HK1251642B - Single-emitter lighting device that outputs a minimum amount of power to produce integrated radiance values sufficient for deactivating pathogens - Google Patents

Description

Single-emitter lighting devices that output the minimum amount of power to produce an overall radiation sufficient to inactivate pathogens

Technical Field

The present disclosure relates generally to lighting devices and, more particularly, to a single-emitter lighting device that outputs a minimal amount of power to inactivate pathogens.

Background Art

Pathogens such as viruses, bacteria and fungi are the cause of many diseases or infections that affect humans, animals and plants, including some very dangerous and potentially fatal diseases and infections. Environments such as health care environments (such as hospitals) and restaurants are particularly prone to the spread or diffusion of such pathogens. In fact, health care associated infections (HAIs) caused by pathogens such as methicillin-resistant Staphylococcus aureus (MRSA) and Clostridium difficile (C. difficile), which are spread by contact between people and skin shedding in health care environments, are an increasingly dangerous problem in the health care industry. According to the Centers for Disease Control and Prevention, HAIs cause at least 1.7 million illnesses and 99,000 deaths in acute care hospitals in the United States alone each year. Pathogens may also cause food products (such as fruits and vegetables) to deteriorate and lead to the loss of goods and raw materials in various industrial processes such as chemical processing, brewing and distilling, food packaging and other processes that require a pollution-free environment.

Large amounts of resources have been invested to prevent and control the pathogen in these environments, but so far, these resources have not yet produced the desired result. Proven methods for some existing control pathogens such as those relating to hygiene require a large amount of labor, are difficult to monitor, and the most important thing is that there is little effect (as, only temporarily effective, only making some pathogen inactivations). Though other known methods for control pathogens such as those relating to ultraviolet light, ozone and chemical fumigation are effective, they are poisonous to the human body. Therefore, the environment requiring decontamination must be airtight and cannot be used during the process.

Summary of the Invention

One aspect of the present disclosure provides a lighting device configured to inactivate dangerous pathogens (such as MRSA bacteria) in an environment. The lighting device includes at least one lighting element configured to provide light. At least a first component of the light includes light having a wavelength between 400 nm and 420 nm, and at least a second component of the light includes light having a wavelength greater than 420 nm. The first component of the light has a minimum overall irradiance of 0.05 mW/cm ² , measured from any unobstructed point in the environment 1.5 m from any point on any outermost light-emitting surface of the lighting device.

Another aspect of the present disclosure provides a lighting device configured to inactivate dangerous pathogens (such as MRSA bacteria) in an environment. The lighting device includes at least one light-emitting element and at least one light conversion element, the at least one light-emitting element being configured to emit light having a wavelength between 400nm and 420nm. At least a first component of the light emitted by the at least one light-emitting element passes through the at least one light conversion element without change, and at least a second component of the light emitted by the at least one light-emitting element is converted to light having a wavelength greater than 420nm. The first component of the light has a minimum overall irradiance of 0.05mW/ ^cm2 , the minimum overall irradiance being measured from any unobstructed point in the environment 1.5m from any point on any outermost light-emitting surface of the lighting device.

Another aspect of the present disclosure provides a method for inactivating dangerous pathogens (such as MRSA bacteria) in an environment. The method includes providing light from at least one lighting element of a lighting device installed in the environment. At least a first component of the light has a wavelength between 400 nm and 420 nm and has a minimum overall irradiance of 0.05 mW/ ^cm2 , the minimum overall irradiance being measured from any unobstructed point in the environment 1.5 m from any point on any outermost light-emitting surface of the lighting device, and at least a second component of the light has a wavelength greater than 420 nm.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings and the following detailed description are incorporated into and form a part of this specification and are used to further illustrate embodiments including the concepts of the claimed embodiments and to explain the various principles and advantages of those embodiments. In the accompanying drawings, like reference numerals refer to the same or functionally similar elements throughout the various views.

1 is a schematic diagram of a lighting system constructed in accordance with the teachings of the present disclosure and for use in environments susceptible to the spread of pathogens.

2 is a schematic diagram of a portion of the environment of FIG. 1 including a lighting device constructed in accordance with the teachings of the present disclosure and configured to inactivate pathogens in the portion of the environment.

FIG3A shows the CIE 1976 chromaticity diagram.

3B is a close-up partial view of the graph of FIG. 3A , illustrating a series of curves of white visible light that may be output by the lighting device of FIG. 2 such that the lighting device may provide visually attractive, non-offensive white light.

FIG. 4A is a plan view of an exemplary variation of the lighting device of FIG. 2 .

4B is a rear perspective view of the lighting device of FIG. 4A .

4C is a bottom view of the lighting device of FIG. 4A and FIG. 4B , illustrating a first plurality of light-emitting elements configured to inactivate pathogens.

4D is a partial close-up view of a portion of the lighting device of FIG. 4C .

5A is a perspective view of the lighting device of FIGs. 4A-4D installed in a receiving structure of an environment.

FIG5B is a cross-sectional view of FIG5A .

6A is a bottom view of another exemplary variation of the lighting device of FIG. 2 , illustrating a second plurality of light-emitting elements configured to inactivate pathogens.

6B is a partial close-up view of a portion of the lighting device of FIG. 6A .

FIG7 shows another exemplary variation of the lighting device of FIG2 ;

FIG8 shows another exemplary variation of the lighting device of FIG2 ;

FIG9A is a perspective view of another exemplary variation of the lighting device of FIG2 ;

FIG9B is a cross-sectional view of the lighting device of FIG9A ;

9C is another cross-sectional view of the lighting device of FIG. 9A , illustrating a first plurality of light-emitting elements configured to emit light that inactivates pathogens, and a second plurality of light-emitting elements configured to emit light that mixes with the light emitted by the first plurality of light-emitting elements to produce visually appealing visible light;

FIG9D is a block diagram of various electrical components of the lighting device of FIG9A ;

FIG9E illustrates visually attractive white visible light that may be output by the lighting device of FIG9A when the environment is occupied;

FIG9F illustrates disinfecting light that may be output by the lighting device of FIG9A when the environment is unoccupied;

FIG9G illustrates one embodiment of how the lighting device of FIG9A-9D may be controlled in response to various dimming settings;

FIG10A is a perspective view of another exemplary variation of the lighting device of FIG2 ;

FIG10B is similar to FIG10A , but with the lens of the lighting device removed to illustrate multiple lighting elements;

FIG10C is a top view of FIG10B;

FIG10D is a close-up view of one of the plurality of lighting elements of FIG10B and FIG10C;

FIG11A illustrates one embodiment of the radiant power distribution of a lighting device constructed according to the teachings of the present disclosure;

FIG11B illustrates a graph of one embodiment of light distribution as a function of vertical angle from the horizontal for a lighting device constructed in accordance with the teachings of the present disclosure;

FIG11C illustrates a graph of another embodiment of light distribution as a function of vertical angle from the horizontal for a lighting device constructed according to the teachings of the present disclosure;

FIG11D illustrates a graph of another embodiment of light distribution as a function of vertical angle from the horizontal for a lighting device constructed in accordance with the teachings of the present disclosure;

FIG. 11E illustrates a graph of another embodiment of light distribution as a function of vertical angle from the horizontal for a lighting device constructed in accordance with the teachings of the present disclosure;

FIG11F depicts a graph of luminous flux for the light distribution diagram of FIG11B ;

FIG11G depicts a graph of luminous flux for the light distribution diagram of FIG11C ;

FIG11H depicts a graph of luminous flux for the light distribution diagram of FIG11D ;

FIG11I depicts a graph of luminous flux for the light distribution diagram of FIG11E ;

FIG12 is a flow chart of an exemplary method for providing a sufficient dose of light over a period of time to inactivate dangerous pathogens throughout a volumetric space; and

13 is a schematic diagram of an exemplary variation of a control device constructed in accordance with the teachings of the present disclosure.

DETAILED DESCRIPTION

Figure 1 depicts a lighting system 50 that can be implemented or included in an environment 54, such as, for example, a hospital, doctor's office, exam room, laboratory, nursing home, health club, retail store (such as a grocery store), restaurant, or other space or building, or portion thereof, in which it is desirable to provide illumination while reducing and ideally eliminating the presence and spread of the aforementioned pathogens.

The lighting system 50 shown in FIG1 generally includes a plurality of lighting devices 58, a plurality of bridge devices 62, a server 66, and one or more client devices 70, which are configured to connect to the server 66 via one or more networks 74. Of course, the lighting system 50 may include more or fewer components and/or different components if desired. For example, the lighting system 50 does not necessarily need to include the bridge device 62 and/or the client device 70.

Each lighting device 58 is installed in or at the environment 54 and includes one or more light-emitting components, such as light-emitting diodes (LEDs), fluorescent lamps, incandescent lamps, laser diodes, or plasma lamps, which, when powered, (i) illuminate the area near or around the corresponding lighting device 58 in the environment 54 and (ii) emit a sufficient dose of visible light to inactivate pathogens in the illuminated area, as described below. In one variation, the lighting devices 58 can be uniformly constructed. In another variation, the lighting devices 58 can vary in type, shape, and/or size. For example, the lighting system 50 can employ various combinations of the different lighting devices described herein.

A bridging device 62, at least in this embodiment, is located at the environment 54 and is communicatively connected (e.g., via a wired and/or wireless connection) to one or more of the lighting devices 58. In the lighting system 50 shown in FIG1 , four bridging devices 62 are utilized, with each bridging device 62 connected to three different lighting devices 58. In other embodiments, more or fewer bridging devices 62 may be connected to more or fewer lighting devices 58.

The server 66 can be any type of server, such as, for example, an application server, a database server, a file server, a network server, or other server. The server 66 can include one or more computers and/or can be part of a larger server network. The server 66 is communicatively connected to the bridge device 62 (e.g., via a wired and/or wireless connection). The server 66 can be located remotely from the lighting devices 58 and the client devices 70 (e.g., in the "cloud") and can include one or more processors, controller modules (e.g., a central controller 76), etc., configured to facilitate various communications and commands between the client devices 70, the bridge device 62, and the lighting devices 58. In this way, the server 66 can generate commands or instructions and send the commands or instructions to the lighting devices 58 to implement various sets of lighting settings corresponding to the operation of the lighting devices 58. Each set of lighting settings may include various parameters or settings, including, for example, spectral characteristics, operating modes (e.g., inspection mode, disinfection mode, mixed mode, night mode, day mode, etc.), dimming levels, output wattage, intensity, timeouts, and/or the like, wherein each set of lighting settings may also include a schedule or table that specifies which settings should be used based on the time of day, day or week, natural light levels, occupancy, and/or other parameters. The server 66 may also receive and monitor data from the lighting devices 58 via the bridge device 62, such as operating status, light emission data (e.g., what light is emitted and when it is emitted), hardware information, occupancy data, daylight levels, temperature, power consumption, and dosage data. In some cases, this data may be recorded and used to form or generate reports, such as reports indicating the characteristics of light emitted by one or more of the lighting devices 58. These reports may be used, for example, to demonstrate that the environment 54 emits a sufficient dose of light to inactivate pathogens in the illuminated area at or during various time periods.

The network 74 may be any type of wired network, wireless network, or both, such as a wide area network (WAN), a local area network (LAN), a personal area network (PAN), or other network. The network 74 may facilitate any type of data communication via any standard or technology, such as GSM, CDMA, TDMA, WCDMA, LTE, EDGE, OFDM, GPRS, EV-DO, UWB, IEEE 802 including Ethernet, WiMAX, WiFi, and others.

The client device 70 can be any type of electronic device, such as a smartphone, desktop computer, laptop computer, tablet computer, phablet, smartwatch, smart glasses, wearable electronics, pager, personal digital assistant, or any other electronic device, including a computing device configured for wireless radio frequency (RF) communication. The client device 70 can support a graphical user interface (GUI), wherein a user of the client device 70 can use the GUI to select various operations, change settings, view operating status and reports, perform updates, generate email/text alert notifications, and/or perform other functions. The client device 70 can transmit any updated lighting settings to the lighting device 58 via the network 74, server 66, and bridge device 62 for implementation and/or storage on the lighting device. The client device 70 can facilitate data communication via a gateway access point, which can be connected to the bridge device 62. In one embodiment, the gateway access point can be a cellular access point comprising a gateway, an industrial Ethernet switch, and a cellular router integrated in a sealed housing. Additionally, the gateway access point may be secured using HTTPS with a self-signed certificate to access web services and may push/pull data between various websites, one or more bridge devices 62 , and the lighting devices 58 .

2 illustrates a healthcare environment 100 that includes one of the lighting fixtures 58 in the form of a lighting fixture 104 constructed in accordance with the present disclosure. The healthcare environment 100, which may be, for example, or include, an examination room, an operating room, a restroom, a hallway, a waiting room, a closet or other storage area, a clean room, or portions thereof, is often susceptible to the spread of dangerous pathogens, as described above.

Experimental studies have shown that narrow spectrum visible light (e.g., light having a wavelength between 400 nm and 420 nm) can effectively inactivate (or destroy) dangerous pathogens when delivered in specifically configured doses at sufficiently high power levels (e.g., above 3,000 mW). However, these doses can easily cause disruptive or objectionable aesthetic effects in the environment into which they are delivered. For example, when a surgical procedure is being performed in the healthcare environment 100, these doses may provide undesirable light output. Therefore, it has proven difficult to incorporate these doses into lighting devices that can simultaneously inactivate pathogens and illuminate an environment (e.g., the healthcare environment 100) in a non-objectionable manner. Instead, narrow spectrum visible light doses are typically delivered only when the environment is unoccupied, thereby severely limiting the inactivation potential of such lighting devices.

The lighting device 104 described herein is configured to emit a dose of narrow spectrum visible light at a sufficiently high power level to effectively inactivate dangerous pathogens in the healthcare environment 100 (or other environment), while at the same time providing visible light sufficient to illuminate the environment 100 (or other environment) in a safe and non-objectionable manner.

More specifically, the lighting device 104 provides or emits (e.g., outputs, emits) at least 3,000 mW (or 3 W) of disinfecting light to the environment 100, the disinfecting light having a wavelength within the range of about 380 nm to about 420 nm, and more particularly, a wavelength between 400 nm and 420 nm. It will be understood that light doses having wavelengths within this range but emitted at power levels below 3,000 mW are generally ineffective in inactivating dangerous pathogens. The lighting device 104 can, for example, provide or emit 3,000 mW, 4,000 mW (or 4 W), 5,000 mW (or 5 W), 6,000 mW (or 6 W), 7,000 mW (or 7 W), 10,500 mW (or 10.5 W), or some other level of disinfecting light above 3,000 mW. The lighting device 104 also provides or emits a disinfecting light level such that any exposed surface within the environment 100 has or achieves a desired minimum power density when the lighting device 104 is used for deactivation, thereby ensuring that the environment 100 is adequately disinfected. The desired minimum power density is the minimum power, measured in mW, received by any exposed surface per unit area, measured in cm ^2. When measured or determined over time (the period of time during which the lighting device 104 is used for deactivation), this minimum power density within the applicable visible light bandwidth can be referred to herein as the minimum overall irradiance, measured in mW/cm ² . The minimum overall irradiance of the disinfecting light provided by the lighting device 104—in this embodiment, the minimum overall irradiance is measured from any exposed surface or unobstructed point in the environment 100 1.5 m from any point on any outermost light emitting surface 102 of the lighting device 104, but in other embodiments the minimum overall irradiance may be measured from a different distance from any outermost light emitting surface 102, from the lowest point, from any unobstructed point, or from some other point in the environment 100—is typically equal to at least 0.01 mW/cm . The minimum overall irradiance may be, for example, equal to 0.02 mW/ ^cm , 0.05 mW/ ^cm , 0.1 mW/cm , 0.15 mW/ ^cm , 0.20 mW/ ^cm , 0.25 mW/ ^cm , 0.30 mW/ ^{cm ,} or some other value greater than 0.01 mW/ ^cm .

At the same time, the lighting device 104 provides a visible light output that is perceived by people (e.g., patients, personnel) in or around the environment 100 as white light, having properties that have been shown by research to be aesthetically pleasing or at least non-objectionable to humans, and having a component that includes narrow-spectrum visible disinfecting light. Although the exact properties of the white light may vary depending on the specific application, these properties generally include one or more of the following: (1) a desired color rendering index, such as a color rendering index greater than 70, greater than 80, or greater than 90; (2) a desired color temperature, such as a color temperature between about 1500 degrees Kelvin and 7000 degrees Kelvin, more particularly, a color temperature between about 1800 degrees Kelvin and 5000 degrees Kelvin, a color temperature between about 2100 degrees Kelvin and 6000 degrees Kelvin, a color temperature between about 2700 degrees Kelvin and 5000 degrees Kelvin, or some other temperature or temperature range within these ranges, partially outside these ranges, or entirely outside these ranges; or (3) a desired chromaticity.

Chromaticity can be described relative to any number of different chromaticity diagrams, such as, for example, the 1931 CIE chromaticity diagram, the 1960 CIE chromaticity diagram, or the 1976 CIE chromaticity diagram shown in FIG. 3A . Thus, aesthetically pleasing white light output by lighting device 104 can be described as having properties associated with or based on these chromaticity diagrams. As shown, for example, in FIG. 3B , the white light output by lighting device 104 can have u′, v′ coordinates on the 1976 CIE chromaticity diagram ( FIG. 3A ) that lie on any number of different curves associated with the Planckian locus 105 defined by the ANSI C78.377-2015 color standard. The ANSI C78.377-2015 color standard generally describes a range of color mixtures that form pleasing or visually appealing white light. This range is generally defined by the Planckian locus 105, also known as the blackbody curve, with some deviation above or below the Planckian locus 105 measured in units of Duv. Depending on the given application, the different curves on which the u', v' coordinates of the white light output may lie deviate from the Planckian locus 106 at different values of Duv. The white light may, for example, lie on curve 106A that is 0.035 Duv above the Planckian locus 105, on curve 106B that is 0.035 Duv (-0.035 Duv) below the Planckian locus 105, on curve 107 that is 0.02 Duv (-0.02 Duv) below the Planckian locus 105, on a curve that is 0.02 Duv above the Planckian locus, or on some other curve between 0.035 Duv above and 0.035 Duv below the Planckian locus 105.

The lighting device 104 is, in some cases, completely enclosed, which facilitates cleaning by, for example, preventing pathogens from harboring on or in internal components of the lighting device 104, which would otherwise be difficult to achieve with certain configurations of narrow-spectrum visible light. In other words, in these cases, no interior surfaces of the lighting device 104 are exposed to the environment 100 surrounding the lighting device 104, preventing dangerous pathogens from residing on surfaces that are inaccessible to the narrow-spectrum visible light.

As will be described herein, lighting device 104 includes one or more light-emitting elements, such as light-emitting diodes (LEDs), configured to emit light as desired. Lighting device 104 may optionally include one or more reflectors, one or more lenses, one or more diffusers, and/or one or more other components. In some embodiments, such as when LEDs are employed in the lighting device, lighting device 104 may include means for maintaining the junction temperature of the LEDs below the LED's maximum operating temperature. Means for maintaining the junction temperature may include, for example, one or more heat sinks that spread heat to a printed circuit board coupled to the LEDs, a constant current driver topology, a thermal feedback system that feeds back heat to one or more drivers (powering the LEDs) via an NTC thermistor, or other means for reducing the LED drive current when a temperature rise is sensed. Lighting device 104 may also include an occupancy sensor 108, a daylight sensor 112, one or more communication modules 116, and one or more control components 120, such as a local controller. Lighting device 104 may optionally include one or more additional sensors, such as two occupancy sensors 108, a sensor that measures the light output by device 104, and the like.

In this variation, occupancy sensor 108 is an infrared (IR) motion sensor that detects motion within a predetermined range of lighting device 104 or at a predetermined distance (e.g., 50 feet) from the lighting device to identify (or help identify) whether environment 100 is occupied or unoccupied (i.e., unoccupied), and whether the environment has been occupied or unoccupied for a period of time (e.g., a predetermined period of time, such as 15 minutes, 30 minutes, etc.). Occupancy sensor 108 can continuously monitor environment 100 to determine whether it is occupied. In other variations, occupancy sensor 108 can be a different type of sensor that utilizes different occupancy detection technologies or techniques to identify (or help identify) whether environment 100 is occupied or unoccupied, and whether the environment has been occupied or unoccupied for a period of time, such as an ultrasonic sensor, a microwave sensor, a _CO2 sensor, or a thermal imaging sensor. In some variations, multiple occupancy sensors 108 that detect occupancy using different detection technologies or techniques can be employed to provide more robust detection. For example, lighting device 104 may include an infrared motion sensor and a CO2 sensor that utilize different technologies or techniques to detect occupancy. Meanwhile, daylight sensor 112 is configured to detect natural light within a predetermined range of lighting device 104 or a predetermined distance (e.g., 50 feet) from the lighting device to identify whether it is day or night (and therefore whether environment 100 is occupied or unoccupied).

In response to occupancy data obtained by occupancy sensor 108 and/or natural light data obtained by daylight sensor 112, lighting device 104 can be controlled by local controller 120 (or other control component) to emit visible light of various characteristics or having various characteristics. For example, lighting device 104 can be controlled to output visible light consisting only of a specific configuration of narrow-spectrum visible light in response to data indicating that environment 100 is idle (i.e., unoccupied). In some cases, narrow-spectrum visible light is only output after lighting device 104 determines that environment 100 has been idle for a predetermined period of time (e.g., 30 minutes), thereby providing a failsafe to ensure that environment 100 is indeed idle. Lighting device 104 can be communicatively connected to and controlled by remotely located server 66 (and remotely located client device 70) via communication module 116, and/or communicatively connected to other lighting devices 58. In this way, the lighting device 104 can transmit data such as operating status (e.g., operating mode), light emission data, hardware information, occupancy data, daylight level, output wattage, temperature, power consumption to the server 66 and/or other lighting devices 58, and can receive operating instructions (e.g., turn on, turn off, provide light with different spectral characteristics, switch between operating modes) and/or other data (e.g., operating data from or about other lighting devices 58) from the server 66, other lighting devices 58 and/or client device 70.

It will be appreciated that the lighting devices 104 may be manually controlled (e.g., by a user of the lighting devices 104) and/or automatically controlled in response to other settings, parameters, or data instead of, or in addition to, the data obtained by the occupancy sensors 108 and/or daylight sensors 112. The lighting devices 104 may be partially or fully controlled by the local controller 120 (or other control component) in response to an operating mode, dimming level, schedule or table, or other parameters or settings received by the local controller 120 (or other control component).

In some variations, such as the one shown in FIG. 2 , the lighting device 104 may include a dose or deactivation feedback system 124 that monitors and records the amount and frequency of the dose delivered by the lighting device 104. While the dose feedback system 124 may be implemented using other components in the lighting device 104 (e.g., a suitable processor and memory) or via the server 66, in this variation, the local controller 120 implements the dose feedback system 124. In any case, the dose feedback system 124 achieves the aforementioned objectives by monitoring and recording various parameters or settings of the lighting device 104 and parameters or settings associated with the lighting device over time. More specifically, the dose feedback system 124 monitors and records the spectral characteristics, output wattage, wavelength, and/or intensity of the light (or its components) emitted by the lighting device 104, the minimum overall irradiance of the disinfecting narrow-spectrum visible light provided by the lighting device 104, occupancy data obtained by the occupancy sensor 108, the amount of time the lighting device 104 spends in various operating modes (e.g., inspection mode), dimming levels, and the like. For example, the dose feedback system 124 monitors and records when the lighting device 104 emits visible light that includes disinfecting narrow-spectrum visible light (i.e., light with a wavelength between 400nm and 420nm) or consists solely of disinfecting narrow-spectrum visible light, as well as the level and density (and more particularly, the minimum overall irradiance) of the disinfecting narrow-spectrum visible light emitted during these times. Based on the parameters or settings of the lighting device 104, the dose feedback system 124 (and/or the operator of the lighting device 104) can determine the number and frequency of the deactivating dose emitted by the lighting device 104. Alternatively or additionally, the dose feedback system 124 can provide the recorded data to the server 66 (via the communication module 116), which can in turn determine the number and frequency of the deactivating dose emitted by the lighting device 104. In some cases, the dose feedback system 124 and/or the server 66 can generate periodic reports that include the data obtained and/or information about the determination of the deactivating dose. When the dose feedback system 124 generates these reports, they can be transmitted to the server 66 or any other component via the communication module 116. In any case, the dose feedback system 124 allows the hospital or other environment 100 implementing the lighting device 104 to quantitatively determine (and verify) that a sufficient level of inactivating dose was delivered over different time periods or at certain points in time (e.g., during a particular operation). This can be very advantageous in situations where, for example, a patient sues the hospital or other environment 100, alleging that she/he contracted an HAI while in the hospital or other environment 100.

As shown in Figures 4A-4C, the lighting device 104 can take the form of a light bulb or lamp 200. The lamp 200 includes an enclosed housing 204, an array 208 of light-emitting elements 212 coupled to (e.g., mounted or mounted on) a portion of the housing 204, a base 216 coupled to (e.g., integrally formed with) the housing 204, and an occupancy sensor 220 coupled to (e.g., disposed or arranged on) a portion of the housing 204. The occupancy sensor 220 is optimally positioned to detect motion within a predetermined range of the lamp 200 or within a predetermined distance (e.g., 50 feet) from the lamp within the environment 100. The lamp 200 can emit light in response to detection data obtained by the occupancy sensor 220, as discussed in more detail below.

As described above, the housing 204 is enclosed, thereby preventing moisture from entering the luminaire 200 and/or contaminating the internal components of the luminaire 200. More specifically, none of the interior surfaces of the housing 204 are exposed to the environment 100, preventing dangerous pathogens from residing on surfaces that are not reached by the light emitted by the lighting device 200. The housing 204 shown in Figures 4A to 4C is made or fabricated from aluminum or stainless steel and has a first end 224, a second end 228, an outwardly extending annular flange 230 formed at the second end 228, and an outer circumferential wall 232 extending between the first and second ends 224, 228. The outer circumferential wall 232 has a substantially conical shape, wherein the diameter of the circumferential wall 232 increases in a direction from the first end 224 to the second end 228, such that the diameter of the wall 232 at the second end 228 is larger than the diameter at the first end 224.

The housing 204 also includes a circular support surface 236 and an inner circumferential wall 240 surrounding the support surface 236. The support surface 236, at least facing downward in FIG. 4B , is configured to receive a portion or all of the array 208 of light-emitting elements 212. The inner circumferential wall 240, like the outer circumferential wall 232, has a substantially conical shape. The inner circumferential wall 240 is radially spaced from and within the outer circumferential wall 232 and extends between the flange 230 of the housing 204 and the support surface 236.

The housing 204 also includes a support member, which in this variation takes the form of a cylinder 244 disposed along a central axis 248 of the lamp 200. The cylinder 244 extends outwardly (downwardly when viewed in FIG. 4B ) from the support surface 236 and terminates at an end 250 positioned axially inward of the second end 228 (i.e., axially between the first and second ends 224, 228). A cavity 252 is formed or defined adjacent the second end 228 and between the flange 230, the inner circumferential wall 240, and the cylinder 244.

The array 208 of light emitting elements 212 is typically arranged on or within the enclosed housing 204. In this variation, the array 208 of light emitting elements 212 is arranged on an outer portion of the enclosed housing 204 that is exposed to the environment 100. More specifically, the light emitting elements 212 are arranged in the cavity 252, on the support surface 236 and around the post 244, as shown in Figures 4B and 4C. The light emitting elements 212 can be fixed in any known manner (e.g., using fasteners, adhesives, etc.). Depending on the specified application, such as depending on the health care environment 100, any number of light emitting elements 212 can be utilized. For example, for larger environments 100 and/or for environments 100 that are particularly prone to high levels of dangerous pathogens, more light emitting elements 212 can be used.

The light-emitting elements 212 include one or more first light-emitting elements 256 and one or more second light-emitting elements 260 arranged in many different configurations. The light-emitting elements 212 shown in Figures 4C and 4D include multiple groups 262, each group having one first light-emitting element 256 surrounded by three second light-emitting elements 260. However, in other embodiments, the light-emitting elements 212 can be arranged differently, for example, one or more of the groups 262 having light-emitting elements 256 and second light-emitting elements 260 arranged differently. In this variation, the light-emitting elements 256 are in the form of light-emitting diodes (LEDs) and are configured to collectively (i.e., jointly) emit at least 3,000 mW of a specific configuration of visible light, i.e., light having a wavelength in the range of about 380 nm to about 420 nm, and more particularly, light having a wavelength between 400 nm and 420 nm. In some cases, the light-emitting elements 256 can be configured to collectively emit at least 5,000 mW of a specific configuration of visible light, while in other cases, the light-emitting elements can be configured to collectively emit at least 10,500 mW of a specific configuration of visible light. Light-emitting element 260, at least in this variation, also takes the form of an LED, but is configured to emit visible light that supplements the visible light emitted by light-emitting element 256. Generally, the light emitted by light-emitting element 260 has a longer wavelength than the light emitted by light-emitting element 256. In many cases, some, if not all, of light-emitting elements 260 may emit light having a wavelength greater than 500 nm. For example, light-emitting element 260 may emit red, green, and blue light that, in combination, produces or forms white visible light. In many cases, the total light emitted by light-emitting element 256 has a higher luminous flux than the total light emitted by light-emitting element 260, but this need not always be the case.

In any case, the light emitting elements 256 and 260 are configured so that the total or combined light emitted by the array 208 is white, off-white, or a different color that is not aesthetically objectionable in the healthcare environment 100. Generally, the total or combined light has a color rendering index of 70 or greater, and more preferably 80 or greater or 90 or greater, and will have a color temperature in the range of 1500 degrees Kelvin to 7000 degrees Kelvin, preferably 2100 degrees Kelvin to 6000 degrees Kelvin, and more preferably 2700 degrees Kelvin to 5000 degrees Kelvin.

The base 216 is coupled proximate to the first end 224 of the housing 204 and projects outwardly from the first end. In this variation, the base 216 is a threaded base that is integrally formed with the housing 204 and is adapted to be screwed into a mating receptacle (not shown) disposed in a receiving structure in the healthcare environment 100. Depending on the healthcare environment 100, the mating receptacle may be disposed in a wall, ceiling, floor, housing, or some other structure. In any case, as is known in the art, the threaded base 216 may include one or more electrical contacts adapted to electrically connect to corresponding electrical contacts of the receptacle when the base 216 is coupled to the receptacle, thereby powering the light fixture 200.

It is generally desirable to screw the base 216 into a mating socket so that at least a portion of the housing 204 is embedded in a separate structure, thereby isolating that portion of the housing 204 from the external environment. Figures 5A and 5B illustrate such an embodiment, in which the luminaire 200 is sealingly disposed in a receiving structure 270 disposed (e.g., formed) in a ceiling, a house, or other structure in the environment 100. The receiving structure 270 has a substantially cylindrical base 272 and an outwardly extending flange 274 formed at an end 276 of the base 272. A seal (e.g., a gasket) 278 is disposed on the outwardly extending flange 274 of the receiving structure 270. When the base 216 of the light fixture 200 is screwed into a mating socket (not shown) disposed in the receiving structure 270, the housing 204 of the light fixture 200 is substantially completely disposed or embedded in the base 272 of the receiving structure 270, and the flange 230 of the light fixture 200 sealingly engages a seal 278 disposed on the flange 274 of the receiving structure 270. In this manner, the housing 204 is substantially sealed from the external environment 100.

4A and 4B , occupancy sensor 220—which can be a passive infrared motion sensor, a microwave motion sensor, an ultrasonic motion sensor, or another type of occupancy sensor—is disposed or provided on a downwardly facing portion of housing 204. In this variation, occupancy sensor 220 is provided on end 250 of cylinder 244, which allows occupancy sensor 220 to detect motion within environment 100 within a predetermined range of lighting fixture 200 or within a predetermined distance (e.g., 50 feet) from the lighting fixture. In some cases, occupancy sensor 220 can detect any motion within environment 100 (e.g., when environment 100 includes only one light fixture 200). As briefly discussed above, light fixture 200 can emit light in response to detection data obtained by occupancy sensor 220. More specifically, light fixture 200 can adjust the light output in response to detection data obtained by occupancy sensor 220. When, for example, the occupancy sensor 220 does not detect any motion within a predetermined range or distance, the light fixture 200 can be turned off or emit less light from the second light emitting element 260 because the healthcare environment 100 is not occupied (thus, the color of the light emitted is not important). In other words, the light fixture 200 can emit light only from the first light emitting element 256, thereby inactivating dangerous pathogens while using less power. Conversely, when the occupancy sensor 220 detects motion within a predetermined range or distance, the light fixture 200 can emit light from both the first light emitting element and the second light emitting element 256, 260, thereby ensuring that aesthetically unobtrusive light (e.g., white light) is provided to the occupied healthcare environment 100, and at the same time, the light fixture 200 continues to inactivate dangerous pathogens even when the environment 100 is occupied.

4A and 4B , the lamp or bulb 200 further includes an annular refractor 280. In this variation, the refractor 280 is a nano-repeating refractive film mounted to the inner circumferential wall 240 of the housing 204. The refractor 280 can be secured thereto via any known means (e.g., using a plurality of fasteners, using an adhesive, etc.). Thus arranged, the refractor 280 surrounds or encloses the first and second light-emitting elements 256, 260 so that the refractor 280 helps focus and evenly distribute light emitted from the lamp 200 toward the environment 100. If desired, the refractor 280 can be arranged differently or other types of refractors can be used instead to produce different controlled light distributions.

Although not described herein, it will be understood that one or more drivers (e.g., LED drivers), one or more other sensors (e.g., daylight sensors), one or more lenses, one or more reflectors, one or more boards (e.g., printed circuit boards, user interface boards), wiring, various control components (e.g., a local controller communicatively connected to the server 66), one or more communication modules (e.g., one or more antennas, one or more receivers, one or more transmitters), and/or other electrical components may be arranged or disposed within or adjacent to the enclosure 204. The communication modules may include one or more wireless communication modules and/or one or more wired communication modules. The one or more communication modules may thus facilitate wireless and/or wired communication between components of the bulb or luminaire 200 and the local controller, the server 66, and/or other control system components using any known communication protocol. More specifically, the one or more communication modules may facilitate the transmission of various data, such as occupancy or motion data, operational instructions (e.g., turn on, turn off, dim, etc.), between components of the bulb or luminaire 200 and the local controller, the server 66, other lighting devices 58, and/or other control system components. For example, data indicating when light is emitted from the light emitting elements 256, 260 may be monitored via such a communication module and transmitted to the server 66. For another example, data indicating how much light is emitted from the light emitting elements 256, 260 within a predetermined time period (e.g., during a particular surgical procedure) may be monitored via such a communication module and transmitted to the server 66.

In other variations, the bulb or light fixture 200 can be configured differently. Specifically, the housing 204 can have a different size, shape, and/or be made of one or more materials other than or in addition to aluminum or stainless steel. For example, the housing 204 can have a rectangular, square, triangular, irregular, or other suitable shape. In one variation, the housing 204 can include the post 244, and/or the post 244 can have a shape and/or size different from the cylindrical post 244 shown in Figures 4A and 4B.

In addition, the array 208 of light-emitting elements 212 can vary. In some variations, the array 208 (or portions thereof) can be arranged in or on different portions of the housing 204. In some variations, the array 208 of light-emitting elements 212 can include only the first light-emitting element 256, as described above, which is configured to emit a specific configuration of spectrum visible light at a sufficiently high power level. In these variations, one or more of the light-emitting elements 256 can be covered or coated with a phosphor, a matrix infused with a phosphor, and/or one or more other materials and/or media to produce light having a wavelength greater than the specific configuration of narrow spectrum visible light, so that the total light or combined light emitted by the array 208 is white, off-white, or a different color that is not aesthetically objectionable in the healthcare environment 100. 6A and 6B depict one such variation in which the light-emitting elements 212 include a plurality of groups 284 of four light-emitting elements 256, three of which 256A, 256B, and 256C are covered or coated with a phosphor, and one of which 256D is uncovered (i.e., not coated with phosphor). In the illustrated variation, the three light-emitting elements 256A, 256B, and 256C are covered or coated with a blue, red, and green phosphor, respectively, such that the total or combined light emitted by each group 284 (and therefore the array 208) is white, off-white, or a different color that is aesthetically unobjectionable in the healthcare environment 100. It will be understood that in other variations, more or fewer of the light-emitting elements 256 can be covered with phosphor, the light-emitting elements 256 can be covered with different colors of phosphor, and/or the light-emitting elements 256 can be arranged differently relative to each other (i.e., the groups 284 can vary). In further variations, the array 208 may include additional lighting elements (even for larger room doses) that are configured to turn on only when no motion is detected in the environment 100, such as LEDs configured to emit a specific configuration of visible light at a sufficiently high power level. Finally, it is understood that instead of LEDs, the first and/or second lighting elements 256, 260 may take the form of fluorescent, incandescent, plasma, or other lighting elements.

FIG7 illustrates another variation of the lighting device 104. As shown in FIG7 , the lighting device 104 can take the form of a light bulb or lamp 300. The lamp 300 is substantially similar to the lamp 200, with common reference numerals being used to refer to common components. However, unlike the lamp 200, the lamp 300 includes a heat sink 302 formed on an outer surface of the lamp 300 and configured to dissipate heat generated by the lamp 300, and more particularly, by the light-emitting elements 212. In some cases, the heat sink 302 can be coupled (e.g., mounted, attached) to or around a portion of the outer circumferential wall 232, while in other cases, the heat sink 302 can be integrally formed with the housing 204 (in which case, the heat sink 302 can replace a portion or all of the wall 232).

FIG8 illustrates yet another variation of the lighting device 104. As shown in FIG7 , the lighting device 104 can take the form of a light bulb or lamp 400. The lamp 400 includes an enclosed housing 404 that is different from the housing 204 of the lamps 200 and 300. In this variation, the enclosed housing 404 is made or manufactured from glass or plastic and is shaped like the housing of a conventional incandescent light bulb. The lamp 400 also includes a base 416 that is similar to the base 216 described above. However, unlike a conventional incandescent light bulb, the lamp 400 also includes a light-emitting element 212 that is disposed within the enclosed housing 404 and, as described above, is configured to provide a narrow spectrum of visible light of a specific configuration that is sufficient to effectively inactivate dangerous pathogens at a sufficiently high power level while providing a non-objectionable quality light output.

9A-9D illustrate another variation of the lighting device 104 in the form of a luminaire 500. Luminaire 500 includes a housing or chassis 504, a plurality of light-emitting elements 512 coupled to (e.g., mounted or seated on) a portion of the housing 504, a lens 514 configured to effectively diffuse light emitted by the light-emitting elements 512, a pair of support arms 516 coupled to (e.g., integrally formed with) the housing 504, and a control device in the form of a local controller 520, similar to the controller 120 described above. It will be appreciated that luminaire 500 also includes an occupancy sensor, a daylight sensor, a communication module, and a dosage feedback system; however, these components are identical to the motion sensor 108, daylight sensor 112, communication module 116, and dosage feedback system 124, respectively, described above, and therefore, for the sake of brevity, are not shown in FIG. 9A-9C and will not be described in detail below. Luminaire 500 may also include any of the devices described above in connection with the lighting device 104 for maintaining junction temperature.

In this variation, housing 504 is fabricated or manufactured from steel (e.g., 18-gauge welded cold-rolled steel) and has a substantially rectangular flange 528 surrounding a curved interior support surface 532, which faces downward, at least in FIG. 9B . Rectangular flange 528 and curved interior support surface 532 together define a cavity 536 sized to receive lens 514, which in this embodiment is a Frost DR Acrylic lens manufactured by Kenall Manufacturing. Support arms 516 are coupled to an exterior portion of housing 504 proximate flange 528, with one support arm 516 coupled at or near a first end 544 of housing 504 and the other support arm 516 coupled at or near a second end 546 of housing 504, opposite first end 536. Thus, support arms 516 are arranged to facilitate mounting luminaire 500 within a ceiling, such as environment 100.

The light emitting elements 512 are typically arranged on or within the housing 504. In this variation, the light emitting elements 512 are arranged in a sealed or enclosed light mixing cavity 550 defined by the housing 504 and the lens 540. The light emitting elements 512 can be secured therein in any known manner (e.g., using fasteners, adhesives, etc.). In this variation, the light emitting elements 512 include a plurality of first light emitting elements in the form of a plurality of first LEDs 556 and a plurality of second light emitting elements in the form of a plurality of second LEDs 560. The light emitting elements 512 can be arranged on the first and second LED modules 554, 558 in the manner shown in FIG9C , wherein the second LEDs 560 are grouped together into various rows and columns and the first LEDs 556 are arranged between these rows and columns, or they can be arranged in a different manner. In one embodiment, in order to make the ratio of first LEDs 556 to second LEDs 560 equal to 1:6, ninety-six (96) first LEDs 556 and five hundred and seventy-six (576) second LEDs 560 are used. In other embodiments, more or fewer first and second LEDs 556, 560 may be employed, with a different ratio of first LEDs 556 to second LEDs 560. For example, the ratio of first LEDs 556 to second LEDs 560 may be equal to 1:3, 1:2, 1:1, or some other ratio, depending on the power capabilities of the first and second LEDs 556, 560.

As with the light emitting element 256, the first LEDs 556 are configured to provide (e.g., emit) a specific configuration of visible light, i.e., light having a wavelength within a range between about 380 nm and about 420 nm, and more particularly, light having a wavelength within a range between 400 nm and 420 nm, wherein the combination or sum of the first LEDs 556 is configured to provide or emit (e.g., emit) a sufficiently high level of the specific configuration of visible light to inactivate pathogens surrounding the luminaire 500. As described above, the first LEDs 556 may collectively (e.g., when concentrated) emit at least 3,000 mW of the specific configuration of visible light, such as 3,000 mW, 4,000 mW, 5,000 mW, or some other level of visible light above 3,000 mW. The lowest overall irradiance of visible light for a particular configuration emitted or otherwise provided by all LEDs 556—at least in this embodiment, as measured from any exposed surface or unobstructed point in environment 100 1.5 m from any point on any outermost light-emitting surface 562 of luminaire 504—can be equal to 0.01 mW/cm , ^0.02 mW/cm , ^0.05 mW/cm , ^0.1 mW/ ^cm , 0.15 mW/cm , 0.20 mW/ ^cm , 0.25 mW/ ^cm , ^0.30 mW/ ^cm , or some other value greater than 0.01 mW/ ^cm . In other embodiments, the lowest overall irradiance of visible light for a particular configuration can be measured from a different distance from any outermost light-emitting surface 562, from the lowest point, or from any other unobstructed or exposed surface in environment 100. Like the lighting element 260, the second LED 560 is configured to emit visible light, but the light emitted by the second LED 560 has a longer wavelength than the light emitted by the one or more first LEDs 556. The light emitted by the second LED 560 typically has a wavelength greater than 500 nm, but this is not necessarily the case.

In any case, the light emitted by the second LED 560 supplements the visible light emitted by the one or more first LEDs 556, such that the combined or mixed light output formed in the mixing chamber 550 is white light having the aforementioned properties (e.g., white light having a CRI of greater than 80, a color temperature in the range of 2100°C to 6000°C, and/or having (u′, v′) coordinates on the 1976 CIE chromaticity diagram located on a curve between 0.035 Duv below and 0.035 above the Planckian locus defined by the ANSI C78.377-2015 color standard). Thus, as shown, for example, in FIG. 9E , the combined or mixed light output by the luminaire 500 is aesthetically pleasing to humans.

9D , the lighting device 504 further includes a first LED driver 564 and a second LED driver 568, each electrically connected to the controller 520 and powered by external power (e.g., AC power) received from an external power source (not shown). The first LED driver 564 is configured to provide power to the first LED 556 in response to instructions or commands received from the controller 520, while the second LED driver 568 is configured to provide power to the second LED 560 in response to instructions or commands received from the controller. In other embodiments, the lighting device 564 may include more or fewer LED drivers. For example, the lighting device 564 may include only one LED driver configured to provide power to the first LED 556 and the second LED 560, or may include multiple LED drivers configured to provide power to the first LED 556 and multiple LED drivers configured to provide power to the second LED 560.

9D , the controller 520 can receive a dimming setting 572 and/or a mode control setting 576 received from a user of the lighting device 504 (e.g., via an input from a dimming switch electrically connected to the light fixture 500) and/or a central controller via, for example, the server 66. The dimming setting 572 is a 0-10V control signal that specifies a desired dimming or dimming level for the lighting device, where the desired dimming or dimming level is a ratio between a desired combined light output of the first and second LEDs 556, 560 and a maximum combined light output of the first and second LEDs 556, 560 (and corresponds to the mixed or combined output described above). An input of 0V typically corresponds to a desired dimming level of 100% (i.e., no power is supplied to the first LED 556 or the second LED 560), an input of 5V typically corresponds to a desired dimming level of 50%, and an input of 10V typically corresponds to a desired dimming level of 0% (i.e., full power is supplied to the first and second LEDs 556, 560), but this need not always be the case. The mode control setting 576 is a control signal that specifies the desired operating mode of the lighting device 504. The mode control setting 576 may, for example, specify that the lighting device 504 be in a first mode (e.g., inspection mode, disinfection mode, hybrid mode) in which full power is supplied to the first and second LEDs 556, 560, or in a second mode (e.g., night mode) in which power is supplied to the second LED 560 and no power is supplied to the first LED 556 (or supplied at a lower level). Other modes and/or modes corresponding to different power settings or levels may be utilized.

In operation, the luminaire 500 provides or outputs (e.g., emits) light based on or in response to commands or instructions from the local controller 520. More specifically, based on or in response to commands or instructions received from the local controller 520 to cause the first LED 556 and/or the second LED 560 to provide or output (e.g., emit) a desired level of light, the first LED driver 564 and/or the second LED driver 568 supplies power to the first LED 556 and/or the second LED 560 to achieve this effect. These commands or instructions may be generated based on or in response to receiving the dimming setting 572, receiving the mode control setting 576, occupancy data obtained by the occupancy sensor and/or daylight data obtained by the daylight sensor, and/or based on or in response to commands or instructions received from the server 66 and/or the client device 70. Thus, the luminaire 500, and more particularly the first LED 556 and/or the second LED 560, can provide (e.g., emit) light in response to occupancy data obtained by the occupancy sensor, daylight data obtained by the daylight sensor, and/or other commands or instructions (e.g., time settings, dimming settings, mode control settings).

For example, in response to data indicating that the environment 100 is occupied, data indicating that there is more than a predetermined amount of natural light in the environment 100 (i.e., it is daytime), and/or various commands and instructions, the luminaire 500 can emit light from the first LED 556 and the second LED 560 to produce a mixed or combined white visible light output as described above. In turn, the luminaire 500 produces visible white light that effectively inactivates dangerous pathogens in the environment 100, while at the same time illuminating the environment 100 in a safe and non-offensive manner (e.g., because the environment 100 is occupied, it is daytime, and/or for other reasons).

However, in response to data indicating that the environment 100 is unoccupied or has been unoccupied for a predetermined amount of time (e.g., 30 minutes, 60 minutes), the luminaire 500 can reduce the power of the second LED 560 so that most of the output light comes from the first LED 556, or turn off the second LED 560 (because the environment 100 is unoccupied and therefore no longer needs to produce a visually appealing mixed output) so that light is emitted only from the first LED 556, as shown in FIG9F . Simultaneously, the luminaire 500 can increase the power or intensity of the first LED 556 and, in some cases, can activate one or more third LEDs, not shown, but which, like the LED 556, are also configured to emit a sufficiently high level of a particular configuration of visible light, i.e., light having a wavelength in the range between about 380 nm and about 420 nm, and more particularly, light having a wavelength between 400 nm and 420 nm. In this way, the deactivation effect of the luminaire 500 may be improved (without detracting from the visual appeal of the luminaire 500 when the environment 100 is unoccupied) and at the same time, the energy consumption of the luminaire 500 may be reduced or at least maintained (due to the first LED 556 being reduced or turned off).

In some cases, in response to data indicating that the environment 100 is unoccupied or has been unoccupied for a period of time shorter than a predetermined amount of time (e.g., 30 minutes), the luminaire 500 may provide or output a combined or mixed light output of the above (first and second LEDs 556, 560). This provides a fail-safe mode that ensures that the environment 100 is indeed idle before turning off or reducing the second LED 560.

For data indicating that there is more than a predetermined amount of natural light in the environment 100 or that the natural light in the environment 100 is lower than the predetermined amount (i.e., at night, making the environment 100 less likely to be occupied), the luminaire 500 may respond in a similar or different manner such that light from the second LED 560 is not required. If desired, the luminaire 500 may respond in such a manner only in response to data indicating that the environment 100 is not occupied or that it is nighttime. Alternatively, the luminaire 500 may respond in such a manner only in response to a time setting (e.g., past 6:30 P.M.) and/or other commands or instructions.

The light fixture 500, and more particularly the first LED 556 and the second LED 560, can also be controlled in response to settings, such as a dimming setting 572 and a mode control setting 576 received by the controller 520. In response to receiving the dimming setting 572 or the mode control setting 576, the controller 520 causes the first and second LED drivers 564 and 568 to power (or not power) the first and second LEDs 556 and 560, respectively, in accordance with the received settings. More specifically, when the controller 520 receives the dimming setting 572 or the mode control setting 576, the controller 520 instructs the first LED driver 564 to power (or not power) the first LED 556 and instructs the second LED driver 568 to power (or not power) the second LED 560, respectively, via a first LED control signal 580, and in accordance with a second LED control signal 584, in accordance with a desired dimming level specified by the dimming setting 572 or a desired operating mode specified by the mode control setting 576.

FIG9G illustrates how the controller 520 can control the first and second LED drivers 564 and 568 in response to various dimming settings 572 specifying various dimming levels (e.g., 0%, 25%, 50%, 75%, and 100%). Generally speaking, the controller 520 causes the first and second LED drivers 564 and 568 to increase the total light output by the first and second LEDs 556 and 560 in response to decreasing dimming levels, thereby increasing the color temperature of the total light output, and causes the first and second LED drivers 564 and 568 to decrease the total light output by the first and second LEDs 556 and 560 in response to increasing dimming levels, thereby decreasing the color temperature of the total light output. However, as shown in FIG9G , the controller 520 controls the first LED 556 (via the first LED driver 564) in a different manner than it controls the second LED 560 (via the second LED driver 568). In other words, at different dimming levels, there is a nonlinear relationship between the amount of light emitted by the first LED 556 and the amount of light emitted by the second LED 560. This relationship is illustrated by the fact that a first curve 588, which represents the total power supplied to the first and second LEDs 556, 560, respectively, by the first and second LED drivers 564, 568 at different dimming levels, is not parallel to a second curve 592, which represents the power supplied to the first LED 556 at the same dimming level. For example, (i) when the dimming setting 572 specifies a dimming level of 0% (i.e., no dimming), such that the luminaire 500 is operated at full (100%) power, approximately 50% of the total power is supplied to the first LED 556, (ii) when the dimming setting 572 specifies a dimming level of 50%, such that the luminaire 500 is operated at half (50%) power, less than 50% of the total power is supplied to the first LED 556, and (iii) when the dimming setting 572 specifies a dimming level greater than 75% but less than 100%, such that the luminaire 500 is operated at less than 25% power, no power is supplied to the first LED 556. Thus, the first LED 556 is completely turned off before the second LED 560 is completely turned off. In this way, even when the lamp 500 is dimmed, and particularly when dimmed to very high levels (e.g., 80%, 85%, 90%, 95%), the light output by the lamp 500 remains unobtrusive and aesthetically pleasing.

10A-10D illustrate another variation of the lighting device 104 in the form of a luminaire 600. Luminaire 600 is similar to luminaire 500 in that it includes a housing or chassis 604 (having a flange 628) and a lens 614 configured to diffuse the light emitted by the luminaire in an effective manner, as well as components such as a local controller 618, an occupancy sensor, a communication module, and a dosage feedback system, which are identical to the controller 120, sensor 108, module 116, and dosage feedback system 124 described above, respectively; therefore, for the sake of brevity, these components will not be described in further detail. Luminaire 600 may also include any of the means for maintaining the junction temperature described above with respect to lighting device 104. However, luminaire 600 includes a plurality of light-emitting elements 612, which are different from the plurality of light-emitting elements 512 of luminaire 500. Although, like elements 512, light-emitting elements 612 are arranged on an LED module 654 within a sealed or enclosed light-mixing cavity defined by a housing 604 and a lens 614, as shown in Figures 10B and 10C, each light-emitting element 612 takes the form of a light-emitting diode ("LED") 656 and a light-converting element 657 associated with the LED and configured to convert a portion of the light emitted by the LED 656, as shown in Figure 10D. In this variation, each LED module 654 includes seventy-six (76) light-emitting elements 612, but in other variations, more or fewer light-emitting elements 612 may be employed (and/or additional LEDs 656 may be employed without the light-converting element 657). While in this variation, the light conversion element 657—which may be, for example, a phosphor element such as a phosphor or a matrix infused with a phosphor—covers or coats the LED 656, in other variations, the light conversion element 657 may be remotely positioned relative to the LED 656 (e.g., a remote phosphor element).

In operation, the LEDs 656 of the light emitting element 612 emit disinfecting light (e.g., light having a wavelength between 400 nm and 420 nm) that, when combined or concentrated, produces a power level sufficient to inactivate pathogens. As described above, the LEDs 656 can be combined to emit at least 3,000 mW of disinfecting light, such as 3,000 mW, 4,000 mW, 5,000 mW, or some other level of visible light above 3,000 mW. At least a first portion or component 700 (and in FIG. 10D , multiple components 700) of the disinfecting light emitted by each LED 656 travels or passes through the corresponding light conversion element 657 without change, while at least a second portion or component 704 (and in FIG. 10D , multiple components 704) of the disinfecting light emitted by each LED 656 is converted by the corresponding light conversion element 657 to light having a wavelength greater than 420 nm. In many cases, the second portion or component 704 of the light is converted to yellow light, i.e., light having a wavelength between 570 nm and 590 nm. In other words, each light-emitting element 612 is configured to provide light having at least a first component provided by the corresponding LED 656 having a wavelength between 400 nm and 420 nm, and at least a second component of the light provided by the corresponding light-converting element 657 having a wavelength greater than 420 nm. As also described above, the first component of light provided will have a minimum overall irradiance, which, at least in this embodiment, is measured from any exposed surface or unobstructed point in the environment 100 at a distance of 1.5 m from any point on any outermost light emitting surface 662 of the lighting device 504, and is equal to 0.01 mW/cm ² , 0.02 mW/cm 2 , 0.05 mW/cm ² , 0.1 mW/cm ² , 0.15 mW/cm ² , 0.20 mW/cm ² , 0.25 ^{mW/cm 2 , 0.30 mW/cm 2 , or} some other value greater than 0.01 mW/cm ² . In other embodiments, the minimum overall irradiance may be measured from a different distance from any point on any outermost light emitting surface 662, from the lowest point, or from some other exposed surface or point in the environment 100.

At the same time, the light provided or output by the luminaire 600, and more particularly by each light-emitting element 612, is white light having the properties described above, such that the light provided is aesthetically pleasing or at least non-objectionable to humans. This is because the light provided by the light conversion element 657, i.e., the second component, supplements the disinfecting light, i.e., the first component, emitted by the LED 656 and passing through the light conversion element 657 without change.

As with luminaire 500, luminaire 600 can provide or output light based on or in response to commands or instructions from local controller 618. These commands or instructions can be generated based on or in response to occupancy data obtained by an occupancy sensor and/or daylight data obtained by a daylight sensor, and/or based on or in response to commands or instructions received from a user of luminaire 600 (e.g., via client device 70) and/or from server 66. Thus, luminaire 600 can provide light in response to occupancy data obtained by an occupancy sensor, daylight data obtained by a daylight sensor, and/or other commands or instructions (e.g., time settings).

FIG11A illustrates one embodiment of a distribution of radiant power output by a lighting device 1100, which may take the form of any of the lighting devices 104, 200, 500, and 600 described herein. As shown in FIG11A , the radiant power along a central axis 1104 of the light distribution of lighting device 100 is at a maximum value, while the radiant power along a line 1108 oriented at an angle θ with respect to central axis 1104 is equal to 50% of the maximum radiant power value, provided that the radiant power along central axis 1104 and the radiant power along line 1108 are measured at equal distances from lighting device 1100. In this variation, line 1108 is oriented at an angle θ of 20 or 30 degrees with respect to central axis 1104, but may be oriented at a different angle θ in other variations.

It will be appreciated that a lighting device, such as one of the lighting devices 104, 200, 500, 600, 1100 described herein, can distribute light in many different ways within or throughout the environment 100, depending on the given application. The lighting device can, for example, utilize a Lambertian distribution 1120, an asymmetric distribution 1140, a spotlight-like distribution with cutouts 1160, or a direct-indirect distribution 1180, as shown in Figures 11B-11E, respectively.

FIG11B shows a Lambertian distribution diagram 1120 in the form of a two-dimensional pole figure, depicting the magnitude M of the intensity of light output from the lighting device as a function of a vertical angle α relative to the horizontal. As shown in FIG11B , Lambertian distribution diagram 1120 includes a first light distribution 1124 measured along a vertical plane through horizontal angles of 0 to 180 degrees, a second light distribution 1128 measured along a vertical plane through horizontal angles of 90 to 270 degrees, and a third light distribution 1132 measured along a vertical plane through horizontal angles of 180 to 0 degrees. As shown in each of the first, second, and third light distributions 1124, 1128, and 1132, the magnitude M of the light intensity is at a maximum (5240 candelas in this embodiment) when the vertical angle α is equal to 0 degrees (i.e., the nadir), resulting in a main beam angle corresponding to the vertical angle with the highest magnitude being equal to 0 degrees. The magnitude M then decreases as the vertical angle α moves from 0 degrees to 90 degrees.

FIG11C also illustrates an asymmetric distribution graph 1140, also in the form of a two-dimensional pole figure, depicting the magnitude M of the intensity of light output from the lighting device as a function of a vertical angle α from the horizontal. As shown in FIG11C , asymmetric distribution graph 1140 includes a first light distribution 1144 measured along a vertical plane at horizontal angles between 0 and 180 degrees, and a second light distribution 1148 measured along the vertical plane at horizontal angles between 90 and 270 degrees. As illustrated by first and second light distributions 1144 and 1148, light is asymmetrically distributed on one side of the lighting device, with the magnitude M of the light intensity reaching a maximum value (2307 candelas in this embodiment) at a vertical angle α of 25 degrees. This distribution can be utilized, for example, in an environment 100 featuring an operating table to direct the main beam of light from the lighting device toward the operating table.

FIG11D also illustrates a two-dimensional pole figure depicting the intensity M of light output from the recessed lighting fixture as a function of a vertical angle α relative to the horizontal. As shown in FIG11D , this distribution graph 1160 includes a first light distribution 1164 measured along a vertical plane through horizontal angles between 0 and 180 degrees, a second light distribution 1168 measured along a vertical plane through horizontal angles between 90 and 270 degrees, and a third light distribution 1172 measured along a horizontal cone through a vertical angle α of 20 degrees. As shown in the first, second, and third light distributions 1164, 1168, and 1172, the intensity of the light reaches a maximum (in this embodiment, 2586 candelas) at a horizontal angle of 60 degrees and a vertical angle α of 20 degrees, with very low light intensity occurring above 45 degrees (i.e., the light is off). Thus, the main beam angle corresponding to the highest vertical angle α is equal to 20 degrees, making this distribution suitable for applications that require an off-center but symmetrical distribution. This type of distribution generally allows for larger spacing between adjacent luminaires while still providing a relatively uniform projection of light on the ground.

FIG11E also illustrates a direct-indirect distribution graph 1180, which takes the form of a two-dimensional pole figure and depicts the magnitude M of the intensity of light output from the lighting device as a function of a vertical angle α from the horizontal. As shown in FIG11E , distribution graph 1180 includes a first light distribution 1184 measured along a vertical plane through horizontal angles between 90 and 270 degrees, and a second light distribution 1188 measured along a vertical plane through horizontal angles between 180 and 0 degrees. As shown in first and second light distributions 1184 and 1168, the magnitude M of the light intensity reaches a maximum value (1398 candelas in this embodiment) when the horizontal angle is 90 degrees and the vertical angle α is 117.5 degrees. A majority (e.g., approximately 80%) of the light is directed upward, as indicated by the greater light intensity at vertical angles α between 90 and 270 degrees. Therefore, the main beam angle corresponding to the highest magnitude vertical angle α is equal to 117.5 degrees, making this distribution suitable for applications such as lighting fixtures being hung from a ceiling and providing light to the environment using the ceiling, which in turn provides low brightness light to the environment.

11F through 11I each depict a graph detailing the luminous flux (measured in lumens) for a Lambertian distribution, an asymmetric distribution, a spotlight distribution with a cutout portion, and a direct-indirect distribution 1120, 1140, 1160, and 1180, respectively. More specifically, each graph details the summary of the luminous intensity (i.e., luminous flux) within the solid angle of the corresponding distribution 1120, 1140, 1160, and 1180 for various regions at a vertical angle α.

FIG12 depicts a flow chart of a method 1200 for providing a sufficient dose of light over a period of time (e.g., 24 hours) to inactivate dangerous pathogens (e.g., MRSA bacteria) within an entire three-dimensional space (e.g., environment 100). Method 1200 is implemented in the order shown, but may also be implemented according to or in accordance with many different orders. Method 1200 may include additional, fewer, or different actions. For example, the first, second, third, and/or fourth data received in action 1205 may be received at different times before action 1220, and receiving data at different times constitutes different actions. For another example, actions 1205, 1210, and 1215 may be repeated many times before performing action 1220.

Method 1200 begins when data associated with a stereoscopic space is received (act 1205). The data may include: (i) first data associated with a desired illumination level for the stereoscopic space, (ii) second data indicating an estimated occupancy of the stereoscopic space over a predetermined time period, (iii) third data indicating the length, width, and/or height of the stereoscopic space (one or more of the length, width, and/or height may be default values and therefore need not be provided), and (iv) fourth data indicating a preferred CCT (correlated color temperature) for the stereoscopic space. Although in this variation the first, second, third, and fourth data are described as being received simultaneously, such data may be received at different times. The desired illumination level will vary depending on the application and the size of the stereoscopic space, but may be, for example, 40-60 fc, 100-125 fc, 200-300 fc, or some other value or range of values. The estimated occupancy of the stereoscopic space over the predetermined time period is typically related to the amount of time per day that the stereoscopic space is occupied. Like the desired illumination level, the amount of time occupied will vary depending on the application, but may be 4 hours, 6 hours, 8 hours, 12 hours, or some other period. The preferred CCT of the volumetric space will also vary depending on the given application, but may be, for example, in the range of between about 1500K and 7000K, more particularly between about 1800K and 5000K.

Method 1200 includes determining an arrangement of one or more lamps to be installed in a three-dimensional space (act 1210). Although in the illustrated method, this determination is based on first data, this determination can be made based on a combination of first data, second data, third data, and/or fourth data. The arrangement of one or more lamps typically includes one or more of any of the lamps described herein, such as lamp 200, lamp 500, lamp 600, and/or one or more other lamps (e.g., one or more lamps configured to emit only disinfecting light). Thus, the arrangement of one or more lamps is configured to at least partially provide or output (e.g., emit) disinfecting light having a wavelength between 380 nm and 420 nm, more particularly, a wavelength between 400 nm and 420 nm. In some cases, the one or more lamps can also be configured to at least partially provide light having a wavelength greater than 420 nm, so that the combined or mixed light output of the lamps is more aesthetically pleasing or less objectionable than the light output of other situations. The arrangement of one or more lamps may further include means for directing the disinfecting light, such as, for example, one or more reflectors, one or more diffusers, and one or more lenses positioned within or outside the lamp. The arrangement of one or more lamps may optionally include means for managing the heat generated by the one or more lamps so that heat-sensitive components in the one or more lamps can be protected. The means for managing heat may, for example, take the form of one or more heat sinks and/or may involve the use of a switching circuit that, when a lamp utilizing two light-emitting devices is employed, prevents the two circuits of the light-emitting devices from being energized simultaneously during use. In some cases, a thermal fuse may be added to prevent the lamp from overheating.

Method 1200 also includes determining a total radiant power to be applied to the volumetric space via the one or more luminaires so as to produce a desired power density at any exposed surface (i.e., unobstructed surface) within the volumetric space within a time period (act 1215). Although this determination is based on the second and third data in the illustrated method, this determination may be based on a combination of the first, second, third, and/or fourth data. As described above, the desired power density may be or include a minimum overall irradiance equal to 0.01 mW/ ^cm2 , 0.02 mW/ ^cm2 , 0.05 mW/ ^cm2 , 0.1 mW/ ^cm2 , 0.15 mW/ ^cm2 , 0.20 mW/ ^cm2 , 0.25 mW/ ^cm2 , 0.30 mW/ ^cm2 , or some other value greater than 0.01 mW/ ^cm2 . The minimum overall irradiance can be measured from any unobstructed point in the three-dimensional space, at a distance of 1.5 meters from any outermost luminous surface of the lighting device, at the lowest point, or at some other point or surface in the three-dimensional space. In this way, dangerous pathogens in the three-dimensional space can be effectively inactivated.

In one embodiment, the total radiant power to be applied to the volumetric space may be determined according to the following formula: Total radiant power = (minimum overall irradiance (mW/cm ² ) * duration (fraction of a day)) / volume of the volumetric space (ft ³ ), where duration represents the amount of time per day that the volumetric space is occupied, and where the volume of the volumetric space is calculated by multiplying the length, height, and width of the volumetric space.

In some cases, such as when an arrangement of one or more luminaires includes one or more luminaires such as luminaire 500 that can operate in different modes, the total radiated power can be calculated for each mode and then summed to produce the total radiated power to be applied to the stereoscopic space.

Once the total radiant power to be applied to the volume is determined, the determined total radiant power can be compared to other applications (i.e., other volumes) where actual disinfection levels have been measured to verify that the determined total radiant power for the volume is sufficient to inactivate dangerous pathogens.

The method 1200 then includes installing the determined lighting fixtures in the three-dimensional space (action 1220), which can be performed in any known manner so that the determined total radiant power can be applied to the three-dimensional space via the one or more lamps. The method 1200 optionally includes an action of applying the determined total radiant power to the three-dimensional space via the one or more lamps (action 1225). Applying the determined total radiant power without using any photosensitizer or reactant will produce a desired power density in the three-dimensional space within the time period. In turn, within the specified time period, the specifically arranged and configured lamps inactivate dangerous pathogens in the three-dimensional space.

In some cases, action 1225 may also involve controlling the one or more lamps, which may be performed via one or more controllers (e.g., controller 120, controller 520) communicatively connected to the lamps. More specifically, the wavelength, intensity, bandwidth, or some other parameter of the disinfecting light (i.e., light having a wavelength between 400 nm and 420 nm) may be controlled or adjusted. This control or adjustment may be performed automatically in response to a control signal received from a central controller remotely located relative to the one or more lamps and/or in response to input received from a user or operator of the lamp (e.g., via one of the client devices 70), such as when the one or more controllers detect, via one or more sensors, a deviation in the wavelength, intensity, bandwidth, or some other parameter of the disinfecting light. In one embodiment, the one or more lamps may be controlled in response to new or modified first, second, third, and/or fourth data received and/or detected (e.g., via an image controller). In any case, this control or adjustment helps maintain a desired power density so that the one or more lamps continue to effectively inactivate dangerous pathogens throughout the volume.

It will be understood that the size of the stereoscopic space can vary depending on the specified application. For example, the stereoscopic space can have a volume up to and including 25,000 ft ³ (707.92 ^{m 3} ). In some cases, the stereoscopic space can be defined or bounded in part by the plane of the one or more luminaires and the floor plane of the stereoscopic space. For example, the stereoscopic space can be defined in part by the area extending between 0.5 m below the plane of the one or more luminaires and 24 inches (60.96 cm) above the floor plane of the stereoscopic space, or the area extending between 1.5 m below the plane of the one or more luminaires and 24 inches (60.96 cm) above the floor plane of the stereoscopic space. Alternatively, the stereoscopic space can be defined by areas at different distances from the plane of the one or more luminaires and/or the floor plane of the stereoscopic space.

Finally, it will be understood that actions 1205, 1210, 1215, 1220, and 1225 of method 1200 can be performed by a server 66 associated with the stereoscopic space, one of the client devices 70, some other machine or device, a person such as a user, technician, administrator, or operator, or a combination thereof.

Figure 13 shows an exemplary control device 1325, via which some of the functions discussed herein can be implemented. In some variations, the control device 1325 can be the server 66 discussed relative to Figure 1, the local controller 120 discussed relative to Figure 2, the dosage feedback system 124 discussed relative to Figure 2, the local controller 520 discussed relative to Figure 9 D, the local controller 618, or any other control component (such as a controller) described herein. Typically, the control device 1325 is a dedicated machine, device, controller, etc., including any combination of hardware and software components.

The control device 1325 may include a processor 1379 or other similar type of controller module or microcontroller, and a memory 1395. The memory 1395 may store an operating system 1397 capable of facilitating the functionality described herein. The processor 1379 may interface with the memory 1395 to execute the operating system 1397 and a set of applications 1383. The set of applications 1383 (which the memory 1395 may also store) may include a lighting settings application 1381 configured to generate commands or instructions for implementing various lighting settings and transmit these commands/instructions to a set of lighting devices. It will be appreciated that the set of applications 1383 may include one or more other applications 1382.

Typically, memory 1395 may include one or more forms of volatile and/or non-volatile fixed memory and/or removable memory, such as read-only memory (ROM), electronically programmable read-only memory (EPROM), random access memory (RAM), erasable electronically programmable read-only memory (EEPROM) and/or other hard drives, flash memory, MicroSD cards, and others.

The control device 1325 may also include a communication module 1393 configured to interface with one or more external ports 1385 to transmit data via one or more networks 1316 (e.g., which may take the form of one or more of the networks 74). For example, the communication module 1393 may utilize the external ports 1385 to establish a WLAN to connect the control device 1325 to a set of lighting devices and/or a set of bridging devices. According to some embodiments, the communication module 1393 may include one or more transceivers that operate in accordance with IEEE standards, 3GPP standards, or other standards and are configured to receive and transmit data via the one or more external ports 1385. More particularly, the communication module 1393 may include one or more wireless or wired WAN, PAN, and/or LAN transceivers configured to connect the control device 1325 to a WAN, PAN, and/or LAN.

The control device 1325 may also include a user interface 1387 configured to present information to a user and/or receive input from a user. As shown in FIG13 , the user interface 1387 includes a display screen 1391 and I/O components 1389 (e.g., capacitive or resistive touch input panels, keys, buttons, lights, LEDs, cursor control devices, haptic devices, and others).

Generally, a computer program product according to an embodiment includes a computer-usable storage medium (e.g., standard random access memory (RAM), a compact disc, a universal serial bus (USB) disk, etc.) having computer-readable program code embodied therein, wherein the computer-readable program code is adapted to be executed by a processor 1379 (e.g., in cooperation with an operating system 1397) to facilitate the functionality described herein. In this regard, the program code may be implemented in any desired language and may be implemented as machine code, assembly code, byte code, human-readable source code, etc. (e.g., via C, C++, Java, Actionscript, Objective-C, JavaScript, CSS, XML, and/or other implementations).

Throughout the specification, plural instances may be implemented as components, operations, or structures described as single instances. Although the individual operations of one or more methods are shown and described as separate operations, one or more of the individual operations may be performed simultaneously and need not be performed in the order shown. The structures and functions presented as separate components in the exemplary configuration may be implemented as combined structures or components. Similarly, the structures and functions presented as individual components may be implemented as separate components. These and other variations, modifications, additions, and improvements fall within the scope of this paper's subject matter.

As used herein, any reference to "one embodiment" or "an embodiment" means that a particular element, feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. The appearances of the phrase "in one embodiment" in different places in the specification are not necessarily all referring to the same embodiment.

Some embodiments may be described using the expressions "coupled" and "connected" and their derivatives. For example, some embodiments may be described using the term "coupled" to indicate that two or more elements are in direct physical or electrical contact. However, the term "coupled" may also refer to two or more elements that are not in direct contact with each other, but still cooperate or interact with each other. The embodiments are not limited in this context.

As used herein, the terms "comprises," "comprising," "includes," "including," "has," "having," or any other variations thereof, are intended to be non-exclusive. For example, a process, method, object, or apparatus that comprises a list of elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such process, method, object, or apparatus. Furthermore, unless expressly stated to the contrary, "or" is intended to be inclusive and not exclusive. For example, condition A or B may be satisfied by any of the following: A is true (or exists) and B is false (or does not exist), A is false (or does not exist) and B is true (or exists), and both A and B are true (or exist).

In addition, the use of "a" or "an" is used to describe elements and components of the embodiments herein. This is merely for convenience and to give a general meaning to the description. This specification and the appended claims should be understood to include one or at least one, and the singular also includes the plural unless it is obvious that it means otherwise.

The detailed description is to be understood as examples and does not describe every possible embodiment because describing every possible embodiment would be impractical, even if it were possible. Numerous alternative embodiments could be implemented using either current technology or technology developed after the filing date of this application.

Claims (23)

1. A lighting device (104) configured to inactivate MRSA bacteria in an environment (100), said lighting device comprising: An illumination element (256; 612) configured to provide light, wherein at least a first component (700) of the light comprises light having a wavelength between 400 nm and 420 nm, and at least a second component (704) of the light comprises light having a wavelength greater than 420 nm. The first component of the light has a minimum overall irradiance of 0.01 mW/ ^cm² , which is measured from any unshaded point 1.5 m away from any point on any outermost luminous surface of the lighting device in the environment. The light provided by the lighting element is emitted from a single light-emitting element (656) of the lighting element; and The light provided by the illumination element includes white light, the u’ and v’ coordinates of which on the 1976 CIE chromaticity diagram lie on a curve between 0.035 duv below and 0.035 duv above the Planck locus defined by the ANSI C78.377-2015 color standard. 2. The lighting device (104) according to claim 1, wherein the minimum overall irradiance is equal to 0.05mW/ ^cm² , 0.10mW/ ^cm² , 0.15mW/ ^cm² , 0.20mW/ ^cm² , 0.25mW/ ^cm² or 0.30mW/ ^cm² . 3. The lighting device (104) according to claim 1 or 2, wherein the radiant power at a 20-degree angle to the central axis of the light distribution is equal to 50% of the radiant power at the central axis of the light distribution, wherein the radiant power at the 20-degree angle and the radiant power at the central axis are measured at equal distances from the lighting element (256; 612). 4. The lighting device (104) according to claim 3, wherein the radiant power at a 30-degree angle to the central axis of the light distribution is equal to 50% of the radiant power at the central axis of the light distribution, wherein the radiant power at the 30-degree angle and the radiant power at the central axis are measured at equal distances from the lighting element (256; 612). 5. The lighting device (104) according to claim 1 or 2, wherein the single light-emitting element (256; 612) comprises a light-emitting diode (LED) (256; 656). 6. The lighting device (104) according to claim 5 further includes means for maintaining the junction temperature of the LED (256; 656) below the maximum operating temperature of the LED (256; 656). 7. The lighting device (104) according to claim 1 or 2, wherein the light emitted by the lighting element (256; 612) has luminous flux on a cone that is angled downwards at 60 degrees from the lighting device and circumferentially surrounds the lowest point of the lighting device, and the luminous flux is greater than 15%, 20%, 25% or 30% of the total luminous flux of the light emitted by the lighting element. 8. The lighting device (104) according to claim 1 or 2 further includes at least one additional lighting element (656) configured to emit light having a wavelength between 400 nm and 420 nm. 9. The lighting device (104) according to claim 1 or 2 further includes a controller (120; 618) configured to control the lighting element (256; 612) in response to a control signal received from a user of the lighting device or from a central controller (76) remotely located relative to the lighting device. 10. The lighting device (104) according to claim 1 or 2, wherein the single light-emitting element comprises a light-emitting diode (LED) (256; 656) and a phosphorescent element, the phosphorescent element covering or disposed near the LED, the phosphorescent element being configured to generate the second component (704) of the light emitted by the light-emitting element (256; 612). 11. The lighting device (104) according to claim 1 or 2, wherein the first component (700) of the light comprises light of at least 4 watts having a wavelength between 400 nm and 420 nm. 12. A lighting device (104) configured to inactivate MRSA bacteria in an environment (100), said lighting device comprising: A single light-emitting element (656) configured to provide light, the single light-emitting element comprising: A single light-emitting diode (256; 656), said single light-emitting diode being configured to emit light having a wavelength between 400 nm and 420 nm. The light conversion element, relative to the single light-emitting diode arrangement, is arranged such that at least a first component (700) of the light emitted by the light-emitting diode travels through the light conversion element without change, and at least a second component (704) of the light emitted by the light-emitting diode is converted into light having a wavelength greater than 420 nm. Wherein, the first component of the light has a minimum overall irradiance of 0.01 mW/ ^cm² , which is measured from any unshaded point 1.5 m away from any point on any outermost luminous surface of the lighting device in the environment; and The light provided by the illumination element includes white light, the u’ and v’ coordinates of which on the 1976 CIE chromaticity diagram lie on a curve between 0.035 duv below and 0.035 duv above the Planck locus defined by the ANSI C78.377-2015 color standard. 13. The lighting device (104) according to claim 12, wherein the minimum overall irradiance is equal to 0.05 mW/ ^cm² , 0.10 mW/ ^cm² , 0.15 mW/ ^cm² , 0.20 mW/ ^cm² , 0.25 mW/ ^cm² or 0.30 mW/ ^cm² . 14. The lighting device (104) according to claim 12 or 13, wherein the radiant power at 20 degrees from the central axis of the light distribution is equal to 50% of the radiant power at the central axis of the light distribution, wherein the radiant power at 20 degrees and the radiant power at the central axis are measured at equal distances from the individual light-emitting elements (256; 656). 15. The lighting device (104) according to claim 12 or 13, wherein the light emitted by the single light-emitting element has luminous flux on a cone that is angled downwards at 60 degrees from the lighting device and circumferentially surrounds the lowest point of the lighting device, and the luminous flux is greater than 15%, 20%, 25% or 30% of the total luminous flux of the light emitted by the single light-emitting element. 16. The lighting device (104) according to claim 12 or 13 further includes means for maintaining the junction temperature of the individual light-emitting diode (256; 656) below the maximum operating temperature of the individual light-emitting diode (256; 656). 17. The lighting device (104) according to claim 12 or 13 further includes at least one additional light-emitting element (256; 656), said at least one additional light-emitting element being configured to emit light having a wavelength between 400 nm and 420 nm. 18. The lighting device (104) according to claim 12 or 13 further includes a controller (120; 618) configured to control the individual light-emitting element (256; 656) in response to a control signal received from a user of the lighting device or from a central controller (76) remotely located relative to the lighting device. 19. The lighting device (104) according to claim 12 or 13, wherein the light conversion element covers the single light-emitting diode. 20. The lighting device (104) according to claim 12 or 13, wherein the light conversion element is located away from the single light-emitting diode. 21. The lighting device (104) according to claim 12 or 13, wherein the light conversion element comprises a phosphorescent coating. 22. The lighting device (104) according to claim 12 or 13, wherein the first component (700) of the light comprises light of at least 4 watts having a wavelength between 400 nm and 420 nm. 23. A method for inactivating MRSA bacteria in the environment (100), the method comprising: Light is provided from lighting elements (256; 612) of a lighting device (104) installed in the environment, wherein the light provided by the lighting elements is generated from a single light-emitting element (656), wherein at least a first component (700) of the light has a wavelength between 400 nm and 420 nm and a minimum overall irradiance of 0.01 mW/ ^cm² , the minimum overall irradiance being measured from an unshaded point 1.5 m away from any point on any outermost emitting surface of the lighting device in the environment, wherein at least a second component (704) of the light has a wavelength greater than 420 nm, and wherein the light provided by the lighting elements comprises white light, the u', v' coordinates of which lie on a curve on the 1976 CIE chromaticity diagram, the curve being between 0.035 duv below and 0.035 duv above the Planck locus defined by the ANSI C78.377-2015 color standard.