Lighting system with combined directly viewable luminous or transmissive surface and controlled area illumination

• US 8,256,921 B2
• Filed: 05/15/2009
• Issued: 09/04/2012
• Est. Priority Date: 05/16/2008
• Status: Active Grant

• Current Assignee: Musco Corporation
• Original Assignee: Musco Corporation
• Inventors: Crookham, Joe P., Stone, Thomas A., Berns, James J.
• Primary Examiner(s): Husar, Stephen F
• Application Number:
  US12/466,640
• Publication Number:
  US 20090284966A1
• Time in Patent Office: 1,208 Days
• Field of Search: 362/33, 362/235, 362/242, 362/249.02, 362/249.03, 362/249.06, 362/248, 362/249.07, 362/431
• US Class Current: 362/242
• CPC Class Codes: F21S 8/033 the surface being a wall or like vertical structure, e.g. building facade
• CPC Class Codes: F21S 8/036 by means of a rigid support, e.g. bracket or arm
• CPC Class Codes: F21S 8/088 with lighting device mounted on top of the standard, e.g. for pedestrian zones
• CPC Class Codes: F21V 3/02 characterised by the shape
• CPC Class Codes: F21V 7/0016 on lighting devices that also provide for direct lighting, e.g. by means of independent light sources, by splitting of the light beam, by switching between both lighting modes
• CPC Class Codes: F21W 2131/10 Outdoor lighting
• CPC Class Codes: F21W 2131/103 of streets or roads
• CPC Class Codes: F21Y 2113/00 Combination of light sources
• CPC Class Codes: F21Y 2113/20 of different form
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]

Abstract

An apparatus, system and method for lighting an area, for example, an outdoors pedestrian area or building facade or an auto traffic area, or an indoor large area, which provides indicator/guide light, reference light for structures, and task lighting for a target area. The method uses first lighting sources that are directly viewable by observers and which can be historical, architectural, or aesthetically selected sources, but which produce a relatively low level of light or luminance insufficient to effectively light the area but sufficient to act as an indicator or guide, as well as to provide reference illumination on buildings or structures. Second lighting sources are configured to produce directional light to light the area but hide the light sources from most conventional observer viewing angles and may be enclosed within the general outlines of the globe or transmissive surface area of the fixture. Additionally, the fixture may appear to the average observer that the two sources are one historic or architectural source. Use of low-level directly viewable sources allows lower levels of light from the second sources to effectively light the area. This produces benefits regarding light pollution, such as reducing sky glow, glare, and spill light, as well as reducing energy usage.

Claims

1. A lighting system comprising:

a. a supporting structure or fixture adapted for placement at a lighting location;

b. a first light source creating a visible but relatively low level of luminance; and

c. a second light source or sources and an optic system or systems adapted to provide directed task light at or around the lighting location;

d. so that the luminance related to the first light source provides a perceived but relatively low level to observers, and luminance related to the second light source(s) provides directed and relatively low level of illumination on a target area, together presenting a traditional-looking light source but allowing much less light to be used for effective illumination of the target area while deterring glare, up-light and spill light.

2. The lighting system of claim 1 wherein the first light source comprises a translucent, prismatic, or diffusing member associated with a globe of spherical, acorn, or other shape or a flat pane or panel in a lantern-type fixture.

3. The lighting system of claim 1 wherein the source for at least one of the first and second light sources comprises a relatively low power light source.

4. The lighting system of claim 3 wherein the first light source comprises less wattage than the second light source, but both comprise substantially less wattage than a conventional light source such as incandescent or HID lighting.

5. The lighting system of claim 1 wherein at least one of the first and second light sources could comprise a solid-state light source such as an LED.

6. The lighting system of claim 1 wherein the second light source and optic system provide essentially no light above approximately 60 degrees from nadir to provide a light pattern which comprises a smaller angle from nadir than a full cut off (90 degree from nadir) light pattern.

7. The lighting system of claim 2 wherein the second light source and optic system are contained or mostly contained within volume of space at or near the globe.

8. The lighting system of claim 7 wherein the second light source and optic system provide substantially directional light.

9. The lighting system of claim 7 wherein the second light source and optic system shield direct view of the second light source from substantially all typical observer positions other than looking up from near or directly underneath the second light source.

10. The lighting system of claim 7 wherein the second light source has an equal or lesser emittance angle relative to horizontal as compared to a typical angle of viewing above horizontal.

11. The lighting system of claim 1 wherein the supporting structure comprises a frame or bracket adapted to mount to a post, pole, wall, or other elevating structure.

12. The lighting system of claim 1 wherein the relatively low level of luminance related to the first light source is created by transmission of light from the first light through a low intensity frosted bulb, filament, glowing panel or tube, or other non-point light source.

13. The lighting system of claim 1 wherein the relatively low level of luminance related to the first light source is created by reflecting light from the light source of a nearby surface such a portion of the fixture or a building wall surface.

14. The lighting system of claim 1 wherein reference luminance comprises light reflected by a surface of the fixture or a nearby surface.

17. The method of claim 1 wherein the relatively low level, multidirectional reference luminance, which is intended to be viewed, comprises a historically, architecturally, or aesthetically significant light fixture.

15. A method of lighting an outdoors area comprising:

a. generating a relatively low level, multi-directional reference luminance directly viewable by observers at and around the area;

b. illuminating one or more specific targets at the area with directional lighting comprising a full cutoff optic system that is shielded from direct view by most observers in defined viewing areas;

c. wherein the reference luminance is an effective amount to condition observers'"'"' eyes to a low level of luminance and produce the appearance that it is causing illumination of the area, but is small enough that it does not contribute significantly to sky glow, glare, or spill light;

nor to relative bright adaptation of the viewing eye when compared to the luminance from the area intended to be observed provided by the illumination from the directional lighting; and

the luminance from the target area provided by the directional lighting is an effective amount to provide observers with visual recognition of the targets, but low enough and directional enough that it does not contribute significantly to sky glow, glare, or spill light.

16. The method of claim 15 wherein the reference luminance comprises illumination of at least one of a translucent, prismatic, or diffusing member by a relatively low power light source.

18. The method of claim 15 further wherein the illumination providing the reference luminance and illumination providing the target luminance consume less energy because the reference luminance is sufficiently low that the adaptation level of the observers'"'"' eyes allows a reduced light level to effectively light the target area.

19. The method of claim 15 wherein at least one of the reference luminance and the target illumination is created by light from a solid state light source for improved lumen maintenance and light source life than other sources.

20. The method of claim 15 wherein the effective amount of reference luminance and target illumination is selected based on one or more of:

a. overall desired light level;

b. acceptable amount of glare; and

c. aiming angle of the illumination.

21. The method of claim 15 wherein the reference luminance and target luminance are of similar intensity levels.

22. The method of claim 15 wherein the reference luminance is generated from a light source of a relatively low power which is below the normal intensity threshold for eye adaptation relative to the luminance from the target area of this claim, and the luminance from the target area is generated by one or more light sources of relatively low power.

23. The method of claim 15 wherein the luminance is generated in a physical location above the lighting sources producing the illumination on the target area.

24. The method of claim 15 wherein reference luminance and target area illumination lighting sources are derived from a single light source.

25. The lighting system of claim 15 wherein the reference luminance comprises illumination a non-point light source such as a low intensity frosted bulb, filament, glowing panel or tube, or other non-point light source.

26. A method of lighting an area comprising:

a. creating luminance which can be directly viewed by observers at and around the area;

said luminance comprising a reference level of light to condition the observers'"'"' eyes to a low level of light wherein the light source creating the luminance is relatively low power;

b. creating illumination of targets in the area with one or more light sources that are relatively low power in comparison with existing art and directive optic systems to block the light sources from direct view by the eyes of observers in defined areas of observation, but provide a designated amount of illumination to the targets that may be, but is not limited to being, relatively low in comparison to existing fixtures;

c. wherein the low power light source for creating luminance by way of a luminous surface/transmissive surface/visible lamp is selected to minimize or decrease energy usage, sky glow, glare, or spill light relative to conventional fixtures as well as to condition observers'"'"' eyes, and the low power light source and directive optic system for illumination of targets is selected to minimize energy usage, sky glow, glare, or spill light.

27. The method of claim 26 wherein at least one of translucent, transparent, prismatic, or diffusing material comprises, a part of a lighting fixture, which simulates a historical, architectural, or aesthetic fixture, or is a part of a wall or other surface that is adjacent or nearby the lighting fixture.

28. The method of claim 26 wherein the luminance is created by illuminating a translucent, prismatic, or diffusing material.

29. The method of claim 26 wherein the non-point source luminance is created by a frosted bulb, filament, glowing panel or tube, or other non-point light source.

30. A method of providing aesthetic area lighting with less sky glow, glare and spill light comprising:

a. positioning a plurality of aesthetically-selected lighting fixtures at spaced-apart locations around the area to be lighted;

b. illuminating in each lighting fixture a directly viewable first light source with a relatively low power to provide a low level reference level of light for observers at or near the area;

c. illuminating predetermined targets within the area with light sources that are not directly viewable by the eyes of observers in defined areas of observation in or around the area;

d. so that

i. the lighting is aesthetically pleasing;

ii. the low reference level of light allows

1. a lower amount of light to adequately illuminate the targets;

2. less sky glow;

3. less glare; and

/or

4. less spill light.

31. The method of claim 30 wherein the first light source is created by illuminating a translucent, prismatic, or diffusing material.

32. The method of claim 30 wherein the first light source is created by a frosted bulb, filament, glowing panel or tube, or other non-point light source.

33. A method of lighting an area comprising:

a. placing a plurality of aesthetic, historical, or architectural fixtures around the area;

b. each fixture;

i. producing a relatively low, multi-directional reference luminance directly viewable by persons in and around the area and which does not produce human visual photo-responsive adaptation to persons in or around the area

ii. producing a relatively low, directional task lighting illumination which creates luminance from the target area, and which illumination is not directly viewable from most viewing angles by the persons in or around the area;

iii. so that

1. the fixtures provide both daytime or night-time visual guidance/demarcation of the area, and

2. the reference luminance provides ancillary illumination of the area at levels that accommodate dark sky regulations;

iv. the ratio of multi-directional luminance to luminance from the target area, perceived by most persons at or near the area deters triggering of visual photo-responsive adaptation response of the eyes of the persons such that the target area is obscured relative to the reference luminance.

34. A lighting fixture having the characteristics of the lighting of claim 33.

35. A method of lighting an area comprising:

a. providing directly viewable surface luminance;

b. providing directional, non-directly viewable task lighting illumination which produces viewable reflected task luminance;

c. the ratio between the highest luminance of the directly viewable luminance and the lowest luminance from the task illumination being within the adaptivity range of the human eye for the particular lighting application and environment, wherein the ratio as measured in lux is on the order of 20;

1 or 10;

1 for lower light or nighttime conditions and on the order of 6;

1 or 5;

1 for very low light conditions approaching lowest level of eye sensitivity.

36. The method of claim 35 further comprising selecting color temperatures of the light sources producing the directly viewable luminance and the reflected task luminance to be different.

37. A method of lighting comprising:

a. creating primary reference luminance and secondary luminance from a target area characterized by;

b. an effective scene brightness ratio between the secondary luminance and primary luminance which is less than the typical scene adaptive range of a human eye, wherein the ratio as measured in lux is on the order of 20;

1 or 10;

1 for lower light or nighttime conditions and on the order of 6;

1 or 5;

1 for very low light conditions approaching lowest level of eye sensitivity.

38. The method of claim 37 wherein the ratio is in the approximate range of 100:

1 to 1;

1.

39. The method of claim 38 wherein the ratio is on the order of 5:

1 or 6;

1.

40. The method of claim 37 wherein the color temperature differs between the primary light and the secondary light.

41. The method of claim 40 wherein the color temperature of the primary light is on the order of 3000K and the color temperature of the secondary light is on the order of 4000K.

42. A method for lighting in an area adapted for viewing or traversing by people comprising:

a. providing a non-point light source at or near the area;

b. providing task lighting generally at or near the non-point light source;

c. producing with the non-point light source and task lighting a scene brightness ratio that is less than the typical scene adaptive range of a human eye;

d. wherein the non-point is directly viewable from most viewing angles but a source of the task lighting is not.

43. The method of claim 42 wherein for a given scene adaptive range of the human eye, the scene brightness ratio is less than or equal to 10:

1.

44. The method of claim 42 wherein the non-point light and task lighting comprise different color temperatures.

45. The method of claim 42 wherein the non-point light is directly viewable by people, the task lighting produces luminance at the target area which is a luminance level to which a typical human eye adapts, and luminance from the directly viewable non-point light is at or below the luminance from the task lighting so that the eye receives maximum utilization of the task lighting of the targeted area.

46. The method of claim 45 further comprising the task lighting is produced by a light source and the light source of the task lighting is not in the normal field of vision of people.

47. The method of claim 42 wherein the non-point light functions its a visible reference or guide in daylight or at nighttime.

48. The method of claim 42 wherein the non-point light comprises a light source that is directly viewable from most viewing angles or comprises a wall or surface spaced from a light source.

49. The method of claim 42 further comprising utilizing one or more of the following parameters in providing the non-point light and task lighting:

light source lumens, desired level of luminance, ambient and background light levels, type and reflectivity of target area, desired target brightness relative to ambient light, mounting height or heights, and optical configurations.