CA2965932A1 - Quiet-ceiling light fixture systems and methods - Google Patents

Abstract

A light fixture includes a housing having sidewalls that define a manifold aperture, extending from upper to lower edges of the manifold aperture. The housing includes first coupling features. The light fixture includes at least one adapter plate with second coupling features that removably couple with the first coupling features. The adapter plate defines an adapter plate aperture. At least one light emitting engine removably couples with the adapter plate such that emitted light passes through the adapter plate aperture. The light fixture further includes a baffle that includes at least one baffle cell. The baffle cell includes an upper baffle edge, defining an upper baffle aperture through which light emitted by the at least one light engine passes, a lower baffle edge, defining an output aperture for the emitted light, and a baffle cell wall that extends from the upper baffle edge to the lower baffle edge.

Description

QUIET-CEILING LIGHT FIXTURE SYSTEMS AND METHODS
BACKGROUND
[0001] Luminaires for interior lighting are often designed for aesthetic appeal when directly viewed, as well as for providing high quality illumination. Related design objectives can include providing visually interesting components such as a housing and/or other structural components or light scattering or diffusing type elements. Typically, the actual light-emitting devices within luminaires are more or less exempt from such design objectives, because viewers generally will not be looking directly into the light-emitting devices due to discomfort.
However, other elements within fixtures can provide visual interest as well as shielding viewers from high-angle light output (glare). Certain other features often present in luminaires, but which may be regarded as distracting, include optical surfaces that form angles. Optical performance typically changes noticeably across such angles such that a viewer's eye is drawn to them, instead of the luminaire simply providing gradually or continuously changing luminous intensity across the visible area of the luminaire.
SUMMARY

[0002] Quiet-ceiling light fixture systems and methods herein recognize the advantages of providing a visually "quiet" ceiling, that is, harsh light may be limited to low angles so that distant light fixtures do not present glare, while for human viewers directly underneath the light fixtures, eyebrows block glare of the direct beam. The light fixtures herein also recognize the advantages of providing fully adjustable and field reconfigurable lighting modules in small housings.

[0003] In an embodiment, a light fixture includes a manifold housing having sidewalls that define a manifold aperture. The sidewalls extend from one or more upper edges of the manifold aperture to a lower edge of the manifold aperture. A first dimension of the manifold aperture defines an axial direction, and a second dimension of the manifold aperture defines a lateral direction. The manifold includes first coupling features. The light fixture also includes at least one adapter plate including second coupling features. The second coupling features of the adapter plate removably couple with the first coupling features of the manifold housing to secure the at least one adapter plate to the manifold housing. The adapter plate defines an adapter plate ' aperture. At least one light engine emits light and removably couples with the at least one adapter plate such that light emitted by the at least one light engine passes through the adapter plate aperture. The light fixture further includes a baffle that substantially spans the manifold aperture and comprises at least one baffle cell. The baffle cell includes (i) an upper baffle edge that defines an upper baffle aperture through which light emitted by the at least one light engine passes, (ii) a lower baffle edge that defines an output aperture for the emitted light, and (iii) a baffle cell wall that extends from the upper baffle edge to the lower baffle edge.

[0004] In an embodiment, a baffle for use in a light fixture that includes one or more light emitter positions, includes one or more upper edges, each of the upper edges encircling a light emitting aperture for one of the light emitter positions. Each point of the upper edges lies within an upper region, and plan view shapes of the upper edges form closed shapes that are devoid of angles. The baffle also includes one or more lower edges, each of the one or more lower edges encircling an output aperture for one of the light emitter positions. Each point of the one or more lower edges lies within a lower region, and plan view shapes of the lower edges form closed shapes that are devoid of angles. The baffle further includes an interior baffle surface that extends downwardly from each of the upper edges to the lower edges. The interior baffle surface is continuously and downwardly concave from each of the upper edges to each of the lower edges, and is devoid of angles.

[0005] In an embodiment, a retainer ring for a light fixture includes a cylindrical main body section that defines a cylindrical axis, and an inner retaining flange that extends radially inward from a distal end of the main body section. The inner retaining flange extends substantially about a circumference of the distal end. A proximal end of the main body section includes one or more coupling features that extend radially inward from the proximal end.

[0006] A method of field reconfiguring a light fixture that is mounted within an aperture of a surface includes disengaging from the surface at least one spring clip that retains a housing of the light fixture within the aperture, and removing the housing from the aperture. The method also includes decoupling a first light engine from the housing, electrically decoupling the first light engine from a driver electronics box, and electrically coupling a second light engine with the driver electronics box. The method further includes coupling the second light engine with , I
the housing, replacing the housing into the aperture, and re-engaging the spring clip with the surface to retain the housing within the aperture.

[0007] In an embodiment, a method of generating a surface profile for a light fixture baffle, the method includes defining an upper edge for the baffle and defining a lower edge for the baffle. A plan view shape of the upper edge is a first closed shape that lies within a first region and is devoid of angles. The closed shape defines a centroid. A plan view shape of the lower edge is a second closed shape that is devoid of angles, and lies within a second region.
The method also includes defining a first side profile that is devoid of angles, and connects the upper edge with the lower edge at a first azimuthal angle about the centroid.
The method further includes defining a second side profile that that is devoid of angles, and connects the upper edge with the lower edge at a second azimuthal angle offset from the first azimuthal angle. The method further includes interpolating side profiles from the first side profile to the second side profile, along all azimuthal angles between the first azimuthal angle and the second azimuthal angle, so as to form the baffle surface profile. The baffle surface profile transitions smoothly from the first side profile at the first azimuthal angle to the second side profile at the second azimuthal angle.
BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Embodiments are described in detail below with reference to the following figures, in which like numerals within the drawings and mentioned herein represent substantially identical structural elements.

[0009] FIG. 1 is a schematic perspective view of an interior space illuminated by a set of quiet-ceiling light fixtures, according to one or more embodiments.

[0010] FIG. 2A is a bottom plan schematic view illustrating a quiet-ceiling light fixture having two light engines, according to an embodiment.

[0011] FIG. 2B is a bottom plan schematic view illustrating a quiet-ceiling light fixture having three light engines, according to an embodiment.

[0012] FIG. 3A is a schematic, upward looking, exploded isometric view of the quiet-ceiling light fixture of FIG. 2B, illustrating a mounting surface with an aperture into which the light fixture may be installed, according to an embodiment.

I
,

[0013] FIG. 3B is a schematic side elevation of the quiet-ceiling light fixture of FIG. 2B.

[0014] FIG. 3C is a schematic cross-sectional drawing of the quiet-ceiling light fixture of FIG. 2B.

[0015] FIG. 4A is a schematic side elevation of the quiet-ceiling light fixture of FIG. 2A.

[0016] FIG. 4B is a schematic cross-sectional view of the quiet-ceiling light fixture of FIG. 2A, taken along the axial direction at a lateral midpoint thereof.

[0017] FIG. 5A is a schematic, upward looking isometric view of a quiet-ceiling light fixture, according to an embodiment.

[0018] FIG. 5B is a front view of the quiet-ceiling light fixture of FIG. 5A.

[0019] FIG. 5C is a schematic cross-sectional drawing of the quiet-ceiling light fixture of FIG. 5A.

[0020] FIG. 6A is a schematic side view of a baffle of the quiet-ceiling light fixture of FIG. 2B, according to an embodiment.

[0021] FIG. 6B is a schematic, upward looking bottom plan view of the baffle of FIG.
6A.

[0022] FIG. 6C is a schematic, downward looking top plan view of the baffle of FIG. 6A.

[0023] FIG. 6D is a schematic, downward looking cross-section of the baffle of FIG. 6A, at about two-thirds of the height of the baffle.

[0024] FIG. 6E is a schematic, downward looking cross-section of the baffle of FIG. 6A, at about one-third of the height of the baffle.

[0025] FIG. 6F is a schematic, cross-sectional view of the baffle of FIG. 6A, taken at lines 6F-6F in FIG. 6B.

[0026] FIG. 6G is a schematic, cross-sectional view of the baffle of FIG. 6A, taken at lines 6G-6G in FIG. 6B.

[0027] FIG. 7 is a flowchart illustrating a method for generating a prescription for the surface profile for a baffle, in accord with an embodiment.

[0028] FIG. 8, illustrates, in isometric view, a light fixture that integrates a variety of accessories, in accord with an embodiment.

[0029] FIG. 9 illustrates, in an exploded view, the light fixture of FIG. 8.

[0030] FIG. 10A illustrates, in a first isometric view, a retainer ring for a quiet-ceiling light fixture, in accord with an embodiment.

[0031] FIG. 10B illustrates, in a second isometric view, the retainer ring of FIG. 10A.

[0032] FIG. 11A illustrates, in a first isometric view, a kicker reflector for a quiet-ceiling light fixture, in accord with an embodiment.

[0033] FIG. 11B illustrates, in a second isometric view, the kicker reflector FIG. 11A.

[0034] FIG. 11B illustrates, in a side view, the kicker reflector of FIG. 11A.
DETAILED DESCRIPTION

[0035] The subject matter of embodiments of the present invention is described here with specificity to meet statutory requirements, but this description is not intended to limit the scope of the claims. The claimed subject matter may be embodied in other ways, may include different elements or steps, and may be used in conjunction with other existing or future technologies. This description should not be interpreted as implying any particular order or arrangement among or between various steps or elements except when the order of individual steps or arrangement of elements is explicitly described. Each example is provided by way of illustration and/or explanation, and not as a limitation. For instance, features illustrated or described as part of one embodiment may be used on another embodiment to yield a further embodiment. Upon reading and comprehending the present disclosure, one of ordinary skill in the art will readily conceive many equivalents, extensions, and alternatives to the specific, disclosed luminaire types, all of which are within the scope of embodiments herein.

[0036] Quiet-ceiling light fixture systems and methods are disclosed according to various embodiments. Certain embodiments provide light fixtures that are compact and provide a visually "quiet" ceiling, that is, direct views of light engines therein are obscured at high angles (for example, but not limited to, angles over about 55 degrees from nadir, when ceiling mounted), such that the light sources provide targeted illumination only toward low angles (for example, but not limited to, angles less than about 55 degrees from nadir, when ceiling mounted). Between nadir and 55 degrees is sometimes considered a useful range for light because directly under a light fixture, the human eyebrow acts as a natural glare shield, but when viewed from a distance, light over 55 degrees from nadir is not shielded and becomes unwanted glare. Individual fixtures provide one or more individual light sources that may be fixed or adjustable, that is, the light source may be tilted in polar angle, and/or rotated in azimuthal angle, according to needs at a given location. The light sources are field-reconfigurable using methods discussed herein. Certain embodiments feature hardware that enables re-configurability by providing a retainer ring that may be disassembled from below the fixture to add, remove and/or replace components, such as optical accessories. The retainer ring itself may be formed so as to include optical features (for example, certain of the optical features may be integrally molded with the retainer ring). Certain of these embodiments, and others, can also be customized through the use of interchangeable adapter plates, each of which provides mechanical support for a specific type of light engine and/or other lighting related hardware, such as sensors, communication devices and the like.

[0037] In the following description, positional terms like "above," "below,"
"vertical,"
"horizontal" and the like are sometimes used to aid in understanding features shown in the drawings as presented, that is, in the orientation in which labels of the drawings read normally.
These meanings are adhered to, notwithstanding that light fixtures herein may be mounted to surfaces that are not horizontal.

[0038] FIG. 1 is a schematic perspective view illustrating an interior space 2 illuminated by quiet-ceiling light fixtures 102 and 103, according to embodiments. FIGS.
2A and 2B are bottom plan schematic views illustrating light fixtures 102 and 103, respectively. In FIG. 1, a ceiling 5 is used as a mounting surface for light fixtures 102, 103, but this is not required; light fixtures herein may mount with other surfaces such as walls 15, floor 10 or any other available surface.

[0039] As shown in FIGS. 2A and 2B, light fixtures 102 include two light engines 110, while light fixtures 103 include three light engines 110. Each light fixture 102 includes a baffle 122 and a trim ring 132, while light fixture 103 includes a baffle 123 and a trim ring 133.

[0040] Referring back to FIG. 1, light engines 110 are shown within light fixtures 102 and 103, but are not labeled for clarity of the drawing. However, a broken line extends from a center of light emission for each light engine 110, illustrating a center beam path of light from the corresponding light engine 110. Broken lines for different ones of light engines 110 are shown extending in different directions, illustrating the adjustability of light engines 110 within each light fixture 102, 103. As described further below, light engines 110 may be fixed or may be adjustable in polar and/or azimuthal angle, either before or after installation. Width of the light beams can be also adjusted before or after installation by replacing optics of light engines 110 and/or adding or deleting accessories to light engines 110. In FIG. 1, it can be seen that if the broken lines shown indicate centers of light beams having half-angles of about 55 degrees, all of floor 10 shown in FIG. 1 will be reasonably well illuminated, as will portions of walls 15.

[0041] Light fixtures herein may include adapter plates that couple with housings disposed therein to provide structural support for light engines 110 and/or other lighting related devices. Adapter plates and baffles may couple with one another through complementary attachment points so that the adapter plates can be exchanged as necessary, before or after installation, to support a desired light engine 110. In some embodiments, adapter plates provide apertures for corresponding light engines 110 to emit light through, while in other embodiments, an adapter plate provides mechanical support for a light engine 110 that is situated partially or completely below the adapter plate. In some of these and in other embodiments, adapter plates provide mechanical support for other lighting related devices, and do not necessarily form apertures. In still other embodiments, adapter plates simply close off an associated light engine position in which no light engine 110 or other lighting related device is to be installed. A
universal adapter plate may be provided that can support a variety of different types of light engines. In other embodiments, however, adapter plates are designed to couple with a particular light engine.

[0042] Light engines 110 herein may be fixed or adjustable. When adjustable, light engines 110 may be mechanically adjustable in tilt and/or azimuthal angle.
Adjustable light engines 110 may also include mechanisms for shaping (e.g., collimating, focusing, defocusing and the like) light produced therein. Both fixed and adjustable light engines 110 may include optics that may be removable and replaceable with different optics that have compatible form factors, but provide different light shaping. Both fixed and adjustable light engines 110 may also include features to allow coupling and/or removal of accessories such as collimating shields, glare shields, diffusers, kicker reflectors and others. Light engines 110 may either connect to standard electrical power (e.g., 110/120VAC) that is controlled externally, or connect with a power supply that in turn provides power that is customized by type (e.g., low voltage DC) and is controlled to regulate light supplied by the light engines. Light engines 110 advantageously generate light using light-emitting diodes (LEDs) in order to provide high light output and low heat generation in a small physical size that can cooperate with compact optics. Exemplary embodiments of housings, baffles, attachment points, light engines and other features of quiet-ceiling light fixtures are now discussed.

[0043] FIG. 3A is a schematic, upward looking, exploded isometric view of quiet-ceiling light fixture 103, illustrating a mounting surface 7 with an aperture 23 into which light fixture 103 may be installed. Mounting surface 7 that forms aperture 23 may be, for example, ceiling 5 (FIG. 1) but may also be any other structure, such as a wall. FIG. 3B is a schematic side elevation of light fixture 103. FIG. 3C is a schematic cross- sectional view of light fixture 103, taken at line 3C-3C in FIG. 3A. Each of FIGS. 3A, 3B and 3C provides axes denoting vertical (Z), axial (A) and lateral (L) directions as applicable to each drawing.

[0044] Quiet-ceiling light fixture 103 includes a housing 143 that couples with mounting surface 7 using spring clips 145. Trim ring 133 can be unsnapped and removed from housing 143, and with trim ring 133 removed, spring clips 145 can be accessed so as to decouple spring clips 145 from mounting surface 7. Advantageously, both removal of trim ring 133 and decoupling of spring clips 145 can be performed from an illustrated underside 106 of light fixture 103. With spring clips 145 so decoupled, light fixture 103 can drop from (or be pulled out of) mounting surface 7 in order to install and/or field reconfigure light fixture 103. A baffle 123 couples with housing 143 at attachment points 153. Advantageously, with trim ring 133 removed, baffle 123 can also be accessed from underside 106 to decouple baffle 123 from housing 143 to install light fixture 103, and/or reconfigure light fixture 103 after installation, as discussed further below. Although not shown in the drawings for clarity of illustration, an optional cover plate may be retained by trim ring 133 to cover all or a portion of the output aperture of the light fixture 103. The cover plate can be made of any material that permits light to exit the fixture 103. The cover plate may also provide features such as a diffusing surface, backlit signage and the like.

[0045] In FIGS. 3A, 3B and 3C, both housing 143 and baffle 123 define three light engine positions 111, as shown. Because housing 143 supports multiple light engine positions 111, housing 143 and other housings herein are sometimes referred to as "manifold housings."
However, the term "manifold housing" herein is not intended to mean only such housings that define or encompass only one light engine position. In FIGS. 3A, 3B and 3C, each light engine position 111 is occupied by a light engine 110-1, but light fixture 103 can be configured to use other types of light engines 110, as discussed below. Adapter plates 150-1 that are configured to support light engine 110-1 at coupling features 144 that couple with housing 143 at complementary coupling features 148 of housing 143 (not labeled in FIGS. 3A, 3B and 3C for clarity of illustration; see FIG. 12). Each adapter plate 150-1 forms an aperture 160-1 sized for its associated light engine 110-1 to transmit light therethrough. Light engine positions 111 are separated by a spacing that is sufficient to provide clearance for adjustable light engines 110-1 to rotate (e.g., up to about 360 degrees azimuthally in some embodiments) without interfering with one another, as discussed below. Baffle 123 includes coupling features 188 (see FIGS 6A, 6B) at each light engine position 111 for coupling with housing 143.

[0046] Baffle 123 is configured so as to form a high angle glare shield between adjacent light engines 110. In some embodiments, baffle 123 is configured such that along axial direction A of light fixture 103, baffle 123 blocks light from each light engine 110-1 that is emitted at a vertical angle greater than 55 degrees from nadir. Similarly, trim ring 133 blocks light from each light engine 110-1 that is emitted at a vertical angle greater than 55 degrees from nadir in the lateral direction L, such that light fixture 103 is glare free (e.g., emits no significant light at angles above about 55 degrees) in any direction. Baffle 123 can be configured to provide further aesthetic benefits, as described further below.

[0047] FIG. 4A is a schematic side elevation of quiet-ceiling light fixture 102. FIG. 4B
is a schematic cross-sectional view taken along the axial direction at a lateral midpoint of fixture 102. Each of FIGS. 4A and 4B provides axes denoting the vertical (Z) and axial (A) directions.

[0048] Light fixture 102 includes the same functionality as light fixture 103 except that only two light engine positions 111 are present, with two light engines 110-1 mounted therein.

Baffle 122, trim ring 132 and housing 142 that encompass the length of light fixture 102 are similar but different (e.g., shorter) elements than the corresponding elements of light fixture 103.
However, light engines 110-1, coupling features 144, spring clips 145 and adapter plates 150-1 with apertures 160-1 therein are identical to the same features illustrated in light fixture 103, FIGS. 3A, 3B and 3C.

[0049] FIG. 5A is a schematic, upward looking isometric view of a quiet-ceiling light fixture 101, which is similar to light fixtures 102, 103. FIG. 5B is a front view of quiet-ceiling light fixture 101, and FIG. 5C is a schematic cross-sectional drawing of quiet-ceiling light fixture 101 taken along line 5C-5C in FIG. 5A. Each of FIGS. 5A, 5B and 5C provides axes denoting vertical (Z), axial (A) and lateral (L) directions as applicable to each drawing.

[0050] Light fixture 101 includes similar functionality as light fixtures 102 and 103. In light fixture 101, only one light engine position 111 is present, with one light engine 110-1 mounted therein. Light fixture 101 may also include other structural differences as compared with, for example, light fixtures 102, 103. For example, in the embodiment illustrated in FIG.
5A, housing 141 (and associated trim ring 131) is square in plan outline, with baffle 121 being circular in cross section (e.g., a truncated cone). Other embodiments may be rectangular in plan outline, with an associated baffle being a version of baffles 122 or 123 cut down to support a single instance of light engine 110-1. In the illustrated embodiment, light engine 110-1 couples directly with housing 141, using no adapter plate. Housing 101 thus forms an emission aperture 160-2 for light from light engine 110-1 at light engine position 111, instead of the emission aperture being formed in an adapter plate. In other embodiments, however, an adapter plate may be used with light fixture 101. Quiet-ceiling light fixture 101 includes a housing 141 that couples with a mounting surface using spring clips 145, in similar manner as light fixtures 102, 103.

[0051] FIG. 6A is a schematic side view of baffle 123 of quiet-ceiling light fixture 103.
FIG. 6B is a schematic, upward looking bottom plan view of baffle 123. FIG. 6C
is a schematic, downward looking top plan view of baffle 123. FIG. 6D is a schematic, downward looking cross-section of baffle 123, at about two-thirds of the height of baffle 123.
FIG. 6E is a schematic, downward looking cross-section of baffle 123, at about one-third of the height of baffle 123. FIG. 6F and FIG. 6G are schematic, cross-sectional views of baffle 123, taken at lines 6F-6F and 6G-6G, respectively, in FIG. 6B. Each of FIGS. 6A through 6G
provides axes denoting vertical (Z), axial (A) and lateral (L) directions, as applicable to each drawing. Also indicated is a direction of an azimuthal angle 0, useful in discussing geometries of each light engine position 111 relative to a centroid 189 of each light engine position 111.

[0052] The illustrated baffle 123 demonstrates several useful geometric features that should be understood as but one example of a baffle embodiment herein. Baffle 123 spans three light engine positions 111 and defines three baffle cells ¨ one for each light engine position 111.
Although the illustrated shape of each baffle cell of baffle 123 is identical for each light engine position 111, other embodiments are possible in which the baffle cells of baffle 123 differ in shape among light engine positions. An aperture 197 extends through baffle 123 at each baffle cell or light engine position 111, centered about a centroid 189 of each cell or light engine position 111, as illustrated; each aperture 197 provides clearance for emission of light from an associated light engine 110 (e.g., as shown in FIGS. 1 through 5C). Bounding each baffle cell are an upper edge 190, a lower edge 191 and an interior baffle surface 192 that extends from upper edge 190 to lower edge 191. Upper edge 190 lies within an upper region 194, and lower edge 191 lies within a lower region 195 that are planes in FIG. 6G, although upper region 194 and lower region 195 may not be planes in other embodiments. Lower edges 191 of adjacent baffle cells meet to form dividers 193, as illustrated. Dividers 193 thus extend in the lateral direction, axially midway between adjacent cells of baffle 123. By blocking high angle light, dividers 193 help to reduce glare from light sources positioned above baffle 123, especially in the axial direction, as discussed above. It can be seen by comparing FIG. 6C, a top plan view, with FIGS. 6D and 6E, which are cross-sectional views at increasing depth within baffle 123, that aperture 197 is round at upper edge 190 of baffle 123. Aperture 197 then widens and begins to take on a rectangular aspect as the cross-sectional plane proceeds downward through baffle 123, but aperture 197 does not form angles at any depth, including at lower edge 191, best seen in bottom plan view FIG. 6B. FIGS. 6A and 6B also label coupling features 188, which couple baffle 123 with housing 143 by seating within attachment points 153 (see FIGS.
3A, 3B, 4A) to improve mechanical stability of light fixture 103.

[0053] Advantageously, at each light engine position 111, interior baffle surface 192 is continuously and downwardly concave from upper edge 190 to lower edge 191. For example, FIGS. 6F and 6G illustrate axial side profiles 198 and lateral side profiles 199 respectively.

Axial side profile 198 and lateral side profile 199 are continuously and downwardly concave, meet upper edge 190 at their upper ends, and meet lower edge 191 at their lower ends. Also advantageously, as illustrated in FIGS. 6B through 6E, plan view shapes of upper edges 190 and lower edges 191 are configured to be devoid of angles. "Plan view shapes"
herein refers to an inner border or each of the physical upper and lower edges, in a horizontal plane. This excludes any angles that may be formed in vertical directions such as angles formed by the top or bottom surface of the baffle where it intersects the side profile. Plan view shapes also mean that upper or lower edges that lie in non-planar regions 194, 195 would be evaluated based on their projection to a horizontal plane (which is moot when regions 194, 195 are already in horizontal planes, as illustrated in FIGS. 6F, 6G).

[0054] Thus, when plan view shapes are considered, although upper edges 190 and lower edges 191 may have straight segments, all corners or angles between such segments are rounded, with the additional condition that the rounded corners deviate smoothly from the straight segments. This condition can also be described as plan view shapes of each of upper edges 190 and lower edges 191 being mathematically smooth within their respective planes (e.g., each respective edge 190, 191 has a continuous derivative with respect to azimuthal angle 0, at any angle 0). In the embodiment shown, each of upper edges 190 is a circle, but this is not required.

[0055] When plan view shapes of upper edges 190 and lower edges 191 are devoid of angles, interior baffle surface 192 can also be configured to be devoid of angles. Because interior baffle surface 192 acts as a reflector in certain embodiments, having interior baffle surface 192 be devoid of angles avoids the distracting effect of seeing light that is "trapped" at any such angles, or other effects where optical performance changes noticeably at the angle.
That is, interior baffle surface 192 will not present visually distracting, fixed features; instead, light reflected by interior baffle surface 192 will move continuously according to changes in angle of view. By providing rounded corners such that plan view shapes of upper edges 190 and lower edges 191 are devoid of angles, baffles can be designed so as to provide fixtures that are rectangular in outline, and have substantially rectangular light engine positions (e.g., light engine positions 111 discussed above) with quiet-ceiling characteristics.
"Substantially rectangular"
means herein a closed shape that includes four side segments, a first two of the side segments being parallel to and spaced apart from one another by a first distance, the second two of the side segments being straight, parallel to and spaced apart from one another by a second distance, and oriented at a ninety degree angle with respect the first two side segments, the side segments being joined by corner segments that are not straight lines, such that the first two straight side segments have a length of at least half the second distance, and the second two straight side segments have a length of at least half the first distance.

[0056] Referring to FIG. 7, a method 200 for generating a surface profile for a baffle (e.g., interior baffle surface 192) is illustrated. An upper edge for the baffle is defined in a first step 205. The upper edge forms an upper closed shape that lies within a first region (e.g., upper region 194, FIG. 6G), and a plan view shape of the upper edge is devoid of angles. The upper edge defines a centroid (e.g., centroid 189, FIG. 6G). A lower edge for the baffle is defined in step 210. The lower edge forms a lower closed shape that lies within a second region (e.g., lower region 195, FIG. 6G) that is separated from the first region by a vertical spacing (e.g., height H, FIG. 6G), and a plan view shape of the lower edge is devoid of angles. A first side profile is defined in step 215. The first side profile (e.g., axial side profile 198, FIG. 6F) is devoid of angles, and connects the upper edge (e.g., upper edge 190) with the lower edge (e.g., lower edge 191) at a first azimuthal angle about the centroid. A second side profile is defined in step 220.
The second side profile (e.g., lateral side profile 199, FIG. 6G) is devoid of angles, and connects the upper edge with the lower edge at a second azimuthal angle about the centroid. Side profiles from the first side profile to the second side profile are interpolated in step 225. The surface profile (e.g., shape of interior baffle surface 192) is formed by interpolating side profiles from the first side profile to the second side profile, along all azimuthal angles between the first azimuthal angle and the second azimuthal angle. Because the plan view shape of the upper edge, the plan view shape of the lower edge, the first side profile and the second profile are devoid of angles, the resulting baffle profile will also be devoid of angles, such that the baffle surface profile transitions smoothly from the first side profile at the first azimuthal angle to the second side profile at the second azimuthal angle.

[0057] When a baffle profile is generated according to method 200, and the lower edge is other than a scaled version of the upper edge, the baffle profile will be a compound azimuthal and vertical profile. That is, the curvature of the generated baffle profile will be a function of azimuthal angle, an example being a difference between the slopes of axial side profile 198, FIG.
6F and lateral side profile 199, FIG. 6G.

[0058] In certain embodiments herein, light engines 110 and baffles 121, 122, provide additional aesthetic effects. For example, in certain embodiments, baffles may be highly reflective for highest illumination efficiency (like a lamp without a lampshade) while in other embodiments, baffles may be provided with a colored finish to provide visual interest (like a colored lampshade used with a lamp). Baffles may be of any color; however, relatively dark colors are preferable. This is because lighter colors may scatter too much light from the nearby light engine 110 to view comfortably, and/or because the viewer's eye, adjusting to the brightness of the light fixture, may perceive the color as a very light, "washed out" color. Light engines 110 may emit light of a color and/or white light of a chosen color temperature; color and/or color temperature may be selected as complementary to a color of the baffle. One of ordinary skill in the art will readily conceive many equivalents, extensions, and alternatives.

[0059] Another aesthetic effect is that of providing a clean "flash" across the light fixture as a viewer changes angle (e.g., as the viewer approaches from a distance and walks underneath the fixture). By providing a baffle profile that is continuously and downwardly concave in axial and lateral profiles, embodiments herein provide a baffle interior surface profile that provides continuity of such reflections. That is, a first reflection seen by a distant viewer coming into view of a light engine will be adjacent to the light engine. As the viewer approaches nadir relative to the light engine, the reflection will move from nearby the light engine toward an outer edge of the baffle interior surface.

[0060] Embodiments herein can be extensively customized through selection and integration of appropriate light engines, baffles, optics, and other accessories. For example, FIG.
8 shows in isometric view, and FIG. 9 shows in an exploded view, a light fixture 303 that integrates a variety of such optional accessories. Like light fixture 103 (FIGS. 1, 2B, 3A-3C), light fixture 303 includes housing 143, trim ring 133, adapter plates (hidden by housing 143 in FIGS. 8 and 9, see FIGS. 3B, 3C, 4A, 4B), spring clips 145, and baffle 123.
Light fixture 103 also includes three light engine positions 111, however the features described below are applicable to a fixture having any number of light engine positions. For ease of discussion, the three light engine positions are labeled 111-A, 111-B, and 111-C. It should be understand that embodiments of the present invention may include any type of light engines.
Those illustrated and described herein are intended to be exemplary only.

[0061] Light engines 110-1 in positions 111-A and 111-C include a heat sink 360 onto which is attached a light source housing 365. Light sources (such as, but not limited to LEDs, and obscured by light source housing 365 in the view of FIG. 9) are positioned within light source housing 365. For example, the light sources may be disposed on a circuit board at an upper surface of light source housing 365. Light source housing 365 engages a rotation/tilt housing 370 in a way that permits the light source housing 365 (with associated heat sink 360) to be tilted as desired. Rotation/tilt housing 370 engages an adapter plate 150-1 (obscured in the view of FIGS. 8 and 9, see FIG. 3C) through a ring that allows housing 370 to rotate with respect to adapter plate 150-1. Thus, in some embodiments, the rotation/tilt housing 370 is snap-fitted onto adapter plate 150-1, adapter plate 150-1 is snap-fitted onto housing 143, and baffle 123 is snap-fitted onto housing 143 below adapter plate 150-1. Other attachment means for any of these features, such as but not limited to interference fits and coupling with additional fasteners, are contemplated herein.

[0062] In the light engine 110-1 positioned in position 111-A, a primary optic 335 is received in the light source housing 365 and retained there by a retainer ring 321. Other optical accessories may also be provided within the light source housing 365 and retained thereon by the retainer ring 321. For example, in the illustrated embodiment, a honeycomb insert 325 and a glare shield 320 are positioned below the primary optic 335. In some embodiments, the retainer ring 321 can secure other optical accessories to the light source housing 365.
In some of these embodiments, an axial dimension of retainer ring 321 is modified so that the retainer ring 321 can span the required components.

[0063] FIGS 10A and 10B illustrate one such embodiment of a retainer ring 321.
Retainer ring 321, illustrated in isometric views in FIGS. 10A and 10B, includes a main body section 322 that defines a cylindrical axis 305. In the embodiment shown, a diameter of main body section 322 is larger than a length of main body section 322 along cylindrical axis 305, but other embodiments of retainer ring 321 that span larger components may have a main body section 322 having a length larger than its diameter. An inner retaining flange 324 extends radially inward from a distal end 326 of retainer ring 321; when installed on a light source housing 365, retaining flange 324 supports the desired components (e.g., primary optic 335, glare shield 320, honeycomb insert 325) on the light source housing 365. One or more coupling flanges 328 extend axially from a corresponding plurality of positions on a proximal end 327 of the main body section 322, with each of coupling flanges 328 forming one or more coupling features 329 that extend radially inward. Coupling features 329 engage with corresponding features of light source housing 365. Advantageously, coupling features 329 and the corresponding features of light source housing 365 are configured as ribs so as to snap-fit retainer ring 321 together with light source housing 365 without the use of tools. There are two coupling flanges 328 in the illustrated embodiment, but other embodiments could have more, fewer, or no coupling flanges (that is, coupling features 329 may be integrated directly with main body section 322).
100641 The light engine 110-1 positioned in position 111-C also includes a primary optic 335 received in the light source housing 365. However, in position 111-C, primary optic 335 is retained by a kicker reflector ring 330 (shown in greater detail in FIGS. 11A, 11B, and 11C).
Kicker reflector ring 330 is an example of an optical element (in this case, a reflector) integrated with a retainer ring that provides a similar functionality as retainer ring 321, but adds optical functionality. For example, kicker reflector ring 330 includes a main body section 342 along a cylindrical axis 305, analogous to main body section 322 of retainer ring 321.
Main body section 342 of kicker reflector ring 330 may be made with any length along cylindrical axis 305 needed to retain any intended components. A reflector surface 350 extends downwardly from a portion of main body section 342. An inner retaining flange 344 extends radially inward from a distal end 346 of kicker reflector ring 330. When installed on a light engine (e.g., light engine 110-1), retaining flange 344 couples components such as primary optic 335 with the light engine. One or more coupling flanges 348 extend axially from a corresponding plurality of positions on a proximal end 347 of the main body section 342, with each of coupling flanges 348 forming one or more coupling features 349 that extend radially inward from a proximal end 347 of each coupling flange 348. Coupling features 349 engage with corresponding features on the light source housing 365. There are two coupling flanges 348 in the illustrated embodiment, but other embodiments could have more, fewer, or no coupling flanges. Because of its direct integration with main body section 342, reflector surface 350 is advantageously in close proximity to primary optic 335 such that a significant optical effect - in this case, reflection of a large amount of light output from primary optic 335 toward a preferred direction - can be achieved with a small component. The direct integration of reflector surface 350 with main body section 342 also further facilitates user customization of light fixture 303 by being accessible to the user after installation, as discussed below.
[0065] Other optical components (such as but not limited to refractive optics, diffusers, and the like) can similarly be integrated into the light engine with retainer rings. Such components may be integrally formed with the retainer ring (e.g., by molding the component and the retainer ring as one piece) or coupled with the retainer ring as discussed above. Portions of the components so integrated may be selectively treated to provide desired optical characteristics, for example by metalizing reflector portions, painting or abrading diffusing surfaces, polishing specular optical surfaces and the like. Upon reading and comprehending the present disclosure, one of ordinary skill in the art will readily conceive many equivalents, extensions, and alternatives.
[0066] A pendant luminaire 310 is provided in light engine position 111-B. It is supported by an adapter plate 150-2 that, in turn, engages housing 143 to support pendant luminaire 310 from fixture 303. Electrical power for luminaire 310 may be provided by a cable that passes through center support 311.
[0067] Advantageously, some embodiments of light fixtures herein are designed so as to be installed and/or reconfigured from below a ceiling, or outside a wall or other inaccessible space. In these embodiments, all that is needed at the installation site is an electrical power source provided by a cable or other suitable connector, behind the surface where the fixture is to be installed. An installer can cut a hole (e.g., aperture 23 in mounting surface 7, FIG. 3A) that is sized and shaped for a housing (e.g., housing 141, 142, 143) of the light fixture. A driver box can be connected to the electrical power source; a power lead from the light fixture can connect with the driver box. The driver box can be pushed into the hole behind the mounting surface.
The light fixture can be configured with the desired light engines and accessories. The housing can be inserted into the hole and can couple with the mounting surface (e.g., using spring clips 145). A trim ring (e.g., trim ring 131, 132, 133) can be fitted with the housing to obscure the cut edge of the hole around the housing and provide a clean, finished appearance.

[0068] Some of these, and other embodiments, of light fixtures herein are also designed such that the fixtures are re-configurable in the field, with or without removal from the mounting surface. For example, if accessory substitution or a preferred direction of light reflection from a component integrated with a retainer ring is desired, the retainer ring can be turned, or removed to add, remove or substitute a component. Optionally, the trim ring may be removed for more convenient access and replaced after the adjustment or substitution. If a different light engine is desired in an installed fixture, the trim ring and baffle may be removed, the housing may be disengaged from the mounting surface, and the light engine may be disconnected from the driver box. An adapter plate (with the associated light engine) may be removed and replaced with the desired light engine/adapter plate combination. The new light engine may be connected with the driver box, the baffle may then be returned to the fixture, the housing may be returned to its original position in the mounting surface and the trim ring replaced.
[0069] Similarly, some embodiments of the fixture also provide for field interchangeable optics. For example, if a different spatial distribution of light is desired, a retainer ring 321, integrated kicker reflector 330 and/or other retainer ring embodiment may be removed from a light engine, the existing optic (e.g., primary optic 335) may be removed, replaced or substituted with a different primary optic or optical accessories designed to provide the desired spatial distribution. The retainer ring 321, integrated kicker reflector 330 or other retainer ring embodiment may then be replaced to couple the primary optic and/or other optical accessories with the light engine.
[0070] FIG. 12 is a schematic, isometric view illustrating relationships of manifold housing 143 with a plurality of adapter plates 150. Specifically, two adapter plates 150 illustrated in FIG. 9 are adapter plates 150-1 (see FIGS. 3B, 3C, 4A, 4B) and one is adapter plate 150-2 (see FIGS. 8, 9); the adapter plates are arranged about light engine positions 111-A, 111-B
and 111-C as they would be in FIG. 8, although adapter plates 150-1 are hidden in the perspective of FIG. 8. Adapter plates 150-1 are configured to mate with light engines 110-1, while adapter plate 150-2 is configured to support center support 311 of pendant 310 (FIGS. 8, 9). FIG. 12 provides axes denoting the vertical (Z), axial (A) and lateral (L) directions as used elsewhere herein; because the view of FIG. 12 is tilted forwardly about the axial axis, the L and Z directions are both vertical in the orientation of the drawing.

[0071] Housing 143 includes sidewalls 146 that define a manifold aperture 147, in which baffle 123 can be installed (see, e.g., FIGS. 3A, 3C, 8 and 9) and which continues through each light engine position 111-A, 111-B, 111-C. That is, manifold aperture 147 may be referred to as singular herein although housing 143 includes optional structural crossbars 149 for improved mechanical stability, subdividing manifold aperture 147 at an upper extent of housing 143. In embodiments, structural crossbars 149 are not present such that manifold aperture 147 continues unbroken from underside 106 to an upper side of housing 143. Thus, similarly to the term "manifold housing," the term "manifold aperture" herein is also not intended to mean only such housings that define or encompass only one light engine position; furthermore the use of "manifold aperture" in the singular should be taken to refer to all branches or subdivisions of such aperture. Sidewalls 146 extend from one or more upper edges of the manifold aperture to a lower edge of the manifold aperture. Dimensions of manifold aperture 147 define the axial and lateral directions; typically a longer dimension of manifold aperture 147 defines the axial direction while a shorter dimension of manifold aperture 147 defines the lateral direction, although this is not a requirement. Manifold housing 143 forms coupling features 148 that are complementary to coupling features 144 of adapter plates 150, as shown (some coupling features 144 are hidden in the view of FIG. 12).
[0072] In embodiments, adapter plates are complementary to light engines and/or other features mounted on the respective adapter plates, but may be configured with coupling features 144 of a similar type and spacing so as to couple with manifold housing 143, interchangeably with one another. Adapter plate 150-1 includes a ring feature 154 configured to couple with a lower edge of a tilt/swivel housing 370 (see FIGS. 8, 9). Ring feature 154 and tilt/swivel housing 370 are coupled in such a way that rotation of tilt/swivel housing 370 is not constrained, that is, tilt/swivel housing 370 can be adjusted to any angle about ring feature 154. Adapter plate 150-1 also defines an adapter plate aperture 158 through which a light engine may emit light.
[0073] Adapter plate 150-2 includes stiffeners 156 and a center hole 159 to accommodate center support 311 of pendant 310. Adapter plate 150-2 also includes strain relief features 157 such that wiring from a driver box can be anchored or tied off to adapter plate 150-2 and pass without tension into center support 311.

[0074] Although some embodiments are illustrated herein as linear fixtures (e.g., with all light engines of a given fixture arranged in a line), they need not be. For example, housings may be configured in other shapes such as arrays, s-shapes or other nonlinear arrangements of light engines. Upon reading and comprehending the present disclosure, one of ordinary skill in the art will readily conceive many equivalents, extensions, and alternatives.
[0075] Appendix A describes further non-limiting examples of embodiments of quiet-ceiling light fixtures.
[0076] The foregoing is provided for purposes of illustrating, explaining, and describing embodiments of the present invention. Further modifications and adaptations to these embodiments will be apparent to those skilled in the art and may be made without departing from the scope or spirit of the invention. Different arrangements of the components depicted in the drawings or described above, as well as components and steps not shown or described, are possible. Similarly, some features and subcombinations are useful and may be employed without reference to other features and sub combinations. Embodiments of the invention have been described for illustrative and not restrictive purposes, and alternative embodiments will become apparent to readers of this patent. Accordingly, the present invention is not limited to the embodiments described above or depicted in the drawings, and various embodiments and modifications can be made without departing from the scope of the claims below.

Claims (32)

WHAT IS CLAIMED IS:

1. A light fixture, comprising:
a manifold housing having sidewalls that define a manifold aperture, the sidewalls extending from one or more upper edges of the manifold aperture to a lower edge of the manifold aperture, wherein:
a first dimension of the manifold aperture defines an axial direction and a second dimension of the manifold aperture defines a lateral direction, and the manifold housing comprises first coupling features;
at least one adapter plate, comprising second coupling features, wherein:
the second coupling features of the at least one adapter plate removably couple with the first coupling features of the manifold housing to secure the at least one adapter plate to the manifold housing, and the at least one adapter plate defines an adapter plate aperture;
at least one light engine that emits light and that removably couples with the at least one adapter plate such that light emitted by the at least one light engine passes through the adapter plate aperture; and a baffle that substantially spans the manifold aperture and comprises at least one baffle cell;
wherein the at least one baffle cell comprises:
(i) an upper baffle edge that defines an upper baffle aperture through which light emitted by the at least one light engine passes, (ii) a lower baffle edge that defines an output aperture for the emitted light, and (iii) a baffle cell wall that extends from the upper baffle edge to the lower baffle edge.

2. The light fixture of claim 1, further comprising:
a trim ring that removably couples with the manifold housing so as to be positioned proximate the lower edge of the manifold aperture, wherein the trim ring is configured to extend outwardly from the manifold housing over an architectural surface.

3. The light fixture of claim 2, wherein the trim ring blocks light at angles higher than about 55 degrees from nadir in the lateral direction.

4. The light fixture of claim 1, wherein:
the at least one adapter plate comprises a first and a second adapter plate;
the at least one light engine comprises a first and a second light engine, wherein the first light engine removably couples with the first adapter plate and the second light engine removably couples with the second adapter plate; and the at least one baffle cell comprises a first and a second baffle cell;
wherein light emitted by the first light engine is reflected by the baffle cell wall of the first baffle cell and light emitted by the second light engine is reflected by the baffle cell wall of the second baffle cell.

5. The light fixture of claim 4, wherein the lower edges of the first and second baffle cells meet so as to form a divider that extends in the lateral direction between the first and second baffle cells.

6. The light fixture of claim 5, wherein the divider blocks light emitted by the first and second light engines at angles higher than about 55 degrees from nadir in the axial direction.

7. The light fixture of claim 1, wherein the at least one light engine comprises:
a light source housing;
a light source coupled with the light source housing; and a rotation/tilt housing that couples with the at least one adapter plate, and supports the light source housing such that the light source housing can tilt or rotate relative to the at least one adapter plate.

8. The light fixture of claim 1, wherein the at least one light engine comprises:
a light source housing;
a light source coupled with the light source housing;

a primary optic at least partially positioned within the light source housing;
and a retainer ring positioned on the light source housing to retain the primary optic within the light source housing.

9. The light fixture of claim 8, wherein the retainer ring comprises:
a retainer ring body;
coupling features engage the light source housing; and a secondary optic, formed integrally with the retainer ring body, that extends away from the light source housing.

10. The light fixture of claim 9, wherein the secondary optic comprises a reflector.

11. The light fixture of claim 10, wherein the reflector is a wall wash kicker reflector, and the retainer ring body is rotatably adjustable to adjust a direction in which light from the at least one light engine is reflected.

12. The light fixture of claim 1, wherein:
a plan view shape of the upper baffle edge forms a closed shape that is devoid of angles;
a plan view shape of the lower baffle edge forms a closed shape that is devoid of angles; and the baffle cell wall comprises an inner surface that is continuously, downwardly concave from the upper baffle edge to the lower baffle edge, and is devoid of angles.

13. A baffle for use in a light fixture that includes one or more light emitter positions, the baffle comprising:
one or more upper edges, each of the one or more upper edges encircling a respective light emitting aperture for a corresponding one of the light emitter positions, wherein:
each point of the one or more upper edges lies within an upper region, and plan view shapes of each of the one or more upper edges form closed shapes that are devoid of angles;

one or more lower edges corresponding in number with the one or more upper edges, each of the one or more lower edges encircling a respective output aperture for the corresponding one of the light emitter positions, wherein:
each point of the one or more lower edges lies within a lower region, and plan view shapes of each of the one or more lower edges form closed shapes that are devoid of angles; and an interior baffle surface that extends downwardly from each of the upper edges to corresponding ones of the lower edges, wherein:
the interior baffle surface is continuously, downwardly concave from each of the upper edges to each of the lower edges, and the interior baffle surface is devoid of angles.

14. The baffle of claim 13, wherein the plan view shape of each of the upper edges is circular.

15. The baffle of claim 13, wherein the plan view shape of each of the lower edges is substantially rectangular but includes rounded corners so as to be devoid of angles.

16. The baffle of claim 15, wherein each of the lower edges forms a shorter side and a longer side, and adjacent ones of the light emitter positions abut one another along the shorter sides.

17. The baffle of claim 13, wherein the upper region is a first plane, and the lower region is a second plane that is parallel with the first plane.

18. A retainer ring for a light fixture, comprising:
a cylindrical main body section that defines a cylindrical axis;
an inner retaining flange that extends radially inward from a distal end of the main body section, the inner retaining flange extending substantially about a circumference of the distal end;
wherein a proximal end of the main body section includes one or more coupling features that extend radially inward from the proximal end.

19. The retainer ring of claim 18, wherein the proximal end forms a plurality of coupling flanges that:
extend axially from a plurality of locations on the main body section, and include the coupling features.

20. The retainer ring of claim 18, wherein the retainer ring is formed of a molded plastic, and further comprising one or more optical features of the same molded plastic, that extend from at least one side of the retainer ring and are integrally molded with the cylindrical main body section.

21. The retainer ring of claim 18, wherein a diameter of the main body section is larger than a length of the main body section along the cylindrical axis.

22. A method of field reconfiguring a light fixture that is mounted within an aperture of a surface, comprising:
disengaging from the surface at least one spring clip that retains a housing of the light fixture within the aperture;
removing the housing from the aperture;
decoupling a first light engine from the housing;
electrically decoupling the first light engine from a driver electronics box;
electrically coupling a second light engine with the driver electronics box;
coupling the second light engine with the housing;
replacing the housing into the aperture; and re-engaging the at least one spring clip with the surface to retain the housing within the aperture.

23. The method of claim 22, further comprising:
decoupling a trim ring of the light fixture from the housing before disengaging the spring clip from the surface; and; and recoupling the trim ring with the housing after re-engaging the spring clip with the surface.

24. The method of claim 22, wherein:
the driver electronics box includes a plurality of driver circuits to support a respective plurality of light engine types; and electrically coupling the second light engine with the driver electronics box comprises electrically coupling the second light engine with a different driver circuit of the driver electronics box, than the first light engine.

25. The method of claim 22, further comprising:
decoupling an adapter plate for the first light engine from the housing, and recoupling a different adapter plate with the housing for the second light engine.

26. The method of claim 22, further comprising:
decoupling a first baffle from the housing, and recoupling a second baffle with the housing.

27. A method of generating a surface profile for a light fixture baffle, the method comprising:
defining an upper edge for the baffle, wherein a plan view shape of the upper edge is a first closed shape that lies within a first region and is devoid of angles, the closed shape defining a centroid;
defining a lower edge for the baffle, wherein a plan view shape of the lower edge is a second closed shape that is devoid of angles, and lies within a second region;
defining a first side profile that is devoid of angles, and connects the upper edge with the lower edge at a first azimuthal angle about the centroid;
defining a second side profile that that is devoid of angles, and connects the upper edge with the lower edge at a second azimuthal angle offset from the first azimuthal angle; and interpolating side profiles from the first side profile to the second side profile, along all azimuthal angles between the first azimuthal angle and the second azimuthal angle, so as to form the baffle surface profile, such that the baffle surface profile transitions smoothly from the first side profile at the first azimuthal angle to the second side profile at the second azimuthal angle.

28. The method of generating a surface profile for a light fixture baffle of claim 27, wherein the first region is an upper plane and the second region is a lower plane that is parallel with the upper plane.

29. The method of generating a surface profile for a light fixture baffle of claim 27, wherein interpolating each of the first and second side profiles comprises maintaining continuity of the baffle surface profile with both of the upper edge and the lower edge at all azimuthal angles between the first azimuthal angle and the second azimuthal angle.

30. The method of generating a surface profile for a light fixture baffle of claim 27, wherein the plan view shape of the upper edge is circular and the plan view shape of the lower edge is substantially rectangular, with rounded corners so as to be devoid of angles.

31. The method of generating a surface profile for a light fixture baffle of claim 27, wherein:
the first and second azimuthal angles are offset by ninety degrees from one another; and each of the upper and lower edges is bilaterally symmetric about each of the first azimuthal angle and the second azimuthal angle; such that the baffle surface profile is a first quadrant baffle surface profile; and further comprising generating corresponding second, third and fourth quadrant baffle surface profiles by generating mirrored versions of the first quadrant baffle surface profile, to form a composite baffle surface profile about a three hundred sixty degree azimuthal angle range.

32. The method of generating a surface profile for a light fixture baffle of claim 27, wherein a vertical spacing between the first region and the second region is sufficient to block a line of sight from beneath the baffle to any point within the first closed shape, at any position that is further from the first plane than the second plane and lies at an angle greater than 55 degrees away from a line extending vertically from the centroid.