Abstract:
A modular lighting system for lighting a work area is disclosed. The system includes a power supply with power outlets for powering LED fixtures. The power supply preferably operates at or below a fixed power output level, such as to illuminate the work area using less than 0.2 Watts per square foot of energy. The lighting system also includes an occupancy sensor and/or a light level sensor for controlling lighting levels in the work area in response to detection of a person, ambient light levels and/or a combination thereof. The lighting system can also include computer unit with a micro-processor and a memory unit for running software or firmware the executes lighting programs, stores light usage histories and/or provides system reports to a remote computer by a wireless means and/or over a computer network.

Description:
RELATED APPLICATIONS 
       [0001]    This application is a Continuation-in-Part application of the co-pending application Ser. No. 11/432,036, titled “WORKSPACE LIGHTING SYSTEM”, filed May 10, 2006, which claims priority under 35 U.S.C. 119 (e) of the co-pending U.S. Provisional Patent Application Ser. No. 60/680,890, filed May 12, 2005, and titled “PERSONAL LIGHTING SYSTEM.” This patent application also claims priority under 35 U.S.C. 119 (e) of the. co-pending U.S. Provisional Patent Application Ser. No. 60/859,674, filed Nov. 17, 2006, and titled “WORKSPACE LIGHTING.” The U.S. patent application Ser. No. 11/432,036, titled “WORKSPACE LIGHTING SYSTEM”, filed May 10, 2006, the U.S. Provisional Patent Application Ser. No. 60/680,890, filed May 12, 2005, and titled “PERSONAL LIGHTING SYSTEM”, and the co-pending U.S. Provisional Patent Application Ser. No. 60/859,674, filed Nov. 17, 2006, and titled “WORKSPACE LIGHTING”, are all hereby incorporated by reference 
     
    
     FIELD OF THE INVENTION 
       [0002]    This invention relates to the field of interior lighting. More particularly, this invention relates to a device for work area illumination comprising luminaires, power supply, and lighting controls. 
       BACKGROUND OF THE INVENTION 
       [0003]    Illumination is provided using many types of light sources and distribution methods. In interior office lighting, illumination is typically provided through a combination of overhead luminaires and task lighting. Existing best practices and governmental standards proscribe a fixed total amount of energy per unit area illuminated for these two lighting types. Overhead lighting is well understood. High-quality, suspended, direct-indirect lighting can meet or exceed these goals in virtually every situation. Task lighting is more complicated and usually not deeply discussed in guidelines or regulations. 
         [0004]    In addition, the demographics of American society indicate that the workforce is aging. The eye deteriorates with age and older workers may require as much as twice as much light to perform the same task as a younger worker. Appropriate task lighting can assist these workers and make them more productive, without lighting the entire space to an unnecessarily high level. 
         [0005]    Task lamps vary widely in shape, performance, cost, and efficiency leading to a bewildering array of options. Also, the portability of task lamps makes them prone to loss or theft. Lighting designers, architects, and engineers have traditionally been unwilling to depend on task lighting for illumination. Without a method of verifying appropriate task lighting, the overhead lighting must be over-designed to ensure proper light levels. 
         [0006]    Under-cabinet lights have also used as task lights to increase desk illumination. These lights are not suited for this application. A typical task, such as a single piece of paper, is fundamentally different in size and shape from a typical cabinet. Under-cabinet lights are either too large to efficiently illuminate a task, or too small to fully illuminate the under-cabinet wall. 
         [0007]    Beyond the difficulty of selecting and maintaining task lights, there are fundamental energy concerns. Fluorescent tubes or compact fluorescent bulbs have been the most efficient and cost effective technology for task lighting. These sources are only available in a fixed number of packages, and cannot be subdivided into smaller energy loads. The lowest level of the existing packages is relatively high and this leads to over-illumination of task, and potentially illuminance uniformity issues across the space. More simply, there are both lighting quality and energy efficiency drawings to having a single over-illuminated area in a work space. Mandating a single type of lamp for an entire office may lead to small workstations being over-lit and larger workstations have sections of brightness juxtaposed with darker areas. Due to these issues, task lighting has not gained broad acceptance in the building or lighting communities as a reliable tool for increasing light levels in an office space. 
         [0008]    Many alternate technologies exist to light workplaces. In particular, LED technology has improved greatly in the past years and has become viable as a solution for targeted applications in the field of general illumination. The existing LED products in the market are designed as direct replacements for existing products, such as task, accent, or under-cabinet lights. These solutions are typically unsatisfactory due to the high cost of LEDs relative to other light source. 
       SUMMARY OF THE INVENTION 
       [0009]    The present invention is directed to a lighting system for lighting cubicles or other work areas. The system includes a direct current (DC) power supply with a plurality of power outlets for powering a corresponding plurality of light fixtures (or luminaires). The light fixtures are equipped with plug features that detachably plug into one or more of the power outlets. The light fixtures are preferably need specific, such that each of the light fixtures provides a unique lighting function and/or photometric response. For example, the plurality of light fixtures can include light fixtures that provide task lighting, accent lighting, under-cabinet lighting and wall wash lighting. Preferably, the light fixtures have light emitting diode (LED) arrays and heat sinks to cool the LED arrays while the light fixtures are on. 
         [0010]    In accordance with the embodiments of the invention, the power supply is configured to have a selectable or fixed power output level, such that the total power that is provided by any one of the power outlets and/or the sum of the power outlets is maintained at or below the selected or the fixed power output level. The plug features of the light fixtures can be coded, shaped or otherwise matched to fit into or engage specific power outlets on the power supply. Alternatively, the plug features are universal plug features that can be plugged into any one of the power outlets on the power supply. In further embodiments of the invention the light fixtures and/or the plug features are coded and/or matched to fit into or engage specific power outlets on the power supply based on an intended use or photometric response of each specific light fixtures. The modular construction the lighting system described above allows the power supply or any one of the light fixtures to be exchanged or replaced with a new one when necessary without requiring that the entire lighting system be replaced. 
         [0011]    In accordance with further embodiments of the invention, a the lighting system, in addition to a manual switch, includes a sensor that is configured to turn on and off the lighting system. For example, the lighting system includes an ultrasonic or infrared occupancy sensor that turns on the lighting system in response to detection of a person in a vicinity of the lighting system and turns off the lighting system at a time after that presence of the person is no longer detected by the sensor. In accordance with still further embodiments of the invention, the lighting system includes a light level sensor and the system adjusts the power output level of the power supply based on the amount light measured. 
         [0012]    The lighting system of the present invention can also include a computer unit with a micro-processor and a memory unit for running software or firmware that execute lighting programs, stores lighting usage histories and/or provides system reports to a remote computer linked by a wireless means and/or over a computer network. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]      FIGS. 1A-C  illustrate simplified drawings of typical work spaces. 
           [0014]      FIGS. 1D-E  illustrate simplified drawings of prior art lighting fixture types. 
           [0015]      FIG. 2A  illustrates a detailed schematic of the preferred modular luminaire structure, in accordance with the instant invention. 
           [0016]      FIG. 2B  illustrates a detailed schematic of the preferred modular power supply structure, in accordance with the instant invention. 
           [0017]      FIG. 2C  illustrates a detailed schematic of the preferred modular controller structure, in accordance with the instant invention. 
           [0018]      FIG. 3A  illustrates a detailed drawing of a device for work area illumination comprising luminaires, power supply, and lighting controls, in accordance with the instant invention. 
           [0019]      FIG. 3B  illustrates a magnified, detail drawing of a power supply, in accordance with the instant invention. 
           [0020]      FIG. 3C  illustrates a magnified, detail drawing of a task luminaire, in accordance with the instant invention. 
           [0021]      FIG. 3D  illustrates a magnified, detail drawing of an accent luminaire, in accordance with the instant invention. 
           [0022]      FIG. 3E  illustrates a magnified, detail drawing of a wall wash luminaire, in accordance with the instant invention. 
           [0023]      FIG. 3F  illustrates a magnified, detail drawing of a controller, in accordance with the instant invention. 
           [0024]      FIG. 4A  illustrates a simplified functional drawing of a power supply, in accordance with the instant invention. 
           [0025]      FIG. 4B  illustrates a simplified functional drawing of task or accent luminaire, in accordance with the instant invention. 
           [0026]      FIG. 4C  illustrates a simplified functional drawing of a wall wash luminaire, in accordance with the instant invention. 
           [0027]      FIG. 4D  illustrates a simplified functional drawing of a controller, in accordance with the instant invention. 
           [0028]      FIG. 5A  illustrates a light distribution graph of the configured lighting provided by a task or accent luminaire, in accordance with the instant invention. 
           [0029]      FIG. 5B  illustrates a light distribution graph of the configured lighting provided by a wall wash luminaire, in accordance with the instant invention. 
           [0030]      FIG. 6A  illustrates a finned lamp head or luminaire head configuration, in accordance with the instant invention. 
           [0031]      FIG. 6B  illustrates a lamp or luminaire with finned lamp head or luminaire head configuration, in accordance with the instant invention. 
           [0032]      FIGS. 6C-F  show different geometries of finned lamp head or luminaire head configurations, in accordance with the instant invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0033]    The current invention is a device for work area illumination comprising luminaires, power supply, and lighting controls. Specifically, the current invention is a system of task luminaires and supporting components for the purpose of illumining a limited segment of a larger office area. In the current invention, lighting for both horizontal and vertical illumination of work areas is provided through a device for work surface illumination comprising luminaires, power supply, and lighting controls. The luminaires of the current invention emit light in a variety of distributions. Combinations of task-specific luminaires can be tailored to match the space, while maintaining a uniform interface and appearance. The current invention considers both the aesthetic and quantitative aspects required to generate even and pleasing workplace lighting. The aesthetic aspect ensures that all the luminaires in the space are of a similar appearance, pleasing shape, and are designed to minimize negative lighting effects, such as glare. The Illuminating Engineering Society (IES) of North America published guidelines for light levels for many tasks and activities based on the nature of the task, the size of the objects handled, the detail required, the average age of the people in that space, and other factors. The typical office is lit to an illumination of 20 to 70 “foot-candles.” This large range highlights the difference between the minimum lighting required for basic tasks and the higher levels needed in more visually intensive tasks or situations. Quantitatively, the current invention provides sufficient additional light to bring illumination levels from the lower range of office lighting to the upper range. 
         [0034]    A major advantage of the lighting provided by the current invention is that light levels are increased exactly where they are needed. Existing task lamps often provide much more than the IES recommended illumination, while simultaneously leaving other parts of the workspace without any additional lighting. The current invention uses a number of less powerful luminaires placed throughout the space to provide appropriate illumination at all desired locations. 
         [0035]    The current invention provides more effective and efficient lighting, especially when combined with an overhead lighting system that illuminates the space to a relatively low level. Luminaires with a traditional task distribution can be used for high levels of illumination when doing high-detail work. Lower-power versions of traditional task lights, as used in the current invention, can provide a similar function, but use as little as 35% of the energy a traditional task solution. These low power levels are practical for LEDs sources, but can not be achieved with traditional lighting sources such as incandescent or fluorescent. 
         [0036]    The current invention provides more effective lighting with increased system efficiency. Specifically, the current invention discloses a device for work surface illumination comprising a plurality of luminaires, a power supply, and a plurality of lighting controls. The device for work surface illumination disclosed achieves a series of objectives: increased illumination of horizontal surfaces; increased illumination of vertical surfaces; increased illumination of accent items; efficient distribution of light across a work area; ease of fabrication, shipping, installation, and repair; user adjustability and customization; various mounting configurations to meet a broad range of applications including, but not limited to, under cabinet, desktop, desk clamp, or furniture mounted; and long-life performance. 
         [0037]    In the current invention, a plurality of luminaires provides the possibility for a plurality of lighting distributions including, but not limited to, task, wall wash, accent, and spot. Further, the current invention comprises a means for providing lighting from a plurality of light sources with a plurality of lighting distributions. 
         [0038]    In other embodiments of the current invention, the device for work surface illumination comprises a plurality of luminaires with a plurality of lighting distributions. Each luminaire comprise a mounting structure and an optical element coupled to the mounting structure. In addition, the luminaire comprises a means for providing light coupled to the optical element. Further, the device comprises a power source coupled to the luminaires. Also, the device comprises a means for controlling the luminaires and power supply coupled to the power supply or luminaires. The means for controlling the luminaires and power supply uses a plurality of inputs including, but not limited to, input from the user, detection of an occupant, light level, temperature, computer interface, and/or time. 
         [0039]    Thus, the current invention provides more effective and efficient lighting for a workspace. Further, the current invention has the added benefits of lower total system cost, ease of assembly and shipping, providing increased light levels where needed, faster installation times, and reducing and making repair and maintenance easier. In sum, the current invention provides targeted illumination, accommodates a variety of uses, is glare free, and provides these benefits in spaces of varying configuration and layout where it is currently either impossible or not desirable to use of prior task lighting. 
         [0040]    Now referring to  FIGS. 1A-C  that illustrate simplified drawings of typical cubical and task lighting layouts in accordance with the present invention. Specifically,  FIG. 1A  illustrates a small 6′ by 8′ individual cubical  102 , illuminated by a task lamp  101 , with the desk area farthest from the task lamp  103  receiving no significant illumination from the task lamp.  FIG. 1B  illustrates a larger 8′ by 10′ cubical layout  111 , with a first binder bin  112  and a second binder bin  116 , illuminated by an under-cabinet luminaire  113 . The desk surface underneath under-cabinet luminaire  114  is lit to an excessively high level. The desk surface farthest from the under-cabinet luminaire  115  receives no significant illumination from under-cabinet lamp.  FIG. 1C  illustrates a group of linked cubicals  125 , such as in a call center. The group of linked cubicals is illuminated by a set of luminaires  121 ,  124 ,  126 ,  127 . The desk area across from the luminaire  121  ( 122 ) is an example of a poorly lit space. A binder bin  123  contributes to a lower light level on the desk area  122 . The energy used per luminaire in these examples is typically between 12 and 32 Watts. 
         [0041]      FIG. 1D-E  illustrate typical prior art luminaires. Specifically,  FIG. 1D  illustrates an under-cabinet luminaire. The under-cabinet luminaire is composed of a lamp  131 , reflector  132 , ballast  133  and housing  134 . The lamp  131  is typically a ‘T8’, a 1″ diameter fluorescent tube. The size of the lamp  131  typically requires the housing  134  to be at least 1″ tall. The ballast  133  converts alternating current from the wall (not shown) to the appropriate voltage to power the lamp  131 .  FIG. 1E  illustrates a task lamp. The task lamp. A base  141  supports the task lamp. The base  141  is connected to the lamp head  144  by an arm  142 . The lamp head supports a ballast  143 , reflective cavity  145 , and lamp  146 . The lamp  146  is typically a bent fluorescent tube using between 7 and 18 Watts of energy. 
         [0042]      FIG. 2A  illustrates a detailed schematic of the preferred modular luminaire structure, in accordance with the instant invention. Specifically, the luminaire comprises a housing  206  and a circuit board  205 . The circuit board  205  is attached to the housing  206  and is further attached to a means for current control  209  and a DC power jack  201 . The DC power jack  201  is electrically connected to the means for current control through a first electrical connection  212  and a second electrical connection  211 . The preferred embodiment of the system utilizes different form factors for the DC power jack  201  to indicate the amount of current used by the modular luminaire. 
         [0043]    The circuit board  205  is further connected to Light Emitting Diodes (LEDs)  202   a - f ,  203   a - f . In the preferred embodiment of the system, the LEDs are electrically connected in series to match the voltage drop across the Light Emitting Diodes  202   a - f ,  203   a - f  to the voltage applied to the DC power jack  201 . Each series of LEDs  202   a - f ,  203   a - f  is then further wired in parallel. The means for current control  209  is connected to a first string of LEDs  202   a - f  by a first means for electrical connection  208  and to a second string of LEDs  203   a - f  by a second means for electrical connection  210 . Both strings of LEDs  202   a - f ,  203   a - f  are further connected to the means for current control  209  by a third means for electrical connection  204 . This structure allows the use of simple current regulation strategies, such as linear regulation, in an efficient manner. The structure further ensures the LEDs  202   a - f ,  203   a - f  all experience very similar current flows to ensure similar operating characteristics. 
         [0044]    The luminaire further comprises a heat sink  207  that is mechanically attached to the circuit board  205  and provides cooling for the means for current control  209  and the LEDs  202   a - f ,  203   a - f . In the preferred embodiment, the heat sink  207  is integrated into a portion of the housing  206 . 
         [0045]      FIG. 2B  illustrates a detailed schematic of the preferred modular power supply structure, in accordance with the instant invention. Specifically, the power supply comprises a housing  229  and a circuit board  228 . The circuit board  228  is attached to the housing  229  and is further attached to: a means for connecting to AC power  232 , a means for voltage regulation  234 , a means for controlling the operation of the power supply  224 , a means for connecting to a sensor  227 , a means for indicating status  225 , and a plurality of DC power jacks  221   a - g . The power supply further comprises: a first means for electrical connection  222  and a second means for electrical connection  235  that electrically connect the means for voltage regulation  234  and the DC power jacks  221   a - g , a third means for electrical connection  233  and a fourth means for electrical connection  231  that electrically connect the means for voltage regulation  234  to the means for connecting to AC power  232 , a fifth means for electrical connection  223  that connects the means for voltage regulation  234  to the means for controlling the operation of the power supply  224 , a sixth means for electrical connection  230  that connects the means for controlling the operation of the power supply  224  to the means for connection to a sensor  227 , and a seventh means for electrical connection  226  that connects the means for controlling the operation of the power supply  224  to the means for indicating status  225 . 
         [0046]    In the preferred embodiment, the DC jacks  221   a - g  are of an identical size. The DC jacks  221   a - g  are further spaced evenly to allow an multi jack connector (not shown) to connect to any combination of a plurality of adjacent DC jacks  221   a - g . The DC jacks  221   a - g  are further chosen to be a different size from the DC power jack  201  contained in the modular luminaire. The DC jacks  221   a - g  and DC jack  201  are further chosen such that the total power from the power supply is evenly divided between DC jacks  221   a - g  to calculate the minimum luminaire power (not shown) and DC jack  201  is chosen to indicate multiples of the minimum luminaire power. The multi jack connector (not shown) is chosen to indicate the same multiple of the minimum luminaire power. Preferably, the total power from the power supply is chosen to be between 9 and 60 Watts. Also preferably, multiple power supplies are made available with different power ratings to accommodate different situations and make full use of the modular nature of the product. 
         [0047]    The control circuitry  224  is designed to take inputs from the means for connecting to a sensor  227  and control the means for voltage regulation  234  by turning the means for voltage regulation  234  on and off. In the preferred embodiment, 24 Volts is produced by the means for voltage regulation  234 . The control circuitry  224  is further designed to indicate the status of the system using the means for indicating status  225 . In the preferred embodiment, the means for indicating status  225  is a red LED mounted such that it is visible outside of the housing  229 . The means for indicating status  225  is turned on to indicate normal operation and is flashed to indicate abnormal conditions. 
         [0048]      FIG. 2C  illustrates a detailed schematic of the preferred modular controller structure, in accordance with the instant invention. Specifically, the controller comprises a housing  248  and a circuit board  247 . The controller further comprises: an input device  251 ; a connector  246 ; a sensing device  241 ; an indicator  245 ; and a means for controlling the controller  243 . The controller also comprises: a means for connecting the input device  251  to the means for controlling the controller  243 ; a means for connecting the sensing device  242  to the means for controlling the controller  243 ; a means for connecting the connector  246  to the means for controlling the controller  243 ; and a means for connecting the indicator  245  to the means for controlling the controller  243 . 
         [0049]    In the preferred embodiment, the input device  251  is a push button switch. The switch indicates the desire to turn the modular power supply off. The sensing device  241  is preferred to be an occupancy sensor, and is preferred to be calibrated to detect occupants in the range 0-8′ from the sensing device  241 . The connector  246  is preferred to be a RJ11 connector and transmit signals including, but not limited to, power, ground, occupancy status, and input device status. In other embodiments, the connector  246  is a RJ45 connector, and in further other embodiments the connector  246  is eliminated and replaced by a means for connecting the controller to the power supply (not shown). It is also preferred that the indicator  245  is a red LED that lights when the sensing device detects a signal, such as the preferred occupancy sensor detecting motion. 
         [0050]      FIG. 3A  illustrates a detailed drawing of a device for work area illumination comprising luminaires, power supply, and lighting controls, in accordance with the instant invention. Specifically, the device for work area illumination comprises a plurality of luminaires for task, accent, or wall illumination  301 , 309 , 310 ,  313 . The device further comprises a power supply  303  and a control device  306 . Additionally, the device comprises a system of interconnection cables  302 ,  304 ,  305 ,  312  that connect the power supply  303  to the luminaires  301 , 309 ,  310 ,  313 , and a means for connecting the power supply  303  to the control device  306 . The system further comprises a power cord  311  that connects the power supply  303  to AC current from a standard wall outlet (not shown). 
         [0051]    In the preferred embodiment, the luminaires  301 ,  309 ,  310 ,  313  are selected from the group consisting, but not limited to: 6-Watt task luminaire; 3-Watt accent luminaire; and 6-Watt wall wash luminaire. In the diagramed embodiment, one 6-Watt task luminaire, one 3-Watt accent luminaire, and two wall wash (under cabinet) luminaires are used to illuminate a space. In the preferred embodiment, users may select between a wide variety of luminaire types and power ranges. Additionally, users may select a power supply  304  with a power rating appropriate for their work space. In the preferred embodiment, the power supply  304  is selected to meet or exceed the government recommended limit of 0.2 Watts per square foot. 
         [0052]    To illustrate, in a small work environment as shown in  FIG. 1A , the user may select a 9-Watt power supply. The total area of the cubical shown in  FIG. 1A  is 48 square feet. A 9-Watt power supply yields a power density of 0.1875 Watts per square foot. Similarly, a larger work area can use a 25-Watt power supply to illuminate a 125 square foot cubical. A set of work areas in a call center can combine to use a 60-Watt power supply to light a 300 square foot area. These power supplies are preferred to remain at or below 60-Watts to maximize the benefits of LED lighting and provide control to a manageable group of luminaires. Limiting the power to a low level, especially when combined with a low-level ambient lighting scheme for the entire building, can result in dramatic energy savings while actually increasing user satisfaction due to increased user control. 
         [0053]      FIG. 3B  illustrates a magnified, detail drawing of a power supply, in accordance with the instant invention. Specifically, the power supply comprises a housing  332  containing circuitry (not shown), with an indicator light  333  and a plurality of connection jacks  329   a - g . The power supply further comprises a power cable  331  connecting the power supply to AC current, and an input cable  330  connecting the power supply to the input device (see  FIG. 3A ). 
         [0054]    Preferably, the connection jacks  329   a - g  are identical DC power jacks, evenly spaced. Connection cables  321 ,  323 ,  326 ,  328  are used to connect the power supply to the luminaires (shown in  FIG. 3A ). In the preferred embodiment, 3-Watt luminaires are connected using a single DC power jack, as shown by cable  328  meeting DC jack  329   a . 6-Watt luminaires are connected using two DC power jacks, as shown by connector  322  meeting DC jacks  329   f - g , connector  324  meeting DC jacks  329   d - e , and connector  327  meet DC jacks  329   b - c . In alternate embodiments, 9-Watt luminaires are connected using three DC power jacks. 
         [0055]    In further alternate embodiments the unit of division is changed and 2-Watt luminaires are connected using one jack, 4-Watt luminaires are connected using two jacks, and 6-Watt luminaires are connected using three jacks. Further, it is possible to connect a luminaire that is between any power ratings using the number of jacks appropriate to the higher power rating. 
         [0056]      FIG. 3C  illustrates a magnified, detail drawing of a task luminaire, in accordance with the instant invention. Specifically, the task luminaire comprises a base  341  and a connector  342 . The task luminaire further comprises a means for articulation  344 , an arm  345 , and second means for articulation  350 , a second arm  349 , a third means for articulation  348 , a lamp head  346 , and a heat sink  347 . 
         [0057]    In the preferred embodiment, a cable  343  from the power supply (see  FIG. 3A ) connects to the connector  342 . The connector is preferably a DC power jack, with the size of the DC power jack indicating the power of the lamp. In the preferred embodiment, 3-Watt luminaires utilize a 1.3 mm DC power jack, 6-Watt luminaires utilize a 1.7 mm DC power jack, and the power supply utilizes 2.5 mm DC power jacks. The task luminaire is preferably a 6-Watt luminaire. 
         [0058]    Preferably, the arm  345  and second arm  349  are of equal length and approximately 12″ long. In this embodiment, the means for articulation  344 , second means  350 , and third means  348  combine to allow the lamp head  346  to be positioned appropriately for general task use. Specifically, they allow the lamp head  346  to be raised and lowered while remaining parallel to the horizontal work surface (not shown), and to be rotated around a vertical axis (not shown). Additionally, the means  344 ,  350 ,  348  allow the lamp head  346  to tilt up and down. In alternate embodiments, the luminaire may have only a single arm and two means of articulation. 
         [0059]    In the preferred embodiment, the heat sink  347  is integrated into the lamp head  346 . The lamp head  346  is constructed of aluminum and the heat sink  347  consists of slots cut into the lamp head  346 . The heat sink  347  is preferred to be large enough to maintain the lamp head  347  at a temperature below 50 degrees C. It is further preferred for the temperature of the LED contained in the luminaire (see  FIG. 2A ) be maintained below 40 degrees C. Typically, this will lead to the total surface area of the heat sink  347  being approximately 10 square inches for each watt of power used in the lamp head  346 . This will ensure the rated lifetime of the LEDs is met and prevent premature failure of the LEDs and thus the luminaire. 
         [0060]      FIG. 3D  illustrates a magnified, detail drawing of an accent luminaire, in accordance with the instant invention. Specifically, the accent luminaire comprises: a base  361 ; a connector  362 ; a means for articulation  364 ; an arm  365 ; a second means for articulation  366 ; a second arm  367 ; a third means for articulation  368 ; a accent head  370 ; and a heat sink  369 . A cable  363  connects the luminaire to the power supply (see  FIG. 3A ). Preferably, the luminaire uses 3 Watts of power and the connector  362  is a DC power jack. 
         [0061]    Preferably, the arm  365  and second arm  367  are of equal length and approximately 8″ long. In this embodiment, the means for articulation  364 , second means  366 , and third means  368  combine to allow the accent head  370  to be positioned appropriately for accent use Specifically, they allow the accent head  370  to be raised and lowered while remaining parallel to the horizontal work surface (not shown), and to be rotated around a vertical axis (not shown). Additionally, the means  364 ,  366 ,  368  allow the accent head  370  to tilt up and down, and to rotate around the axis of the second arm  367  as shown in  FIG. 3D . This allows the accent luminaire to light both horizontal and vertical surfaces in a pleasing manner. In alternate embodiments, the luminaire may have only a single arm and two means of articulation. 
         [0062]    In the preferred embodiment, the heat sink  369  is integrated into the accent head  370 . The accent head  370  is constructed of aluminum and the heat sink  369  consists of slots cut into the lamp head  370 . The heat sink  369  is preferred to be large enough to maintain the accent head  370  at a temperature below 50 degrees C. It is further preferred for the temperature of the LED contained in the luminaire (see  FIG. 2A ) be maintained below 40 degrees C. Typically, this will lead to the total surface area of the heat sink  369  being approximately 10 square inches for each watt of power used in the accent head  370 . This will ensure the rated lifetime of the LEDs is met and prevent premature failure of the LEDs and thus the luminaire. 
         [0063]      FIG. 3E  illustrates a magnified, detail drawing of a wall wash luminaire, in accordance with the instant invention. Specifically, the wall wash luminaire comprises: a body  381 ; a connector  382 ; an endcap  384 ; a means for mounting  385 ; a second means for mounting  386 ; and a second endcap  387 . The endcap  384  and second endcap  387  are connected to the body  381 . 
         [0064]    The means for mounting  385  and second means for mounting  386  each consist of a hole through the body  381 . In alternate embodiments strips of adhesive-backed Velcro may be used to attach the luminaire to a cabinet or shelf (not shown). In further embodiments, magnets (not shown) may be mounted inside the body  381  to attach to a ferrous metal shelf, or to a ferrous plate attached to any surface. Screws may be used to attach the luminaire to the cabinet or shelf (not shown) through the holes. 
         [0065]    In the preferred embodiment, the cable  383  from the power supply (see  FIG. 3A ) connects to the connector  382 . The connector is preferably a DC power jack, with the size of the DC power jack indicating the power of the lamp. In the preferred embodiment, The task luminaire is preferably a 6-Watt luminaire. In alternate embodiments the task luminaire is a 9-Watt luminaire. In further other embodiments, both 6 and 9-Watt luminaires are available for purchase and can be combined through the modular nation of the power supply. In the preferred embodiment the body  381  is 42.5″ long and fits under a standard 4′ nominal binder bin (not shown). In alternate embodiments, the luminaire is available in 2′, 3′, and 4′ nominal lengths. These luminaires are each optimized to light different segments of wall space using a specific amount of power. The 4′ luminaire is preferred. 
         [0066]      FIG. 3F  illustrates a magnified, detail drawing of a controller, in accordance with the instant invention. The controller comprises a housing  391 , a sensor  392 , a means for input  393 , and a connector  394 . The housing is preferred to be gray or black and low profile. Typical outer dimension are 4.5″ by 2.5″ by 1″. The means for input  393  is preferably a push button switch that controls all luminaires simultaneously and turns them all on or off. The sensor  392  is preferably an Infrared (IR) occupancy sensor with a 8′ maximum range. It is preferred to connect the sensor to the power supply (see  FIG. 3A ) via the connector  394  and cable  395  (see  FIG. 3A ). The connector  394  is preferably RJ11. Alternate embodiments use a RJ45 connector or other data transmission method. 
         [0067]      FIG. 4A  illustrates a simplified functional drawing of a power supply, in accordance with the instant invention. Specifically,  FIG. 4A  clarifies the functional design of the power supply. The power supply is comprised of a housing  401 ; circuit board  405 ; sensor connector  403 ; DC connectors  404   a - g ; control circuit  410 ; indicator  408 ; and AC connector  407 . The power supply further comprises a means for electrically connecting the AC connector  407  to the control circuit  410 , a second means for electrically connecting the indicator  408  to the control circuit  410 , a third means for connecting the sensor connector  403  to the control circuit  410 , and a forth means for connecting the DC connectors  404   a - g  to the control circuit. 
         [0068]    The circuit board  405  is mounted inside the housing  401  and further provides physical support for all other items listed above that comprise the power supply. The DC connectors  404   a - g  provide a means to connect to luminaires (not shown) and provide power for LEDs contained in the luminaires (not shown). The preferred embodiment uses standard DC power jacks for this purpose. The sensor connector  402  provides a means to connect to the means for controlling the power supply (see  FIG. 3A ). The AC connector  407  is preferred to be a plug-type rather than hardwired, which allows the power supply to be easily installed. The AC connector  407  is preferred to be a smaller size than a standard NEMA wall outlet plug to allow the AC power cord (see  FIG. 3A ) to fit through smaller spaces. 
         [0069]      FIG. 4B  illustrates a simplified functional drawing of task or accent luminaire, in accordance with the instant invention. Specifically,  FIG. 4B  clarifies the functional design of the luminaire. The luminaire is comprised of a base  422 ; a connector  421 ; a first articulator  423 ; an arm  424 ; a second articulator  425 ; a head  426 ; a circuit board  429 ; a plurality of LEDs  430 ; a thermal path  428 ; a heat sink  427 ; and an electrical path  431 . The base  422  provides support for the luminaire. It is preferred to be substantially flat and heavy to provide stability and support for the luminaire. In other embodiments the base  422  may clamp to a table (not shown) or integrate directly with furniture systems (not shown). The first articulator  423  and second articulator  425  are preferred to provide 2 or 3 degrees of freedom of movement. In combination, the articulators  423 ,  425  allow the head  426  to be positioned freely in the space. In the preferred embodiment, the arm  424  raises the head  426  away from the work surfaces and allows the light emitted from the LEDs  430  to illuminate the work area. In other embodiments, a second arm and third articulator provide additional motion. 
         [0070]    The connector  421  is designed to allow luminaires of the same power rating to interface with the rest of the device (see  FIG. 3A ) in an identical fashion. This provides the user with flexibility in their luminaire choice and allows them to select appropriate luminaires for their work space. In the preferred embodiment, the electrical path  431  comprises two wires that bring electrical power from the connector  421  to the circuit board  429 . The circuit board  429  provides mechanical support for the LEDs  430  and additionally provides electrical connection from the electrical path  431  to the LEDs  430 . In the preferred embodiment, the circuit board  429  contains further power regulation circuitry to drive the LEDs  430  at a constant current (see  FIG. 2A ). The thermal path  428  connects the circuit board  429  to the heat sink  427  and ensures the LEDs  430  are maintained at an appropriate temperature. In the preferred embodiment, the temperature is 40 degrees C.  FIG. 4C  illustrates a simplified functional drawing of a wall wash luminaire, in accordance with the instant invention. Specifically, the wall wash luminaire comprises: a body  441 ; an electrical path  442 ; a first connector  443 ; a second connector  451 ; a first, second, and third circuit board  444 ,  447 ,  450 ; a first, second, and third thermal path  445 ,  446 ,  448 ; a first and second set of wires  455 ,  453 ; a first, second, and third set of LEDs  456 ,  454 ,  452 ; a reflector  449 ; and an electrical path  442 . 
         [0071]    The body  441  provides mechanical support for the reflector  449 . The reflector  449  supports the first, second and third circuit boards  444 ,  447 ,  450 . The connectors  443 ,  451  are identical and allow connection from either end. In the preferred embodiment, daisy chaining of multiple luminaires is prevented by both mechanical and electrical means. The means from connecting the luminaire to the power supply (see  FIG. 3A ) is asymmetric and will not connect from one luminaire to a second luminaire (see  FIG. 3A ). The circuit boards  444 ,  447 ,  450  provide support and electrical connections for the sets of LEDs  456 ,  454 ,  452 . Further, the first circuit board  444  contains circuitry to convert power from the power supply into constant current power to the LEDs. This power is transferred from the first circuit board  444  to the second and third circuit boards  447 ,  450  through wires  455 ,  453 . The wires further electrically connect the first connector  443  to the second connector  451 , as shown by the electrical path  442 . 
         [0072]    The sets of LEDs  456 ,  454 ,  452  generate heat (not shown), which is transferred to the circuit boards  444 ,  447 ,  450 . The heat is further transferred to through the thermal paths  445 ,  446 ,  448  to the reflector  449 . The reflector  449  convects and radiates the heat to the environment. In the preferred embodiment, the LEDs are maintained at or below 40 degrees C. 
         [0073]    The current embodiment shows a first, second, and third circuit board. In alternate embodiments additional circuit boards (not shown) are added to further disperse the light and increase the uniformity of illumination on the task surface. In these alternate embodiments, five evenly spaced circuit boards (not shown) are used to light a 4′ long surface. Each circuit board (not shown) supports and electrically connects two 0.5 Watt white LEDs (not shown). In other alternate embodiments, luminaires are made with increased power, using four 0.5 Watt white LEDs per circuit board (not shown). In further embodiments, luminaires are shortened to provide illumination for 2′ or 3′ long surfaces (not shown). It will be clear from the discussions above and below that luminaires can include any other type of LEDs or combination of LEDs with any suitable power requirement including, for example, 1-Watt white LEDs. 
         [0074]      FIG. 4D  illustrates a simplified functional drawing of a controller, in accordance with the instant invention. Specifically, the controller comprises: a body  461 ; a circuit board  462 ; an IR sensor  463 ; a control circuit  465 ; a connector  467 ; and a switch  469 . The controller further comprises: a means for connecting the IR sensor  463  to the control circuit  465  ( 464 ), a second means for connecting the switch  469  to the control circuit  46  ( 468 ); and a third means for connecting the connector  467  to the control circuit  465  ( 466 ). The body  461  provides support for the circuit board  462  and encloses all sensitive components. The connector  467  is typically a RJ11 connection and connects to the power supply (see  FIG. 3A ). The preferred embodiment uses the IR sensor  463  to detect occupancy of the work space. A signal (not shown) indicating the state of the occupancy is sent to the control circuit  465  using the means  464 . A second signal (not shown) indicating the state of the switch  469  is sent to the control circuit  465  using the second means  468 . The control circuit  465  provides power for the IR sensor  463  through the means  464  and processes the signals (not shown). The IR sensor  463  further sends signals to the power supply via the third means  466  and the connector  467  (see  FIG. 3A ). 
         [0075]    The controller takes user input from the switch  469  and combines the input with information from the IR sensor  463 . The controller then commands the power supply (see  FIG. 3A ) to turn the luminaires on or off. In alternate embodiments, the controller contains other sensors including, but not limited to, temperature, time, acceleration, or humidity sensor. In further alternate embodiments, the controller is integrated into the power supply. In the preferred embodiment, the sensor is place in an accessible location such that the user can depress the switch  469  and the IR sensor  463  can detect the user. 
         [0076]      FIG. 5A  illustrates a light distribution graph of the configured lighting provided by a task or accent luminaire, in accordance with the instant invention. A task luminaire will typically provide two to three more times the light output of an accent light, but the distribution of the light will be fairly similar. In other embodiments, the distribution graph is more asymmetric to provide a larger amount of illumination at a greater distance from the luminaire in the direction away from the luminaire base. 
         [0077]      FIG. 5B  illustrates a light distribution graph of the configured lighting provided by a wall wash luminaire, in accordance with the instant invention. In other embodiments this distribution may be further smoothed using diffusers or reflectors. Additionally, in other embodiments the wall wash luminaire may provide more or less total light output by using proportionally more or less LEDs. 
         [0078]      FIG. 6A  illustrates a lamp head or luminaire head configuration  600 , in accordance with the instant invention. The lamp head or luminaire head configuration  600  includes a finned lamp head  601  that is made from a thermally conductive material, such as metal. The finned lamp head  601  has a heat sink portion  611 . Embedded or seated within the heat sink portion  611  there is a light emitting diode or a light emitting diode array  609 . 
         [0079]    The light emitting diode or light emitting diode array  609  is configured to emit light from the finned lamp head  601 , as indicted by the arrows  652  ( FIG. 6B ). In accordance with the embodiments of the invention the lamp head or luminaire head configuration  600  includes an articulated neck portion  603  for attaching the finned lamp head  601  to a stem portion  651  and/or other support structure, which supports or suspends the finned lamp head  601  over a work space. The lamp head or luminaire head configuration  600 , in accordance with further embodiments of the invention, is equipped with a clip or any other suitable attachment feature (not shown) for attaching the finned lamp head  601  to a shelf, a desk, or other workspace surface. 
         [0080]    Still referring to  FIG. 6A , the finned lamp head  601  has any number of fins  613 ,  615 ,  613 ′ and  615 ′. The fins  613 ,  615 ,  613 ′ and  615 ′ are also made of .a thermally conductive material, such as metal. The fins  613 ,  615 ,  613 ′ and  615  are separated by a distance  619  sufficient to allow laminar convection flow of air between the fins  613 ,  615 ,  613 ′ and  615  under normal conditions and thereby cool the light emitting diode or the light emitting diode array  609 . Preferably, the fins  613 ,  615 ,  613 ′ and  615  are separated by a distance  619  that is 1.0 mm or greater. The finned lamp head  601  is, therefore, also referred to as a convection air cooled light emitting diode luminaire. Preferably, the fins  613 ,  615 ,  613 ′ and  615 ′ are positioned on or extend outward from two or more opposed sides of the heat sink portion  611  of the finned lamp head  601 . However, it will be clear to one skilled in the art from the discussion herein that fins, such as the fins  613 ,  615 ,  613 ′ and  615 ′, can completely surround a periphery of the heat sink portion  611  of the finned lamp head  601 , protrude from a top surface of the finned lamp head  601 , or protrude from a lower surface of the heat sink portion  611  of the finned lamp head  601 , or any combination of configurations thereof. Also it will be understood that the while the finned lamp head  601  is shown in  FIG. 6A  as being rectangular shaped, the finned lamp head  601  can be any shape, including but not limited to, round shaped, oval shaped, square shaped, and triangular shaped. 
         [0081]      FIG. 6B  shows a task lamp system  650  in accordance with the embodiments of the invention. The task lamp system  650  includes a task lamp  654  with a finned lamp head  601 , such as described above. The task lamp  654 , in accordance with the embodiments of the invention, includes an articulated neck potion  603  that allows the finned lamp head  601  to be adjusted. In accordance with further embodiments of the invention, the task lamp  654  also includes a stem portion  651  that is connected to a base portion  653  for supporting the finned lamp head  601  over a work space, such that the finned lamp head  601  can emit light over a work space, as indicated by the arrows  652 , when the task lamp  654  is powered on. In accordance with the embodiments of the invention, the stem portion  651  is coupled to the base portion  653  through a swivel hinge or a swivel joint  655  or any other suitable means. 
         [0082]    Still referring to  FIG. 6B , the task lamp system  650  further includes a power supply  671 , such as described in detail above. The power supply  671  is configured to coupled to a power outlet through a power cord  667  and provide power to the task lamp  654  as well as other luminaires or task lamps (not shown) electrically coupled to the power supply  671 . The task lamp  654  is electrically coupled to the power supply  671  through an interconnect cable  673  and an interconnect  675 . The task lamp system  650  preferably also includes an occupancy sensor  661  that is also powered by the power supply  671 . The occupancy sensor  661  is electrically coupled to the power supply  671  through an interconnect cable  663  and an interconnect  665 . In operation the occupancy sensor  661  instructs the power supply  671  to control the task lamp  654  in response to detecting a person or persons at or near an area around the task lamp system  650 . It will be clear to one skilled in the art that the occupancy sensor  661  can alternatively have its own power supply (not shown) and communicate with the power supply  671  to operate the task lamp  654  in response to detecting a person or persons at or near the area around the task lamp system  650  using wireless communication techniques. 
         [0083]      FIGS. 6C-F  show different geometries or designs of finned lamp head or luminaire head configurations, in accordance with embodiments of the instant invention.  FIG. 6C  shows a front view of the flat finned lamp head  601 , such as shown in  FIGS. 6A-B ;  FIG. 6D  shows a front view of a curved or contoured finned lamp head  602 ;  FIG. 6E  shows a front view of an angled or bent finned lamp head  604 ; and  FIG. 6F  shows a front view of a squared or right angle finned lamp head  606 . It will be clear to one skilled in the art that the finned lamp head of the present invention can have any number of different geometries or designs and combinations of geometries or designs, including those described with reference  FIGS. 6C-F  above. 
         [0084]    The current invention also discloses a system for providing task lighting. The system comprises a plurality of luminaires configured to output lighting in a work space, a power supply to limit the total power used in the work space, means for connecting the luminaires to the power supply, and means for controlling the power supply and luminaires. The plurality of luminaires comprises LEDs to provide illumination and circuitry to appropriately power the LEDs. In other embodiments, the circuitry is integrated into the power supply. 
         [0085]    In addition, the current invention also disclosed a method of making task lighting systems. The preferred method comprises providing luminaires, power supply, and controls. The method further comprises limiting the power supplied to a work space through choice of a power supply. Additionally, the method comprises choosing task-specific luminaires to match the requirements of the work space. For example, a cubical with binder bins could utilize an under-counter luminaire, while a open desk in a private office would exchange the under-counter luminaire for a task luminaire 
         [0086]    There have been attempts to light work environments to low levels of ambient lighting. These have been resisted for a variety of reasons, one of which is the lack of adequate task lighting. Uncertain energy consumption, quality, and price of task lamps make them difficult to specify when designing a building. Poor standardization between different luminaires adds to difficulties when installing additional task lighting after buildings have been occupied. Further, maintaining a wide variety of task lighting solutions can be difficult and expensive. 
         [0087]    In contrast to unregulated task lighting connected to a wall outlet, task lighting systems in accordance with the embodiments of the invention provide highly efficient and effective distribution of light across a work space. Further, the use of LEDs allows a much wider dispersion of light across the work space than traditional fluorescent sources. The modular nature of the current invention assures that all users in a building will be able to customize a solution to fit their work habits and personal environment. At the same time, the limits on the power supply ensure the total energy usage of the building can be planned in advance and the modularity of the system also allows easy maintenance and upgrades. Further, as tenants of a building change, the space can be easily reconfigured. 
         [0088]    The present invention has been described in terms of specific embodiments incorporating details to facilitate the understanding of the principles of construction and operation of the invention. Such references herein to specific embodiments and details thereof is not intended to limit the scope of the claims appended hereto. It will be apparent to those skilled in the art that modifications may be made in the embodiment chosen for illustration without departing from the spirit and scope of the invention.