Patent Publication Number: US-11662079-B1

Title: Systems and methods for emulating natural daylight with an interior luminaire

Description:
TECHNICAL FIELD 
     This disclosure relates generally to home appliances, and in particular relates to emulating natural daylight with an interior luminaire. 
     BACKGROUND 
     Exposure to sunshine has been demonstrated to improve the sense of wellbeing and health; sunlight causes the body to release hormones, particularly serotonin, a key hormone that stabilizes our mood, feelings of well-being, and happiness. However, there are many places where having access to a sunlit window is simply impossible: for example, in the middle of large buildings, in basement rooms, or at high latitudes in winter when the sun sets early. Indeed, 4-6% of people are significantly affected by lack of sunlight—particularly in the winter months—due to a condition called Seasonal Affective Disorder (SAD). 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    illustrates an example electronic device. 
         FIG.  2 A  illustrates an example interior luminaire system. 
         FIG.  2 B  illustrates a close-up view of a first light source of  FIG.  2 A  emitting a cone of light onto a lens of  FIG.  2 A  through restriction by a mechanical assembly. 
         FIG.  3    illustrates a first light source comprising an integral lens that can restrict the emission angle of the first light source so that it directs light only at the lens with which it is paired. 
         FIG.  4    illustrates an array of first light sources and second light sources, wherein the first light sources are positioned at the focal points of the lenses and second light sources are positioned outside of a focal area of the lenses. 
         FIG.  5    illustrates a second example interior luminaire system. 
         FIG.  6 A  illustrates a beam of light produced by a steerable lens array before the lens array has been steered. 
         FIG.  6 B  illustrates steering a beam of light by moving lens array laterally. 
         FIG.  7 A  illustrates unintended crosstalk in a single-depth lens array. 
         FIG.  7 B  illustrates how second movable lenses can eliminate or reduce crosstalk. 
         FIG.  8    illustrates a third example interior luminaire system using a centralized light-engine. 
         FIG.  9    illustrates a fourth example interior luminaire system using light pipes. 
         FIG.  10 A  illustrates adjustable scattering with a white light source and a white PDLC film by varying an applied voltage. 
         FIG.  10 B  illustrates adjustable scattering with a white light source and a first color PDLC film by varying an applied voltage. 
         FIG.  10 C  illustrates adjustable color control with a white light source, a first color PDLC film, and a second color PDLC film by varying applied voltages. 
         FIG.  11 A  illustrates pulse width modification (PWM) control of a PDLC sheet to produce diffuse colored backlight and collimated sunlight with one light source. 
         FIG.  11 B  illustrates a graph of a duty cycle corresponding to the output depicted in  FIG.  11 A . 
         FIG.  12    illustrates a fifth example interior luminaire system using a steerable LED array with a collimator. 
         FIG.  13    illustrates an example method for emulating natural daylight with an interior luminaire system. 
         FIG.  14    illustrates an example computer system. 
     
    
    
     DESCRIPTION OF EXAMPLE EMBODIMENTS 
     Control System Overview 
       FIG.  1    illustrates an example electronic device  100 . In particular embodiments, the electronic device  100  may include, for example, any of various personal electronic devices  102 , such as a mobile phone electronic device, a tablet computer electronic device, a laptop computer electronic device, and so forth. In particular embodiments, as further depicted by  FIG.  1   , the personal electronic device  102  may include, among other things, one or more processor(s)  104 , memory  106 , sensors  108 , cameras  110 , a display  112 , input structures  114 , network interfaces  116 , a power source  118 , and an input/output (I/O) interface  120 . It should be noted that  FIG.  1    is merely one example of a particular implementation and is intended to illustrate the types of components that may be included as part of the electronic device  100 . 
     In particular embodiments, the one or more processor(s)  104  may be operably coupled with the memory  106  to perform various algorithms, processes, or functions. Such programs or instructions executed by the processor(s)  104  may be stored in any suitable article of manufacture that includes one or more tangible, computer-readable media at least collectively storing the instructions or routines, such as the memory  106 . The memory  106  may include any suitable articles of manufacture for storing data and executable instructions, such as random-access memory (RAM), read-only memory (ROM), rewritable flash memory, hard drives, and so forth. Also, programs (e.g., an operating system) encoded on such a computer program product may also include instructions that may be executed by the processor(s)  104  to enable the electronic device  100  to provide various functionalities. 
     In particular embodiments, the sensors  108  may include, for example, one or more cameras (e.g., depth cameras), touch sensors, microphones, motion detection sensors, thermal detection sensors, light detection sensors, time of flight (ToF) sensors, ultrasonic sensors, infrared sensors, or other similar sensors that may be utilized to detect various user inputs (e.g., user voice inputs, user gesture inputs, user touch inputs, user instrument inputs, user motion inputs, and so forth). The cameras  110  may include any number of cameras (e.g., wide cameras, narrow cameras, telephoto cameras, ultra-wide cameras, depth cameras, and so forth) that may be utilized to capture various 2D and 3D images. The display  112  may include any display architecture (e.g., AMLCD, AMOLED, micro-LED, and so forth), which may provide further means by which users may interact and engage with the electronic device  100 . In particular embodiments, as further illustrated by  FIG.  1   , one more of the cameras  110  may be disposed behind, underneath, or alongside the display  112  (e.g., one or more of the cameras  110  may be partially or completely concealed by the display  112 ), and thus the display  112  may include a transparent pixel region and/or semi-transparent pixel region through which the one or more concealed cameras  110  may detect light, and, by extension, capture images. It should be appreciated that the one more of the cameras  110  may be disposed anywhere behind or underneath the display  110 , such as at a center area behind the display  110 , at an upper area behind the display  110 , or at a lower area behind the display  110 . 
     In particular embodiments, the input structures  114  may include any physical structures utilized to control one or more global functions of the electronic device  100  (e.g., pressing a button to power “ON” or power “OFF” the electronic device  100 ). The network interface  116  may include, for example, any number of network interfaces suitable for allowing the electronic device  100  to access and receive data over one or more cloud-based networks (e.g., a cloud-based service that may service hundreds or thousands of the electronic device  100  and the associated users corresponding thereto) and/or distributed networks. The power source  118  may include any suitable source of power, such as a rechargeable lithium polymer (Li-poly) battery and/or an alternating current (AC) power converter that may be utilized to power and/or charge the electronic device  100  for operation. Similarly, the I/O interface  120  may be provided to allow the electronic device  100  to interface with various other electronic or computing devices, such as one or more auxiliary electronic devices. 
     In particular embodiments, the electronic device  100  is a mobile device or remote-control device that is programmed to communicate with an interior luminaire system  190  that comprises a compatible I/O interface. In other particular embodiments, the electronic device  100  is not a mobile device, but is instead integrated into the interior luminaire system  190 . As an example, and not by way of limitation, any of the one or more processors  104 , the memory  106 , the I/O interface  120 , or other components of the electronic device may be integrated into a system on a chip (SoC), which is further integrated into the interior luminaire system  190 . In particular embodiments, the electronic device  100  may be used to control the interior luminaire system  190 . As an example, and not by way of limitation, the electronic device  100  may be programmed to control the operation of one or more light sources and one or more lenses of the interior luminaire system, as explained herein with greater specificity. As an example, and not by way of limitation, the electronic device  100  may be programmed to control the orientation of one or more light sources or lenses, or the quality, color, or other characteristics of the light emitted from the one or more light sources. As an example, and not by way of limitation, the electronic device  100  may be programmed to control a movable beam of light, as further explained herein. Although this disclosure describes the electronic device  100  controlling the interior luminaire system  190  in a particular manner, this disclosure contemplates the electronic device  100  controlling the interior luminaire system  190  in any suitable manner, in accordance with the various embodiments of the interior luminaire system  190 . 
     Interior Luminaire System for Emulating Natural Daylight 
     In particular embodiments, this disclosure provides a luminaire which mimics a window with realistic sunshine, and which may be used for places or times when it would otherwise be impossible to have natural light. Such a luminaire could have wide application as an aid to improving health and wellness for individuals without adequate access to natural daylight. In particular embodiments, the luminaire may emulate natural daylight by providing emulated sunlight using one or more first light sources and emulated skylight using one or more second light sources. 
     In particular embodiments, an intense beam of light can be generated by an array of light sources in combination with a (parallel) array of lenses. The light sources can be placed at the focus of the lenses so that the emerging light is collimated—producing a beam, the size of the lens, which diverges only slightly. Each light source may ‘talk’ to substantially only one lens. The array of ‘beams’—one from each lens, may be parallel and generate a field of intense, parallel beams. By moving the relative position of the lens and source, the direction of the beam can be steered to emulate the movement of the sun. An observer looking into the light field may perceive a source that appears to be at infinity, and that appears to move if the observer does (the parallax effect). A color-tunable source can be used for emulating the solar spectrum and the color change throughout the day—e.g. a LED that has an emission close to that of a black-body and can be color-tuned along the black-body curve. 
       FIG.  2 A  illustrates an example interior luminaire system  190 . In particular embodiments the first light sources  202  and second light sources  203  may be arranged on a circuit board  220 . In particular embodiments, to provide the emulated sunlight, the luminaire  190  may also use one or more lenses  204  to collimate light from the first light sources  202 , thereby producing parallel rays of light. As depicted in  FIG.  2 A , the one or more lenses  204  may be arranged into a lens array  206 , which may be steerable. The lenses  204  should have a positive focal-length, but can be of any style, e.g. Fresnel lenses or conventional lenses, and can be single- or multi-element. 
     In particular embodiments, the interior luminaire system  190  can emit an intense, movable, substantially collimated beam of light that casts convincing shadows and exhibits a correct parallax effect, appearing to be at infinity. As an example, and not by way of limitation, the illuminance level emitted may be over 100,000 lux at midday. In particular embodiments, the electronic device  100  may be programmed to control the interior luminaire system  190  to change the direction of the beam throughout the day, mimicking the movement of the sun. In particular embodiments, the color of the emulated sunlight can also be changed over the course of the day, such that it is different at noon compared with early morning and late afternoon. In particular embodiments, the electronic device  100  can be programmed to subtly change the quality of emulated sunlight such that it is more diffused early and late in the day. Moreover, the electronic device  100  can be programmed to vary the angle and intensity of the emulated sunlight according to the time of day and the season. In particular embodiments, the spectrum of the emulated sun light can closely mimic the actual spectrum of sunlight. In addition, the luminaire system  190  may emit emulated skylight light from an artificial ‘sky’. In particular embodiments, the ‘skylight’ is not collimated, but instead is omnidirectional and provides diffuse illumination without casting substantial shadows. In particular embodiments, the electronic device  100  can be programmed to change the sky color change throughout day. In particular embodiments, the emulated skylight can mimic cloudy or overcast conditions. In particular embodiments, the interior luminaire system  190  can be window sized. As an example, and not by way of limitation, the interior luminaire system  190  can be a minimum of about 24″×36″ with a depth of no more than 6″ such that it can retrofit existing walls or ceilings. 
     As used herein, “sunlight” may refer to the light provided by the sun during the daytime hours. 
     As used herein, “skylight” may refer to the light provided by the sky during the daytime hours. Skylight generally appears blue, although its color may vary throughout the day. 
     As used herein, “daylight” may refer to the light provided by the sun and the sky during the daytime hours, daylight being comprised of sunlight and skylight. 
     As used herein, “light source” may refer to any artificial source of light. As an example, and not by way of limitation, a light-emitting diode (LED) is a light source. As another example, and not by way of limitation, a liquid-crystal display (LCD) is a light source. Although this disclosure describes particular artificial sources of light being used as light sources, this disclosure contemplates any suitable artificial sources of light being used as light sources. 
     Certain technical challenges exist for emulating natural daylight. One technical challenge may include generating a substantially collimated beam of light to emulate sunlight. One solution presented by the embodiments disclosed herein to address this challenge may be to use an array of light sources paired with an array of lenses to generate sets of parallel beams of light that together form a substantially collimated beam of light. Another technical challenge may include generating diffuse illumination that changes color over time to emulate natural skylight. One solution presented by the embodiments disclosed herein to address this challenge may be to use color-tunable LEDs and adjusting the color of the LEDs with computer programming. 
     Certain embodiments disclosed herein may provide one or more technical advantages. A technical advantage of the embodiments may include providing skylight that is not collimated, but instead is omnidirectional and provides diffuse illumination without casting shadows. Another technical advantage of the embodiments may include providing artificial sunlight that casts convincing shadows. Certain embodiments disclosed herein may provide none, some, or all of the above technical advantages. One or more other technical advantages may be readily apparent to one skilled in the art in view of the figures, descriptions, and claims of the present disclosure. 
     In particular embodiments, the interior luminaire system  190  may comprise an artificial sunlight system comprising one or more first light sources  202  and one or more first movable lenses  204  paired with the one or more of the first light sources  202 , respectively. As an example, and not by way of limitation, the one or more of the first light sources  202  may each comprise a color-tunable light emitting diode (LED). Each of these LEDs may be tunable to emulate a solar spectrum by changing, over a pre-determined time, a respective emission color of each LED within an approximate black-body curve. In particular embodiments, the electronic device  100  may be programmed to adjust the emission color of these LEDs to accurately match the diurnal changes in the solar color over the course of a day. As another example, and not by way of limitation, the first light sources  202  may comprise color-changing incandescent bulbs, which naturally emit a black-body spectrum, in combination with a color wheel to mimic the diurnal variation. Although this disclosure describes particular first light sources  202  being adjusted in a particular manner, this disclosure contemplates any suitable first light sources  202  being adjusted in any suitable manner. 
     In particular embodiments, each first light source  202  is configured to direct light only at the lens  204  with which it is respectively paired.  FIG.  2 A  depicts one method of directing the light from the first light sources  202  to the paired lenses  204 , which is by using a mechanical assembly E 3  that restricts the emission angle of the first light sources  202 . In particular embodiments, the mechanical assembly E 3  may be made of a transparent material and feature a reflective coating on its interior.  FIG.  2 B  illustrates a close-up view of a first light source  202  of  FIG.  2 A  emitting a cone of light E 5  onto a lens  204  of  FIG.  2 A  through restriction by the mechanical assembly E 4 . On the other hand,  FIG.  3    illustrates a first light source  202  comprising an integral lens that can restrict the emission angle of the first light source  202  so that it directs light only at the lens  204  with which it is paired. As an example, and not by way of limitation, an integral lens of a first light source may restrict an emission angle of that light source to +−15 degrees. In such embodiments, the one or more second light sources  203 , which may also be LEDs, may be operable to emit diffuse illumination through one or more optical scattering layers  230 . Although this disclosure describes restricting the first light sources  202  to direct light onto paired lenses  204  in particular ways, this disclosure contemplates restricting the first light sources  202  to direct light onto paired lenses  204  in any suitable ways. 
     In particular embodiments, the one or more first light sources  202  and the one or more second light sources  203  comprise color-tunable light emitting diodes (LEDs) positioned in an array.  FIG.  4    illustrates an array of first light sources  202  and second light sources  203 , wherein the first light sources  202  are positioned at the focal points of the lenses  204  and second light sources  203  are positioned outside of a focal area of the lenses. Although the depiction of  FIG.  4    is 2-dimensional, the center of the lenses  204  could be positioned approximately directly above the first light sources  202 . Thus, in particular embodiments, the lenses  204  of a lens array  206  could be positioned intersect above the second light sources  203 . In particular embodiments, the lenses  204  could therefore collimate the light of the first light sources  202 , thereby generating sets of parallel rays of light. On the other hand, in particular embodiments, because the light of the second light sources  203  would not be focused by the lenses  204 , the second light sources  203  could simultaneously generate diffuse illumination as the light of the second light sources  203  could pass through the lenses  204  at a wide variety of angles and be subsequently scattered in an omnidirectional emission pattern. Although this disclosure describes arranging first light sources  202  and second light sources  203  in particular patterns and arrays, this disclosure contemplates arranging first light sources  202  and second light sources  203  in any suitable arrangement. 
       FIG.  5    illustrates a second example interior luminaire system. As depicted in  FIG.  5   , in particular embodiments, the one or more first movable lenses  204  can be positioned in a lens array  206 , wherein the lens array  206  is steerable and can translate with at least two degrees of freedom, and wherein the artificial sunlight system is operable to move the substantially collimated beam of light by steering the lens array  206 . In particular embodiments, one or more adjustment mechanisms  216  may be operable to move each first light  202  source to a position relative to the first movable lens  204  with which it is paired that is at the focal point of that first movable lens  204 . As an example, and not by way of limitation, the adjustment mechanism  216  may be any mechanical apparatus driven using a driver board  212  and external controller  214 . In particular embodiments, allowing the first light sources  202  to be moved to the focal point of the lenses  204  allows the lenses  204  of the lens array  206  to collimate the light of the first light sources  202  into parallel rays of light that together form a movable beam of light. Although this disclosure describes using particular mechanical components to move the first light sources  202  to the focal points of the respective lenses  204 , this disclosure contemplates using any suitable mechanical components to move the first light sources  202  to the focal points of the respective lenses  204  in any suitable manner. 
       FIG.  6 A  illustrates a beam of light produced by a steerable lens array  206  before the lens array  206  has been steered. As depicted in  FIG.  6 A , each first light source-lens pair can be operable to generate a set of substantially parallel rays of light when each first light source  202  is positioned at approximately a focal point of the lens  204  with which it is paired. This may occur because each first light source  202  can shine on substantially only the lens  204  with which it is paired, as explained herein with more specificity. Thus, the interior luminaire system  190  can be operable to generate a substantially collimated beam of light comprising the sets of substantially parallel rays of light. However, in particular embodiments, the lenses  204  of the lens array  206  may also be steered laterally to move the substantially collimated beam of light laterally. Hence, the substantially collimated beam of light may be referred to as a “movable” beam of light.  FIG.  6 B  illustrates steering a beam of light by moving the lens array  206  laterally.  FIG.  6 A  and  FIG.  6 B  are simplified drawings intended to focus on the lateral steering aspects, but the other components of the luminaire system depicted in  FIG.  5    may also be present in particular embodiments.  FIG.  6 B  depicts how the lateral steering of the lens array  206  moves the light emitted from the first light sources  202  away from the focal points of the lenses  204 , thereby shifting the angle of the substantially collimated beam of light provided by the lens array  206 . However, in particular embodiments, steering the lens array  206  as such may cause some of the light of a first light source  202  to be directed at a lens  204  that it is not paired with, effectively introducing a level of “crosstalk.”  FIG.  7 A  illustrates this unintended crosstalk in a single-depth lens array  206  of lenses  204 . 
     Hence, in particular embodiments, the lens array  206  may further comprise one or more second movable lenses  205 , wherein each of the one or more second movable lenses  205  is paired with one of the one or more first movable lenses  204 , respectively, and wherein each of the one or more second movable lenses  205  is configured to receive light substantially only from the respective paired first movable lens  204 .  FIG.  7 B  illustrates how second movable lenses  205  can eliminate or reduce crosstalk. 
     Referring again to  FIG.  5   , in particular embodiments, the interior luminaire system  190  may comprise additional components such as a low-profile heat sink  208  and a diffusing layer  210 . In particular embodiments, the low-profile heat sink  208  can be used to absorb excess heat emitted by the interior luminaire system  190 . In particular embodiments, the diffusing layer  210  can be controlled by electronic device  100  which is programmed to make the emulated sunlight more diffuse at certain times of the day, mimicking natural sunlight. 
     In particular embodiments, the interior luminaire system  190  comprises a centralized light engine  802  that powers each of the one or more first light sources  202 , and wherein the centralized light engine  802  is tunable for color and luminescence.  FIG.  8    illustrates a third example interior luminaire system  190  using a centralized light-engine  802 . In particular embodiments, one or more optic fibers  804  may connect the centralized light-engine  802  to the one or more first light sources  202 . As an example, and not by way of limitation, the optics fibers  804  may be between 0.1 and 2.0 millimeters thick and the movable lens array  206  may be 10 to 20 millimeters from the first light sources  202 . In particular embodiments, an edge-lit diffuser  806  may be used as a second light source  203  to generate emulated skylight. As an example, and not by way of limitation, the edge-lit diffuser  806  may be similar to a panel as might be used in a television or a computer monitor. In particular embodiments, the edge-lit diffuser  806  may comprise edge-lighting LEDs that are color tunable to allow the color and intensity of the panel  806  to be adjusted. In particular embodiments, because the fiber  804  penetrations are spatially dilute, they do not interfere with the light diffusion. In particular embodiments, the optic fibers  806  penetrate the panel used for the sky effect and terminate at its front surface. In particular embodiments, the numerical aperture of the fibers  804  are selected so that the light emerges into a restricted emission cone (to match the numerical aperture of the lens  204 ), without the need of an additional restriction component. As an example, and not by way of limitation, the light-engine  802  may be a 30 W, color-tunable LED, or an incandescent source with a color-filter wheel. Although this disclosure describes incorporating a centralized light-engine  802  into an interior luminaire system  190  in a particular manner, this disclosure contemplates incorporating a centralized light-engine  802  into an interior luminaire system  190  in any suitable manner. 
       FIG.  9    illustrates a fourth example interior luminaire system using light pipes.  FIG.  9    illustrates an alternative approach to generating the emulated sunlight via an optic-fiber fan-out approach as shown and described in reference to  FIG.  8   . In particular embodiments, instead of a bundle of optic fibers  804  connecting a common light source  802  to a perforated diffuser panel  806 , this design uses a multitude of light pipes  810 , each light pipe  810  comprising one or more arms  808 . In particular embodiments, each light pipe has an independent LED  812  and is designed to split the light equally between several arms  808 . As an example, and not by way of limitation, each pipe  810  may have 10 arms  808 , but this value could range from 2-20 in various embodiments. Each arm  808  may be effectively the equivalent to one optic fiber  806  as depicted in and described in reference to  FIG.  8   . The light pipe  810  design of  FIG.  9    can provide potential benefits in terms of ease of manufacturing. Although this disclosure describes light pipes  810  into an interior luminaire system  190  in a particular manner, this disclosure contemplates incorporating light pipes  810  into an interior luminaire system  190  in any suitable manner. 
     In particular embodiments, the interior luminaire system  190  may comprise an artificial skylight system comprising one or more second light sources  203 , wherein each second light source  203  is operable to generate omnidirectional rays of light, and wherein the artificial skylight system is operable to generate diffuse illumination. As explained further above, the one or more second light sources  203  of the artificial sky-light system may comprise a transparent panel  806  comprising optical scattering sites and color-tunable light emitting diodes (LEDs), and wherein the color-tunable LEDs are operable to provide edge-illumination. Thus, in particular embodiments, the one or more second light sources may be color-tunable LEDs ( FIGS.  2 - 5   ) or a transparent panel  806  edge-lit by color-tunable LEDs ( FIGS.  8 - 9   ). But those embodiments are examples only. For example, in particular embodiments, the one or more second light sources  203  of the artificial skylight system comprise a transparent panel comprising a dilute concentration of one of blue fluorescent or blue phosphorescent particles, and wherein the particles are operable to be excited by edge illumination using ultraviolet (UV) light emitting diodes (LEDs). Moreover, in particular embodiments the one or more second light sources  203  of the artificial skylight system may comprise one or more tinted polymer-dispersed liquid crystal (PDLC) panels, and each of the one or more tinted PDLC panels may be operable to alter one or more characteristics of the diffuse illumination when a voltage is applied to that panel. 
     In particular embodiments, the disclosure systems and methods for realistically mimicking ‘real sunshine’ streaming into a window. Throughout the course of the day the scattering of real sunlight by the atmosphere may change, due to the azimuth of the sun (at lower angles the sunlight traverses a longer path through the atmosphere), or due to mist, clouds, smoke, rain, or other atmospheric conditions. Additionally, with increased atmospheric scattering, the ‘sharpness’ of shadows may change. In the case of very high scattering by clouds on an overcast day, the lighting becomes very diffused and the shadows may be absent. Particular embodiments include a method for mimicking these variable scattering effects. Particular embodiments include optical devices with scattering properties that can be changed under electrical control programmatically determined using electronic device  100 , including liquid-crystals (of several classes), including Polymer-Dispersed-Liquid-Crystals (PDLCs). In particular embodiments, color-tinted PDLCs can be used to modify the color of light to mimic sky-color changes throughout a day. In particular embodiments, an electrically controlled PDLC film can be placed on the outside of the interior luminaire system  190  to modify the emitted light, and to emulate variable atmospheric scattering. 
       FIG.  10 A  illustrates adjustable scattering with a white light source  1001  and a white PDLC film  1002  by varying an applied voltage.  FIG.  10 A  depicts that when light from a white light source  1001  hits a white PDLC film  1002  with a high voltage applied to the film  1002 , then it can produce highly scattered white light  1012 . However, when light from the white light source  1001  hits the white PDLC film  1002  with a moderate voltage less than the high voltage applied to the film  1002 , then it can produce moderately scattered white light  1013  which is scattered less than the highly scattered white light  1012 . Finally, when light from the white light source  1001  hits the white PDLC film  1002  with no voltage applied to the film  1002 , then it can produce white light which is not scattered at all  1014 . 
       FIG.  10 B  illustrates adjustable scattering with a white light source  1001  and a first color PDLC film  1022  by varying an applied voltage.  FIG.  10 B  depicts that when light from a white light source  1001  hits a first color PDLC film  1022  with a high voltage applied to the film  1022 , then it can produce highly scattered light of the first color  1032 . However, when light from the white light source  1001  hits the first color PDLC film  1022  with a moderate voltage less than the high voltage applied to the film  1022 , then it can produce moderately scattered light of the first color  1033  which is scattered less than the highly scattered light of the first color  1032 . The moderately scattered light of the first color  1033  may be a lighter shade of the first color than the highly scattered light of the first color  1032 . Finally, when light from the white light source  1001  hits the first color PDLC film  1022  with no voltage applied to the film  1022 , then it can produce white light which is not scattered at all  1014 . 
       FIG.  10 C  illustrates adjustable color control with a white light source  1001 , a first color PDLC film  1022 , and a second color PDLC film  1042  by varying applied voltages. When a voltage is applied to the first color PDLC film  1022 , but not the second color PDLC film  1042 , then light from the white light source  1001  is scattered when passing through the films and can emerge as scattered light of the first color  1052 . Conversely, when a voltage is applied to the second color PDLC film  1042 , but not the first color PDLC film  1022 , then light from the white light source  1001  is scattered when passing through the films and can emerge as scattered light of the second color  1053 . However, when no voltage is applied to either the first PDLC film  1022  or the second PDLC film  1042 , then light from the white light source  1001  is not scattered when passing through the films and can emerge as white light which is not scattered at all  1014 . Although this disclosure describes using PDLC films to adjust the level of scattering and color of light in particular ways, this disclosure contemplates using PDLC films to adjust the level of scattering and color of light in any suitable ways. 
     Further, in particular embodiments, by careful time synchronization for switching the PDLC and the ‘sun’ source, it is possible to scatter the emulated skylight, without scattering the emulated sunlight. Moreover, in particular embodiments, it is possible to use a blue-tinted PDLC to produce diffuse skylight light directly from the collimated emulated sunlight. Particular embodiments accomplish the foregoing using pulse width modulation (PWM), which may be understood as a sequence of square electrical pulses with a variable ON/OFF ratio. 
       FIG.  11 A  illustrates PWM control of a PDLC sheet to produce diffuse colored backlight and collimated sunlight with one light source. A duty cycle determined by electronic device  100  can change the relative brightness of collimated and scattered light, while using different voltages can adjust the color and scattering intensity.  FIG.  11    shows that when light from a white light source  1001  passes through a first color PDLC sheet with a voltage applied  1110 , then the output is scattered light of the first color  1111 .  FIG.  11    also shows that when light from a white light source  1001  passes through a first color PDLC sheet with no voltage applied  1120 , then the output is white light which is not scattered at all  1014 .  FIG.  11 B  illustrates a graph of a duty cycle corresponding to the output depicted in  FIG.  11 A . In  FIG.  11 B , the x-axis represents time, while the y-axis represents voltage. In the depicted example of  FIG.  11 A  and  FIG.  11 B , a voltage is applied to the PDLC at the times from T1 to T2, T3 to T4, and T5 to T6, but there is no voltage applied to the PDLC at the times from T2 to T3 and T4 to T5. Thus, in particular embodiments, the emulated sunlight and the emulated can be created by a single type of light source (e.g., the first light source  202 ), for example, using LEDs. The light  1111  that is generated by the first color PDLC sheet with a voltage applied  1110  is the emulated skylight, which can be diffuse and colored (e.g., blue). And the light  1014  that is generated by the first color PDLC sheet with no voltage applied  1120  is the emulated sunlight, which can be substantially collimated and white. In particular embodiments, as long as the frequency of the pulses is high enough, when the two types of emitted light,  1111 ,  1014  hit the human eye, there will be no perceptible irregularity and the viewer will perceive both the emulated skylight and the emulated sunlight. As an example, and not by way of limitation, the frequency of the pulses may be 60-100 Hz or more. Although this disclosure describes using PWM control of a PDLC sheet to produce diffuse colored backlight and collimated sunlight with one light source in a particular manner, this disclosure contemplates using PWM control of a PDLC sheet to produce diffuse colored backlight and collimated sunlight with one light source in any suitable manner. 
       FIG.  12    illustrates a fifth example interior luminaire system  190  using a steerable LED array with a collimator  1202 . Particular embodiments may include an edge-lit diffusion panel  806 , as well as a as a panel with a PDLC film  1204  for controllable scattering as described in reference to  FIGS.  10 - 11   . As depicted, particular embodiments can provide an oblique illumination into a room, without the viewer seeing the ‘sun’ that provides the emulated sunlight directly. In particular embodiments, the emulated ‘sun’ can be placed at the edge of the panel and be obliquely angled into a room. In particular embodiments, the source of the emulated sunlight can be LEDs or another first light source  202 . In particular embodiments, the ‘sun’ source can be a single element or an array of elements. In particular embodiments, the emulated sunlight can be collimated by using individual lenses, lens arrays, mirrors or total-internal-reflection (TIR) parabolic reflectors. In the depicted embodiment, the source consists of an array of LEDs each collimated by a plastic TIR reflector  1202 . In the depicted embodiment, the motion of the source can be achieved by a mechanical linkage—all the TIR reflectors can be ganged together so they move in parallel. In particular embodiments, the emulated sunlight can pass through a clear glass window  1206  after passing through the PDLC panel  1204 . In particular embodiments, the window may have features to give a parallax effect against the diffuser panel  806 . In particular embodiments, the diffuser panel  806  size may be larger than opening to help with the illusion of depth. Thus, in particular embodiments, an emulated ‘sun’ cannot be seen directly by a viewer, but a beam of sunshine may appear to illuminate surrounding walls. Although this disclosure describes providing an oblique window impression to a viewer in a particular manner, this disclosure contemplates producing an oblique window impression in any suitable manner. 
     As explained, further herein throughout this disclosure, the disclosure also provides various methods of using an interior luminaire system  190 . Wherein the one or more second light sources  203  of the artificial sky-light system comprise one or more tinted polymer-dispersed liquid crystal (PDLC) panels, one example method comprises applying a voltage to each of the one or more tinted PDLC panels to alter one or more characteristics of the diffuse illumination. Wherein each first light source  202  and each second light source  203  is tunable for color another example method comprises changing, over a pre-determined time, a respective emission color of each of the first light sources  202  within an approximate black-body curve to emulate a solar spectrum; and changing, over the pre-determined time, a respective emission color of each of the second light sources  203  to emulate skylight, wherein the emulated skylight comprises natural variations in skylight color caused by changing environmental conditions. Wherein the one or more first movable lenses  204  are positioned in an array  206 , another example method comprises moving, over a pre-determined time, the array  206  to change a direction of the substantially collimated beam of light to emulate a natural movement of the sun, wherein the array  206  is moved by translating a position of each first light source  202  relative to the lens  204  with which it is paired. Although this disclosure describes using an interior luminaire system  190  in particular manners, this disclosure contemplates using an interior luminaire system  190  in any suitable manner. 
       FIG.  13    illustrates is a flow diagram of a method  1300  for emulating natural daylight with an interior luminaire, in accordance with the presently disclosed embodiments. The method  1300  may be performed utilizing one or more integrated or external processing devices (e.g., electronic device  100 ) that may include hardware (e.g., a general purpose processor, a graphic processing unit (GPU), an application-specific integrated circuit (ASIC), a system-on-chip (SoC), a microcontroller, a field-programmable gate array (FPGA), a central processing unit (CPU), an application processor (AP), a visual processing unit (VPU), a neural processing unit (NPU), a neural decision processor (NDP), or any other processing device(s) that may be suitable for processing 2D and 3D image data, software (e.g., instructions running/executing on one or more processors), firmware (e.g., microcode), or some combination thereof. 
     The method  1300  may begin at step  1310  with providing a movable substantially collimated beam of light by an artificial sunlight system, wherein the artificial sunlight system comprises: one or more first light sources; and one or more first movable lenses paired with the one or more of the first light sources, respectively, wherein each first light source is configured to direct light only at the respective paired lens, and wherein each first light source-lens pair is operable to generate a set of substantially parallel rays of light when each first light source is positioned at approximately a focal point of the lens with which it is paired. The method  1300  may then continue at step  1320  with providing diffuse illumination by an artificial skylight system, wherein the artificial skylight system comprises one or more second light sources, and wherein each second light source is operable to generate omnidirectional rays of light. 
     Particular embodiments may repeat one or more steps of the method of  FIG.  13   , where appropriate. Although this disclosure describes and illustrates particular steps of the method of  FIG.  13    as occurring in a particular order, this disclosure contemplates any suitable steps of the method of  FIG.  13    occurring in any suitable order. Moreover, although this disclosure describes and illustrates an example method for emulating natural daylight with an interior luminaire including the particular steps of the method of  FIG.  13   , this disclosure contemplates any suitable method for emulating natural daylight with an interior luminaire including any suitable steps, which may include all, some, or none of the steps of the method of  FIG.  13   , where appropriate. Furthermore, although this disclosure describes and illustrates particular components, devices, or systems carrying out particular steps of the method of  FIG.  13   , this disclosure contemplates any suitable combination of any suitable components, devices, or systems carrying out any suitable steps of the method of  FIG.  13   . 
     Systems and Methods 
       FIG.  14    illustrates an example computer system  1400  that may be utilized to perform emulating natural daylight with an interior luminaire, in accordance with the presently disclosed embodiments. In particular embodiments, one or more computer systems  1400  perform one or more steps of one or more methods described or illustrated herein. In particular embodiments, one or more computer systems  1400  provide functionality described or illustrated herein. In particular embodiments, software running on one or more computer systems  1400  performs one or more steps of one or more methods described or illustrated herein or provides functionality described or illustrated herein. Particular embodiments include one or more portions of one or more computer systems  1400 . Herein, reference to a computer system may encompass a computing device, and vice versa, where appropriate. Moreover, reference to a computer system may encompass one or more computer systems, where appropriate. 
     This disclosure contemplates any suitable number of computer systems  1400 . This disclosure contemplates computer system  1400  taking any suitable physical form. As example and not by way of limitation, computer system  1400  may be an embedded computer system, a system-on-chip (SOC), a single-board computer system (SBC) (e.g., a computer-on-module (COM) or system-on-module (SOM)), a desktop computer system, a laptop or notebook computer system, an interactive kiosk, a mainframe, a mesh of computer systems, a mobile telephone, a personal digital assistant (PDA), a server, a tablet computer system, an augmented/virtual reality device, or a combination of two or more of these. Where appropriate, computer system  1400  may include one or more computer systems  1400 ; be unitary or distributed; span multiple locations; span multiple machines; span multiple data centers; or reside in a cloud, which may include one or more cloud components in one or more networks. 
     Where appropriate, one or more computer systems  1400  may perform without substantial spatial or temporal limitation one or more steps of one or more methods described or illustrated herein. As an example, and not by way of limitation, one or more computer systems  1400  may perform in real time or in batch mode one or more steps of one or more methods described or illustrated herein. One or more computer systems  1400  may perform at different times or at different locations one or more steps of one or more methods described or illustrated herein, where appropriate. 
     In particular embodiments, computer system  1400  includes a processor  1402 , memory  1404 , storage  1406 , an input/output (I/O) interface  1408 , a communication interface  1410 , and a bus  1412 . Although this disclosure describes and illustrates a particular computer system having a particular number of particular components in a particular arrangement, this disclosure contemplates any suitable computer system having any suitable number of any suitable components in any suitable arrangement. In particular embodiments, processor  1402  includes hardware for executing instructions, such as those making up a computer program. As an example, and not by way of limitation, to execute instructions, processor  1402  may retrieve (or fetch) the instructions from an internal register, an internal cache, memory  1404 , or storage  1406 ; decode and execute them; and then write one or more results to an internal register, an internal cache, memory  1404 , or storage  1406 . In particular embodiments, processor  1402  may include one or more internal caches for data, instructions, or addresses. This disclosure contemplates processor  1402  including any suitable number of any suitable internal caches, where appropriate. As an example, and not by way of limitation, processor  1402  may include one or more instruction caches, one or more data caches, and one or more translation lookaside buffers (TLBs). Instructions in the instruction caches may be copies of instructions in memory  1404  or storage  1406 , and the instruction caches may speed up retrieval of those instructions by processor  1402 . 
     Data in the data caches may be copies of data in memory  1404  or storage  1406  for instructions executing at processor  1402  to operate on; the results of previous instructions executed at processor  1402  for access by subsequent instructions executing at processor  1402  or for writing to memory  1404  or storage  1406 ; or other suitable data. The data caches may speed up read or write operations by processor  1402 . The TLBs may speed up virtual-address translation for processor  1402 . In particular embodiments, processor  1402  may include one or more internal registers for data, instructions, or addresses. This disclosure contemplates processor  1402  including any suitable number of any suitable internal registers, where appropriate. Where appropriate, processor  1402  may include one or more arithmetic logic units (ALUs); be a multi-core processor; or include one or more processors  1402 . Although this disclosure describes and illustrates a particular processor, this disclosure contemplates any suitable processor. 
     In particular embodiments, memory  1404  includes main memory for storing instructions for processor  1402  to execute or data for processor  1402  to operate on. As an example, and not by way of limitation, computer system  1400  may load instructions from storage  1406  or another source (such as, for example, another computer system  1400 ) to memory  1404 . Processor  1402  may then load the instructions from memory  1404  to an internal register or internal cache. To execute the instructions, processor  1402  may retrieve the instructions from the internal register or internal cache and decode them. During or after execution of the instructions, processor  1402  may write one or more results (which may be intermediate or final results) to the internal register or internal cache. Processor  1402  may then write one or more of those results to memory  1404 . In particular embodiments, processor  1402  executes only instructions in one or more internal registers or internal caches or in memory  1404  (as opposed to storage  1406  or elsewhere) and operates only on data in one or more internal registers or internal caches or in memory  1404  (as opposed to storage  1406  or elsewhere). 
     One or more memory buses (which may each include an address bus and a data bus) may couple processor  1402  to memory  1404 . Bus  1412  may include one or more memory buses, as described below. In particular embodiments, one or more memory management units (MMUs) reside between processor  1402  and memory  1404  and facilitate accesses to memory  1404  requested by processor  1402 . In particular embodiments, memory  1404  includes random access memory (RAM). This RAM may be volatile memory, where appropriate. Where appropriate, this RAM may be dynamic RAM (DRAM) or static RAM (SRAM). Moreover, where appropriate, this RAM may be single-ported or multi-ported RAM. This disclosure contemplates any suitable RAM. Memory  1404  may include one or more memory devices  1404 , where appropriate. Although this disclosure describes and illustrates particular memory, this disclosure contemplates any suitable memory. 
     In particular embodiments, storage  1406  includes mass storage for data or instructions. As an example, and not by way of limitation, storage  1406  may include a hard disk drive (HDD), a floppy disk drive, flash memory, an optical disc, a magneto-optical disc, magnetic tape, or a Universal Serial Bus (USB) drive or a combination of two or more of these. Storage  1406  may include removable or non-removable (or fixed) media, where appropriate. Storage  1406  may be internal or external to computer system  1400 , where appropriate. In particular embodiments, storage  1406  is non-volatile, solid-state memory. In particular embodiments, storage  1406  includes read-only memory (ROM). Where appropriate, this ROM may be mask-programmed ROM, programmable ROM (PROM), erasable PROM (EPROM), electrically erasable PROM (EEPROM), electrically alterable ROM (EAROM), or flash memory or a combination of two or more of these. This disclosure contemplates mass storage  1406  taking any suitable physical form. Storage  1406  may include one or more storage control units facilitating communication between processor  1402  and storage  1406 , where appropriate. Where appropriate, storage  1406  may include one or more storages  1406 . Although this disclosure describes and illustrates particular storage, this disclosure contemplates any suitable storage. 
     In particular embodiments, I/O interface  1408  includes hardware, software, or both, providing one or more interfaces for communication between computer system  1400  and one or more I/O devices. Computer system  1400  may include one or more of these I/O devices, where appropriate. One or more of these I/O devices may enable communication between a person and computer system  1400 . As an example, and not by way of limitation, an I/O device may include a keyboard, keypad, microphone, monitor, mouse, printer, scanner, speaker, still camera, stylus, tablet, touch screen, trackball, video camera, another suitable I/O device or a combination of two or more of these. An I/O device may include one or more sensors. This disclosure contemplates any suitable I/O devices and any suitable I/O interfaces  1406  for them. Where appropriate, I/O interface  1408  may include one or more device or software drivers enabling processor  1402  to drive one or more of these I/O devices. I/O interface  1408  may include one or more I/O interfaces  1406 , where appropriate. Although this disclosure describes and illustrates a particular I/O interface, this disclosure contemplates any suitable I/O interface. 
     In particular embodiments, communication interface  1410  includes hardware, software, or both providing one or more interfaces for communication (such as, for example, packet-based communication) between computer system  1400  and one or more other computer systems  1400  or one or more networks. As an example, and not by way of limitation, communication interface  1410  may include a network interface controller (NIC) or network adapter for communicating with an Ethernet or other wire-based network or a wireless NIC (WNIC) or wireless adapter for communicating with a wireless network, such as a WI-FI network. This disclosure contemplates any suitable network and any suitable communication interface  1410  for it. 
     As an example, and not by way of limitation, computer system  1400  may communicate with an ad hoc network, a personal area network (PAN), a local area network (LAN), a wide area network (WAN), a metropolitan area network (MAN), or one or more portions of the Internet or a combination of two or more of these. One or more portions of one or more of these networks may be wired or wireless. As an example, computer system  1400  may communicate with a wireless PAN (WPAN) (such as, for example, a BLUETOOTH WPAN), a WI-FI network, a WI-MAX network, a cellular telephone network (such as, for example, a Global System for Mobile Communications (GSM) network), or other suitable wireless network or a combination of two or more of these. Computer system  1400  may include any suitable communication interface  1410  for any of these networks, where appropriate. Communication interface  1410  may include one or more communication interfaces  1410 , where appropriate. Although this disclosure describes and illustrates a particular communication interface, this disclosure contemplates any suitable communication interface. 
     In particular embodiments, bus  1412  includes hardware, software, or both coupling components of computer system  1400  to each other. As an example, and not by way of limitation, bus  1412  may include an Accelerated Graphics Port (AGP) or other graphics bus, an Enhanced Industry Standard Architecture (EISA) bus, a front-side bus (FSB), a HYPERTRANSPORT (HT) interconnect, an Industry Standard Architecture (ISA) bus, an INFINIBAND interconnect, a low-pin-count (LPC) bus, a memory bus, a Micro Channel Architecture (MCA) bus, a Peripheral Component Interconnect (PCI) bus, a PCI-Express (PCIe) bus, a serial advanced technology attachment (SATA) bus, a Video Electronics Standards Association local (VLB) bus, or another suitable bus or a combination of two or more of these. Bus  1412  may include one or more buses  1412 , where appropriate. Although this disclosure describes and illustrates a particular bus, this disclosure contemplates any suitable bus or interconnect. 
     Herein, a computer-readable non-transitory storage medium or media may include one or more semiconductor-based or other integrated circuits (ICs) (such, as for example, field-programmable gate arrays (FPGAs) or application-specific ICs (ASICs)), hard disk drives (HDDs), hybrid hard drives (HHDs), optical discs, optical disc drives (ODDs), magneto-optical discs, magneto-optical drives, floppy diskettes, floppy disk drives (FDDs), magnetic tapes, solid-state drives (SSDs), RAM-drives, SECURE DIGITAL cards or drives, any other suitable computer-readable non-transitory storage media, or any suitable combination of two or more of these, where appropriate. A computer-readable non-transitory storage medium may be volatile, non-volatile, or a combination of volatile and non-volatile, where appropriate. 
     Miscellaneous 
     Herein, “or” is inclusive and not exclusive, unless expressly indicated otherwise or indicated otherwise by context. Therefore, herein, “A or B” means “A, B, or both,” unless expressly indicated otherwise or indicated otherwise by context. Moreover, “and” is both joint and several, unless expressly indicated otherwise or indicated otherwise by context. Therefore, herein, “A and B” means “A and B, jointly or severally,” unless expressly indicated otherwise or indicated otherwise by context. 
     Herein, “automatically” and its derivatives means “without human intervention,” unless expressly indicated otherwise or indicated otherwise by context. 
     The embodiments disclosed herein are only examples, and the scope of this disclosure is not limited to them. Embodiments according to the invention are in particular disclosed in the attached claims directed to a method, a storage medium, a system and a computer program product, wherein any feature mentioned in one claim category, e.g. method, can be claimed in another claim category, e.g. system, as well. The dependencies or references back in the attached claims are chosen for formal reasons only. However, any subject matter resulting from a deliberate reference back to any previous claims (in particular multiple dependencies) can be claimed as well, so that any combination of claims and the features thereof are disclosed and can be claimed regardless of the dependencies chosen in the attached claims. The subject-matter which can be claimed comprises not only the combinations of features as set out in the attached claims but also any other combination of features in the claims, wherein each feature mentioned in the claims can be combined with any other feature or combination of other features in the claims. Furthermore, any of the embodiments and features described or depicted herein can be claimed in a separate claim and/or in any combination with any embodiment or feature described or depicted herein or with any of the features of the attached claims. 
     The scope of this disclosure encompasses all changes, substitutions, variations, alterations, and modifications to the example embodiments described or illustrated herein that a person having ordinary skill in the art would comprehend. The scope of this disclosure is not limited to the example embodiments described or illustrated herein. Moreover, although this disclosure describes and illustrates respective embodiments herein as including particular components, elements, feature, functions, operations, or steps, any of these embodiments may include any combination or permutation of any of the components, elements, features, functions, operations, or steps described or illustrated anywhere herein that a person having ordinary skill in the art would comprehend. Furthermore, reference in the appended claims to an apparatus or system or a component of an apparatus or system being adapted to, arranged to, capable of, configured to, enabled to, operable to, or operative to perform a particular function encompasses that apparatus, system, component, whether or not it or that particular function is activated, turned on, or unlocked, as long as that apparatus, system, or component is so adapted, arranged, capable, configured, enabled, operable, or operative. Additionally, although this disclosure describes or illustrates particular embodiments as providing particular advantages, particular embodiments may provide none, some, or all of these advantages.