JP4142944B2 - LIGHTING DEVICE, LIGHTING CONTROL DEVICE, AND LIGHTING CONTROL METHOD - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lighting system for an observer to easily arrange the rhythm of respiration according to a variation in brightness of light when the eyes are closed to be easily fallen into a sleep, light control device and a light control method. <P>SOLUTION: The lighting period of a light source 10 is divided into a respiration control time and an adaptation period, and a control part 20 controls the light source 10 so that the brightness ratio C1(= LMAX<SB>1</SB>/LMIN<SB>1</SB>) of the maximum brightness LMAX<SB>1</SB>to the minimum brightness LMIN<SB>1</SB>in one frequency of a variation in brightness becomes substantially a constant value in the respiration control period, and so that, in the subsequent adaptation period, the brightness ratio (= LMAX<SB>2</SB>/LMIN<SB>2</SB>) of the maximum brightness LMAX<SB>2</SB>to the minimum brightness LMIN<SB>2</SB>in one frequency of the variation in brightness becomes substantially a constant value smaller than the brightness ratio C1 and that the maximum brightness LMAX<SB>2</SB>can vary along a dark adaptation curve. <P>COPYRIGHT: (C)2003,JPO

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an illumination device, an illumination control device, and an illumination control method that periodically change the luminance of illumination light.
[0002]
[Prior art]
With the aim of realizing a comfortable lighting environment, the inventors of the present application have studied a lighting device and a lighting control method that change the luminance of the lighting light at a frequency close to a breathing rhythm. In the study, if the amount of change in the brightness of the illumination light per cycle, that is, the ratio of the maximum brightness to the minimum brightness per cycle, is different, humans will receive from the illumination light when directly observing the change in the illumination light I found a different impression.
[0003]
Therefore, in order to achieve the optimal change in illumination light according to the human action situation (for example, adjusting the rhythm of breathing or relaxing the observer), the brightness of the illumination light according to the human action situation We examined how to change the luminance ratio of the maximum luminance to the minimum luminance per cycle. As a result, when the observer directly observes the illumination light, it is easy for the user (observer) to adjust the breathing rhythm in accordance with the change in the brightness of the illumination light, and the user can easily relax. Have developed a lighting device and a lighting control method (Patent Document 1).
[0004]
[Patent Document 1]
Japanese Patent Laid-Open No. 11-96809
[0005]
[Problems to be solved by the invention]
One of the situations where humans need to be relaxed is a sleep state. If you can't relax when you fall asleep, you won't be able to get enough sleep comfortably, and in some cases you will suffer from insomnia. Therefore, if the lighting device can be used at the time of falling asleep, the user can easily fall asleep and a comfortable sleep can be obtained.
[0006]
It is normal to close the eyes when falling asleep, and it is desirable to remove as much of the dazzling light as possible. Therefore, at the time of falling asleep, it is necessary to reduce the amount of illumination light as much as possible to make it dark.
[0007]
In order to make it easy for the user to adjust the rhythm of breathing to the change in the amount of illumination light when using the lighting device, in addition to being able to perceive the illumination light through the eyelid even in the closed eye state, the user does not feel dazzling Thus, the amount of illumination light must be sufficiently small, that is, sufficiently dark. Furthermore, at that time, it is necessary to consider the dark adaptation function of human vision. The dark adaptation function means that the sensitivity of human eyes increases so that an object can be seen well in a dark place where the amount of illumination light is small. When the user falls asleep, the user is in an extremely dark environment with his eyes closed, so it is clear that dark adaptation progresses considerably over time. As a result, the sensitivity of vision increases with the passage of time, and the illumination light that was initially appropriate gradually becomes dazzling, which may hinder sleep falling asleep.
[0008]
The conventional lighting device does not consider use during sleep, particularly the dark adaptation function of human vision. Therefore, when using during sleep, control in consideration of the dark adaptation function of vision is required. .
[0009]
An object of the present invention is to provide an illumination device, an illumination control device, and an illumination control method that allow a user to adjust the rhythm of breathing in accordance with a change in luminance of illumination light and that are also suitable for use during sleep. .
[0010]
[Means for Solving the Problems]
An illuminating device according to the present invention is an illuminating device including a light source and a control unit that controls the light source so that luminance of a light emitting surface of the light source periodically changes. The lighting period is divided into at least a breathing adjustment period and an adaptation corresponding period in order, and in the breathing adjustment period, the minimum luminance L in one cycle of the luminance change of the light emitting surface of the light source. _MIN1 Maximum luminance L for _MAX1 Luminance ratio C1 (= L _MAX1 / L _MIN1 ) Is substantially equal to a certain value, and the light source is controlled, and in the adaptation corresponding period, the minimum luminance L in one cycle of the luminance change of the light emitting surface of the light source. _MIN2 Maximum luminance L for _MAX2 Luminance ratio C2 (= L _MAX2 / L _MIN2 ) Substantially equal to a certain value smaller than the luminance ratio C1, and the maximum luminance L _MAX2 Controls the light source so that it changes along the dark adaptation curve R.
[0011]
Further, the control unit sequentially divides the lighting period of the light source into at least the breathing adjustment period, the transition period, and the adaptation corresponding period, and in the transition period, the minimum luminance in one cycle of the luminance change of the light emitting surface of the light source L _MIN3 Maximum luminance L for _MAX3 Luminance ratio C3 (= L _MAX3 / L _MIN3 ) Is preferably controlled so that the luminance ratio C1 gradually decreases from the luminance ratio C1 to the luminance ratio C2.
[0012]
The range of the luminance ratio C1 is preferably 10 <C1 ≦ 100, and the range of the luminance ratio C2 is preferably 6 <C2 ≦ 100.
[0013]
The dark adaptation curve R has a luminance value L2 that decreases monotonously as time elapses from the luminance value L1 at the start of the adaptation corresponding period, and is smaller than the luminance value L1 and larger than L1 / 10. The time from the start of the adaptation corresponding period is t (minutes), and the time required for the dark adaptation curve R to reach from the luminance value L1 to the luminance value L2 is AT (minutes). As 0 ≦ t <5,
L1 x (L2 / L1) ^{t / AT} ≦ L ≦ L1
Satisfying 5 ≦ t ≦ AT,
L1 x (L2 / L1) ^{t / AT} ≦ L
≦ L1- (L1-L2) × (t-5) / (AT-5)
It is preferable that the curve satisfies the above.
[0014]
The luminance value L2 is preferably L1 / 2 or less and L1 / 10 or more.
[0015]
Further, it is preferable that a sensor for detecting the wakefulness state of the observer is further provided, and that the light emission of the light source is automatically stopped when it is determined that the observer has entered a sleep state.
[0016]
Moreover, it is preferable that the said sensor acquires an observer's brain wave data and detects an observer's arousal state.
[0017]
Or it is preferable that the said sensor acquires an observer's electrocardiogram data and detects an observer's arousal state.
[0018]
The illumination control device of the present invention is an illumination control device that controls the light source so that the luminance of the light emitting surface of the light source changes periodically, and the lighting period of the light source is sequentially set to at least a breathing adjustment period and an adaptation corresponding period. In the respiration adjustment period, the minimum luminance L in one cycle of the luminance change of the light emitting surface of the light source is divided. _MIN1 Maximum luminance L for _MAX1 Luminance ratio C1 (= L _MAX1 / L _MIN1 ) Is substantially equal to a certain value, and the light source is controlled, and in the adaptation corresponding period, the minimum luminance L in one cycle of the luminance change of the light emitting surface of the light source. _MIN2 Maximum luminance L for _MAX2 Luminance ratio C2 (= L _MAX2 / L _MIN2 ) Substantially equal to a certain value smaller than the luminance ratio C1, and the maximum luminance L _MAX2 Controls the light source so that it changes along the dark adaptation curve R.
[0019]
Further, it is preferable that a sensor for detecting the wakefulness state of the observer is further provided, and that the light emission of the light source is automatically stopped when it is determined that the observer has entered a sleep state.
[0020]
The lighting control method of the present invention includes: In lighting control equipment An illumination control method for controlling the light source so that the luminance of the light emitting surface of the light source changes periodically, The controller of the lighting control device The lighting period of the light source is divided into at least a breathing adjustment period and an adaptation corresponding period in order, and in the breathing adjustment period, the minimum luminance L in one cycle of the luminance change of the light emitting surface of the light source. _MIN1 Maximum luminance L for _MAX1 Luminance ratio C1 (= L _MAX1 / L _MIN1 ) Is substantially equal to a certain value, and the light source is controlled, and in the adaptation corresponding period, the minimum luminance L in one cycle of the luminance change of the light emitting surface of the light source. _MIN2 Maximum luminance L for _MAX2 Luminance ratio C2 (= L _MAX2 / L _MIN2 ) Substantially equal to a certain value smaller than the luminance ratio C1, and the maximum luminance L _MAX2 Controls the light source so that it changes along the dark adaptation curve R.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, components having substantially the same function are denoted by the same reference numerals for the sake of simplicity. In addition, the present invention should not be construed as being limited to the following embodiments.
[0022]
1. Configuration of lighting device
A configuration of a lighting device according to an embodiment of the present invention will be described. FIG. 1 is a block diagram showing a configuration of a lighting apparatus 1 according to the present embodiment. The lighting device 1 includes a light source 10 and a control unit 20 that controls the light source 10 so as to periodically change the luminance of the light emitting surface of the light source 10.
[0023]
The control unit 20 includes a dimming signal generation unit 22 that generates a dimming signal, and a dimming lighting device 24 that controls the luminance of the light emitting surface of the light source 10 according to the dimming signal transmitted from the dimming signal generation unit 22. And. The dimming signal generation / transmission function of the dimming signal generation unit 22 is realized by, for example, a computer (CPU). The dimming signal generation unit 22 outputs a voltage signal (for example, a voltage signal of 0 to 5 V) that changes over time to the dimming lighting device 24 as a dimming signal. The dimming / lighting device 24 converts the change in the voltage signal output from the dimming signal generation unit 22 into a change in the current value supplied to the light source 10, and supplies the current to the light source 10. The light source 10 changes the luminance of the light emitting surface according to the magnitude of the current supplied from the dimming / lighting device 24. In other words, the luminance of the light emitting surface of the light source 10 changes corresponding to the change in the voltage of the dimming signal generated by the dimming signal generation unit 22.
[0024]
As the light source 10, any light source such as an incandescent bulb, a fluorescent lamp, a bulb-type fluorescent lamp, a high-intensity discharge lamp, an LED light source, an organic EL light source, or the like can be used as long as dimming can be realized.
[0025]
FIG. 2 schematically shows a state in which the observer (user) 30 observes the illumination light 20 from the light source 10 of the illumination device 1 while sleeping on the bed 40. The lighting device 1 includes a control unit 20 in a pedestal 1a, and the control unit 20 includes an outlet 1b for connection to a power source. The luminance of the illumination light 50 changes periodically in conjunction with the periodic change of the luminance of the light emitting surface of the light source 10.
[0026]
In the example shown in FIG. 2, the lighting device 1 is in the form of a floor stand, but the lighting device 1 is not limited to this form, and may be a short stand with a handle such as a desk stand, or on the ceiling. It may be a ceiling light to be attached, a lighting device for general lighting of a pendant type, a lighting device for partial illumination such as a downlight attached to the ceiling, and the like. Further, it goes without saying that the illumination device 1 may be a type of illumination device that has a shape that covers the eyes of the observer 30 such as a head-mounted display, glasses, and an eyepatch and that illuminates the eyes of the observer 30. Nor. Moreover, the control part 20 and the light source 10 may be comprised separately. When the control unit 20 and the light source 10 are configured separately, the control unit 20 can be used with any type of light source 10 and function as an illumination control device that controls the light source 10.
[0027]
Here, it is assumed that the observer 30 breathes in accordance with the change in the luminance of the illumination light 50. For example, it is assumed that the observer 30 inhales during a period from when the illumination light 50 is darkest to the brightest, and exhales during a period from when the illumination light 50 is brightest to the darkest. In addition, the observer 30 may exhale during a period from when the illumination light 50 is darkest to when it is brightest, and breathe during a period when the illumination light 50 is brightest until it becomes darkest.
[0028]
Thus, by breathing in accordance with the change in the luminance of the illumination light 50, the observer 30 can adjust the breathing rhythm. Thereby, the relax degree of the observer 30 is improved. Here, in this specification, “relaxation” includes not only stress relief but also a feeling of good sleep.
[0029]
In FIG. 2, the control unit 20 is housed inside the base 1 a of the lighting device 1, but may be housed inside a case or the like provided in the middle of the power supply line 1 b of the lighting device 1. good. Moreover, when the light source 10 is a light bulb-type fluorescent lamp provided with a lighting circuit, the lighting circuit portion may include the control unit 20.
[0030]
2. Principle of lighting control method
Next, the principle of the illumination control method according to this embodiment will be described. FIG. 3 schematically shows the principle of the illumination control method according to the present embodiment. In the illumination control method according to the present embodiment, the lighting period of the light source 10 is divided into at least a “respiration adjustment period” and an “adaptation corresponding period”. The adaptation response period is a period later in time than the breathing adjustment period.
[0031]
The observer 30 observes the illumination light 50 with the eyes closed. In the respiration adjustment period, the light source 10 is arranged so that the observer 30 with his eyes closed can easily adjust the respiration, that is, the illumination light 50 becomes “illumination light with which the observer with his eyes closed can easily respiration”. The brightness of the light emitting surface is controlled. Further, during the adaptation period, the light source 10 emits light so that the observer 30 whose eyes are closed is likely to fall asleep, that is, the illumination light 50 is “illumination light where the observer whose eyes are closed easily fall asleep”. The brightness of the surface is controlled. At this time, if illumination light having the same luminance is continuously irradiated for a long time, the above-mentioned dark adaptation function may result in “illumination light that makes it easy for an observer with eyes closed to fall asleep”. For this reason, in the adaptation response period, the luminance of the illumination light gradually decreases corresponding to the dark adaptation, and always provides “illumination light in which an observer who closes his eyes can easily fall asleep”.
[0032]
The adaptation corresponding period may be a period immediately following the breath adjustment period, but it is preferable that a transition period is provided between the breath adjustment period and the adaptation corresponding period. During this transition period, the illumination light 50 presented to the observer 30 gradually changes from “illumination light that allows an observer with closed eyes to easily breathe” to “illumination light that allows an observer with closed eyes to easily fall asleep”. The luminance of the light emitting surface of the light source 10 is controlled so as to change.
[0033]
Thus, according to the illumination control method according to the present embodiment, the observer 30 who has closed his eyes adjusts the breathing rhythm in accordance with the change in the luminance of the illumination light 50 in the breathing adjustment period, and then the adaptation corresponding period. It becomes possible to fall asleep at.
[0034]
Whether or not an observer with closed eyes can easily respire can be expressed only by a statistical method (for example, probability) because it is based on the psychological effect of the observer. Here, when the luminance of the illumination light is changed periodically, more than 50% of the plurality of observers say that the illumination light that says “it is easy to breathe with the eyes closed” It is defined as “illumination light that makes it easy for the observer to adjust breathing”. For example, when 10 observers observe the illumination light with their eyes closed, the illumination light that more than 5 observers answered, “Easy to adjust breathing with eyes closed” It is defined as “illumination light that makes it easy for an observer who has closed a breath to adjust”.
[0035]
Moreover, the illumination light is an obstacle to falling asleep when the illumination light feels dazzling or a change is felt intensely, resulting in an uncomfortable feeling. Therefore, when the brightness of the illumination light is changed periodically, more than 50% of the plurality of observers will receive the illumination light that says “not uncomfortable with eyes closed” It is defined as “lighting light that is easy to fall asleep”.
[0036]
3. Brightness ratio control
Next, in the illumination control method according to the present embodiment, the minimum luminance L in one cycle of the luminance change of the light emitting surface of the light source 10. _MIN Maximum luminance L for _MAX Luminance ratio C (= L _MAX / L _MIN ) Will be explained together with the characteristics of human vision.
[0037]
FIG. 4 is a diagram illustrating human visual characteristics. When human vision is stimulated by light, the stimulus is transmitted through nerves and transmitted to the brain. The magnitude of the stimulus transmitted to the brain is not proportional to the luminance of the light source, but is proportional to the logarithm of the luminance. FIG. 4 shows how a person perceives the illumination light when the person sees the illumination light whose luminance changes periodically along a sine waveform.
[0038]
FIG. 5 is a diagram illustrating how the two illumination lights X1 and X2 are perceived by a human. Although the illumination lights X1 and X2 are illumination lights that change periodically, the perceived amount is proportional to the logarithmic value as described above. Therefore, the magnitude (amplitude) of the change is in one cycle as shown in FIG. It is determined by the ratio of the maximum brightness and the minimum brightness. That is, if the ratio between the maximum luminance and the minimum luminance is the same, the illumination lights X1 and X2 are perceived as illumination lights having the same amplitude. Therefore, the magnitude of the change in the illumination light perceived by the observer in the illumination device that changes in luminance must be considered as a ratio, not a difference between the maximum luminance and the minimum luminance.
[0039]
Although the above description is about the case where the illumination light is observed in the open eye state, the same can be said when the illumination light is perceived through the eye lid in the closed eye state. In the closed eye state, light that permeates through the eye lid is perceived, but since the human eye lid is considered as a filter for incident light, the amount of light that is transmitted is proportional to the illumination on the eye lid (eye surface illumination). To do. If the light source has the same brightness at the same distance, the illuminance is proportional to the brightness, so the ocular illuminance ratio is the same as the brightness ratio of the light source. That is, the magnitude (amplitude) of the change in illumination light can be considered by the luminance ratio of the light source even in the closed eye state.
[0040]
When the amplitude of the brightness change of the perceived illumination light is large, that is, the brightness ratio is large, the illumination light imposes a heavy burden on vision and disturbs falling asleep. However, the periodic change of the illumination light is easy to understand, and it is easy to match the breathing rhythm with the change in the brightness of the illumination light. On the other hand, when the amplitude of the illumination light is small, that is, the luminance ratio is small, it becomes difficult to match the rhythm of respiration with the luminance change of the illumination light, but sleep is easy. Therefore, appropriately controlling the luminance ratio of the light source provides “illumination light that makes it easier for an observer with closed eyes to adjust their breathing” during the breathing adjustment period, and “when an observer with closed eyes falls asleep during the adaptation period. This is important for providing easy-to-use illumination light.
[0041]
In the lighting control method according to the present embodiment, the minimum luminance of the light emitting surface of the light source in one cycle of the periodic change in luminance is set to L during the breathing adjustment period. _MIN1 , Maximum brightness L _MAX1 As the minimum luminance L _MIN1 Maximum luminance L for _MAX1 Luminance ratio C1 (= L _MAX1 / L _MIN1 ) Is controlled so that the illumination light has a substantially constant value. Further, in the adaptation corresponding period, the minimum luminance of the light emitting surface of the light source in one cycle of the periodic change in luminance is expressed as L _MIN2 , Maximum brightness L _MAX2 As the minimum luminance L _MIN2 Maximum luminance L for _MAX2 Luminance ratio C2 (= L _MAX2 / L _MIN2 ) Is controlled so that the illumination light is substantially equal to a certain value smaller than the luminance ratio C1. Such control of the illumination light is achieved by controlling the light source 10. Here, in the present specification, the “substantially constant value” means including not only the case of “perfectly matching” but also the case of “different” by an error that can be caused by a normal design. To do. In addition, when a transition period is provided between the breathing adjustment period and the adaptation-corresponding period, the minimum luminance of the light emitting surface of the light source in one cycle of the luminance periodic change is set to L in the transition period. _MIN3 , Maximum brightness L _MAX3 As the minimum luminance L _MIN3 Maximum luminance L for _MAX3 Luminance ratio C3 (= L _MAX3 / L _MIN3 ) Gradually decreases from the luminance ratio C1 to the luminance ratio C2.
[0042]
However, when the minimum luminance is 0, the luminance ratio cannot be calculated. When the maximum brightness is very close to 0, no matter how much the brightness ratio is increased (the minimum brightness is reduced), it cannot be perceived, and the meaning of using the brightness ratio related to perception is lost. In general, since the luminance value is not discussed in the last three digits for perception, in this embodiment, even when the minimum luminance is 0.01 or less, the luminance is calculated as the minimum luminance ≈ 0.01. Let's calculate the ratio. For example, when the maximum luminance is 0.1 and the minimum luminance is 0, the minimum luminance is 0.01 and the luminance ratio is 10, and when the maximum luminance is 0.1 and the minimum luminance is 0.005, the minimum luminance is 0. 01 is a luminance ratio of 10.
[0043]
An example of such luminance ratio control is shown in FIG. The horizontal axis in FIG. 6 represents elapsed time, and the vertical axis represents the luminance of the light source. In FIG. 6, L _MAX1 , L _MIN1 , L _MAX2 , L _MIN2 Each is constant, but is not limited to this. As will be described later, in this embodiment, L _MAX2 , L _MIN2 Has a period that changes over time. L _MAX1 , L _MIN1 May be changed. However, the luminance ratios C1 and C2 are constant.
[0044]
4). Brightness ratio design
In order to realize the “illumination light that makes it easy for an observer with eyes closed to breathe” and “illumination light that makes it easy for an observer with eyes closed to relax” described with reference to FIG. 3, the luminance shown in FIG. It is important to design the ratios C1 and C2 corresponding to the closed eye state. In the present embodiment, the values of the luminance ratios C1 and C2 are designed based on experiments.
[0045]
FIG. 7 shows an example of an experimental environment used to design the values of the luminance ratios C1 and C2 shown in FIG. The control unit 20 controls the light source 10 so that the luminance of the light emitting surface 10b of the light source 10 changes periodically. By changing the parameter value set by the experimenter (operator) 60 in the control unit 20, it is possible to change the luminance of the light emitting surface 10 b of the light source 10. The observer 30 observes the illumination light 50 from the light source 10 with the eyelids closed. Here, between the light source 10 and the observer 30, a light shielding plate 10 a that restricts illumination light other than the light emitting surface 10 b out of the illumination light 50 emitted from the light source 10 is provided. Further, the light emitting surface 10b is made sufficiently large so that the diffused light is uniformly irradiated on the eyelid of the observer 30 in the closed eye state. The maximum eye surface of the illumination light reaching the eye surface of the observer 30 by changing the distance between the light emitting surface 10b and the observer 30 and the wattage of the light source 10 and using an ND filter that reduces the light amount of the light source 10 The range from illuminance to minimum ocular illuminance (several thousand lx to several lx) was made as large as possible. In particular, when falling asleep, it is clear that the lower the illuminance of the illumination light, the lower the illuminance of the illumination light. I was able to do it. That is, for the purpose of falling asleep, all experimental conditions of the illuminance on the surface of the observer 30 reproduced when using a general lighting device within a practical range were examined. The light source was only the light source 10 and the periphery at the time of observation was dark. All of the plurality of observers 30 had normal vision and color vision.
[0046]
In the following, detailed description will be given of how to design the values of the luminance ratios C1 and C2 shown in FIG.
[0047]
In the illumination control method according to the present embodiment, it is most important that an observer with his eyes closed can synchronize respiration with a change in luminance of illumination light. In order to synchronize respiration, it is necessary to be able to perceive at least the luminance cycle of the illumination light with the eyes closed. In addition, in order to perceive the cycle of the luminance of the illumination light, it is important to be able to perceive the maximum luminance and the minimum luminance of the illumination light. That is, it is necessary to find a lower limit value of the luminance ratio value of the maximum luminance with respect to the minimum luminance per cycle, so that an observer with his eyes closed can perceive the maximum luminance and the minimum luminance of the illumination light. In addition, since it is thought that it becomes easy to adjust respiration so that the change of illumination light is easy to understand, below, the ease of understanding of the change of illumination light and the ease of matching of respiration will be equated.
[0048]
In order to make it easy for the observer to fall asleep during the adaptation period, it is necessary to reduce the burden on the observer's eyes as much as possible. Therefore, the lower limit value of the luminance ratio C2 in the adaptation-corresponding period is the lower limit of the value of the luminance ratio of the maximum luminance with respect to the minimum luminance per cycle that allows an observer with closed eyes to perceive the maximum luminance and the minimum luminance of illumination light. It becomes the same as the value.
[0049]
Under the experimental environment shown in FIG. 7, the luminance ratio C (= L) at which the observer 30 with his eyes closed can perceive the maximum luminance and the minimum luminance of the illumination light. _MAX / L _MIN An experiment for obtaining the lower limit value of L _MAX Represents the maximum luminance per cycle on the light emitting surface of the light source 10, and L _MIN Represents the minimum luminance per cycle on the light emitting surface of the light source 10. These brightness | luminances respond | correspond to the observer's eye surface illumination (illuminance of the illumination light irradiated to an eyelid) in a fixed distance from an illuminating device. That is, the ratio between the minimum luminance and the maximum luminance is equal to the ratio between the minimum eye surface illuminance and the maximum eye surface illuminance. In the experiments shown in FIGS. 8 to 10 described below, four types of eye surface illuminances of 4 lx, 2 lx, 1 lx, and 0.5 lx were used. These ocular illuminances are achieved by controlling the luminance of the light source to be relatively the same.
[0050]
Ask each of the eight eyes-closed observers to respond when they feel that the brightness of the illumination light (more precisely, the illuminance on the surface of the eye) is maximum. The difference from the time at which the brightness of the is physically maximum was measured. It also asks for a response when it feels that the brightness of the illumination light (more precisely, the illuminance on the eye surface) is minimum, and the time when the observer responds and the time when the brightness of the illumination light is physically minimum The difference was measured.
[0051]
The same experiment was repeated five times for one observer. However, some observers may not be able to determine whether the luminance of the illumination light is maximum or minimum because the eyes are closed. As a result, the number of responses made by the observer varied. The average value of the measurement results of the response time for one observer was taken as the measurement result for that observer.
[0052]
The experimenter experimented by changing the luminance ratio of the light source in various ways. The button was pressed at the moment when the observer felt that the brightness of the illumination light was maximum or minimum with the eyes closed, and the time TS at that time was recorded. On the other hand, the luminance of the illumination light was measured, and the time TL when the measured luminance was maximum or minimum was recorded. The difference ΔT was calculated as ΔT = | TS−TL |.
[0053]
Here, the meaning of TS and ΔT will be described. An observer observes a change in luminance of illumination light in a closed eye state and adjusts respiration according to the observation result. Therefore, the time TS indicating the moment when the observer feels that the luminance of the illumination light is maximum is considered to be substantially the same as the time when the observer starts to exhale. Therefore, ΔT is considered to be the difference between the time when the observer starts to exhale and the time when the luminance of the illumination light becomes maximum. Therefore, as ΔT becomes smaller, the difference between the time when the observer starts to exhale and the time when the luminance of the illumination light becomes maximum becomes smaller, so the change in the luminance of the illumination light and the breathing of the observer are synchronized. It is thought that. Similarly, the time TS indicating the moment when the observer feels that the brightness of the illumination light is minimum is considered to be substantially the same as the time when the observer starts to breathe. Therefore, ΔT is considered to be the difference between the time when the observer starts to breathe and the time when the luminance of the illumination light is minimized. Therefore, as ΔT becomes smaller, the difference between the time when the observer starts to breathe and the time when the luminance of the illumination light becomes maximum becomes smaller, so the change in the luminance of the illumination light and the breathing of the observer are synchronized. It is thought that.
[0054]
As described above, depending on the observer, it may be impossible to determine whether the luminance of the illumination light is maximum or minimum because of the closed eye state. Therefore, it is considered that the number of responses is highly correlated with the fact that the observer who closed his eyes was able to perceive the maximum and minimum brightness of the illumination light. Therefore, a response rate RS was calculated by multiplying the number of times of response to the number of times of the presented illumination light by 100.
[0055]
The experimental results are shown in FIGS. L _MIN There was no difference in the results for the four types of 4lx, 2lx, 1lx, and 0.5lx. _MIN FIG. 8 (a), FIG. 9 (a), and FIG. 10 (a) show the results when 4 is 1x. _MIN FIG. 8B, FIG. 9B, and FIG. 10B show the results when is 0.5 lx.
[0056]
FIGS. 8A and 8B show experimental results regarding ΔT and the luminance ratio C2 of the illumination light in the adaptation corresponding period. 8A and 8B, the horizontal axis represents the luminance ratio C2 (= L _MAX2 / L _MIN2 ) On the logarithmic axis, and the vertical axis shows the difference ΔT (seconds). The square marks are the results when the luminance of the illumination light is maximum, and the circles are the results when the luminance of the illumination light is minimum. 8A and 8B, as the luminance ratio C2 increases, the difference ΔT monotonously decreases in both cases where the luminance is maximum and minimum. In addition, when the luminance is minimum, the difference ΔT becomes almost constant when the luminance ratio C2 is 4 or more. On the other hand, when the luminance is maximum, it can be seen that when the luminance ratio C2 is 6 or more, an inflection point of the difference ΔT is seen and gradually becomes constant. Therefore, when the luminance ratio C2 is 6 or more, the determination time when the observer who closes his / her eyes maximizes and minimizes the luminance of the illumination light becomes substantially constant.
[0057]
FIGS. 9A and 9B show experimental results regarding the response rate RS (%) and the luminance ratio C2 of the illumination light. In FIG. 9, the horizontal axis indicates the luminance ratio C2 by a logarithmic axis, and the vertical axis indicates the response rate RS (%). The square marks are the results when the luminance of the illumination light is maximum, and the circles are the results when the luminance of the illumination light is minimum. 9 (a) and 9 (b), it was found that when the luminance ratio C2 is 4 or more, the response rate RS is constant at about 90% in both the case where the luminance is maximum and the case where the luminance is minimum. .
[0058]
From the results of FIGS. 8 and 9, when the luminance ratio C2 is 6 or more, it is possible to determine when the luminance of the illumination light is maximum and minimum even when the observer is in an eye-closed state, and the response rate RS is 90. It became clear that an observer with closed eyes can synchronize respiration with changes in the intensity of illumination light. From the above, the minimum luminance L per cycle of the periodic change of the illumination light in the present embodiment. _MIN2 Maximum luminance L for _MAX2 Luminance ratio C2 (= L _MAX2 / L _MIN2 ) Must satisfy 6 ≦ C2. As described above, since C2 ≦ C1, the luminance ratio C1 in the breathing adjustment period is naturally 6 ≦ C1.
[0059]
Then, the result of having examined the luminance ratio C1 in the respiration adjustment period is shown. In designing the luminance ratio C1 during the introduction period, it is important that an observer who closes his eyes can easily breathe with the change in luminance of the illumination light. Since the ease of respiration can be equated with the ease of understanding the change in illumination light, each of the eight observers observed the illumination light 50 from the light source 10 with the eyelids closed. A subjective evaluation was made on whether or not the observer could easily understand the change in the brightness of the illumination light. The evaluation was made in four stages: “I understand well”, “I understand”, “I don't understand”, and “I don't know”. For each evaluation, points of +3, +2, +1, 0 were given in order, and the average value of 8 observers was calculated. An evaluation with an average score of 2 or more is equivalent to an observer evaluating “well understood” or “understood” with a psychological probability of 50% or more. The illumination condition when the score of the evaluation item is 2 or more is defined as “illumination condition that allows the change in brightness of the illumination light to be well understood when the eye is closed”, and “illumination light that makes it easy for an observer with eyes closed to breathe” .
[0060]
FIGS. 10A and 10B show the results of the observer's subjective evaluation regarding “whether or not the observer with his eyes closed can easily understand the change in the luminance of the illumination light”. The horizontal axis indicates the luminance ratio C1 with a logarithmic axis, and the vertical axis indicates the subjective evaluation value. As is clear from FIG. 10, the luminance ratio C1 is 10, and the subjective evaluation is 2 or more. Therefore, it has been found that when the luminance ratio C1 is larger than 10, an observer who closes his eyes evaluates that the change in luminance of the illumination light is easy to understand. From the above, in the respiratory adjustment period, the minimum luminance L per cycle of the periodic change of the illumination light _MIN1 Maximum luminance L for _MAX1 Luminance ratio C1 (= L _MAX1 / L _MIN1 ) Satisfies 10 <C1 in order to present “illumination light that allows an observer with closed eyes to easily breathe”.
[0061]
Next, in order to present “illumination light that makes it easy for an observer with closed eyes to fall asleep” during the adaptation period, the luminance that does not make the observer 30 with closed eyes feel uncomfortable under the experimental environment shown in FIG. Ratio C (L _MAX / L _MIN An experiment was conducted to determine the upper limit value. Each of the seven observers was asked to observe the illumination light 50 from the light source 10 while changing the luminance ratio C within a predetermined range, and was asked to answer the upper limit value of the luminance ratio C without feeling uncomfortable.
[0062]
FIG. 11 shows the experimental results. In FIG. 11, the horizontal axis indicates the luminance ratio C on a logarithmic axis, and the vertical axis indicates the probability (%) that the observer does not feel uncomfortable. Using the experimental apparatus shown in FIG. 7, “no discomfort” or “discomfort” with respect to the perception observed for a high range of ocular illuminance and ocular illuminance ratio under the same experimental conditions. Asked me to make a choice. The percentage of the number of people who answered “no discomfort” for each condition was calculated, and it was defined as the probability (%) of “no discomfort”. In other words, if 4 people answered “No discomfort”, 4/7 × 100 = 57%. From FIG. 11, even when the luminance ratio C increases, the observer who closed his eyes does not “feel uncomfortable” until the luminance ratio C reaches 15. When the luminance ratio C exceeds 15, the probability that an observer who has closed his eyes will not feel uncomfortable decreases monotonously. The probability that an observer who closes his eyes with the luminance ratio C is “not feeling uncomfortable” is 75%. When this curve is extrapolated, the probability that an observer who closes his eyes with a luminance ratio C of 50 feels “no discomfort” is less than 60%, and when the luminance ratio C exceeds 100, the probability is less than 50%. Therefore, it can be seen that the probability that the observer who has closed his eyes does not feel uncomfortable becomes 50% or more when both the respiratory adjustment period and the adaptation response period are C ≦ 100.
[0063]
From the above, the luminance ratio C2 in the adaptation corresponding period needs to be designed to satisfy C2 ≦ 100. Moreover, it is preferable that the luminance ratio C1 in the breathing adjustment period is also designed to satisfy C1 ≦ 100. Therefore, the luminance ratio C1 in the breathing adjustment period is designed to satisfy 10 <C1 ≦ 100, and C2 in the adaptation corresponding period is designed to satisfy 6 ≦ C2 ≦ 100.
[0064]
In addition, since the probability that an observer who closes his eyes when the luminance ratio C is 50 does not feel uncomfortable is 60%, the luminance ratios C1 and C2 are not to cause discomfort to more people. Are preferably designed so as to satisfy C1 ≦ 50 and C2 ≦ 50, respectively. Therefore, it is more preferable that the luminance ratio C1 is designed to satisfy 10 <C1 ≦ 50, and the luminance ratio C2 is designed to satisfy 6 ≦ C2 ≦ 50.
[0065]
Furthermore, since the probability that an observer who closes his eyes when the luminance ratio C is 30 does not feel uncomfortable is 75%, the luminance ratios C1 and C2 are not necessary in order to prevent more people from feeling uncomfortable. More preferably, the upper limit values of are designed so as to satisfy C1 ≦ 30 and C2 ≦ 30, respectively. Therefore, it is more preferable that the luminance ratio C1 is designed to satisfy 10 <C1 ≦ 30, and the luminance ratio C2 is designed to satisfy 6 ≦ C2 ≦ 30.
[0066]
In addition, since the probability that an observer who closes his eyes with the luminance ratio C is “not feeling uncomfortable” is 100%, in order not to cause discomfort to more people, the upper limit values of the luminance ratios C1 and C2 Are more preferably designed to satisfy C1 ≦ 15 and C2 ≦ 15, respectively. Therefore, it is even more preferable that the luminance ratio C1 is designed to satisfy 10 <C1 ≦ 15 and the luminance ratio C2 satisfies 6 ≦ C2 ≦ 15.
[0067]
5. Maximum brightness control
Next, control of the maximum luminance in the present embodiment will be described together with a human dark adaptation function.
[0068]
In general, changes in visual sensitivity due to dark adaptation are expressed by dark adaptation curves. FIG. 12 shows an example of the dark adaptation curve R. Humans cannot perceive light with a light amount below a certain limit value, and the light intensity at that limit is called a threshold value. The horizontal axis in FIG. 12 is the elapsed time from the start of adaptation, and the vertical axis shows the threshold value on a logarithmic scale. This means that the lower the threshold, the higher the visual sensitivity. Therefore, when the brightness of the illumination light is changed in the same form as the observer's dark adaptation curve R, the brightness of the illumination light always looks the same for the observer. As described above, even if the observer is in the closed state, the same applies if the luminance is equal to or higher than the threshold value in the closed eye state. In addition, as shown in FIG. 12, the dark adaptation proceeds abruptly for several minutes from the start, and generally proceeds from about 15 minutes to about 30 minutes after a pause.
[0069]
The dark adaptation curve R varies depending on the environment in which the same person adapts, that is, how much luminance is adapted. Moreover, it also differs depending on how much time and how much time there was before the adaptation started. However, as described above, adaptation continues until a time of at least 15 minutes and at most about 30 minutes has elapsed. Also, when adapting to a relatively low luminance, the sensitivity increases by about 10 to 100 times even after the first rapid progress is completed.
[0070]
In the present embodiment, the maximum luminance of the illumination light is decreased along the dark adaptation curve R in the adaptation response period so that the observer does not feel the illumination light dazzling. However, as described above, since the dark adaptation curve R is not uniquely determined, the dark adaptation curve in the present embodiment is defined as follows.
[0071]
In the present embodiment, the adaptation corresponding period in which the maximum luminance changes along the dark adaptation curve R is after the respiratory adjustment period and the transition period. Therefore, since it is considered that the progress of the first sudden dark adaptation is finished in the adaptation correspondence period, the subsequent increase in sensitivity is about 100 times at the maximum. The adaptation proceeds for a maximum of 30 minutes including the first sudden increase in sensitivity, and the subsequent sensitivity becomes constant. Therefore, the dark adaptation curve in the present embodiment is such that when the luminance value at the start of the adaptation corresponding period is L1, it decreases monotonously with time from the luminance value L1, is smaller than the luminance value L1, and is L1 / 100. A curve that is constant in the vicinity of the larger luminance value L2. Note that “decrease monotonically” means that it always decreases with the passage of time or takes the same value. Since adaptation proceeds for about 30 minutes at the maximum, the dark adaptation curve R in the present embodiment takes the luminance value L2 before 30 minutes have elapsed from the start of the respiratory adjustment period. A solid curve in FIG. 13 is an example of the dark adaptation curve R in the present embodiment. The dark adaptation curve R does not accurately represent the visual sensitivity of the observer (user), but by changing the maximum luminance along such a curve, compared to the case where the luminance is not changed, Obviously, the illumination light is less likely to feel dazzling, making it easier for the observer to fall asleep.
[0072]
However, if the decrease in maximum brightness is too rapid compared to the actual sensitivity, the brightness may be below a threshold that can be perceived in the closed eye state, and part or all of the illumination light may not be perceivable. Generally, since the increase in sensitivity proceeds at least about 10 times, the luminance value L2 is preferably L1 / 10 or more.
[0073]
Further, in the dark adaptation curve R of the present embodiment, it is only necessary to monotonously decrease from the luminance value L1 to the luminance value L2, and the shape is not particularly limited. FIG. 14 shows a specific example of the dark adaptation curve. For example, as shown by the curve A1, the luminance value L1 and the luminance value L2 may be connected by a straight line. On the other hand, since the perceived brightness is a logarithmic value of luminance, if the luminance is decreased by an exponential function, it appears to humans as changing at a constant pace. Therefore, an exponential function passing through the luminance value L1 and the luminance value L2 may be used as in the curve A2. Alternatively, it may be reduced after imitating the original dark adaptation curve shown in FIG. 12, taking a constant value for about 1 to 5 minutes as shown by the curve A3. Even in this case, a straight line or an exponential function may be used for the decreasing portion. These curves are preferred dark adaptation curves in practicing the present invention.
[0074]
As shown in FIG. 14, if the time from the start of the adaptation corresponding period is t (minutes) and the time required for the dark adaptation curve R to reach the luminance value L2 from the luminance value L1 is AT (minutes), Until the curve A2 reaches the luminance value L2 from the luminance value L1, L = L1 × (L2 / L1) ^{t / AT} It is expressed. In addition, a curve in which the luminance difference is within ± 10% from the above curve at a part or all of the time looks practically almost the same as the original curve. Therefore, such a curve is also a preferable dark adaptation curve in practicing the present invention.
[0075]
Furthermore, if it is a curve passing through a region sandwiched between the curve A2 and the curve A3 shown in FIG. 14, it is considered that there is no significant difference in appearance from the curve A1, the curve A2, or the curve A3. FIG. 15 shows a hatched area between the curve A2 and the curve A3 that linearly decreases after the luminance value L1 is 5 minutes. Maximum luminance L along a curve passing through this region _MAX Is also a preferable dark adaptation curve in practicing the present invention. In the hatched area in FIG. 15, the range of 0 ≦ t ≦ 5 is
L1 x (L2 / L1) ^{t / AT} ≦ L ≦ L1
The range of 5 ≦ t ≦ AT is
L1 x (L2 / L1) ^{t / AT} ≦ L
≦ L1- (L1-L2) × (t-5) / (AT-5)
Represented by
[0076]
6). Example of control
An example of the illumination light control method using the brightness ratio and the brightness control in this embodiment will be described with reference to FIG.
[0077]
The luminance ratio takes a constant luminance ratio C1 during the breathing adjustment period, gradually decreases during the transition period, and reaches a constant luminance value C2 smaller than C1. Thereafter, in the dark adaptation corresponding period, the maximum luminance L is maintained while maintaining the luminance ratio in one cycle at C2. _MAX2 Varies along the dark adaptation curve R. As described above, C1 may satisfy 10 <C1 ≦ 100, and C2 may satisfy 6 <C2 ≦ 100.
[0078]
Since dark adaptation proceeds during the breathing adjustment period and the transition period, L _MAX Is more preferable. In the example shown in FIG. 16, the maximum luminance L even during the transition period. _MAX Is decreasing. Maximum luminance L during the transition period _MAX For example, a linear decrease or an exponential function may be used as in the dark adaptation curve. Alternatively, a quadratic function or a cubic function may be used. Maximum luminance L not only during the transition period but also during the breathing adjustment period _MAX May be reduced. However, the maximum luminance L is not necessarily before the adaptation period. _MAX There is no need to reduce.
[0079]
Considering the actual sleep onset, a method of controlling the illumination light as a steady light after relaxation for a certain period of time is also considered. The steady illumination light referred to here is assumed to include zero light, that is, light extinction. FIG. 17A shows an example when the light is steady, and FIG. 17B shows an example of the illumination light when the light is turned off.
[0080]
7). Examples of more preferable control
Further experiments were performed to confirm the effect of the present invention and to find a more preferable control method. In the following description of the experiment, the illumination light will be described using the observer's eye surface illuminance. Further, the illuminance on the eye surface is achieved by controlling the luminance of the light source so as to be relatively the same.
[0081]
First, as an experiment on the adaptation response period in which the brightness follows the dark adaptation curve, an experiment equivalent to the experiment on the discomfort of the brightness ratio was performed by changing the observer's adaptation time for low illumination conditions. Seven observers were allowed to observe the illumination light with his eyes closed, and asked if the brightness of the illumination light felt uncomfortable. Although the illuminance ratio (luminance ratio) is only 10 times, this is just in the middle of the most preferable luminance ratio range, and is a value representative of the preferable luminance ratio range.
[0082]
FIG. 18 shows the result of the experiment. The vertical axis in FIG. 18 represents the probability (%) that the observer does not feel uncomfortable. A is the result with the maximum illumination intensity of 1 lx and the adaptation time of 5 minutes, B with the maximum illumination intensity of 1 lx and the adaptation time of 25 minutes, and C with the maximum illumination intensity of 0.1 lx and the adaptation time of 25 minutes. As can be seen from FIG. 18, the probability of “not feeling uncomfortable” was about 85% for A, 70% for B, and 100% for C. In addition, when the question “Whether breathing can be adjusted to the illumination light” was asked during the experiment, at least 85% or more of A, B, and C responded that they were able to adjust their breathing. did.
[0083]
As can be seen from FIG. 18A, the illumination light with the maximum illuminance of 1 lx is the illumination light that “not feels uncomfortable” with a probability of 85% in the state of adaptation for 5 minutes. When the lighting device of the present invention is actually used, it is considered that many users use it with such a large illuminance, and the effect of the illumination light “not feeling uncomfortable” is great with a probability of 85%. At that time, when the adaptation corresponding period is not provided, that is, when the same illumination light is continuously presented, the probability of “not feeling uncomfortable” decreases from 85% shown in A of FIG. 18 to 70% shown in B. On the other hand, when an adaptation period is provided and the illumination light is changed to illumination light having a maximum illuminance of 0.1 lx after 25 minutes, the probability of “not feeling uncomfortable” increases from 85% shown in FIG. 18A to 100% shown in C. .
[0084]
From the above experimental results, it is clear that the provision of the adaptation response period has the effect of increasing the probability that the observer will not feel uncomfortable. If the illuminance of the illumination light at the start of the adaptation response period is extremely low, there is a possibility that it cannot be perceived by an observer who has not progressed dark adaptation. From the above experimental results, if the maximum illuminance at the start of the adaptation response period is about 1 lx, the probability of “not feeling uncomfortable” is sufficiently high, and the rhythm of respiration can be matched to the change in illumination light. Since the illuminance depends on the distance between the light source and the observer, illumination light cannot be designed with strict illuminance even in this embodiment, but the illuminance at the distance normally used depends on the shape of the illumination device. It is possible to predict. For example, in the case of a ceiling light type lighting device, the luminance L1 is designed so that the illuminance is about 1 lx at a distance (about 2.5 m to 2 m) from a ceiling surface to a floor surface or a bed in a normal house. It is possible. Such illuminance design is generally performed even in a normal lighting device, and in this embodiment, it is preferable that the luminance L1 is designed so that the eye surface illuminance of the observer is about 1 lx. In addition, when the observer can change the position of the illumination device as described above, for example, in a stand-type illumination device for a bedside, the observer has a maximum eye surface illumination of about 1 lx at the start of the adaptation support period. It is thought that there are many cases where the device is arranged in the area.
[0085]
As described above, 1 lx is preferable as the maximum illuminance at the start of the adaptation response period, and it is expected that many observers will actually select it. In this case, it is preferable to design so that the “probability of feeling uncomfortable” does not decrease even when dark adaptation progresses after a sufficient amount of time has passed, at least as compared to the start of the adaptation response period.
[0086]
Referring to FIG. 18, when illuminating light having the same “probability of not feeling uncomfortable” of 85% after acclimatization for 25 minutes is assumed to be 85%, B having a maximum illuminance of 1 lx is 70% and C having a maximum illuminance of 0.1 lx. Is 100%, it is considered to be about 0.5 lx between B and C. Therefore, assuming that the maximum illuminance at the start of the adaptation period is 1 lx, the luminance L2 of the dark adaptation curve in the present embodiment is set to L1 / 2 or less, and if the maximum illuminance is changed to 0.5 lx or less, adaptation is supported. It is considered that the “probability of feeling uncomfortable” does not decrease compared to the beginning of the period. Therefore, as a design of L2 in the present embodiment, L2 is preferably set to L1 / 2 or less. As described above, since L2 is preferably L1 / 10 or more, more preferable ranges of L2 are L1 / 2 or less and L1 / 10 or more (L1 / 10 ≦ L2 ≦ L1 / 2).
[0087]
Next, in order to confirm the effect of the lighting control method of the present embodiment, a confirmation experiment of the sleep effect was performed. The illumination control method used in the experiment will be described with reference to FIG. FIG. 19 shows a change in luminance of the light source, and the luminance L1 is set to a luminance at which the observer's eye surface illuminance becomes 1 lx.
[0088]
In FIG. 19, the luminance ratio C1 = 15 in the breathing adjustment period and the luminance ratio C2 = 10 in the adaptation corresponding period. As the dark adaptation curve R, the curve A2 in FIG. 14 was used, and the period AT was 7 minutes. The respiratory control period is 45 seconds and the transition period is 135 seconds. Further, the maximum luminance at the start of the adaptation corresponding period is L1, the luminance ratio L2 is 0.3 × L1, the maximum luminance in the breathing adjustment period is 5 × L1, and the minimum luminance is 0.35 × L1. Further, the maximum value of the luminance is also decreased during the transition period, which decreases the maximum value of the luminance along a cubic function.
[0089]
The KSS method was used for evaluation of the sleep onset effect. The KSS method is a method for evaluating drowsiness by reporting items applicable to one's own state among 22 items representing the state of the observer such as “thought is dull”. Each item is given a score, and the average score of items reported by the observer is used for evaluation. The score corresponds to an evaluation value obtained by evaluating sleepiness on a scale from 0 to 7. The closer to 0, the smaller the sleepiness, and the closer to 7, the greater the sleepiness. Although the KSS method is a subjective evaluation, it has been clarified that there is a strong correlation with a physiological index for evaluating sleepiness. In the experiment, we asked the observer to evaluate the sleepiness twice before and after the observation of the illumination light, and examined the change.
[0090]
As a result of the experiment, the score after observation was larger than that before observation for all observers, and the average score before observation was 3.14, whereas the average score after observation was 5.04. Therefore, it can be seen that the drowsiness of all observers is increased by the illumination control method of the present embodiment. In addition, there is an evaluation item that is given a score close to the average score before the observation 3.14 is an evaluation item that is given a score close to the average score after the end. There is a "head is blurred" (5.10). For this reason, it is considered that the state of many observers has changed from the state where the body is not sluggish to the state where the head is blurry by the lighting control method of the present embodiment. From the above, it was confirmed that the lighting control method of the present embodiment has a hypnotic effect.
[0091]
8). Other variations
Modification examples of the lighting device and the lighting control device according to the embodiment of the present invention are shown in FIGS. The modification shown in FIG. 20 is an example in which a sensor 25 for detecting the awakening state of the observer is provided in the pillow part, and the modification shown in FIG. 21 includes the sensor 25, for example, the backrest part of the massage chair 40. An example provided in is shown.
[0092]
In each of the above modifications, the sensor 25 is connected to the control unit 20, and automatically stops the light emission of the light source 10 when it is determined that the observer has entered the sleep state from the awake state of the observer detected by the sensor 25. Then turn off. The sensor 25 acquires the brain wave data of the observer, for example. By analyzing the frequency of the acquired electroencephalogram data, the wakefulness level of the observer can be evaluated. For example, an α wave coming out from the back of the head is detected, and it is determined that the observer has entered a sleep state when the α wave has decreased. The sensor 25 may be configured to acquire, for example, electrocardiogram data. The arousal level of the observer can also be evaluated by frequency analysis of heart rate and heart rate fluctuation from the acquired electrocardiogram data.
[0093]
Like these modified examples, it is possible to detect the awakening state of the observer (user) and automatically turn off the light when it is determined that the user has entered the sleeping state. it can.
[0094]
【The invention's effect】
As described above, according to the present invention, the lighting period of the light source is sequentially divided into at least a respiration adjustment period and an adaptation corresponding period, and in the respiration adjustment period, the minimum luminance L in one cycle of the luminance change of the light emitting surface of the light source. _MIN1 Maximum luminance L for _MAX1 Luminance ratio C1 (= L _MAX1 / L _MIN1 ) Is substantially equal to a certain value, and the minimum luminance L in one cycle of the luminance change of the light emitting surface of the light source is controlled during the adaptation period. _MIN2 Maximum luminance L for _MAX2 Luminance ratio C2 (= L _MAX2 / L _MIN2 ) Is substantially equal to a certain value smaller than the luminance ratio C1, and the maximum luminance L _MAX2 Controls the light source so as to change along the dark adaptation curve R, so that an observer with closed eyes can easily adjust the rhythm of breathing according to the change in the amount of illumination light, and can easily fall asleep Make it possible.
[Brief description of the drawings]
FIG. 1 is a block diagram illustrating a configuration of a lighting device according to an embodiment of the present invention.
FIG. 2 is a diagram illustrating a state in which an observer observes illumination light from an illumination device while sleeping on a bed.
FIG. 3 is a diagram illustrating the principle of a lighting control method according to an embodiment of the present invention.
FIG. 4 is a diagram illustrating human visual characteristics.
FIG. 5 is a diagram illustrating human visual characteristics.
FIG. 6 is a diagram illustrating an example of a change over time of a luminance ratio of a light emitting surface of a light source based on an illumination control method according to an embodiment of the present invention.
FIG. 7 is a diagram showing an example of an experimental environment.
FIG. 8 is a diagram illustrating an experimental result of a time difference with respect to a luminance ratio.
FIG. 9 is a diagram illustrating an experimental result of a response rate with respect to a luminance ratio.
FIG. 10 is a diagram illustrating experimental results of subjective evaluation values with respect to luminance ratios.
FIG. 11 is a diagram showing experimental results of psychological probabilities with respect to luminance ratios.
12 is a diagram illustrating an example of a human dark adaptation curve R. FIG.
FIG. 13 is a diagram showing a dark adaptation curve R in one embodiment of the present invention.
FIG. 14 is a diagram showing an example of a dark adaptation curve R in one embodiment of the present invention.
FIG. 15 is a diagram showing a preferable range of a dark adaptation curve R in an embodiment of the present invention.
FIG. 16 is a diagram illustrating an example of a temporal change in luminance of a light emitting surface of a light source according to an embodiment of the present invention.
FIG. 17 is a diagram illustrating an example of a temporal change in luminance of a light emitting surface of a light source according to an embodiment of the present invention.
FIG. 18 is a diagram showing the relationship between the adaptation time for each illuminance on the eye surface and the “probability of not feeling uncomfortable”.
FIG. 19 is a diagram showing a specific example of a luminance change in an embodiment of the present invention.
FIG. 20 is a diagram showing a modification of the lighting device according to the embodiment of the present invention.
FIG. 21 is a diagram showing another modification of the lighting device according to the embodiment of the present invention.
[Explanation of symbols]
1 Lighting device
1a pedestal
1b Power line
10 Light source
10a Shading surface
10b Light emitting surface
20 Control unit
22 Dimming signal generator
24 Dimmable lighting device
25 sensors
30 observers (users)
40 beds or chairs
50 Illumination light
60 experimenters

Claims (11)

An illumination device comprising: a light source; and a control unit that controls the light source so that luminance of a light emitting surface of the light source periodically changes.
The control unit sequentially divides the lighting period of the light source into at least a breathing adjustment period and an adaptation corresponding period,
In the respiratory adjustment period, the luminance ratio C1 (= L _MAX1 / L _MIN1 ) of the maximum luminance L _{MAX1 to} the minimum luminance L _MIN1 in one cycle of luminance change of the light emitting surface of the light source is substantially equal to a constant value. And controlling the light source,
The adaptation in the corresponding period, to a small constant value than the luminance ratio _{C2 (= L MAX2 / L MIN2} ) is the luminance ratio C1 of the maximum luminance _LMAX2 to the minimum luminance _{L MIN2} in one period of the luminance change of the light-emitting surface of the light source The illumination device, wherein the light source is controlled to be substantially equal and the maximum luminance L _MAX2 changes along a dark adaptation curve R. The control unit sequentially divides the lighting period of the light source into at least the breathing adjustment period, the transition period, and the adaptation corresponding period,
In the transition period, the luminance ratio C3 (= L _MAX3 / L _MIN3 ) of the maximum luminance L _{MAX3 to} the minimum luminance L _MIN3 in one cycle of the luminance change of the light emitting surface of the light source changes from the luminance ratio C1 to the luminance ratio C2. The lighting device according to claim 1, wherein the light source is controlled so as to gradually become smaller.   3. The lighting device according to claim 1, wherein the range of the brightness ratio C1 is 10 <C1 ≦ 100, and the range of the brightness ratio C2 is 6 <C2 ≦ 100. The dark adaptation curve R is constant at a luminance value L2 that is smaller than the luminance value L1 and larger than L1 / 10 as the time elapses from the luminance value L1 at the start of the adaptation corresponding period. Is the curve
When the time from the start of the adaptation corresponding period is t (minutes) and the time required for the dark adaptation curve R to reach the luminance value L2 from the luminance value L1 is AT (minutes), 0 ≦ t <5 ,
L1 × (L2 / L1) ^{t / AT} ≦ L ≦ L1 is satisfied, and 5 ≦ t ≦ AT,
L1 × (L2 / L1) ^{t / AT} ≦ L
The lighting device according to claim 3, wherein the lighting device is a curve satisfying ≦ L 1 − (L 1 −L 2) × (t−5) / (AT−5).   The illumination device according to claim 4, wherein the luminance value L2 is L1 / 2 or less and L1 / 10 or more.   The illumination device according to claim 1, further comprising a sensor that detects an awakening state of the observer, and automatically stops emission of the light source when it is determined that the observer has entered a sleep state.   The lighting device according to claim 6, wherein the sensor acquires brain wave data of the observer and detects the awakening state of the observer.   The lighting device according to claim 6, wherein the sensor acquires electrocardiogram data of the observer and detects an awakening state of the observer. An illumination control device that controls the light source such that the luminance of the light emitting surface of the light source changes periodically,
Dividing the lighting period of the light source into at least a breathing adjustment period and an adaptation corresponding period,
In the respiratory adjustment period, the luminance ratio C1 (= L _MAX1 / L _MIN1 ) of the maximum luminance L _{MAX1 to} the minimum luminance L _MIN1 in one cycle of luminance change of the light emitting surface of the light source is substantially equal to a constant value. And controlling the light source,
The adaptation in the corresponding period, a constant value luminance ratio _C2 of the maximum luminance _{L MAX2} to the minimum luminance _{L MIN2} in one period of the luminance change of the light-emitting surface _{(= L} MAX2 _/ L _MIN2) is smaller than the luminance ratio C1 of the light source And the maximum luminance L _MAX2 is controlled along the dark adaptation curve R so as to control the light source.   The illumination control apparatus according to claim 9, further comprising a sensor that detects an awakening state of the observer, and automatically stops light emission of the light source when it is determined that the observer has entered a sleeping state. An illumination control method for controlling the light source so that the luminance of the light emitting surface of the light source in the illumination control device changes periodically,
The controller of the lighting control device
Dividing the lighting period of the light source into at least a breathing adjustment period and an adaptation corresponding period,
In the respiratory adjustment period, the luminance ratio C1 (= L _MAX1 / L _MIN1 ) of the maximum luminance L _{MAX1 to} the minimum luminance L _MIN1 in one cycle of luminance change of the light emitting surface of the light source is substantially equal to a constant value. And controlling the light source,
The adaptation in the corresponding period, a constant value luminance ratio _C2 of the maximum luminance _{L MAX2} to the minimum luminance _{L MIN2} in one period of the luminance change of the light-emitting surface _{(= L} MAX2 _/ L _MIN2) is smaller than the luminance ratio C1 of the light source And the light source is controlled such that the maximum luminance L _MAX2 changes along a dark adaptation curve R.

Images