A smart air purification system and method

Abstract

This invention discloses an intelligent air purification system, comprising: a first purification unit for purifying air entering the air purifier; a detection unit for detecting ambient air quality indicators; a sensing unit for detecting the presence of a human body in the space where the air purifier is located; and a second purification unit for purifying the waste generated by the first purification unit. The intelligent air purification system disclosed in this invention can further reduce the purifier's operating energy consumption and noise, improve purification efficiency, and enhance human comfort.

Description

Technical Field

[0001] This invention relates to an intelligent air purification method and system, belonging to the field of air purification technology. Background Technology

[0002] Traditional air purification systems mostly use a single purification unit and a single purification strategy. In actual use, they can only adjust their operation based on the indoor air conditions and cannot be intelligently controlled in conjunction with other environmental factors. This results in the purifier's energy consumption, noise, and even human sensory experience not reaching their optimal levels.

[0003] For the reasons mentioned above, the inventors have conducted in-depth research on existing intelligent air purification methods in order to further reduce the operating energy consumption and noise of purifiers, improve purification effects, and enhance comfort. Summary of the Invention

[0004] To overcome the above problems, the inventors conducted in-depth research and designed an intelligent air purification system, comprising:

[0005] The first purification unit is used to purify the air entering the air purifier;

[0006] The detection unit is used to detect ambient air quality indicators.

[0007] The sensing unit is used to detect whether there are human beings in the space where the air purifier is located;

[0008] The second purification unit is used to purify the waste generated by the first purification unit.

[0009] In a preferred embodiment, an intelligent control unit is also included for remote control of the purifier.

[0010] In a preferred embodiment, the first purification unit is one or more of the following: a HEPA filter, an activated carbon filter, an electrostatic dust collection module, a plasma module, a negative ion module, a photocatalyst module, and a nano-photocatalytic module.

[0011] In a preferred embodiment, the sensing unit is one or more of the following: microwave radar, light radar, ultrasonic sensor, infrared ranging sensor, carbon dioxide sensor, touch sensor, and infrared photoelectric sensor.

[0012] In a preferred embodiment, the second purification unit is one or more of the following: a high-voltage electrostatic module, an ultraviolet light module, an ozone generating module, and a chlorine dioxide generating module.

[0013] This invention also provides an intelligent air purification method, which utilizes the aforementioned intelligent air purification system.

[0014] Set the startup threshold B = {b} i |i=[1,n]} is used to represent the start-up indicators of the air purifier, where i represents different test items, n represents the total number of test items, and b i This represents the activation threshold for the i-th detection item;

[0015] The ambient air quality index A = {a} is continuously monitored by the detection unit. i |i=[1,n]}, where a i This represents the detection value of the i-th detection item:

[0016] Scenario 1: When any one of the air quality indicators, a, is detected. i Below the corresponding startup threshold b i At this time, the air purifier is in standby mode;

[0017] Scenario 2: When any one of the air quality indicators a is detected i Higher than the corresponding startup threshold b i Turn on the air purifier when needed.

[0018] In a preferred embodiment, the upshift threshold C = {c i,j |i=[1,n],j=[1,m]} is used to represent the power level indicators of an air purifier, where j represents the different power levels of the air purifier, c i,j This represents the detection value of the i-th detection item in the j-th power level;

[0019] Set the standby threshold D = {d} i |i=[1,n]} is used to represent the standby index of the air purifier, where d i Indicates the standby value of the i-th detection item:

[0020] In scenario 2, after the air purifier is turned on, the following steps are included:

[0021] Use the lowest power setting as the initial operating setting;

[0022] After each X1 running time, the ambient air quality index A = {a} is measured. i |i=[1,n]}, until the air purifier enters standby mode:

[0023] Scenario 21: When any one of the air quality indicators a is detected i Below the corresponding standby value d i When this happens, the air purifier enters standby mode;

[0024] Scenario 22: When any one of the air quality indicators a is detected i The shift threshold c is lower than the shift threshold corresponding to the next lower power level. i,j-1When the air purifier is running at a lower power level, it will maintain the lowest power level if the current power level is already the lowest.

[0025] Scenario 23: When any one of the air quality indicators a is detected i Below the upshift threshold c corresponding to the current gear i,j And it is higher than the upshift threshold c corresponding to the next lower power level of the current gear. i,j-1 At this time, the air purifier continues to operate at its current power setting;

[0026] Scenario 24: When any one of the air quality indicators a is detected i The shift threshold c is higher than the current gear's corresponding shift threshold. i,j When the air purifier is in use, it will operate at a higher power level. If the current power level is already the highest level, it will maintain the highest power level.

[0027] In a preferred embodiment, the current daytime and nighttime states are obtained. When the air purifier is in nighttime state, in case 21, it no longer enters standby mode and maintains operation at the lowest power level.

[0028] In a preferred embodiment, the ambient light intensity is obtained through a sensing unit, and the day and night states are obtained based on the changes in light intensity.

[0029] In a preferred embodiment, the presence of a human body in the space where the air purifier is located is detected by a sensing unit. When no human body is present, the second purification unit is activated.

[0030] The beneficial effects of this invention include:

[0031] (1) It can automatically control the operating power of the purifier according to the air environment and the state of the human body, thereby reducing energy consumption and ensuring a low-noise experience for users;

[0032] (2) It has a good purification effect and will not produce odors after long-term use. Attached Figure Description

[0033] Figure 1 A schematic cross-sectional structure diagram of an intelligent air purification system according to a preferred embodiment of the present invention is shown.

[0034] Figure 2 An exploded view of the second purification unit and the overall system of an intelligent air purification system according to a preferred embodiment of the present invention is shown.

[0035] Figure 3 A diagram showing the location of the high-voltage electrostatic module in an intelligent air purification system according to a preferred embodiment of the present invention is provided.

[0036] Explanation of icon numbers:

[0037] 1-First purification unit;

[0038] 4-Second purification unit;

[0039] 6-Air duct;

[0040] 11-Activated carbon filter screen;

[0041] 12-HEPA filter;

[0042] 13-Gas sterilization channel;

[0043] 41-Ozone Generating Module;

[0044] 42-Ultraviolet light module;

[0045] 43-High voltage electrostatic module;

[0046] 61-Wind fan. Detailed Implementation

[0047] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Through these descriptions, the features and advantages of the present invention will become clearer and more apparent.

[0048] The term “exemplary” as used herein means “serving as an example, embodiment, or illustration.” Any embodiment illustrated herein as “exemplary” is not necessarily to be construed as superior to or better than other embodiments. Although various aspects of embodiments are shown in the accompanying drawings, the drawings are not necessarily drawn to scale unless specifically indicated otherwise.

[0049] An intelligent air purification system according to the present invention includes:

[0050] The first purification unit 1 is used to purify the air entering the air purifier;

[0051] The detection unit is used to detect ambient air quality indicators.

[0052] The sensing unit is used to detect whether there are human beings in the space where the air purifier is located;

[0053] The second purification unit 4 is used to purify the waste generated by the first purification unit.

[0054] In a preferred embodiment, the air purifier further includes an intelligent control unit for remote control of the purifier.

[0055] According to the present invention, the first purification unit 1 is one or more of the following: HEPA filter, activated carbon filter, electrostatic dust collection module, plasma module, negative ion module, photocatalyst module, and nano-photocatalytic module;

[0056] The detection unit is one or more of the following: wind pressure and flow sensor, air quality sensor, laser dust sensor, formaldehyde sensor, temperature and humidity sensor, VOC sensor, carbon dioxide sensor, and ozone sensor.

[0057] The sensing unit is one or more of the following: microwave radar, light radar, ultrasonic sensor, infrared ranging sensor, carbon dioxide sensor, touch sensor, and infrared photoelectric sensor.

[0058] The second purification unit 4 is one or more of the following: ozone generation module 41, chlorine dioxide generation module, ultraviolet light module 42, and high voltage electrostatic module 43.

[0059] In this invention, the specific models of the modules involved in the first purification unit and the second purification unit are not limited. Those skilled in the art can freely choose according to actual needs. For example, the electrostatic dust collection module is Hengjing Technology hj-dlz-230, the plasma module is Zhoudu ZD-120-62-25, the negative ion module is TrumpXP's TFB-Y32, the photocatalyst module is a tank containing photocatalyst, the nano-photocatalysis module is a nano-photocatalyst mesh, the ozone generation module is Baiyuekang FQA-063T, the chlorine dioxide generation module is a chlorine dioxide generator, and the high-voltage electrostatic module is Tianwang TW-DC-DP.

[0060] After an air purifier has been working for a long time, the first purification unit will intercept and adsorb various particulate matter or microorganisms. When the air purifier is turned off, there will be secondary metabolism of microorganisms or odors due to the metabolism of microorganisms carried by the particulate matter itself. In this invention, the problem is solved by setting a second purification unit.

[0061] The intelligent control unit can be any type of internet-based control chip, including Wi-Fi, Bluetooth, infrared, LoRa, and Zigbee communication chips.

[0062] Furthermore, the intelligent air purification system also has an air duct 6, in which a fan 61 is installed to facilitate the exchange of air between the air purification system and the outside air.

[0063] According to a preferred embodiment of the present invention, such as Figure 1 As shown, the air duct 6 is vertically arranged, and the fan 61 is arranged in the air duct 6, preferably at the top of the air duct 6. The first purification unit 1 is arranged on the side of the air duct 6. Under the action of the fan 61, the outside air enters the air duct 6 through the first purification unit 1 and is discharged from the top of the air duct 6.

[0064] In a preferred embodiment, the second purification unit 4 includes an ozone generating module 41 and / or a chlorine dioxide generating module, and the first purification unit 1 includes an activated carbon filter 11 and a HEPA filter 12. The activated carbon filter 11 is disposed in the inner layer of the first purification unit 1, and the HEPA filter 12 is disposed in the outer layer of the first purification unit 1. A gas sterilization channel 13 is provided between the activated carbon filter 11 and the HEPA filter 12. The ozone generating module 41 and / or the chlorine dioxide generating module are disposed at the end of the first purification unit 1, so that the generated ozone or chlorine dioxide can enter the gas sterilization channel 13.

[0065] When the ozone generating module 41 and / or the chlorine dioxide generating module are working, the generated ozone or chlorine dioxide enters the gas sterilization channel 13 and comes into contact with the HEPA filter 12, killing the microorganisms attached to the HEPA filter 12. Furthermore, at this time, the fan 61 operates at a preset speed, which creates negative pressure in the air duct, and the air flows from the HEPA filter 12 to the activated carbon filter 11, thereby driving the ozone or chlorine dioxide to the activated carbon filter. The activated carbon filter adsorbs the ozone or chlorine dioxide, thereby preventing the ozone or chlorine dioxide from escaping from the air purification system.

[0066] Furthermore, when other modules are also provided in the first purification unit 1, the other modules are set in the gas sterilization channel 13 so that ozone or chlorine dioxide can diffuse into the other modules to achieve sterilization of all modules in the first purification unit 1.

[0067] The other modules refer to one or more of the following: electrostatic dust collection module, plasma module, negative ion module, photocatalyst module, and nano-photocatalysis module.

[0068] More preferably, such as Figure 2 As shown, the ozone generating module 41 or the chlorine dioxide generating module is located at the lower end of the first purification unit 1. Since the air outlet of the air duct is above the air purifier, the above arrangement allows the ozone or chlorine dioxide generated by the ozone generating module or the chlorine dioxide generating module to diffuse rapidly upward in the gas sterilization channel 13 under the influence of the outside air.

[0069] In a more preferred embodiment, the first purification unit 1 is barrel-shaped, the activated carbon filter 11 and the HEPA filter 12 are both annular, and the ozone generating module 41 or the chlorine dioxide generating module is located at the bottom of the barrel and connected to the gas sterilization channel 13 through a pipe.

[0070] In a preferred embodiment, the ultraviolet light module 42 is disposed at the bottom of the first purification unit 1, so that the generated ultraviolet light irradiates the air duct 6, which sterilizes and disinfects the air duct while preventing ultraviolet light from leaking out of the purification system and reducing damage to the environment.

[0071] In a preferred embodiment, such as Figure 3 As shown, the high-voltage electrostatic module 43 is installed in the air duct 6, preferably at the upper part of the air duct 6 near the lower part of the fan 61. The discharge electrode and the collection electrode of the high-voltage electrostatic module 43 are located on both sides of the air duct, so that when the air passes through the high-voltage electrostatic module 43, the high-voltage electric field decomposes the air into positive and negative ions to form an ionization layer, thereby achieving the dust removal effect on the fan and removing the waste remaining on the fan after purification by the first purification unit.

[0072] In a preferred embodiment, there are two sets of detection units, which are respectively installed on the side wall of the air purification system and at the air outlet of the air purification system. The detection unit installed on the side wall of the air purification system is used to detect the ambient air index of the environment in which the air purification system is located, i.e., the indoor air index, while the detection unit installed at the air outlet of the air purification system is used to detect the purified air index after purification.

[0073] The present invention also provides an intelligent air purification method, which uses the above-mentioned intelligent air purification system and includes the following steps:

[0074] Set the startup threshold B = {b} i |i=[1,n]} is used to represent the start-up indicators of the air purifier, where i represents different test items, n represents the total number of test items, and b i This represents the activation threshold for the i-th detection item;

[0075] The ambient air quality index A = {a} is continuously monitored by the detection unit. i |i=[1,n]}, where a i This represents the detection value of the i-th detection item:

[0076] Scenario 1: When any one of the air quality indicators, a, is detected. i Below the corresponding startup threshold b i At this time, the air purifier is in standby mode;

[0077] Scenario 2: When any one of the air quality indicators a is detected i Higher than the corresponding startup threshold b i Turn on the air purifier when needed.

[0078] In this invention, the specific value of the activation threshold is not particularly limited, and those skilled in the art can set it freely as needed. Preferably, it is set according to the value specified in the Chinese standard document "Indoor Air Quality Standard".

[0079] Preferably, during the detection of ambient air indicators by the detection unit, the average value over several consecutive seconds is used as the detection value to reduce the impact of detection fluctuations. More preferably, the several seconds is 1-30 seconds.

[0080] In a preferred embodiment, the upshift threshold C = {c i,j |i=[1,n],j=[1,m]} is used to represent the power level indicators of an air purifier, where j represents the different power levels of the air purifier, c i,j This represents the detection value of the i-th detection item in the j-th power level;

[0081] Set the standby threshold D = {d} i |i=[1,n]} is used to represent the standby index of the air purifier, where d i Indicates the standby value of the i-th detection item:

[0082] In scenario 2, after the air purifier is turned on, the following steps are included:

[0083] Use the lowest power setting as the initial operating setting;

[0084] After each X1 running time, the ambient air quality index A = {a} is measured. i |i=[1,n]}, until the air purifier enters standby mode:

[0085] Scenario 21: When any one of the air quality indicators a is detected i Below the corresponding standby value d i When this happens, the air purifier enters standby mode;

[0086] Scenario 22: When any one of the air quality indicators a is detected i The shift threshold c is lower than the shift threshold corresponding to the next lower power level. i,j-1 When the air purifier is running at a lower power level, it will maintain the lowest power level if the current power level is already the lowest.

[0087] Scenario 23: When any one of the air quality indicators a is detected i Below the upshift threshold c corresponding to the current gear i,j And it is higher than the upshift threshold c corresponding to the next lower power level of the current gear. i,j-1 At this time, the air purifier continues to operate at its current power setting;

[0088] Scenario 24: When any one of the air quality indicators a is detectedi The shift threshold c is higher than the current gear's corresponding shift threshold. i,j When the air purifier is in use, it will operate at a higher power level. If the current power level is already the highest level, it will maintain the highest power level.

[0089] In this invention, the air purifier automatically adjusts its speed based on detected air quality indicators to achieve rapid purification.

[0090] In a preferred embodiment, the current daytime and nighttime states are obtained. When the air purifier is in nighttime state, in case 21, it no longer enters standby mode and maintains operation at the lowest power level.

[0091] More preferably, the ambient light intensity is obtained through the sensing unit, and the white and night states are obtained based on the changes in light intensity. Specifically, the change curve is obtained based on the changes in light intensity, and the white and night states can be obtained based on the change curve. This process is based on the application of curvature change, and the specific method is not described in detail in this invention.

[0092] According to the present invention, the presence of a human body in the space where the air purifier is located is obtained by a sensing unit, and the second purification unit is activated when no human body is present.

[0093] In a preferred embodiment, when the sensing unit detects that there are no human beings in the space where the air purifier is located, and the comprehensive air quality index at the air purifier outlet is lower than the first threshold, the second purification unit is activated.

[0094] The comprehensive air quality index is a weighted average of multiple air purification indicators, expressed as:

[0095]

[0096] Where E represents the comprehensive air quality index, a i ξ represents the detection value of the i-th detection item in the detection unit. i This represents the weight coefficient corresponding to the i-th detection item.

[0097] In this invention, for ξ i The specific setting of the first threshold is not particularly limited; those skilled in the art can set it based on experience.

[0098] In a preferred embodiment, when the second purification unit is turned on, the air purification system is in standby mode, the fan is not started, or the fan only operates at a preset speed that prevents ozone or chlorine dioxide from escaping from the air purification system. That is, the first purification unit is not working at this time, thereby thoroughly sterilizing and disinfecting the first purification unit.

[0099] In a preferred embodiment, when the sensing unit detects that a human body is present in the space where the air purification system is located, it also obtains the distance between the human body and the air purification system.

[0100] Furthermore, a noise power threshold is also provided to characterize the relationship between the power corresponding to acceptable noise and distance. That is, at a certain distance, the air purification system operates at the power of this noise power threshold, and the noise generated is the maximum noise acceptable to the human body. The noise power threshold is preferably stored in the air purification system in tabular form. Furthermore, its specific value is not limited in this invention, and those skilled in the art can set it based on experience.

[0101] When indoor air needs to be purified, the power is adjusted according to the distance between the human body and the air purification system, so that the power is less than or equal to the noise power threshold corresponding to that distance, and the noise generated by the air purification system is within the acceptable range for the human body.

[0102] In a preferred embodiment, atmospheric data of the area where the air purification system is located is also acquired. When the air quality index in the atmospheric data is higher than the activation threshold, the air purification system operates at its lowest setting. In another preferred embodiment, when the presence of a human being is detected in the space where the air purifier is located via the sensing unit, the indoor air quality index is detected. When the air quality index is higher than a second threshold, the power level of the air purifier is no longer limited by the noise power threshold, but it operates directly at the maximum setting until the air quality index falls below the second threshold. Then, the power of the air purifier is readjusted based on the noise power threshold.

[0103] The second threshold is an index value characterizing poor indoor air quality. That is, when the indoor air quality is poor, air purification is prioritized, regardless of noise impact, until the air quality improves to good. In this invention, the specific value of the second threshold can be freely set by those skilled in the art.

[0104] Preferably, a third threshold is also provided to characterize indoor air quality. When the sensing unit detects the presence of a human in the space where the air purifier is located, the comprehensive indoor air index is detected. When the comprehensive air index is lower than the third threshold, the air purifier continues to operate at the lowest setting to maintain indoor air quality until it is detected that there are no more human in the space where the air purifier is located, at which point the air purifier enters standby mode.

[0105] In a preferred embodiment, the working status of the air purifier is remotely controlled by an intelligent control unit.

[0106] In a preferred embodiment, a gas sterilization channel is provided between the activated carbon filter and the HEPA filter of the first purification unit to introduce ozone or chlorine dioxide generated by the ozone generation module and / or the chlorine dioxide generation module, thereby achieving sterilization of the first purification unit. More preferably, a negative pressure is generated by a fan to allow ozone or chlorine dioxide to flow to the activated carbon filter, thereby causing the activated carbon filter to adsorb the ozone or chlorine dioxide flow and preventing ozone or chlorine dioxide from escaping from the air purification system.

[0107] In a preferred embodiment, a high-voltage electrostatic module is installed in the air duct, which creates an ionization layer in the air passing through the high-voltage electrostatic module to remove dust from the fan.

[0108] In the description of this invention, it should be noted that the terms "upper," "lower," "inner," "outer," "front," and "rear," etc., indicate the orientation or positional relationship based on the orientation or positional relationship in the working state of this invention, and are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention. Furthermore, the terms "first," "second," "third," and "fourth" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0109] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0110] The present invention has been described above with reference to preferred embodiments; however, these embodiments are merely exemplary and illustrative. Various substitutions and modifications can be made to the present invention based on these embodiments, all of which fall within the scope of protection of the present invention.

Claims

1. A method of intelligent air purification, using an intelligent air purification system, characterized in that, The intelligent air purification system includes: The first purification unit is used to purify the air entering the air purifier; The detection unit is used to detect ambient air quality indicators. The sensing unit is used to detect whether there are human beings in the space where the air purifier is located; The second purification unit is used to purify the waste generated by the first purification unit. The second purification unit includes an ozone generating module or a chlorine dioxide generating module. The first purification unit includes an activated carbon filter and a HEPA filter. The activated carbon filter is disposed in the inner layer of the first purification unit, and the HEPA filter is disposed in the outer layer of the first purification unit. A gas sterilization channel is provided between the activated carbon filter and the HEPA filter. The ozone generating module or chlorine dioxide generating module is disposed at the end of the first purification unit, so that the generated ozone or chlorine dioxide can enter the gas sterilization channel. This intelligent air purification method includes: setting a start-up threshold B = { b i | i =[1, n ]} is used to indicate the start-up indicators of an air purifier, where i These represent different testing items. n This indicates the total number of items tested. b i Indicates the first i The threshold for starting an item in the detection process; setting the threshold for escalation C={ c i,j | i =[1, n ], j =[1, m ]} is used to indicate the power level of an air purifier, where, j This indicates the different power levels of the air purifier. c i,j Indicates the first j The power setting is the first i The detection value of each item; set the standby threshold D={ d i | i =[1, n ]} is used to represent the standby index of an air purifier, where d i Indicates the first i The standby value of each detection item; The ambient air quality index A is continuously monitored by the detection unit. a i | i =[1, n ]},in a i Indicates the first i Detection values ​​for each item: Case 1: When any of the air quality indicators is detected... a i Below the corresponding startup threshold b i At this time, the air purifier is in standby mode; Scenario 2: When any of the air quality indicators is detected a i Higher than the corresponding startup threshold b i When the air purifier is turned on, the following steps are performed: Use the lowest power setting as the initial operating setting; After each X1 running time, the ambient air quality index A is measured. a i | i =[1, n Until the air purifier enters standby mode: Scenario 21: When any of the air quality indicators is detected a i Below the corresponding standby value d i When this happens, the air purifier enters standby mode; Scenario 22: When any of the air quality indicators is detected a i The shift threshold is lower than the next lower power level. c i,j-1 When the air purifier is running at a lower power level, it will maintain the lowest power level if the current power level is already the lowest. Scenario 23: When any of the air quality indicators is detected a i Below the upshift threshold corresponding to the current gear c i,j And it is higher than the upshift threshold corresponding to the next lower power level in the current gear. c i,j-1 At this time, the air purifier continues to operate at its current power setting; Scenario 24: When any of the air quality indicators is detected a i Higher than the upshift threshold corresponding to the current gear c i,j When the air purifier is in use, it will operate at a higher power level. If the current power level is already the highest level, it will maintain the highest power level. The intelligent air purification method also includes using a sensing unit to detect whether there is a human body in the space where the air purifier is located. When there is no human body, the second purification unit is activated. When the second purification unit is activated, the air purification system is in standby mode, and the first purification unit does not work. When the sensing unit detects the presence of a human in the space where the air purification system is located, it also obtains the distance between the human and the air purification system and sets a noise power threshold. The noise power threshold is stored in the air purification system in the form of a table. When the indoor air needs to be purified, the power is adjusted according to the distance between the human and the air purification system so that the power is less than or equal to the noise power threshold corresponding to that distance.

2. The intelligent air purification method according to claim 1, characterized in that, Obtain the current daytime and nighttime status. When it is nighttime, in scenario 21, the air purifier will no longer enter standby mode and will maintain operation at the lowest power level.

3. The intelligent air purification method according to claim 2, characterized in that, The ambient light intensity is obtained through the sensing unit, and the day and night states are obtained based on the changes in light intensity.

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