Patent Publication Number: US-2019175300-A1

Title: Multiple-input-coupled illuminated multi-spot laser probe

Description:
PRIORITY CLAIM 
     This application claims the benefit of priority of U.S. Provisional Patent Application Ser. No. 62/598,653 titled “MULTIPLE-INPUT-COUPLED ILLUMINATED MULTI-SPOT LASER PROBE,” filed on Dec. 14, 2017, whose inventors are Jochen Horn, Alireza Mirsepassi, and Ronald T. Smith, which is hereby incorporated by reference in its entirety as though fully and completely set forth herein. 
    
    
     BACKGROUND 
     Field of the Disclosure 
     The present disclosure relates to a multiple-input-coupled illuminated multi-spot laser probe, and more specifically to systems and methods for creating multi-spot laser light beams, multiplexing an illumination light and the multi-spot laser light beams, and delivering the multiplexed light to a surgical handpiece via a multi-core optical fiber cable. 
     Description of Related Art 
     In many ophthalmic procedures a surgeon is required to use a variety of instruments in the patient&#39;s eye. For example, during a vitreoretinal surgery, a surgeon oftentimes manipulates a first handpiece for directing an illumination light beam onto the retinal surface in order to view patient anatomy and also manipulates an additional laser probe handpiece for delivering a laser treatment beam for treating the patient anatomy. However, there is a need for a multiple-input-coupled illuminated multi-spot laser probe. 
     SUMMARY 
     The disclosed embodiments of the present technology relates to multiple-input-coupled illuminated multi-spot laser probes, adaptors and other systems for multiplexing an illumination light and multi-spot laser light, and methods for multiplexing an illumination light and multi-spot laser light for and delivering the multiplexed light onto patient anatomy. 
     Some embodiments of the present technology involve a surgical laser system, an illumination light source, a surgical probe assembly, and a laser system port adaptor for creating a multi-spot pattern of laser light beams, multiplexing the multi-spot pattern of laser light beams with an illumination light beam, and delivering the multiplexed light beam to a surgical probe for simultaneously transmitting illumination light and a multi-spot pattern of laser light beams. The laser system port adaptor can include a first port arm for coupling with a laser source, a second port arm for coupling with an illumination system, a third port arm for coupling with a fiber optic cable of a laser probe, and a multiplexing intersection region. In some cases, the second port arm and the third port arm are substantially collinear across the intersection region, and the first port arm is substantially orthogonal to the second port arm and the third port arm at the multiplexing intersection region. 
     The intersection region of the laser system port adaptor can contain a diffractive optical element (DOE) configured to receive a collimated laser light beam from the optical element and to create a multi-spot laser pattern of laser light beams. In some cases, the DOE creates the multi-spot laser pattern of laser light beams as a 2×2 array pattern. 
     The intersection region can also contain a beamsplitter configured to reflect a plurality of narrow bands of the electromagnetic spectrum of light that correspond to the wavelengths of laser light emitted by the surgical laser system. The beamsplitter can further receive both the multi-spot pattern of laser light beams and an illumination beam from the illumination system. The beamsplitter can reflect the multi-spot laser pattern of laser light beams towards the third port arm and transmit portions of the illumination beam not contained within the at least two narrow bands of the electromagnetic spectrum towards the third port arm. In some cases, the second port arm includes a collimating lens for collimating the illumination light at the beamsplitter. Also, in some cases the intensity of the laser beams and the intensity of the illumination beam can be adjusted to produce a clear multiplexed multi-spot laser pattern of laser light beams and illumination beam. 
     The first port arm can include a ferrule having a diameter configured to securely couple within a female port of the laser source and can include an opening for allowing a focused laser spot from the laser source to enter the first port arm. The first port arm can also include an optical element for collimating a laser light beam. In some cases, the first port arm and the optical element have lengths configured to place the optical element substantially adjacent to the point of the focused laser spot from the laser source. Also, the first port arm can include external threading which, when tightened with a nut, couples the first port arm with the female port of the laser source and keeps the optical element substantially adjacent to the point of the focused laser spot from the laser source. 
     The third port arm can include a condensing lens substantially adjacent to the beamsplitter in the multiplexing intersection region. The condensing lens can be selected to focus the multi-spot laser pattern of laser light beams and the illumination beam onto an interface of the terminal end of a multi-core optical fiber cable of the surgical probe assembly. 
     The multi-core optical fiber cable can include a first outer core surrounded by an outer-core cladding and a plurality of inner cores contained within the outer core, each inner core in the plurality of inner cores surrounded by an inner-core cladding. In some cases, the plurality of inner cores contained within the outer core form a 2×2 array that matches a 2×2 multi-spot pattern of laser light beams from the DOE. 
     The materials for the various cores and the various claddings can be selected such that the focused illumination beam is propagated down an entire length of a first outer core of the multi-core optical fiber cable and such that each of the laser light beams in the multi-spot laser pattern of laser light beams is propagated down an entire length of one of a plurality of inner cores contained within the outer core. 
     In some cases, a refractive index of the outer core is greater than a refractive index of the outer-core cladding, a refractive index of each of the inner cores in the plurality of inner cores is greater than a refractive index of the inner-core cladding, and a refractive index of each or the inner cores in the plurality of inner cores is larger than the refractive index of the outer-core cladding. Further, the condensing lens can be selected to focus each of the laser beams in the multiplexed multi-spot pattern of laser light beams onto an interface with a respective inner core in the plurality of inner cores, wherein a spot size of each of the focused laser beams, an angular spread of each of the focused laser beams, a refractive index of the inner core, and a refractive index of the inner-core cladding causes the laser light beams to spatially fill and propagate through the plurality of inner cores for the length of the multi-core optical fiber cable. 
     Likewise, the condensing lens can be selected to focus the illumination beam as a light cone with a spot size to fall incident on at least a portion of the first outer core, at least a portion of the plurality of inner cores, and at least a portion of the inner-core claddings. The light cone of the illumination beam can include a narrow half-angle portion of the light cone and a wide half-angle portion of the light cone. In these cases, the refractive index for the various cores and claddings of the multi-core optical fiber cable and an angle of the narrow half-angle and wide half-angle portions of the light cone causes the illumination beam to spatially fill and propagate the length of the outer core of the multi-core optical fiber cable. Also, the narrow half-angle portion of the illumination beam can be confined within the outer core region, and the wide angle portion of the illumination beam is free to propagate within the outer core region, the inner cladding regions, and the inner core regions. 
     In some cases, the surgical probe assembly includes a ferrule for coupling with a laser system port adaptor or other multiplexing system. The surgical probe assembly can also include the multi-core fiber cable and a handpiece with a probe tip coupled with the distal end of the multi-core optical fiber cable. The probe tip can have a lens located substantially at a distal end of the probe tip and the multi-core optical fiber cable can terminate in an interface with the lens. The lens can be selected to translate the geometry of the multiplexed multi-spot laser pattern of laser light beams and illumination beam from the distal end of the multi-core optical fiber cable onto a target surface. 
     Some embodiments of the present technology involve methods of multiplexing a multi-spot pattern of laser light beams with an illumination light beam. The methods can involve directing a laser light beam to an optical element for collimating the laser light beam and directing the collimated laser light beam to a diffractive optical element (DOE) to create a multi-spot laser pattern of laser light beams. Likewise, the methods can involve directing the multi-spot pattern of laser light beams and an illumination light beam to a beamsplitter. Next, the method involves the beamsplitter reflecting the multi-spot pattern of laser light beams towards a condensing lens and transmitting the illumination light beam to the condensing lens, thereby multiplexing the multi-spot pattern of laser light beams and a transmitted illumination beam. The methods can also involve the condensing lens focusing the multiplexed multi-spot pattern of laser light beams and transmitted illumination beam onto an interface with a multi-core optical fiber cable. Also, the methods can involve directing the multiplexed multi-spot pattern of laser light beams and transmitted illumination beam through the multi-core optical fiber cable and onto a lens in a probe tip. Next, the lens translates a geometry of the multiplexed multi-spot laser pattern of laser light beams and illumination beam from the distal end of the multi-core optical fiber cable onto a target surface. 
     Some embodiments of the present technology involve methods of creating an image of a multiplexed beam of multi-spot pattern of laser light beams and illumination light. The methods can involve selecting, for a multi-core optical fiber cable, a material with a first refractive index for an outer core, a material with a second refractive index for an outer-core cladding, a material with a third refractive index for a plurality of inner cores contained in the outer core, and a material with a fourth refractive index for an inner-core cladding for each of the plurality of inner cores. The methods can also include determining a numerical aperture of laser light beams from a laser source and a numerical aperture of an illumination light beam from an illumination light source, and selecting a condensing lens to focus the multiplexed multi-spot pattern of laser light beams and illumination beam onto an interface plane of the multi-core optical fiber cable. Next, the methods can include multiplexing a multi-spot pattern of laser light beams with the illumination light beam and focusing the multiplexed multi-spot pattern of laser light beams and illumination beam onto an interface plane of the multi-core optical fiber cable such that the illumination beam propagates down the outer core and the laser beams propagate down the multiple inner cores. The methods can also involve directing the multiplexed beam of multi-spot pattern of laser light beams and illumination light through a lens in the surgical handpiece. 
     Some embodiments of the present technology involve an integrated illumination and multi-spot laser multiplexing system. The integrated system can include a laser source that emits a collimated laser light beam and a diffractive optical element (DOE) configured to receive the collimated laser light beam and to create a multi-spot laser pattern. The integrated system also includes an illumination system that emits substantially white light and a collimating lens that collimates the substantially white light received from the illumination system. The integrated system further includes a fiber optic cable port that couples a multi-core optical cable fiber to the system and a beamsplitter that reflects the multi-spot laser pattern towards a condensing lens and that transmits the collimated illumination beam towards the condensing lens, thereby multiplexing the multi-spot laser light beams and the illumination light beam. The condensing lens can further focus the multiplexed multi-spot pattern of laser light beams and illumination beam onto an interface with the fiber optic cable port, through a multi-core optical fiber cable, and onto a lens in the tip of a surgical handpiece that translates a geometry of the multiplexed multi-spot laser pattern of laser light beams and illumination beam onto a target surface. 
     Some embodiments of the present technology involve an integrated illumination and multi-spot laser multiplexing system. The system can include a laser source that emits a collimated laser light beam, a diffractive optical element (DOE) to create a multi-spot laser pattern of laser light, an illumination system that emits substantially white light, and a collimating lens that collimates the substantially white light received from the illumination system. The system further includes a beamsplitter that reflects the collimated laser light beam and that transmits the collimated illumination beam towards a condensing lens. The DOE creates a multi-spot laser pattern of laser light beams and the beamsplitter multiplexes the pattern of laser light beams and the illumination light beam. The system further includes a fiber optic cable port that couples the multiplexed light with a multi-core optical cable fiber. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a more complete understanding of the present technology, its features, and its advantages, reference is made to the following description, taken in conjunction with the accompanying drawings, in which: 
         FIG. 1  illustrates a system for creating a multi-spot pattern of laser light beams, multiplexing the multi-spot pattern of laser light beams with an illumination light beam, and delivering the multiplexed light beam to a surgical probe in accordance with a particular embodiment of the present disclosure; 
         FIG. 2A  illustrates a laser system port adaptor in accordance with a particular embodiment of the present disclosure; 
         FIG. 2B  illustrates the laser system port adaptor coupled with a surgical laser system and an illumination light source in accordance with a particular embodiment of the present disclosure; 
         FIG. 3  illustrates a method for multiplexing a multi-spot pattern of laser light beams and illumination light in accordance with a particular embodiment of the present disclosure; 
         FIG. 4A-4B  illustrate systems including a light multiplexing component containing a laser source and an illumination light source in accordance with a particular embodiment of the present disclosure; 
         FIG. 4C  illustrates a system that includes a laser light multiplexing module containing a laser source and an illumination module that includes an illumination light source in accordance with a particular embodiment of the present disclosure; 
         FIG. 5A  illustrates the top view of a terminal end of a multi-core optical fiber cable in accordance with a particular embodiment of the present disclosure; 
         FIG. 5B  illustrates a side view of the interface of a plurality of light cones onto a multi-core optical fiber cable in accordance with a particular embodiment of the present disclosure; 
         FIG. 5C  illustrates the cut-away view of a multi-core optical fiber cable in accordance with a particular embodiment of the present disclosure. 
         FIG. 5D  illustrates a proximal, interface end of a multi-core optical fiber cable with laser beam spots lining up with the inner cores and an illumination light beam spot lining up with the outer core in accordance with a particular embodiment of the present disclosure; 
         FIG. 5E  illustrates the distal end of a multi-core optical fiber cable with all three beams spread out to totally spatially fill their respective cores in accordance with a particular embodiment of the present disclosure; 
         FIGS. 5F-5M  illustrate the propagation of the multiplexed light through a multi-core optical fiber cable in accordance with a particular embodiment of the present disclosure; 
         FIG. 5N  illustrates a cut-away view of a multi-core optical fiber cable in accordance with a particular embodiment of the present disclosure. 
         FIG. 6A-6B  illustrate an open side views of tips of a surgical hand probe in accordance with a particular embodiment of the present disclosure; 
         FIG. 7  illustrates a method of creating an image of a multiplexed beam of multi-spot pattern of laser light beams and illumination light in accordance with a particular embodiment of the present disclosure; 
         FIG. 8A  illustrates an end view of a multi-lumen tubing for delivering multiplexed laser aiming and treatment beams and a laser illumination light beam in accordance with a particular embodiment of the present disclosure; 
         FIG. 8B  illustrates each of the laser aiming and treatment beams as well as the laser illumination light beam spatially underfilling their respective fiber cores at the proximal end in accordance with a particular embodiment of the present disclosure; 
         FIG. 8C  illustrates each of the laser aiming and treatment beams as well as the laser illumination light beam spatially totally filling their cores at the distal end in accordance with a particular embodiment of the present disclosure; and 
         FIG. 8D  illustrates a distal end of a nanofiber extending past an array of glass fibers in the multi-lumen tubing at or near a focusing lens in accordance with a particular embodiment of the present disclosure. 
     
    
    
     DESCRIPTION 
     In a wide variety of medical procedures, laser light is used to assist the procedure and treat patient anatomy. For example, a vitreoretinal surgery oftentimes involves using a laser treatment beam for photocoagulation of retinal tissue. Vitreoretinal procedures commonly involve a laser probe that is capable of alternately emitting an aiming laser beam to select target spots on retinal tissue and emitting a treatment laser beam to perform the photocoagulation at the targeted spots. Frequently, the laser probe utilizes light in a red band of the electromagnetic spectrum for the aiming beam and light in a green band of the electromagnetic spectrum for the treatment beam. Also, during a panretinal laser photocoagulation procedure, a surgeon selects thousands of spots on retinal tissue to apply the treatment laser beam to, resulting in a very long and tedious procedure. Therefore, a laser probe capable of producing a multi-spot pattern of laser light is desirable. 
     Vitreoretinal procedures also benefit from illumination light being directed into the eye and onto retinal tissue. Vitreoretinal surgeons oftentimes use a laser probe handpiece for delivering the laser aiming and treatment beams and also use an additional handpiece for directing an illumination light beam onto the retinal surface in order to view patient anatomy. 
     The field of vitreoretinal surgery, as well as other medical laser procedures, would benefit from multiplexing an illumination light and multi-spot laser light. Accordingly, the technology described herein involves multiple-input-coupled illuminated multi-spot laser probes, adaptors and other systems for multiplexing an illumination light and multi-spot laser light, and methods for multiplexing an illumination light and multi-spot laser light and delivering the multiplexed light onto patient anatomy. 
       FIG. 1  illustrates a system  100  for creating a multi-spot pattern of laser light beams, multiplexing the multi-spot pattern of laser light beams with an illumination light beam, and delivering the multiplexed light beam to a surgical probe  115  for simultaneously transmitting illumination light and a multi-spot pattern of laser light beams in accordance with a particular embodiment of the present disclosure. 
     The system  100  includes a surgical laser system  105  that includes one or more laser sources for generating laser beams used during an ophthalmic procedure. For example, the ophthalmic surgical laser system  105  can alternatively generate a surgical treatment beam with a wavelength of around 532 nanometers (nm) and a laser aiming beam with a wavelength of around 635 nm. A surgeon or surgical staff member can control the surgical laser system  105  (e.g., via a foot switch, voice commands, etc.) to alternatively emit the laser aiming beam and fire the treatment beam to treat patient anatomy (e.g., perform photocoagulation). The laser beams can be emitted through a port  106  in the surgical laser system  105 . 
     The system  100  also includes an illumination light source  110  that can include one or more of a xenon illumination, an RGB light-emitting diode (LED) illuminator, a white light LED illuminator, a laser-pumped phosphor illuminator, a supercontinuum white laser illuminator, etc. The illumination light source  110  can be a surgical console that can monitor and control a wide variety of aspects of an ophthalmic procedure. For example, the surgical console can be configured for use in vitreoretinal surgery and can power and control vitrectomy probes, can integrate pressurized infusion delivery and intraocular pressure compensation, can provide surgical illumination, etc. In some cases, the illumination light source  110  can deliver the illumination light via an illumination cable  111 . 
     The system  100  also includes a laser system port adaptor  150  containing optical elements (not shown) for creating a multi-spot pattern of laser light beams from a laser light beam from the ophthalmic surgical laser system  105  and multiplexing the multi-spot pattern of laser light beams with an illumination light beam received from the illumination light source  110 . The adaptor  150  can include a plurality of port arms  152 ,  154 ,  156  that couple with the surgical laser source  105 , the illumination light source  110 , and to the surgical probe  115 , respectively. 
     The system  100  can deliver the multiplexed light beam from the port arm  156  to the surgical probe  115  via a multi-core optical fiber cable  130  to provide the surgical probe  115  the ability of simultaneously providing illumination light and a multi-spot pattern of laser light beams to the retina  120  of a patient&#39;s eye  125 . The surgical probe  115  includes a probe body  135  and a probe tip  140  that house and protect the multi-core optical fiber cable  130 . A distal end  145  of the probe tip  140  also contains a lens (not shown, described in greater detail below) that translates the multiplexed light beam from the distal end of the multi-core optical fiber cable onto the retina  120 . 
     As disclosed herein, various systems and methods can be employed for creating a multi-spot pattern of laser light beams multiplexing the multi-spot pattern of laser light beams with an illumination light beam. As briefly mentioned above, in some cases, a port adaptor can contain optical elements for creating a multi-spot pattern and multiplexing light beams.  FIG. 2A  illustrates a laser system port adaptor  250  according to some embodiments of the present disclosure. The laser system port adaptor  250  includes a first port arm  252  for coupling with a laser source, a second port arm  254  for coupling with an illumination system, and a third port arm  256  for coupling with a fiber optic cable of a laser probe. The laser system port adaptor  250  also includes a multiplexing intersection region  280  where the first port arm  252 , the second port arm  254 , and the third port arm  256  intersect. In some cases, the second port arm  254  and the third port arm  256  are substantially collinear across the multiplexing intersection region  280 , and the first port arm  252  is substantially orthogonal to the second port arm  254  and the third port arm  256  at the multiplexing intersection region  280 . 
     The first port arm  252  includes a ferrule  258  that functions as a male coupling for a female chimney port (not shown) of the laser system. The ferrule  258  has an opening  262  that allows laser light from the laser source to enter the first port arm  252 . Also, the ferrule  258  can house an optical element  264  contained within the ferrule  258 . The optical element  264  is configured to collimate laser light received from the laser source. For example, the optical element  264  can be a graded-index (GRIN) lens with a length and a pitch selected such that the optical element  264  collimates laser light received at the opening  262  at a selected distance adjacent to a diffractive optical element (DOE)  282  contained within the multiplexing intersection region  280 , as described in more detail below. 
     The first port arm  252  also includes an external threading  260  to draw the first port arm substantially all the way into the female port of the surgical laser system  105  when a nut is tightened on the external threading. In some cases, the optical element  264  is positioned within the ferrule  258  that is flush with the opening  262 , and the surgical laser system  105  is configured to focus a laser spot at the terminal end of the female port. Accordingly, the external threading  260  can facilitate the optical element  264  being positioned at a point relative to the surgical laser system  105  such that a focused laser spot of a laser produced by the surgical laser system falls substantially incident onto the end of the optical element  264 . 
     The second port arm  254  for coupling with an illumination system can comprise a female port having a substantially cylindrical external frame  266 , an internal cavity  268 , a collimating lens  270  at a first end of the internal cavity  268 , and an opening  272  at the second end of the internal cavity  268 . The internal cavity  268  of the second port arm  254  can be configured to receive a ferrule of an optical cable  111  that delivers an illumination light beam from the illumination light source  110 . In some cases, the ferrule of the optical cable that delivers an illumination light beam is secured to the second port arm  254  with a nut such that the illumination emitted from an optical fiber contained within the optical cable spreads to fall incident onto the collimating lens  270  such that the collimating lens  270  delivers substantially collimated illumination light to a beamsplitter  284  contained in the multiplexing intersection region  280 . 
     The third port arm  256  for coupling with a fiber optic cable of a laser probe can comprise a female port having a substantially cylindrical external frame  274 , an internal cavity  276 , a condensing lens  278  at a first end of the internal cavity  276 , and an opening  275  at the second end of the internal cavity  276 . 
     The internal cavity  276  of the third port arm  256  can be configured to receive a ferrule of a multi-core optical fiber cable  130  that delivers multiplexed light to the surgical probe  115 , as explained in greater detail below. In some cases, the ferrule of a multi-core optical fiber cable is secured to the third port arm  256  with a nut such that the condensing lens  278  precisely focuses the multiplexed light onto an interface  290  of the terminal end of the multi-core optical fiber cable such that an illumination beam and laser aiming/treatment beams are propagated down an entire length of the multi-core optical fiber cable, as explained in greater detail below. 
     As explained above, the laser system port adaptor  250  also includes a multiplexing intersection region  280  where the first port arm  252 , the second port arm  254 , and the third port arm  256  intersect. The multiplexing intersection region can contain a diffractive optical element (DOE)  282  configured to receive a collimated laser light beam from the optical element  264  of the first port arm  252  and to create a multi-spot laser pattern of laser light beams. The DOE  282  can be selected to diffract incident laser light into a multi-spot pattern that will align with an intended target geometry. For example, the DOE  282  can be selected to create a 2×2 array pattern of laser light beams that substantially matches a 2×2 array of inner cores of a multi-core optical fiber cable that delivers the multiplexed light to the surgical probe  115 , as explained in greater detail below. 
     The multiplexing intersection region  280  also contains a beamsplitter  284  configured to reflect a portion of the light spectrum and transmit a remaining portion of the light spectrum. More specifically, the beamsplitter  284  can be configured to both: a) reflect laser aiming and treatment beams from the surgical laser system  105  toward the third port arm  256  and the condensing lens  278 , and b) transmit the illumination light from the illumination light source  110  toward the third port arm  256  and the condensing lens  278 . Also, as mentioned above, the condensing lens  278  can be selected to precisely focus the multiplexed light onto an interface  290  of the terminal end of the multi-core optical fiber cable  130  such that an illumination beam and laser aiming/treatment beams are propagated down an entire length of the multi-core optical fiber cable  130 , as explained in greater detail below. 
     As explained above, vitreoretinal procedures frequently utilize light in a red band of the electromagnetic spectrum for a laser aiming beam and light in a green band of the electromagnetic spectrum for a laser treatment beam. Accordingly, the beamsplitter  284  can be configured to highly reflect light in a narrow band of the red spectrum and a narrow band of the green spectrum and configured to transmit the remaining electromagnetic spectrum. In some embodiments, the beamsplitter  284  reflects light in a first narrow band around 532 nanometers (nm) and in a second narrow band around 635 nm and transmits the remaining spectrum. The beamsplitter  284  can be a dichroic beamsplitter cube, a beamsplitter plate, etc. 
     Since portions (e.g., red and green portions) of the illumination light from the illumination light source  110  are reflected by the beamsplitter  284 , the system port adaptor  250  can include a light collection module  286 . For example, the light collection module  286  can be a beam dump, power monitor, etc. 
       FIG. 2B  illustrates the laser system port adaptor  250  coupled with a surgical laser system  205 , a ferrule  212  of an optical cable  111  that delivers an illumination light beam from the illumination light source  110 , and a ferrule  132  of the multi-core optical fiber cable  130  that delivers multiplexed light to the surgical probe  115 . 
     The surgical laser system  205  includes a female port  202  with an opening  206  in the proximal end of the female port  202  that allows laser light to exit the surgical laser system  202 . The female port  202  is configured to receive the first port arm  252  of the laser system port adaptor  250  such that the optical element  264  in the first port arm  252  is substantially adjacent to the opening  206 . The surgical laser system  205  is configured to focus laser light substantially onto an interface plane at the opening  206  and the optical element  264 . Also, a nut  204  can be used to secure the laser system port adaptor  250  with the surgical laser system  205  and maintain the proximity of the optical element  264  with the opening  206  in the female port  202 . 
     As explained above, an ophthalmic surgical laser system  105  can alternatively generate a surgical treatment beam with a wavelength of around 532 nanometers (nm) (i.e., green) and a laser aiming beam with a wavelength of around 635 nm (i.e., red). However, red and green incident laser light diffract off a DOE with different diffraction angles. When the laser beams are not collimated then their focus is also affected, i.e. red and green will focus at different axial locations. This greatly complicates trying to focus both green and red laser beams into the same inner-core regions of the multi-core fiber, as explained in greater detail below. Therefore, some embodiments involve collimating the multiple beams that fall incident on the DOE so that the multiple beams generated from the DOE are also collimated. To achieve a multi-spot laser pattern with sufficient focus, the laser light from the surgical laser system  205  should be collimated when it falls incident on the DOE  282 . Therefore, in some cases, the optical element  264  can selected to be long enough (e.g., 16.54 mm) to collimate laser light from the surgical laser system  205 , bring the laser light back into focus, and collimate the laser light a second time such that the laser light is collimated at the DOE  282 . 
     In some cases, the optical element  264  is a 0.75 pitch, 0.20 NA GRIN relay lens that receives laser focused input beam and outputs a collimated beam at the distal end of the GRIN lens. The GRIN lens is long enough to collimate the beam then bring it to a focus and then collimate is a second time. In some other cases, the optical element  264  is a refractive-lens relay system. 
     The DOE  282  receives the collimated laser light and creates a multi-spot pattern of laser light beams. For example, in some cases, the DOE  282  can create a 2×2 array pattern of laser light beams that substantially matches a 2×2 array of inner cores of the multi-core optical fiber cable  130  that delivers the multiplexed light to the surgical probe  115 , as explained in greater detail below. In some other cases, the DOE  282  can be replaced by an assembly of prisms and/or beamsplitters to create the multi-spot pattern of laser light beams. 
     As also shown in  FIG. 2B , the second port arm  254  of the laser system port adaptor  250  is also coupled with a ferrule  212  of an optical cable  111  that delivers an illumination light beam from the illumination light source  110 . In some cases, the length of the internal cavity of the second port arm  254  is selected such that a terminal end of an optical fiber contained within the optical cable  111  is positioned a predetermined distance from the collimating lens  270 . The collimating lens  270  and/or the predetermined distance of the optical fiber from the collimating lens  270  can be selected such that the illumination light is substantially fully collimated at the beamsplitter  284 . Also, a nut can secure the ferrule  212  in the internal cavity  268  and maintain the predetermined distance of the optical fiber  218  from the collimating lens  270 . 
     Also, as mentioned above, the beamsplitter  284  can be configured to both: a) reflect laser aiming and treatment beams from the surgical laser system  105  toward the third port arm  256  and the condensing lens  278 , and b) transmit the illumination light from the illumination light source  110  toward the third port arm  256  and the condensing lens  278 . 
     As also shown in  FIG. 2B , the third port arm  254  of the laser system port adaptor  250  is coupled with a ferrule  132  of the multi-core optical fiber cable  130  that delivers multiplexed light to the surgical probe  115 . Also, the condensing lens  278  can be selected to precisely focus the multiplexed light onto an interface  290  of the terminal end of the multi-core optical fiber cable  130  such that an illumination beam and laser aiming/treatment beams are propagated down an entire length of the multi-core optical fiber cable  130 , as explained in greater detail below. 
       FIG. 3  illustrates a method  300  for multiplexing a multi-spot pattern of laser light beams and illumination light in accordance with a particular embodiment of the present disclosure. The method  300  involves collimating a laser light beam by directing a laser light beam to a graded-index (GRIN) lens at step  305 , creating a multi-spot pattern of laser light beams by directing the collimated laser light beam onto a diffractive optical element (DOE) at step  310 , and directing the multi-spot pattern of laser light beams to a beamsplitter at step  315 . 
     The method  300  also involves collimating an illumination beam using a collimating lens at step  320  and directing the collimated illumination beam to the beamsplitter at step  325 . Next, the method  300  involves multiplexing, using the beamsplitter, the multi-spot pattern of laser light with the collimated illumination beam at step  330 . More specifically, in some cases, multiplexing the multi-spot pattern of laser light with the collimated illumination beam can involve the beamsplitter reflecting laser aiming and treatment beams from the surgical laser system toward a condensing lens and transmitting the illumination light from the illumination light source towards the condensing lens. 
     The method  300  also involves focusing, with a condensing lens, the multiplexed beam of multi-spot pattern of laser light and illumination light onto an interface with a multi-core optical fiber cable of a surgical handpiece at step  335  and, subsequently, directing the multiplexed beam of multi-spot pattern of laser light beams and illumination light through a lens in the surgical handpiece at step  340 , as described in more detail below. 
     In some cases, the intensities of the white illumination and the laser aiming beams can be adjusted (e.g., at the illumination light source and surgical laser system, respectively) to provide the right amount of laser aiming beam contrast against the white while providing enough white illumination to easily see the retina. 
     The system  100  illustrated in  FIG. 1  and described herein involves a modular approach with a separate surgical laser system and illumination light source. However, in some cases, the surgical laser system and illumination light source can be integrated in a single module and the module can contain the appropriate optics for creating a multi-spot pattern of laser light beams, multiplexing the multi-spot pattern of laser light beams with an illumination light beam, and delivering the multiplexed light beam to a surgical probe for simultaneously transmitting illumination light and a multi-spot pattern of laser light beams. 
       FIG. 4A  illustrates a system  400  that includes a light multiplexing component  402  containing a laser source  405  and an illumination light source  410  in accordance with a particular embodiment of the present disclosure. The laser source can generate substantially collimated laser beams (e.g., red aiming beams, green treatment beams) and direct the laser beams towards a beamsplitter  484 . Also, a linear slide  450  (or rotating wheel) can be positioned in the beam path between the laser source  405  and the beamsplitter  484 . The linear slide  450  can include multiple optical features that can be alternatively slid into the beam path between the laser source  405  and the beamsplitter  484 . For example, the linear slide  450  can include a diffractive optical element (DOE) that creates a multi-spot pattern of laser light beams and a clear window or a hollow section that allows the laser light to pass through unaffected, resulting in a single spot laser beam. 
     The illumination light source  410  can be a white LED, an RGB LED, a xenon laser, a pumped phosphor laser, discreet lasers, supercontinuum laser, etc. The illumination light source can generate and direct illumination light to a collimating lens  470  and towards the beamsplitter  484 . 
     The beamsplitter  484  can be configured to both reflect laser aiming and treatment beams from the laser source  405  toward a condensing lens  478  and transmit the collimated illumination light from the illumination light source  410  toward the condensing lens  478 . The condensing lens  478  can be selected to precisely focus the multiplexed light onto an interface  490  of the terminal end of the multi-core optical fiber cable  430  such that an illumination beam and laser aiming/treatment beams are propagated down an entire length of the multi-core optical fiber cable  430  and into a surgical hand piece  415 , as explained in greater detail below. 
       FIG. 4B  illustrates another system  400 ′ that includes a light multiplexing component  402 ′ containing a laser source  405  and an illumination light source  410 . Here, the beamsplitter  484  can multiplex laser light from the laser source  405  and collimated illumination light from the illumination light source  410  before the multiplexed light beam falls incident on a rotating wheel  450 ′. When the rotating wheel  450  positions a DOE into the beam path, the DOE can create a multi-spot pattern of laser light beams within the illumination light. Also, the system  400 ′ can include a condensing lens  478  to focus the multiplexed light beam onto an interface  490  of the terminal end of the multi-core optical fiber cable  430   
       FIG. 4C  illustrates another system  499  in accordance with a particular embodiment of the present disclosure that includes a laser light multiplexing module  403  containing a laser source  405  and an illumination module  407  that includes an illumination light source  410 . The illumination module  407  includes a collimating lens  409  that collimates light from the light source  410  and a slidable mirror  411  that can be alternatively positioned into and out of the beam path of collimated light from the collimating lens  409 . When the slidable mirror  411  is positioned within the beam path of collimated light from the collimating lens  409 , the slidable mirror directs the collimated light to a fiber optic coupling  413  and into a fiber optic delivery cable  417 . When the slidable mirror  411  is positioned out of the beam path of collimated light from the collimating lens  409 , the collimated light is directed to a condensing lens  419  that focuses the light into a fiber optic cable  421  that is coupled to an illumination probe  423  used for delivery of purely illumination light. 
     The fiber optic delivery cable  417  delivers the illumination light from the illumination module to a collimating lens  425  in the laser light multiplexing module  403 . The collimating lens  425  collimates the illumination light and directs the collimated light to a beamsplitter  427 . Also, the laser source  405  directs substantially collimated (i.e., substantially collimated due to the substantially point-source nature of the laser light from the laser light source  405 ) to the beamsplitter  427 . The beamsplitter  427  is configured to transmit a portion of the light spectrum that corresponds to the wavelengths emitted by the laser source (e.g., red and green laser light) and configured to reflect a remaining portion of the light spectrum. More specifically, the beamsplitter  427  can be configured to both reflect laser aiming and treatment beams from the laser source  405  and transmit the illumination light from the collimating lens  425 . In this configuration the beamsplitter  427  effectively multiplexes laser light from the laser source  405  and collimated illumination light from the illumination light source  410 . The multiplexed light beam falls incident on a linear slide  450  that alternatively positions a DOE into the beam path to create a multi-spot pattern of laser light beams within the illumination light. Also, the laser light multiplexing module  403  includes a condensing lens  429  to focus the multiplexed light beam onto an interface  490  of the terminal end of the multi-core optical fiber cable  430  for delivery to surgical hand piece  415 . 
     In some cases, the light multiplexing components  402 ,  402 ′ and/or the laser light multiplexing module  403  are also integrated into a surgical console that include means for controlling aspects of a surgical procedure. For example, the light multiplexing components  402 ,  402 ′ and/or the laser light multiplexing module  403  can be integrated within a surgical console configured for use in vitreoretinal surgery that can power and control vitrectomy probes, can integrate pressurized infusion delivery and intraocular pressure compensation, can provide surgical illumination, etc. Also, in some cases, the light multiplexing components  402 ,  402 ′ and/or the laser light multiplexing module  403  are a stand-alone modules that can be used alongside a surgical console. 
     As mentioned above, a condensing lens can be selected to precisely focus the multiplexed light onto an interface of the terminal end of the multi-core optical fiber cable such that an illumination beam and laser aiming/treatment beams are propagated down an entire length of the multi-core optical fiber cable and into a surgical hand probe. More specifically, the condensing lens can be selected such that resulting light cones of light from the illumination beam and laser aiming/treatment beams have an acceptance angle and a numerical aperture (NA) to interface with the various fiber core and cladding materials used in the multi-core optical fiber cable such that the illumination beam and the laser aiming/treatment beams are propagated down the appropriate core fibers the entire length of the multi-core optical fiber cable. 
       FIG. 5A  illustrates the top view of a proximal end of a multi-core optical fiber cable  530  according to some embodiments of the present disclosure. The multi-core fiber cable  530  can include four inner core fibers  505  with a relatively small-diameter and a relatively small NA inside of an outer core fiber  510  having a relatively large diameter and a relatively large NA. The outer core fiber  510  can be contained within an outer-core cladding  515  with refractive index (n clad1 ) and the inner core fibers  505  can be contained within an inner-core cladding  520  with refractive index (n clad2 ). Also, the outer core  510  has a core diameter (d core2 ) and the inner cores  505  can have a core diameter (d core1 ). 
       FIG. 5B  illustrates a side view of the interface of a plurality of light cones  535 ,  540 ,  545  onto a terminal end of a multi-core optical fiber cable  530  according to some embodiments of the present disclosure. The multi-core optical fiber cable  530  in  FIG. 5B  shows the outer core fiber  510  and two of the inner core fibers  505 . For the sake of image clarity, the outer-core cladding  515  and the inner-core cladding  520  is not depicted in  FIG. 5B . Also represented are a wide-angle portion of the illumination light cone  535 , a narrow-angle portion of the illumination light cone  540 , and the laser light cone  545 . The selection of the condensing lens is related to the half-angle of each of the light cones. Therefore, selecting a condensing lens can involve selecting a condensing lens based on the NA of the light, the acceptance angle of the light cones, and the refractive indices of the materials of the outer core fiber  510 , the outer-core cladding  515 , the inner core fibers  505 , and the inner-core cladding  520 . 
     The condensing lens is designed to focus laser light down onto the multi-core fiber interface with the desired beam NA. The refractive indices of the inner core fibers  505  and inner cladding-core claddings  520  are selected according to an NA calculation (shown below) so that the NA of the inner cores is equal to or greater than the beam NA, thereby ensuring confinement of the beams within the inner core regions as they propagate down the lengths of the inner core fibers  505 . 
     Referring again to  FIG. 5A , a refractive index (n core2 ) of the outer core fiber  510  is greater than a refractive index (n clad2 ) of the outer-core cladding  515 . Also, a refractive index (n core1 ) of each of the inner cores fibers  505  is greater than a refractive index (n clad1 ) of the inner-core cladding  520 . Further, the refractive index (n core1 ) of each or the inner cores fibers  505  is larger than the refractive index (n clad1 ) of the outer-core cladding  515 . 
     The numerical aperture (NA 2 ) for the outer core fiber  510  and the outer-core cladding  515  can be calculated as: 
       NA 2 =√{square root over (( n   core2 ) 2 −( n   clad2 ) 2 )}
 
     Likewise, the numerical aperture (NA 1 ) for the inner core fibers  505  and the inner-core cladding  520  can be calculated as: 
       NA 1 =√{square root over (( n   core1 ) 2 −( n   clad1 ) 2 )}
 
     In some embodiments of the present disclosure, the materials for the outer core fiber  510 , the outer-core cladding  515 , the inner core fibers  505 , and the inner-core cladding  520  are selected such that NA 2  is much larger than NA 1 . In a specific embodiment, the outer core can be an undoped fused silica with an index of substantially 1.46. 
     Also, in some embodiments, the red aiming laser beam has an NA of about 0.044 and the green treatment laser beam has an NA of about 0.0657. Therefore, as long as the numerical aperture (NA 1 ) for the inner core fiber  505  is larger than 0.0657, the red and green laser beams will remain confined within the inner cores  505  as they propagate down the probe. So, a silica fiber with an NA of 0.22 used for the outer core  510  may confine the laser beams. 
     Also, the illumination light can have an NA of around 0.63 and the core diameter can be configured to under-fill or match d core2 . The numerical aperture (NA 2 ) for the outer core fiber  510  and the outer-core cladding  515  can be designed to have a fiber NA≥0.63, e.g. a borosilicate fiber construction. 
     When the illumination beam etendue is greater than outer core  510  etendue, then coupling efficiency into outer core  510  is less than one hundred percent regardless of condenser lens focal length choice. However, if the illumination beam etendue (which is the product of the illumination beam angular width and spot width) is less than the outer core  510  etendue, then one hundred percent coupling efficiency (neglecting Fresnel reflection losses) can occur if the condensing lens focus is designed correctly. If the condensing lens has too short of a focus, the converging beam may have an NA greater than core  510  NA, and coupling efficiency may be degraded. If the condensing lens has too long of a focal length, then the focused beam diameter may be larger than the  510  diameter, and coupling efficiency may be degraded. However if the condensing lens focal length is adjusted so that beam NA is less than or equal to the fiber NA, and the beam diameter is less than or equal to the fiber core diameter, then one hundred percent or near one hundred percent coupling efficiency can occur. 
     Therefore, the illumination beam may both spatially and angularly underfill the outer core  510 , which will permit spatial and angular misalignments without a loss of coupling efficiency. Also, since the illumination beam NA is &gt;&gt;NA1, off-axis rays can frequently pass in and out of the inner cores  505  and inner core cladding  520  as the rays propagate down the length of the multi-core optical fiber cable  530 . 
       FIG. 5C  illustrates the cut-away view of a multi-core optical fiber cable  550  according to some embodiments of the present disclosure. The multi-core fiber cable  550  includes four fused silica inner core fibers  505  with a 75 micrometer diameter and a numerical aperture (NA) of 0.22 inside of a non-doped fused silica outer core fiber  510  having a 300 micrometer diameter and an NA of 0.47. The outer core fiber  510  can be contained within low-index polymer cladding  515  having a 25 micrometer thickness and the inner core fibers  505  can be contained within fluorine-doped fused silica inner-core cladding  520  having a 15 micrometer thickness. The multi-core optical fiber cable  550  can be further contained in an Ethylene Tetrafluoroethylene (ETFE) coating  575 . 
     The four fused silica inner core fibers  505  have a refractive index of 1.46 at 532 nanometers. The non-doped fused silica outer core fiber  510  have a refractive index of 1.46 at 532 nanometers. The fluorine-doped fused silica inner-core cladding  520  can have a refractive index of 1.4433 at 532 nanometers. The low-index polymer cladding  515  can have a refractive index of 1.38228 at 532 nanometers. 
       FIG. 5D  illustrates a proximal, interface end of the multi-core optical fiber cable with a red laser aiming beam spot  506  and a green laser treatment beam spot  507  lining up with the inner cores  505  and the illumination light beam spot  508  lining up with the outer core  510 .  FIG. 5E  illustrates the distal end of the multi-core optical fiber cable with all three beams spread out to totally spatially fill their respective cores. FIGS.  5 F- 5 L illustrate the propagation of the multiplexed light through the multi-core optical fiber cable. 
       FIG. 5F  illustrates a proximal, interface end of the multi-core optical fiber cable with a red laser aiming beam spot  506  and a green laser treatment beam spot  507  lining up with the inner cores  505 .  FIG. 5G  illustrates two light cones from the multi-spot pattern of laser light (with the multiplexed illumination light emitted for image clarity) propagating down the lengths of a multi-core optical fiber cable.  FIG. 5H  illustrates the laser beams spread out to totally spatially fill the inner cores  505 . Similarly,  FIG. 5I  illustrates the distal end of the multi-core optical fiber cable with the laser beams spread out to totally spatially fill the inner cores  505 . 
       FIG. 5J  illustrates a proximal, interface end of the multi-core optical fiber cable with the illumination light spot lining up with the outer core  510 .  FIG. 5K  illustrates a light cone of the illumination light (with the multiplexed multi-spot pattern of laser light beams emitted for image clarity), with the light cone including a narrow half-angle portion of the light cone and a wide half-angle portion. The narrow half-angle portion of the light cone propagates the lengths of the outer cores  510 , but is excluded from the inner cores  505 . The wide half-angle portion of the illumination light cone fills the length of the outer core  510  and the inner cores  505 . 
       FIG. 5L  illustrates the illumination beam spread out to totally spatially fill the outer core  510 . Similarly,  FIG. 5M  illustrates the distal end of the multi-core optical fiber cable with the illumination beam spread across the outer cores  510  and the inner cores  505 . 
       FIG. 5N  illustrates the cut-away view of another multi-core optical fiber cable  580  according to some embodiments of the present technology. The multi-core fiber cable  580  includes four germanium-doped silica inner core fibers  585  with a 75 micrometer diameter and a numerical aperture (NA) of 0.22 inside of a non-doped fused silica outer core fiber  590  having a 300 micrometer diameter and an NA of 0.47. The outer core fiber  590  can be contained within low-index polymer cladding  595  having a 25 micrometer thickness. The multi-core optical fiber cable  580  can be further contained in an Ethylene Tetrafluoroethylene (ETFE) coating  576 . 
     The four germanium-doped silica inner core fibers  585  have a refractive index of substantially 1.47648 at 532 nanometers. The non-doped fused silica outer core fiber  590  have a refractive index of 1.46 at 532 nanometers. The low-index polymer cladding  595  can have a refractive index of 1.38228 at 532 nanometers. 
     While specific geometries of the multi-core optical fiber cable are shown explicitly herein, those with ordinary skill in the art having the benefit of the present disclosure will readily appreciate that a wide variety of configurations for the multi-core optical fiber cable are possible. In the configuration shown in  FIGS. 5A-5N , the white illumination spot at the distal end of the multi-core optical fiber is somewhat larger than the 2×2 array of laser spots. In some cases, this geometry is desired, because it provides illumination into both the retinal treatment target area as well as some surrounding retina and because the illumination spot small enough to keep the white light fairly concentrated. Also, the geometry enables adequate white irradiance at the retina with a relatively small core diameter fiber. Furthermore, as explained above, the intensities of the white illumination and the laser aiming beams can be adjusted (e.g., at the Illumination Light Source and Surgical Laser System, respectively) to provide the right amount of laser aiming beam contrast against the white while providing enough white illumination to easily see the retina. 
     In some embodiments of the present technology, the distal end of the multi-core optical fiber cable terminates within a tip of a surgical hand probe that is inserted into a patient&#39;s eye. The tip of the surgical hand probe can also include a lens to image the multiplexed beams onto patient anatomy, e.g. the retina. 
       FIG. 6A  illustrates an open side view of a tip  605  of a surgical hand probe according to some embodiments of the present disclosure. The probe tip  605  can comprise a cannula  635  (e.g. a stainless steel cannula) with a cannula distal end  630  and the probe tip containing the multi-core optical fiber  610  and a lens  615 . The lens  615  can be a graded-index (GRIN) lens and an air gap  625  can be left open between the GRIN lens  615  and the distal end of the multi-core optical fiber  610 . The air gap  625  can be sized such that the light emitted from the multi-core optical fiber  610  experiences an amount of spread before falling incident on the GRIN lens  615  and such that the GRIN lens  615  images the light onto the patient anatomy. 
     In some cases, no air gap is allowed between the distal end of the multi-core optical fiber  610  and the proximal end of the lens  615 . Here, the multi-core optical fiber  610  and lens  615  are substantially butted up against one other with positive pressure to avoid air-gap tolerance concerns, allowing less chance for peripheral off-axis rays to travel far enough off axis to reflect off of the cylindrical side wall of the GRIN lens. However, using a conventional lens instead of the GRIN lens involves an air gap between the multi-core optical fiber  610  and lens  615  to focus the light properly. 
     In some cases, the lens  615  is secured within the probe tip  605  with an optical adhesive  620 . As shown in  FIG. 6A , a multi-spot pattern of green, 532 nm laser light is projected retinal tissue located 4 millimeters from the cannula distal end  630 . 
       FIG. 6B  illustrates an open side view of another tip  640  of a surgical hand probe according to some embodiments of the present disclosure. Again, the probe tip  640  can comprise a cannula  645  with a cannula distal end  650  and the probe tip containing the multi-core optical fiber  655  and a lens  660 . The lens  660  illustrated in  FIG. 6B  is a Plano-convex glass lens. Also, the Plano-convex lens  660  is secured in the cannula  635  by a retaining feature  665 . Again, an air gap  670  can be sized such that the light emitted from the multi-core optical fiber  655  experiences an amount of spread before falling incident on the Plano-convex lens  660  and such that the Plano-convex lens  660  images the light onto the patient anatomy. 
       FIG. 7  illustrates a method  700  of creating an image of a multiplexed beam of multi-spot pattern of laser light beams and illumination light in accordance with a particular embodiment of the present disclosure. The method involves: selecting materials for a multi-core optical fiber cable to ensure confinement of the beams within the various core regions as they propagate down the lengths fiber cable at step  705 , as explained above. The method  700  also involves determining a numerical aperture of laser light beams from a laser source and a numerical aperture of an illumination light beam from an illumination light source at step  725  and selecting a condensing lens to focus the multiplexed multi-spot pattern of laser light beams and illumination beam onto an interface plane of the multi-core optical fiber cable at step  730 . 
     Next, the method  700  involves multiplexing a multi-spot pattern of laser light beams with the illumination light beam at step  735 , focusing the multiplexed multi-spot pattern of laser light beams and illumination beam onto an interface plane of the multi-core optical fiber cable at step  740 , and directing the multiplexed beam of multi-spot pattern of laser light beams and illumination light through a lens in the surgical handpiece at step  745 . 
     As explained above, a wide variety of configurations for the multi-core optical fiber cable are possible. For example, an incoherent white light illumination light source can be replaced with a white laser system (e.g., a supercontinuum laser system). In this case, the etendue of the white laser beam is small enough that it is less than the nanofiber etendue and can be efficiently coupled into the nanofiber, such that a multi-core optical fiber cable as described above can be used to deliver multiplexed laser aiming and treatment beams and white laser illumination. 
       FIGS. 8A-8D  illustrate another example of a system for multiplexing laser aiming and treatment beams and illumination light.  FIG. 8A  illustrates an end view of a multi-lumen tubing  800  for delivering multiplexed laser aiming and treatment beams and a laser illumination light beam. The multi-lumen tubing  800  includes a central nanofiber  805  and an array of glass laser fibers  810  contained within the multi-lumen tubing  800 . The central nanofiber  805  can be a large NA fiber for carrying a white laser beam and the glass laser fibers  810  can be small diameter, small NA glass fibers for carrying laser aiming and treatment beams (e.g. red aiming beams and green treatment beams). In some cases, the central nanofiber  805  can be enclosed within a tiny-diameter, rigid, cylindrical or square, black absorptive or reflective cannula for structural support, and can optionally be attached a focusing lens (described below) for structural support as well. 
     As shown in  FIGS. 8B-8C , each of the laser aiming beams  806  and laser treatment beams  807  as well as the laser illumination light beam  808  will spatially underfill their respective fiber cores at the proximal end ( FIG. 8B ), but will totally fill their cores at the distal end ( FIG. 8C ). In this case, in order to have the white laser illumination beam spatially larger than the multi-spot laser beam pattern at the retina, it is necessary to extend the distal end  820  of the nanofiber  815  past the distal end  825  of the array of glass fibers  810  in the multi-lumen tubing  800  until the distal end  820  of the nanofiber  815  is at or near a proximal end of a focusing lens  830  (e.g., a plano-convex lens), as shown in  FIG. 8D . 
     The above disclosed subject matter is to be considered illustrative, and not restrictive, and the appended claims are intended to cover all such modifications, enhancements, and other embodiments which fall within the true spirit and scope of the present disclosure. Thus, to the maximum extent allowed by law, the scope of the present disclosure is to be determined by the broadest permissible interpretation of the following claims and their equivalents, and shall not be restricted or limited by the foregoing detailed description.