Patent Publication Number: US-9416939-B2

Title: LED-based lighting fixture with textured lens

Description:
TECHNICAL FIELD 
     The present invention is directed generally to LED-based lighting fixtures employing textured lenses. More particularly, various inventive methods and apparatus disclosed herein relate to LED-based lighting fixtures with a lens having a textured portion with a plurality of unique textures. 
     BACKGROUND 
     Digital lighting technologies, i.e. illumination based on semiconductor light sources, such as light-emitting diodes (LEDs), offer a viable alternative to traditional fluorescent, HID, and incandescent lamps. Functional advantages and benefits of LEDs include high energy conversion and optical efficiency, durability, lower operating costs, and many others. Recent advances in LED technology have provided efficient and robust full-spectrum lighting sources that enable a variety of lighting effects in many applications. Some of the fixtures embodying these sources feature a lighting module, including one or more LEDs capable of producing different colors, e.g. red, green, and blue, as well as a processor for independently controlling the output of the LEDs in order to generate a variety of colors and color-changing lighting effects. 
     Some lighting fixtures may include one or more LEDs that include more than one die. For example, some lighting fixtures may include a single LED that has multiple dies. Also, for example, some lighting fixtures may include multiple LEDs that each includes at least one die. When more than one LED die is utilized in a lighting fixture, then banding and/or color shadows may occur at the edge of the beam pattern emitted by such lighting fixtures. 
     For example, if a lighting fixture includes a blue, green, and red LED in combination with a reflector partially surrounding the LEDs, the LED(s) that are most closely adjacent the reflector edge will be cut-off by the reflector from the main beam of the light output. Accordingly, the main beam of the light output will have a “white” color from the combined red, green, and blue light, but color banding will be present peripherally of the main beam of the light output. The color banding may be caused, for example, by the blocking of light output from one or more LEDs by the reflector edge. 
     Also, for example, a lighting fixture may include multiple LED dies and light emitted by one or more of the LED dies may exit the lighting fixture uncontrolled, thereby potentially causing streaks of light to appear peripherally of the main beam emitted by the lighting fixture. These streaks of light may be present in, for example, LED-based cove lights or linear grazing fixtures mounted close to a wall or other surface. Uncontrolled light may be emitted from the sides of the fixture due to Fresnel reflections and/or mechanical restraints of the lighting fixture. Such color bands and color shadows are generally not desirable for lighting fixtures. 
     Thus, there is a need in the art to provide a lens that may be implemented in a lighting fixture to reduce the presence of color banding and/or color shadows present in the light output of the lighting fixture. 
     SUMMARY 
     The present disclosure is directed to inventive methods and apparatus for a textured lens and, more specifically, to a lens having a textured portion with a plurality of unique textures utilized in a LED-based lighting fixture to reduce the presence of color banding and/or color shadows present in the light output of the lighting fixture. For example, the lens may be placed across the light output opening of a LED-based lighting fixture and intersect light output generated by a multi-die LED light source. The lens may include a substantially texture-free portion and a textured portion. The textured portion may have a plurality of distinct textures and may transition from a relatively light texture to a heavier texture across a width thereof. 
     Generally, in one aspect, the invention relates to a lighting fixture that includes a housing, an LED light source, and a lens. The housing defines at least one light output opening. The LED light source includes a plurality of LED dies, is retained within the housing, and emits a light output. At least some of the light output travels through the light output opening. The lens is provided across the light output opening and has a substantially texture-free portion and a textured portion. The textured portion is provided along at least a portion of a periphery of the lens. As the textured portion moves farther from the texture-free portion and closer to the periphery, texturing thereof transitions from a first texturing having a first depth, to a second texturing having a second depth greater than the first depth, to a third texturing having a third depth greater than the second depth. 
     In some embodiments the textured portion is provided around the majority of the periphery of the lens. In some versions of those embodiments the textured portion is provided around the entirety of the periphery of the lens. In some versions of those embodiments the texture-free portion constitutes a majority of the lens. In some versions of those embodiments the texture-free portion constitutes at least eighty percent of the lens. 
     In some embodiments the lens is an outermost lens of the lighting fixture. 
     Generally, in another aspect, the invention relates to a lighting fixture that includes a housing, an LED light source, and a lens. The LED light source is retained within the housing and emits a light output having a light output intensity and a plurality of unique spectrums. The lens is coupled to the housing and intersects at least some of the light output. The lens has a substantially texture-free portion and a textured portion. The texture-free portion intersects a continuous at least half of the light output intensity including a median value of the light output intensity. The textured portion gradually transitions from a first texturing having a first depth to a second texturing having a second depth at least four times greater than the first depth. The first texturing is more proximal to the texture-free portion than the second texturing is to the texture-free portion. 
     In some embodiments, the texture-free portion intersects at least seventy percent of the light output intensity. 
     In some embodiments, the texture-free portion intersects at least ninety percent of the light output intensity. In some versions of those embodiments, the textured area is provided around the entirety of a periphery of the lens. 
     In some embodiments, the textured area is provided around a majority of a periphery of the lens. 
     In some embodiments, the lens is substantially planar. In some versions of those embodiments the lens is rectangular. 
     In some embodiments, the texture-free portion is completely texture-free. 
     Generally, in another aspect, the invention relates to a lighting fixture that includes a housing, a multi-spectrum LED light source retained within the housing and emitting a light output, and a lens coupled to the housing. The LED light source has a light output intensity and the lens has a textured portion across at least a portion thereof. The lens intersects at least some of the light output. The textured portion extends substantially to the edge of the lens and includes a light texture zone most distal the edge having a light average depth of less than 0.002 inches and a heavy texture zone most proximal the edge having a heavy average depth at least twice the light average depth. 
     In some embodiments, the textured portion is integrally formed in an exterior facing surface of the lens. 
     In some embodiments, the lens includes a texture-free portion interior of the textured portion. In some versions of those embodiments the texture-free portion intersects at least fifty percent of the light output intensity of the intersected light. In some versions of those embodiments the texture-free portion intersects at least eighty percent of the light output intensity. 
     As used herein for purposes of the present disclosure, the term “LED” should be understood to include any electroluminescent diode or other type of carrier injection/junction-based system that is capable of generating radiation in response to an electric signal. Thus, the term LED includes, but is not limited to, various semiconductor-based structures that emit light in response to current, light emitting polymers, organic light emitting diodes (OLEDs), electroluminescent strips, and the like. In particular, the term LED refers to light emitting diodes of all types (including semi-conductor and organic light emitting diodes) that may be configured to generate radiation in one or more of the infrared spectrum, ultraviolet spectrum, and various portions of the visible spectrum (generally including radiation wavelengths from approximately 400 nanometers to approximately 700 nanometers). Some examples of LEDs include, but are not limited to, various types of infrared LEDs, ultraviolet LEDs, red LEDs, blue LEDs, green LEDs, yellow LEDs, amber LEDs, orange LEDs, and white LEDs (discussed further below). It also should be appreciated that LEDs may be configured and/or controlled to generate radiation having various bandwidths (e.g., full widths at half maximum, or FWHM) for a given spectrum (e.g., narrow bandwidth, broad bandwidth), and a variety of dominant wavelengths within a given general color categorization. 
     For example, one implementation of an LED configured to generate essentially white light (e.g., a white LED) may include a number of dies which respectively emit different spectra of electroluminescence that, in combination, mix to form essentially white light. In another implementation, a white light LED may be associated with a phosphor material that converts electroluminescence having a first spectrum to a different second spectrum. In one example of this implementation, electroluminescence having a relatively short wavelength and narrow bandwidth spectrum “pumps” the phosphor material, which in turn radiates longer wavelength radiation having a somewhat broader spectrum. 
     It should also be understood that the term LED does not limit the physical and/or electrical package type of an LED. For example, as discussed above, an LED may refer to a single light emitting device having multiple dies that are configured to respectively emit different spectra of radiation (e.g., that may or may not be individually controllable). Also, an LED may be associated with a phosphor that is considered as an integral part of the LED (e.g., some types of white LEDs). In general, the term LED may refer to packaged LEDs, non-packaged LEDs, surface mount LEDs, chip-on-board LEDs, T-package mount LEDs, radial package LEDs, power package LEDs, LEDs including some type of encasement and/or optical element (e.g., a diffusing lens), etc. 
     The term “light source” should be understood to refer to any one or more of a variety of radiation sources, including, but not limited to, LED-based sources (including one or more LEDs as defined above), incandescent sources (e.g., filament lamps, halogen lamps), fluorescent sources, phosphorescent sources, high-intensity discharge sources (e.g., sodium vapor, mercury vapor, and metal halide lamps), lasers, other types of electroluminescent sources, pyro-luminescent sources (e.g., flames), candle-luminescent sources (e.g., gas mantles, carbon arc radiation sources), photo-luminescent sources (e.g., gaseous discharge sources), cathode luminescent sources using electronic satiation, galvano-luminescent sources, crystallo-luminescent sources, kine-luminescent sources, thermo-luminescent sources, triboluminescent sources, sonoluminescent sources, radioluminescent sources, and luminescent polymers. 
     A given light source may be configured to generate electromagnetic radiation within the visible spectrum, outside the visible spectrum, or a combination of both. Hence, the terms “light” and “radiation” are used interchangeably herein. Additionally, a light source may include as an integral component one or more filters (e.g., color filters), lenses, or other optical components. Also, it should be understood that light sources may be configured for a variety of applications, including, but not limited to, indication, display, and/or illumination. An “illumination source” is a light source that is particularly configured to generate radiation having a sufficient intensity to effectively illuminate an interior or exterior space. In this context, “sufficient intensity” refers to sufficient radiant power in the visible spectrum generated in the space or environment (the unit “lumens” often is employed to represent the total light output from a light source in all directions, in terms of radiant power or “luminous flux”) to provide ambient illumination (i.e., light that may be perceived indirectly and that may be, for example, reflected off of one or more of a variety of intervening surfaces before being perceived in whole or in part). 
     The term “spectrum” should be understood to refer to any one or more frequencies (or wavelengths) of radiation produced by one or more light sources. Accordingly, the term “spectrum” refers to frequencies (or wavelengths) not only in the visible range, but also frequencies (or wavelengths) in the infrared, ultraviolet, and other areas of the overall electromagnetic spectrum. Also, a given spectrum may have a relatively narrow bandwidth (e.g., a FWHM having essentially few frequency or wavelength components) or a relatively wide bandwidth (several frequency or wavelength components having various relative strengths). It should also be appreciated that a given spectrum may be the result of a mixing of two or more other spectra (e.g., mixing radiation respectively emitted from multiple light sources). 
     For purposes of this disclosure, the term “color” is used interchangeably with the term “spectrum.” However, the term “color” generally is used to refer primarily to a property of radiation that is perceivable by an observer (although this usage is not intended to limit the scope of this term). Accordingly, the terms “different colors” implicitly refer to multiple spectra having different wavelength components and/or bandwidths. It also should be appreciated that the term “color” may be used in connection with both white and non-white light. 
     The term “lighting fixture” is used herein to refer to an implementation or arrangement of one or more lighting units in a particular form factor, assembly, or package. The term “lighting unit” is used herein to refer to an apparatus including one or more light sources of same or different types. A given lighting unit may have any one of a variety of mounting arrangements for the light source(s), enclosure/housing arrangements and shapes, and/or electrical and mechanical connection configurations. Additionally, a given lighting unit optionally may be associated with (e.g., include, be coupled to and/or packaged together with) various other components (e.g., control circuitry) relating to the operation of the light source(s). An “LED-based lighting unit” refers to a lighting unit that includes one or more LED-based light sources as discussed above, alone or in combination with other non LED-based light sources. A “multi-channel” lighting unit refers to an LED-based or non LED-based lighting unit that includes at least two light sources configured to respectively generate different spectrums of radiation, wherein each different source spectrum may be referred to as a “channel” of the multi-channel lighting unit. 
     The term “controller” is used herein generally to describe various apparatus relating to the operation of one or more light sources. A controller can be implemented in numerous ways (e.g., such as with dedicated hardware) to perform various functions discussed herein. A “processor” is one example of a controller which employs one or more microprocessors that may be programmed using software (e.g., microcode) to perform various functions discussed herein. A controller may be implemented with or without employing a processor, and also may be implemented as a combination of dedicated hardware to perform some functions and a processor (e.g., one or more programmed microprocessors and associated circuitry) to perform other functions. Examples of controller components that may be employed in various embodiments of the present disclosure include, but are not limited to, conventional microprocessors, application specific integrated circuits (ASICs), and field-programmable gate arrays (FPGAs). 
     It should be appreciated that all combinations of the foregoing concepts and additional concepts discussed in greater detail below (provided such concepts are not mutually inconsistent) are contemplated as being part of the inventive subject matter disclosed herein. In particular, all combinations of claimed subject matter appearing at the end of this disclosure are contemplated as being part of the inventive subject matter disclosed herein. It should also be appreciated that terminology explicitly employed herein that also may appear in any disclosure incorporated by reference should be accorded a meaning most consistent with the particular concepts disclosed herein. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the drawings, like reference characters generally refer to the same parts throughout the different views. Also, the drawings are not necessarily to scale, emphasis instead generally being placed upon illustrating the principles of the invention. 
         FIG. 1  illustrates a first embodiment of a lighting fixture having a textured lens across a light output opening thereof; the lighting fixture is shown adjacent an illumination surface. 
         FIG. 2  illustrates a section view of a portion of the textured lens of  FIG. 1 . 
         FIG. 3  illustrates a top view of the textured lens of  FIG. 1 . 
         FIG. 4  illustrates a second embodiment of a lighting fixture having a textured lens across a light output opening thereof; the lighting fixture is shown adjacent an illumination surface. 
         FIG. 5  illustrates a section view of a portion of the textured lens of  FIG. 4 . 
     
    
    
     DETAILED DESCRIPTION 
     Some lighting fixtures may include one or more LEDs that include more than one die. However, light output emitted by some of those lighting fixtures includes undesired banding and/or color shadows at the edge of the beam pattern due to, for example, cut-off from lighting fixture components and/or uncontrolled light from one or more LED dies. Thus, Applicants have recognized and appreciated that it would be beneficial to provide a lens that may be implemented in an LED-based lighting fixture to reduce the presence of color banding and/or color shadows present in the light output of the lighting fixture. More generally, Applicants have recognized and appreciated that it would be beneficial to employ a lens with a textured portion that may optionally include a plurality of unique textures across a width thereof. 
     In view of the foregoing, various embodiments and implementations of the present invention relate to a textured lens. 
     In the following detailed description, for purposes of explanation and not limitation, representative embodiments disclosing specific details are set forth in order to provide a thorough understanding of the claimed invention. However, it will be apparent to one having ordinary skill in the art having had the benefit of the present disclosure that other embodiments according to the present teachings that depart from the specific details disclosed herein remain within the scope of the appended claims. Moreover, descriptions of well-known apparatuses and methods may be omitted so as to not obscure the description of the representative embodiments. Such methods and apparatuses are clearly within the scope of the claimed invention. For example, various embodiments of the textured lens disclosed herein are depicted in combination with particular lighting fixtures having particular LED light sources. However, other LED-based lighting fixtures incorporating the textured lens are contemplated without deviating from the scope or spirit of the claimed invention. For example, a textured lens may be implemented in other LED-based lighting fixtures where a multi-source shadow or color banding is not desired proximal the edges of a beam pattern. Also, for example, a textured lens may be implemented in lighting fixtures where unwanted light coming from one direction of the lighting fixture needs to be blended with the main beam without causing a noticeable change in intensity or beam angle. 
     Referring initially to  FIG. 1 , in one embodiment a LED-based lighting fixture  10  is provided with a textured lens  30 . The lighting fixture  10  is illustrated schematically in  FIG. 1  and includes a housing  12 . The housing  12  retains the textured lens  30  across a light exit opening  14  thereof. The lens  30  is the outermost lens in the lighting fixture  10 . However, in other embodiments another lens (e.g., a non-textured lens) may be provided outward of the lens  30  across a light output opening and the lens  30  may be provided interiorly thereof across an interior light output opening. The housing  12  also retains a LED-based light source having a red LED  20 R, a green LED  20 G, and a blue LED  20 B. The LEDS  20 R,  20 G, and  20 B may optionally be mounted on a printed circuit board (PCB) and/or a heatsink supported within the housing  12 . The LEDS  20 R,  20 G, and  20 B may be powered simultaneously at given current levels to collectively produce substantially white light, powered simultaneously at other current levels to collectively produce other colors of light, and/or may be powered individually and/or in combination with one other of LEDs  20 R,  20 G, and  20 B to produce other colors of light. A controller may optionally be utilized in combination with the LEDS  20 R,  20 G, and/or  20 B to control the light output produced thereby. 
     Although three LEDs  20 R,  20 G, and  20 B are illustrated in  FIG. 1 , one of ordinary skill in the art having had the benefit of the present disclosure will recognize and appreciate that in alternative embodiments more or fewer LEDs may be provided, including LEDs of additional and/or alternative colors. For example, in some embodiments one or more white LEDs may be provided in addition to LEDS  20 R,  20 G, and  20 B. Additionally, one of ordinary skill in the art having had the benefit of the present disclosure will recognize and appreciate LEDs may be alternatively positioned and/or arranged within a lighting fixture in alternative embodiments. For example, in some embodiments the LEDs may be non-planar with respect to one another, non-planar with respect to a lens  30  of the lighting fixture  10 , non-centered within the housing  12 , and/or alternatively distributed within the housing  12 . 
     Provided about the LEDs  20 R,  20 G, and  20 B is a reflector  22 . Only two segments of reflector  22  are illustrated in  FIG. 1 , but it is understood that the reflector  22  may optionally extend completely about the LEDs  20 R,  20 G, and  20 B in some embodiments. One of ordinary skill in the art having had the benefit of the present disclosure will recognize and appreciate that in alternative embodiments alternative optical elements may optionally be provided in combination with the LEDs to direct a desired light distribution to the lens  30 . For example, in some embodiments a non-symmetric reflector may be provided about one or more LEDS, a reflector may provided only partially about the LEDs, and/or an optical lens may be provided over one or more LEDs. The reflector  22  is configured to generally direct light output from the LEDs  20 R,  20 G, and  20 B towards the textured lens  30 . 
     Three exemplary light rays are depicted emanating from each of the LEDS  20 R,  20 G, and  20 B. It is understood that each of the LEDs will emit many other light rays than those depicted herein, some of which may contact and be redirected by the reflector  22  one or more times. Light rays  20 R 1 ,  20 G 1 , and  20 B 1  are directed substantially perpendicular to the lens  30 , contact a substantially texture-free portion  32  thereof, and are transmitted therethrough without being substantially scattered. Other light rays will contact the substantially texture-free portion  32  at non-perpendicular angles (some after contacting reflector  22  one or more times) and will likewise be transmitted therethrough without being substantially scattered. The substantially texture-free portion  32  may alter the path of light rays transmitted therethrough depending on one or more factors such as, for example, the index of refraction of the substantially texture-free portion  32 , the incidence angle of the light ray(s), and/or the thickness of the substantially texture-free portion  32 . The light transmitted through substantially texture-free portion  32  is generally directed toward a main beam portion  3  of an illumination area  2 . 
     Light rays  20 R 2 ,  20 G 2 , and  20 B 2  are directed just beyond an upper extent of the reflector  22 , contact a textured portion  40  of the lens  30 , and are transmitted through, and scattered by, the textured portion  40 . Other light rays will contact the textured portion  40  (some after contacting reflector  22  one or more times) and will likewise be transmitted through and scattered by the lens  30 . Due to the gradually increasing texturing of lens  30  described herein, the light ray  20 R 2  that contacts the textured portion  40  most closely adjacent to the substantially texture-free portion  32  is scattered less than the light ray  20 G 2  (that contacts the textured portion  40  farther from substantially texture-free portion  32  than light ray  20 R 2 ). Likewise, light ray  20 G 2  is scattered less than the light ray  20 B 2  (that contacts the textured portion  40  farther from substantially texture-free portion  32  than light ray  20 G 2 ). The textured portion  40  may also optionally alter the path of light rays transmitted therethrough prior to the light rays contacting the textured surface depending on one or more factors such as, for example, the index of refraction of the textured portion  40 , the incidence angle of the beam, and/or the thickness of the textured portion  40 . 
     Other light rays  20 R 3 ,  20 G 3 , and  20 B 3  are also directed just beyond an upper extent of the reflector  22 , contact another section of the textured portion  40 , and are transmitted through, and scattered by, the textured portion  40 . Due to the gradually increasing texturing of lens  30  described herein, the light ray  20 B 3  is scattered less than the light ray  20 G 3 , and light rays  20 B 3  and  20 G 3  are both scattered less than the light ray  20 R 3 . The light transmitted through substantially textured portion  40  is generally directed toward a scattered beam portion  4  of the illumination area  2 . In lighting fixtures that do not implement the textured lens  30 , some or all of such portions of an illumination area peripheral of the main beam portion  5  may experience undesired color banding and/or shadows. 
     Referring to  FIG. 2 , a section view of a portion of the textured lens  30  of  FIG. 1  is illustrated. The section includes an edge  31  of the lens  30  and is taken along a portion of the textured portion  40  and a portion of the texture-free portion  32 . It is illustrated that the texture-free portion  32  has a substantially smooth texture-free exterior face  34  and that light rays transmitted therethrough such as light ray  39  are not substantially scattered. An imaginary dashed line  41 A generally represents the beginning of the textured portion  40  and the beginning of a lightly textured section  41  thereof. Dashed line  42 A generally represents the beginning of a medium textured section  42  of the textured portion  40  and dashed line  43 A generally represents the beginning of a heavy textured section  43  of the textured portion  40 . It is illustrated that the degree of texturing increases gradually across each section  41 ,  42 ,  43  as you move outward from the substantially texture-free section  32 . For example, the degree of texturing in medium textured section  42  is greater close to dashed line  43 A than it is close to dashed line  42 A. Light rays  491 ,  492 ,  493 , are illustrated transmitted through respective sections  41 ,  42 ,  43 . It is illustrated that the degree of scattering of the light rays  491 ,  492 ,  493  increases as the degree of texturing increases. 
     In some embodiments, the degree of texturing may increase linearly across all or portions of textured portion  40 . In other embodiments the degree of texturing may additionally or alternatively increase exponentially and/or vary according to some other function across all or portions of textured portion  40 . For example, in some alternative embodiments lightly textured section  41  may comprise a first substantially constant degree of texturing, medium textured section  42  may comprise a greater second substantially constant degree of texturing, and heavy texturing section  43  may comprise an even greater third substantially constant degree of texturing. Embodiments that implement a light texturing immediately adjacent the substantially texture-free area  32  and gradually increase texturing may eliminate the appearance of a visible transition line between textured and non-textured portions in the light output. Although substantially texture-free area  32  is illustrated as not having any texture at all, in alternative embodiments the substantially texture-free area  32  may contain a light texture across all or portions thereof that minimally affects light intensity of the light transmitted therethrough. For example, in some embodiments the substantially texture-free area  32  will have a texture on the outer surface thereof that is lighter than the texturing of the lightly textured section  41 . 
     In some embodiments, the lightly textured section  41  may have an average depth of approximately 0.0004 inches with a one degree minimum draft, the medium textured zone  42  may have an average depth of approximately 0.002 inches with a three degree minimum draft, and the heavy textured zone  43  may have an average depth of approximately 0.0045 inches with a six and a half degree minimum draft. In versions of those embodiments the depth may be substantially consistent across the width of each of the zones  41 - 43 . In other versions the depth may vary across the width of one or more of the zones  41 - 43 . For example, in some embodiments the depth may increase in each of the zones in relation to the distance away from the substantially texture-free portion  32 . In some embodiments the lightly textured section  41  may have a texture that substantially conforms to Mold-Tech standard 11000, the medium textured zone  42  may have a texture that substantially conforms to Mold-Tech standard 11030, and the heavy textured zone  43  may have a texture that substantially conforms to Mold-Tech standard 11050. 
     The surface of the textured section  40  can be textured in many ways for light scattering or redirecting the light. For example, in some embodiments the texture may be created by an injection mold tool, compression mold tool, or extruded mold tool that is utilized to create the lens and/or the texture on the lens by forming a texture on the surface of the tool. The texture may be created utilizing, for example, an acid-etch and/or bead blast on the tool surface. The amount of time sections of the tool surface are exposed to the acid etching and/or bead blasting will determine the depth of the texture along such sections. Also, for example, in other embodiments prisms, bumps, pits, random roughening, and/or truncated pyramids may be applied to and/or integrated within the surface of the lens  30 . Also, for example, in some embodiments all or portions of the texturing may substantially conform to one or more texturing standards such as, for example, Mold-Tech, Yick Sang, VDI, etc and/or may optionally be created utilizing processes corresponding therewith. Also, for example, in some embodiments a holographic diffuser, microstructure diffuser, and/or other type of diffuser plate may be utilized to create the texture. For example, a holographic diffuser film could be placed inside the lens  30  and/or laminated to the lens  30 . 
     Referring to  FIG. 3 , a top view of the textured lens  30  of  FIG. 1  is illustrated. The lens  30  is planar, is generally rectangular, and is configured to cover a generally rectangular light exit opening  14  of the lighting fixture  10 . In other embodiments the lens may be geometric shapes other than rectangular and/or may be non-planar. The textured section  40  in  FIG. 3  is generally indicated by circles, the size and density of which generally correspond to the degree of texturing. The textured section  40  extends completely around the substantially texture-free section  32  and extends to the edge  31  of the lens  30 . In alternative embodiments the textured section  40  may not extend completely around the substantially texture-free section  32  and/or may not extend to the edge  31 . For example, in some embodiments the textured portion  40  may only extend along one side of the substantially texture-free section  32  and may stop short of the edge  31 . Also, for example, in some embodiments the textured portion  40  may be configured to substantially correspond to a light output distribution emitted by a particular lighting fixture. For example, if a light output distribution is weighted to one side, the textured portion along all or some of that side may be wider, thinner, and/or non-existent. Also, for example, if a light output distribution has two distinct main beams, two separate substantially texture-free portions may be provided, each optionally surrounded by texturing. Also, for example, in some embodiments a texture-free portion may be provided in between the textured portion  40  and the edge  31 . Optionally, such a texture-free portion may transmit minimal light therethrough when utilized in a lighting fixture and/or may be covered by a lip or other structure utilized to retain the lens within a lighting fixture. 
     The depicted substantially texture-free section  32  comprises a substantial majority of the surface area of the lens  30 . In some embodiments the substantially texture-free section  32  may comprise more than ninety percent of the surface area of the lens  30 . The depicted substantially texture-free section  32  also intersects a substantial majority of the light output intensity of the light output emitted by the LEDs  20 R,  20 G,  20 B of lighting fixture  10 . In some embodiments the substantially texture-free section  32  may intersect more than ninety percent of light output intensity of the light output emitted by the LEDs. For example, in some of those embodiments the lighting fixture  10  may emit light having a light output intensity with a substantially normal light output intensity distribution and the substantially texture-free section  32  may intersect the peak of the light output intensity and approximately forty-five percent of the light output intensity on either side of the peak. 
     Referring now to  FIG. 4 , a second embodiment of a lighting fixture  110  is provided with an arcuate textured lens  130 . The lighting fixture  110  is illustrated schematically in  FIG. 4  and includes a housing  112 . The housing  112  retains the lens  130  across a light exit opening  114  of the lighting fixture  110 . The housing  112  also retains a LED-based light source having a multi-die LED  120 . The LED  120  may contain multiple dies emitting unique spectrums of light. Provided on one side of the LED  120  is a reflector  120  that is configured to generally direct light output from the LED  120  that is incident thereon toward the textured lens  130 . 
     Three exemplary light rays  1201 ,  1202 , and  1203  are depicted emanating from the LED  120 . It is understood that the LED  120  will emit many other light rays than those depicted herein, some of which may contact and be redirected by the reflector  120 . The light rays  1201 - 1203  may be emitted from a single die of the LED  120  or may be emitted from multiple dies thereof. Light rays  1201  and  1202  are each directed toward a substantially texture-free portion  132  of the lens  130  and are transmitted therethrough without being substantially scattered. Other light rays will likewise contact the substantially texture-free portion  132  of the lens  130  and be transmitted therethrough without being substantially scattered. The substantially texture-free portion  132  may optionally alter the path of light rays transmitted therethrough depending on one or more factors such as, for example, the index of refraction of the substantially texture-free portion  132 , the incidence angle of the light ray(s), and/or the thickness of the substantially texture-free portion  132 . The light transmitted through the substantially texture-free portion  132  is generally directed toward a main beam portion  103  of an illumination area  102 . The substantially texture-free portion  132  may optionally have a light texturing applied thereto. 
     Light ray  1203  contacts a textured portion  140  of the lens  130  and is transmitted through, and scattered by, the textured portion  140 . The beginning of the textured portion  140  of the lens  130  is generally indicated by imaginary dashed line  141 A and it extends to the edge of the lens  130 . The textured portion  140  is provided peripherally of the substantially texture-free portion  132 , but is only provided along one side thereof toward a bottom edge of the lens  130 . In alternative embodiments the textured portion  140  may additionally or alternatively be provided along the top edge of the lens  130  and/or one or more sides of the lens  130 . Other light rays will contact the textured portion  140  (some after contacting reflector  122  one or more times) and will likewise be transmitted through and scattered by the textured portion  140 . As described herein, the depth of the texturing of textured portion  140  may gradually increase as it moves from dashed line  141 A to the edge of the lens  140 . The textured portion  140  may optionally alter the path of light rays transmitted therethrough (in addition to altering of the path via scattering caused by the texturing) depending on one or more factors such as, for example, the index of refraction of the textured portion  140 , the incidence angle of the light ray(s), and/or the thickness of the textured portion  140 . 
       FIG. 5  illustrates a section view of a portion of the textured lens of  FIG. 4 . The section includes a bottom edge  131  of the lens  130  and is taken along a portion of the textured portion  140  and a portion of the texture-free portion  132 . It is illustrated that the texture-free portion  132  has a substantially smooth texture-free exterior face  134 . The imaginary dashed line  141 A generally represents the beginning of the textured portion  140  and the beginning of a lightly textured section  141  thereof. Dashed line  142 A generally represents the beginning of a medium textured section  142  of the textured portion  140  and dashed line  143 A generally represents the beginning of a heavy textured section  143  of the textured portion  140 . It is illustrated that the degree of texturing increases gradually across each section  141 ,  142 ,  143  as you move outward from the substantially texture-free section  132 . For example, the degree of texturing in lightly textured section  141  is greater close to dashed line  142 A than it is close to dashed line  141 A. Light rays  591 ,  592 ,  593 , are illustrated transmitted through respective sections  141 ,  142 ,  143 . It is illustrated that the degree of scattering of the light rays  591 ,  592 ,  593  increases as the degree of texturing increases. 
     In some embodiments, the degree of texturing may increase linearly across all or portions of textured portion  140 . In other embodiments the degree of texturing may additionally or alternatively increase exponentially and/or vary according to some other function across all or portions of textured portion  140 . In versions of those embodiments the depth may be substantially consistent across the width of each of the zones  141 - 143 . In other versions the depth may vary across the width of one or more of the zones  141 - 143 . The surface of the textured section  140  can be textured in many ways for light scattering or redirecting the light and all or portions of the texturing may conform to one or more texturing standards. 
     In some embodiments, texturing may be applied to only approximately one to two percent of a lens. In some versions of those embodiments the texturing may be applied along the periphery of the lens. In some embodiments texturing may be applied to up to half of the lens. In some versions of those embodiments the texturing may be applied along the periphery of the lens inward. In some embodiments the textured portion of the lens may intersect anywhere from one to fifty percent of a total light output intensity that is incident on a lens. One of ordinary skill in the art, having had the benefit of the present disclosure, will recognize and appreciate that other applications of texturing to a lens may also be implemented utilizing teachings hereof. 
     While several inventive embodiments have been described and illustrated herein, those of ordinary skill in the art will readily envision a variety of other means and/or structures for performing the function and/or obtaining the results and/or one or more of the advantages described herein, and each of such variations and/or modifications is deemed to be within the scope of the inventive embodiments described herein. More generally, those skilled in the art will readily appreciate that all parameters, dimensions, materials, and configurations described herein are meant to be exemplary and that the actual parameters, dimensions, materials, and/or configurations will depend upon the specific application or applications for which the inventive teachings is/are used. Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the specific inventive embodiments described herein. It is, therefore, to be understood that the foregoing embodiments are presented by way of example only and that, within the scope of the appended claims and equivalents thereto, inventive embodiments may be practiced otherwise than as specifically described and claimed. Inventive embodiments of the present disclosure are directed to each individual feature, system, article, material, kit, and/or method described herein. In addition, any combination of two or more such features, systems, articles, materials, kits, and/or methods, if such features, systems, articles, materials, kits, and/or methods are not mutually inconsistent, is included within the inventive scope of the present disclosure. 
     All definitions, as defined and used herein, should be understood to control over dictionary definitions, definitions in documents incorporated by reference, and/or ordinary meanings of the defined terms. 
     The indefinite articles “a” and “an,” as used herein in the specification and in the claims, unless clearly indicated to the contrary, should be understood to mean “at least one.” The phrase “and/or,” as used herein in the specification and in the claims, should be understood to mean “either or both” of the elements so conjoined, i.e., elements that are conjunctively present in some cases and disjunctively present in other cases. Multiple elements listed with “and/or” should be construed in the same fashion, i.e., “one or more” of the elements so conjoined. Other elements may optionally be present other than the elements specifically identified by the “and/or” clause, whether related or unrelated to those elements specifically identified. 
     As used herein in the specification and in the claims, the phrase “at least one,” in reference to a list of one or more elements, should be understood to mean at least one element selected from any one or more of the elements in the list of elements, but not necessarily including at least one of each and every element specifically listed within the list of elements and not excluding any combinations of elements in the list of elements. This definition also allows that elements may optionally be present other than the elements specifically identified within the list of elements to which the phrase “at least one” refers, whether related or unrelated to those elements specifically identified. Thus, as a non-limiting example, “at least one of A and B” (or, equivalently, “at least one of A or B,” or, equivalently “at least one of A and/or B”) can refer, in one embodiment, to at least one, optionally including more than one, A, with no B present (and optionally including elements other than B); in another embodiment, to at least one, optionally including more than one, B, with no A present (and optionally including elements other than A); in yet another embodiment, to at least one, optionally including more than one, A, and at least one, optionally including more than one, B (and optionally including other elements); etc. 
     It should also be understood that, unless clearly indicated to the contrary, in any methods claimed herein that include more than one step or act, the order of the steps or acts of the method is not necessarily limited to the order in which the steps or acts of the method are recited. Further, any reference numerals appearing in parentheses in the claims are merely for convenience and should be interpreted as limiting in any way. 
     In the claims, as well as in the specification above, all transitional phrases such as “comprising,” “including,” “carrying,” “having,” “containing,” “involving,” “holding,” “composed of,” and the like are to be understood to be open-ended, i.e., to mean including but not limited to. Only the transitional phrases “consisting of” and “consisting essentially of” shall be closed or semi-closed transitional phrases, respectively.