Abstract:
A method and apparatus for collecting and projecting light into a specified target illuminance. A lens may be mounted or otherwise paired to a carrier to form a lens/carrier combination, which may then be mounted to a printed circuit board assembly (PCBA) containing a light emitting diode (LED). The lens/carrier combination may establish an optimum optical relationship between the LED and the lens, such that a predetermined photometric distribution of the LED is collected by the lens, while the remaining photometric distribution of the LED is rejected by the carrier. The lens may include a first pair of opposing surfaces forming a first focus and a second pair of opposing surfaces forming a second focus. The first and second foci may cause light to be subtended into one or more of collimated light focused light, diffused light, and shifted light. The carrier may include an obstruction extending toward the PCBA.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention generally relates to lighting systems, and more particularly to light collection and projection systems. 
       BACKGROUND 
       [0002]    Light emitting diodes (LEDs) have been utilized since about the 1960s. However, for the first few decades of use, the relatively low light output and narrow range of colored illumination limited the LED utilization role to specialized applications (e.g., indicator lamps). As light output improved, LED utilization within other lighting systems, such as within LED “EXIT” signs and LED traffic signals, began to increase. Over the last several years, the white light output capacity of LEDs has more than tripled, thereby allowing the LED to become the lighting solution of choice for a wide range of lighting solutions. 
         [0003]    LEDs exhibit significantly optimized characteristics for use in lighting fixtures, such as source efficacy, optical control and extremely long operating life, which make them excellent choices for general lighting applications. LED efficiencies, for example, may provide light output magnitudes that may exceed 100 lumens per watt of power dissipation. Energy savings may, therefore, be realized when utilizing LED-based lighting systems as compared to the energy usage of, for example, incandescent, halogen, compact fluorescent and mercury lamp lighting systems. As per an example, an LED-based lighting fixture may utilize a small percentage (e.g., 10-15%) of the power utilized by an incandescent bulb, but may still produce an equivalent magnitude of light. 
         [0004]    LEDs may be mounted to a printed circuit board (PCB), which may include conductive regions (e.g., conductive pads) and associated control circuitry. The LED control terminals (e.g., the anode and cathode terminals of the LEDs) may be interconnected via the conductive pads, such that power supply and bias control signals may be applied to transition the LEDs between conductive and non-conductive states, thereby illuminating the LEDs on command. 
         [0005]    The photometric distribution of a forward-biased LED may produce an omnidirectional pattern of light (e.g., a 180 degree spread of light emanating in all directions from a surface of the PCB upon which the LED is mounted). In order to modify such an omnidirectional photometric distribution, a plastic dome (e.g., an injection molded acrylic plastic cover) may be placed over the LED. In so doing, for example, the plastic dome may modify the photometric distribution pattern from that of an omnidirectional pattern to one of a non-omnidirectional pattern (e.g., a 120 degree spread of light emanating from a surface of the PCB). A lens may be mounted forward of the LED to further control the photometric distribution of the LED. 
         [0006]    A system of one or more LEDs and associated lenses may, for example, be implemented within an LED-based lighting system. Each LED of such a system, however, may exhibit a photometric distribution such that the light emitted by one LED may be projected into one or more lenses that may be associated with one or more adjacent LEDs. In such an instance, for example, one lens may receive the light generated by one or more adjacent LEDs (e.g., interference light), which may adversely affect the pattern of light projected by the LED-based lighting system. 
         [0007]    Efforts continue, therefore, to develop a multiple LED lighting system that reduces adverse interference light. 
       SUMMARY 
       [0008]    To overcome limitations in the prior art, and to overcome other limitations that will become apparent upon reading and understanding the present specification, various embodiments of the present invention disclose methods and apparatus for the collection and projection of light in an LED-based lighting system. 
         [0009]    In accordance with one embodiment of the invention, an LED-based lighting system comprises a PCBA having an LED, a carrier coupled to the PCBA, and a lens. The carrier includes an aperture in a geometric relationship with the LED. The lens is configured to subtend light received from the LED through the aperture. The lens includes a first set of opposing surfaces forming a first focus and a second set of opposing surfaces forming a second focus. 
         [0010]    In accordance with another embodiment of the invention, an LED-based lighting system comprises a PCBA having first and second LEDs, a carrier coupled to the PCBA, and a lens structure with at least one obstruction. The carrier includes first and second apertures. The lens includes first and second lenses. The lens structure is coupled to the carrier to receive light from the first and second LEDs through the first and second apertures, respectively. The at least one obstruction extends from the carrier to prevent light from the first LED from entering the second lens and to prevent light from the second LED from entering the first lens. 
         [0011]    In accordance with another embodiment of the invention, a method comprises emitting light from an LED in an effective span of emission. The method further includes passing a first portion of the effective span through a first discrete region of a lens to produce a first subtended span of light. The method further includes passing a second portion of the effective span through a second discrete region of the lens to produce a second subtended span of light. The method further includes preventing substantially all remaining light of the effective span of emission from passing through the lens. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]    Various aspects and advantages of the invention will become apparent upon review of the following detailed description and upon reference to the drawings in which: 
           [0013]      FIG. 1  illustrates an LED-based lighting fixture in accordance with one embodiment of the present invention; 
           [0014]      FIG. 2  illustrates a light collection and projection system in accordance with one embodiment of the present invention; 
           [0015]      FIG. 3  illustrates an alternate light collection and projection system in accordance with one embodiment of the present invention; 
           [0016]      FIG. 4  illustrates side and plan views of a light collection and projection system in accordance with one embodiment of the present invention; 
           [0017]      FIG. 5  illustrates a photometric diagram of a side view of a light collection and projection system in accordance with one embodiment of the present invention; 
           [0018]      FIG. 6  illustrates light projection diagrams of various light collection and projection systems in accordance with various embodiments of the present invention; and 
           [0019]      FIG. 7  illustrates geometric relationships between an LED and an associated carrier and resulting light projections in accordance with various embodiments of the present invention; 
           [0020]      FIG. 8  illustrates an LED-based lighting fixture in accordance with another embodiment of the present invention; 
           [0021]      FIG. 9  illustrates a light collection and projection system in accordance with another embodiment of the present invention; 
           [0022]      FIG. 10  illustrates a light collection and projection system in accordance with another embodiment of the present invention; 
           [0023]      FIG. 11  illustrates a cross-sectional view of the light collection and projection system of  FIG. 10 ; 
           [0024]      FIG. 12A  illustrates a back side view of a lens structure for attachment with a front side of a carrier; 
           [0025]      FIG. 12B  illustrates a front side view of a carrier for attachment with a back side of a lens structure; 
           [0026]      FIG. 13  illustrates a side view of a lens structure; 
           [0027]      FIG. 14  illustrates a photometric diagram of a side cross-sectional view of a light collection and projection system in accordance with another embodiment of the present invention; 
           [0028]      FIG. 15  illustrates a photometric diagram of a top cross-sectional view of a light collection and projection system in accordance with another embodiment of the present invention; 
           [0029]      FIG. 16  illustrates a cross-sectional view of a segment of the light collection and projection system of  FIG. 10 . 
       
    
    
     DETAILED DESCRIPTION 
       [0030]    Generally, the various embodiments of the present invention are applied to a light emitting diode (LED) based lighting system that may contain one or more LEDs and one or more associated lenses. The LEDs may be mounted to a PCB having control and bias circuitry that allows the LEDs to be illuminated on command. A lens may be mounted forward of an associated LED, so as to control a pattern of light that may be projected by each LED of the lighting system. 
         [0031]    A carrier may be used to facilitate the mounting of the lens forward of its associated LED. For example, a carrier may exhibit a locking mechanism (e.g., a friction-based, male locking mechanism) that may be compatible with a corresponding locking mechanism (e.g., a friction-based, female locking mechanism) of the corresponding lens. Once interlocked (e.g., once the lens is “snapped” into place within the carrier), the lens may be secured within the carrier to form a carrier/lens combination, such that the position of the lens relative to the orientation of the carrier may create an optimal geometric relationship between the lens and the carrier. Alternately, for example, the carrier and lens may not necessarily include interlocking mechanisms. 
         [0032]    The carrier may, for example, include one or more extrusions (e.g., legs) having indexing features (e.g., feet) that may allow the carrier/lens combination to be secured to a PCB at a particular orientation as defined by the indexing features. The PCB may, for example, include corresponding indexing features (e.g., holes) that may be configured to accept the indexing features of the carrier, such that once the carrier/lens combination engages the indexing features of the PCB, a position of the carrier/lens combination relative to the orientation of the PCB maintains an optimal geometric relationship between the LED mounted to the PCB and its corresponding carrier/lens combination. 
         [0033]    The carrier/lens combination may couple a predetermined portion of the photometric distribution of its corresponding LED, such that the predetermined portion may be allowed to be projected into the corresponding carrier/lens combination, while the remaining portion of the photometric distribution may be disallowed from entering the corresponding carrier/lens combination. Furthermore, the remaining portion of the photometric distribution of an LED that may be disallowed from entering the corresponding carrier/lens combination, may also be prevented from entering the carrier/lens combinations associated with neighboring LEDs, if any, in the LED-based lighting system. 
         [0034]    Each carrier of each carrier/lens combination may be configured with a bowl structure that is narrow at one end and wider at the other end. The narrow end of each carrier may be configured with an aperture such that once the carrier/lens combination engages the PCB, the aperture may be positioned over the corresponding LED to establish a geometric relationship between the LED and the aperture (e.g., an optimal separation distance between the aperture and the LED). Furthermore, the aperture may be beveled, or flanged, so as to present an aperture having an inner wall that is not perpendicular to an optical axis of its corresponding LED, but is rather angled with respect to an optical axis of its corresponding LED. Accordingly, for example, light emanating from the LED at an angle greater than the angle formed by the inside wall of the aperture may be projected onto its corresponding lens, while light emanating from the LED at an angle less than the angle formed by the inside wall of the aperture may be prohibited from projecting onto its corresponding lens. 
         [0035]    The bowl structure of each carrier may be configured to reduce, or eliminate, reflections of light that may be incident onto the bowl structure. For example, the bowl structure may exhibit a surface that provides hard optical angles (e.g., a stair-stepped surface or a rounded stair-stepped surface) such that any light incident on the bowl structure may be reflected, if at all, away from the corresponding lens. In addition, the bowl structure may exhibit a non-reflective color (e.g., black) so as to be substantially non-reflective of any light that may be incident on the bowl structure. Further, the bowl structure may exhibit a non-reflective texture (e.g., a coarse texture) so as to be substantially non-reflective of any light that may be incident on the bowl structure. 
         [0036]    An optical system that may include a PCB, an LED, and a carrier/lens combination may combine to substantially project a portion of the light emitted from the LED onto its corresponding lens, while substantially rejecting all other light that may otherwise be incident on the corresponding lens (e.g., reflected light from the corresponding LED or incident light from neighboring LEDs). Accordingly, the light projected by the LED-based lighting system may exhibit a specified target illuminance (e.g., a spot beam pattern), while rejecting substantially all other light that might otherwise exist outside of the target illuminance (e.g., spill light outside of the spot beam pattern). 
         [0037]    The lens of each carrier/lens combination may exhibit various configurations. For example, the lens may exhibit two convex surfaces (e.g., a biconvex configuration), or may exhibit a flat surface on one side of the lens and a convex surface on the other side of the lens (e.g., a plano-convex configuration). The lens may, for example, exhibit two convex surfaces, where the radius of curvature of one convex surface may be different than the radius of curvature of the other convex surface. The lens may, for example, exhibit two convex surfaces, where the radius of curvature of one convex surface may be the same as the radius of curvature of the other convex surface (e.g., a equi-convex configuration). The lens may, for example, exhibit an optical surface that may be broken up into narrow, concentric rings (e.g., a Fresnel lens configuration), such that the lens may be manufactured to be thinner and, therefore, lighter than the convex or plano-convex configurations. 
         [0038]    Once the photometric distribution of an LED of an LED-based lighting system has been controlled into an initial target illuminance (e.g., a spot beam pattern), other optical treatments may be applied to effect a subsequent target illuminance that may be produced from the initial target illuminance. For example, a supplemental optic (e.g., a diffuser) may be used to spread the initial target illuminance into a wider beam pattern that may exhibit attributes that may be beneficial in certain applications. For example, a diffuser may be applied to spread the initial target illuminance into a pattern that may be compliant with standards as promulgated by the U.S. Department of Transportation or the Economic Commission for Europe. An additional diffuser may be applied, for example, whereby the initial target illuminance may be spread by a first diffuser and spread again by a second diffuser (e.g., a first diffuser may spread light along a horizontal axis and a second diffuser may spread the horizontally spread light along a vertical axis). 
         [0039]    Turning to  FIG. 1 , an exemplary LED-based lighting fixture  100  is illustrated, which may include body portion  108  and heat sink portion  110 . Body portion  108  may, for example, include one or more lenses  106 , a plate (e.g., transparent plate  104 ), and bezel  102 . LED-based lighting fixture  100  may further include one or more carriers (not shown) which may provide a retaining mechanism for lenses  106 . LED-based lighting fixture  100  may further include a PCB (not shown) which may include one or more LEDs (not shown), associated LED bias and control circuitry (not shown) and mechanical indexing (not shown) to retain lenses  106  and associated carriers. Transparent plate  104  may be held into place by bezel  102  and associated bezel hardware  112 . In addition, transparent plate  104  may be in mechanical communication with extensions  114 , such that once bezel  102  is held in place by bezel hardware  112 , transparent plate  104  may contact extensions  114  to press lenses  106  and their associated carriers into the corresponding mechanical indexing of the PCB. Accordingly, for example, the optical system within body portion  108  may be held in place via plate  104 , bezel  102  and bezel hardware  112  so as to preserve the optimal geometric relationship between the LEDs and associated lenses  106 . Alternately, for example, the optical system within body portion  108  may be held in place by other mechanical means (e.g., screws). 
         [0040]    A side view of LED-based lighting fixture  150  is illustrated, which exemplifies heat sink fins  152  and their connection to body portion  156 . Accordingly, for example, heat sink fins  152  may be in thermal communication with body portion  156  along interface  154 , such that heat generated within body portion  156  may be transferred to heat sink fins  152  along interface  154 , thereby reducing the temperature of body portion  156  and the electronic components (e.g., LEDs) mounted therein. For example, body portion  156  may contain a PCB (not shown) with LEDs mounted thereon (not shown) that may be in thermal communication with heat sink fins  152  via body portion  156  along interface  154 . As the LEDs are illuminated, power may be dissipated by the LEDs into heat, which may then be transferred to heat sink fins  152 . Heat sink fins  152  may then conduct the heat into the atmosphere that surrounds heat sink fins  152  thereby reducing the temperature of body portion  156  and reducing the temperature of the LEDs mounted therein. 
         [0041]    It should be noted that virtually any light fixture may accommodate an LED-based lighting system having one or more LEDs. For example, single-LED light fixtures, single-row light bars, double-row lights bars, and matrix light fixtures, to name only a few, may accommodate the light collection and projection systems provided herein. 
         [0042]    Turning to  FIG. 2 , an exploded view of light collection and projection system  200  is exemplified, which may include PCB  202  with one or more LEDs (e.g., LEDs  204 - 210 ) and associated bias and control circuitry (not shown) mounted thereon. Light collection and projection system  200  may further include carrier  212  that may include one or more bowl structures (e.g., bowl portion  230 ) and a lens structure  214  that may include one or more lenses  232 . PCB  202  may, for example, include mechanical indexing features (e.g., holes  222 ) that may be associated with corresponding mechanical indexing features (e.g., feet  228 ) of extension portions (e.g., legs  226 ) of carrier  212 . Once engaged, the mechanical indexing features (e.g., holes  222  and feet  228 ) of PCB  202  and carrier  212 , respectively, may create an optimized geometric relationship between LEDs  204 - 210  and the corresponding apertures  224  of carrier  212 . 
         [0043]    Such an optimized geometric relationship may, for example, include an optimized separation distance (e.g., between approximately 0.03 and 0.04 inches) between a bottom portion of carrier  212  (e.g., rearward surface  1622  of  FIG. 16 ) and a top portion of LEDs  204 - 210  (e.g., forward portion  1605  of  FIG. 16 ) as may be facilitated by extension portions (e.g., legs  226 ) of carrier  212 . Such an optimized separation distance may, for example, facilitate a predetermined portion of the photometric distribution of LEDs  204 - 210  to be collected by the corresponding apertures  224  of carrier  212 . In addition, such an optimized separation distance may, for example, facilitate a predetermined portion of the photometric distribution of LEDs  204 - 210  to be prohibited from being collected by the corresponding apertures  224  of carrier  212 . 
         [0044]    Carrier  212  may, for example, include bowl portion  230 , which may include a narrow end  234  (e.g., the end of bowl portion  230  that includes aperture  224 ) and a wide end  235  (e.g., the end of bowl portion  230  that is opposite the narrow end of aperture  224 ). Bowl portion  230  may include surfaces  236  (e.g., the four inner walls of bowl portion  230 ) that may exhibit hard optical angles (e.g., a stair-stepped surface) such that any light that may be incident on the four inner walls of bowl portion  230  may be reflected, if at all, away from corresponding lens  232 . 
         [0045]    It should be noted that manufacturing techniques may somewhat preclude the formation of hard optical angles. In such an instance, for example, the corners of the stair-stepped structure of the inner walls of bowl portion  230  may exhibit a nominal radius of curvature (e.g., 1/32 of an inch). In other words, the corners of the stair-stepped structure of the inner walls of bowl portion  230  may be somewhat rounded. 
         [0046]    In addition, bowl portion  230  may exhibit a non-reflective color (e.g., black) so as to be substantially non-reflective of any light that may be incident on bowl portion  230 . Further, bowl portion  230  may exhibit a non-reflective texture (e.g., a coarse texture) so as to be substantially non-reflective of any light that may be incident on bowl portion  230 . 
         [0047]    Bowl portion  230  may include one or more concave recesses  234  that may exist at the wide end  235  of bowl portion  230 . Concave recesses  234  may, for example, be configured to receive respective bottom portions (e.g., bottom portion  437  of  FIG. 4 ) of lens  232  after carrier  212  and lens structure  214  are mated to one another to form a carrier/lens assembly. Lens  232  may, for example, exhibit a bi-convex configuration, such that the radius of curvature of a bottom portion (e.g., bottom portion  437  of  FIG. 4 ) of lens  232  matches the radius of curvature of concave recesses  234 . 
         [0048]    Carrier  212  may include one or more locking mechanisms (e.g., friction-based male locking mechanisms  218 ) and lens structure  214  may include one or more corresponding locking mechanisms (e.g., friction-based female locking mechanisms  216 ). Accordingly, for example, once carrier  212  and lens structure  214  are mated to one another to form the carrier/lens assembly, friction-based male locking mechanisms  218  and corresponding friction-based female locking mechanisms  216  may engage each other to lock (e.g., temporarily lock) the carrier/lens assembly in place. 
         [0049]    Lens structure  214  may include one or more extensions  220 . Extensions  220  may, for example, engage portions of an LED-based lighting fixture (e.g., transparent plate  104  of the LED-based lighting fixture  100 ), thereby imposing a pressure on extensions  220  along axis  236  to press carrier  212  and lens structure  214  against PCB  202 . Accordingly, for example, light collection and projection system  200  may maintain optimized geometric relationships while being operational within the LED-based lighting fixture. 
         [0050]    It should be noted that lens structure  214  may not necessarily be a bi-convex structure as shown. Instead, for example, lens structure  214  may include a Fresnel lens, which may exhibit an optical surface that may be broken up into narrow, concentric rings. Other alternatives that may be used as lens structure  214  may include plano-convex configurations and equi-convex configurations to name only a few. 
         [0051]    Turning to  FIG. 3 , an exploded view of light collection and projection system  300  is exemplified, which may include a collection and projection system (e.g., two-LED collection and projection system  302 ) and diffuser  304 . Diffuser  304  may, for example, also function as a plate of an LED-based lighting fixture (e.g., transparent plate  104  of  FIG. 1 ). Conversely, the LED-based lighting fixture may include a separate plate (not shown), whereby diffuser  304  may be temporarily or permanently attached to the plate. 
         [0052]    As an example, diffuser  304  may exhibit scalloped structure  306 , where each scallop may exhibit an arc (e.g., a 45 degree arc) that may run the entire width  312  of diffuser  304 . In operation, diffuser  304  may receive a controlled beam of light having a specified target illuminance (e.g., spot beam  308 ) as may be projected by LED-based lighting system  302 . Diffuser  304  may, for example, spread the light projected by spot beam  308  into diffused beam  310 , whereby spot beam  308  may be transformed into a secondary target illuminance that may conform to standards as promulgated, for example, by the Department of Transportation or the Economic Commission for Europe. In such an instance, for example, diffused beam  310  may be compatible for use as a head light in automotive applications. 
         [0053]    An additional diffuser (not shown) may be superimposed upon diffuser  304  to diffuse light along a different axis than light diffused by diffuser  304 . For example, the additional diffuser may exhibit a scalloped structure, where each scallop may exhibit an arc that may run the entire length  314  of the additional diffuser. In operation, the additional diffuser may receive a controlled beam of light having a specified target illuminance (e.g., diffused beam  310 ). The additional diffuser may, for example, spread diffused beam  310  into a different diffused beam, whereby diffused beam  310  may be transformed into a tertiary target illuminance (e.g., multiple directions of light at differing intensities). 
         [0054]    It should be noted that any types and/or combinations of diffusers may be utilized with light collection and projection system  302 . Bulk/die additive diffusers may be utilized, for example, whereby inks, dies or other light-absorbing chemicals may be added to the diffuser substrate to create a combination of intensity, reflection, refraction and/or diffraction. Holographic diffusers may, for example, include surface structures of various shapes to diffract light in accordance with a particular application. Volumetric diffusers may, for example, be utilized that suspend particles within the diffuser substrate to guide light through refraction in a controlled fashion. 
         [0055]    For example, two 20-degree diffusers superimposed on each other and aligned along the same axis may provide the same target illuminance of a single 45-degree diffuser. As per another example, two diffusers superimposed on each other and aligned along orthogonal axes may combine to form a symmetrical flood beam when diffusing a collected light source (e.g., spot beam  308 ). 
         [0056]    Turning to  FIG. 4 , various plan and side views of a light collection and projection system are exemplified. PCB  400 , for example, is illustrated in plan view  400 A to exemplify placement of LEDs  402  and  404  relative to one another. LED  402 , for example, may exhibit an orientation as shown and LED  404  may exhibit an orientation that is rotated with respect to LED  402 . As per an example, LED  404  may be rotated (e.g., rotated by 45 degrees) with respect to the orientation of LED  402 . 
         [0057]    Light collection and projection systems exhibiting a number of LEDs greater than two may exhibit similar LED orientations that may be dependent upon the specific number of LEDs being utilized. For example, a light collection and projection system utilizing three LEDs, may rotate the placement of each LED by 30 degrees with respect to one another. As per another example, a light collection and projection system utilizing four LEDs, may rotate the placement of each LED by 22.5 degrees with respect to one another. In general, the specific rotation exhibited by each LED may be calculated by equation (1) as: 
         [0000]        R= 90/ N,   (1)
 
         [0000]    where N is the number of LEDs utilized in a light collection and projection system and R is the rotation offset in degrees that may by exhibited by each LED. Accordingly, for example, a light collection and projection system utilizing six LEDs may exhibit LEDs that are rotated by 15 degrees with respect to one another. 
         [0058]    PCB  400  may, for example, utilize mechanical indexing features (e.g., holes  406 ) that may be configured to accept the mechanical indexing features (e.g., feet  454 ) of a component (e.g., carrier  456 ) to engage carrier  456  to PCB  400 . Carrier  456  may further be engaged to lens  458  to form a carrier/lens combination, whereby a locking mechanism (e.g., friction-based, male locking mechanism  460 ) may engage a corresponding locking mechanism (e.g., friction-based, female locking mechanism  462 ) to form carrier/lens combination  452 . 
         [0059]    Light collection and projection system  475  may include PCB  400  and carrier/lens combination  452 . As illustrated, one or more mechanical indexing features  406  may engage corresponding mechanical indexing features  454  of carrier/lens combination  452  to form light collection and projection system  475 . Light collection and projection system  475  may then be integrated within an LED-based lighting fixture (e.g., LED-based lighting fixture  100  of  FIG. 1 ). 
         [0060]    Turning to  FIG. 5 , a photometric diagram of a side view of a light collection and projection system is exemplified. Multiple LEDs (e.g., LEDs  504  and  506 ) may, for example, be mounted to PCB  502  along with bias and control circuitry (not shown) to illuminate LEDs  504  and  506  on command. The photometric distribution of LEDs  504  and  506  may, however, be such that light emitted from LED  504  may be received by lens  514  (e.g., interference light  524 ) and conversely, light emitted from LED  506  may be received by lens  512  (e.g., interference light  522 ). Accordingly, carrier  508  may be employed to block interference light  522  from entering lens  512  and carrier  510  may be employed to block interference light  524  from entering lens  514 . Carrier  508  may further be employed to mechanically engage lens  512  to maintain an optimal geometric relationship between lens  512  and LED  504  and carrier  510  may further be employed to mechanically engage lens  514  to maintain an optimal geometric relationship between lens  514  and LED  506 . 
         [0061]    Carrier  508  may, for example, exhibit aperture  538  having a flanged, or angled, portion to allow light emanated from LED  504  (e.g., light having spread  526 ) to be passed on to lens  512 . As can be seen, photometric distribution from LED  504  that extends outside of carrier  508  may not pass to lens  512 , nor may it pass to lens  514  due to the blocking operation of carrier  510 . Similarly, carrier  510  may, for example, exhibit aperture  540  having a flanged, or angled, portion to allow light emanated from LED  506  (e.g., light having spread  528 ) to be passed on to lens  514 . As can be seen, photometric distribution from LED  506  that extends outside of carrier  510  may not pass to lens  514 , nor may it pass to lens  512  due to the blocking operation of carrier  508 . 
         [0062]    Carrier  508  may, for example, exhibit hard optical angles (e.g., a stair-stepped surface having sharp corners or a stair-stepped surface having rounded corners) such that any light incident on the stair-stepped surface (e.g., light  530 ) may be reflected, if at all, away from lens  512 . In addition, carrier  508  may exhibit a non-reflective color (e.g., black) so as to further increase absorption of light  530 . Further, carrier  508  may exhibit a non-reflective texture (e.g., a coarse texture) so as to further increase absorption of light  530 . Similarly, carrier  510  may, for example, exhibit hard optical angles (e.g., a stair-stepped surface having sharp corners or a stair-stepped surface having rounded corners) such that any light incident on the stair-stepped surface (e.g., light  532 ) may be reflected, if at all, away from lens  514 . In addition, carrier  510  may exhibit a non-reflective color (e.g., black) so as to further increase absorption of light  532 . Further, carrier  510  may exhibit a non-reflective texture (e.g., a coarse texture) so as to further increase absorption of light  532 . 
         [0063]    Light emanated from lens  512  (e.g., light  534 ) may, therefore, result from only that light emitted by LED  504  that falls within the photometric distribution as defined by aperture  538  of carrier  508 . In addition, any light emitted by LED  506  is not permitted to enter lens  512  by virtue of carrier  508 . Similarly, light emanated from lens  514  (e.g., light  536 ) may, therefore, result from only that light emitted by LED  506  that falls within the photometric distribution as defined by aperture  540  of carrier  510 . In addition, any light emitted by LED  504  is not permitted to enter lens  514  by virtue of carrier  510 . 
         [0064]    Accordingly, for example, light emitted by each lens of an LED-based lighting system may be based almost entirely on the light emitted by the LED that is associated with that particular lens due to the shape, color, texture and other characteristics of the carrier that supports the lens. In so doing, a specified target illuminance (e.g., a spot beam pattern) may be provided by each lens of an LED-based lighting system that is substantially free from spill light or otherwise uncontrolled light. 
         [0065]    Turning to  FIG. 6 , light projection diagrams are exemplified. Light projection diagram  600  may, for example, represent the specified target illuminance delivered by an LED-based lighting system having multiple (e.g., three) LEDs. A first beam pattern (e.g., beam pattern  604 ) may, for example, represent the specified target illuminance as provided by a first LED/carrier/lens combination. Second and third beam patterns (e.g., beam patterns  606  and  608 ) may, for example, represent the specified target illuminance delivered by second and third LEDs of an LED-based lighting system. As can be seen, each beam pattern may be rotated with respect to each of the other beam patterns by virtue of the rotation of each LED (e.g., as described in relation to  FIG. 4 ) of the LED-based lighting system. 
         [0066]    As per an example, beam patterns  604 - 608 , as may be generated by a three-LED lighting system, may be rotated by 30 degrees with respect to each other as may be calculated from equation (1). In other words, for example, a substantially square beam pattern may be generated by each LED of an LED-based lighting system and the phase rotation of each beam pattern may be substantially equivalent to the phase rotation of each LED as mounted to its respective PCB. Accordingly, due to the rotation of beam patterns  604 - 608 , any disturbances and/or imperfections that may exist within each of the beam patterns  604 - 608  individually may tend to be blended together (e.g., averaged). 
         [0067]    Light projection diagram  620  may, for example, represent an alternate target illuminance that may be generated by first collecting the light into a specified target illuminance (e.g., spot beam patterns  604 - 608 ) and then partially diffusing the specified target illuminance into a broader beam pattern (e.g., beam pattern  622 ). Partial diffusion may result, for example, when the target illuminance from portions of one or more LED/carrier/lens combinations is diffused while the target illuminance from portions of the remaining LED/carrier/lens combinations is not diffused. Since spot beam patterns  604 - 608  are partially diffused, a concentration of light (e.g., concentration  624 ) may exist at a center portion of beam pattern  622 , while the remaining light may be diffused across a broader beam pattern (e.g., beam pattern  622 ). 
         [0068]    Light projection diagram  640  may, for example, represent an alternate target illuminance that may be generated by first collecting the light into a specified target illuminance (e.g., spot beam patterns  604 - 608 ) and then fully diffusing the specified target illuminance into a broader beam pattern (e.g., beam pattern  642 ). Full diffusion may result, for example, when the target illuminance from all LED/carrier/lens combinations is diffused (e.g., as illustrated in  FIG. 3 ). Since spot beam patterns  604 - 608  are being fully diffused, a beam pattern substantially free from a concentration of light within the middle of the beam pattern (e.g., beam pattern  642 ) may result. Beam pattern  620  and  640  may, for example, be compliant with beam pattern standards as may be promulgated by the Department of Transportation or the Economic Commission for Europe. 
         [0069]    Turning to  FIG. 7 , illustrations  700 ,  720  and  740  exemplify variations in LED placement within the aperture of a carrier from a plan view perspective. Looking down into the bowl of carrier  702  of illustration  700 , for example, it can be seen that LED  706  may be centered within aperture  704  as illustrated. The resulting target illuminance (e.g., as may be projected by LED  706 , carrier  702 , and an associated lens/diffuser combination) may be depicted by light projection  708 , which may be substantially centered along an optical axis (e.g., optical axis  710  of LED  706 ) as shown. 
         [0070]    Alternately, LED  726  may be offset within aperture  724  per illustration  720 , where it can be seen that LED  726  may be offset to the upper right-hand corner within aperture  724  as illustrated. The resulting target illuminance (e.g., as may be projected by LED  726 , carrier  722 , and an associated lens/diffuser combination) may be depicted by light projection  728 , which may be offset below and to the left of optical axis  730  as shown. In general, as LED  726  moves upward and toward the right relative to aperture  724 , light projection  728  may be inverted and may, therefore, move downward and toward the left relative to optical axis  728 . 
         [0071]    Alternately, LED  746  may be offset within aperture  744  per illustration  740 , where it can be seen that LED  746  may be offset to the upper left-hand corner within aperture  744  as illustrated. The resulting target illuminance (e.g., as may be projected by LED  746 , carrier  742 , and an associated lens/diffuser combination) may be depicted by light projection  748 , which may be offset below and to the right of optical axis  750  as shown. In general, as LED  746  moves upward and toward the left relative to aperture  744 , light projection  748  may be inverted and may, therefore, move downward and toward the right relative to optical axis  748 . 
         [0072]    Turning to  FIG. 8 , an exemplary LED-based lighting fixture  800  is illustrated, which may include a bezel  802  and a body portion  808  with heat sink fins  852  extending from body portion  808 . Bezel  802  may, for example, enclose one or more lenses  806 , a plate (e.g., transparent plate  804 ), and a PCBA (not shown) positioned against body portion  808 . Lenses  806  may be retained against transparent plate  804  by one or more carriers (not shown) extending from the PCBA. The PCBA may include one or more LEDs (not shown) and control circuitry (not shown) to enable regulation of power provided to the one or more LEDs. Transparent plate  804  may be sealed to bezel  802  (e.g., via a first gasket), and bezel  802  may be sealed to body portion  808  (e.g., via a second gasket), such that an interior of bezel  802  may house the PCBA, the carrier, lenses  806 , and transparent plate  804 , and such that the interior of bezel  802  may be sealed from moisture and/or other particulates. 
         [0073]    In addition to the bi-convex, plano-convex, equi-convex, and Fresnel lens configurations previously described, it should be noted that lenses  806  may include a bi-focal and/or a multi-focal configuration (e.g., 3 or more foci). Furthermore, the bi- and/or multi-focal configuration may coexist with one or more of the bi-convex, plano-convex, equi-convex, and Fresnel lens configurations. For example, a bi-convex lens configuration may also include a bi-focal configuration. In another example, a Fresnel lens configuration may also include a multi-focal configuration. A person of ordinary skill in the art will appreciate that many more combined configurations are possible beyond those specifically discussed herein. 
         [0074]    Turning to  FIG. 9 , a light collection and projection system  900  is exemplified, which may include a PCBA  902  including one or more LEDs (not shown) and associated bias and control circuitry  910  mounted thereon. Light collection and projection system  900  may further include a lens structure  914  and a carrier  912  that may include one or more bowl portions (not shown) positioned to receive lens structure  914 . 
         [0075]    Lens structure  914  may be positioned in an optimized geometric relationship with respect to PCBA  902 . For example, carrier  912  may include one or more extension portions (e.g., legs  926 ) which may interconnect with PCBA  902  to achieve only a single geometric relationship (e.g., the optimized geometric relationship). Further, the one or more extension portions (e.g., legs  926 ) may be dimensioned with a predetermined span to achieve an optimized separation distance between lens structure  914  and the LEDs of PCBA  902  and/or to achieve an optimized separation distance between a bottom portion of carrier  912  (e.g., rearward surface  1622  of  FIG. 16 ) and the LEDs of PCBA  902  (e.g., forward portion  1605  of  FIG. 16 ). Such an optimized separation distance may, for example, facilitate a predetermined portion of the photometric distribution of the LEDs to be collected and passed through lens structure  914  and/or may prohibit a predetermined portion of the photometric distribution of the LEDs from being collected and passing through lens structure  914 . 
         [0076]    The one or more bowls of carrier  912  may be shaped to enable and/or prohibit the predetermined portion of the photometric distribution of the LEDs to be collected and passed through lens structure  914 . Furthermore, carrier  912  may exhibit a non-reflective color (e.g., black) and/or a non-reflective texture (e.g., a coarse texture) so as to be substantially non-reflective of any light that may be incident on carrier  912 . 
         [0077]    Lens structure  914  may include one or more lenses  932  for subtending light emitted by the LEDs of the PCBA  902 . As exemplified in  FIG. 9 , lens structure  914  may include two lenses  932 . Alternately, a lens structure may include more than two lenses  932  (e.g., 3, 4, 5, 6, or more lenses). Lens structure  914  may include one or more extensions  920 , which may engage portions of an LED-based lighting fixture (e.g., transparent plate  804  of  FIG. 8 ). 
         [0078]    The predetermined portion of the photometric distribution of the LEDs may be collected and passed through discrete regions of the one or more lenses  932  (e.g., where the number of regions may correspond to a number of foci of each lens  932 ). For example, a bi-focal lens (e.g., lens  932 ) may have two discrete regions (e.g., first and second regions  933 ,  935 ), each region having a focus. In another example, a multi-focal lens may have three or more discrete regions, each region having a focus. In the above examples, the focus of each region may be the same as or different from the focus of one or more of the other regions. 
         [0079]    Turning to  FIG. 10 , a light collection and projection system  1000  is exemplified, which may include a lens structure  1014  and a carrier  1012  that may include one or more bowl portion  1030  positioned to receive lens structure  1014 . Each bowl portion  1030  may have an aperture  1024  extending through the bowl portion  1030  and one or more extension portions (e.g., legs  1026 ) extending from the bowl portion  1030  to facilitate in collection and/or exclusion of a predetermined portion of the photometric distribution from one or more LEDs (e.g., LEDs  402 ,  404  of  FIG. 4 ) on a PCBA (e.g., PCBA  400  of  FIG. 4 ). For example, aperture  1024  and legs  1026  may be positioned oppositely of the lens structure  1014 . In another example, legs  1026  may be dimensioned to create an optimized separation distance between a portion of the LEDs (e.g., bottom portion  1608  of  FIG. 16 ) and one or more of lens structure  1014  and/or carrier  1012 . In another example, each bowl portion  1030  may have two or more legs  1026 . 
         [0080]    The one or more extension portions (e.g., legs  1026 ) may each have a mechanical indexing feature (e.g., feet  1028 ,  1029 ) for interfacing with a corresponding mechanical indexing feature (e.g., holes  406  of  FIG. 4 ) of the PCBA. Each of the mechanical indexing features may be similarly dimensioned, except that at least one mechanical indexing feature (e.g., foot  1029 ) may be dimensioned differently from every other mechanical indexing feature, and this difference in dimension may correspond to a differently dimensioned mechanical indexing feature of the PCBA. For example, foot  1029  may ensure that carrier  1012  is interconnected with the PCBA in an optimal geometric relationship (e.g., right side up). In another example, foot  1029  may have a larger dimension than feet  1028 . A person skilled in the art will appreciate that additional configurations and dimensions may be possible to facilitate an optimal geometric relationship. 
         [0081]    Turning to  FIG. 11 , a cross-section of a light collection and projection system  1100  is exemplified, which may include a lens structure  1114  in alignment with and/or affixed to a carrier  1112 . For example, lens structure  1114  may be removably fixed to carrier  1112  (e.g., via corresponding friction-based locking mechanisms). In another example, lens structure  1114  may be permanently fixed to carrier  1112  (e.g., via adhesive). In another example, lens structure  1114  may be affixed to carrier  1112  by both corresponding friction-based locking mechanisms and adhesive. 
         [0082]    Carrier  1112  may include one or more locking mechanisms (e.g., friction-based male locking mechanisms  1118 ) which may be configured to interconnect with corresponding locking mechanisms (e.g., friction-based female locking mechanisms  1116 ) of lens structure  1114 . Further, one or more of the friction-based male locking mechanisms may include a bulb  1119 , and one or more of the friction-based female locking mechanisms may include a rib  1117 , such that upon interconnection and/or disconnection bulb  1119  passes across rib  1117 . Accordingly, friction-based male locking mechanisms  1118  may be capable of enough deflection to allow bulb  1119  to pass over rib  1117 . 
         [0083]    For example, upon interconnection, friction-based male locking mechanisms  1118  may begin in an undeflected position, may deflect to a maximum deflection position when bulb  1119  passes across rib  1117 , and may return to their undeflected positions. In another example, upon interconnection, friction-based male locking mechanisms  1118  may begin in an undeflected position, may deflect to a maximum deflection position when bulb  1119  passes across rib  1117 , and may deflect to an intermediate position between the undeflected position and the maximum deflection position. 
         [0084]    In either of the above examples, lens structure  1114  may be attached (e.g., removably attached) to carrier  1112  by the engagement of one or more friction-based male locking mechanisms  1118  with one or more friction-based female locking mechanisms  1116 . The attachment may be facilitated by an interference (e.g., frictional) fit between the male and female locking mechanisms and/or by a torsional clamping which occurs between at least two opposing male locking mechanisms (e.g., as exemplified in  FIG. 11 ). While the bulb  1119  and rib  1117  of the male and female locking mechanisms, respectively, have been illustrated with smoothly shaped contours (e.g., capable of removable attachment), a person of ordinary skill in the art will appreciate that other shaped contours may be employed to achieve different modes of attachment (e.g., permanent attachment). 
         [0085]    Turning to  FIGS. 12A and 12B ,  FIG. 12A  illustrates a back side  1215  of a lens structure  1214  which may be capable of interconnection with a front side  1213  of a carrier  1212  as illustrated in  FIG. 12B . Upon interconnection, lens structure  1214  and carrier  1212  may form a light collection and projection system (e.g., light collection and projection system  1100  of  FIG. 11 ). 
         [0086]    Lens structure  1214  may have one or more mechanical indexing features (e.g., holes  1261  and/or pegs  1265 ) for interfacing with a corresponding mechanical indexing feature (e.g., pegs  1262  and/or slot  1266 ) of carrier  1212 . The mechanical indexing features of lens structure  1214  may be particularly suited to facilitate interconnection with the mechanical indexing features of carrier  1212  in an optimized geometric relationship. 
         [0087]    For example, pegs  1262  may be capable of interconnection with holes  1261  in order to align lens structure  1214  with carrier  1212  (e.g., such that each lens  1232  is centered over a corresponding aperture  1224 ). In another example, a single peg  1265  may be capable of interconnection with a single slot  1266  in order to ensure that lens structure  1214  may interconnect with carrier  1212  in only a single configuration (e.g., the optimized geometric relationship). A person of ordinary skill in the art will appreciate that other configurations may be possible to achieve the optimized geometric relationship. 
         [0088]    Turning to  FIG. 13 , a right side  1315  of a lens structure  1314  is exemplified, which may include one or more lenses  1332  for subtending light (e.g., by diffraction) emitted by one or more LEDs (e.g., LED  1404  of  FIG. 14 ). Each lens  1332  may include one or more discrete regions (e.g., first and second regions  1333 ,  1335 ), and each discrete region may have similar or different foci to enable light to be subtended similarly or differently from each other region. For example, lens  1332  may have a first region  1333  with a first focus, and a second region  1335  with a second focus different from the first focus. In another example, a lens may have a first region with a first focus, a second region with a second focus, and a third region with a third focus. In this example, each of the first, second, and third foci may be similar or different. 
         [0089]    Each discrete region may be formed by opposing surfaces of the lens  1332 . For example, first region  1333  may be formed by a first inner surface  1371  and a first outer surface  1372 . In another example, second region  1335  may be formed by a second inner surface  1375  and a second outer surface  1376 . The first inner surface  1371  and second inner surface  1375  may be substantially in alignment, or may be substantially out of alignment (e.g., as exemplified in  FIG. 13 ). The first outer surface  1372  and second outer surface  1376  may be substantially in alignment, or may be substantially out of alignment (e.g., as exemplified in  FIG. 13 ). Thus, where corresponding surfaces may be out of alignment, a surface overhang (e.g., overhang  1377 ) and/or surface underhang (e.g., underhang  1378 ) may serve to join the unaligned surfaces. 
         [0090]    Furthermore, while the disalignment of each of surfaces  1371 ,  1372 ,  1375 , and  1376  are exemplified along a plane  1379  extending through lens  1332  (e.g., from right side  1315  to a side opposing right side  1315 ), this need not be the case. Plane  1379  of  FIG. 13  merely illustrates one example where first region  1333  is divided from second region  1335  roughly along a single plane (e.g., plane  1379 ). A person of ordinary skill in the art will appreciate that the first and second regions may be divided along other planes (e.g., through a center of lens  1332 ), or may be divided along multiple planes corresponding to the inner and outer surfaces (not shown). 
         [0091]    Turning to  FIG. 14 , a right side cross-sectional view of a light collection and projection system  1400  is exemplified, which may include a lens structure  1414  spaced with a first optimal separation distance from an LED  1404  on a PCBA  1402  to optimize subtending of light through lens structure  1414 . The LED  1404  may be positioned to emit light in an effective span of emission  1405  and along an axis of symmetry  1407  of the effective span  1405 . 
         [0092]    The first optimal separation distance may be provided for by a carrier  1412 , which may include one or more apertures (e.g., aperture  1424 ) corresponding to one or more lenses (e.g., lens  1432 ) of lens structure  1414 . Axis of symmetry  1407  may be normal or inclined with respect to PCBA  1402  to optimize travel of effective span  1405  toward lens  1432 . Furthermore, lens  1432  may have a central axis  1433  which may be collinear, parallel (as exemplified in  FIG. 14 ), or inclined with respect to axis of symmetry  1407  to optimize light subtended (e.g., refracted) by lens  1432 . 
         [0093]    Aperture  1424  may permit at least a portion of the light emitted by LED  1404  to be subtended by lens  1432 . For example, a first portion (e.g., span  1481 ) may travel from LED  1404  to a first distinct region (e.g., first region  1333  of  FIG. 13 ) of lens  1432 . Span  1481  may pass through lens  1432  and may be subtended (e.g., refracted) by lens  1432  to produce subtended span  1491 . Subtended span  1491  may include light rays that travel in a direction substantially parallel to central axis  1433  of lens  1432  (e.g., collimated light). 
         [0094]    In another example, a second portion (e.g., span  1482 ) may travel from LED  1404  to a second distinct region (e.g., second region  1335  of  FIG. 13 ) of lens  1432 . Span  1482  may pass through lens  1432  and may be subtended (e.g., refracted) by lens  1432  to produce subtended span  1492 . Subtended span  1492  may include light rays that travel in a direction substantially inclined (e.g., downward) with respect to central axis  1433  of lens  1432  (e.g., focused light). 
         [0095]    In another example, a third portion (e.g., span  1483 ) may travel from LED  1404  to a surface underhand and/or overhang region (e.g., overhang  1377  of  FIG. 13 ) of lens  1432 . Span  1483  may pass through lens  1432  and may be subtended (e.g., refracted) by lens  1432  to produce spill light (e.g., uncontrolled light). Due to the uncontrolled nature of span  1483 , the surface underhang and/or overhang region may be minimized or eliminated so that span  1483  is relatively small compared to spans  1481 ,  1482 . However, it may be impossible to completely eliminate the surface underhand and/or overhang region due to limitations of manufacturing processes. 
         [0096]    While aperture  1424  may permit at least a portion of the light emitted by LED  1404  to be subtended by lens  1432 , carrier  1412  may prevent at least a portion of the light emitted by LED  1404  from being subtended by lens  1432 . Further, carrier  1412  may be spaced a second optimal separation distance from LED  1404  to optimize the degree to which light is prevented from passing to lens  1432 . For example, a fourth portion (e.g., span  1484 ) and a fifth portion (e.g., span  1485 ) may each travel from LED  1404  toward carrier  1412  (e.g., bowl portion  1430 ). Carrier  1412  may subtend (e.g., reflect) the light away from lens  1432  and/or may absorb the light, such that light incident on carrier  1412  does not travel toward lens  1432 . 
         [0097]    Furthermore, a portion of light emitted by LED  1404  may travel away from both lens  1432  and carrier  1412 . For example, a sixth portion (e.g., span  1486 ) and a seventh portion (e.g., span  1487 ) may travel away from LED  1404  without being incident on either lens structure  1414  or carrier  1412 . Spans  1486 ,  1487  may be captured by other elements of an LED-based lighting system (e.g., LED-based lighting system  800  of  FIG. 8 ) when light collection and projection system  1400  is positioned within such an LED-based lighting system. Thus, the only light which may exit from the LED-based lighting system during operation of the light collection and projection system  1400  may be subtended spans  1491  and  1492 . 
         [0098]    Furthermore, while axis of symmetry  1407  and central axis  1433  have been exemplified in  FIG. 14  as being substantially horizontally disposed, light collection and projection system  1400  may be mounted within an LED-based lighting system in a substantially non-horizontal configuration. For example, one or both of axis of symmetry  1407  and central axis  1433  may be inclined with respect to a horizontal plane. In another example, axis of symmetry  1407  may have an incline with respect to a horizontal plane of between about 0.0 degrees and about 20 degrees (e.g., about 7.5 degrees). In another example, subtended span  1491  may have an incline with respect to a horizontal plane of between about 0.0 degrees and about 20 degrees (e.g., about 7.5 degrees). In another example, subtended span  1492  may have an incline with respect to a horizontal plane that is greater than an incline of subtended span  1491  with respect to the horizontal plane. 
         [0099]    As with previous embodiments of the present invention, it is understood that changing the geometric relationship of lens structure  1414  and/or carrier  1412  with respect to LED  1404  may cause a modification of the target illuminance of light subtended by lens  1432 . Thus, lens structure  1414  and/or carrier  1412  may be optimally positioned to achieve a desired target illuminance. Furthermore, each discrete region of lens  1432  may subtend the light passing through lens  1432  so that it travels from lens  1432  in a particular direction or directions (e.g., diffused, collimated, focused, and/or shifted light). 
         [0100]    Turning to  FIG. 15 , a top side cross-sectional view of a light collection and projection system  1500  is exemplified, which may include a lens structure  1514  spaced with a first optimal separation distance from one or more LEDs  1504  on a PCBA  1502 . The LEDs  1504  may each be positioned to emit light in an effective span of emission  1505  and along an axis of symmetry  1507  of respective effective spans  1505 . 
         [0101]    The first optimal separation distance may be provided for by a carrier  1512 , which may include one or more apertures (e.g., apertures  1524 ) corresponding to one or more lenses (e.g., lenses  1532 ) of lens structure  1514 . Axes of symmetry  1507  may be normal or inclined with respect to PCBA  1502  to optimize travel of effective spans  1505  toward lenses  1532 . Furthermore, lenses  1532  may each have a central axis  1533  which may be collinear (as exemplified in  FIG. 15 ), parallel, or inclined with respect to each axis of symmetry  1507 , respectively, to optimize light subtended (e.g., refracted) by lenses  1532 . 
         [0102]    Each aperture  1524  may permit at least a portion of the light emitted by a single LED  1504  to be subtended by a single lens  1532 , respectively. For example, a first portion of light (e.g., span  1581 ) may travel from a first LED  1504  to a first distinct region (e.g., first region  1333  of  FIG. 13 ) of lens  1532 . Span  1581  may pass through lens  1532  and may be subtended (e.g., refracted) by lens  1532  to produce subtended span  1591 . Subtended span  1591  may include light rays that travel in a direction substantially parallel to central axis  1533  of lens  1532  (e.g., collimated light). 
         [0103]    In another example, a second portion of light (e.g., span  1582 ) may travel from the first LED  1504  to a second distinct region (e.g., second region  1335  of  FIG. 13 ) of lens  1532 . Span  1582  may pass through lens  1532  and may be subtended (e.g., refracted) by lens  1532  to produce subtended span  1592 . Subtended span  1592  may include light rays that travel in a direction substantially inclined (e.g., downward) with respect to central axis  1533  of lens  1532  (e.g., focused light). As exemplified in  FIG. 15 , subtended span  1592  may be non-collimated light. 
         [0104]    While apertures  1524  may permit at least a portion of the light emitted by each LED  1504  to be subtended by a respective lens  1532 , carrier  1512  may prevent at least a portion of the light emitted by LEDs  1504  from being subtended by any of lenses  1532 . Further, carrier  1512  may be spaced a second optimal separation distance from LED  1504  to optimize the degree to which light is prevented from passing to lens  1532 . For example, a third portion of light (e.g., span  1583 ) and a fourth portion of light (e.g., span  1584 ) may each travel from the first LED  1504  toward carrier  1512  (e.g., bowl portion  1530 ). Carrier  1512  may subtend (e.g., reflect) the light away from lens  1532  and/or may absorb the light, such that light incident on carrier  1512  does not travel toward lens  1532 . 
         [0105]    In addition, carrier  1512  may have one or more obstructions (e.g., walls  1531 ) extending between bowl portions  1530  and PCBA  1502  to further prevent passage of light from the first LED  1504  to a non-corresponding lens  1532  (e.g., a lens  1532  not immediately in front of the first LED  1504 ). Furthermore, a portion of light emitted by first LED  1504  may travel away from both lens  1532  and carrier  1512 . For example, a fifth portion (e.g., span  1585 ) may travel away from first LED  1504  without being incident on either lens structure  1514  or carrier  1512 . Span  1585  may be captured by other elements of an LED-based lighting system (e.g., bezel  802  of LED-based lighting system  800  of  FIG. 8 ) when light collection and projection system  1500  is positioned within such an LED-based lighting system. Thus, the only light which may exit from the LED-based lighting system during operation of the light collection and projection system  1500  may be subtended spans  1591  and  1592 . 
         [0106]    Furthermore, while the above discussion has been made with reference to the first LED  1504 , it is understood that similar spans and subtended spans may be produced with regard to additional LEDs (e.g., second, third, fourth, fifth, sixth, or more LEDs). In addition, although one or more obstructions (e.g., walls  1531 ) have been illustrated in  FIG. 15  as between two axes of symmetry  1507  of two opposing LEDs  1504 , it is understood that one or more obstructions may be disposed between any and/or every LED in a system with more than two LEDs. 
         [0107]    Based on the foregoing embodiments and descriptions, it may be understood that a light collection and projection system may include a lens structure (e.g., lens structure  914  of  FIG. 9 ) interconnected with a carrier (e.g., carrier  912  of  FIG. 9 ), the lens structure spaced from one or more LEDs (e.g., LEDs  1504  of  FIG. 15 ) on a PCBA (e.g., PCBA  902  of  FIG. 9 ) by the carrier. Furthermore, the lens structure may have one or more lenses (e.g., lens  1332  of  FIG. 13 ), each lens having one or more discrete regions (e.g., first and second regions  1333 ,  1335  of  FIG. 13 ), and each discrete region having a focus, respectively. 
         [0108]    The focus of each region may be defined by the depth and curvature of each region, respectively. For example, the focus of a region may be defined by the relative distance between inner and outer surfaces of that region along its span in any direction (e.g., the distance between first inner surface  1371  and first outer surface  1372 ). Furthermore, the focus of each region may be selected to produce a particular subtending of light (e.g., no effect, diffusion of light, focusing of light, collimating of light, shifting of light, or any combination thereof). For example, a first region may be appropriately shaped to collimate light along a vertical span (e.g., as exemplified with lens  1432  in  FIG. 14 ) and to collimate light along a horizontal span (e.g., as exemplified with lens  1532  in  FIG. 15 ). In another example, a second region may be appropriately shaped to focus and shift light (e.g., bend it downward) along a vertical span (e.g., as exemplified with lens  1432  in  FIG. 14 ) and to focus light along a horizontal span (e.g., as exemplified with lens  1532  in  FIG. 15 ). 
         [0109]    A person of ordinary skill in the art will appreciate the limitations of conveying this invention in various drawings as herein disclosed. However, it is understood that a region of a lens may have any one or more of the above described characteristics of subtending light. In another example, a discrete region may collimate light in a first span (e.g., along a height) and diffuse light in a second span (e.g., along a width) normal to the first span. In another example, a discrete region may have no effect on the light in a first span and shift the light in a second span normal to the first span. 
         [0110]    In general, a lens having only one discrete region may be capable of producing a single light projection at a distance forward of a LED-based lighting system. Alternately, a lens having two or more discrete regions may be capable of producing two or more light projections at the distance forward of the LED-based lighting system. The two or more light projections may be separate, bordering each other, or overlapping. Furthermore, each light projection may have similar or different characteristics of subtending light to every other light projection. Thus, the lens having two or more discrete regions may be more versatile and, therefore, better able to provide light forwardly of the LED-based lighting system in accordance with specialized needs. 
         [0111]    Turning to  FIG. 16 , a cross-sectional segment of a light collection and projection system  1600  is exemplified, which may include a lens structure  1614  spaced from one or more LEDs  1604  on a PCBA  1602  by a carrier  1612 . Lens structure  1614  may be spaced with a first optimal separation distance from the LEDs  1604 , and carrier  1612  may be spaced with a second optimal separation distance from the LEDs  1604 . The first and second optimal separation distances may be defined by one or more surfaces of lens structure  1614 , one or more surfaces of carrier  1612 , and/or one or more surfaces and/or regions of LEDs  1604 . 
         [0112]    Lens structure  1614  may include a rearward surface  1671 , which may be positioned to be facing PCBA  1602 . For example, rearward surface  1671  of lens structure  1614  may include a curvature (e.g., having a convex shape) with a rearward tip  1672  and a forward perimeter  1673 . Forward perimeter  1673  may be spaced from PCBA  1602  by a distance  1691 , and rearward tip  1672  may be spaced from PCBA  1602  by a distance  1692 . One or both of distances  1691  and  1692  may contribute to the first optimal separation distance of lens structure  1614  from LEDs  1604 . 
         [0113]    Carrier  1612  may include a rearward surface  1622  positioned to be facing PCBA  1602 , and a forward surface  1623  facing oppositely of rearward surface  1622 . Forward surface  1623  may be spaced from PCBA  1602  by a distance  1691  (e.g., abutting forward perimeter  1673  of lens structure  1614 ), and rearward surface  1622  may be spaced from PCBA  1602  by a distance  1693 . One or both of distances  1691  and  1693  may contribute to the second optimal separation distance of carrier  1612  from LEDs  1604 . 
         [0114]    PCBA  1602  may include a forward surface  1603  upon which the one or more LEDs  1604  may be secured. LEDs  1604  may include a rearward portion  1608  secured to forward surface  1603  of PCBA  1602 , and a forward portion  1605  secured to rearward portion  1608 . For example, rearward portion  1608  may include a rearward surface  1609  which abuts forward surface  1603  of PCBA  1602  (e.g., the distance between rearward surface  1609  of rearward portion  1608  and forward surface  1603  of PCBA  1602  may be zero). 
         [0115]    In another example, LEDs  1604  may have a deck  1607  upon which a light source may be located. Deck  1607  may face oppositely of rearward surface  1609  from rearward portion  1608 . Deck  1607  may be spaced from PCBA  1602  by a distance  1694 , which may contribute to one or both of the first and second optimal separation distances. 
         [0116]    In another example, forward portion  1605  of LEDs  1604  may extend from rearward portion  1608  (e.g., from deck  1607 ). Forward portion  1605  may enclose a light source (e.g., the light source positioned on deck  1607 ), and may be dome shaped. Forward portion  1605  may include a forward tip  1606  spaced a distance  1696  from PCBA  1602 . Forward tip  1606  may represent a distance of the one or more LEDs  1604  that is furthest from PCBA  1602 . Distance  1696  may contribute to one or both of the first and second optimal separation distances. 
         [0117]    In another example, forward portion  1605  of LED  1604  may include an intermediate position  1610  located between deck  1607  and forward tip  1606 . For example, intermediate position  1610  may be ½, ⅓, ⅔, ¼, ¾, ⅕, ⅖, ⅗, or ⅘, of the way from deck  1607  to forward tip  1606 . Intermediate position  1610  may be spaced from PCBA  1602  by a distance  1695 , which may contribute to one or both of the first and second optimal separation distances. 
         [0118]    As discussed above, each of distances  1691 - 1696  may contribute to one or both of the first and second optimal separation distances. The first optimal separation distance (OSD 1 ), or the distance between lens structure  1614  and LEDs  1604 , may be represented by any one or more of equations (2)-(7) as: 
         [0000]      OSD1=1691,  (2)
 
         [0000]      OSD1=1691-1694,  (3)
 
         [0000]      OSD1=1691-1695,  (4)
 
         [0000]      OSD1=1691-1696,  (5)
 
         [0000]      OSD1=1692,  (6)
 
         [0000]      OSD1=1692-1694,  (7)
 
         [0000]      OSD1=1692-1695,  (8)
 
         [0000]      OSD1=1692-1696,  (9)
 
         [0119]    Where OSD 1  is the first optimal separation distance, and  1691 - 1696  are the distances as herein described. For example, OSD 1  as exemplified by equation (2), above, may be between about 0.4 inches and about 0.6 inches (e.g., about 0.506 inches). In another example, OSD 1  as exemplified by equation (3), above, may be between about 0.477 inches and about 0.485 inches (e.g., about 0.481 inches). In another example, OSD 1  as exemplified by equation (4), above, may be between about 0.428 inches and about 0.473 inches (e.g., about 0.450 inches). In another example, OSD 1  as exemplified by equation (5), above, may be between about 0.416 inches and about 0.422 inches (e.g., about 0.419 inches). In another example, OSD 1  as exemplified by equation (6), above, may be between about 0.3 inches and about 0.5 inches (e.g., about 0.401 inches). In another example, OSD 1  as exemplified by equation (7), above, may be between about 0.372 inches and about 0.380 inches (e.g., about 0.376 inches). In another example, OSD 1  as exemplified by equation (8), above, may be between about 0.323 inches and about 0.368 inches (e.g., about 0.345 inches). In another example, OSD 1  as exemplified by equation (9), above, may be between about 0.311 inches and about 0.317 inches (e.g., about 0.314 inches). 
         [0120]    The second optimal separation distance (OSD 2 ), or the distance between carrier  1612  and LEDs  1604 , may be represented by any one or more of equations (8)-(13) as: 
         [0000]      OSD2=1691,  (10)
 
         [0000]      OSD2=1691-1694,  (11)
 
         [0000]      OSD2=1691-1695,  (12)
 
         [0000]      OSD2=1691-1696,  (13)
 
         [0000]      OSD2=1693,  (14)
 
         [0000]      OSD2=1693-1694,  (15)
 
         [0000]      OSD2=1693-1695,  (16)
 
         [0000]      OSD2=1693-1696,  (17)
 
         [0121]    Where OSD 2  is the second optimal separation distance, and  1691 - 1696  are the distances as herein described. For example, OSD 2  as exemplified by equation (10), above, may be between about 0.4 inches and about 0.6 inches (e.g., about 0.506 inches). In another example, OSD 2  as exemplified by equation (11), above, may be between about 0.477 inches and about 0.485 inches (e.g., about 0.481 inches). In another example, OSD 2  as exemplified by equation (12), above, may be between about 0.428 inches and about 0.473 inches (e.g., about 0.450 inches). In another example, OSD 2  as exemplified by equation (13), above, may be between about 0.416 inches and about 0.422 inches (e.g., about 0.419 inches). In another example, OSD 2  as exemplified by equation (14), above, may be between about 0.09 inches and about 0.11 inches (e.g., about 0.10 inches). In another example, OSD 2  as exemplified by equation (15), above, may be between about 0.071 inches and about 0.079 inches (e.g., about 0.075 inches). In another example, OSD 2  as exemplified by equation (16), above, may be between about 0.022 inches and about 0.067 inches (e.g., about 0.045 inches). In another example, OSD 2  as exemplified by equation (17), above, may be between about 0.01 inches and about 0.016 inches (e.g., about 0.013 inches). 
         [0122]    A person of ordinary skill in the art will appreciate that the above ranges are given as examples only, and may be optimal for a specified LED (e.g., an Oslon 80 LED). Thus, a system incorporating LEDs of different sizes may necessarily require different first and second optimal separation distances than those exemplified. Nevertheless, such differently sized LEDs may be optimally spaced from corresponding lens structures and/or carriers to achieve the objectives outlined by the present invention. 
         [0123]    While  FIG. 16  exemplifies a lens structure and carrier similar to the configuration illustrated with respect to  FIGS. 1-5 , it is understood that the same principles of determining an optimal separation distance may be applied to the lens structure and carrier configuration illustrated with respect to  FIGS. 8-15 . Furthermore, a person of ordinary skill in the art will appreciate that the light collection and projection systems of the foregoing embodiments may be scalable to other sizes than those specifically referenced in any of the preceding examples (e.g., to smaller and/or larger sizes). 
         [0124]    Other aspects and embodiments of the present invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. It is intended, therefore, that the specification and illustrated embodiments be considered as examples only, with a true scope and spirit of the invention being indicated by the following claims.