WO2023194177A1 - Edge-lit lighting device and fixture - Google Patents

Abstract

An edge-lit light guide panel (LGP) lighting device includes an LGP having a light emitting surface and one or more light receiving surfaces. The edge-lit LGP lighting device also includes a light source unit that includes light source segments that each include one or more light emitting diodes. The light source segments are positioned to emit lights into the LGP through the one or more light receiving surfaces. Each light source segment of the light source segments is contiguous with at least one other light source segment of the light source segments. The light source segments are controllable to change a light distribution pattern of an illumination light provided by the LGP lighting device through the light emitting surface.

Description

Edge-lit lighting device and fixture

TECHNICAL FIELD

The present disclosure relates generally to lighting solutions, and in particular to light distribution of lights provided by edge-lit lighting devices.

BACKGROUND

A typical edge-lit light fixture provides an illumination light through a broad surface of a light guide panel (LGP) of the light fixture. The illumination light results from a light from a light source that enters the LGP through one or more light receiving surfaces of the LGP. Some edge-lit light fixtures provide an illumination light that has a fixed light distribution pattern. For example, the distribution pattern of a light provided by an edge-lit light fixture may be fixed during manufacturing. In other cases, an edge-lit light fixture may include multiple light engines and other components to achieve a desired distribution pattern of the light provided by the edge-lit light fixture. The use of multiple light engines (e.g., light source units) and other components may add complexity and cost to edge-lit light fixtures. Thus, solutions that enable a relatively simpler control of the distribution pattern of light provided by edge-lit light fixtures may be desirable.

SUMMARY

In general, the present disclosure relates to lighting solutions, and in particular to light distribution of lights provided by edge-lit lighting devices. In an example embodiment, an edge-lit light guide panel (LGP) lighting device includes an LGP having a light emitting surface and one or more light receiving surfaces. The edge-lit LGP lighting device also includes a light source unit that includes light source segments that each include one or more light emitting diodes. The light source segments are positioned to emit lights into the LGP through the one or more light receiving surfaces. Each light source segment of the light source segments is contiguous with at least one light source segment of the light source segments. The light source segments are controllable to change a light distribution pattern of an illumination light provided by the LGP lighting device through the light emitting surface. In another example embodiment, an edge-lit LGP light fixture includes an LGP having a light emitting surface and one or more light receiving surfaces. The edge-lit LGP light fixture further includes a light source unit that includes light source segments that each include one or more light emitting diodes. The light source segments are positioned to emit lights into the LGP through the one or more light receiving surfaces. Each light source segment of the light source segments is contiguous with at least one light source segment of the light source segments. The edge-lit LGP light fixture further includes a driver configured to provide power to the light source unit and a control unit configured to control the light source segments to control a light distribution pattern of an illumination light provided by the LGP lighting device through the light emitting surface.

These and other aspects, objects, features, and embodiments will be apparent from the following description and the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

Reference will now be made to the accompanying figures, which are not necessarily to scale, and wherein:

Fig. 1 illustrates an edge-lit lighting device according to an example embodiment;

Figs. 2A - 2C illustrate lighting distribution patterns of a light that can be provided by the lighting device of Fig. 1 according to example embodiments;

Fig. 3 illustrates an edge-lit lighting device according to another example embodiment;

Fig. 4 illustrates a light fixture including the lighting device of Fig. 3 according to an example embodiment;

Fig. 5 illustrates a circuit diagram of the lighting device of Fig. 3 according to an example embodiment;

Fig. 6 illustrates a block diagram of the control unit of the light fixture of Fig. 4 according to an example embodiment;

Fig. 7 illustrates a block diagram of the control unit of the light fixture of Fig. 4 according to another example embodiment; and

Fig. 8 illustrates an edge-lit lighting device according to another example embodiment.

The drawings illustrate only example embodiments and are therefore not to be considered limiting in scope. The elements and features shown in the drawings are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of the example embodiments. Additionally, certain dimensions or placements may be exaggerated to help visually convey such principles. In the figures, reference numerals designate like or corresponding, but not necessarily identical, elements.

DETAILED DESCRIPTION OF THE EXAMPLE EMBODIMENTS

In the following paragraphs, particular embodiments will be described in further detail by way of example with reference to the figures. In the description, well known components, methods, and/or processing techniques are omitted or briefly described. Furthermore, reference to various feature(s) of the embodiments is not to suggest that all embodiments must include the referenced feature(s).

Turning now to the drawings, example embodiments are described. Fig. 1 illustrates an edge-lit lighting device 100 according to an example embodiment. For example, Fig. 1 may illustrate a bottom view of the edge-lit lighting device 100. The lighting device 100 may be included in a light fixture such as a wall sconce or another type of light fixture. In some example embodiments, the lighting device 100 includes a light guide panel (LGP) 102 and a light source unit 104. The LGP 102 may have a light emitting surface 106 and multiple light receiving surfaces 110, 112, 114, 116, 118. In general, the light emitting surface 106 is a relatively broad surface, and the light receiving surfaces 110-118 are relatively narrow surfaces. The LGP 102 may also include another broad surface that is on an opposite side of the LGP 102 from the light emitting surface 106 as can be readily understood by those of ordinary skill in the art with the benefit of this disclosure. The LGP 102 may also include a narrow surface 108 that extends between the light receiving surfaces 116 and 118 at the perimeter of the LGP 102.

In some example embodiments, the light source unit 104 may include multiple light source segments 120, 122, 124, 126, 128. The light source segments 120-128 may each include a printed circuit board (PCB) and light emitting diodes (LEDs) attached to the PCB. Alternatively, the light source unit 104 may include a single piece circuit board, and the light source segments 120-128 may be sections of the single piece circuit board. For example, the light source unit 104 may include a metal core PCB (MCPCB) that includes LEDs attached thereto, and the light source segments 120-128 may be sections of the MCPCB. As another example, the light source unit 104 may include a flexible printed circuit (FPC) that includes LEDs attached thereto, and the light source segments 120-128 may be sections of the FPC. In some example embodiments, the light source segments 120-128 may each be contiguous with at least one other light source segment of light source segment 120-128. For example, the light source segment 120 is contiguous with the light source segments 122, 124, and the light source segment 122 is contiguous with the light source segments 120, 126. As another example, the light source segment 124 is contiguous with the light source segments 120, 128. As yet another example, the light source segment 126 is contiguous with the light source segment 122. As yet another example, the light source segment 128 is contiguous with the light source segment 124.

In some example embodiments, the lighting device 100 may emit an illumination light through the light emitting surface 106 of the LGP 102. The illumination light may result from one or more lights provided by one or more of the light source segments 120-128 and that enter the LGP 102 through one or more of the light receiving surfaces 110-118.

In some example embodiments, the light source segments 120-128 are positioned to emit lights into the LGP 102 through the light receiving surfaces 110-118. For example, the light source segment 120 may be positioned adjacent to the light receiving surface 110 of the LGP 102. LEDs 130 as well as other LEDs of the light source segment 120 may emit a light into the LGP 102 through the light receiving surface 110. The light source segment 120 may be parallel to the light receiving surface 110 as shown in Fig. 1. The light source segment 122 may be positioned adjacent to the light receiving surface 112 of the LGP 102. LEDs of the light source segment 122 may emit a light into the LGP 102 through the light receiving surface 112. The light source segment 124 may be positioned adjacent to the light receiving surface 114 of the LGP 102. LEDs of the light source segment 124 may emit a light into the LGP 102 through the light receiving surface 114. The light source segment 126 may be positioned adjacent to the light receiving surface 116 of the LGP 102. LEDs of the light source segment 126 may emit a light into the LGP 102 through the light receiving surface 116. The light source segment 128 may be positioned adjacent to the light receiving surface 118 of the LGP 102. LEDs of the light source segment 128 may emit a light into the LGP 102 through the light receiving surface 118.

In some example embodiments, the light source segments 122 and 124 may be symmetrically positioned on opposite sides of the LGP 102. The light source segments 122 and 124 may emit lights into the LGP 102 through the light receiving surfaces 112 and 114, respectively. The light receiving surfaces 112 and 114 may be contiguous with the light receiving surface 110 on opposite sides of the LGP 102, where the light receiving surface 110 is between the light receiving surfaces 112 and 114. The light source segment 122 may be parallel to the light receiving surface 112 as shown in Fig. 1 and may be angled outwardly relative to an axis (not shown) that is perpendicular to and extends through the light source segment 120. Alternatively, instead of being parallel to the light receiving surface 112, the light source segment 122 may be spaced more from the light receiving surface 112 as the light source segment 122 extends away the light source segment 120. That is, the gap between the light source segment 122 and the light receiving surface 112 may be larger at one end of the light receiving surface 112 than at another end of the light receiving surface 112. As a non-limiting example, the light source segment 122 may be angled away from the light receiving surface 112 by 5 degrees. In some example embodiments, the light source segment 122 may be angled away from the light receiving surface 112 by more or less than 5 degrees without departing from the scope of this disclosure.

In some example embodiments, the light source segment 124 may be parallel to the light receiving surface 114 as shown in Fig. 1 and may be angled outwardly relative to an axis (not shown) that is perpendicular to and extends through the light source segment 120. Alternatively, instead of being parallel to the light receiving surface 114, the light source segment 124 may be spaced more from the light receiving surface 114 as the light source segment 124 extends away the light source segment 120 on the opposite side from the light source segment 122. To illustrate, the inside angle between the light receiving surfaces 110 and 112 may be smaller than the inside angle between the light source segments 120 and 122, and the inside angle between the light receiving surfaces 110 and 114 may be smaller than the inside angle between the light source segments 120 and 124. That is, the gap between the light source segment 124 and the light receiving surface 114 may be larger at one end of the light receiving surface 114 than at another end of the light receiving surface 114. As a nonlimiting example, the light source segment 124 may be angled away from the light receiving surface 114 by 5 degrees. In some example embodiments, the light source segment 124 may be angled away from the light receiving surface 114 by more or less than 5 degrees without departing from the scope of this disclosure.

In some example embodiments, the light receiving surface 116 may be contiguous with the light receiving surface 112, and the light receiving surface 118 may be contiguous with the light receiving surface 114. The light source segments 126 and 128 may be symmetrically positioned on opposite sides of the LGP 102 next to the light receiving surfaces 116 and 118, respectively. The light source segment 126 may be parallel to the light receiving surface 116 as shown in Fig. 1 and may be angled outwardly relative to an axis (not shown) that is perpendicular to and extends through the light source segment 120. For example, the light source segment 126 may be angled outwardly less than the light source segment 122. Alternatively, instead of being parallel to the light receiving surface 116, the light source segment 126 may be spaced more from the light receiving surface 116 as the light source segment 126 extends away the light source segment 122. That is, the gap between the light source segment 126 and the light receiving surface 116 may be larger at one end of the light receiving surface 116 than at the other end of the light receiving surface 116. As a non-limiting example, the light source segment 126 may be angled away from the light receiving surface 116 by 10 degrees. In some example embodiments, the light source segment 126 may be angled away from the light receiving surface 116 by more or less than 10 degrees without departing from the scope of this disclosure.

In some example embodiments, the light source segment 128 may be parallel to the light receiving surface 118 as shown in Fig. 1 and may be angled outwardly relative to an axis (not shown) that is perpendicular to and extends through the light source segment 120. For example, the light source segment 128 may be angled outwardly less than the light source segment 124. Alternatively, instead of being parallel to the light receiving surface 118, the light source segment 128 may be spaced more from the light receiving surface 118 as the light source segment 128 extends away the light source segment 124 on the opposite side from the light source segment 126. That is, the gap between the light source segment 128 and the light receiving surface 118 may be larger at one end of the light receiving surface 118 than at the other end of the light receiving surface 118. As a non-limiting example, the light source segment 128 may be angled away from the light receiving surface 118 by 10 degrees. In some example embodiments, the light source segment 128 may be angled away from the light receiving surface 118 by more or less than 10 degrees without departing from the scope of this disclosure.

In some example embodiments, each one of the light source segments 120-128 may be controllable to turn on, turn off, and change intensity of the light provided by the particular light source segment. For example, a control unit may control electrical switches to control whether individual ones of the light source segments 120-128 are powered on and powered off. To illustrate, the light source segments 120-128 may each include an electrical switch that is controlled by the control unit via electrical wires. As another example, light segment pairs from among the light source segments 120-128 may be controlled together. For example, the light source segments 122 and 124 may be powered on and off together, and the light source segments 126 and 128 may be powered on and off together. The light source segment 120 may also include sub-segments that may be powered on and off together. As yet another example, the control unit may control the amount of power that is provided to each one or pair of the light source segments 120-128 that is/are powered on.

In some example embodiments, the light distribution of the illumination light that is provided by the lighting device 100 may be changed by turning on or off one or more of the light source segments 120-128. Alternatively or in addition, the light distribution of the illumination light may also be changed by changing the intensity levels of the lights provided by the individual light source segments of the light source segments 120-128. For example, the intensity level of a light provided by a particular one of the light source segments 120-128 may be changed by adjusting the current provided to the particular light source segment.

To illustrate, Figs. 2A - 2C show lighting distribution patterns of the illumination light provided by the lighting device 100 of Fig. 1 according to example embodiments. The light distribution pattern of the illumination light shown in Fig. 2A may result from the light source segments 126 and 128 providing lights that have higher intensity levels than the lights provided by the light source segments 120-124. For example, the light source segments 126, 128 may each be provided with more current (e.g., twice) than the light source segments 120-124 such that the lights entering the LGP 102 through the light receiving surfaces 116, 118 have higher intensity levels than the lights entering the LGP 102 through the light receiving surfaces 110-114. The orientations of the light source segments 126 and 128 and the light receiving surfaces 116 and 118 may result in the light distribution pattern (e.g., wide throw) shown in Fig. 2A when lights emitted by the light source segments 126, 128 have higher intensities than the lights emitted by the light source segments 120-124.

In some example embodiments, the light distribution pattern shown in Fig. 2B may result from the light source segments 120-128 providing lights having the same or substantially the same intensity level. For example, the same amount of current may be provided to each one of the light source segments 120-128. The orientations of the light source segments 122-128 and the light receiving surfaces 112-118 relative to the light source segment 120 and the light receiving surface 110 may result in the light distribution pattern (e.g., medium throw) shown in Fig. 2B when lights emitted by the light source segments 120- 128 have substantially the same level of intensity.

In some example embodiments, the light distribution pattern shown in Fig. 2C may result from the light source segment 120 providing a light that has a higher intensity level than the lights provided by the light source segments 122-128. For example, the amount of current provided to the light source segment 120 may be twice the amount of current provided to each one of the light source segments 122-128.

In general, the amount of current provided to each of the light source segments 120-128 may be adjusted without changing the total amount of current provided to the light source unit 104 as can be readily understood by those of ordinary skill in the art with the benefit of this disclosure. Alternatively, the amount of current provided to each of the light source segments 120-128 may be changed resulting in a change in the total amount of current provided to the light source unit 104.

By using the light source unit 104 that includes multiple light source segments 120-128 and by turning on/off or by adjusting the power provided to the light source segments 120-128, the light distribution of the light provided by the lighting device 100 through the light emitting surface 106 may be adjusted. By positioning the light source segments 122-128 such that opposite ends of each one of the light source segments 122-128 are spaced differently from the respective one of light receiving surfaces 112-118, desired light distribution patterns of the illumination light may be achieved.

In some alternative embodiments, the LGP 102 is shown in Fig. 1 may have other shapes without departing from the scope of this description. For example, the LGP 102 may have more or fewer light receiving surfaces than shown in Fig. 1 without departing from the scope of this disclosure. In some alternative embodiments, the light source unit 104 may include more or fewer LEDs than shown without departing from the scope of this disclosure.

Fig. 3 illustrates an edge-lit lighting device 300 according to an example embodiment. For example, Fig. 3 may be a bottom view of the edge-lit lighting device 300. The lighting device 300 may be included in a light fixture such as a wall sconce or another type of light fixture. In some example embodiments, the lighting device 300 includes a light guide panel (LGP) 302 and a light source unit 304. The LGP 302 may have a light emitting surface 306 and multiple light receiving surfaces 310, 312, 314. In general, the light emitting surface 306 is a relatively broad surface, and the light receiving surfaces 310-314 are relatively narrow surfaces. The LGP 302 may also include another broad surface that is on an opposite side from the light emitting surface 306 as can be readily understood by those of ordinary skill in the art with the benefit of this disclosure. The LGP 302 may also include a narrow surface 308 that extends between the light receiving surfaces 312 and 314 at the perimeter of the LGP 302.

In some example embodiments, the light source unit 304 may include multiple light source segments 316, 318, 320. The light source unit 104 may include a single piece circuit board, and the light source segments 316-320 may be sections of the single piece circuit board. For example, the light source unit 304 may include a metal core printed circuit board (MCPCB) that includes light emitting diodes (LEDs) attached thereto, and the light source segments 316-320 may be sections of the MCPCB. As another example, the light source unit 104 may include a flexible printed circuit (FPC) that includes LEDs attached thereto, and the light source segments 316-320 may be sections of the FPC.

In some example embodiments, the light source segment 316 includes LEDs such as the LED 322. The light source segment 316 may also include an electrical switch 328. For example, the electrical switch 328 may be a metal oxide semiconductor (MOS) switch. The electrical switch 328 may be controlled to control whether power is provided to the LEDs of the light source segment 316.

In some example embodiments, the light source segment 318 includes LEDs such as the LED 324. The light source segment 318 may also include an electrical switch 330. For example, the electrical switch 330 may be a metal oxide semiconductor (MOS) switch. The electrical switch 330 may be controlled to control whether power is provided to the LEDs of the light source segment 318.

In some example embodiments, the light source segment 320 includes LEDs such as the LED 326. The light source segment 318 may also include an electrical switch 332. For example, the electrical switch 332 may be a metal oxide semiconductor (MOS) switch. The electrical switch 332 may be controlled to control whether power is provided to the LEDs of the light source segment 320. One or more of the electrical switches 328-332 may serve to protect the LEDs of the light source segments 316-320 against damage by the LGP 302 by preventing the LGP 302 from coming in direct contact with the LEDs. For example, the height of the electrical switches 328-332 may be more than that of the LEDs.

In some example embodiments, the light source segments 316-320 may each be contiguous with at least one other light source segment of the light source segment 316- 320. For example, the light source segment 316 is contiguous with the light source segments 318 and 320. The light source segment 318 is contiguous with the light source segments 316, and the light source segment 320 is contiguous with the light source segments 316.

In some example embodiments, the lighting device 300 may emit an illumination light through the light emitting surface 306 of the LGP 302. The illumination light may result from one or more lights provided by one or more of the light source segments 316-320 and that enter the LGP 302 through one or more of the light receiving surfaces 310-314. To illustrate, the light source segments 316-320 are positioned to emit lights into the LGP 302 through the light receiving surfaces 310-314. For example, the light source segment 316 may be positioned adjacent to the light receiving surface 310 of the LGP 302. The LED 322 as well as other LEDs of the light source segment 316 may emit a light into the LGP 302 through the light receiving surface 310. The light source segment 318 may be positioned adjacent to the light receiving surface 312 of the LGP 302. The LED 324 as well as other LEDs of the light source segment 318 may emit a light into the LGP 302 through the light receiving surface 312. The light source segment 320 may be positioned adjacent to the light receiving surface 314 of the LGP 302. The LED 326 as well as other LEDs of the light source segment 320 may emit a light into the LGP 302 through the light receiving surface 314.

In some example embodiments, the light source segments 316 and 320 may be symmetrically positioned on opposite sides of the LGP 302. The light source segments 316 and 320 may emit lights into the LGP 302 through the light receiving surfaces 312 and 314, respectively. The light receiving surfaces 312 and 314 may be contiguous with the light receiving surface 310 on opposite sides of the LGP 302. The light source segment 316 may be parallel to the light receiving surface 310. The light source segment 318 may also be parallel to the light receiving surface 312. Alternatively, the light source segment 318 may be spaced more from the light receiving surface 312 as the light source segment 318 extends away from the light source segment 316. The light source segment 320 may be parallel to the light receiving surface 314. Alternatively, the light source segment 320 may be spaced more from the light receiving surface 314 as the light source segment 320 extends away from the light source segment 316 on the opposite side of the LGP 302 from the light source segment 318.

In some example embodiments, each one of the light source segments 316-320 may be controllable to turn on, turn off, and change intensity of the light provided by the particular light source segment. For example, the light distribution of the illumination light provided by the lighting device 300 may be changed by turning on or off one or more of the light source segments 316-320. To illustrate, the light source segment 316 may be powered on and off using the electrical switch 328, the light source segment 318 may be powered on and off using the electrical switch 330, and the light source segment 320 may be powered on and off using the electrical switch 332. Alternatively or in addition, the light distribution of the illumination light may be changed by changing the intensity levels of the lights provided by each light source segment of the light source segments 316-320. For example, the intensity levels of lights provided by the light source segments 316-320 may be changed by adjusting the current provided to one or more of the light source segments 316-320.

In some alternative embodiments, the LGP 302 shown in Fig. 3 may have other shapes without departing from the scope of this description. For example, the LGP 302 may have more or fewer light receiving surfaces than shown in Fig. 3 without departing from the scope of this disclosure. In some example embodiments, the light source segments 316- 320 may be identical light source segments. Alternatively, one or more of the light source segments 316-320 may include different types and/or a different number of LEDs without departing from the scope of this disclosure. In some alternative embodiments, one or more of the switches 328-332 may be omitted from corresponding ones of the light source segments 316-320 without departing from the scope of this disclosure. For example, the switches 328- 332 may be located on the light source unit 304 but separate from the light source segments 316-320. In some alternative embodiments, the switches 328-332 may be integrated in the control unit 404 without departing from the scope of this disclosure. In some alternative embodiments, the light source unit 304 may include more or fewer LEDs than shown without departing from the scope of this disclosure.

Fig. 4 illustrates a light fixture 400 including the lighting device 300 of Fig. 3 according to an example embodiment. For example, the light fixture 400 may be a wall sconce or another type of light fixture. Referring to Figs. 3 and 4, in some example embodiments, the light fixture 400 includes the lighting device 300, a driver 402, and a control unit 404. The control unit 404 may control the light distribution pattern of the light provided by the lighting device 300 by turning on and off the electrical switches 328-332 of the lighting device 300 and by controlling the amount of current the driver 402 provides to the light source unit 304.

In some example embodiments, the light fixture 400 may also include a sensor device 406 that senses the presence of a person within a detection range of the sensor device 406. For example, the sensor device 406 may be a motion sensor, and the control unit 404 may control the electrical switches 328-332 of the lighting device 300 to adjust the lighting distribution of the illumination light provided by the light fixture 400 based on sensor information from the sensor device 406. To illustrate, the sensor device 406 may include multiple sensor elements that sense motion in different areas with respect to the lighting device 300, and the control unit 404 may control whether one or more of the light source segments 316-320 emit lights into the LGP 302 based on motion detection indicated by one or more of the sensor elements. For example, a sensor element of the sensor device 406 may be associated with the light source segment 316, another sensor element of the sensor device 406 may be associated with the light source segment 318, and another sensor element of the sensor device 406 may be associated with the light source segment 320. The control unit 404 may turn on the electrical switch 328 if a motion detection is indicated by the sensor element associated with the light source segment 316. The control unit 404 may turn on the electrical switch 330 if a motion detection is indicated by the sensor element associated with the light source segment 318. The control unit 404 may turn on the electrical switch 332 if a motion detection is indicated by the sensor element associated with the light source segment 320. If motion is not detected by any of the sensor elements of the sensor device 406, the control unit 404 may turn off all of the electrical switches 328-332.

In some example embodiments, the control unit 404 may control the electrical switches 328-332 using control signals provided to the light source unit 304 via electrical wires 412. The driver 402 may provide current to the light source segments 316-320 via electrical wires 414 that extend through the control unit 404. For example, electrical wires 408 extending between the driver 402 and the control unit 404 may be connected to the electrical wires 414. Alternatively, the driver 402 may provide current to the light source segments 316-320 using electrical wires that do not pass through the control unit 404 as can be readily understood by those of ordinary skill in the art with the benefit of this disclosure.

In some example embodiments, the control unit 404 may control the amount of current provided by the driver 402 to the light source segments 316-320. For example, the control unit 404 may provide one or more control signals to the driver 402 via one or more electrical wires 410. The one or more control signals may be, for example, 0-10V dim control signal(s) that range between 0 and 10 volts corresponding to proportional current amounts to be provided by the driver 402. For example, the driver 402 may provide to the light source unit 304 an amount of current corresponding to the voltage level indicated by the control signal as can be readily understood by those of ordinary skill in the art with the benefit of this disclosure.

Fig. 5 illustrates a circuit diagram 500 of the lighting device 300 of Fig. 3 according to an example embodiment. Referring to Figs. 3-5, in some example embodiments, LED-switch groups 502, 504, 506 shown in Fig. 5 may correspond to the light source segments 316, 318, 320, respectively, of the light source unit 304 shown in Figs. 3 and 4. For example, the LED-switch group 502 may include the electrical switch 328 and LEDs 508 that correspond to the LEDs of the light source segment 316. The LED-switch group 504 may include the electrical switch 330 and LEDs 510 that correspond to the LEDs of the light source segment 318. The LED-switch group 506 may include the electrical switch 332 and LEDs 512 that correspond to the LEDs of the light source segment 320.

In some example embodiments, the driver 402 may provide power to one or more of the LEDs 508, 510, 512 using the electrical wires 414 depending on the states of the switches 328-332. To illustrate, the control unit 404 may provide individual control signals to each one of the switches 328-332 via the electrical wires 412 to control whether each one of the switches 328-332 is closed/on or open/off The control unit 404 may turn on and off the lights provided by the LEDs 508, 510, 512 by controlling the switches 328-332. The control unit 404 may control (e.g., set or change) the distribution pattern of the illumination light provided by the light fixture 400 by turning on one or more of the switches 328-332 and by turning off the remaining ones of the switches 328-332.

In some example embodiments, the control unit 404 may also control (e.g., set or change) the distribution pattern of the illumination light provided by the light fixture 400 by controlling the amount of current provided by the driver 402 via the electrical wires 414. For example, the control unit 404 may control the driver 402 such that the driver 402 provides a first amount of current to the light source unit 304 under some conditions and a second amount of current under other conditions. To illustrate, the control unit 404 may control the amount of current provided by the driver 402 to the light source unit 304 depending on whether motion detection is indicated by the sensor device 406.

In some example embodiments, the control unit 404 may control the amount of current provided to the light source unit 304 by the driver 402 depending on how many of the electrical switches 328-332 are on/closed. To illustrate, when all of the electrical switches 328-332 are on/closed, the control unit 404 may control the driver 402 such that the driver 402 provides a maximum current to the light source unit 304. The maximum current may refer to the maximum amount of current that the driver 402 is configured to provide to the light source unit 304. When one or two of the electrical switches 328-332 are off/open, the control unit 404 may control the driver 402 such that the driver 402 provides less than the maximum current. In some alternative embodiments, the control unit 404 may control the driver 402 to provide the same amount of current regardless of how many of the electrical switches 328-332 are on.

In some alternative embodiments, the light fixture 400 may include the lighting device 100 instead of the lighting device 300 without departing from the scope of this disclosure. In some alternative embodiments, the light fixture 400 may include other components without departing from the scope of this disclosure. In some alternative embodiments, the driver 402 and the control unit 404 may be integrated in a single device. In some alternative embodiments, the driver 402, the control unit 404, the sensor device 406, and the lighting device 300 may be connected in a different configuration than shown without departing from the scope of this disclosure. In some alternative embodiments, the sensor device 406 may be physically connected to the lighting device 300 without departing from the scope of this disclosure.

Fig. 6 illustrates a block diagram of the control unit 404 of the light fixture 400 of Fig. 4 according to an example embodiment. Referring to Figs. 4 and 6, in some example embodiments, the control unit 404 includes a controller 602 and a direct-current to direct-current (DC/DC) converter 604. The control unit 404 may receive power from the driver 402 via Vin+ and Vin- ports of the control unit 404. For example, the Vin+ and Vin- ports of the control unit 404 may be connected to electrical wires 408 shown in Fig. 4. The Vin+ and Vin- ports may be connected internally to the LED+ and LED- ports of the control unit 404, where the LED+ and LED- ports may be connected to the electrical wires 414 shown in Figs. 4 and 5 to provide power to the light source unit 304 of the lighting device 300.

In some example embodiments, the DC/DC converter 604 may generate from the voltage provided by the driver 402 at the Vin+ and Vin- ports another voltage that is compatible with the controller 602. For example, the DC/DC converter 604 may generate 3.5 volts or 5 volts. The controller 602 may operate using the voltage from the DC/DC converter 604. To illustrate, the controller 602 may include a microcontroller and other components to perform operations described herein with respect to the control unit 404. For example, a microcontroller of the controller 602 may execute software code stored in a memory device to perform operations as can be readily understood by those of ordinary skill in the art with the benefit of this disclosure.

In some example embodiments, the controller 602 may generate switch control signals Cl, C2, C3 that may be used to turn on/off the electrical switches 328, 330, 332, respectively. For example, the controller 602 may generate the switch control signals Cl, C2, C3 based on switch configuration indicated in the software stored in the controller 602. Alternatively or in addition, the controller 602 may generate the switch control signals Cl, C2, C3 based on sensor information from the sensor device 406. Alternatively or in addition, the controller 602 may generate the 0-10V control signal based on user input provided to the controller 602 by a user. In some example embodiments, the controller 602 may generate a 0-10V control signal that is provided to the driver 402 via the one or more electrical wires 410. For example, the 0-10V control signal may be a dim control signal that ranges between 0 and 10 volts corresponding to proportional current amounts to be provided by the driver 402. The controller 602 may generate 0-10V control signal based on a setting indicated in the software stored in a memory device of the controller 602 and executed by the microcontroller of the controller 602. Alternatively or in addition, the controller 602 may generate the 0-10V control signal based on sensor information from the sensor device 406. For example, the controller 602 may use a voltage divider circuit to generate the 0-10V control signal. Alternatively or in addition, the controller 602 may generate the 0-10V control signal based on user input provided to the controller 602 by a user. In some alternative embodiments, the controller 602 may generate one or more driver control signals other than a 0-10V signal without departing from the scope of this disclosure.

In some alternative embodiments, the control unit 404 may include components than shown in Fig. 6 without departing from the scope of this disclosure. In some alternative embodiments, the controller 602 may include components other than described above without departing from the scope of this disclosure. In some example embodiments, the control unit 404 may generate more than three switch control signals without departing from the scope of this disclosure.

Fig. 7 illustrates a block diagram of the control unit 404 of the light fixture 400 of Fig. 4 according to another example embodiment. Referring to Figs. 4 and 7, in some example embodiments, the control unit 404 includes a controller 702, a DC/DC converter 704, and a dip-switch 706. The control unit 404 may receive power from the driver 402 via Vin+ and Vin- ports of the control unit 404. For example, the Vin+ and Vin- ports of the control unit 404 may be connected to electrical wires 408 shown in Fig. 4. The Vin+ and Vin- ports may be connected internally to the LED+ and LED- ports of the control unit 404, where the LED+ and LED- ports may be connected to the electrical wires 414 shown in Figs. 4 and 5 to provide power to the light source unit 304 of the lighting device 300.

In some example embodiments, the DC/DC converter 704 may generate from the voltage provided by the driver 402 at the Vin+ and Vin- ports a first voltage (e.g., 3.3 volts) that is compatible with the controller 702 and a second voltage (e.g., 12 volts) that is provided to the dip-switch 706. The controller 702 may operate using the voltage from the DC/DC converter 704. To illustrate, the controller 702 may include a microcontroller and other components to perform operations described herein with respect to the control unit 404. For example, a microcontroller of the controller 702 may execute software code stored in a memory device to perform operations as can be readily understood by those of ordinary skill in the art with the benefit of this disclosure.

In some example embodiments, the control unit 404 may generate switch control signals Cl, C2, C3 that may be used to turn on/off the electrical switches 328, 330, 332, respectively. For example, the voltage level of the switch control signals Cl, C2, C3 depends on whether a corresponding switch of the dip-switch 706 is open or closed. For example, when a switch of the dip-switch 706 corresponding to the switch control signal Cl is closed, the switch control signal Cl may be at 12 volts, and when the particular switch of the dip-switch 706 is open, the switch control signal Cl may be pulled down to 0 volt by of the resistor Rl. The voltages of the switch control signals C2 and C3 may each be at 12 volts when switches of the dip-switch 706 corresponding to the switch control signals C2 and C3 are closed, and the voltages of the switch control signals C2 and C3 may be pulled down to 0 volt by resistors R2 and R3, respectively, when the corresponding switches of the dip-switch 706 are open. The dip-switch 706 may be set at factory or during or after installation of the light fixture 400.

In some example embodiments, the controller 702 may generate the 0-10V control signal that is provided to the driver 402 via the one or more electrical wires 410 based on the voltage levels of the switch control signals Cl, C2, C3. For example, if all of the switch control signals Cl, C2, C3 are at 12 volts, the 0-10V control signal may indicate to the driver 402 to provide maximum current. As another example, if one of the switch control signals Cl, C2, C3 is at 0 volt and the others are at 12, the 0-10V control signal may indicate to the driver 402 to provide two-third of the maximum current. As another example, if one of the switch control signals Cl, C2, C3 is at 12 volts and the others are at 0 volt, the 0-10V control signal may indicate to the driver 402 to provide one-third of the maximum current. In some alternative embodiments, the 0-10V control signal may indicate to the driver 402 to provide other voltage levels depending on the voltages of the switch control signals Cl, C2, C3. In some alternative embodiments, the 0-10V control signal may indicate to the driver 402 to provide the maximum current regardless of the voltages of the switch control signals Cl, C2, C3.

In some alternative embodiments, the controller 702 may generate one or more driver control signals other than a 0-10V signal without departing from the scope of this disclosure. In some alternative embodiments, the control unit 404 may include components than shown in Fig. 7 without departing from the scope of this disclosure. In some alternative embodiments, the controller 702 may include components other than described above without departing from the scope of this disclosure. In some example embodiments, the control unit 404 may generate more than three switch control signals without departing from the scope of this disclosure.

Fig. 8 illustrates an edge-lit lighting device 800 according to an example embodiment. For example, Fig. 8 may be a bottom view of the edge-lit lighting device 800. The lighting device 800 may be included in a light fixture such as a wall sconce or another type of light fixture. In some example embodiments, the lighting device 800 may be used in the light fixture 400 of Fig. 4 instead of the lighting device 300 as can be readily understood by those of ordinary skill in the art with the benefit of this disclosure.

In some example embodiments, the lighting device 800 includes an LGP 802 and a light source unit 804. The LGP 802 may have a light emitting surface 806 and a light receiving surface 810 that extends around the circumference of the LGP 802. For example, the LGP 802 may have a circular shape as shown in Fig. 8, and the light source unit 804 may be spaced from the light receiving surface 810 of the LGP 802 and may extend around a portion of or the entire circumference of the LGP 802. In general, the light emitting surface 806 is a relatively broad surface, and the light receiving surface 810 is a relatively narrow surface as can be readily understood by those of ordinary skill in the art with the benefit of this disclosure. The LGP 802 may also include another broad surface that is on an opposite side from the light emitting surface 806 as can be readily understood by those of ordinary skill in the art with the benefit of this disclosure.

In some example embodiments, the light source unit 804 may include multiple light source segments 828, 830, 832. For example, the light source unit 804 may include a single piece circuit board, and the light source segments 828-832 may be sections of the single piece circuit board. To illustrate, the light source segment 828 be include LEDs 812, 814 and may extend between illustrative lines 836 and 838. The light source segment 830 may include LEDs 818, 820 and may extend between illustrative lines 834 and 836. The light source segment 832 may include LEDs 824 and may extend between illustrative lines 838 and 840. The light source unit 804 may include an MCPCB that includes the LEDs 812, 814, 818, 820, 824 attached thereto, where the light source segments 828-832 may be sections of the MCPCB. As another example, the light source unit 804 may include an FPC that includes the LEDs 812, 814, 818, 820, 824 attached thereto, where the light source segments 828-832 may be sections of the FPC. In some example embodiments, the light source segment 828 includes an electrical switch 816. For example, the electrical switch 816 may be a MOS switch. The electrical switch 816 may be controlled to control whether power is provided to the LEDs 812, 814 of the light source segment 828. For example, the control unit 404 shown in Fig. 4 may turn on and off the electrical switch 816 using a switch control signal such as, for example, the switch control signal Cl shown in Figs. 6 and 7. In some example embodiments, the light source segment 830 includes an electrical switch 822. For example, the electrical switch 822 may be a MOS switch. The electrical switch 822 may be controlled to control whether power is provided to the LEDs 818, 820 of the light source segment 830. For example, the control unit 404 shown in Fig. 4 may turn on and off the electrical switch 822 using a switch control signal such as, for example, the switch control signal C2 shown in Figs. 6 and 7. In some example embodiments, the light source segment 832 includes an electrical switch 826. For example, the electrical switch 826 may be a MOS switch. The electrical switch 826 may be controlled to control whether power is provided to the LEDs 824 of the light source segment 832. For example, the control unit 404 shown in Fig. 4 may turn on and off the electrical switch 826 using a switch control signal such as, for example, the switch control signal C3 shown in Figs. 6 and 7.

In some example embodiments, one or more of the electrical switches 816, 822, 826 may serve to protect the LEDs 812, 814, 818, 820, 824 of the light source segments 828-832 against damage by the LGP 802 by preventing the LGP 802 from coming in direct contact with the LEDs 812, 814, 818, 820, 824. For example, the height of the electrical switches 816, 822, 826 may be more than that of the LEDs.

In some example embodiments, the light source segments 828-832 may each be contiguous with at least one other light source segment of the light source segment 828- 832. For example, the light source segment 828 is contiguous with the light source segments 830 and 832. The light source segment 830 is contiguous with the light source segment 828, and the light source segment 832 is contiguous with the light source segment 828.

In some example embodiments, the lighting device 800 may emit an illumination light through the light emitting surface 806 of the LGP 802. The illumination light may result from one or more lights provided by one or more light source segments of the light source segments 828-832 and that enter the LGP 802 through the light receiving surface 810. To illustrate, the light source segments 828-832 are positioned to emit lights into the LGP 802 through portions of the light receiving surface 810. For example, the light source segment 828 may be positioned adjacent to a portion of the light receiving surface 810, and the LEDs 812, 814 of the light source segment 828 may emit a light into the LGP 802 mostly through that portion of the light receiving surface 810. The light source segment 830 may be positioned adjacent to another portion of the light receiving surface 810 that is adjacent to the first portion, and the LEDs 818, 820 of the light source segment 830 may emit a light into the LGP 802 mostly through that portion of the light receiving surface 810. The light source segment 832 may be positioned adjacent to yet another portion of the light receiving surface 810, and the LEDs 824 of the light source segment 832 may emit a light into the LGP 802 mostly through that portion of the light receiving surface 810.

In some example embodiments, each one of the light source segments 828-832 may be controllable to turn on, turn off, and change intensity of the light provided by the particular light source segment. For example, the light distribution of the illumination light provided by the lighting device 800 may be changed by turning on or off one or more of the light source segments 828-832. To illustrate, the light source segment 828 may be powered on and off using the electrical switch 816, the light source segment 830 may be powered on and off using the electrical switch 822, and the light source segment 832 may be powered on and off using the electrical switch 826. Alternatively or in addition, the light distribution of the illumination light may be changed by changing the intensity levels of the lights provided by the individual light source segments of the light source segments 828-832. For example, the intensity levels of lights provided by the light source segments 828-832 may be changed by adjusting the current provided to one or more of the light source segments 828-832.

In some alternative embodiments, the LGP 802 shown in Fig. 8 may have other shapes without departing from the scope of this description. For example, the LGP 802 may have other round but non-circular shapes. As another example, a portion of the LGP 802 not facing the light source unit 804 as shown in Fig. 8 may have a non-round shape. In some example embodiments, the light source segments 828-832 may be identical light source segment. Alternatively, one or more of the light source segments 828-832 may include different types and/or different number of LEDs without departing from the scope of this disclosure. In some alternative embodiments, one or more of the electrical switches 816, 822, 826 may be omitted from corresponding ones of the light source segments 828-832 without departing from the scope of this disclosure. For example, the electrical switches 816, 822, 826 may be different location than shown in Fig. 8. In some alternative embodiments, the electrical switches 816, 822, 826 may be integrated in the control unit 404 without departing from the scope of this disclosure. In some alternative embodiments, the light source unit 804 may include more or fewer LEDs than shown without departing from the scope of this disclosure.

Although particular embodiments have been described herein in detail, the descriptions are by way of example. The features of the embodiments described herein are representative and, in alternative embodiments, certain features, elements, and/or steps may be added or omitted. Additionally, modifications to aspects of the embodiments described herein may be made by those skilled in the art without departing from the scope of the following claims, the scope of which are to be accorded the broadest interpretation so as to encompass modifications and equivalent structures.

Claims

CLAIMS:

1. An edge-lit light guide panel (LGP) light fixture, comprising: an LGP (102, 302, 802) having a light emitting surface (106, 306, 806) and one or more light receiving surfaces (110-118, 310-314, 810); a light source unit (104, 304, 804) comprising light source segments (120-128, 316-320, 828-832) that each include one or more light emitting diodes (LEDs), wherein the light source segments are positioned to emit lights into the LGP through the one or more light receiving surfaces and wherein each light source segment of the light source segments is contiguous with at least one other light source segment of the light source segments; wherein one or more of the light source segments comprise an electrical switch (328-332); a driver (402) configured to provide power to the light source unit; and a control unit (404) configured to control the light source segments to control a light distribution pattern of an illumination light provided by the LGP lighting device through the light emitting surface and wherein the control unit is configured to control whether light source segment emit lights by controlling the electrical switches.

2. The edge-lit LGP light fixture of claim 1, further comprising a sensor device that senses a presence of a person, wherein the control unit is configured to control the light source segments based on sensor information from the sensor device.

3. The edge-lit LGP light fixture of claim 1, wherein the LGP (802) has a circular shape.

4. The edge-lit LGP light fixture of claim 3, wherein the light source unit (804) is positioned adjacent to a portion of a circumference of the LGP (802) that is less than an entirety of the circumference of the LGP (802).

5. The edge-lit LGP light fixture of claim 1, wherein a first segment (120) of the light source segments is positioned to emit a first light into the LGP (102) through a first light receiving surface (110) of the one or more light receiving surfaces, wherein a second segment (122) of the light source segments is positioned to emit a second light into the LGP (102) through a second light receiving surface (112) of the one or more light receiving surfaces, wherein a third segment (124) of the light source segments is positioned to emit a third light into the LGP (102) through a third light receiving surface (114) of the one or more light receiving surfaces, and wherein the second light receiving surface and the third light receiving surface are adjacent to and at opposite sides of the first light receiving surface.

6. The edge-lit LGP light fixture of claim 1, wherein the light source unit comprises a single piece circuit board having LEDs attached thereto and wherein the light source segments are sections of the single piece circuit.

7. The edge-lit LGP light fixture of claim 1, wherein each light source segment comprises an electrical switch and wherein the control unit is configured to control whether light source segment emit lights by controlling the electrical switches.