Ambient lighting improves sleep disorders, cognitive and / or neurological disorders.

Abstract

To provide a system and a method for providing ambient lighting that improves sleep quality, circadian rhythm, cognitive function, neurological disorders, depression, emotional states, heart rate variability, sympathetic and / or parasympathetic activity.SOLUTION: A lighting system for use in an ambient environment includes a light emitting device 11, and a controller coupled to the light emitting device. The light emitting device is configured to provide light that impinges on a subject in the ambient environment. The controller is configured to control the lighting device. The light provided by the light emitting device has at least 30% green light. A line extending from the light emitting device to the subject and a plane at the subject's eye level in the ambient environment form an angle of approximately 45 degrees. The light has a horizontal illuminance of about 2200 lux to about 2800 lux.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present disclosure provides a system and method for providing ambient lighting that improves sleep quality, circadian rhythm, cognitive function, neuropathy, depression, emotional state, heart rate variability, sympathetic activity, and / or parasympathetic activity.

Background Art

[0002] Light therapy is a method of treating seasonal affective disorder (SAD) and certain other conditions by exposure to artificial light. Light therapy is thought to affect mood and brain chemicals related to sleep while alleviating SAD symptoms. Using a light therapy box may also be helpful for other types of depression, sleep disorders, and other conditions. Light therapy is also known as bright light therapy or phototherapy. Multiple studies have shown that light intensity and the color / hue of light affect human health, and various health-related technologies based on lighting have been proposed.

[0003] Current light therapy cannot sufficiently improve sleep efficiency, affective disorders, and other psychological disorders. There is a continuing need for improvements in light therapy methods and devices that provide desirable lighting characteristics capable of overcoming the problems associated with conventional light therapy methods and devices.

Summary of the Invention

[0004] According to one exemplary embodiment of the present disclosure, an illumination system for use in an ambient environment includes a light-emitting device and a controller coupled to the light-emitting device. The light-emitting device is configured to provide light that impinges on a subject within the ambient environment. The controller is configured to control the light-emitting device. The light provided by the light-emitting device has at least 30% green light. A line extending from the light-emitting device to the subject forms an angle of about 45 degrees with a plane at the height of the subject's eyes within the ambient environment. The light has a horizontal illuminance of about 2200 lux to about 2800 lux.

[0005] According to another exemplary embodiment of the present disclosure, an ambient lighting system comprises a light-emitting device and a controller connected to the light-emitting device. The light-emitting device is configured to provide light to the ambient environment, and the light has at least 30% of the green light spectral component. The controller comprises a control module configured to control the light-emitting device, a sensing module configured to detect the illuminance value of the light provided by the light-emitting device, and a control interface that communicates with the control module.

[0006] According to another exemplary embodiment of the present disclosure, a method for providing ambient lighting to improve the quality of a subject's sleep includes providing light to the surrounding environment and exposing the subject to the light, wherein the proportion of blue-green light spectral components having wavelengths of about 450 nm to 580 nm is increased to at least 30%.

[0007] To further understand this disclosure, the following embodiments are provided with drawings to facilitate understanding of this disclosure, but the accompanying drawings are provided for reference and illustrative purposes only and do not limit the scope of this disclosure. [Brief explanation of the drawing]

[0008] [Figure 1] This is a block diagram schematically showing the configuration of a lighting system according to one embodiment of the present disclosure. [Figure 2] This is a schematic diagram of a lighting system in an ambient environment according to one embodiment of the present disclosure. [Figure 3] This is a schematic diagram of a light-emitting device according to one embodiment of the present disclosure. [Figure 4] This is a schematic diagram of a light-emitting device according to one embodiment of the present disclosure. [Figure 5] This is a schematic diagram of a light-emitting device according to one embodiment of the present disclosure. [Figure 6] This is a schematic diagram of a light-emitting device according to one embodiment of the present disclosure. [Figure 7]This flowchart illustrates the operation of an exemplary method for providing ambient lighting that improves sleep disorders, cognitive and / or neurological disorders in subjects. [Figure 8] This is a flowchart for recruiting participants. [Figure 9A] This figure shows the lighting model for the experimental group. [Figure 9B] This figure shows the illumination model for the comparison group. [Figure 10A] This figure shows the results of the experimental and control groups at various points in time regarding sleep efficiency. [Figure 10B] This figure shows the results of the experimental and control groups regarding sleep duration at various points in time. [Figure 10C] This figure shows the results for the experimental and control groups at various points in time regarding wakefulness. [Figure 10D] This figure shows the results for the experimental and control groups regarding the number of nighttime awakenings at various points in time. [Figure 11A] This figure shows the results of the experimental and control groups at various points in time regarding sleep onset. [Figure 11B] This figure shows the results for the experimental and control groups at various points in time regarding sleep offset. [Figure 12] This figure shows that the experimental group showed a significant improvement in NPI from baseline to week 5 and week 9 compared to the control group (Wald's test = 12.59, P < 0.001; Wald's test = 10.39, P = 0.001). [Figure 13] This figure shows that the experimental group showed a significant improvement in MMSE scores from baseline to week 5 and week 9 compared to the control group (Wald's test = 7.2, P < 0.007; Wald's test = 3.9, P = 0.04). [Figure 14A] This figure shows the results of the experimental and control groups regarding emotional states at various points in time. [Figure 14B] This figure shows the results of the experimental and control groups regarding psychiatric symptoms at various points in time. [Figure 14C]It is a diagram showing the results of the experimental group and the comparison group at various time points regarding motor disorders. [Figure 14D] It is a diagram showing the results of the experimental group and the comparison group at various time points regarding sleep disorders. [Figure 15A] It is a diagram showing the results of the experimental group and the comparison group at various time points regarding orientation. [Figure 15B] It is a diagram showing the results of the experimental group and the comparison group at various time points regarding memorization. [Figure 15C] It is a diagram showing the results of the experimental group and the comparison group at various time points regarding attention and calculation. [Figure 15D] It is a diagram showing the results of the experimental group and the comparison group at various time points regarding reproduction. [Figure 15E] It is a diagram showing the results of the experimental group and the comparison group at various time points regarding language and visuospatial construction.

Mode for Carrying Out the Invention

[0009] In the following detailed description, for purposes of explanation and not limitation, exemplary embodiments are described that disclose specific details in order to provide a thorough understanding of the various principles and aspects. However, it will be apparent to those skilled in the art who enjoy the benefits of this disclosure that the claimed subject matter can be practiced in other embodiments that depart from the specific details disclosed herein. Further, descriptions of known devices, methods, and materials may be omitted so as not to obscure the description of the various principles described herein. Finally, where applicable, like reference numerals always refer to like elements.

[0010] Terms not specifically defined herein should be understood according to the meanings that would be given to them by those skilled in the art in light of this disclosure and the context. However, as used herein, unless otherwise specified, the following terms have the meanings indicated according to the following conventions.

[0011] The terms "disease" and "disorder" in this specification can be used interchangeably.

[0012] The terms “subject,” “individual,” and “patient” are interchangeable herein and typically refer to mammals, and in certain embodiments, to humans or non-human primates.

[0013] The term "lux" refers to a unit of light measurement that takes area into account, and represents light intensity. Lux is effective for measuring the amount of light output in a given area, with 1 lux equal to 1 lumen per square meter. Lux is the best measure of the brightness of light rays seen by humans. Lux also determines the magnitude of light intensity as it travels a certain distance.

[0014] The terms "light source" and "illumination source" are used interchangeably and typically refer to a device that provides light within the visible spectrum for human use.

[0015] When humans are exposed to light, a signal is sent to the body, releasing cortisol, a hormone necessary for combating stress. The hormone cortisol also alerts the brain, thereby determining mood. Lack of light can affect the body's circadian rhythm, which is the 24-hour sleep / wake cycle. Exposure to sunlight stimulates the hypothalamus in the brain, which helps animals regulate their circadian rhythm. If the circadian rhythm is dysregulated, the brain may produce too much melatonin and too little serotonin. So, in short, lack of light makes humans feel tired and unhappy.

[0016] Phototherapy has long been recognized as a treatment option for conditions such as depression and insomnia. While phototherapy is recognized as effective in treating a wide variety of indications, it is still not fully utilized as a treatment. Appropriate application of phototherapy to patients in need requires the selection of multiple variables and repeated monitoring throughout the treatment process. These parameters include the wavelength, energy density, power density, and timing of the applied light, as well as any relevant patient-specific parameters. Inappropriate parameter selection can lead to reduced treatment effectiveness or adverse treatment outcomes.

[0017] This disclosure has surprisingly found that ambient lighting provided by at least 30% or 30% green light or the green spectral component of light can improve sleep disorders, cognitive and / or neurological disorders without affecting vision. Therefore, a lighting system and method for providing ambient lighting have been developed.

[0018] Figure 1 is a schematic block diagram showing the configuration of a lighting system 1 according to one embodiment of the present disclosure. As shown in Figure 1, the lighting system may include a light-emitting device 11, an adjustment mechanism 13 connected to the light-emitting device 11, a controller 15 coupled to the light-emitting device 11 and the adjustment mechanism 13, and a power supply unit 17 electrically connected to the light-emitting device 11.

[0019] The light-emitting device 11 may include at least one light source. The light source is an object that provides light to enhance visibility. There are many different types of light-emitting devices 11, which provide different amounts and qualities of light. The light-emitting device 11 can provide a light source that provides at least 20% (preferably at least 30%) of green light or the green spectral component of light. The percentage of green light can be calculated by defining the area of ​​the spectrum of the green region relative to the whole spectrum. In some embodiments of this disclosure, the light-emitting device may be a tungsten lamp, a halogen lamp, a xenon arc lamp, a CP lamp, or a light-emitting diode (LED). In some embodiments of this disclosure, the light-emitting device 11 contains at least 20%, 30%, 40%, 50%, or 60% of green light or the green spectral component of light. Preferably, the light-emitting device 11 may contain about 20% to about 60%, about 30% to about 60%, or about 30% to about 50% of green light or the green spectral component of light.

[0020] In some embodiments of this disclosure, the light-emitting device 11 includes multiple wavelengths of green light or the green spectral component of light. Examples of wavelengths include, but are not limited to, about 480 nm to about 580 nm, or about 500 nm to about 535 nm, or about 500 nm to about 530 nm, or about 510 nm to about 550 nm, or about 510 nm to about 540 nm, or about 510 nm to about 530 nm, or about 520 nm to about 550 nm, or about 520 nm to about 540 nm, or about 530 nm to about 580 nm. In some embodiments of this disclosure, the wavelength of green light or the green spectral component of light is in the range of about 480 nm to 580 nm. In some embodiments of this disclosure, the light-emitting device includes blue-green light having wavelengths of about 450 nm to 580 nm.

[0021] To achieve favorable improvements in phototherapy, light-emitting devices can provide multiple parameters, either individually or in combination, in addition to green light.

[0022] As described above, the light-emitting device 11 can provide at least 20% (preferably 30%) of green light or the green spectral component of light. In some embodiments of this disclosure, the light-emitting device provides at least 30% of green light or the green spectral component of light, and the green light spectral component or green spectral component (or blue-green light spectral component or blue-green spectral component) has wavelengths of about 450 nm to about 580 nm. In some embodiments of this disclosure, the green light spectral component or green spectral component has wavelengths of about 480 nm to about 580 nm. In some embodiments of this disclosure, such a ratio of green light or the green spectral component of light can be achieved by increasing the green light or the green spectral component of light provided by the light-emitting device 11. In some embodiments of this disclosure, such a ratio of green light or the green spectral component of light can be achieved by decreasing the blue light or the blue spectral component of light provided by the light-emitting device 11. In some embodiments of this disclosure, the proportion of blue light or blue light spectral components having wavelengths of approximately 415 nm to 460 nm is reduced, while the proportion of blue light or blue light spectral components having wavelengths of approximately 465 nm to 490 nm is maintained. In some embodiments of this disclosure, the optical spectrum of the light provided by the light-emitting device 11 is the same as or similar to the solar spectrum.

[0023] Furthermore, the color fidelity (Rf) / color gamut (Rg) of the light provided by the light-emitting device 11 may be greater than 90 / 95.

[0024] Illuminance is a measure of how much light illuminates a surface. Illuminance is the amount of light that strikes a vertical surface or plane. Illuminance is measured in units of "lux" on a vertically positioned virtual surface. The vertical direction can be various, such as perpendicular to the camera or perpendicular to the audience. The light-emitting device 11 can provide light having a total illuminance and / or illuminance of green light or green spectral components of at least about 2000 lux, about 2200 lux, about 2500 lux, about 2800 lux, about 3000 lux, about 3600 lux, about 4000 lux, about 4400 lux, or about 4800 lux. Preferably, the total illuminance and / or illuminance of green light or green spectral components is measured at the height level of the subject's ear, eye, or top of head. In some embodiments of this disclosure, illuminance includes vertical illuminance, which is the amount of light hitting a horizontal surface or plane at the height level of the subject's ears, eyes, or the top of their head, and horizontal illuminance, which is the amount of light hitting a vertical surface or plane at the height level of the subject's ears, eyes, or the top of their head. In some embodiments of this disclosure, the light-emitting device 11 can provide light having a total vertical illuminance and / or vertical illuminance of green light or a green spectral component of at least about 2000 lux, about 2500 lux, about 3000 lux, about 3600 lux, about 4000 lux, about 4400 lux, or about 4800 lux. In some embodiments of this disclosure, the light-emitting device 11 can provide light having a total horizontal illuminance and / or horizontal illuminance of green light or green spectral components of at least 15 lux, about 300 lux, about 350 lux, about 400 lux, about 500 lux, about 750 lux, about 1000 lux, about 1500 lux, about 2000 lux, about 2200 lux, about 2500 lux, or about 2800 lux.

[0025] The color rendering index (CRI) is a quantitative measure of a light source's ability to faithfully reproduce the colors of various objects compared to an ideal or natural light source. In some embodiments of this disclosure, the color rendering index (%) of the light-emitting device 11 is higher than approximately 70, approximately 75, approximately 80, approximately 85, approximately 90, or approximately 95. In some embodiments of this disclosure, the CRI of the light-emitting device 11 is in the range of approximately 70 to approximately 98, approximately 70 to approximately 95, approximately 70 to approximately 90, approximately 70 to approximately 85, approximately 70 to approximately 80, approximately 75 to approximately 98, approximately 75 to approximately 95, approximately 75 to approximately 85, approximately 80 to approximately 98, approximately 80 to approximately 95, approximately 80 to approximately 80, approximately 80 to approximately 85, approximately 85 to approximately 98, approximately 85 to approximately 95, approximately 85 to approximately 90, or approximately 90 to approximately 98.

[0026] The color quality scale (CQS) is a color rendering index (a quantitative measure of a light source's ability to reproduce the colors of illuminated objects). In some embodiments of this disclosure, the CQS of the light-emitting device 11 is in the range of approximately 20 to approximately 90, approximately 65 to approximately 95, approximately 65 to approximately 90, approximately 65 to approximately 85, approximately 65 to approximately 80, approximately 65 to approximately 75, approximately 70 to approximately 98, approximately 70 to approximately 95, approximately 70 to approximately 90, approximately 70 to approximately 85, approximately 70 to approximately 80, approximately 75 to approximately 98, approximately 75 to approximately 90, approximately 75 to approximately 85, approximately 80 to approximately 98, approximately 80 to approximately 90, approximately 85 to approximately 98, or approximately 85 to approximately 95.

[0027] Color temperature is a way of describing the appearance of light provided by a light source. It is measured in Kelvin degrees (K) on a scale of 1000 to 10000. In some embodiments of this disclosure, the light-emitting device 11 provides a color temperature of at least 1850K, at least 2500K, at least 2800K, at least 3000K, at least 3500K, at least 5000K, at least 5500K, at least 6500K, at least 8000K, or at least 10000K. Preferably, the color temperature ranges from about 1850K to about 2500K to about 2800K to about 3000K to about 3500K to about 5000K, or from about 5500K to about 10000K, or to about 8000K, or to about 6500K. In some embodiments, the light source provides a color temperature of approximately 1850K, approximately 2500K, approximately 2800K, approximately 3000K, approximately 3500K, approximately 5000K, approximately 5500K, approximately 6500K, approximately 8000K, or approximately 10000K.

[0028] Referring to Figure 1, the adjustment mechanism 13 is connected to the light-emitting device 11. The adjustment mechanism 13 is configured to move the light-emitting device 11. In some embodiments of this disclosure, the adjustment mechanism 13 is configured to change the height of the light-emitting device 11. In some embodiments of this disclosure, the adjustment mechanism 13 is configured to change the elevation angle of the light-emitting device 11.

[0029] As shown in Figure 1, the controller 15 is coupled to the light-emitting device 11 and / or to the adjustment mechanism 13. The controller 15 can control the operation of the entire light-emitting device 11.

[0030] In some embodiments of this disclosure, the controller 15 comprises a control module 151, a detection module 153, and a control interface 155. In some embodiments of this disclosure, the control module 151 may be implemented as a processor, controller, arithmetic logic unit (ALU), digital signal processor, microcomputer, field-programmable gate array (FPGA), programmable logic unit (PLU), microprocessor, etc. The control module 151 may be coupled to the light-emitting device 11. That is, the control module 151 can control the light-emitting operation of the light-emitting device 11. The control module 151 can adjust at least one of the color temperature, brightness, and color of the light emitted from the light-emitting device 11. The control module 151 can control the light-emitting operation of the light-emitting device 11 in response to information or signals detected by the detection module 153. The control module 151 may also be implemented to control the light-emitting operation of the light-emitting device 11 in response to user switch operation. In some embodiments of this disclosure, the control module 151 is a wall-mounted dimmer. Furthermore, the control module 151 may be implemented to control the light emission operation of the light-emitting device 11 by control signals or information input from other devices such as the control interface 155.

[0031] The detection module 153 may be coupled to and / or communicate with the control module 151 and / or the control interface 155. Examples of sensors for the detection module 153 include infrared sensors, distance sensors, gyro sensors, gravity sensors, position sensors, proximity sensors, illuminance sensors or RGB sensors (illuminance sensors), magnetic sensors, inertial sensors, touch sensors, and microphones. The detection module can also detect the attitude and position of the light-emitting device 11, the surrounding environment of the light-emitting device 11, or the user's movements. The detection module 153 can transfer acquired data and / or information to the control module 151, which can then automatically control the light-emitting operation of the light-emitting device 11 based on the data or information from the detection module 153. The detection module 153 can also transfer acquired data and / or information to the control interface 155, which the user can read through the control interface 155. The detection module 153 can also directly display acquired data and / or information to the user.

[0032] The control interface 155 may be coupled to and / or communicate with the control module 151 and / or the detection module 153. The control interface 155 may also be a remote control unit such as a mobile device having control software. The control interface 155 may include a Bluetooth communication module, a BLE (Bluetooth Low Energy) communication module, a Near Field Communication unit, a WLAN (Wi-Fi) communication module, a Zigbee communication module, an infrared (IrDA) data-related communication module, a WFD (Wi-Fi Direct) communication module, a UWB (Ultra-Wideband) communication module, or a communication module such as an Ant+ communication module. Furthermore, the control interface 155 can send commands to the control module 151 to control the light-emitting device 11 and / or the adjustment mechanism 13. The control interface 155 can receive data and / or information from the detection module 153. That is, the light-emitting device 11 can receive control commands or various information related to the operation of the light-emitting device 11 from the control interface 155. In addition, status information, operation information, or information collected by the detection module 153 of the light-emitting device 11 may be provided to the control interface 155.

[0033] Furthermore, the controller 15 may be coupled to or communicate with the adjustment mechanism 13. In some embodiments of this disclosure, the control module 151 of the controller 15 communicates with the adjustment mechanism. That is, the control module 151 can drive the adjustment mechanism 13 to move the light-emitting device 11 according to information or signals detected by the sensing module 153. Alternatively, a user can control the adjustment mechanism 13 to move the light-emitting device 11 via the control interface 155 of the controller 15.

[0034] Furthermore, a power supply unit 17 may be electrically connected to the light-emitting device 11. The power supply unit 17 is configured to supply operating power to the light-emitting device 11. In some embodiments of this disclosure, the power supply unit 17 may include a battery. In some embodiments of this disclosure, the power supply unit 17 may be connected to the light-emitting device 11 via a power cable. In some embodiments of this disclosure, the power supply unit 17 may include a waterproof, adjustable power supply.

[0035] Figure 2 is a schematic diagram of a lighting system 1 in an ambient environment 10 according to one embodiment of the present disclosure. As shown in Figure 2, the light-emitting device 11 is positioned within the ambient environment 10 and provides light within the ambient environment 10. In some embodiments of the present disclosure, the ambient light within the ambient environment 10 includes light provided by the light-emitting device 11. In some embodiments of the present disclosure, the ambient light within the ambient environment includes light that is a mixture of light provided by the light-emitting device and the intrinsic light in the ambient environment 10.

[0036] The subject 100 is in the surrounding environment 10 and is exposed to ambient light. That is, light emitted from the light-emitting device 11 may strike the subject 100. In some embodiments of the present disclosure, the subject 100 receives such light while seated. In some embodiments of the present disclosure, the subject 100 receives such light while standing. In some embodiments of the present disclosure, the subject 100 receives such light while lying down. In some embodiments of the present disclosure, the light-emitting device 11 can provide light having a total vertical illuminance L1 and / or vertical illuminance L1 of green light or green spectral components of at least about 2000 lux, about 2500 lux, about 3000 lux, about 3600 lux, about 4000 lux, about 4400 lux, or about 4800 lux. Subject 100 may be exposed to ambient light having a vertical illuminance L1 of at least about 2000 lux, about 2500 lux, about 3000 lux, about 3600 lux, about 4000 lux, about 4400 lux, or about 4800 lux. In some embodiments of the present disclosure, the light-emitting device 11 can provide light having a total vertical illuminance L1 and / or vertical illuminance L1 of green light or green spectral components of about 4000 lux to about 4400 lux. Subject 100 may be exposed to ambient light having a vertical illuminance L1 of about 4000 lux to about 4400 lux. In some embodiments of the present disclosure, the light-emitting device 11 can provide light having a total vertical illuminance L1 and / or vertical illuminance L1 of green light or green spectral components of about 3600 lux to about 4800 lux. Subject 100 may be exposed to ambient light having a vertical illuminance L1 of approximately 3600 lux to approximately 4800 lux. In some embodiments, the total vertical illuminance L1 and / or vertical illuminance L1 of green light or green spectral components is measured at the height level of subject 100's ear, eye, or head. That is, the total vertical illuminance L1 may be the amount of light hitting a horizontal surface or horizontal plane P1 at the height level of subject 100's ear, eye, or head. The vertical illuminance L1 of green light or green spectral components may be the amount of green light hitting a horizontal surface or horizontal plane P1 at the height level of subject 100's ear, eye, or head.

[0037] In some embodiments of this disclosure, the light-emitting device 11 can provide light having a total horizontal illuminance and / or horizontal illuminance L2 of at least about 15 lux, about 300 lux, about 350 lux, about 400 lux, about 500 lux, about 750 lux, about 1000 lux, about 1500 lux, about 2000 lux, about 2200 lux, about 2500 lux, or about 2800 lux of green light or green spectral components. A subject 100 may be exposed to ambient light having a horizontal illuminance L2 of at least 15 lux, about 300 lux, about 350 lux, about 400 lux, about 500 lux, about 750 lux, about 1000 lux, about 1500 lux, about 2000 lux, about 2200 lux, about 2500 lux, or about 2800 lux. In some embodiments of this disclosure, the light-emitting device 11 can provide light having a total horizontal illuminance L2 and / or horizontal illuminance L2 of green light or green spectral components of about 2200 lux to about 2800 lux. The subject 100 may be exposed to ambient light having a horizontal illuminance L2 of about 2200 lux to about 2800 lux. In some embodiments, the total horizontal illuminance L2 and / or horizontal illuminance L2 of green light or green spectral components is measured at the height level of the subject 100's ear, eye, or head. That is, the total horizontal illuminance L2 may be the amount of light hitting a vertical surface or vertical plane P2 at the height level of the subject 100's ear, eye, or head. The horizontal illuminance L2 of green light or green spectral components may be the amount of green light hitting a vertical surface or vertical plane P2 at the height level of the subject 100's ear, eye, or head.

[0038] In some embodiments of this disclosure, the light-emitting device 11 is configured such that the angle formed between the light-emitting device 11 and the subject 100 is greater than about 30 degrees. In some embodiments of this disclosure, the angle is formed between the light-emitting device and the height level of the subject 100's ear, eye, or top of head. In some embodiments, the angle is in the range of about 30 degrees, or about 40 degrees, or about 45 degrees, up to about 90 degrees, or about 80 degrees, or about 60 degrees. That is, the light emitted from the light-emitting device 11 to the subject 100 and the plane P1 at the eye level of the subject 100 form an angle, and this angle is in the range of about 30 degrees, or about 40 degrees, or about 45 degrees, up to about 90 degrees, or about 80 degrees, or about 60 degrees. In some embodiments of this disclosure, the angle between the light emitted from the light-emitting device 11 to the subject 100 and the plane P1 at the eye level of the subject 100 is about 45 degrees. Therefore, the light from the light-emitting device 11 to the subject 100 includes an optical axis, and the optical axis and the plane P1 at the eye level of the subject 100 form an angle α, the angle α ranging from about 30 degrees, or about 40 degrees, or about 45 degrees to about 90 degrees, or about 80 degrees, or about 60 degrees. In some embodiments of this disclosure, the angle α between the optical axis of the light from the light-emitting device 11 to the subject 100 and the plane P1 at the eye level of the subject 100 is about 45 degrees. In other words, the line X1 extending from the light-emitting device 11 to the subject 100 and the plane P1 at the eye level of the subject 100 form an angle α, the angle α ranging from about 30 degrees, or about 40 degrees, or about 45 degrees to about 90 degrees, or about 80 degrees, or about 60 degrees. In some embodiments of this disclosure, the angle α between a line X1 extending from the light-emitting device 11 to the subject 100 and a plane P1 at the eye level of the subject 100 is approximately 45 degrees. The line X1 extending from the light-emitting device 11 to the subject 100 may also include the optical axis of the light emitted from the light-emitting device 11.

[0039] As shown in Figure 2, the adjustment mechanism 13 may include a lifting platform 131 and a head 132. The light-emitting device 11 may be mounted on the head 132, and the head 132 may be connected to the lifting platform 131. The head 132 is configured to change the elevation angle of the light-emitting device 11. The lifting platform 131 is configured to change the height of the light-emitting device. That is, the illuminance of the light provided by the light-emitting device 11 and / or the optical axis of the light provided by the light-emitting device 11 can be changed by the adjustment mechanism 13.

[0040] Furthermore, as shown in Figure 2, the detection module 153 may be positioned adjacent to the ear, eye, or top of the head of the subject 100. In some embodiments of this disclosure, the detection module 153 is configured to detect the total vertical illuminance L1 and / or horizontal illuminance L2 of green light or green spectral components at the height level of the ear, eye, or top of the head of the subject 100.

[0041] The control module 151 may be connected to or communicate with the adjustment mechanism 13 and the light-emitting device 11. The control module 151 can change the position of the light-emitting device 11 by driving the adjustment mechanism 13 and control the light-emitting operation of the light-emitting device 11. Thus, the angle between the optical axis of the light and the plane P1 at the eye level of the subject 100, and the illuminance of the green light or green spectral component at the ear, eye, or top of the head of the subject 100 can be changed by the control module 151. In some embodiments of the present disclosure, the control module 151 is connected to or communicates with the detection module 153, and the control module 151 drives the adjustment mechanism 13 and / or controls the light-emitting device 11 according to information / data from the detection module 153. In some embodiments of the present disclosure, the control module 151 is connected to or communicates with the control interface 155, and the control module 151 drives the adjustment mechanism 13 and / or controls the light-emitting device 11 according to commands from the control interface 155. In some embodiments of this disclosure, the control interface 155 is connected to or communicates with the detection module 153, and the subject 100 can read information / data collected by the detection module 153 through the control interface 155.

[0042] Figure 3 is a schematic diagram of a light-emitting device 2 according to one embodiment of the present disclosure. The light-emitting device 2 is identical or similar to the light-emitting device 11. The light-emitting device 2 may include a group of red light LEDs 21, a group of green light LEDs 22, and a group of blue light LEDs 23. The red light LED group 21 may include a plurality of red light LED units 210. The green light LED group 22 may include a plurality of green light LED units 220. The blue light LED group 23 may include a plurality of blue light LED units 230. The number of red light LED units 210 is N. The number of green light LED units 220 is M. The number of blue light LED units 230 is L. Also, N, M, and L are positive integers. In some embodiments of the present disclosure, 0.2 ≤ M / (N + M + L) ≤ 0.6. That is, the light emitted from the light-emitting device 2 may contain 20% to 60% green light or the green spectral component of light. In some embodiments of this disclosure, 0.25 ≤ M / (N+M+L) ≤ 0.45. That is, the light emitted from the light-emitting device 2 may contain 25% to 45% green light or the green spectral component of the light. In some embodiments of this disclosure, 0.4 ≤ M / (N+M+L). That is, the light emitted by the light-emitting device 2 may contain at least 40% green light or the green spectral component of the light. In some embodiments of this disclosure, the size of the light-emitting device 2 is 300 mm × 1200 mm. In some embodiments of this disclosure, the size of the light-emitting device 2 is 600 mm × 600 mm.

[0043] Figure 4 is a schematic diagram of a light-emitting device 3 according to one embodiment of the present disclosure. The light-emitting device 3 is identical or similar to the light-emitting device 11. The light-emitting device 3 may include an optical filter 30 having a red light transition region 31, a green light transition region 32, and a blue light transition region 33. The area of ​​the red light transition region 31 is P. The area of ​​the green light transition region 32 is Q. The area of ​​the blue light transition region 33 is R. Also, P, Q, and R are positive integers. In some embodiments of the present disclosure, 0.2 ≤ Q / (P+Q+R) ≤ 0.6. That is, the light emitted from the light-emitting device 3 may contain 20% to 60% green light or the green spectral component of the light. In some embodiments of the present disclosure, 0.25 ≤ Q / (P+Q+R) ≤ 0.45. That is, the light emitted from the light-emitting device 3 may contain 25% to 45% green light or the green spectral component of the light. In some embodiments of this disclosure, 0.4 ≤ Q / (P + Q + R). That is, the light emitted by the light-emitting device 3 may contain at least 40% green light or the green spectral component of the light. In some embodiments of this disclosure, the size of the light-emitting device 3 is 300 mm × 1200 mm. In some embodiments of this disclosure, the size of the light-emitting device 3 is 600 mm × 600 mm.

[0044] Figure 5 is a schematic diagram of a light-emitting device 4 according to one embodiment of the present disclosure. The light-emitting device 4 is identical or similar to the light-emitting device 11. The light-emitting device 4 may include brick lamps 41 and 42. Brick lamp 41 may include an electrical connection 410. Brick lamp 42 may include an electrical connection 420. Brick lamps 41 and 42 can be electrically connected to each other via the electrical connection 410 and / or 420. That is, the brick lamps 41 and 42 are arranged in a tile-like configuration. Therefore, the brick lamps 41 and 42 can be used in various styles of ambient environments.

[0045] Figure 6 is a schematic diagram of a light-emitting device 5 according to one embodiment of the present disclosure. The light-emitting device 5 is identical or similar to the light-emitting device 11. The light-emitting device 5 may include a light source 51 and a diffuser mounting fixture 53. The diffuser mounting fixture 53 is configured to diffuse the light emitted from the light source 51.

[0046] Figure 7 is a flowchart illustrating the exemplary operation of Method 6, which provides ambient lighting to improve sleep disorders, cognitive and / or neurological disorders in subjects. As mentioned above, phototherapy is a method of treating seasonal affective disorder (SAD) and certain other conditions by exposure to artificial light. Phototherapy is thought to affect brain chemicals related to mood and sleep while alleviating SAD symptoms. Method 6 relates to the operation of providing a lighting system to the surrounding environment in which phototherapy can be performed.

[0047] In operation 61, a light-emitting device identical or similar to the light-emitting device 11 is provided in the surrounding environment. For example, the light-emitting device may provide a light source that provides at least 20% (preferably at least 30%) of green light or the green spectral component of light. The percentage of green light can be calculated by defining the area of ​​the spectrum of the green region relative to the whole spectrum, and the light-emitting device provides a color temperature of at least 1850K, at least 2500K, at least 2800K, at least 3000K, at least 3500K, at least 5000K, at least 5500K, at least 6500K, at least 8000K, or at least 10000K.

[0048] In operation 63, the light-emitting device is controlled and / or adjusted so that the optical axis of the light emitted from the light-emitting device and / or the illuminance of the light provided by the light-emitting device satisfy predetermined conditions.

[0049] As described above, the angle between the optical axis of the light emitted from the light-emitting device to the subject in the surrounding environment and the plane at the eye level of the subject 100 is in the range of about 30 degrees, or about 40 degrees, or about 45 degrees, up to about 90 degrees, or up to about 80 degrees, or up to about 60 degrees. In some embodiments of the present disclosure, the light-emitting device is moved by an adjustment mechanism so that the light from the light-emitting device satisfies the above conditions. In some embodiments of the present disclosure, the subject controls the adjustment mechanism to change the height of the light-emitting device and / or change the elevation angle of the light-emitting device so that the light from the light-emitting device satisfies the above conditions.

[0050] Furthermore, the subject in the surrounding environment may be exposed to ambient light having a vertical illuminance of approximately 3600 lux to approximately 4800 lux and / or a horizontal illuminance of approximately 2200 lux to 2800 lux, and the vertical illuminance and / or the vertical illuminance of green light or green spectral components, and the horizontal illuminance and / or the horizontal illuminance of green light or green spectral components are measured at the height level of the subject's ear, eye, or top of head. In some embodiments of this disclosure, the luminance of the light-emitting device is controlled by a controller so that the vertical illuminance of the light on the subject satisfies the above conditions. In some embodiments of this disclosure, the light-emitting device is moved by an adjustment mechanism so that the vertical illuminance of the light on the subject satisfies the above conditions.

[0051] In operation 65, after the light emitted from the light-emitting device into the surrounding environment is adjusted to meet predetermined conditions (which may be multiple), the subject can be exposed to the light, and the lighting system can apply phototherapy to the subject. [Examples]

[0052] Testing and Verification 1.1. Research Plan This study followed a single-blind longitudinal-group experimental design using a between-group trial, with group assignments determined by acceptance order. Diagnosis of dementia requires a history of cognitive decline and impairment in daily living activities, supported by primary caregivers and nursing staff in care facilities. Furthermore, a mental state assessment by a clinician is necessary to determine impairments in visuospatial cognition (including memory, language, attention, and spatial orientation), executive function, and mood. Participants in the experimental and comparison groups were exposed to ambient light (2500 lux) and general lighting, respectively.

[0053] 1.2. Participants The required sample size was calculated using G*Power 3.1 computer software and estimated to be 20 participants. The data were analyzed using analysis of variance (ANOVA) under conditions of statistical significance α=0.05 and β=0.2, and effect size f=0.39. Participants were selected based on the following inclusion criteria: 1) diagnosed with dementia according to the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5); 2) aged between 60 and 95 years; 3) consent to participate in the study for each participant or their guardian; and 4) willingness to participate in the group. Participants were excluded if: 1) they had adverse reactions to light, such as systemic lupus erythematosus, epilepsy, blindness, retinal detachment, or macular degeneration; 2) baseline sleep disturbance data collected using an accelerometer showed a sleep efficiency of more than 80%, fewer than 4 nighttime awakenings, fewer than 3 sleep disturbances per week, or sleep interruptions lasting less than 1 month; or 3) they had a measurement score of less than 3 points on the Mini-Mental State Examination (MMSE) or were unable to verbally express their will.

[0054] Of the 60 eligible patients, 11 did not meet the inclusion criteria and 14 declined to participate. Therefore, the inventors included 35 patients and subsequently assigned them to an experimental group (n=17) and a control group (n=18). Of these, 13 patients declined to participate in the study for reasons such as not having family to accompany them to daily treatment (n=9), suffering from pneumonia or a leg injury (n=2), or being unable to integrate into the group (n=2). Ultimately, only 22 patients completed the entire trial (Figure 8). Patients were required to attend the experimental facility five days a week.

[0055] 1.3. Experimental group: Ambient light therapy model The experimental group was exposed to ambient light of 2500–2600 lux and 4000–4400 lux, respectively, from panel lighting (QBX801K99) in a special room, as described in this application. To provide exposure, ambient light was positioned on the ceiling within a 45-degree field of view using full-spectrum light (2500 lux or more) (Figure 9A). Participants were exposed to ambient light for at least 60 minutes per day, Monday through Friday, from 9:00 AM to 10:00 AM, for eight weeks. In total, as a group, participants were exposed to ambient light for 40 hours. Horizontal lighting started at 500 lux and was increased by 500 lux daily, reaching and maintaining 2500 lux. Participants sat in chairs approximately 1.2 m away from the ambient light source at eye level. Ambient light at 2500 lux was standardized using a CL-500A illuminometer, and the same parameters were applied throughout the trial period. The ambient light was switched off and the curtains were drawn to enhance artificial ambient exposure. Furthermore, special aluminum windows completely shielded participants from external light. Light measuring instruments were used to ensure consistency between experimental parameters and light exposure. To reduce the interference factors of sunlight, participants were provided with sunglasses to wear before going outdoors.

[0056] 1.4. Comparison Group: General Lighting Models Participants in the control group were exposed to general lighting with horizontal and vertical illumination ranging from 114 lux to 307 lux and 600 lux to 800 lux, respectively (Figure 9B). They were placed in rooms without windows, and in some rooms, partitioned by curtains, to maintain a constant illumination level throughout the experiment.

[0057] 1.5. Feasibility: Retention rate, attendance rate, and adverse events Profile follow-up was completed for all participants in both the experimental and control groups. 35 participants completed baseline assessments, and 29 and 22 participants completed assessments at weeks 5 and 9, respectively. The retention rate was 64.7% in the experimental group and 61.1% in the control group. Attendance rates were 93% in the experimental group and 75% in the control group. No adverse effects (e.g., falls, injuries, eye injuries, headaches, and dizziness) were observed during the 8 weeks of phototherapy.

[0058] 2.1. Equipment and Outcome Measurement In this application, demographic data, as well as sleep efficiency, sleep duration, number of nighttime awakenings, wake duration, and circadian rhythms, were collected and determined using an accelerometer. Data were collected at baseline and at weeks 5 and 9. Data collectors were blinded to participants. Furthermore, behavioral and psychological symptoms of dementia (BPSD) were determined using the Neuropsychiatric Inventory (NPI), and cognitive function outcomes were obtained using the MMSE. NPI data were obtained through interviews with corresponding caregivers and care facility staff, while MMSE data were obtained directly by the researchers.

[0059] 2.2.1. Demographic data of participants Demographic data included sex, age, education level, marital status, sleep patterns, type of dementia, severity of dementia, source of dementia, total daily physical activity, and drug use (benzodiazepines, antidepressants, antipsychotics, and anti-dementia drugs).

[0060] 2.2.2. Defined daily dose (DDD) According to the World Health Organization (WHO), the prescribed daily dose (DDD) is the estimated mean maintenance dose of a drug per day in adults. DDD represents only the unit of measurement, and the amount of drug used (in DDD) is calculated as the total drug dose using DDD. To monitor the impact of drug changes on our findings, evaluations were performed at baseline and at weeks 5 and 9.

[0061] 2.2.3. Effectiveness and Reliability of Accelerometers In sleep measurement using accelerometers, hand movements, rather than body movements, are detected along three axes. Specifically, accelerometer activity is recorded as acceleration along the x, y, and z axes in three-dimensional space. Compared to polysomnography, accelerometers have high sensitivity and low specificity, and can also detect sleep disorders, circadian rhythms, and total physical activity for the day.

[0062] Sleep disorder data monitored with an accelerometer was recorded using the accelerometer. Compared to sleep logs of elderly individuals with dementia, the inter-measurement error was less than 30 minutes, and the accuracy level of the accelerometer (XA-5, Taipei, Taiwan) was 80%. The accelerometer (XA-5) was worn on the wrist, and actigraphic data was continuously recorded for more than 3 days at baseline using the KY Laboratory software package (http: / / xds.ym.edu.tw / sl). The device includes a piezoelectric linear accelerometer and associated circuitry for recording exercise intensity and physical activity-related movements, thereby yielding three variables: total physical activity (average of all active movements per hour), maximal activity (highest and / or maximum movement per hour), and average activity (average movement per hour).

[0063] 2.2.4. Sleep Patterns Sleep and wake times were observed for one week, based on reports from caregivers and nursing staff at care facilities. Furthermore, patterns were classified as advanced sleep-wake phase disorder, delayed sleep-wake phase disorder (DSWPD), irregular sleep-wake rhythm disorder, or sleep-wake rhythm disorder. Sleep pattern data monitored with an accelerometer was recorded using the accelerometer. The inter-measurement error was less than 30 minutes compared to sleep logs of elderly individuals with dementia. An accelerometer (XA-5, Taipei, Taiwan) was worn around the wrist, and actigraphic data was continuously recorded for at least three days at baseline using the KY Laboratory software package.

[0064] 2.2.5. Mini-Mental State Examination The MMSE was developed by Folstein et al. for quantitative dementia-related cognitive screening on a scale of 0 (worst) to 30 (best). The MMSE possesses good test-retest reliability (0.80–0.95), sensitivity, and specificity for detecting mild dementia stages. In this application, the MMSE demonstrated appropriate overall internal consistency (α=0.85). The MMSE is divided into categories: orientation [e.g., orientation questions, 5 questions each on time and place (10 points)], encoding [e.g., encoding 3 words and recalling for 1 minute (3 points)], attention and calculation [e.g., evaluated by either consecutive subtraction of 7 from 100 or consecutive subtraction of 3 from 20 (5 points)], recall [e.g., a 3-item recall test on memory (3 points)], and language and visuospatial construction [e.g., evaluated by three-stage commands, repetition, naming, reading comprehension, and writing (8 points) and copying two intersecting pentagons (1 point)] (Graf et al., 2001). The Cronbach's alpha coefficients for elderly individuals with dementia were 0.81 and 0.88 in the pre- and post-tests, respectively. The severity of dementia was assessed using the MMSE. A score of 21 or higher indicates the presence of mild dementia, 11-20 indicates moderate dementia, and 0-10 indicates severe dementia.

[0065] 2.2.6. Assessment of Neuropsychiatric Symptoms The Non-Psychopathological Inventory (NPI), developed by Cummings et al. (1994) (see also Connor et al. (2008) and Lai (2014)), assesses psychopathological and neuropsychiatric behaviors associated with dementia. The NPI comprises four domains: affective symptoms (e.g., nervousness, anxiety, apathy, euphoria, and irritability), psychiatric symptoms (e.g., delusions and hallucinations), behavioral problems (e.g., agitation, disinhibition, abnormal motor behavior, appetite, and feeding disorders), and sleep disorders (e.g., nocturnal behavior disorders) (Connor et al., 2008). The NPI exhibits good content validity, concurrent validity, and interrater reliability. Caregivers were asked to rate the frequency of each disorder symptom on a scale from 1 (occasionally or less than once a week) to 4 (very frequently, more than twice a day, or consecutively). Symptom severity was assessed on a scale of 1, 2, or 3 for mild, moderate, or severe. Total scores ranged from 0 to 144 points, with higher scores reflecting a more severe level of BPSD. The NPI subdomain was significantly correlated with the behavioral disorder domain and the Hamilton Rating Scale for Depression. Inter-rater reliability ranged from 93.6% to 100%, depending on the subdomain, and test-retest reliability was also high, with r(20) = 0.79 (Cummings et al., (1994), Connor et al., (2008), Lai, (2014), Cloak and Al Khalili, (2021)). In this study, the NPI demonstrated appropriate overall internal consistency (α = 0.66). Cronbach's alpha coefficients for older adults with dementia were 0.56 and 0.75 in the pre- and post-hoc studies, respectively.

[0066] 2.2.8.Statistical analysis Statistical analysis was performed using SPSS 24.0 statistical software. Demographic characteristics considered included sex, education level, marital status, sleep patterns, dementia type, and dementia origin. Descriptive statistics were calculated at baseline and at weeks 5 and 9 to examine whether participant loss affected demographic characteristics. Descriptive statistics are presented as case count (n), percentage (%), mean, and standard error, depending on the group. Primary pre- and post-trial analyses were performed based on intention to treat (ITT) samples. For inferential statistics, nonparametric statistics (chi-square test and Mann-Whitney U test) were used for between- and within-group comparisons of pre- and post-intervention profiles. Specifically, the Mann-Whitney U test was used to assess within-group differences in age and medication (benzodiazepines, antidepressants, antipsychotics, and anti-dementia drugs) at baseline. Independent sample t-tests were used to assess sleep efficiency, sleep duration, wake time, number of nighttime awakenings, circadian rhythm, and total daytime physical activity. DDD was used as the unit of drug use. A generalized estimating equation (GEE) was used for between-group comparisons to assess intervention effects, taking into account possible outcomes of repeated measures. Improvements in outcomes over time in both groups were analyzed using GEE with interchangeable working correlation matrices. Statistical significance was calculated using robust standard errors. The applicant tested the main effects of groups (experimental group and control group) and time points (baseline, week 5, and week 9), as well as their interactions (group_time point). Significant interaction effects showed significant between-group differences in changes over time. Benzodiazepines and total daytime physical activity were included as covariates in the GEE.

[0067] 3. Sleep disorders in elderly people with dementia 3.1. Demographic and Clinical Characteristics Figure 8 shows the flowchart of this study. In this study, 35, 31, and 22 participants completed evaluations at baseline, week 5, and week 9, respectively. The retention rates in the experimental and control groups were 64.7% and 61.1%, respectively. There were no significant differences between groups in demographic characteristics (education level, marital status, sleep patterns, dementia severity, dementia type, and cause) at baseline, week 5, and week 9. This indicates a homogeneous distribution of participants. However, there was a significant difference between groups in sex, with males accounting for 5.9% and 33% of patients in the experimental and control groups, respectively (P<0.05). Most participants were female. Furthermore, the mean ages of the experimental and control groups were 83.9 years (SD=7.1 years) and 80.2 years (SD=7.2 years), respectively, and there were no significant differences between the groups in terms of age, education level, marital status, sleep patterns, dementia severity, dementia type, cause, medication, or total physical activity on the day. This indicates a homogeneous distribution of participants.

[0068] 3.2. Effects of bright ambient light on sleep disorders As shown in Table 1, sleep disorders among participants were analyzed using independent sample t-tests. There were no significant differences between groups in sleep efficiency, sleep duration, wake time, and total physical activity on any given day. However, there was a significant difference between groups in the number of nighttime awakenings (5.6 and 7.5 in the experimental and comparison groups, respectively; P<0.05). This indicates that the distribution of sleep disorders among participants was homogeneous.

[0069] [Table 1]

[0070] Benzodiazepines and total daily activity were the main covariates of the group-specific interaction effect on sleep efficiency. Figure 10A shows the group, time, and interaction effect. The experimental group showed significantly improved sleep efficiency from baseline to weeks 5 and 9 (Wald's test = 18.85, P<0.001, and Wald's test = 9.91, P=0.002), which was higher than the improvement in the comparison group. Specifically, the experimental group showed mean sleep efficiency increases of 41.9% and 37.1% at weeks 5 and 9, respectively (calculation method: post-hoc study - pre-hoc study) / pre-hoc study). However, there was no significant difference in sleep efficiency between weeks 5 and 9 (Wald's test = 0.9, P=0.33). The experimental group showed a significant improvement in sleep duration compared to the control group (Wald's test = 11.5, P = 0.001, and Wald's test = 6.9, P = 0.008) (Figure 10B). Specifically, the experimental group showed an average increase in sleep duration of 141 minutes (43.7%) and 135 minutes (41.7%) in weeks 5 and 9, respectively. However, there was no significant difference in sleep duration between weeks 5 and 9 (Wald's test = 0.01, P = 0.09). The experimental group also showed a significant improvement in wakefulness time compared to the control group (Wald's test = 13.0, P = 0.001, and Wald's test = 9.1, P = 0.002) (Figure 10C). Specifically, the experimental group showed an average decrease in wakefulness time of 116 minutes (49.1%) and 108 minutes (45.6%) in weeks 5 and 9, respectively. Furthermore, the number of nighttime awakenings decreased by 23.2% (Wald's test = 1.1, P = 0.28) and 13.5% (Wald's test = 0.09, P = 0.75) in the experimental group and the comparison group, respectively, with no difference between week 5 and week 9 (Figure 10D). The improvement in the experimental group was most significant in terms of wake time, followed by sleep duration, sleep efficiency, and the number of nighttime awakenings. As shown in Table 1, the comparison group showed greater sleep disturbances in sleep efficiency, sleep duration, wake time, and the number of nighttime awakenings at week 5 and week 9 compared to baseline.

[0071] 3.3. Effects of bright ambient light on circadian rhythms The experimental group showed a significantly higher improvement in sleep onset than the comparison group (Wald's test = 2.42, P > 0.05, and Wald's test = 5.03, P < 0.01). Specifically, sleep onset in the experimental group advanced by 60 minutes and 84 minutes at weeks 5 and 9, respectively. In contrast, the comparison group showed a regression in sleep onset compared to baseline at weeks 5 (47 minutes) and 9 (21 minutes). The experimental group also showed a significantly higher improvement in sleep end-of-sleep time than the comparison group (Wald's test = 4.72, P < 0.05, and Wald's test = 7.41, P < 0.01). Specifically, sleep end-of-sleep time in the experimental group delayed by 57 minutes and 79 minutes at weeks 5 and 9, respectively. In contrast, the comparison group showed an earlier sleep end-of-sleep time compared to baseline at weeks 5 (19 minutes) and 9 (32 minutes), as shown in Figure 11 and Table 2.

[0072] [Table 2]

[0073] This embodiment demonstrates that ambient light is more effective than general lighting in improving sleep disorders and circadian rhythms in elderly individuals with dementia. Specifically, ambient light therapy significantly increases sleep efficiency and sleep duration, while reducing wakefulness. At weeks 5 and 9, sleep onset could be advanced by 60 and 84 minutes compared to baseline, while sleep end could be delayed by 57 and 79 minutes compared to baseline.

[0074] 4. Symptoms and cognitive function of dementia 4.1. Demographics and clinical characteristics of participants Thirty-five participants completed the baseline assessment, and 29 and 22 participants completed the assessments at weeks 5 and 9, respectively. No statistically significant differences were observed between the experimental and control groups in demographic characteristics (education level, marital status, sleep patterns, dementia type, dementia severity, and cause at baseline or at weeks 5 and 9). This indicates a homogeneous distribution of participants. Conversely, a statistically significant difference was observed in sex, with male participants accounting for 5.9% and 33% of the experimental and control groups, respectively (P<0.05), while the majority of participants were female. Baseline age, NPI and MMSE scores, and medication were assessed using the Mann-Whitney U test. The results showed no significant differences in age, medication, and MMSE scores. However, a statistically significant difference was observed in NPI scores between the two groups (mean NPI across 36 fractions in the experimental group and 21 fractions in the control group; P<0.006). The experimental group had more severe BPSD at baseline than the control group.

[0075] 4.2. Primary Outcome 4.2.1. Effects of light therapy on behavioral and psychological symptoms of dementia NPI was used as the neuropsychobehavioral outcome indicator for the effect of light intervention. The experimental group showed significant improvement in NPI from baseline to weeks 5 and 9 compared to the control group (Wald's test = 12.59, P < 0.001; Wald's test = 10.39, P = 0.001). The main effect on BPSD was demonstrated by a significant change in the gradient reflecting improvement in BPSD (Figure 12). The experimental group showed significant improvement in NPI, with mean decreases of 65% (calculation method: pre-test - post-test / pre-test) and 78% at weeks 5 and 9, respectively. However, the difference in NPI between weeks 5 and 9 was not statistically significant (Wald's test = 0.2, P = 0.65).

[0076] 4.2.2. Effects of light therapy on cognitive function MMSE was used as the cognitive function outcome indicator for the effect of group light therapy intervention. The experimental group showed significant improvement in MMSE scores from baseline to weeks 5 and 9 compared to the control group (Wald's test = 7.2, P<0.007; Wald's test = 3.9, P=0.04). The main effect on cognitive function was observed. Significant changes in the gradient reflect improved cognitive function (Figure 13). The experimental group showed significant improvement in MMSE scores, with mean increases of 19% (calculation method: post-hoc study - pre-hoc study / pre-hoc study) and 28% at weeks 5 and 9, respectively. However, there was no significant difference in MMSE scores at weeks 5 and 9 (Wald's test = 1.5; P=0.20).

[0077] 4.3 Secondary Outcomes The NPI is categorized into assessments of emotional state, psychiatric symptoms, behavioral disorders, and sleep disorders (Figures 14A-14D). Regarding specific neuropsychobehavioral domains of emotional state, psychiatric symptoms, and sleep disorders, sustained and promising improvement was observed in sleep disorders (Figure 14D). The experimental group showed significant improvement in sleep disorders from baseline to weeks 5 and 9 (Wald's test = 3.9, P < 0.002; Wald's test = 10.0, P = 0.04), which was greater than that in the control group.

[0078] The experimental group showed the greatest mean improvement from baseline, with the highest values ​​observed in sleep disorders, followed by psychiatric symptoms, emotional state, and behavioral disorders. However, in the comparison group, the greatest mean improvement was in sleep disorders, followed by emotional state, behavioral disorders, and psychiatric symptoms. In both the experimental and comparison groups, the domain with the greatest change was psychiatric symptoms (Figure 14B).

[0079] The MMSE is divided into orientation, encoding, attention and calculation, recall, and verbal visuospatial construction (Figures 15A-15E). Significant changes in the gradient for specific cognitive function domains reflected better performance in orientation, encoding, attention and calculation, recall, and verbal visuospatial construction. Of these domains, orientation showed the greatest improvement (Figure 15A). The experimental group showed a greater and more significant improvement in orientation than the control group from baseline to weeks 5 and 9 (Wald's test = 10.1, P = 0.001; Wald's test = 8.73, P = 0.003).

[0080] The experimental group showed greater improvements compared to baseline in attention and calculation, followed by orientation, recall, verbal visuospatial construction, and memory. However, the greatest improvements in the comparison group were observed in attention and calculation, followed by recall, memory, verbal visuospatial construction, and orientation. In both the experimental and comparison groups, orientation was the domain with the greatest change (Figure 15A).

[0081] This case study demonstrated that light therapy is more effective than general lighting in improving BPSD and cognitive function in elderly individuals with dementia. Light therapy reduced BPSD and improved cognitive function. Outcomes at weeks 5 and 9 were not significantly different, but a significant effect was observed with 4 weeks of light therapy. Therefore, 4 weeks of therapy is recommended, partly because the period of high adherence and acceptance required from participants is relatively short. Regarding NPI subdomains, significant improvement in sleep disorders was observed. The NPI subdomain with the greatest mean improvement was sleep disorders in both the experimental and control groups, while the domain with the greatest change in both groups was psychiatric symptoms. Regarding specific cognitive domains, the domains with the greatest mean improvement were attention and calculation in both the experimental and control groups, while the domain with the greatest change in both groups was orientation.

[0082] As used herein, the singular terms “a,” “an,” and “the” may include multiple references unless the context otherwise explicitly indicates.

[0083] As used herein, the terms “approximately,” “substantially,” “effectively,” and “about” are used to describe and explain small variations. When used in conjunction with events or situations, these terms may refer to the event or situation occurring exactly as it would, as well as to the event or situation occurring by close approximation. For example, when used in conjunction with a number, these terms may refer to a range of variation of that number of ±10%, such as ±5%, ±4%, ±3%, ±2%, ±1%, ±0.5%, ±0.1%, or ±0.05%. For example, two numbers may be considered “substantially” the same or equal if the difference between the values ​​is within ±10% of the mean of the values, such as ±5%, ±4%, ±3%, ±2%, ±1%, ±0.5%, ±0.1%, or ±0.05%. For example, "substantially" parallel may refer to a range of angular variation with respect to 0 degrees that is ±10 degrees or less, e.g., ±5 degrees or less, ±4 degrees or less, ±3 degrees or less, ±2 degrees or less, ±1 degree or less, ±0.5 degrees or less, ±0.1 degrees or less, or ±0.05 degrees or less. For example, "substantially" perpendicular may refer to a range of angular variation with respect to 90 degrees that is ±10 degrees or less, e.g., ±5 degrees or less, ±4 degrees or less, ±3 degrees or less, ±2 degrees or less, ±1 degree or less, ±0.5 degrees or less, ±0.1 degrees or less, or ±0.05 degrees or less.

[0084] Furthermore, quantities, ratios, and other numerical values ​​may be presented in range form in this specification. Such range forms are used for convenience and conciseness and include numerical values ​​explicitly designated as limits to the range, but should be understood flexibly to also include all individual numerical values ​​or subranges contained within that range, as if each numerical value and subrange were explicitly designated.

[0085] This disclosure is described and illustrated with reference to specific embodiments, but these descriptions and illustrations are not limiting to the disclosure. Those skilled in the art will understand that various modifications can be made and replaced with equivalents without departing from the true spirit and scope of the disclosure as defined by the appended claims. The drawings may not necessarily be drawn to scale. Due to manufacturing processes and tolerances, there may be differences between the technical representations in this disclosure and actual apparatus. Other embodiments of this disclosure that are not specifically illustrated may exist. The specification and drawings should be considered illustrative, not limiting. Modifications can be made to adapt specific circumstances, materials, compositions, methods, or processes to the purpose, spirit, and scope of this disclosure. All such modifications are intended to fall within the scope of the claims appended herein. The methods disclosed herein are described with reference to specific operations performed in a specific order, but it will be understood that these operations can be combined, subdivided, or rearranged to form equivalent methods without departing from the teachings of this disclosure. Therefore, unless specifically indicated herein, the order and grouping of operations are not limitations of this disclosure.

Claims

1. A lighting system used in the surrounding environment, A light-emitting device configured to provide light to a subject in the surrounding environment, A controller electrically coupled to the light-emitting device and configured to control the light-emitting device, Equipped with, A lighting system wherein the light provided by the light-emitting device comprises at least 30% green light having a wavelength of 450 nm to 580 nm, a line extending from the light-emitting device to the subject and a plane at the subject's eye level in the surrounding environment form a 45-degree angle, and the light has a horizontal illuminance of 2200 lux to 2800 lux and a vertical illuminance of 3600 lux to 4800 lux.

2. The lighting system according to claim 1, wherein the horizontal illuminance of the light is measured on the plane at the eye level of the subject.

3. The lighting system according to claim 1, wherein the color temperature of the light provided by the light-emitting device is at least 4000K.

4. The lighting system according to claim 1, wherein the proportion of blue light spectral components having wavelengths of 415 nm to 460 nm in the light is reduced, and the proportion of blue light spectral components having wavelengths of 465 nm to 490 nm in the light is maintained.

5. The lighting system according to claim 1, wherein the light provided by the light-emitting device has a color fidelity (Rf) greater than 90 and a color gamut (Rg) greater than 95.

6. The lighting system according to claim 1, wherein the light provided by the light-emitting device has a color rendering index (CRI) in the range of 85 to 98.

7. The lighting system according to Claim 1, wherein the light-emitting device includes a group of red light LEDs, a group of green light LEDs, and a group of blue light LEDs, the number of LED units in the red light LED group is N, the number of LED units in the green light LED group is M, and the number of LED units in the blue light LED group is L, and 0.4 ≤ M / (N + M + L).

8. The lighting system according to claim 1, wherein the light spectrum of the light provided by the light-emitting device is similar to the solar spectrum.

9. The lighting system according to claim 1, further comprising an adjustment mechanism connected to the light-emitting device, wherein the adjustment mechanism includes a lifting platform configured to change the height of the light-emitting device and a head configured to change the elevation angle of the light-emitting device.

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