Patent Publication Number: US-11393961-B2

Title: Hybrid lens for controlled light distribution

Description:
RELATED APPLICATION DATA 
     The present application is a continuation application of U.S. patent application Ser. No. 16/587,771 filed Sep. 30, 2019 which is a continuation application of U.S. Pat. No. 10,468,566. 
    
    
     FIELD OP THE INVENTION 
     This invention relates to lighting fixtures and, more particularly, to LED lighting fixtures for various common illumination purposes. Still more specifically, this invention relates to the field of lensing for desired LED light distribution in LED lighting fixtures. 
     BACKGROUND OF THE INVENTION 
     In recent years, the use of light-emitting diodes (LEDs) for various common lighting purposes has increased, and this trend has accelerated as advances have been made in LEDs and in LED-array bearing devices, referred to as “LED modules.” Indeed, lighting needs which have primarily been served by fixtures using high-intensity discharge (HID) lamps, alogen lamps, compact florescent light and other light sources are now increasingly beginning to be served by LEDs. Creative work continues in the field of LED development, and also in the field of effectively utilizing, as much of the light emitted from LEDs as possible. 
     As is known, LED “packages,” which typically consist of an LED component (or a cluster of LEDs) on a base with or without a “primary lens,” each have a lens thereover to direct light from the LED package as intended. (Such lens is sometimes referred to as a “secondary” lens when the package with which it is used includes a primary lens.) Development efforts have been made in the field of such lenses, with the intention being to redirect some of the LED-emitted light in a manner forming illumination patterns desired for particular applications. However, such lenses have tended to fall short of the most desirable performance in that some LED-emitted light is lost or produces illuminance distributions which lack desired characteristics such as color and/or intensity uniformity. 
     Typically, some of the light from LEDs is emitted at angles that cause LED-lighting fixtures to provide less than desirable and less than fully efficient illumination patterns. Some prior lenses have been configured to prevent undesirable light from exiting the lens and others to block such light immediately upon its exiting the lens. Even though these configurations were deemed necessary to achieve desired illumination patterns and to prevent so-called lighting “trespass,” they tended to result in lost light and decreased efficiency of LED illuminators. It would be highly desirable to improve efficiency in the use of light emitted by LEDs in lighting fixtures. 
     A typical LED emits light over a wide range of angles such that light from the LED reaches a particular area of the output surface of the lens at somewhat different angles. This has made it very difficult to control direction of such light. It would be desirable to provide improved control of the direction of light exiting such lenses. 
     Trespass lighting can be evaluated by more than just the amount of light emitted in an undesired direction; also to be considered is how far from the desired direction such light is directed. It would be highly beneficial to provide a lighting apparatus which produces a desired illumination pattern with a maximum amount of light emitted toward the space intended to be illuminated, in typical commercial applications. 
     Lighting fixtures, such as sidewalk, roadway and/or parking lot fixtures, often provide high angle lighting distributions for meeting various areal lighting requirements. Lighting fixtures, for example, can provide a Type II distribution suitable for walkways, highway on-ramps and off-ramps as well as other long and narrow corridors. In other embodiments, lighting fixtures can provide a Type III distribution generally employed for roadway lighting and parking lots where a larger area of lighting is required. Alternatively, a Type V lighting distribution can be provided. Type V lighting distribution can be circular or square, having isotropic intensity over all lateral angles. 
     Achieving high angle lighting distributions with acceptable uniformity and limited glare can be difficult. High angle lighting distributions often contain severe bright spots that only exacerbate visual discomfort resulting from fixture glare. Moreover, point sources of high intensity, such as light emitting diodes (LEDs), can provide multiple bright spots over the light emitting face of a fixture. Various optics have been employed to improve luminous uniformity and glare reduction. However, such optics struggle with effectively mixing and spreading light from intense point sources over high distribution angles. 
     SUMMARY OF THE INVENTION 
     This invention is a lens with improved efficiency of distribution of light from a light emitter having an emitter axis and defining an emitter plane. Such improved efficiency of light output from the light emitter is achieved with the inventive lens which is specifically designed for refraction, reflection and useful output of light emitted in directions of the desired illumination. In certain embodiments, the inventive lens directs the great majority of light from the emitter in a preferential-side direction, including light emitted at angles which previously resulted in the loss of such light. Such efficiency of light use is provided only by configuration of the lens. 
     In certain embodiments, the lens has a faceted output region, a smooth output surface and at least one reflective surface which reflects light through total-internal-reflection (TIR) toward the faceted output region. The faceted output region is formed by pairs of transverse surfaces each surface of which redirects the received light to provide a composite illuminance pattern. The lens may further have faceted input surfaces at least partially defining a light-input cavity about the emitter axis. The faceted input region are formed by pairs of transverse surfaces each surface of which redirects the received light. The faceted input surfaces may include surface portions reflecting light through total-internal-reflection (TIR). In some embodiments, the at least one reflective surface at least partially bounds a reflection cavity offset from the light-input cavity. The faceted output surfaces may include major and minor surfaces. The minor surfaces may be formed by transverse surface portions with cross-sectional dimensions smaller than cross-sectional dimensions of transverse surface portions of the major surfaces. 
     The transverse surface portions of the faceted output surfaces may extend to substantially straight intersection regions substantially parallel to each other. The transverse surface portions may extend to substantially curved intersection regions substantially parallel to each other. 
     The inventive lens includes inner and outer surfaces. The inner surface defines an inner cavity about the emitter axis. The inner surface may have the faceted input surfaces being a plurality of transverse inner regions forming inner stepwise discontinuities redirecting light received from the emitter. The outer surface receives redirected emitter light and has the faceted output region of a plurality of transverse outer regions forming outer stepwise surface discontinuities redirecting the received light. In certain embodiments of the inventive lens at least one of the inner and outer surfaces comprising a combination of at least one smooth region and a plurality of transverse regions forming stepwise discontinuities for redirecting received light. In some of such embodiments, the outer surface includes the smooth outer region. The transverse regions forming stepwise discontinuities of the inner surface may be configured to redirect emitter light toward the smooth outer region. At least some of the transverse regions forming stepwise discontinuities may be configured for refraction of the received light. At least some of the transverse regions forming stepwise discontinuities may also be configured for total internal reflection (TIR) of the received light. 
     Certain embodiments of the lens have a secondary surface offset from the inner surface. The secondary surface may be configured for total internal reflection (TIR) of light received from the inner surface. In some embodiments, the secondary surface at least partially bounds a secondary cavity offset from the inner cavity. 
     In certain alternative embodiments, the secondary surface may be part of an exterior surface at least partially surrounding the inner cavity. In some of such alternative embodiments the secondary surface is radially offset from the inner cavity and extends from near the emitter plane away in directions along the emitter axis and sometimes away from the emitter axis. In certain examples of these embodiments of the lens with a surrounding flange, the flange may extend from such exterior secondary surface. 
     The secondary surface may have a plurality of transverse reflecting regions forming reflecting stepwise discontinuities. 
     In each of the inner, outer and reflecting stepwise discontinuities, corresponding adjacent transverse regions may extend to intersection regions which are substantially parallel to adjacent intersection regions. 
     It should be noted that the term “reflective” is used for convenience in describing the transverse regions forming stepwise discontinuities of the secondary surface. In certain examples, some of such transverse regions may be refractive such that at least a portion of the secondary surface passes light through such regions. 
     In some embodiments, the transverse reflecting regions may be substantially planar surfaces or have convex/concave cross-sections. Adjacent transverse reflecting regions may extend to an intersection region which may be a curved line or cross-sectionally concave/convex surface portion. The intersection regions may be longitudinally straight or extend along a curve. Adjacent intersection regions may be substantially parallel to each other. In addition or alternatively, adjacent intersection regions may extend in a direction away from the emitter plane. In some examples, such adjacent intersection regions may also extend away from the emitter axis. 
     A longitudinal direction of least some of the transverse reflecting regions may be parallel to a plane of bilateral symmetry of the lens. 
     It should be appreciated that lenses according to the present invention may have symmetries other than bilateral such as a rotation symmetry, a quad-lateral or other symmetries that achieve desired illumination patter. Depending on the intended illumination pattern, the inventive lens may be shaped without symmetry and have asymmetrical surfaces. 
     In certain embodiments, at least some of the outer stepwise discontinuities are optically aligned over the secondary surface such that light reflected by the secondary surface is received and further redirected by the outer stepwise discontinuities. 
     In at least one of the inner and outer stepwise discontinuities, corresponding adjacent transverse regions extend to intersection regions therebetween. The intersection regions of the inner stepwise discontinuities may be curved regions each adjoining a pair of the transverse inner regions adjacent to each other. The curved merger region can be convex or concave. The transverse regions of the inner and/or outer surfaces may be substantially planar surfaces or have convex/concave cross-sections. Adjacent intersection regions may be substantially parallel to each other. The intersection regions may be straight or curved lines or have convex or concave cross-sections and be longitudinally straight or extend along a curve. The intersection regions may be in planes substantially orthogonal or parallel to the emitter axis. Additionally or alternatively, longitudinal directions of the intersection regions may be substantially orthogonal or parallel to a plane of bilateral symmetry of the lens. 
     Some of the transverse outer regions may slope at different angles. In a pair of adjacent transverse outer regions, at least one of the pair refracts the received light. 
     At least some of the transverse inner regions may be configured for total internal reflection (TIR) of the light received from the emitter. In addition or alternatively, at least some of the transverse inner regions refract the light received from the emitter. 
     In certain embodiments, at least some of the transverse inner regions are non-planar. In some of such embodiments the transverse inner regions proximal to the emitter axis have substantially concave cross-sections in planes substantially orthogonal to the plane of bilateral symmetry of the lens. 
     Some of the transverse inner regions may longitudinally extend along an arc at least partially surrounding the emitter axis. Some or all of such transverse inner regions may have convex/concave cross-sections. Some of the adjacent transverse inner regions may extend to an intersection region that may have a concave/convex cross-section. 
     The inner surface may have a smooth inner region adjacent the inner stepwise discontinuities. 
     In certain embodiments, the transverse inner regions proximal the emitter axis have smaller cross-sectional dimensions than the transverse inner regions distal from  20  the light emitter. 
     The inner surface may have at least two sets of transverse inner regions which form a corresponding number of distinct sets of the inner stepwise discontinuities. 
     The outer surface may include a smooth outer region. In some of such embodiments which also have the inner surface with a plurality of distinct sets of the inner stepwise discontinuities, at least one of the distinct sets of the inner stepwise discontinuities redirects emitter light toward the smooth outer region. 
     Some embodiments of the inventive lens include at least two secondary surface portions each outwardly offset from the inner surface. At least one of such secondary surface portions may be configured for total internal reflection (TIR) of light received from the inner surface. 
     In certain embodiments, the secondary surface portions are separate surfaces substantially opposite each other. Additionally or alternatively, the secondary surface portions may be connected at corners. In some examples, the inventive lens may have three and more secondary surface portions. In some of such examples, the secondary surface portions are connected at corners and form polygonal shapes corresponding to the number of the secondary surface portions. In some alternative examples, at least some of the plurality of the secondary surface portions are separate from the adjacent secondary surface portions. Is some other examples, there may be a combination of the separate and connected secondary surface portions. Yet in some alternative examples, the secondary surface portions may form a substantially annular secondary surface around the inner cavity. Additionally or alternatively, such substantially annular secondary surface may be continuous or have interruptions. 
     In some of such embodiments, the outer surface comprises cuter stepwise discontinuities corresponding to each of the secondary surface portions for receiving and further redirecting light received from the corresponding secondary surface portion. 
     At least one of the secondary surface portions comprises a plurality of transverse reflecting regions forming reflecting stepwise discontinuities. 
     In certain embodiments, the outer surface comprises at least two sets of transverse outer regions forming a corresponding number of distinct outer stepwise discontinuities. At least one of such distinct outer stepwise discontinuities is outward of the other for receiving light reflected or otherwise redirected by corresponding regions of the corresponding secondary surface. 
     In some of such embodiments, at least two of the distinct outer stepwise discontinuities are optically aligned over each of the secondary surface portions. 
     The sets of outer stepwise discontinuities formed by transverse outer regions may be substantially planar surfaces and may also extend to intersection regions that may be straight or curved lines or be surface portions cross-sectionally planar or convex/concave. Some or all of the intersection regions may be substantially parallel to each other. Some or all of the intersection regions may be generally in planes substantially orthogonal or parallel to the emitter axis. Such general planes of the intersection regions of the outer stepwise discontinuities may be orthogonal or parallel to a plane of bilateral symmetry of the lens. 
     The outwardmost of the sets of the outer stepwise discontinuities may be formed by transverse outer regions with smaller cross-sectional dimensions in axially-parallel planes than cross-sectional dimensions of the transverse outer regions of the other set(s) of the outer stepwise discontinuities which is/are closer to the emitter axis than the outwardmost set of the outer stepwise discontinuities. In some embodiments, the outwardmost setts) of the outer stepwise discontinuities may be formed by a greater number of transverse outer regions. 
     In another aspect of this invention, the lens(es) according to this invention is optically coupled to an LED light source of art LED arrangement supported by an LED light fixture. In certain examples, the LED light fixture has a heat-sink structure having a mounting surface supporting the LED arrangement. The LED arrangement may include a plurality of spaced apart LED light sources and a plurality of the lenses each optically coupled with a corresponding one of the light sources. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an enlarged opaque perspective view from a light-output side of one embodiment the inventive lens, 
         FIG. 2  is an enlarged opaque perspective view from a light-input side of the lens of  FIG. 1 . 
         FIG. 3  is an enlarged opaque light-output plan view of the lens of  FIG. 1 . 
         FIG. 4  is an enlarged opaque light-input plan view of the lens of  FIG. 1 . 
         FIG. 5  is an enlarged opaque perspective cross-sectional view from a light-input side of the lens of  FIG. 1 , taken along a plane of bilateral symmetry of the lens. 
         FIG. 6  is an enlarged opaque perspective cross-sectional view generally from a light-output side of the lens of  FIG. 1 , taken along a plane of bilateral symmetry of the lens. 
         FIG. 7  is an enlarged opaque cross-sectional view of the lens of  FIG. 1 , shown in the plane of bilateral symmetry of the lens. 
         FIGS. 8 and 9  are enlarged opaque views of opposite lateral sides of the lens of  FIG. 1 . 
         FIG. 10  is an enlarged opaque front (preferential side) view of the lens of  FIG. 1 . 
         FIG. 11  is an enlarged opaque back (non-preferential side  5 ) view of the lens of  FIG. 1 . 
         FIG. 12  is an enlarged simplified representation with ray-fan simulation showing light distribution achieved with the lens of  FIG. 1  primarily in the plane of bilateral symmetry of the lens. 
         FIG. 13  is an enlarged simplified representation with ray-fan simulation showing light distribution achieved with the lens of  FIG. 1  in planes orthogonal the plane of bilateral symmetry of the lens. 
         FIGS. 14-16  are exemplary representations of simulated illuminance achieved with the lens of  FIG. 1 . 
         FIG. 17  is an exemplary representation of a simulated intensity distribution achieved with the lens of FIG. 
         FIG. 18  is an exemplary representation of a simulated candela plot achieved with the lens of  FIG. 1 , graph  1  showing a vertical plane such as a plane including or substantially parallel to the emitter axis, graph  2  showing a horizontal cone. 
         FIG. 19  is an exemplary representation of a simulated light distribution pattern achieved on an exemplary working plane with luminaries utilizing the lens of  25   FIG. 1 . 
         FIG. 20  is an exemplary representations of simulated chromaticity showing a color uniformity achieved with the lens of  FIG. 1 . 
         FIG. 21  is another enlarged opaque cross-sectional view of the lens of  FIG. 1 , shown from an opposite side of the view in  FIG. 7 . 
         FIG. 22  is a light-output side perspective view illustrating thickness analysis of the lens of  FIG. 1 . 
         FIG. 23  is a simulated lit rendering or an illuminated near-field appearance of the lens shown in  FIG. 1 , representing areas that would appear lit or bright when viewing the lens directly to illustrate the lens spreading the light over a larger area, leading to reduced near-field glare. 
         FIG. 24  is an enlarged opaque cross-sectional lateral side view of a prior lens not utilizing stepwise discontinuities of the surfaces of the inventive lens. 
         FIG. 25  is a light-output side perspective view illustrating thickness analysis of the lens of  FIG. 24 , for comparison with  FIG. 23 , lightest areas represent local thickness in excess of 4 mm. 
         FIG. 26  is a simulated lit rendering or an illuminated near-field appearance of the lens shown in  FIGS. 24 and 25 , representing areas that would appear it, or bright when viewing the lens directly, to show comparison with the inventive lens illustrated in  FIG. 23 . 
         FIG. 27  is an enlarged simplified representation with ray-fan simulation showing light distribution achieved with the lens of  FIGS. 24-26  primarily in the plane of bilateral symmetry of the lens. 
         FIG. 28  is an enlarged simplified representation with ray-fan simulation showing light distribution achieved with the lens of  FIG. 24-27  in planes orthogonal the plane of bilateral symmetry of the lens. 
         FIG. 29  is an enlarged transparent perspective view from a light-output side of the lens of  FIG. 25 . 
         FIG. 30  is an enlarged transparent plan view of the lens of  FIG. 29 . 
         FIG. 31  is an enlarged opaque perspective view from a light-output side of the lens of  FIG. 29 . 
         FIG. 32  is an enlarged opaque perspective view from a light-input side of the lens of  FIG. 29 . 
         FIG. 33  is another enlarged opaque cross-sectional view of the lens of  FIGS. 25-32 , shown from an opposite side of the view in  FIG. 24 . 
         FIG. 34  is an enlarged transparent lateral side view of the lens of  FIGS. 24-33 . 
         FIGS. 35-37  are exemplary representations of simulated illuminance achieved with the lens of  FIG. 31 . 
         FIG. 38  is an exemplary representation of a simulated intensity distribution achieved with the lens of  FIG. 31 . 
         FIG. 39  is an exemplary representation of a simulated candela plot achieved with the lens of  FIG. 31 , graph  1  showing a vertical plane such as a plane including or substantially parallel to the emitter axis, graph  2  showing a horizontal cone. 
         FIG. 40  is an exemplary representation of a simulated light distribution pattern achieved on an exemplary working plane with luminaries utilizing the lens of  FIG. 31 . 
         FIG. 41  is an exemplary representations of simulated chromaticity showing a color uniformity achieved with the lens of  FIG. 31 . 
         FIG. 42  is an enlarged opaque perspective view from a light-output side of another embodiment of the inventive lens. 
         FIG. 43  is an enlarged opaque perspective view from a light-input side of the lens of  FIG. 42 . 
         FIG. 44  is an enlarged transparent perspective view from a light-output side of the lens of  FIG. 42 . 
         FIG. 45  is an enlarged simplified representation with ray-fan simulation showing light distribution achieved with the lens of  FIG. 42  primarily in the plane of bilateral symmetry of the lens. 
         FIG. 46  is an exemplary representations of simulated illuminance achieved with the lens of  FIG. 42 . 
         FIG. 47  is an enlarged opaque perspective view from a light-output side of another embodiment the inventive lens. 
         FIG. 48  is an enlarged opaque perspective view from a light-input side of the lens of  FIG. 47 . 
         FIG. 49  is an enlarged opaque light-output plan view of the lens of  FIG. 47 . 
         FIG. 50  is an enlarged opaque light-input plan view of the lens of  30   FIG. 47 . 
         FIG. 51  is an enlarged opaque perspective cross-sectional view from a light-input side of the lens of  FIG. 47 , taken along a plane of bilateral symmetry of the lens. 
         FIG. 52  is an enlarged opaque cross-sectional view of the lens of  FIG. 47 , shown in the plane of bilateral symmetry of the lens. 
         FIGS. 53 and 54  are enlarged opaque views of opposite lateral sides of the lens of  FIG. 47 . 
         FIG. 55  is an enlarged opaque front (preferential side) view of the lens of  FIG. 47 . 
         FIG. 56  is an enlarged opaque back (non-preferential side  5 ) view of the lens of  FIG. 47 . 
         FIG. 57  is an enlarged simplified representation with ray-fan simulation showing light distribution achieved primarily in the plane of bilateral symmetry of the lens with a lens having some characteristics of input and output surfaces of the lens of  15   FIG. 47 . 
         FIG. 58  is an enlarged simplified representation with ray-fan simulation showing light distribution achieved in planes orthogonal the plane of bilateral symmetry of the lens with the lens of  FIG. 57 . 
         FIGS. 59-61  are exemplary representations of simulated illuminance achieved with the lens of  FIG. 47 . 
         FIG. 62  is an exemplary representation of a simulated intensity distribution achieved with the lens of  FIG. 47 . 
         FIG. 63  is an exemplary representation of a simulated candela plot achieved with the lens of  FIG. 47 , graph  1  showing a vertical plane such as a plane including or substantially parallel to the emitter axis, graph  2  showing a horizontal cone. 
         FIG. 64  is an exemplary representation of a simulated light distribution pattern achieved on an exemplary working plane with luminaries utilizing the lens of  FIG. 47 . 
         FIG. 65  is an exemplary representations of simulated chromaticity showing a color uniformity achieved with the lens of  FIG. 47 . 
         FIG. 66  is an enlarged opaque perspective view from a light-output side of yet another embodiment the inventive lens. 
         FIG. 67  is an enlarged opaque perspective view from a light-input side of the lens of  FIG. 66 . 
         FIG. 68  is an enlarged opaque light-output plan view of the lens of  FIG. 66 . 
         FIG. 69  is an enlarged opaque light-input plan view of the lens of  FIG. 66 . 
         FIG. 70  is an enlarged opaque perspective cross-sectional view from a light-input side of the lens of  FIG. 66 , taken along a plane of bilateral symmetry of the lens. 
         FIG. 71  is an enlarged opaque perspective cross-sectional view from a light-output side of the lens of  FIG. 66 , taken along a plane of bilateral symmetry of the lens. 
         FIG. 72  is an enlarged opaque cross-sectional view of the lens of  FIG. 66 , shown in the plane of bilateral symmetry of the lens. 
         FIGS. 73 and 74  are enlarged opaque views of opposite sides along the plane of bilateral symmetry of the lens of  FIG. 66 . 
         FIGS. 75 and 76  are enlarged opaque views of opposite sides substantially orthogonal to the plane of bilateral symmetry of the lens of  FIG. 66 . 
         FIG. 77  is an enlarged simplified representation with ray-fan simulation showing light distribution achieved with one example of a lens similar to that of  FIG. 66  and having substantially planar transverse inner regions. 
         FIG. 78  is an enlarged simplified representation with ray-fan simulation showing light distribution achieved in planes orthogonal the plane of bilateral symmetry with the lens of  FIG. 77 . 
         FIG. 79  is an exemplary representation of simulated illuminance achieved with the lens having the type of inner-surface configuration of the lens shown in  FIGS. 77 and 78 . 
         FIG. 80  is an exemplary representations of simulated chromaticity showing a color uniformity achieved with the lens of  FIGS. 77 and 78 . 
         FIG. 81  is an enlarged opaque cross-sectional view of the lens of  FIGS. 77 and 78 , shown in the plane substantially orthogonal to the plane of bilateral symmetry of the lens. 
         FIG. 82  is an enlarged opaque cross-sectional view of the lens of  FIG. 66 , shown substantially orthogonal to the plane of bilateral symmetry of the lens. 
         FIG. 83  is an enlarged axially-adjacent fragment of the opaque cross-sectional view of  FIG. 82 , showing axially-adjacent transverse inner regions having substantially concave cross-sections. 
         FIG. 84  is an enlarged simplified representation with ray-fan simulation showing light distribution achieved with the lens of  FIG. 66  in planes substantially parallel to the plane of bilateral symmetry of the lens. 
         FIG. 85  is an enlarged simplified representation with ray-fan simulation showing light distribution achieved with the lens of  FIGS. 66 and 82  in planes orthogonal to the plane of bilateral symmetry. 
         FIG. 86  is an enlarged simplified representation with ray-fan simulation showing light distribution achieved with the lens of  FIGS. 66 and 82  in planes substantially orthogonal the plane of bilateral symmetry, showing light output at major outer stepwise discontinuities of the outer surface. 
         FIG. 87  is an enlarged simplified representation with ray-fan simulation showing light distribution achieved with the lens of  FIGS. 66 and 82  in planes substantially parallel the plane of bilateral symmetry, showing light output at major outer stepwise discontinuities of the outer surface. 
         FIG. 88  is an enlarged simplified representation with ray-fan simulation showing light distribution achieved with the lens of  FIGS. 66 and 82  in planes substantially orthogonal the plane of bilateral symmetry, showing light output at minor outer stepwise discontinuities outward of the major outer stepwise discontinuities of the outer surface. 
         FIG. 89  is an enlarged simplified representation with ray-fan simulation showing light distribution achieved with the lens of  FIGS. 66 and 82  in planes substantially parallel the plane of bilateral symmetry, showing light output at minor outer stepwise discontinuities outward of the major outer stepwise discontinuities of the outer surface. 
         FIG. 90  is an enlarged simplified representation with ray-fan simulation showing light distribution achieved with the lens of  FIGS. 66 and 82  in planes substantially parallel the plane of bilateral symmetry, showing light output at smooth outer region  35 D of outer surface  30 D. 
         FIG. 91  is an enlarged simplified representation with ray-fan simulation showing light distribution achieved with the lens of  FIGS. 66 and 82  in planes substantially orthogonal the plane of bilateral symmetry, showing light output at smooth outer region  35 D of outer surface  30 D. 
         FIGS. 92-94  are exemplary representations of simulated illuminance achieved with the lens of  FIGS. 66 and 82 . 
         FIG. 95  is an exemplary representation of a simulated intensity distribution achieved with the lens of  FIGS. 66 and 82 . 
         FIG. 96  is an exemplary representation of a simulated candela plot achieved with the lens of  FIGS. 66 and 82 , graph  1  showing a vertical plane such as a plane including or substantially parallel to the emitter axis, graph  2  showing a horizontal cone. 
         FIG. 97  is an exemplary representation of a simulated light distribution pattern achieved on an exemplary working plane with luminaries utilizing the lens of  FIGS. 66 and 82 . 
         FIG. 98  is an exemplary representations of simulated chromaticity showing a color uniformity achieved with the lens of  FIGS. 66 and 82 . 
         FIG. 99  is an enlarged simplified representation with ray-fan simulation showing light distribution achieved with another exemplary embodiment of a lens according to the present invention in planes substantially parallel the plane of bilateral symmetry of such lens. 
         FIG. 100  is an exemplary representation of a simulated illuminance achieved with the lens of  FIG. 99 . 
         FIG. 101  is an exemplary representation of simulated chromaticity showing a color uniformity achieved with the lens of  FIG. 99 . 
         FIG. 102  is a perspective view from a light-output side of an example of a light Fixture utilizing a pair of LED-array modules each having a plurality of lenses of the type shown in  FIG. 1 . 
         FIG. 103  is a fragment of  FIG. 102  showing an LED arrangement at a greater scale. 
         FIG. 104  is a fragment of the LED arrangement of  FIG. 103  at a greater scale. 
         FIG. 105  is a fragmentary perspective view showing a plurality of inventive lenses each optically coupled with a corresponding one of LED light sources supported on a circuit board. 
         FIG. 106  is a perspective view from a light-output side of an exemplary LED-array module. 
         FIG. 107  is a plan view from a light-output side of an example of a light fixture utilizing the LED-array module of the type shown in  FIG. 106 . 
         FIG. 108  is a fragmentary perspective view from a light-output side of the light fixture of  FIG. 107 . 
         FIG. 109  is a greatly enlarged example of stepwise surface discontinuities with sharp intersection regions. 
         FIG. 110  is a greatly enlarged example of stepwise surface discontinuities with concave (“fillets”) and convex (“rounding”) intersection regions. 
         FIG. 111  is a much enlarged fragment of  FIG. 110 . 
         FIG. 112  is an enlarged perspective view of one example of an LED package and including an array of eight LEDs on a submount and an asymmetric primary lens overmolded over the LED array. 
         FIG. 113  is an enlarged perspective view of another example of an LED package and including an array of forty-eight LEDs on a submount and an asymmetric primary lens overmolded over the LED array. 
         FIG. 114  is an enlarged perspective of yet another example of an LED package which has a single LED on a submount with a hemispheric primary lens overmolded over the LED. 
         FIG. 115  is an enlarged side view of the LED package of  FIG. 114 . 
         FIG. 116  is an enlarged top view of the LED package of  FIG. 114 . 
         FIG. 117  is an enlarged top view of another exemplary LED package including an array of four LEDs on a submount and a hemispheric primary lens overmolded over the LED array such that the axis of the primary lens is offset from the axis of the LED array. 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
       FIGS. 1-23 and 42-97  illustrate embodiments of lens  10  according to the present invention. Lens  10  has an improved efficiency of distribution of light from a light emitter  12  having an emitter axis  14  and defining an emitter plane  15 . In embodiments shown in  FIGS. 1-23 and 42-65 , lenses  10 A,  10 B,  10 C and  10 D direct the great majority of light from emitter  12  in a preferential-side direction  4 , including light emitted at angles which previously resulted in the loss of such light. 
     Lens  10  includes an inner surface  20  and an outer surface  30 . Inner surface  20  extends from emitter plane  15  defines an inner cavity  21  about emitter axis  14 . Inner surface  20  has a plurality of transverse inner regions  22  forming inner stepwise discontinuities  23  redirecting light received from emitter  12 . 
     Outer surface  30  receives redirected emitter light and has a plurality of transverse outer regions  32  forming outer stepwise discontinuities  33  redirecting the received light. In illustrated embodiments, lens  10  has a secondary surface  40  offset from inner surface  20 . As best seen in  FIGS. 12, 45, 73, 80, 83 and 85 , secondary surface  40  is configured for total internal reflection (TIR) of light received from the inner surface  20 . 
     In some of the illustrated embodiments of lens  10 , secondary surface  40  at least partially bounds a secondary cavity  41  offset from inner cavity  21 .  FIGS. 5-7  illustrate secondary cavity  41 A being further bound by a rear surface  45  of a rear wall  450  with a flange  46  extending outwardly therefrom for securing lens  10 A with respect to light emitter  12 . 
     In lens  10 C illustrated in  FIGS. 47-58 , secondary surface  40 C has a plurality of transverse reflecting regions  42  forming reflecting stepwise discontinuities  43 . The primary purpose of such TIR features is to re-direct high-angle light from the light source  12  to a more vertical direction (e.g., closer to parallel to the optic axis  14  or source surface-normal). This ‘upward’ light may be re-directed or spread into a lateral direction (e.g., parallel to the roadway) by adding facets to the adjacent surface such as outer stepwise discontinuities  33  above the TIR reflector, or by adding facets to the TIR surface itself (reflecting stepwise discontinuities  43 ), or any combination thereof. 
     “Faceted,” “step-like” or “Fresnel-like” surfaces, as used herein, refer to surface regions formed by a plurality of planar or curved surface portions each extending along a plane or a curve, respectively, which intersects with a plane or a curve of an adjacent planar or curved surface portion. Some of the adjacent planes or curves intersect with unequal slopes. As described further in this section, certain embodiments include curved merger regions between adjacent planar or curved surface portions. Such curved merger regions serve to smooth intersections between adjacent surface portions. 
       FIGS. 48 and 50  show lens  10 C having a third stepwise discontinuity  233 C rearwardly bounding inner cavity  21 C and extending from emitter-adjacent surface  27 C away from emitter plane  15  toward transverse inner regions  222 C. 
       FIGS. 3, 4, 42, 49, 50, 68 and 69  show that in inner stepwise discontinuities  23 , in outer stepwise discontinuities  33  and in reflecting stepwise discontinuities  43  pairs of adjacent transverse regions extend to corresponding inner intersection regions  24 , outer intersection regions  34  and reflective intersection regions  44  which are substantially parallel to adjacent intersection regions  24 ,  34 ,  44 . In illustrated lens embodiment  10 C, transverse reflecting regions  42 C have convex/concave cross-sections best seen in  FIGS. 51 and 52 ,  FIGS. 48, 50 and 51  show adjacent transverse reflecting regions  42 C extending to an intersection region  44 C which is a curved line. Adjacent intersection regions  44 C are shown substantially parallel to each other and extend in a direction away from emitter plane  15  and away from emitter axis  14 , as also seen in  FIGS. 51 and 52 .  FIG. 50  farther shows a longitudinal direction of transverse reflecting regions  42 C being parallel to a plane  16  of bilateral symmetry of lens  10 C. 
     In illustrated lens embodiments  10 A and  10 D, each of outer stepwise discontinuities  33 A,  33 D is optically aligned over corresponding secondary surface  40 A,  40 D such that light reflected by secondary surface  40 A,  40 D is received and further redirected by Outer stepwise discontinuities  33 A,  33 D. 
       FIGS. 3-4, 49-50, and 68-69  show intersection regions  24  of inner stepwise discontinuities  23  as curved regions each adjoining a pair of transverse inner regions  22  adjacent to each other.  FIGS. 2, 4 and 5 and 48, 50 and 51  show intersection regions  24 A,  24 C curved about emitter axis  14  in planes substantially orthogonal to emitter axis  14  and plane  16  of bilateral symmetry of lens  10 A,  10 C and substantially parallel emitter plane  15 .  FIGS. 2, 4 and 48 and 50  illustrate transverse inner regions  223 A,  223 C longitudinally arcing partially around emitter axis  14 . 
       FIGS. 67, 68 and 70-72  show intersection regions  24 D curved in planes substantially transverse emitter plane  15  and substantially parallel plane  16  of bilateral symmetry of lens  10 . 
     The addition of faceted surfaces such as inner stepwise discontinuities may introduce sharp angles that can result in non-uniformities such as visible lines or striations in brightness and/or color in the resulting illuminance patterns seen in  FIGS. 79 and 80 . These non-uniformities can be compared to more smoothly varying analogue surfaces in conventional lenses, an example of which is illustrated in  FIGS. 24-37 . 
     In order to reduce such non-uniformities, a slight curvature may be added to the facet surfaces to spread out the light.  FIGS. 82 and 83  show substantially concave transverse inner regions  224 D proximal emitter axis  14 . 
     Other approaches for ‘smoothing out’ intensity or color artifacts may include adding slight ripples to various surfaces, or adding slight roughness. Additionally, in order to reduce the impact of light incident on the surface from opposite edges of the source and to reduce visual artifacts, it is helpful to reduce the size and to modify the geometry of the transverse regions directly above light emitter  12  such as an LED component. 
       FIGS. 77-85  illustrate a comparison of an example of linear sharp intersections between transverse regions ( FIG. 81 ) in a lens  10 D′ and lens  10 D with facets providing improved illuminance and color uniformity ( FIGS. 82 and 83 ) which have a slight curvature to the facets, rounded facet corners, and reduced size of the facets directly over light emitter  12 . 
     Intersection regions  24 ,  34 ,  44  may be concave merger regions  71  or convex merger regions  72 . In addition or alternatively, intersection regions  24 ,  34 ,  44  may be longitudinally straight or extend along a curve. 
     The addition of cross-sectional curvature, such as concave merger regions  71  may also be referred to as “fillets.” And convex merger regions  72  may be described as a ‘rounding’ of the sharp facet edges. The “fillets” and “rounding” of the sharp facet edges, as seen in  FIGS. 109-111 , may facilitate reducing far-field illuminance artifacts. In addition, such fillets and rounding of the sharp edges facilitates standard manufacturing processes such as injection molding due to machining constraints and the desire to minimize stress-concentration features. Intentionally increasing the radius of such fillets above what is required for manufacturing can allow further ‘smoothing’ of illuminance patterns. 
       FIGS. 12, 13, 78 and 85  show transverse inner regions  22  refracting the light received from emitter  12 . 
       FIGS. 48 and 50-52  illustrate inner surface  20 C which has a smooth inner region  25 C adjacent inner stepwise discontinuities  23 C. 
       FIGS. 2, 4-7 and 48 and 50-52  show lens embodiments  10 A and  10 C with inner surface  20 A,  20 C having two sets of transverse inner regions  221 A,  222 A and  221 C,  222 C which form a corresponding number of distinct sets of the inner stepwise discontinuities  231 A,  232 A and  231 C,  232 C, respectively. 
       FIGS. 78 and 85  illustrate pairs of adjacent transverse outer regions  32 D with one transverse outer region  321 D of the pair refracts the received light and the other transverse outer region  322 D of the pair reflects the received light through TIR. 
       FIGS. 1, 3, 5-9, 47, 49, 51-54, 66, 68 and 70-74  show outer surface  30 A,  30 C,  30 D including a smooth outer region  35 A,  35 C,  35 D.  FIG. 12  shows that, in lens  10 A, distinct set  231 A of inner stepwise discontinuities  23 A redirects emitter light toward smooth outer region  35 A. 
     The use of input coupling facets (transverse inner regions  22 ) combined with an output free-form surface (smooth outer region  35 ) facilitates direction of the light into a desired illuminance pattern.  FIGS. 90 and 91  show the simulated ray-fan illustrating the combined effect of the input facets and output free-form surface to spread the light. Both the input facets (transverse inner regions  22 D) and the output free-form surface (smooth outer region  35 D) utilize primarily refraction to re-direct the light into the desired pattern. Alternately or additionally, some or all of the input facets may utilize TIR to re-direct light. The free-form surface (smooth outer region  35 ) could also comprise a geometric surface such as an ellipse, a cylinder, etc. depending on the desired output illuminance profile. 
       FIGS. 67, 69, 70-74 and 77  illustrate lens  10 D which includes two secondary surface portions  40 D which are separate surfaces substantially opposite each other and each outwardly offset from inner surface  20 D.  FIG. 77  best illustrates secondary surface portions  40 D being configured for total internal reflection (TIR) of light received from inner surface  20 D. 
     The use of opposing TIR reflectors (secondary surfaces  40 ) is beneficial in achieving a narrow light distribution, as in the case of a Type II roadway optic. This feature has distinct advantages over typical optics for this application that utilize a single TIR reflector (secondary surface  40 ) in combination with a free-form surface (smooth outer region  35 ) in that the opposing TIR reflectors  40 D serve to effectively limit the light to the desired narrow hand, with little light ‘overflow’ or loss. An example of this feature in lens  10 D (shown in  FIGS. 66-74 ) can be compared to the single-sided TIR feature  40 A of lens  10 A (shown in  FIGS. 1-9 ). Some embodiments of this inventive feature may have three or more TIR reflectors arranged in a triangular, square, rectangular, hexagonal or other arrangement. Such arrangements would be useful for creating symmetric or asymmetric distributions where it is important to limit the ‘overflow’ of light beyond specific boundaries such as roadway curbs or to reduce glare due to high-angle light. Correspondingly, a single TIR surface elongated into a circular, elliptical, semicircular, semi-elliptical, parabolic, etc. profile may be desired to create more rounded illuminance distributions. Certain exemplary embodiments may use four linear or curved TIR surfaces arranged in a square pattern (connected at the corners or separate at the corners), or a circular TIR ring to create a Type V symmetric illuminance distribution for roadways or area lighting. 
       FIGS. 66-74  show outer surface  30 D including outer stepwise discontinuities  33 D corresponding to each of secondary surface portions  40 D for receiving and further redirecting light received from the corresponding secondary surface portion, as illustrated in  FIGS. 77, 84, 87 and 89 . 
       FIGS. 66, 68 and 71-74  show outer surface  30 D having two sets of transverse outer regions  323  and  324  forming a corresponding number of distinct outer stepwise discontinuities  331  and  332 . Outer stepwise discontinuity  331  is outward of outer stepwise discontinuity  332 . Each of outer stepwise discontinuities  331  and  332  are optically aligned over each of secondary surface portions  40 D for receiving light reflected or otherwise redirected by corresponding regions of corresponding secondary surface  40 D, as shown in  FIGS. 77, 84, 87 and 89 . 
       FIGS. 84-89  illustrate how the present invention utilizes sets  323  and  324  of facets positioned directly above a TIR reflector formed by secondary surface  400  which serve to expand light laterally along the roadway parallel to the curb. In this arrangement, the TIR reflector re-directs the light ‘upward’ towards the facets as shown in  FIGS. 86-89 . Each facet has two sides (also referred to as transverse outer regions  32 D) sloped at different angles for spreading the light laterally along the roadway. 
     In traditional Fresnel facets, one side of the facet is usually intended to not interact strongly with the light (typically oriented nearly parallel to the incident rays so as to minimize light loss in unintended directions). Due to fabrication limitations such as the need to avoid ‘undercuts’, this ‘invisible’ facet generally interacts with some light rays and has a negative impact on performance. 
     In the inventive lens, with the described inventive facet orientation also shown in  FIGS. 66, 71, 85, 86 and 88 , both sides (transverse outer regions  32 D) of each facet redirect light onto the roadway and thus may b wally active with minimal loss. The use of two separate sets of facets at different positions with respect to emitter axis  14 , as further shown in  FIGS. 66, 68, 71 and 86-89 , may ensure that the maximum local thickness of lens  10 D above TIR reflector  40 D does not exceed the thickness desired for a single-shot molding as mentioned above. 
     Individual facets (transverse regions  32 D) may have a linear profile, or a curved profile to improve illuminance uniformity and color mixing. Additionally or alternatively, the facets may comprise a linear or ‘straight’ extruded element—transverse outer regions  323 , or they may comprise a ‘swept’ element where the path of extrusion is curved (as is the case for the input facets—transverse inner regions  22 D, seen in  FIGS. 70-72 ) or segmented (e.g., each segment having an differing angular path) to provide additional light control or mixing. 
       FIGS. 86-89  illustrate simulated ray paths showing lateral light spreading with minimal loss by a set of major facets (stepwise discontinuity  331 ) and minor facets (outwardmost outer stepwise discontinuity  332 ) positioned above the TIR reflector secondary surface  40 D) and oriented such the ridges (intersecting regions  34 D) are perpendicular to the ‘curb’ of the roadway. 
       FIGS. 66, 68, 71, 86 and 88 , show sets  331  and  332  of outer stepwise discontinuities  33 D as substantially planar surfaces which extend to straight intersection regions  34 D parallel to each other and extending in planes substantially parallel to plane  16  of bilateral symmetry of lens  10 D. 
     As best seen in  FIGS. 66 and 68 , outwardmost set  331  of outer stepwise discontinuities  331 D is shown to be formed by transverse outer regions  323  which in axially-parallel planes orthogonal to plane  16  has cross-sectional dimensions smaller cross-sectional dimensions of transverse outer regions  323  of set  324  of the outer stepwise discontinuities  332 D which is closer to emitter axis  12  than outwardmost set  331  of the outer stepwise discontinuities  331 D. Outwardmost set  331  of outer stepwise discontinuities  331 D is also shown to be formed by a greater number of transverse outer regions  324 . 
     In summary, the present invention utilizes a “hybrid” combination to faceted Fresnel-like surfaces, surfaces configured for total-internal-reflection (TIR), and smooth surfaces (e.g., parabolic, elliptical, free-form, etc.) to create complex illuminance distributions such as those required for streetlight illumination. The term “smooth,” as used herein with respect to lens surfaces, means having an even and regular surface or consistency free from facets, discontinuities and perceptible projections, lumps or indentations. Smooth surface can be, e.g., parabolic, elliptical, cylindrical, free-form etc. 
     Potential advantages of the present invention include a low profile, more compact lens geometry for applications with space constraints. 
       FIGS. 42-45  show lens  10 B which can viewed in comparison of the Fresnel-like surfaces in some aspects of the inventive lens with more traditional geometric surfaces (such as parabolas) of lens  10 P shown in  FIGS. 24-28 . Lens  10 B has been ‘collapsed’ down to more 2-dimensional structures which occupy less volume.  FIGS. 27, 28 and 45  present a simplified representation with ray-fan simulations showing similar light distributions achieved with a conventional geometric lens  10 P and a thinner, low profile “collapsed” Hybrid lens  10 B. Another advantage of the present invention is simplified, reduced cost fabrication. The incorporation of Fresnel-like surfaces can enable lenses with a maximum local thickness of less than 4 mm, and preferably less than 3 mm. This allows for simplified, less costly ‘single-shot’ molding processes compared to lenses with thicker regions that are subject to slumping and shrinkage, thus requiring multiple molding steps or ‘shots’ to build up the structure to the final desired dimensions while maintaining surface fidelity and tolerance. This is particularly beneficial in cases where larger LED components (˜&gt;3 mm) are used, as overall lens dimensions typically scale with source size. 
       FIGS. 21, 22, 24 and 25  illustrate a comparison between a conventional geometric streetlight lens  10 P (shown in  FIGS. 24-37 ) and the inventive lens  10 A incorporating the invention, with associated thickness analysis seen in  FIGS. 22 and 25  with the lightest regions being higher thickness. White regions in  FIG. 25  represent local thickness in excess of 4 mm. 
     Another advantage of the present invention is an improved optical performance. The incorporation of additional, simplified control surfaces (e.g., ‘collapsing’ a parabolic surface into a series of linear facets—transverse regions forming stepwise discontinuities) facilitates simplifying of the lens-design process by allowing optimization of each sequential and separate lens surface. This leads to improved lens designs with better optical efficiency and ore control over illuminance distributions resulting in improved performance in the final application. Still another advantage of the present invention is an improved color uniformity. Many LED light sources/components do not have uniform color emission over all angles. For example, many LED components emit significantly ‘yellower’ light at high angles. This can cause undesirable color artifacts (e.g. yellowish streaks or striations visible on illuminated surfaces such as roadways). The combination of faceted surfaces with smooth surfaces facilitates improved control and mixing of light emitted at various angles (with corresponding color variances). 
     Yet another advantage of the present invention is a near-field glare reduction. Faceted Fresnel-like surfaces of the stepwise discontinuities facilitate the effect of ‘spreading out’ light emitted from a small source such as an LED component so as to make it appear that the light is coining from a larger area, leading to reduced near-field glare. 
       FIGS. 23 and 26  illustrate simulated renderings of inventive lens  10 A (shown in  FIG. 23 ) and prior lens  10 P (shown in  FIG. 26 ) comparing the ‘lit’ or illuminated near-field appearance of prior lens  10 P and inventive hybrid lens  10 A described earlier in this disclosure. The lighter regions represent areas that would appear lit or bright when viewing the lens directly. The inventive hybrid lens  10 A spreads the light over a larger area, leading to reduced near-field glare. 
     In certain instances of the present invention, the faceted surface may be a unique addition of one or more facets to an existing smooth surface with the intent of, for example, directing light to a specific direction, improving illuminance uniformity, or mixing light rays emitted by the LED source at different angles to reduce color artifacts clue to inherent color-angle-non-uniformity of some sources. Each individual facet (also referred herein as a surface of one of a plurality of transverse regions) may serve to re-direct light using primarily TIR or refraction. In some cases, the facet may be designed to intentionally utilize both TIR and refraction, depending on the angle of incidence of the incoming light rays. 
       FIG. 77  illustrates an example of an addition of a single facet of outer surface  30 D formed by two transverse outer regions  325  extending at smooth outer region  35 D substantially orthogonally to plane  16  of bilateral symmetry of lens  10 D.  FIG. 77  also shows that optical coupling of lens  10 D is such that one of two TIR surfaces  40 D is disposed closer to emitter axis the opposite TIR surface  40 . The single facet  325  is proximal to that TIR surface  40  which is farther from emitter axis  14 . 
       FIGS. 102-108  show examples of LED light fixtures  100 A and  100 B, each of which has a heat-sink structure  110  having a mounting surface  111  supporting an LED arrangement  120 .  FIGS. 105 and 106  best illustrate an exemplary LED arrangement  120  having an LED-array module  121  which has a plurality of lenses  10  each optically coupled to an LED light source  12  supported on a circuit board  11 . In the illustrated embodiments, LED arrangement  120  also has a frame member  17  securing lenses  10  according to the present invention with respect to circuit board  11  and the corresponding light emitters  12 . 
       FIGS. 102-104  show an exemplary light fixture  100 A utilizing two LED-array modules  121 A supported on heat sink  110 A.  FIGS. 107 and 108  show an exemplary light fixture  100 B utilizing one LED-array module  121 B supported on heat sink  110 A. Heat sink  110  is shown extending from a housing portion  130  which forms a closed chamber  131 . Fixture  100  is shown to have venting apertures  140  permitting air and water flow through the fixture for convection cooling of heat-dissipating regions of heat-sink  110  which conducts heat away from mounting surface  111  receiving heat from circuit board  11  during operation of LED arrangement  120 . 
       FIGS. 112-117  the show light emitter in the form of an LED package  230  which has a primary lens  240  over the at least one LED  220 . In such embodiments, the inventive lens is a secondary lens placed over primary lens  240 . The light emitter may be of the type illustrated in  FIGS. 114-116  which show LED package  230 D with single LED  220  on a submount  260  and hemispheric primary lens  240 D coaxially overmolded on submount  260  over LED  220 . 
       FIGS. 112 and 113  illustrate exemplary LED packages  230 A and  230 B each including an array of LEDs  220  on an LED-populated area  250  which has an aspect ratio greater than 1, and primary lens  240  being overmolded on a submount  260  over LED-populated area  250 . It is seen in  FIG. 113  that the array may include LEDs  220  emitting different-wavelength light of different colors such as including red LEDs along with light green or other colors to achieve natural white light. Light emitters of the type as LED packages  230 A and  230 B are described in detail in application Ser. No. 13/441,558, filed on Apr. 6, 2012, and in application Ser. No. 13/441,620, filed on Apr. 6, 2012. The contents of both applications are incorporated herein by reference in their entirety. 
       FIGS. 112, 113 and 117  illustrate versions of the LED light emitter configured to refract LED-emitted light in a forward direction (i.e., toward preferential side P). In each LED package  230 A,  230 B and  230 C, each LED array defines an emitter axis.  FIGS. 112 and 113  illustrate primary lens  240 A configured to refract LED-emitted light forward.  FIG. 117  shows hemispheric primary lens  240 C having a centerline  240  offset from the emitter axis  14 . It should be understood that for higher efficiency, the LED emitter may have a primary lens having both its centerline offset from the emitter axis and also being shaped for refraction of LED-emitted light toward preferential side P. In  FIGS. 112 and 113 , primary lens  240 A is shown as asymmetric. 
     Lenses described herein can assist in providing Type II, Type III or Type V lighting distributions from luminaries. Accordingly, luminaries comprising lenses according to the present invention can be used in a variety of outdoor lighting applications including, but not limited to, sidewalk lighting as well as roadway and parking lot lighting. Luminaries comprising lenses according to the present invention described herein can also be employed in several indoor lighting applications. For example, luminaire can provide illumination to narrow spaces, such as aisles, hallways and/or corners of a building or house. Indoor applications also include wall washing. An asymmetric lighting distribution provided by a luminaire can illuminate surfaces of one or more walls. In some embodiments, for example, multiple walls illuminated by the luminaire intersect to form a corner. In other embodiments, multiple walls face one another such as in a hallway or corridor. In some embodiments, light fixtures are mounted on the ceiling or recessed into the ceiling, for wall illumination. Alternatively, the light fixtures can be mounted on the floor or recessed into the floor for wall illumination according to methods described herein. As described herein, high angle or lateral lighting distributions can be provided by luminaries comprising lenses described herein. The lighting distributions can be asymmetric or symmetric in nature. In some embodiments, lighting distributions provided by luminaries comprising optic assemblies have peak intensity at angles greater than 30 degrees relative to nadir. Peak intensity of a lighting distribution provided by light fixtures described herein can also have one or more values selected from Table II. 
     
       
         
           
               
             
               
                 TABLE II 
               
               
                   
               
               
                 Peak Intensity of Lateral Lighting Distribution Relative to Nadir 
               
               
                   
               
             
            
               
                 &gt;40 
               
               
                 &gt;50 
               
               
                 &gt;60 
               
               
                 &gt;70 
               
               
                 &gt;80 
               
               
                 30-85 
               
               
                 40-85 
               
               
                 50-70 
               
               
                 50-85 
               
               
                 60-85 
               
               
                   
               
            
           
         
       
     
     Luminaries can also comprise light redirection optics in addition to or in place of optic assemblies. Luminaries, for example, can comprise light redirection optics comprising total internal reflection facets of Fresnel architecture as well as refractive surfaces, including those illustrated in the figures. Light redirection optics can also have any design to provide lighting distributions similar to or the same as lenses described herein. 
     LED light sources may comprise packaged LED chip(s) or unpackaged LED chip(s). LED elements or modules can use LEDs of the same or different types and/or configurations. The LEDs, for example, can be monochromatic or any desired color combination. The LEDs can comprise single or multiple phosphor-converted white and/or color LEDs, and/or bare LED chip(s) mounted separately or together on a single substrate or package that comprises, for example, at least one phosphor-coated LED chip either alone or in combination with at least one color LED chip, such as a green LED, a yellow LED, a red LED, etc. The LED module can comprise phosphor-converted white or color LED chips and/or bare LED chips of the same or different colors mounted directly on a printed circuit board (e.g., chip on board) and/or packaged phosphor-converted white or color LEDs mounted on the printed circuit board, such as a metal core printed circuit board or FR4 board. In some embodiments, the LEDs can be mounted directly to a heat sink or another type of board or substrate. Depending on the embodiment, LED arrangements or lighting arrangements using remote phosphor technology can be employed as would be understood by one of ordinary skill in art, and examples of remote phosphor technology are described in U.S. Pat. No. 7,614,759, assigned to the assignee of the present invention and hereby incorporated by reference. 
     In those cases where a soft white illumination with improved color rendering is to be produced, each LED element or module or a plurality of such elements or modules may include one or more blue shifted yellow LEDs and one or more red or red/orange LEDs as described in U.S. Pat. No. 7,213,940, assigned to the assignee of the present invention and hereby incorporated by reference. The LEDs may be disposed in different configurations and/or layouts along one or more edges of the waveguide body, as desired. Different color temperatures and appearances could be produced using other LED combinations of single and/or multiple LED chips packaged into discrete packages and/or directly mounted to a printed circuit board as a chip-on board arrangement. 
     In one embodiment, the light sources can comprise any LED, for example, XP-Q LED incorporating TrueWhite® LED technology or as disclosed in U.S. patent application Ser. No. 13/649,067, filed Oct. 10, 2012, entitled “LED Package with Multiple Element Light Source and Encapsulant Having Planar Surfaces” by Lowes et al., the disclosure of which is hereby incorporated by reference herein, as developed and manufactured by Cree, Inc., the assignee of the present application. In another embodiment, the light sources can comprise XQ-E LEDs developed by Cree, Inc. 
     Any of the embodiments disclosed herein incorporating LED light sources may include power or driver circuitry having a buck regulator, a boost regulator, a buck-boost regulator, a fly-hack converter, a SEPIC power supply or the like and/or multiple stage power converter employing the like, and may comprise a driver circuit as disclosed in U.S. patent application Ser. No. 14/291,829, filed May 30, 2014, entitled “High Efficiency Driver Circuit with Fast Response” by Hu et al. or U.S. patent application Ser. No. 14/292,001, filed May 30, 2014, entitled “SEPIC Driver Circuit with Low Input Current Ripple” by Hu et al. incorporated by reference herein. The circuit may further be used with light control circuitry that controls color temperature of any of the embodiments disclosed herein, such as disclosed in U.S. patent application Ser. No. 14/292,286, filed May 30, 2014, entitled “Lighting Fixture Providing Variable CCT” by Pope et al. incorporated by reference herein. 
     Various embodiments of the invention have been described in fulfillment of the various objects of the invention. It should be recognized that these embodiments are merely illustrative of the principles of the present invention. Numerous modifications and adaptations thereof will be readily apparent to those skilled in the art without departing from the spirit and scope of the invention. 
     While the principles of the invention have been shown and described in connection with specific embodiments, it is to be understood that such embodiments are by way of example and are not limiting.