metal or depositing a reflective coating of metal, such as aluminum or silver onto a portion of the glass or plastic. Thin film deposition may be used to create the reflective coating. The thermal reflector  30  has an outer diameter  36  that is slightly smaller than an inner diameter of a light guide connector  24  so that the thermal reflector may sit within the connector when the connector is attached to the light post. The thermal reflector  30  may have an outer diameter  36  of from about 3 mm to about 20 mm and more preferably from about 8 mm to about 13 mm. The thermal reflector may have a height of from about 5 to about 15 mm and more preferably from about 7.5 mm to about 12.5 mm. In an implementation, the thermal reflector  30  is specific to the endoscope fiber optics  28  and reflects light from about 10% to about 95% of the light guide fiber optics  26 . Depending on a diameter of the endoscope fiber optics  28 , the reflective portion  34  may have an inner diameter less than about 4 mm, and possibly less than about 2.3 mm, and possibly less than about 0.9 mm. 
     In an additional implementation, as shown in  FIG. 4 , a thermal reflector  38  has a reflective portion  40  that is annularly shaped with a flat reflective surface. The thermal reflector  38  has an inner diameter  42  that is slightly larger than the endoscope fiber optic active diameter. The thermal reflector  38  has an outer diameter  43  that is slightly smaller than an inner diameter of a light guide connector  24  so that the thermal reflector may sit within the connector when the connector is attached to the light post. The reflective portion  34  may be formed of, for example, aluminum or silver, or a thin film. 
     In an additional implementation, as shown in  FIG. 5 , a thermal reflector  44  has a translucent portion  46  and an inwardly angled reflective surface  48 . The reflective surface  48  may be at an angle less than about 10 degrees relative to an axis perpendicular to the direction of light from the light guide  20  so that light is reflected back into the light guide. The thermal reflector  44  may also be formed as an annular shape with the translucent portion  46  being an opening. 
     In an additional implementation, as shown in  FIG. 6 , a thermal reflector  50  is formed as an annular shape with a central opening  52  (translucent portion) formed by an inner wall  54  and a curved reflective surface  56 . The reflective surface  56  may have a consistent radius of curvature or more complex conic or freeform shape. The reflective surface may have a radius of curvature less than about 10 mm. The thermal reflector  50  may also be formed as an annular shape with the translucent portion  52  being an opening. 
     Optionally, the inner wall  54  conically tapers from a larger diameter, such as proximal to the light guide, to a smaller diameter, such as proximal to the light post. The inner wall  54  may also be reflective. The inner wall  54  may be configured to totally internally reflect light so that a surface treatment of the inner wall  54  is not necessary. The thermal reflector may also be formed as a cylindrical shape with a solid translucent portion (not shown). 
     Additionally, a converter (not shown) may be interposed between the light post  18  and the light guide connector  24  to allow for linkage of light posts and light guides having different diameters. A thermal reflector  34  may be placed in the connection between the light post and the converter. The thermal reflector  34  may also be placed in the connection between the converter and the light guide connector  24 . 
     The thermal reflector is advantageous in reducing heat caused by light that is not transmitted into an endoscope and allows for greater combinations of endoscopes and light sources. Additionally, the thermal reflector may be used in existing endoscope light systems without substantial modifications. Additionally, the thermal reflector is a relatively low cost solutions. 
     There is disclosed in the above description and the drawings, an endoscope thermal reflector that fully and effectively overcomes the disadvantages associated with the prior art. However, it will be apparent that variations and modifications of the disclosed implementations may be made without departing from the principles of the invention. The presentation of the implementations herein is offered by way of example only and not limitation, with a true scope and spirit of the invention being indicated by the following claims. 
     Any element in a claim that does not explicitly state “means” for performing a specified function or “step” for performing a specified function, should not be interpreted as a “means” or “step” clause as specified in 35 U.S.C. § 112.