Antiviral air-filtering lighting device

Abstract

A lighting device that comprises a housing, two light sources, at least one airway, an air filter in each airway, and an air circulation mechanism for each airway. The air filter is coated with an antiviral photocatalytic coating. The first light source contributes to the light output of the device, whereas the second light source activates the photocatalyst material in the antiviral photocatalytic coating on the air filter. As the air circulation mechanism forces the air through the air filter, the airborne microbials are trapped on the surface of the air filter, and subsequently killed and decomposed by the photocatalyst material in the antiviral photocatalytic coating. With different embodiments, the present disclosure transforms the regular lighting equipment to antiviral air-filtering equipment and brings wellness lighting to the daily life.

Claims

1. A lighting device comprises: a housing; two light sources comprising a first light source and a second light source; an airway; an air filter in the airway; an air circulation mechanism corresponding to the airway; wherein, in operation: the housing houses the two light sources, the at least one airway, and the air filter, the first light source emits predominantly visible light (>400 nm) and accounts for 100% of a light output of the lighting device, the second light source is concealed inside the housing and has no contribution to the light output of the lighting device, the at least one airway has an air inlet and an air outlet, the air circulation mechanism sucks an ambient air through the air inlet, forces the air through the air filter, and releases the air through the air outlet, the air filter traps airborne microbials on a surface thereof and has an antiviral photocatalytic coating on the surface, the second light source is positioned adjacent to the air filter and activates a photocatalyst material in the antiviral photocatalytic coating, and the airborne microbials trapped by the air filter are decomposed by the activated photocatalyst material in the antiviral photocatalytic coating.

2. A lighting device of claim 1, wherein the air circulation mechanism comprises a fan positioned in the airway.

3. A lighting device of claim 1, wherein the photocatalyst material in the antiviral photocatalytic coating on the air filter is activatable by visible light (>400 nm).

4. A lighting device of claim 1, wherein the second light source emits predominantly ultraviolet (UV) light (<400 nm).

5. A lighting device of claim 1, wherein the photocatalyst material in the antiviral photocatalytic coating on the air filter contains titanium oxide (TiO.sub.2).

6. A lighting device of claim 1, wherein the photocatalyst material in the antiviral photocatalytic coating on the air filter contains titanium oxide (TiO.sub.2) as a primary photocatalyst and an active metal ingredient such as silver, gold, copper, zinc, nickel, or a combination thereof, as the secondary photocatalyst.

7. A lighting device of claim 1, wherein the photocatalyst material in the antiviral photocatalytic coating on the air filter contains a noble metal nanoparticle gold (Au) or sliver (Ag) as a main photocatalyst.

8. A lighting device of claim 1, wherein the first light source comprises white-light light emitting diodes (LEDs) each emitting predominantly visible light (>400 nm).

9. A lighting device of claim 1, wherein the second light source comprises ultraviolet (UV) light emitting diodes (LEDs) each emitting predominantly UV light (<400 nm).

10. A lighting device of claim 1, wherein the first light source further comprises a third light source and a fourth light source, wherein both the third light source and the fourth light source emit predominantly visible light (>400 nm), and wherein a color temperature of the third light source is higher than a color temperature of the fourth light source.

11. A lighting device of claim 10, further comprising: a controller, wherein a color temperature of the first light source is tunable via the controller by mixing a combination ratio of the color temperatures of the third light source and the fourth light source, either manually or automatically according to a circadian schedule stored in a memory module of the controller.

12. A lighting device of claim 1, wherein the second light source is partially and not completely concealed inside the housing and accounts for 1% to 20% of the light output of the lighting device, and wherein the first light source accounts for 80% to 99% of the light output of the lighting device.

13. A lighting device of claim 12, wherein the first and the second light sources use a same type of light emitting diode (LED).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The accompanying drawings are included to aid further understanding of the present disclosure, and are incorporated in and constitute a part of the present disclosure. The drawings illustrate a select number of embodiments of the present disclosure and, together with the detailed description below, serve to explain the principles of the present disclosure. It is appreciable that the drawings are not necessarily to scale, as some components may be shown to be out of proportion to size in actual implementation in order to clearly illustrate the concept of the present disclosure.

(2) FIG. 1a schematically depicts a cross-section diagram of an LED screw-in lamp as an embodiment of the present disclosure.

(3) FIG. 1b schematically depicts a diagram of the screw-in lamp from another perspective.

(4) FIG. 1c schematically depicts a diagram of the screw-in lamp from yet another perspective.

(5) FIG. 1d schematically depicts the air filter and its antiviral photocatalytic coating of the lamp, and the trapped microbials.

(6) FIG. 2a schematically depicts an exterior view of an LED troffer fixture.

(7) FIG. 2b schematically depicts a look-through view of the troffer.

(8) FIG. 2c schematically depicts the air filter and its antiviral photocatalytic coating of the troffer, and the trapped microbials.

(9) FIG. 3 schematically depicts a diagram of an LED wall sconce fixture and its cross-section.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Overview

(10) Various implementations of the present disclosure and related inventive concepts are described below. It should be acknowledged, however, that the present disclosure is not limited to any particular manner of implementation, and that the various embodiments discussed explicitly herein are primarily for purposes of illustration. For example, the various concepts discussed herein may be suitably implemented in a variety of lighting apparatuses having different form factors.

(11) The present disclosure discloses a lighting device that comprises a housing, two light sources, at least one airway, an air filter in each airway, and an air circulation mechanism for each airway. The first light source emits visible light and accounts for 100% the light output of the lighting device. The second light source is concealed inside the housing, and it activates the photocatalyst material in the antiviral photocatalytic coating the air filter. The air circulation mechanism forces the ambient air through the air filter and the air filter traps airborne microbials. The trapped microbials are subsequently killed and decomposed by the activated photocatalyst material in the antiviral photocatalytic coating.

Example Implementations

(12) FIG. 1a-1c show an embodiment of the lighting device of the present disclosure in a form of an LED screw-in lamp 100. This lamp has a housing 101, the first light source 102, the second light source 103, one airway 104, and one fan 105 and one air filter 106. The first light source 102 comprises multiple LEDs on top of the lamp emitting predominantly white light in the >400 nm wavelength range, and accounts for 100% light output of the lighting device. The second light source 103 comprises multiple UV LEDs and are concealed inside the housing and has no contribution to the light output of the lighting device. The airway 104 has an air inlet 107 and an air outlet 108. The fan 105 and the air filter 106 are positioned inside the airway 104. The fan 105 sucks the ambient air through the air inlet 107, forces the air through the air filter 106, and releases the air through the air outlet 108. The air filter 106 has antiviral photocatalytic coating 109 on its surface. The second light source 103 is positioned adjacent to the air filter 106 for activating the photocatalyst material in the antiviral photocatalytic coating 109. In this embodiment, the second light source 103 is inside the airway 104.

(13) In FIG. 1d, as the air passes through the air filter 106, the airborne microbials 110 are trapped on the surface of the air filter. The photocatalyst material in the antiviral photocatalytic coating 109 activated by the second light source 103 kills and decomposes the trapped microbials 110. The photocatalyst material contains nano anatase-type TiO.sub.2 111 as its primary photocatalyst and nano silver 112 as its secondary photocatalyst. When using TiO.sub.2 and nano silver as photocatalyst, visible light LEDs can be used as the second light source 103 and still achieve adequate photocatalytic effect. It is also foreseeable to use metals other than nano silver as the secondary photocatalyst. Moreover, it is anticipated to use noble metal nanoparticle such as gold (Au) and silver (Ag) as the main photocatalyst in lieu of a semiconducting photocatalyst TiO.sub.2.

(14) FIGS. 2a and 2b show an embodiment of the lighting device of the present disclosure in a form of an LED troffer fixture 200. This troffer has a housing 201, the first light source 202a,202b, the second light source 203a,203b, two airways 204a,204b, two fans 205a,205b and two air filters 206a,206b. The first light source comprises six rows of LEDs on three PCBs. Out of the six rows of LEDs, three rows are 2700K LEDs 202a and the other three rows are 6500K LED 202b. The 2700K LEDs produce a lesser circadian stimulus and is more suitable for nighttime lighting, whereas the 6500K LED produce a higher circadian stimulus and is more suitable for daytime use. The combined light output of 2700K and 6500K LEDs sets the total light output of the lighting device. Since they each emits predominantly visible light in the >400 nm wavelength range, their combined light is also in the >400 nm wavelength range. A controller 212 is used to color-tune the light output of the light device by changing the mixing ratio of the light output of the 2700K LEDs 202a and the 6500K LEDs 202b. Moreover, a memory module 213 is used to store a circadian schedule. The controller 212 can thus color-tune the light output of the first light source automatically according the circadian schedule stored in the memory module 213. The circadian schedule will transition the color temperature of the first light source from warm white (2700K) to cold white (6500K) at dawn and revert the color temperature back to warm white at sunset, thus emulating color transition of the sunlight.

(15) The construction of the two airways 204a and 204b are the same, therefore the description below is on the airway 204a. The second light source 203a concealed in the housing comprises multiple UV LEDs and has no contribution to the light output of the lighting device. The airway 204a has an air inlet 207a and an air outlet 208a. The fan 205a and the air filter 206a are positioned inside the airway 204a. As the fan 205a forces the air through the airway 204a, the airborne microbials 210 are trapped on the surface of the air filter 206a. The surface air filter 206a is coated with an antiviral photocatalytic coating 209. As shown in FIG. 2c, the antiviral photocatalytic coating 209 contains only one type of photocatalyst material 211, TiO.sub.2. When the photocatalyst material 211 is activated by the second light source 203a, it kills and decomposes the trapped microbials 210. There is only one type of photocatalyst material TiO.sub.2 used in this case, because the larger number of UV LEDs 203a,203b provide adequate activation on TiO.sub.2.

(16) FIG. 3 show an embodiment of the lighting device of the present disclosure in a form of an LED wall sconce fixture 300. The diagram on the right is an exterior view of the wall sconce and the diagram on the left is an exploded view of the same. The housing includes the top cover 312, the bottom cover 313, the lens 310, the back plate 316, and two decorative rims 314,315. The first light source comprises multiple LEDs, and the second light also comprises multiple LEDs adjacent to the air filter 306 which is on the top of the wall sconce. The fan 306 is positioned at the bottom of the wall sconce. Both the fan 305 and the filter 306 are inside the airway 304. The airway 304 passes through the air chamber inside the housing 301 and has an inlet 307 and an outlet 308. The LED driver 309 is mounted on the back plate 316. Though not shown in FIG. 3, the structure of the air filter is similar to the one shown in FIG. 1d, where the antiviral photocatalytic coating on the surface of the air filter comprising TiO.sub.2 as the primary photocatalyst and nano silver as the secondary photocatalyst. The uniqueness of this wall sconce embodiment is in that the first light source 302 and the second light source 303 use the same type of LEDs. They only differ in their relative adjacency to the air filter 306. Moreover, the second light source also contributes to the light out of the wall sconce.

Additional and Alternative Implementation Notes

(17) Although the techniques have been described in language specific to certain applications, it is to be understood that the appended claims are not necessarily limited to the specific features or applications described herein. Rather, the specific features and examples are disclosed as non-limiting exemplary forms of implementing such techniques.

(18) As used in this application, the term or is intended to mean an inclusive or rather than an exclusive or. That is, unless specified otherwise or clear from context, X employs A or B is intended to mean any of the natural inclusive permutations. That is, if X employs A; X employs B; or X employs both A and B, then X employs A or B is satisfied under any of the foregoing instances. In addition, the articles a and an as used in this application and the appended claims should generally be construed to mean one or more, unless specified otherwise or clear from context to be directed to a singular form.