JP2009266482A - Physiological information adaptive type illumination control system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a physiological information adaptive type illumination control system that adjusts an illumination level based on individual's physiological information and keep his/her state of consciousness appropriately. <P>SOLUTION: This is an illumination control system enabling illumination for a partial time zone of a day to be high level, which includes: personal illumination means 4 for adjusting an illumination level; a biological sensor 8 for sensing physiological information of that person; determination means 12 for determining a state of consciousness of the person from the sensed physiological information in at least two ranks, i.e., a proper level at which an arousal level is high and an improper level at which an arousal level is low; and illumination adjustment means 14 designed to make an illumination level at least when the determined state of consciousness is at the improper level to be higher than a standard value of an illumination level at the proper level so as to facilitate improvement of an arousal level of the person. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a lighting control system for physiological information.

  In recent years, the number of people who spend most of their daytime in the light environment such as offices has increased, and the influence of such light environment on biological rhythms such as sleep and awakening has attracted attention.

  In general, the illuminance setting in the office is generally about 750 lx in terms of the illuminance on the desk surface, but this illuminance is only based on whether an object looks appropriate.

  Among the periodicity of human physiological phenomena, a high arousal level when bright and a low awakening level when dark is called circadian rhythm, and it is known to measure this with a biosensor (Patent Document 1). Paragraphs 0004, 0010, etc.).

  In this specification, “arousal level” represents the degree of consciousness. Moderate tension suitable for work is “normal awakening”, excitement due to excessive stimulation and exercise, “excessive awakening” when overstrained, “low awakening” when tension is released due to fatigue or lack of sleep That's it.

Humans have long been active in the bright sunlight and have the above biological rhythm. This disruption of rhythm can cause a reduction in daytime arousal levels and nighttime insomnia.
From the above viewpoint, an office / circadian lighting system has been proposed that irradiates high-illuminance light with a desk surface illumination of about 2500 lx in a certain period of time, compared to conventional office lighting that has a constant illumination throughout the day (non-illumination). Patent Document 1).

A control method for detecting the illuminance and feeding back the detected value to the output of the illumination circuit in order to set the illuminance on the light receiving surface to a desired value has been conventionally known (Patent Document 2). Moreover, although it is not the invention regarding illumination, the technique which detects a motion of a body with an acceleration sensor and determines a dozing state (dozing driving) is known (patent document 3).
JP-A-5-3877 JP-A-11-233268 JP 2000-315287 A JP 2004-209126 A JP-A-8-299443 JP-A-4-269972 Matsushita Electric Works Technical Report Vol.53 No.1 “Psychological Effect of“ Circadian Lighting System ”for Offices” Kimiyuki Noguchi February 2005

The illumination system of Non-Patent Document 1 performs high-illuminance irradiation with a desktop surface illumination of 2500 lx in the morning for 2 hours (9:00 to 11:00) and in the afternoon for about 1 hour (12:40 to 13:40) ( The High condition and the remaining time zone are to perform normal irradiation with a desk surface illuminance of 750 lx (Low condition) This method is to uniformly control the interior of the room. Because it consumes more energy than lighting, it is questionable whether it is necessary for people who have enough sleep at night and have a high level of awakening during the day. Since it does not reflect the state of consciousness, there is a possibility of causing discomfort to individual physical environments and a decrease in productivity.
On the other hand, the applicant also considered performing high-illuminance illumination when the subject's dozing state was detected using the above-described acceleration sensor. However, since the eyes are closed in the dozing state, it is difficult to awaken the consciousness with a stimulus of high illumination intensity.
Accordingly, an object of the present invention is to propose a physiological information-compatible illumination control system capable of adjusting illuminance based on individual physiological information and maintaining a state of consciousness appropriately.

The first means is
Provided with a feedback control system for detecting the illuminance in a specific lighting area and adjusting the lighting output so that the illuminance becomes a predetermined value, and to increase the illuminance in some time of day A lighting control system capable of
A lighting means with adjustable lighting output for illuminating a personal lighting area;
An illuminance sensor for detecting the illuminance in the illumination area;
Control means for controlling the output of the illumination means so that the detected illuminance approaches the target value;
A biological sensor for detecting personal physiological information that changes in accordance with the illuminance in the illumination area;
Storage means capable of recording at least individual physiological information for each individual;
By comparing the physiological information detected by the biometric sensor with the physiological information data at the time of the normal awakening of the individual, the level of the individual's awakening is at least two levels of the normal awakening level and the low awakening level. Determining means for determining in
Illuminance adjusting means for automatically changing the target value of the control means according to the determined arousal level;
Have
In response to the determination by the determination unit, the illuminance adjustment unit is configured to set the target value of the control unit higher than the normal level and return the target value to the normal level after a predetermined length of high illuminance irradiation time has elapsed. ing.
This means proposes to determine an individual's arousal level from physiological information. Human autonomic nerves are divided into sympathetic nerves that predominate when stress such as tension and excitement occurs, and parasympathetic nerves that predominate when relaxed. These two superiority and inferiority appear as signs of various bodies. For example, when the waveform of an electrocardiogram as shown in FIG. 4 is Fourier transformed, its low frequency component (LF) and high frequency component (HF) are obtained, LF is the activity of the sympathetic nerve, and HF is the activity of the parasympathetic nerve. It is well known that it is an index of When the wakefulness level is reduced by detecting the LF / HF value in the automobile doze prevention device of Patent Document 5, the game machine of Patent Document 4 displays the physiological information (blood pressure, pulse rate, body temperature, etc.) of the operator. When it gets too excited when it is detected, a warning is issued. Furthermore, the stimulus presentation device disclosed in Patent Document 6 detects physiological information such as human body movement, respiration, and heartbeat, and gives a stimulus of sound and vibration. However, these generate a warning signal when the state of consciousness estimated from physiological information becomes abnormal. This means is not just a warning, but applies a control system that performs high-illuminance lighting during a part of the day to a person whose arousal level is low based on personal physiological information. Is possible.
The “feedback control system” is used to keep the illuminance of the illumination area constant. In air-conditioning systems and the like, feedback control is used to eliminate the influence of disturbances and keep the room temperature constant, but such control is rare in an illumination system. In office lighting or the like, it is sufficient to set the lighting output to at least ensure a certain illuminance, and even if there is a disturbance (for example, natural light incident from a window), there is no particular problem. However, the present invention aims to detect physiological information in relation to illuminance and promote human arousal, and at that time it is a premise of the invention to keep the illuminance in the illumination area constant including disturbances. It is.

  “Physiological information” refers to information on physiological phenomena. Physiological phenomena refer to various phenomena that appear as living phenomena of living organisms and that appear mainly regardless of human intentions. For example, heart rate, LF / HF described later, blood flow, body surface temperature, cortisol in saliva, hemoglobin amount, and the like. In the present invention, an action based on the intention of a person is used to evaluate physiological information separately from physiological phenomena. Those that occur unconsciously like the blink of the eyelid, but those that can be consciously included are included in the physiological phenomenon.

  The “storage means” stores at least individual physiological information for each individual. “For each individual” means that each person is distinguished when a plurality of persons are targeted, and such a distinction is not necessary when only one person is targeted. The “physiological information” includes a physiological information threshold in addition to physiological information at each time. The storage means is preferably a database that associates physiological information itself with related information such as the time (or time segment) at which the physiological information is collected, and can select and extract information as necessary.

The “determination means” determines the arousal level of the subject based on the known physiological information in two stages: a level higher than normal awakening and a low awakening level. The reason why normal awakening and over-awakening are not distinguished is because the theme of this means is to promote awakening by increasing the illuminance. The process of transitioning from normal awakening to low awakening can be divided into three or more multi-steps, and a control method can be adopted in which the target value of illuminance is sequentially increased.
As shown in Table 1, the physiological information shows different values between awakening (when the eyes are clearly awake) and sleeping, but this numerical value has a large individual difference. Therefore, the determination is made based on the physiological information data at the time of normal past awakening of the individual. In addition, since it is rare to become over-awakened in a normal workplace, information excluding physiological information when activity level is low among all collected physiological information may be referred to as “physiological information at normal awakening”. it can.
The method for comparing the detected physiological information with the physiological information at the time of normal awakening includes a method for directly comparing the two and a method for comparing the two indirectly. As the former, for example, there is a method of calculating a threshold value between normal wakefulness and low wakefulness from physiological information at normal wakefulness measured for each time segment, and comparing this threshold with the measured physiological information. Further, as the latter, there is a method of statistically testing whether there is a significant difference between a past physiological information group and a newly measured physiological information group. Details will be described later.

The “illuminance adjusting means” changes the target value of the control means of the feedback control system in accordance with individual physiological information. In other words, the control means of the feedback control system is the first control device, and the illuminance adjustment means is the second control device, and the first and second control devices cascade control the entire lighting system. Yes. The illuminance adjusting means can adjust the illuminance in three stages of zero illuminance (illumination off), low illuminance, and high illuminance. The change of the target value from the low illuminance to the high illuminance may be automatically performed, but may be performed by the user himself / herself or another person's command. As a method for adjusting the illuminance, when it is determined that the wakefulness level is lowered, time control is performed for maintaining a high illuminance for a certain time, for example, about 20 minutes. The reason for this is that if the illuminance is made to follow the physiological information completely, as will be understood from an experimental example described later, when the user is depressed in the office, the awake state and the non-awake state are repeated at a short interval of about 1 minute. This is because there is no point in making the lighting brighter or darker each time.
As a preferred example, the illuminance adjusting means rapidly increases the illuminance of the illumination area at a speed at which a change in light and darkness is perceived by a person, maintains the illuminance for a certain time, and then returns to the original illuminance level. Can be formed. It means that the illuminance is increased rapidly from several seconds to several tens of seconds. In contrast to the control that switches on / off the sound and light of a normal alarm device instantaneously, in the present invention, as shown in FIG. 3, the output is increased or decreased in proportion to the elapsed time (lamp control). It is preferable to adopt a control method that gradually increases and decreases the output.
The second means includes the first means, and further includes an action detecting means for detecting an individual action in an illumination area also serving as a work place, and an analyzing means for analyzing physiological information,
The analysis means evaluates the activity level of the individual from the detected action, and forms the value of the physiological information when the activity level is high to be stored in the storage means separately from the physiological information when the activity level is low,
The wakefulness level is determined by using the physiological information when the activity level is high as the physiological information at the time of normal past awakening of the individual.
This means relates to a technique for associating physiological information collected by a biological sensor with an individual's arousal level. For this association, as described above, physiological information at the time of normal awakening may be collected as a threshold value, but this means proposes a configuration for automatically updating the numerical value. In other words, in the workplace, a state of consciousness, for example, a state where the user is actively moving by hitting the keyboard or making a phone call is regarded as normal awakening, and physiological information in that state is accumulated and accumulated. From the data, the threshold of physiological information at the time of normal awakening and at the time of normal awakening is obtained. Strictly speaking, the reason for saying "normally awakening" is that it may be picked up as physiological information such as the state that the heart rate is rising just after returning from going out only under the above conditions. is there. However, since it is rare that a state of over-awakening appears in a normal workplace, taking an average value of a large amount of data does not cause a problem in practice.

  “Personal movement” refers to body movement (body movement) performed mainly reflecting the intention of the person. These include hand and head movements and eye movements for work.

  The “motion detection means” refers to a device that can widely detect motion, and includes a non-contact position sensor using infrared rays or the like in addition to an acceleration sensor or the like. The limitation of “in the lighting area that also serves as a workplace” is meant to exclude operations during commuting or going out. This is because, under such conditions, physiological information can be collected in a normal workplace excluding the state of over-arousal.

 “Activity” is a concept representing the frequency or magnitude of human movement. The problem is how to define high / low activity, but in the present invention, when the individual is clearly in a state of consciousness higher than normal arousal, it is defined as “high activity”, otherwise It is sufficient if “activity is low”. This will be described later.

The “analyzing means” analyzes physiological information, for example, by extracting LF / HF from electrocardiogram data. Further, it has a function of evaluating the activity level from the motion information and distinguishing physiological information in a low activity level from physiological information in a high activity level.
The third means includes the second means, and the illuminance adjustment means is replaced with a configuration in which the target value is automatically changed according to the determination by the determination means.
In response to the above determination, an alerting section that informs of a decrease in arousal level,
An input unit that allows an individual to input an illuminance increase command;
The target value of the control means is changed in accordance with the input of this illuminance increase command.
By doing so, it is possible to respect each individual's willingness to use the lighting system of this system, and it is also expected to enhance the arousal effect by pressing the switch for increasing the illuminance command etc. .
The fourth means includes the second means or the third means, and the biological sensor detects the heartbeat of the person as the information of the electrocardiogram format together with the time to beat,
The determination means performs a Fourier transform on the heart rate data to extract a high frequency component (HF) and a low frequency component (LF), and the ratio of the high frequency component to the low frequency component (LF / HF) is normally awake. It is designed to determine a low arousal level when it is higher than (LF / HF) data of individual.

This means proposes to use electrocardiogram-like information obtained from the heart rate as physiological information. As described above, when the waveform of the electrocardiogram is Fourier transformed, its low frequency component (LF) and high frequency component (HF) can be obtained. Since LF is related to the activity of sympathetic nerves and HF is related to the activity of parasympathetic nerves, LF / HF can be used as an indicator of a decrease in arousal level, as already described. More specifically, LF is affected by both sympathetic nerves and parasympathetic nerves due to fluctuations mainly related to blood pressure regulation function, and HF is mainly related to parasympathetic nerves due to fluctuations caused by respiratory activity. It is said that there is. In evaluating the level of sympathetic and parasympathetic activity, it is important to pay attention to heart rate variability, but this measurement value evaluates the activity of the sympathetic nerve that controls the heart. It is desirable to evaluate the activity of sympathetic nerves that control blood vessels based on, for example, blood flow, blood pressure, body temperature, etc., and consider consistency with them.
The fifth means includes any one of the second means to the fourth means, and the illuminance sensor is attachable near the head of the individual,
In its attached state, while orienting the light receiving surface of the illuminance sensor in front of the person's vertical viewing angle,
A light shielding hood that blocks light from directions other than the front is attached.
In general, the illuminance on the desk surface is used to represent the illuminance in the office. Recently, however, many people work while facing the screen of a personal computer. The illuminance on the desk is mainly the light from the lighting means installed on the ceiling, while the light entering the eyes of the person facing the computer screen is mainly from the computer screen. Light is subordinate. Therefore, the present applicant has devised the use of a face sensor attached to a frame of glasses as a suitable example of the illuminance sensor.

The invention according to the first means has the following effects.
○ Since high-illuminance lighting is performed based on personal physiological information, the level of awakening during the day can be increased according to the personal rhythm.
○ Because light is used as a means of awakening consciousness, it does not hinder the work of surrounding humans compared to sound and vibration.

According to the invention relating to the second means, since the arousal level is determined based on information on an action performed by a human intention, a more accurate determination can be made.
According to the invention relating to the third means, since the person performs an operation for awakening, there is no sense of compulsion.

According to the fourth aspect of the invention, since the ratio of LF and HF is used as physiological information, a highly reliable determination can be made.
According to the fifth aspect of the invention, since the illuminance sensor receives light having a vertical viewing angle, the illuminance can be accurately controlled.

  1 to 14 describe a lighting system according to the first embodiment of the present invention.

  This system includes an illumination unit 2, an illuminance sensor 4, a control unit 6, a biological sensor 8, an analysis unit 12, a storage unit 14, a determination unit 16, and an illuminance adjustment unit 18.

The illumination means 2 is set for each individual. Each illumination means can adjust the illuminance of an individual workplace. In the illustrated example, light is emitted from directly above a person, but the illumination means can be set so as to emit light from the front of the face, for example.
The illuminance sensor 4 detects the illuminance of the individual workplace and outputs the detected value to the control means. The illuminance sensor may be attached to a fixed place near the work place such as a desk surface, but in the example shown in FIG. As a result, the illuminance of the face can be measured, and input data close to the brightness perceived by the individual can be obtained. Furthermore, the illuminance sensor 4 in the illustrated example projects a light shielding hood 5 that widens forward from the rear side of the light receiving surface with the light receiving surface facing forward. As shown in FIG. 6, the light shielding hood 5 is formed so as to block incident light from directions other than the vertical viewing angle of the person. The inclination angle θ ₁ of the upper wall of the hood 5 with respect to the horizontal direction is 60 °, the inclination angle θ ₂ of the lower wall of the hood with respect to the same direction is 70 °, and the inclination angle θ ₃ of the left and right walls of the hood with respect to the horizontal direction is 65 °. . But you may use what omitted the food | hood from the said structure. In FIG. 7, the graph which shows the time-dependent change of the illumination intensity measured with the illumination intensity sensor 4 with a hood in the below-mentioned experimental example is shown. In this graph, substantially flat peaks appear around 10:00 to 10:20, 11: 00 to 11:20, 13:10 to 13:30, 15:00, 16:10 to 16:30, This reflects the fact that high-intensity illumination was performed at each time. It is considered that the peak of each peak is a function of feedback control. The illuminance (face illuminance) observed over time varies slightly, which is understood to be due to the amount of light entering the face changing depending on the posture of the subject. The large increase in illuminance between 12:00 and 13:00 was due to sunlight or the like during the break, and is assumed to be unrelated to the illumination of this system.

  The control means 6 performs feedback control so that the illumination output is small when the detected illuminance is smaller than the target value, and is large when the detected illuminance is larger than the target value. This target value is input from the illuminance adjusting means described later.

  The biosensor 8 detects personal physiological information. The biosensor according to the present embodiment detects a heart pulse and has a known configuration. Such a sensor is a biological electrode that can be attached to the human chest, and detects an electrical signal of the human body (ventricular pulse voltage waveform generated from the heart) with high sensitivity. This signal may be amplified by an electrocardiograph (not shown), noise may be removed, and a digital signal may be converted into an electrocardiogram. It should be noted that when a person leaves a person's seat and sits down again, it is desirable to exclude physiological information for a certain period of time from the memory. This is because the heart rate increases more than usual by exercise such as walking. If such data is accumulated in the storage means, the average value of physiological information may be shifted.

The analysis means 12 first analyzes the data of the individual's electrocardiogram format. A wave having the largest spike shape in the waveform of the electrocardiogram as shown in FIG. 4 is referred to as an R wave, and an interval between the R wave and the R wave is referred to as an RR interval (see FIG. 4).
The main function of the analyzing means 12 is to take out the RR interval variation from the electrocardiogram data, extract the high frequency component (HF) and the low frequency component (LF), and obtain the ratio. When the RR interval variation is Fourier-transformed as conventionally known, two peaks appear on the high frequency side and the low frequency side in the graph (power spectrum) in which the horizontal axis represents frequency and the vertical axis represents intensity. A high-frequency component (HF) and a low-frequency component (LF) are obtained by taking integrated values of the intensity in two frequency sections including each peak. (LF / HF) is effective as an index representing the daytime arousal level. This index is output to the determination means and the storage means for each fixed time segment. In addition, when the parasympathetic nerve is dominant (when relaxed), phenomena such as a decrease in heart rate, an increase in the RR interval, and a large increase in variation in the RR interval appear. You may make it output such information for every time division as auxiliary information. However, when the physiological information can be used without being analyzed, the analyzing means can be omitted.
Further, as a subordinate function of the analysis means, it is preferable to perform an analysis necessary for the subsequent determination work such as a threshold of normal awakening and low awakening. When calculating the threshold, the physiological time and activity are collected by dividing the observation time into certain time segments, and every remaining time segment except for the time segments when activity is low from all time segments. What is necessary is just to obtain | require the lower limit of physiological information, and let the average value of those lower limits be a threshold value. Further, the analyzing means may present a threshold candidate value to a person, and the person may determine the threshold from the presented numerical value. The case of performing statistical processing instead of the threshold will be described later.

  The memory | storage means 14 has memorize | stored the threshold value of the physiological information of the normal awakening at this time for every individual. Further, the storage unit 14 creates a database in which physiological information for each time segment input from the analysis unit is associated with related information such as illuminance within the segment. With this function, for example, physiological information in an arbitrary time period of the day can be extracted.

  The determination unit 16 compares the physiological information threshold value output from the analysis unit 12 with the physiological information of each time segment to determine whether the level is low arousal. When a threshold value is normally set for a variable with a large variation such as LF / HF, there is a possibility that a warning display is displayed all the time. In order to avoid this, for example, a warning display may be displayed when the value falls below a threshold value a plurality of times (for example, twice) in units of time segments. Further, a statistical method such as a T test described later may be used. However, since the tension may be in a relaxed state during the holidays, this determination is made only during working hours. The determination means outputs a determination signal to the illuminance adjustment means when it is determined that the individual is in a low arousal state.

The illuminance adjustment means 18 outputs the target value of illuminance to the control means 6 according to a predetermined procedure in accordance with the determination signal from the determination means 16. At this time, the illuminance adjusting means may be configured to automatically transmit the target value immediately upon receiving a caution signal. However, in the preferred embodiment, the illuminance adjusting means 18 A stimulating unit 20 and an input unit 22 are provided, and the illuminance is increased after waiting for a user's command.
The alerting unit 20 alerts the user when a decrease in the arousal level is detected. There are various methods, but in an office environment such as this embodiment, for example, the screen of a personal computer used by the user says “The level of arousal is decreasing. Do you want to brighten the lighting? Yes NO” You may make a recommendation. Then, the command may be input by operating the input unit 22 which is a computer interface (mouse or keyboard).
As a modification, in the lighting of a truck driver's seat or the like, a similar recommendation may be made by voice and a command may be input from the input unit 22 which is a driver's seat switch. You may be alerted with a buzzer or lamp when working in a factory.
In each of the above cases, the alerting unit 20 repeatedly pays attention at a certain time interval when there is no user response to the attention. Then, when there is no response from the user at all for a second (or series of) attention, it is possible to determine that the awakening level has fallen to such an extent that the user cannot respond, and to automatically increase the illuminance.
The illuminance adjusting means is configured to return the target value to the original illuminance when a predetermined time has elapsed. The normal illuminance is preferably 750 lx, and the illuminance at high illuminance illumination is 2500 lx. Specifically, when the illuminance increase command is issued, the illuminance adjusting means increases the normal illuminance level Lx1 to the high illuminance level Lx2 over time of Δt1 as shown in FIG. Then, during T, after maintaining the illuminance at Lx2, it takes Δt2 and returns to the original illuminance level Lx1. In a preferred example, Δt1 = Δt2 = 1 minute and T = 20 minutes. When a stimulus such as light is used as a warning means, the stimulus is usually canceled after the other party is awakened, whereas the present invention maintains a high illumination state even after awakening. This is because the purpose is to adjust the disturbance of the rhythm of the living body while working in a high illumination state. In a more preferred example, Lx1 = 600 lx and Lx2 = 2500 lx. These values can be changed as appropriate, but the Lx2 values should be within the range that does not interfere with normal work.
The analysis unit 12, the determination unit 16, and the illuminance adjustment unit 18 can be configured by a computer.
FIG. 8 is a flowchart showing the main part of the flow of illumination control by this system. The control flow for maintaining the illuminance at the reference value (Lx1) by the control means is a normal feedback system control, and is therefore omitted. The control method shown in the figure is semi-automatic to increase the illuminance after waiting for the user's command, and is time control to increase the illuminance for a certain time regardless of the arousal level when the command is issued. However, as described above, it can be a fully automatic system, or instead of time control, physiological information can be fed back to the input side of the illuminance adjustment means so that high illuminance continues until the wakefulness level returns to normal wakefulness. Is possible. The process of raising the illuminance and returning the illuminance after a certain time is performed in a constant control cycle.

  When this system is used, physiological information corresponding to the threshold values of normal wakefulness and low wakefulness is determined in the initial use when the system is applied to an individual. For this purpose, only the physiological information of the person is collected without the displacement of the physiological information being linked to the illuminance. The simplest way to do this is to exclude time categories where physiological information tends to fluctuate compared to normal working hours, such as immediately after returning from work or after returning from work. May be used. Moreover, you may test an individual's physiological information at the time of normal awakening irrespective of this system. A method for mechanically setting the threshold will be described later.

According to the said structure, a light environment can be kept appropriate according to a user's physical condition and biological rhythm. It is also expected to increase nighttime awakening levels and prevent nighttime insomnia.
[Experimental example]
In order to measure the effect of the present invention, comparative experiments were performed in the three situations shown in FIG.
Case 1 is an illumination method that provides a normal level of illuminance. From 8 am to 8:30 am exposed to sunlight during commuting hours, the ceiling surface illumination is set to 5000 lx, and the ceiling surface from 7 am to 8 am and from 8:30 am to 9 pm The illuminance is 500 lx. The ceiling surface illuminance is illuminance measured by a sensor installed on the ceiling surface. Although the luminaire is installed on the ceiling surface, the illumination on the ceiling surface is smaller than the illuminance on the desk because it mainly emits light downward.
Case 2 is a conventional circadian illumination system that performs high illumination illumination during a predetermined time of the day. Compared with Case 1, high illuminance is applied between 8:30 am to 12:00 am and 1 pm to 2 pm. The ceiling surface illuminance in the meantime is 2500 lx. In order to see the effects of high-intensity irradiation over the course of several days, the same person was tested for two days.
Case 3 is an illumination method according to the present invention in which the system is instructed to perform high-illuminance illumination when it is determined that the subject has become sleepy. The time of high illumination irradiation is 5 minutes. The output of the lighting fixture can be selected from 100%, 70%, and 50% with the ceiling surface illumination of 2500 lx as the upper limit. Similarly to Case 2, the same person was tested for 3 days.

  The subjects of the experiment are body surface temperature T, electrocardiogram and LF / HF obtained therefrom, heart rate (referred to as “beat rate” in the table), RR interval (referred to as “CV”), and the like.

  The experimental conditions are as follows. First, subjects whose sleep time was 6 hours or less were used as subjects. Here, data for one subject is shown. The illuminance sensor uses a sensor 4 shown in FIG. The measurement interval with this illuminance sensor is 40 Hz. Case 1 was measured for 1 day, Case 2 was measured for 2 days, and Case 3 was measured for 3 hours for 24 hours at 1 minute intervals.

Among the above three cases, Case 3 LF / HF corresponding to the present invention is shown in FIG. 10, Case 3 heart rate is shown in FIG. 11, and Case 3 HF is shown in FIG. The time period when the data in these charts is missing is the time when the data could not be obtained due to going to the toilet.
In the experiment, as shown in Tables 2 and 3, various physiological information was measured every minute. Data for Case 1 and Case 2 are shown in Table 2, and data for Case 3 are shown in Table 3, respectively.

  As described above, the LF / HF when waking up is about 4.9 ± 0.9, and that during sleep is about 1.7 ± 2.7. When this is applied to the Case 1 data, it can be seen that the consciousness has gone back and forth between the awake state and the sleep state for 25 minutes, and is in a state of being depressed. The heart rate and LF / HF are not exactly the same, but when the heart rate peaks, LF / HF also peaks before and after that.

Table 3 shows the data collected by the method of the present invention. This table only shows that the data was taken mainly in this manner, and is not shown for comparison with the normal illumination and conventional cardian illumination in Table 1. Even if the size of physiological information is compared using various methods at the same time, a significant result cannot be obtained simply because fatigue occurs at that time. In order to make a meaningful observation, it is necessary to look at a time average over a certain length, which will be described later.
FIG. 13 shows a summary of the results of this experiment, in which the values of LF / HF were tabulated and averaged every sufficient interval. According to Table 1 described above, LF / HF is about 4.9 ± 0.9 when waking up and 1.7 ± 2.7 during sleep. Therefore, a numerical value with LF / HF of less than 4 is considered to be a low arousal state, and particularly a numerical value of less than 3 is surrounded by a thick frame in the figure. In each time section, one * is given for 5 minutes of high illuminance irradiation, and two * are given for 10 minutes of high illuminance irradiation.
The results shown in FIG. 13 are further tabulated in the following Table 4. This is a count of how many times a low arousal state appears in a 10-minute time division unit. In case 1 of normal lighting, events with LF / HF of less than 4 appear 21 times, whereas in case 2 of conventional circadian lighting, the same events are 11 times and 14 times on both days. There is a considerable improvement. Further, in Case 3, which is the illumination method of the present invention, the same event appears 13 times on the first day, 6 times on the second day, and 7 times on the third day. That is, the first day is almost the same as Case 2, but further improvement is seen on Case 2 and Day 3 compared to Case 2.

Returning to FIG. 13, in Case 1, which is a normal illumination, a clearly low arousal state can be seen in the time zone from 9 o'clock to 10:30 and 1 o'clock to 4 o'clock. In Case 2, which is a uniform high illumination, the awakening state is improved in the afternoon time zone. However, there remains a tendency to be suddenly drowsy after a high arousal state to some extent. Although this has a wakefulness effect by high illumination, it seems that it will be in the state when high illumination continues for a long time, and it will be attacked by sleepiness. In the case of the lighting method according to the present invention, the first day test among the three consecutive days is the same as Case 2, but the awakening level is improved on the second and third days. The following reasons can be considered for this.
First, as a result of raising the level of awakening during the day with high-illumination irradiation on the first day, it was possible to sleep well at night, and the awakening state during the day after the next day was improved. . Comparing the numbers in the first half of 9 am to the evidence, the first day is 2.67 and 2.03, while the second day is 6.43, 7.45 and the third day is 3.91, 4. .65. Compared to the first day, the second and third days are better awakened. It is appropriate to interpret the good state of morning awakening as the difference in sleep quality of the previous day rather than the effect of high-intensity lighting on that day.
Secondly, it is thought that the subject's own awakening action is increased by pressing the switch, and at the same time, the user has learned how to press a suitable switch as time passes. In Case 3, the subject feels strong sleepiness in, for example, 10:00 to 10:09 and 14: 0 to 14:09, but never presses the switch for increasing the illuminance command in this time segment. This is because it is impossible to press the switch after being attacked by strong sleepiness with an average value of LF / HF of less than 3. It is important to press the switch when you feel a little sleepy before that happens.
For example, one * is attached to the time section of 1:30 to 16:30 to 16:39. The LF / HF for this time segment is 7.1, and the LF / HF for the previous segment is 5.56. At first glance, this number usually seems to be awake. However, this number is an average value, and when viewed in units of 1 minute, sleepiness with LF / HF of about 2 to 4 is temporarily attacked. Even if you think you just fell asleep for a moment, you need to press the switch as soon as the warning message appears. It seems that the reason why the good arousal state is obtained in the afternoon in Case 3 is due to such a preferable use method. Where there is an asterisk (*), a decrease in LF / HF is observed immediately before that, and it can be seen that the subject feels momentary sleepiness, although the average value is not known.
Next, in Case 3 according to the present invention, the number of times of performing high illumination illumination is shown in Table 5 below. Irradiation was performed 38 times on the first day, 25 times on the second day, and 16 times on the third day. Since the irradiation time for one time is 5 minutes, the irradiation time for the day is 190 minutes on the first day, 125 minutes on the second day, and 80 minutes on the third day. In Case 2, irradiation is performed for 240 minutes with a ceiling surface illumination of 2500 lx (same as 100% output of Case 3). In Case 3, the irradiation time is shorter than in Case 2, and the irradiation output per unit time is small over a considerable time. Therefore, it can be seen that the irradiation energy in Case 3 is smaller than that in Case 2.

FIG. 14 shows a comparison of LF / HF and HF during sleep on the third day of Case2 and Case3. It can be seen that HF is higher in Case 3, and thus good sleep is obtained.
From the above experimental results, it can be seen that there is room for improvement in the method of this experiment. For example, when a low arousal state in which the average value of LF / HF is less than 3 is detected, it is desirable to automatically perform high illumination irradiation without waiting for the subject to press the switch. It is also conceivable to install another light source not only from the ceiling but also almost perpendicular to the face. Even if there is such a point to be improved, the Case 3 method of the present invention is equivalent to the Case 2 method while reducing energy consumption, and depending on the conditions, it exhibits more daytime awakening and nighttime sleepiness. The possibility was shown.
[Example 1]
The use of the T test as one of the methods for statistically determining the arousal level will be described. T-test is a determination of whether there is a significant difference in the mean values of two populations. In the present invention, one of the two groups is measurement data (determined group) of physiological information over a certain length of time period of an individual on the day of implementing the present invention. The other is the same physiological information data (population) recorded before the implementation date for the individual. For a variable such as LF / HF having a large variation with time, good control can be performed by a statistical method.
The method of the test is slightly different depending on whether the information distribution of the two groups is the same. Since this method is known, it will be briefly explained. When the variances are the same, the two groups to be compared are X1... Xn and Y1... Yn, and first the sample averages X ^* and Y ^* of both groups and the unbiased variance are used. Find U _X and U _Y. Next, an estimated value Ue [= {(m−1) U _X + (n−1) U _Y } / (m + n−2)] of both groups is calculated. From this, the test statistic {t ₀ = | X ^* −Y ^* | / {Ue (m ⁻¹ + n ⁻¹ )} is calculated. The ρ value on the upper side of t zero in the t distribution with the degree of freedom v = m + n−2 is obtained and compared with the significance level α. If ρ <α, there is a significant difference in the average of both groups.
That is, the arousal level is lower than the average of past measurement data. In this embodiment, since the present information group is tested against past information and a significant difference is verified, the reliability is high. It is assumed that there is a certain amount of information accumulated. It is desirable for the population to use all physiological information measured in the past, excluding physiological information during low arousal. As the method, physiological information at the time of low arousal can be excluded based on the activity level of a person as in the preferred second embodiment. However, as a simpler method, for example, among all measured physiological information, the time zone immediately after 9 o'clock in which the normal awakening situation is bad and the time zone around 14:00 may be omitted and the remaining time zone may be regarded as the normal awakening state. . When the above procedure is applied to the configuration of the present invention, the analysis means 12 calculates the sample mean and unbiased variance of each group, calculates the variance value of both groups, and determines the ρ value, and the determination means 16 determines the ρ value and significance level. Compare with the above.

15 and 16 show a system control method according to the second embodiment of the present invention. In this embodiment, in parallel with collecting biological information from an individual, the threshold of the physiological information is automatically detected based on physiological information of a time segment in which the movement of the individual is detected and the operation is evaluated to be active. The content is to update.
The illumination system according to the present embodiment includes an operation detection unit 10. The motion detection means may be an acceleration sensor that can be worn at an appropriate place on the human body. The wearing place may be a place in the human body that has a large movement at normal awakening and a small movement at low awakening. In the example shown in the figure, the wristwatch is attached to the wrist. Further, instead of the acceleration sensor, for example, a cushion-shaped air cell and a detecting means (pressure sensor) for detecting the air entering and exiting the air cell may be provided, and the weight shift of the seated person may be detected.
The analysis unit determines the activity level from the measurement value detected by the motion detection unit 10. As a suitable example, it can be determined by the number and frequency of unique movements at normal awakening. For example, a typing operation detected by an acceleration sensor, an operation of waking up from a chair, or the like detected by a cushion-type pressure sensor. When such an operation does not reach the predetermined number and size, it may be determined that the activity level is low. What is necessary is just to select physiological information in a state where it is certain that the eyes are awake, and to use it for calculation of a threshold value for determining the arousal level.

And in this embodiment, the analysis means 12 receives the acceleration information from the motion detection means 10, and calculates the magnitude | size of an acceleration for every fixed time interval. The analysis means 12 evaluates that the activity level is high when the magnitude of acceleration in each time segment exceeds the reference value, and that the activity level is low when the acceleration value does not exceed the reference value. This evaluation is input to the storage means as related information in association with physiological information of each time segment.

  Furthermore, the analysis means 12 extracts the lower limit value of the physiological information of the time segment when the activity level is large from the storage means 14 for every fixed control cycle. Then, an average value of these lower limit values is calculated as a threshold value and returned to the storage means 14. In the storage means, the new threshold value is overwritten on the old numerical value.

  In the above configuration, during initial use, physiological information during normal awakening may be collected on a trial basis as in the first embodiment, and this may be used as the initial threshold value. Then, while using the system, data of physiological information when the activity level is large is accumulated, and the threshold value is sequentially updated.

FIG. 16 is a flowchart of the system according to the second embodiment. One of the features of the system is that it handles two variables, physiological information and activity.
[Example 2]
As the motion detection means 10, various conventionally known body motion sensors can be used. In addition, an infrared sensor installed in a suitable place such as a ceiling may detect a state in which an individual has moved a certain amount or more from a certain seat. Further, it may be detected that a computer operator inputs information to a keyboard or a mouse.

  FIG. 17 shows a system control method according to the third embodiment of the present invention. There are individual differences in the body's response to increased illuminance. In the present embodiment, a contrivance is made to reflect such individual differences in the set value of illuminance during high-illuminance illumination. Specifically, the physiological information after high-illuminance illumination for a certain period of time is sent to the determination unit 16 and compared with the appropriate value of the physiological information, whether the arousal level is appropriate or inappropriate is sent to the illuminance adjustment unit 18. . When the illuminance adjusting means determines that the arousal level is inappropriate, the illuminance level is increased by ΔL during the next high illuminance irradiation, and Lx2 + ΔL is output to the control means as a target value. When the control of the high illuminance illumination is completed, the same procedure is repeated with Lx2 + ΔL as a new Lx2. By doing so, the high illuminance set value Lx2 can be raised to an appropriate level for the individual. In FIG. 17, only the process of increasing Lx2 has been described, but the reverse process can also be realized by the same procedure. When the physiological information is larger than the appropriate value by a predetermined width or more at the same set value Lx2 in several control cycles, the set value is lowered by -ΔL. For the next high illuminance irradiation, irradiation is performed at a reduced illuminance. When this high illuminance irradiation is completed, ΔLx2−ΔL may be set as a new Lx2, and the same procedure may be repeated.

1 is an overall configuration example of an illuminance control system according to an embodiment of the present invention. FIG. 2 is a block diagram of the system of FIG. It is a figure which shows an example of the adjustment system of the illumination intensity adjustment means of the system of FIG. It is explanatory drawing of the structure of an electrocardiogram. It is a perspective view of the use condition of the illumination intensity sensor of the system of FIG. It is the side view and top view of an illumination intensity sensor. It is a figure which shows the illumination change within the vertical viewing angle measured with one of the illumination intensity sensors of FIG. It is a flowchart which shows the flow of the illumination intensity control of the system of FIG. It is a figure explaining the system of the experiment for the effect confirmation of the system of FIG. It is a graph which shows the displacement of LF / HF of a human body when an irradiation experiment is done with the system of FIG. It is a graph which shows the displacement of the heart rate of a human body when performing the irradiation experiment of FIG. It is a graph which shows the displacement of HF of a human body when the irradiation experiment of FIG. 10 is performed. It is the table | surface which shows the value which averaged LF / HF when performing an irradiation experiment on the illumination conditions (Case3) of this invention, normal illumination conditions (Case1), and the conditions (Case2) of the conventional schedule control type circadian illumination. is there. It is the figure which compared HF and LF / HF at the time of sleep on the conditions of Case3 and Case2 as shown in FIG. It is a figure which shows the whole structure of the illumination intensity control system which concerns on the 2nd Embodiment of this invention. FIG. 16 is a block diagram of the system of FIG. It is a flowchart which shows the flow of control of the illumination intensity control system which concerns on the 3rd Embodiment of this invention.

Explanation of symbols

2 ... Illumination means 4 ... Illuminance sensor 5 ... Hood 6 ... Control means 8 ... Biosensor 10 ... Motion detection means 12 ... Analysis means
DESCRIPTION OF SYMBOLS 14 ... Memory | storage means 16 ... Judgment means 18 ... Illuminance adjustment means 20 ... Warning part 22 ... Input part

Claims (5)

Provided with a feedback control system for detecting the illuminance in a specific lighting area and adjusting the lighting output so that the illuminance becomes a predetermined value, and to increase the illuminance in some time of day A lighting control system capable of
A lighting means with adjustable lighting output for illuminating a personal lighting area;
An illuminance sensor for detecting the illuminance in the illumination area;
Control means for controlling the output of the illumination means so that the detected illuminance approaches the target value;
A biological sensor for detecting personal physiological information that changes in accordance with the illuminance in the illumination area;
Storage means capable of recording at least individual physiological information for each individual;
By comparing the physiological information detected by the biometric sensor with the physiological information data at the time of the normal awakening of the individual, the level of the individual's awakening is at least two levels of the normal awakening level and the low awakening level. Determining means for determining in
Illuminance adjusting means for automatically changing the target value of the control means according to the determined arousal level;
Have
In response to the determination by the determination unit, the illuminance adjustment unit is configured to make the target value of the control unit higher than the normal level and return the target value to the normal level after a predetermined length of high illuminance irradiation time has elapsed. A lighting control system for physiological information. Furthermore, it has an action detecting means for detecting an action of an individual in an illumination area that also serves as a work place, and an analyzing means for analyzing physiological information,
The analysis means evaluates the activity level of the individual from the detected action, and forms the value of the physiological information when the activity level is high to be stored in the storage means separately from the physiological information when the activity level is low,
2. The physiological information-corresponding illumination control according to claim 1, wherein the wakefulness level is determined based on the physiological information when the activity level is high as physiological information at the time of normal past awakening of the individual. system. The illuminance adjustment means is replaced with a configuration that automatically changes the target value in accordance with the determination by the determination means.
In response to the above determination, an alerting section that informs of a decrease in arousal level,
An input unit that allows an individual to input an illuminance increase command;
3. The physiological information corresponding illumination control system according to claim 2, wherein the target value of the control means is changed in response to an input of the illuminance increase command. The biometric sensor detects a person's heartbeat as information on an electrocardiogram format together with the time of beat,
The determination means performs a Fourier transform on the heart rate data to extract a high frequency component (HF) and a low frequency component (LF), and the ratio of the high frequency component to the low frequency component (LF / HF) is normally awake. 4. The physiological information-compatible lighting control according to claim 2, wherein the lighting control is designed to determine that the level of low arousal is high when compared to the (LF / HF) data of the individual. system. The illuminance sensor can be attached near the head of an individual,
In its attached state, while orienting the light receiving surface of the illuminance sensor in front of the person's vertical viewing angle,
The physiological information-compatible illumination control system according to any one of claims 2 to 4, further comprising a light shielding hood that blocks light from directions other than the front.

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