KR102770840B1 - Lighting device - Google Patents

Abstract

The present invention provides indoor lighting that, like outdoor sunlight, increases work concentration during the day and reduces sleep disruption at night.
Accordingly, a lighting device according to one aspect of the present invention includes a first LED package having emission peaks in a first wavelength range and a second wavelength range, a second LED package having an emission peak in the first wavelength range, and a control unit that varies the relative intensity of an emission peak existing in the second wavelength range based on the intensity of an emission peak existing in the first wavelength range on a light spectrum.

Description

LIGHTING DEVICE

The present invention relates to a lighting device, and more specifically, to an indoor lighting device that regulates a user's biological rhythm.

Recently, LED lighting has become popular. LED, or light emitting diode, refers to a device that creates injected minority carriers (electrons or holes) using the p-n junction structure of a semiconductor and emits a certain amount of light through their recombination. There are red light emitting diodes using GaAsP, green light emitting diodes using GaP, and blue light emitting diodes using InGaN/AlGaN double hetero structures.

Recent lighting devices combine light-emitting diode chips and phosphor molds to produce white light. For example, a phosphor is placed on top of a blue light-emitting diode chip to obtain white light through the blue emission of the light-emitting diode chip and the yellow-green or yellow emission of the phosphor. That is, white light is produced by combining a blue light-emitting diode chip made of a semiconductor component that emits light with a wavelength of 430 nm to 480 nm and a phosphor that uses blue light as an excitation source to emit yellow-green and yellow light.

However, recently, adverse effects of blue light from white-emitting lighting devices have been reported. Blue light is known to disrupt biological rhythms and destroy sleep cycles. In response, prior art documents disclose human-friendly lighting devices that control the overall color temperature by driving a first light-emitting element with a relatively short emission peak wavelength and a second light-emitting element with a relatively long emission peak wavelength, respectively.

However, the prior art document sets the color temperature of the first light-emitting element very low and controls the light-emitting element in a way that lowers the overall color temperature in a nighttime environment, so although it may be helpful in activating melatonin, it has a problem that the concentration may actually decrease compared to general lighting in a work environment during the day when concentration is required.

Furthermore, in the second light-emitting element of the prior art document or the entire lighting module, the relative intensities of the two emission peaks existing in the blue series are similarly distributed, but there is a problem in that the relative intensity of the emission peak with a relatively longer wavelength is formed to be greater. In this case, the melatonin suppression effect is expressed during the day, but the melatonin activation effect at night is reduced, and there is also a problem in that energy efficiency decreases due to the emission of the relatively shorter wavelength.

In this strict sense, human-friendly lighting should maximize concentration during the day by suppressing melatonin secretion and optimize sleep induction by maximizing melatonin secretion at night, but detailed research is still lacking.

No. 10-2020-0113133 (October 6, 2020), Title of the Invention: White Light EMITTING MODULE

The present invention is intended to solve the problems of the above-mentioned prior art, and an object of the present invention is to provide indoor lighting that, like outdoor sunlight, increases work concentration during the day and reduces sleep-disrupting effects at night.

A lighting device according to one aspect of the present invention includes a first LED package having emission peaks in a first wavelength range and a second wavelength range, a second LED package having an emission peak in the first wavelength range, and a control unit that varies the relative intensity of an emission peak existing in the second wavelength range based on the intensity of an emission peak existing in the first wavelength range on a light spectrum.

At this time, the first wavelength range may be formed from 400 to 470 nm, and the second wavelength range may be formed from 470 nm to 490 nm.

Additionally, the relative intensity of a peak existing in the second wavelength region in the second LED package on the optical spectrum may be formed to be smaller than the relative intensity of a luminescence peak existing in the first wavelength region.

Additionally, the second LED package may have a color temperature of 1800 to 6500K.

Additionally, the relative intensity of the emission peak existing in the second wavelength range based on the emission peak intensity of the first wavelength range existing in the first LED package may be 1.2 to 2.0.

Additionally, the first LED package may have a color temperature of 4000 to 6500K.

In addition, the control unit can vary the color temperature of the entire indoor lighting device by varying the relative intensity of the emission peak of the second wavelength range based on the emission peak intensity of the first wavelength range.

In addition, the first LED package may have one peak wavelength in each of the first wavelength region and the second wavelength region, and the second LED package may have a peak wavelength only in the first wavelength region.

In addition, the indoor lighting device further includes an input unit for inputting a natural light mode or a special mode, and the control unit can vary the relative intensity of the emission peak of the first wavelength and the emission peak of the second wavelength according to the input value.

In addition, when the natural light mode is input, the control unit can divide the time from sunrise to sunset into a set number of sections and set the color temperature change amount in each section differently.

In addition, the above-described set number of sections may be formed into three sections, and the amount of color temperature change in the first section among the three sections may be formed to be greater than the amount of color temperature change in the second section, and the amount of color temperature change in the third section may be formed to be greater than the amount of color temperature change in the first section.

In addition, the indoor lighting device further includes a communication unit or a storage unit, and the communication unit or the storage unit can receive or store the sunrise and sunset times.

In addition, the first LED package and the second LED package are formed in multiples, and the control unit can determine the number of driving or applied current of the first LED package and the second LED package.

Meanwhile, a lighting device according to another aspect of the present invention includes a first LED package having a wavelength peak of a first wavelength and a wavelength peak of a second wavelength, a second LED package having a wavelength peak of the first wavelength and not having a wavelength peak of the second wavelength, and a control unit that adjusts an overall color temperature by varying an emission peak intensity of the second wavelength based on an emission peak intensity of the first wavelength on a light spectrum.

The lighting device according to the present invention can maximize the change in the M/P ratio by adjusting the relative intensity of the first wavelength region and the second wavelength region, thereby increasing work concentration during the day and reducing the sleep-disrupting effect at night.

Figure 1 is a configuration diagram of a lighting device according to one embodiment of the present invention.
FIG. 2a and FIG. 2b are cross-sectional views of the first LED package and the second LED package constituting the light source unit in FIG. 1, respectively.
FIG. 3 is a drawing illustrating the optical spectrum of the first LED package of FIG. 2.
FIG. 4 is a drawing illustrating the optical spectrum of the second LED package of FIG. 2.
FIGS. 5A to 5D are drawings showing that the light spectrum changes over time when a lighting device according to one embodiment of the present invention is driven in a natural light mode.
FIGS. 6A to 6D are diagrams illustrating light spectra when a lighting device according to one embodiment of the present invention is set to a daily mode, a rest mode, a concentration mode, and a night activity mode, respectively.
FIGS. 7A and 7B are diagrams illustrating changes in the light spectrum when a lighting device according to one embodiment of the present invention is set to a weather mode.
FIG. 8 is a diagram illustrating a change in the light spectrum when a lighting device according to one embodiment of the present invention is set to a sleep induction mode.

Hereinafter, with reference to the attached drawings, embodiments of the present invention will be described in detail so that those skilled in the art can easily implement them. The present invention can have various modifications and various embodiments, and specific embodiments will be described in detail by exemplifying them in the drawings. However, this is not intended to limit the present invention to specific embodiments, and it should be understood that it includes all modifications, equivalents, and substitutes included in the spirit and technical scope of the present invention.

Terms including ordinal numbers, such as first, second, etc., may be used to describe various components, but the components are not limited by the terms. The terms are used only to distinguish one component from another.

For example, without departing from the scope of the present invention, the first component could be referred to as the second component, and similarly, the second component could also be referred to as the first component. The term and/or includes any combination of a plurality of related described items or any item among a plurality of related described items.

Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms defined in commonly used dictionaries, such as those defined in common dictionaries, should be interpreted as having a meaning consistent with the meaning they have in the context of the relevant art, and will not be interpreted in an idealized or overly formal sense unless expressly defined in this application.

Hereinafter, a lighting device according to an embodiment of the present invention will be described. FIG. 1 is a configuration diagram of a lighting device according to an embodiment of the present invention, FIGS. 2a and 2b are cross-sectional views of a first LED package and a second LED package constituting a light source unit in FIG. 1, respectively, FIG. 3 is a diagram illustrating an optical spectrum of the first LED package of FIG. 2, and FIG. 4 is a diagram illustrating an optical spectrum of the second LED package of FIG. 2.

Referring to the drawings, in one embodiment of the present invention, a lighting device (1000) is largely composed of a light source unit (100) and a control unit (200) that controls the operation of the light source unit (100), and may further include a storage unit (300), an input unit (400), and a communication unit (500) as illustrated in FIG. 1.

First, the light source unit (100) according to the present embodiment is composed of at least one first LED package (110) and at least one second LED package (120). At this time, the first LED package (110) and the second LED package (120) are formed by including a substrate (111, 121), an LED bare chip (113, 123), and a fluorescent substance (114, 124), and may further include a reflector (112, 122) as illustrated. At this time, the first LED package (110) and the second LED package (120) may have the substrate (111, 121) and the reflector (112, 122) formed in the same manner.

The substrate (111, 121) may be formed as a straight, circular or polygonal plate, and in this embodiment, the substrate (111, 121) may be electrically connected to the LED bare chip (113, 123) through wiring or through a soldering portion (not shown) and may not have a separate bonding wire. The soldering portion may be formed using a surface mount technology (SMT).

However, in this embodiment, the first LED package (110) suppresses melatonin and thus serves to provide vitality to the user, and therefore, in addition to the bare chip 1a (113a) for basically emitting white light, it is characterized by further including the bare chip 1b (113b) for emitting light of another wavelength range.

Here, bare chip 1a (113a) emits light of 400 to 470 nm (referred to as “first wavelength range”, the same applies hereinafter), and bare chip 1b (113b) emits light of 470 to 490 nm (referred to as “second wavelength range”, the same applies hereinafter). Furthermore, referring to Fig. 3, the intensity ratio of the second wavelength range emission peak based on the intensity of the first wavelength range emission peak is formed as 1.2 to 2.0.

At this time, if the intensity ratio of the above-mentioned luminescence peak is less than 1.2, the light in the first wavelength range is widely recognized, so that a sufficient melatonin suppression effect is not generated. If it exceeds 2.0, the melatonin suppression effect is expressed, but the melatonin suppression effect is saturated due to the photofatigue phenomenon.

In more detail, in the present embodiment, even if the light emitted by the second LED package (120) described below is mixed with the light emitted by the first LED package (110) to produce the target color temperature, the melatonin suppression effect may be reduced as the wavelength peak in the first wavelength range of the first LED package (110) remains and is irradiated to the user. Therefore, as described above, it is highly desirable to set the ratio of the peak intensity in the second wavelength range to the peak intensity in the first wavelength range, which is the wavelength range of basic white light.

At this time, as shown in FIG. 2a, the first LED package (110) includes a phosphor (114). As shown, the phosphor (114) excites light emitted from the LED bare chip (113) to emit white light. The phosphor (114) can be manufactured mainly using a phosphor (Y) whose wavelength is yellow when excited, as a main component, and a red (R) series or green (G) series phosphor (114a, 114b) can be used. Meanwhile, the phosphor (114) is formed to be distributed within the base resin matrix so as to cover the bare chip (113), and it is preferable that the final emitted light has a color temperature of 4000 to 6500K for the melatonin suppression effect of the first LED package (110).

Meanwhile, the second LED package (120) plays a role in activating melatonin and helping with rest and deep sleep. As shown in Fig. 2b, the second LED package (120) is similar to the first LED package (110) and includes a substrate (121), bare chip 2 (123), and a fluorescent substance (124), and may further include a reflector (112, 122).

Here, bare chip 2 (123) emits light having an emission peak in the first wavelength range (400 to 470 nm). In addition, as shown in the drawing, in order to secure current control and color uniformity by the aforementioned control unit, bare chip 2 (123) may be formed of two that emit the same light. In addition, since the second LED package (120) is involved in the activation of melatonin, when further including a bare chip having an emission peak in the second wavelength range, it is preferable that the relative intensity of the peak existing in the second wavelength range on the light spectrum be formed to be smaller than the relative intensity of the emission peak existing in the first wavelength range. Furthermore, for the activation of melatonin, it is preferable that the phosphor (124) in the second LED package (120) be set to emit final light having a lower color temperature than the phosphor (114) in the first LED package (110). Accordingly, it is preferable that the color temperature of the final light emitted from the second LED package (120) be in the range of 1800 to 6500K.

Meanwhile, the control unit (200) controls the first LED package (110) and the second LED package (120) respectively to control the color temperature of the entire lighting device. However, the lighting device according to one embodiment of the present invention is characterized in that the color temperature of the entire lighting device is changed by varying the relative intensity of the emission peak of the second wavelength range based on the emission peak intensity of the first wavelength range. When the driving current ratio of the first LED package (110) and the second LED package (120) is adjusted according to the relative intensity of the emission peak, a higher level of M/P ratio change is possible, thereby inducing a melatonin suppression or activation effect similar to natural light.

Hereinafter, a lighting device according to one embodiment of the present invention will be described in more detail. The lighting device according to the present embodiment has a natural light mode or a selection mode depending on the input of the input unit (400).

The case of natural light mode will be described with reference to FIGS. 5A to 5D. FIGS. 5A to 5D are drawings showing that the light spectrum changes over time when a lighting device according to one embodiment of the present invention is driven in natural light mode.

Natural light mode performs the function of maximizing the melatonin effect by designating a specific time zone, and changes the color temperature of the entire lighting device to 3000 (or 4000) to 6500K according to the scheduled time zone.

In natural light mode, the control unit (200) divides the time from sunrise to sunset into a set number of sections and sets the color temperature increase/decrease amount in each section differently. It is important to continuously change the color temperature from waking up to going to bed to activate melatonin, but the melatonin activation effect is greater when the rate of change in color temperature changes according to the section.

At this time, the above-mentioned set number of sections is formed into three sections from the time after waking up to going to bed, and it is most preferable that the color temperature change amount in the first section (e.g., 7:00 to 12:00) of the three sections is formed to be greater than the color temperature change amount in the second section (e.g., 12:00 to 18:00), and the color temperature change amount in the third section (e.g., 18:00 to 24:00) is formed to be greater than the color temperature change amount in the first section.

In the third section, the amount of change in color temperature should be the greatest before going to bed to facilitate the synthesis of melatonin, and the amount of change in the second section should be the smallest so that the decrease in color temperature in the third section can be smoothly detected by the human body. In addition, it is desirable that the amount of change in the first section be less than that in the third section to facilitate smooth daytime activities.

Detailed implementations of these natural light modes are described in Table 1 below.

hour 7 o'clock 12 o'clock 6 o'clock 24 hours Color temperature 6500K 6000K 5700K 4000K Package Drive
ratio Package 1 100% 90% 70% 0% Package 2 0% 10% 30% 100% Product brightness 100% 100% 100% 100%

Referring to Fig. 5a, which is a luminous spectrum at 7 o'clock set as the wake-up time, the peak intensity of the second wavelength region is set to 1.2 to 2.0 compared to the peak intensity of the first wavelength region, and the color temperature is set to 6500 K. This results in a strong suppression effect on melatonin secretion.

Also, referring to Fig. 5b, which is the emission spectrum at 12:00 noon, which is lunch time, the peak intensity of the second wavelength region is set to 1.2 to 2.0 compared to the peak intensity of the first wavelength region, and the color temperature is set to 6000 K. Accordingly, a strong suppression effect on melatonin secretion is continuously elicited, while melatonin suppression begins to be alleviated.

Also, referring to Fig. 5c, which is the emission spectrum at 6 p.m. in the evening, the peak intensity of the second wavelength region is set to 0.8 to 1.6 compared to the peak intensity of the first wavelength region, and the color temperature is set to 5700 K. In this case, melatonin activation begins in earnest while functioning as active lighting necessary for work depending on the residual white light.

Afterwards, referring to Fig. 5d, which is the emission spectrum at 24:00 PM, which is the bedtime, the peak intensity of the second wavelength region is set to 0.3 or less compared to the peak intensity of the first wavelength region, and the color temperature is set to 4000 K. In this case, since no peak is generated in the second wavelength region, a sleeping environment is created.

Meanwhile, in the case of the selection mode, the daily mode, rest mode, concentration mode, night activity mode, and sleep induction mode can be input, and the control unit varies the relative intensity of the emission peak of the first wavelength and the emission peak of the second wavelength according to the input.

FIGS. 6A to 6D are diagrams illustrating light spectra when a lighting device according to an embodiment of the present invention is set to a daily mode, a rest mode, a concentration mode, and a night activity mode, respectively, and FIGS. 7A to 7B are diagrams illustrating changes in a light spectrum when a lighting device according to an embodiment of the present invention is set to a wake-up mode, and FIG. 8 is a diagram illustrating changes in a light spectrum when a lighting device according to an embodiment of the present invention is set to a sleep induction mode.

Detailed implementations of these selection modes are described in [Table 2] and [Table 3] below.

Drive mode Daily mode Rest mode Focus mode Night activity mode Color temperature 5700K 4000K 6500K 5000K Package
Drive
ratio Package 1 70% 0% 100% 50% Package 2 30% 100% 0% 50% Product brightness 100% 70~80% 100% 100%

Drive mode Weather Mode Sleep induction mode Color temperature 5000K → 6500K 4000K Package Drive
ratio Package 1 70% → 100% 0% Package 2 30% → 0% 100% Product brightness 10% → 100% (30 minutes) 70~80% → Off (takes 30 minutes)

In the weather mode, as shown in Fig. 7a, light of 5000 K with a peak intensity of the second wavelength region of 0.6 to 1.2 compared to the peak intensity of the first wavelength region is emitted, and after a set time, light of 6500 K with a peak intensity of the second wavelength region of 1.2 to 2.0 compared to the peak intensity of the first wavelength region is emitted, thereby maximizing the awakening effect of melatonin suppression.

In addition, in sleep induction mode, as shown in Fig. 8, light of 4000K with a peak intensity of the second wavelength range of 0.3 or less compared to the peak intensity of the first wavelength range is emitted and turned off after a set time, thereby maximizing the melatonin activation effect.

As described above, the present specification and drawings have disclosed preferred embodiments of the present invention, and although specific terms have been used, they have been used only in a general sense to easily explain the technical contents of the present invention and to help understand the invention, and are not intended to limit the scope of the present invention. It will be apparent to those skilled in the art that other modified examples based on the technical idea of the present invention can be implemented in addition to the embodiments disclosed herein.

1000: Lighting Device
100: Light source
110: 1st LED package
120: 2nd LED package
111, 121: Substrate
112: 122: Reflector
113: Bare Chip 1
113a: Bare Chip 1a, 113b: Bare Chip 1b
123: Bare Chip 2
114, 124: Phosphor
200: Control Unit
300: Storage
400: Input section
500: Communications Department

Claims (14)

In lighting devices,
A first LED package having emission peaks in the first wavelength region and the second wavelength region;
A second LED package having an emission peak in the first wavelength region; and
A control unit that varies the intensity of an emission peak existing in the second wavelength range based on the intensity of an emission peak existing in the first wavelength range on the optical spectrum;
Including,
The above control unit divides the time from sunrise to sunset into a set number of sections and sets the amount of color temperature change in each section differently, or
A lighting device characterized in that the control unit varies the relative intensity of the emission peak of the first wavelength and the emission peak of the second wavelength according to the input value.
delete In the first paragraph,
A lighting device characterized in that the relative intensity of a peak existing in the second wavelength range in the second LED package on the light spectrum is formed to be smaller than the relative intensity of a luminescence peak existing in the first wavelength range.
delete In the first paragraph,
A lighting device characterized in that the relative intensity of the emission peak existing in the second wavelength range is 1.2 to 2.0 based on the emission peak intensity of the first wavelength range existing in the first LED package.
delete In the third paragraph,
A lighting device characterized in that the control unit can vary the color temperature of the entire lighting device by varying the relative intensity of the emission peak of the second wavelength range based on the emission peak intensity of the first wavelength range.
delete delete delete In the first paragraph,
A lighting device characterized in that the above-mentioned set number of sections is formed into three sections, the amount of color temperature change in the first section among the three sections is formed to be greater than the amount of color temperature change in the second section, and the amount of color temperature change in the third section is formed to be greater than the amount of color temperature change in the first section.
delete In the first paragraph,
A lighting device characterized in that the first LED package and the second LED package are formed in multiples, and the control unit determines the number of driving or applied current of the first LED package and the second LED package.
delete