A kind of illumination detection method, module, constant light control system and method based on the reflection light of target area to be detected

Abstract

The application discloses a kind of based on the illumination detection method, module, constant light control system and method of the reflection light of target area to be detected, it is related to light response technical field.The illumination detection method includes the following steps: create a light darkroom with darkroom inner cavity on the path of the reflection light of target area to be detected;Light entrance for the reflection light of target area to be detected to enter the darkroom inner cavity is set on the light darkroom;Detection position is set on the path of the reflection light of target area to be detected entering through light entrance in darkroom inner cavity;Darkroom inner cavity side wall is provided with light-absorbing layer for absorbing light;In detection position, photosensitive detection unit for detecting weak light signal in light darkroom environment is installed;Photosensitive detection unit detects the reflection light of target area to be detected received, and outputs the electrical signal equivalent to reflect the actual illumination of target area to be detected, and the application has the advantages that the accuracy of the illumination detection method of the reflection light of target area to be detected is poor.

Description

Technical Field

[0001] This application relates to the field of light sensing, and in particular to an illuminance detection method, module, constant light control system and method based on reflected light from a target area to be detected. Background Technology

[0002] Currently, the illuminance of a light source is typically measured by placing an illuminance meter on the object in the path of the light source and obtaining the illuminance reading. However, this setup inevitably requires a distance between the light source and the illuminance meter.

[0003] To feed back the illuminance values ​​obtained from the illuminance meter to the light source and achieve intelligent control of the light source, a wireless data transmission module needs to be added to both the illuminance meter and the light source, or a data transmission cable needs to be connected between them. However, both wireless data transmission modules and data transmission cables increase the cost of existing light source feedback control, and the coordination between the illuminance meter and the light source is difficult to achieve in real-world scenarios.

[0004] To address the data transmission issue between the illuminance meter and the light source, existing solutions combine the light sensor and the light source, mounting them on the ceiling. In this case, the light sensor can only detect the ambient light intensity by receiving reflected light from objects within the environment. This makes the light sensor susceptible to the surface reflectivity of these objects, leading to a mismatch between the detection results and the actual ambient light. Therefore, current illuminance detection methods based on reflected light from the target area have too many influencing factors, resulting in poor accuracy and requiring improvement. Summary of the Invention

[0005] To improve the accuracy of current methods for detecting illuminance from reflected light, this application provides a method, module, constant light control system, and method for detecting illuminance from reflected light in a target area.

[0006] To address the existing technical problems, the purpose of this application is to provide an illuminance detection method based on reflected light from a target area to be detected, which has the advantage of accurate illuminance detection of reflected light from the target area to be detected.

[0007] Firstly, this application provides an illuminance detection method based on reflected light from a target area to be detected, employing the following technical solution: An illuminance detection method based on reflected light from a target area includes the following steps: Create a light-dark chamber with a dark chamber cavity along the path of the reflected light from the target area to be detected; An inlet is provided on the darkroom to allow reflected light from the target area to enter the inner cavity of the darkroom. This allows the darkroom to initially select the direction and angle of the reflected light from the target area through the inlet, while restricting the entry of other light rays. In the dark chamber, a detection position is set on the path of the reflected light from the target area to be detected entering through the light inlet; An extinction layer for absorbing light is set on the side wall of the dark chamber, so that a light-dark chamber environment is formed in the dark chamber; a photosensitive detection unit that can detect weak light signals in the light-dark chamber environment is installed at the detection position; The photosensitive detection unit detects the reflected light received from the target area to be detected and outputs an electrical signal that is equivalent to the actual illuminance of the target area to be detected.

[0008] By adopting the above technical solution, the side wall of the dark chamber blocks external light sources, so that external light sources can only enter the dark chamber cavity through the light inlet, thus achieving the filtering out of most of the light that interferes with detection. Secondly, by setting a photosensitive detection unit on the photometric channel, reflected light from the target area to be detected can be directed to the photosensitive detection unit, while interfering light rays with a large angle between the line connecting the central axis of the light inlet and the detection position cannot reach the photosensitive detection unit but instead illuminate the extinction layer. Since the extinction layer has light-absorbing properties, such interfering light rays are almost completely absorbed by the extinction layer after one or two reflections, thus creating a nearly unrelated darkroom environment. Therefore, the solution of this application can achieve the acquisition of only the reflected light from the target area to be detected in a specific direction. Although this reflected light is weak, the weak light signal can be converted into a detectable electrical signal through the weak light detection of the photosensitive detection unit, effectively providing feedback on the actual illuminance of the target area to be detected.

[0009] The detection electrical signal obtained by this method differs from existing methods that use lenses to converge and collect the brightness of reflected light from multiple angles before sending it into the light sensor. This method minimizes errors caused by differences in individual illuminated objects. By only receiving reflected light from a single illuminated object in the direction of the reflected light from the target area, the amount of information that can affect the detection result is significantly reduced. Illuminance values ​​are obtained solely from the brightness of the reflected light from a single target area, making it easier to obtain an accurate illuminance value.

[0010] Optionally, the photosensitive detection unit is configured to detect the reflected light from the target area under test in a dark current-like operating state, and output an electrical signal that is equivalent to the actual illuminance of the target area under test.

[0011] By adopting the above technical solution, the photosensitive detection unit receives extremely weak light signals in a dark room environment, and the electrical signal output by the photosensitive detection unit is a dark current signal that can accurately distinguish weak light signals.

[0012] Secondly, this application provides an illuminance detection module, which adopts the following technical solution: An illuminance detection module includes a darkroom body and a photosensitizing detection unit; The light-dark chamber body is provided with a dark chamber cavity. The light-dark chamber body is provided with an entrance for the reflected light of the target area to be detected to initially select the direction and angle. A detection position is provided in the dark chamber cavity for receiving the reflected light of the target area to be detected. The dark chamber cavity forms a photometric channel through which the reflected light of the target area to be detected passes between the entrance and the detection position. The light-dark chamber body has an extinction layer on the side wall of the inner cavity of the dark chamber for absorbing light other than the reflected light from the target area to be detected, thus forming a light-dark chamber environment in the inner cavity of the dark chamber; The photosensitive detection unit is installed on the detection position, receives the optical signal of the reflected light from the target area to be detected, and converts it into a detection electrical signal.

[0013] By adopting the above technical solution, the side wall of the dark chamber body blocks external light sources, allowing external light sources to enter the dark chamber cavity only through the light inlet. This firstly achieves the filtering out of most of the light that interferes with detection, creating a near-light-free dark chamber cavity. The extinction layer can filter out interfering light that deviates from the photometric channel. This enables the photosensitive detection unit to detect the reflected light from the target area to be detected in the specified direction. As a result, the reference in this module is simple and easy to control, making it easier to detect accurate illuminance values ​​compared to the existing method of using convex lenses to collect light, thereby improving the accuracy of detection.

[0014] Optionally: The photosensitive detection unit has a sensing surface for collecting reflected light from the target area to be detected, and the sensing surface is directly opposite the photometric channel.

[0015] By adopting the above technical solution, the photosensitive detection unit is equipped with a sensing surface to perform surface detection of the reflected light from the target area to be detected. This allows for the acquisition of as much reflected light from the target area as possible without increasing the amount of interference light received, thereby improving the detection accuracy of the photosensitive detection unit.

[0016] Optional: The sensing surface is perpendicular to the photometric channel.

[0017] By adopting the above technical solution, the vertical relationship allows the reflected light from the target area to be detected to directly hit the sensing surface, improving the efficiency of the sensing surface in acquiring light, thereby further improving the detection accuracy of the photosensitive detection unit.

[0018] Optionally: A plurality of light-absorbing baffles are provided on the inner wall of the dark chamber. The light-absorbing baffles are located at a position offset from the light metering channel, and adjacent light-absorbing baffles are spaced apart to form a space for re-absorption of light that has not been completely absorbed after refraction.

[0019] By adopting the above technical solution, if there is interference light that is not completely absorbed, the incompletely absorbed interference light is refracted onto the light-absorbing barrier. The setting of the light-absorbing barrier allows the interference light to enter between adjacent light-absorbing barriers after refraction. The space between adjacent light-absorbing barriers is small, forming a space for re-absorbing interference light. Therefore, the light will undergo multiple refractions in the re-absorption space, and the light will be absorbed in a shorter refraction space and a shorter time, reducing light interference.

[0020] Optionally: A reflector is provided between the light inlet and the detection position in the dark chamber, so that the reflected light from the target area to be detected enters the detection position after being reflected by the reflector.

[0021] By adopting the above technical solution and setting up the reflector, the detection position can be set anywhere in the light-dark room according to actual needs.

[0022] Optionally: the end of the photometric channel closest to the sensing surface is perpendicular to the sensing surface.

[0023] By adopting the above technical solution, the perpendicular relationship between the photometer channel and the sensing surface allows the reflected light from the target area to be detected to directly hit the sensing surface, improving the efficiency of the sensing surface in acquiring light, thereby further improving the detection accuracy of the photosensitive detection unit.

[0024] Optionally: the light inlet and the detection position are arranged opposite each other, and the detection position is slidably arranged in the dark chamber along the central axis of the light inlet.

[0025] By adopting the above technical solution, the detection light can be adjusted by sliding the position of the detection position, making it suitable for more diverse scenarios.

[0026] Optional: The diameter of the light inlet of the darkroom is adjustable.

[0027] By adopting the above technical solution, the light inlet is preliminarily filtered by adjusting the diameter of the light inlet, and the light entering the dark chamber is adjusted to adapt to more diverse scenarios.

[0028] Optionally: The photosensitive detection unit includes: The photoelectric detection unit is used to acquire optical signals and output them as photocurrent signals. The amplification and processing unit acquires the photocurrent signal, converts and amplifies it to output a detection electrical signal.

[0029] By adopting the above technical solution, the photoelectric detection unit can identify weak light changes and output a proportional current. That is, the photoelectric detection unit will output a dark current in the dark environment and a bright current in the light environment. The setting of the dark chamber in this application effectively controls the brightness of the light illuminating the photoelectric detection unit. The amplification and processing unit can convert the current into a voltage signal that can be controlled and identified. Therefore, through the above conversion, the magnitude of reflected light in the target area of ​​weak light can be detected.

[0030] Optionally: The amplification and processing unit includes an operational amplifier U and a feedback resistor R. The output terminal of the photoelectric detection unit is connected to the inverting input terminal of the operational amplifier U. The feedback resistor R is connected between the inverting input terminal and the amplified output terminal of the operational amplifier U. The amplified output terminal of the operational amplifier U is used to output the voltage signal to be measured.

[0031] By adopting the above technical solution, the operational amplifier U and the feedback resistor R can convert the current signal at the inverting input terminal into an amplified voltage signal to be measured.

[0032] Optionally, the photosensitive detection unit further includes: The filtering unit is used to filter out interference signals present in the detected electrical signal by bandpass filtering.

[0033] By adopting the above technical solution, the filtering unit will filter out the interference signals present in the detected electrical signal, thereby improving the accuracy of the output electrical signal.

[0034] Optionally: The inner wall of the dark chamber is provided with a first interference zone where the interference light entering the dark chamber through the light inlet is directly incident, a second interference zone to which the interference light is reflected through the first interference zone, and a third interference zone to which the interference light is reflected through the second interference zone; the detection position is offset from the first interference zone, the second interference zone, and the third interference zone.

[0035] By adopting the above technical solution, and by staggering the detection position from the first interference region, the second interference region, and the third interference region, the interference light must be reflected at least three times before it can illuminate the photosensitive detection unit of the detection position. Since the light absorption rate of the current extinction layer is generally above 90%, the interference of the interference light on the reflected light of the target area to be detected can be almost negligible through the three absorptions of the side wall of the dark chamber.

[0036] Optional: The darkroom cavity has a symmetrical structure.

[0037] By adopting the above technical solution, the symmetrical structure design enables the interference light input at the detection position to be laid out more evenly and is easier to filter out.

[0038] Optionally, the dark chamber cavity is arc-shaped or polygonal along the cross-section of the photometric channel.

[0039] By adopting the above technical solution, the inner wall of the darkroom is designed in an arc or polygon shape, making it easier to control the position of reflected light.

[0040] Optionally: The light-dark chamber forms a dividing angle with the central axis of the light inlet as the center line, so that light within the dividing angle can enter the inner cavity of the dark chamber, while light outside the dividing angle cannot enter the inner cavity of the dark chamber; the light within the dividing angle is all reflected light from the target area to be detected.

[0041] By adopting the above technical solution, the resulting separation isolates and filters out other stray light rays and diffusely reflected light rays from the target area, thereby improving the uniqueness and limitation of the reflected light rays from the target area and thus improving detection accuracy.

[0042] Optional: The matting layer is a light-absorbing coating.

[0043] By adopting the above technical solution, the light-absorbing coating is made by spraying paint, and the existing light-absorbing paint can achieve a maximum light absorption rate of over 99%, thus achieving a good light filtering effect.

[0044] Optional: The matting layer is uniformly covered with light-absorbing protrusions.

[0045] By adopting the above technical solution, the light-absorbing protrusions can increase the number of reflections of stray light on the sidewall of the matting layer, thereby further improving the light absorption rate of the matting layer.

[0046] Optional: The light-dark chamber is equipped with a dust-proof and light-transmitting sheet at the light inlet.

[0047] By adopting the above technical solution, the dustproof and light-transmitting sheet can transmit light and isolate external dust, preventing external dust from entering the dark room and avoiding diffuse reflection in the dark room.

[0048] Optionally: The dustproof and light-transmitting sheet is provided with an opaque area and a light-transmitting area, wherein the light-transmitting area is located at the center of the dustproof and light-transmitting sheet to form the light inlet.

[0049] By adopting the above technical solution, the size of the light inlet can be adjusted by setting different sizes of opaque and transparent areas on the dustproof and light-transmitting sheet. Different specifications of dustproof and light-transmitting sheets can be produced and replaced according to different testing environments, which not only makes it convenient to adjust the size of the light inlet, but also saves production costs.

[0050] Optionally, the illuminance detection module further includes a housing, which is connected to the darkroom body, and the photosensitive detection unit is installed in the darkroom body using the housing.

[0051] By adopting the above technical solution, the photosensitive detection unit is installed in the darkroom body using a housing, which facilitates the assembly of the photosensitive detection unit.

[0052] Optionally: the housing and the main body of the light-dark chamber are connected and fixed by snaps and slots; Optionally, the housing is detachably connected to the main body of the darkroom.

[0053] By adopting the above technical solutions, both the fixed connection of the buckle and the slot and the detachable connection can reduce the assembly difficulty of the housing and the light-dark chamber body, and the separate design of the housing and the light-dark chamber body can also simplify the production process.

[0054] Optionally, the darkroom body is provided with an installation structure on its outer side. The installation structure includes an extension on the darkroom body and a fixing ring detachably connected to the outer side of the darkroom body. A clamping space is formed between the extension and the fixing ring.

[0055] By adopting the above technical solution, the extension and fixing ring in the installation structure can make it easier to install the darkroom body in the area to be tested. The clamping space can be used to place the darkroom body relatively stably, reducing the influence of other environmental factors on the darkroom body during the test and improving the accuracy of illuminance detection.

[0056] Optional: A soft washer is connected to the extension.

[0057] By adopting the above technical solution, the soft gasket can increase the friction with the clamped object, ensuring the stability of the connection between the light and dark chamber body and the light and dark chamber body. At the same time, it can also reduce the wear of the light and dark chamber body and ensure its service life. In the process of illuminance detection, it also has the effect of shock absorption, which can reduce the impact of vibration forces in the external environment on the light and dark chamber body and improve the detection accuracy.

[0058] Thirdly, this application provides a constant light control system, which adopts the following technical solution: A constant light control system includes an illuminance detection module as described in the second aspect, and also includes a control module and at least one lighting fixture. The illuminance detection module is connected to the control module and is used to output a detection electrical signal to the control module; The control module has a preset target brightness value. Based on the acquired detection electrical signal and the target brightness value, the control module outputs a control electrical signal to adjust the brightness of the lighting fixture to the target brightness. The lighting fixture is connected to the control module, and the lighting fixture outputs a corresponding brightness based on the control electrical signal input to the control module.

[0059] By adopting the above technical solution, the constant light system uses the illuminance detection module to detect the brightness as the real-time brightness input to the control module, and the output brightness of the lighting fixtures changes the real-time brightness; while the brightness detected by the detection module is affected by ambient light and the output light of the lighting fixtures.

[0060] During operation, the control module compares the difference between the real-time brightness and the target brightness, and controls the brightness of the lighting fixtures to gradually change the output brightness of the fixtures toward the target brightness. Since the illuminance detection module in this application has higher accuracy, it can also accurately identify the impact of changes in ambient light on the overall illuminance in the constant light control of the technical solution. At the same time, it can also accurately change the output brightness of the lighting fixtures, thereby achieving more accurate control over the target brightness.

[0061] Optionally, it also includes a light homogenizing unit, which is disposed on the light measurement channel and is used to transmit the light to be measured after light homogenization to the illuminance detection module.

[0062] By adopting the above technical solution, the setting of the light homogenizing section can improve the more accurate relationship between the illuminance of the light entering the illuminance detection module and environmental changes; therefore, the light homogenizing section will not have specular reflection and will not be greatly affected by the angle of entry of ambient light, so as to ensure the accuracy of illuminance detection by the illuminance detection module.

[0063] Optionally, it may also include a controlled terminal, which is connected to the control module and controlled by the control module to output control electrical signals.

[0064] Optionally, the control module transmits control electrical signals and / or receives control commands through a wireless transmission module.

[0065] Optional: The illuminance detection module and control module operate in low power mode to accommodate battery power.

[0066] Fourthly, this application provides a constant light control method, which adopts the following technical solution: A control method for the constant light control system described in the third aspect includes, Obtain the correlation curve between the current detected electrical signal and the actual illuminance value; Based on the comparison between the current detected electrical signal and the target brightness value, an adjustment control electrical signal is output.

[0067] Optionally: Adjusting the control electrical signal based on the comparison result between the current detected electrical signal and the target brightness value includes: The relationship curve between the output value of the control electrical signal and the actual brightness value corresponding to the detected electrical signal is obtained based on self-learning. The difference in the detected electrical signal is obtained based on the comparison results; Based on the correlation curve of the difference in detected electrical signals, the difference in the control electrical signal to be compensated is obtained. The target control signal value is determined based on the difference in control signals. Based on the determined target control signal value, the control signal is adjusted.

[0068] Optionally: Adjusting the control electrical signal based on the comparison result between the current detected electrical signal and the target brightness value includes: The difference in control electrical signals is determined based on the comparison results; The control signal adjustment value is determined based on the difference in control signals. Read the detection electrical signal to determine whether the target brightness value has been reached. If yes, the adjustment is completed. If no, obtain the comparison result and return to the step of determining the difference in control electrical signal based on the comparison result.

[0069] In summary, this application includes at least one of the following beneficial technical effects: (1) By blocking external light sources, interference light that deviates from the photometric channel is filtered out; the photosensitive detection unit detects only the reflected light of the target area to be detected in the specified direction, so as to realize the simple and easy control of the reference environment in this module, and it is easier to detect accurate illuminance values ​​compared with the existing scheme.

[0070] (2) The weak light detection and output detection voltage are different from the existing potentiometer light sensor. Although the detection result parameters are small, the detection result is accurate due to the dark current characteristics of the photoelectric detection unit. Attached Figure Description

[0071] Figure 1 A flowchart illustrating the illuminance detection method based on reflected light from the target area is shown. Figure 2 A front view of the structure of the darkroom in the illuminance detection module based on reflected light is shown. Figure 3 It is illustrated Figure 2 Schematic diagram of the structural cross section along the AA direction; Figure 4 An exploded view of the structure of the anechoic chamber in the illuminance detection module based on reflected light is shown. Figure 5 It is illustrated Figure 4 Structural diagrams from different perspectives; Figure 6 A cross-sectional view of the structure of the darkroom in the illuminance detection module based on reflected light is shown in an embodiment with cavity walls and a condenser lens. Figure 7 It is illustrated Figure 6 Explosion-proof diagram of the structure of the medium-light anechoic chamber; Figure 8 A three-dimensional view of the structure of the darkroom in the spherical embodiment of the illuminance detection module based on reflected light is shown. Figure 9 It is illustrated Figure 8 Schematic diagram of the structural cross section along the BB direction; Figure 10 A schematic diagram of light refraction is shown in a spherical embodiment of the darkroom structure in the illuminance detection module based on reflected light. Figure 11a A schematic diagram of the arc-shaped inner wall of the darkroom half in the illuminance detection module based on reflected light is shown. Figure 11b A schematic diagram is shown of the structure of the dark chamber half of the illuminance detection module based on reflected light, where the inner wall is arc-shaped and the detection position is moved forward of the light metering channel; Figure 11c A schematic diagram is shown of the structure of the dark chamber half in the illuminance detection module based on reflected light, where the inner wall is arc-shaped and the detection position is moved back from the light metering channel; Figure 11d A schematic diagram of a darkroom half in a light-reflection-based illuminance detection module is shown, illustrating an arc-shaped inner wall and a detection position located in the center of the darkroom cavity. Figure 11e A schematic diagram is shown of the structure of the dark chamber half of the illuminance detection module based on reflected light, where the inner wall is arc-shaped and there is an angle between the detection position and the light inlet. Figure 11f A schematic diagram of the cone-shaped cross-section of the inner wall of the dark chamber in the illuminance detection module based on reflected light is shown. Figure 11g A schematic diagram of the isosceles trapezoidal shape of the inner wall cross-section of the dark chamber in the illuminance detection module based on reflected light is shown. Figure 11h A schematic diagram of the structure of the dark chamber in the illuminance detection module based on reflected light, showing that the inner wall cross-section is a regular quadrilateral shape; Figure 11i A schematic diagram of the structure of the dark chamber in the illuminance detection module based on reflected light, showing that the inner wall cross-section is in the shape of a regular pentagon; Figure 11j A schematic diagram of the structure of the dark chamber in the illuminance detection module based on reflected light, showing that the inner wall cross-section is a regular hexagon; Figure 11k A schematic diagram of the structure of the dark chamber in the illuminance detection module based on reflected light, showing that the inner wall cross-section is a regular heptagon; Figure 11l A schematic diagram illustrating the adjustable detection position in an illuminance detection module based on reflected light is shown. Figure 11mA schematic diagram of an adjustable entrance aperture structure is shown in an illuminance detection module based on reflected light. Figure 11n A schematic diagram of the structure of the extinction layer with light-absorbing protrusions in the illuminance detection module based on reflected light is shown; Figure 12 A schematic diagram of the photosensitive detection unit in the illuminance detection module based on reflected light is shown. Figure 1 ; Figure 13 The basic circuit diagram of the photosensitive detection unit in the illuminance detection module based on reflected light is shown. Figure 14 A schematic diagram of the photosensitive detection unit in the illuminance detection module based on reflected light is shown. Figure 2 ; Figure 15 A schematic diagram of the constant light control system is shown. Figure 1 ; Figure 16 A schematic diagram of the constant light control system is shown. Figure 17 A schematic diagram of the constant light control system is shown. Figure 2 ; Figure 18 A flowchart illustrating the constant light control method is provided. Figure 19 The flowchart illustrates the process of adjusting the control electrical signal in the constant light control method. Figure 1 ; Figure 20 A schematic diagram showing the relationship between the brightness values ​​corresponding to the detection electrical signal and the control electrical signal is presented. Figure 21 A schematic diagram showing the relationship between the target brightness value, the ambient brightness value, and the reference brightness value is presented. Figure 22 The flowchart illustrates the process of adjusting the control electrical signal in the constant light control method. Figure 2 .

[0072] Reference numerals: 10. Dark chamber body; 101. Extension; 102. External thread; 103. Cavity wall; 11. Light inlet; 12. Partition; 121. Detection position; 13. Dark chamber cavity; 14. Metering channel; 15. Matting layer; 16. Dustproof light-transmitting sheet; 161. Opaque layer; 17. Mounting step; 18. Through hole; 19. Guide groove; 20. Electronic circuit board; 21. Photosensitive detection unit; 211. Photoelectric detection unit; 212. Amplification and processing unit; 213. Filter unit 1. Element; 22. Conductive terminal; 30. Housing; 31. Base plate; 311. Power interface; 32. Enclosure; 33. Buckle plate; 331. Lug; 34. Spacing; 40. Fixing ring; 50. Soft washer; 60. Condensing lens; 70. Darkroom body; 80. Mask; 90. Light-absorbing barrier; 100. Illumination detection module; 200. Control module; 300. Lighting fixture; 400. Light-diffusing unit; 500. Controlled terminal; 600. Wireless transmission module; 700. Wireless receiving module. Detailed Implementation

[0073] The following is in conjunction with the appendix Figure 1-22 This application will be described in further detail.

[0074] Currently, the illuminance of a light source is typically measured by placing an illuminance meter on the object in the path of the light source and obtaining the illuminance reading. However, this setup inevitably requires a distance between the light source and the illuminance meter.

[0075] To feed back the illuminance values ​​obtained from the illuminance meter to the light source and achieve intelligent control of the light source, a wireless data transmission module needs to be added to both the illuminance meter and the light source, or a data transmission cable needs to be connected between them. However, both wireless data transmission modules and data transmission cables increase the cost of existing light source feedback control, and the coordination between the illuminance meter and the light source is difficult to achieve in real-world scenarios.

[0076] To address the data transmission issue between the lux meter and the light source, existing solutions combine the light sensor and the light source, mounting them on the ceiling. In this case, the light sensor can only detect the ambient light level by receiving reflected light from objects within the environment. This makes the light sensor susceptible to the surface reflectivity of these objects, leading to a mismatch between the measured results and the actual ambient light.

[0077] Specifically, the types of objects in the environment being illuminated are diverse. For example, in an office environment, objects could be desks, A4 paper placed on the desk, keyboards, mobile phone screens, etc. The surfaces of the desk, A4 paper, keyboard, and mobile phone screen have different reflectivities due to their materials and colors. If the ambient light level remains constant, the light sensor will receive different, even contradictory, detection results from the reflected light from these surfaces. Clearly, the detection results of the existing smart lighting fixture's light sensor are easily interfered with by objects present in the environment.

[0078] Currently, to address the challenge of maintaining illumination from diverse objects in an environment, existing light sources typically incorporate lenses to converge and collect reflected light from multiple angles, directing it into the light sensor. This aims to minimize errors caused by variations in the brightness of individual illuminated objects.

[0079] Furthermore, current light sensor readings are adjusted by potentiometers, which are typically composed of a sliding rheostat. This rheostat adjusts the reading by changing the relative position between a resistive element and a movable brush. This method introduces errors into the light sensor's readings. In other words, even if the potentiometer is adjusted to the same setting as before, changes in the external environment can still affect the light sensor's readings, making existing light sensors prone to inconsistencies.

[0080] To address the aforementioned problems, this application provides an illuminance detection method based on reflected light from the target area to be detected, such as... Figure 1 As shown, it includes the following steps: A1. Create a light-dark chamber body 10 with a dark chamber cavity 13 on the path of the reflected light in the target area to be detected; The target area to be tested is set by the tester according to the actual application scenario. The reflected light from the target area is the light ray that determines the object being tested and the reflected light path. It is best to use a light source that has undergone uniform light treatment rather than a specular reflection light source, so that the illuminance of the reflected light from the target area is mainly affected only by the brightness of the external light source.

[0081] Meanwhile, the side walls of the created darkroom body 10 are made of non-transparent material, so that external light cannot pass through the side walls of the darkroom body 10 to enter the darkroom cavity 13, thereby creating an almost lightless environment in the darkroom cavity 13 of the darkroom body 10 without interference from light.

[0082] A2. An inlet 11 is provided on the main body 10 of the light-dark chamber to allow the reflected light from the target area to be tested to enter the inner cavity 13 of the dark chamber, so that the main body 10 of the light-dark chamber can make preliminary selection of the direction and angle of the reflected light from the target area to be tested through the inlet 11, and restrict the entry of other light rays. The dark chamber body 10 forms a dividing angle with the central axis of the light inlet 11 as the center line, allowing light within the dividing angle to enter the dark chamber cavity 13, while preventing light outside the dividing angle from entering the dark chamber cavity 13. This pre-filters most of the light other than the reflected light from the target area in terms of direction and angle. Therefore, the light entering the dark chamber body 10 is very weak. This ensures that even after the reflected light from the target area enters the dark chamber body 10, the dark chamber cavity 13 of the dark chamber body 10 remains in a near-lightless environment.

[0083] A3. Set the detection position 121 on the path of the reflected light in the target area to be detected in the dark chamber 13; Specifically, after determining the path of the reflected light from the target area to be detected, the light inlet 11 is positioned directly opposite the reflected light from the target area, ensuring that the emitted light enters the cavity directly into the chamber. Then, the reflected light from the target area directly illuminates the detection position 121 along its path. This ensures that even the weak reflected light from the target area is fully irradiated onto the detection position 121, guaranteeing the accuracy of the detection.

[0084] A4. An extinction layer 15 for absorbing light is provided on the side wall of the dark chamber 13, thereby creating a light-dark chamber environment in the dark chamber 13. A photosensitive detection unit 21 capable of detecting weak light signals in the light-dark chamber environment is installed on the detection position 121. Specifically, since the light inlet 11 has a width, in actual situations, in addition to the reflected light from the target area to be detected, some interference light with a small angle to the light path to be measured can also enter the dark chamber 13. Because there is an angle between such interference light and the light path to be measured, most of the interference light cannot illuminate the photosensitive detection unit 21 on the test position, but instead shines directly onto the side wall of the dark chamber 13. Since the extinction layer 15 in this application has light-absorbing characteristics, such interference light is almost completely absorbed by the extinction layer 15 after one or two reflections, thereby realizing the formation of a nearly light-dark chamber environment in the dark chamber 13.

[0085] A5. The photosensitive detection unit 21 detects the reflected light received from the target area to be detected and outputs an electrical signal that is equivalent to the actual illuminance of the target area to be detected.

[0086] The photosensitive detection unit detects weak light signals and, operating in a state approaching dark current, triggers the output of a similarly dark current signal. This enables accurate detection of weak light in complete darkness.

[0087] In summary, the detection electrical signal obtained by the illuminance detection method based on the reflected light from the target area differs from existing methods that use lenses to converge and collect the brightness of reflected light from multiple angles before sending it to the light sensor. This minimizes errors caused by differences in individual illuminated objects. By only receiving the reflected light from a single illuminated object in the direction of the reflected light from the target area, the amount of information that can affect the detection result is significantly reduced. Illuminance values ​​are obtained solely from the brightness of the reflected light from a single target area, making it easier to obtain an accurate illuminance value.

[0088] This application also provides an illuminance detection module based on reflected light.

[0089] like Figure 2 and Figure 3 As shown, an illuminance detection module based on reflected light is specifically a darkroom structure. The darkroom structure includes a darkroom body 10, an electronic circuit board 20, and a housing 30. The electronic circuit board 20 is installed in the darkroom body 10 and is fixed in the darkroom body 10 by the housing 30. The darkroom body 10 is provided with a light inlet 11 for the reflected light from the target area to be detected to enter. The side walls of the darkroom body 10 are opaque, which can block external light sources, so that external light sources can only enter the darkroom body 10 through the light inlet 11, thus filtering out most of the light that interferes with the detection.

[0090] like Figure 3 As shown, a partition 12 is provided inside the darkroom body 10. In this embodiment, the partition 12 is integrally formed with the darkroom body 10, and the partition 12 divides the darkroom body 10 into a first region and a second region. In this embodiment, the first region and the second region are distributed vertically. In other embodiments, the first region and the second region may also be distributed horizontally.

[0091] like Figure 3 As shown, the second region is a dark chamber cavity 13, with the light inlet 11 connected to the dark chamber cavity 13. The reflected light from the target area to be detected enters the dark chamber cavity 13 through the light inlet 11. An extinction layer 15 for absorbing light is provided on the side wall of the dark chamber cavity 13.

[0092] like Figure 3As shown, a detection position 121 is provided on the partition 12. The detection position 121 is specifically configured as a detection unit mounting port. In other embodiments, the detection position 121 can also be configured as a detection mounting base or detection mounting slot, or other structural forms. The detection position 121 is positioned opposite to the light inlet 11 and is used to receive reflected light from the target area to be detected. A photosensitive detection unit 21 is provided on the electronic circuit board 20 and is mounted in the detection unit mounting port. In this embodiment, the photosensitive detection unit 21 is specifically configured as a photocell, used to receive reflected light from the target area to be detected and convert the received reflected light into a readable electrical signal. A photometric channel 14 is formed between the light inlet 11 and the detection position 121, through which the reflected light from the target area to be detected passes. The reflected light is transmitted to the photosensitive detection unit 21 via the photometric channel 14.

[0093] In practice, the material of the darkroom body 10 can be either opaque or translucent, with a light-shielding layer applied or added to the outer wall to achieve a good opacity effect. Simultaneously, the light inlet 11 filters out most of the light except for the reflected light from the target area. The extinction layer 15 filters out interfering light deviating from the photometric channel 14, thus ensuring that the photosensitive detection unit 21 detects the reflected light from the target area in the specified direction. This makes the reference in this module simple and easy to control, and compared to the existing method of using convex lenses to converge light, it is easier to detect accurate illuminance values, thereby improving detection accuracy.

[0094] like Figure 3 As shown, the main body 10 of the dark chamber and the inner cavity 13 of the dark chamber are configured as a symmetrical structure symmetrically arranged with respect to the centerline of the light inlet 11. The symmetrical design of the inner cavity 13 allows for more uniform refraction of interfering light entering the inner cavity 13, making it easier to filter out.

[0095] refer to Figure 11a The main body 10 of the darkroom forms a dividing angle α with the central axis of the light inlet 11 as the center line, allowing light within the dividing angle to enter the inner cavity 13 of the darkroom, while preventing light outside the dividing angle α from entering the inner cavity 13. The light within the dividing angle α is all reflected light from the target area to be detected. This separation isolates and filters out other stray light and diffusely reflected light from the target area, improving the uniqueness and limitation of the reflected light from the target area and thus enhancing detection accuracy. Simultaneously, the actual brightness value detected by the photosensitive detection unit 21 represents the combined brightness value of the reflected light from the corresponding area of ​​the target area to be detected.

[0096] refer to Figure 11aFurthermore, the sidewall of the dark chamber 13 is provided with a first interference zone where the interfering light entering the dark chamber 13 through the light inlet 11 directly strikes the light; a second interference zone where the interfering light is reflected from the first interference zone; and a third interference zone where the interfering light is reflected from the second interference zone. The detection position 121 is offset from the first, second, and third interference zones. By offsetting the detection position 121 from the first, second, and third interference zones, the interfering light must be reflected at least three times before it can illuminate the photosensitive detection unit 21 of the detection position 121. Since the light absorption rate of the current extinction layer 15 is generally above 90%, the interference of the reflected light from the target area of ​​the interfering light can be almost negligible through the three absorptions by the sidewall of the dark chamber 13. Of course, in cases where the light absorption rate of the extinction layer 15 is increased, the detection position 121 can be offset only from the first and second interference zones. When the light absorption rate of the matting layer 15 decreases, the detection position 121 is not only set out to be offset from the first interference region, the second interference region and the third interference region, but also from the fourth interference region and even the fifth interference region.

[0097] In one embodiment, such as Figure 4 As shown, the main body 10 of the darkroom has a dustproof and light-transmitting sheet 16 at the light inlet 11, and a mounting step 17 is provided on the top of the main body 10. The dustproof and light-transmitting sheet 16 is fixedly connected to the mounting step 17. The dustproof and light-transmitting sheet 16 can transmit light and isolate external dust, preventing external dust from entering the darkroom and avoiding diffuse reflection in the darkroom.

[0098] In one embodiment, such as Figure 4 and Figure 5 As shown, in order to adjust the size of the light inlet 11 according to different detection scenarios, an opaque layer 161 is provided on the dustproof and light-transmitting sheet 16. The opaque layer 161 divides the dustproof and light-transmitting sheet 16 into an opaque area and a transparent area. The transparent area is the light inlet 11. The opaque layer 161 can be set according to the specific size of the light inlet 11. The opaque layer 161 can be an adhesive opaque layer or a coated opaque coating. The opaque layer 161 is provided at the edge of the end face of the dustproof and light-transmitting sheet 16, leaving a predetermined center position without the opaque layer 161, which serves as the light inlet 11.

[0099] In one embodiment, such as Figure 4 and Figure 5As shown, the housing 30 includes an integrally formed base plate 31, a surrounding plate 32, and a snap-on plate 33. The surrounding plate 32 and the snap-on plate 33 are protrudingly disposed below the base plate 31. The snap-on plate 33 and the surrounding plate 32 are spaced apart, that is, a gap 34 is provided between the snap-on plate 33 and the surrounding plate 32. The gap 34 separates the snap-on plate 33 and the surrounding plate 32 so that when the housing 30 is installed, the snap-on plate 33 and / or the surrounding plate 32 can deform towards the geometric center of the base plate 31 under the pressure of the light-dark chamber body 10, which facilitates the assembly of the light-dark chamber body 10 and the housing 30.

[0100] like Figure 4 and Figure 5 As shown, a lug 331 is integrally provided on the buckle plate 33, and a through hole 18 is provided on the side wall of the light-dark chamber body 10. The lug 331 engages with the through hole 18 to achieve the assembly of the light-dark chamber body 10 and the housing 30. A guide groove 19 is provided on the inner side wall of the bottom of the light-dark chamber body 10. The shape and size of the guide groove 19 match the shape and size of the lug 331. When installing the housing 30, the buckle plate 33 can be smoothly installed into the light-dark chamber body 10 under the action of the guide groove 19. The width of the buckle plate 33 is smaller than the width of the surrounding plate 32 so that the buckle plate 33 can deform under the pressure of the light-dark chamber body 10, which facilitates assembly.

[0101] like Figure 3 As shown, when the lug 331 on the buckle 33 engages with the through hole 18 on the darkroom body 10, a mounting cavity for mounting the electronic circuit board 20 is left between the bottom end of the housing 30 and the top end of the partition 12, and the electronic circuit board 20 is installed in the mounting cavity. The electronic circuit board 20 has conductive terminals 22 extending upward, and a power interface 311 is provided on the base plate 31, with the conductive terminals 22 extending into the power interface 311.

[0102] In one embodiment, such as Figure 3 As shown, to facilitate the installation of the darkroom body 10, an extension 101 is provided at the upper end of the darkroom body 10, and the width of the extension 101 is greater than the width of the darkroom body 10. An external thread 102 is provided on the outer side of the darkroom body 10, and a retaining ring 40 is provided on the outer side of the darkroom body 10. The retaining ring 40 is fitted onto the outer side of the darkroom body 10 via the external thread 102. In this embodiment, the retaining ring 40 is specifically configured as a retaining nut. A clamping space is formed between the extension 101 and the retaining ring 40, which can serve to clamp and fix the light.

[0103] When installing the darkroom body 10, a fixing plate is required. The fixing plate has mounting holes. First, the fixing ring 40 is separated from the darkroom body 10, and the darkroom body 10 is inserted into the mounting holes. Then, the fixing ring 40 is threaded onto the outside of the darkroom body 10. The clamping force of the extension 101 and the fixing ring 40 is used to fix the darkroom body 10 to the fixing plate, which is convenient for installation.

[0104] In one embodiment, such as Figure 3 As shown, to ensure greater stability of the darkroom body 10 in the detection environment, a soft washer 50 is fixedly connected to the side of the extension 101 facing the fixing ring 40. When the darkroom body 10 is mounted on the fixing plate, the soft washer 50 acts as a buffer to prevent wear on the outer side of the darkroom body 10. The soft washer 50 can deform to a certain extent, which not only increases the friction between it and the fixing plate, but also allows for a more stable connection with the fixing plate under the action of the fixing ring 40.

[0105] In one embodiment, such as Figure 6 As shown, the structure and size of the darkroom body 10, the housing 30, and the electronic circuit board 20 can be adjusted according to factors such as the required product size or the testing environment. When the overall structure of the darkroom body 10 is large, in order to ensure the light focusing effect during the testing process, a cavity wall 103 is provided inside the darkroom body 10. The cavity wall 103 encloses and forms the darkroom cavity 13, thereby reducing the volume of the darkroom cavity 13, making the light to be tested more focused, and the testing results more accurate.

[0106] In one embodiment, such as Figure 6 and Figure 7 As shown, when the ambient light level is low or the area to be detected is far from the light source, it is difficult to receive reflected light. To increase the amount of reflected light and enable its detection, a condenser lens 60 is provided inside the darkroom body 10. The condenser lens 60 is preferably a Fresnel lens, with its textured surface facing the light inlet 11. After passing through the Fresnel lens, the light is focused into the metering channel 14, enabling detection even in weak light conditions. Other types of lenses can also be used for the condenser lens 60, as long as they can achieve the focusing effect.

[0107] In one embodiment, such as Figure 8 and Figure 9 As shown, the illuminance detection module 100 can also be configured as a split structure. The illuminance detection module 100 includes a darkroom body 70 and a mask 80, which are threadedly connected. The darkroom body 70 also has a mounting cavity, and the electronic circuit board 20 is mounted on the bottom of the darkroom body 70 through a housing 30. The body and the mask 80 are interconnected, forming a darkroom cavity 13. In this embodiment, the darkroom body 70 and the mask 80 form a spherical darkroom cavity 13, causing interference light to be refracted multiple times through the sidewalls of the darkroom cavity 13. Furthermore, due to the extinction layer 15 on the inner wall of the darkroom cavity 13, the interference light is completely absorbed, thus not affecting the accuracy of the illuminance detection.

[0108] like Figure 8 and Figure 9As shown, both the main body 70 and the mask 80 of the darkroom are equipped with multiple concentric light-absorbing baffles 90 arranged around the center line of the light inlet 11. The light-absorbing baffles 90 protrude from the inner walls of the main body 70 and the mask 80. A re-absorption space is formed between adjacent light-absorbing baffles 90. Unabsorbed interference light enters between adjacent light-absorbing baffles 90, and the interference light can undergo multiple refractions in the re-absorption space. The heights of the light-absorbing baffles 90 on the main body 70 are approximately the same, allowing interference light entering the darkroom cavity 13 from the light inlet 11 to be absorbed in a shorter path and time after multiple refractions by the light-absorbing baffles 90. The heights of the light-absorbing baffles 90 on the mask 80 are not uniform; the height of the light-absorbing baffles 90 gradually decreases from the outside to the inside. That is, the light-absorbing baffle 90 located at the light inlet 11 is relatively low, so it does not affect the entry of light into the darkroom cavity 13, ensuring smooth detection of illuminance.

[0109] In one embodiment, such as Figure 11b and 11c As shown, the inner wall of the darkroom body 10 is designed with an arc shape, and the detection position 121 is directly opposite the light inlet 11. The detection position 121 can be moved forward or backward in the photometry channel 14 as needed, so as to offset the detection position 121 from the first interference region, the second interference region and the third interference region.

[0110] In one embodiment, such as Figure 11l As shown, the inner wall of the darkroom body 10 is arc-shaped, and the detection position 121 is located in the middle of the darkroom cavity 13 and is spaced apart from the inner wall of the darkroom body 10. The photosensitive detection unit is mounted on the detection position 121 by a support structure, wherein the support structure can be a connecting rod connecting the photosensitive detection unit and the side wall of the darkroom cavity 13.

[0111] In one embodiment, such as Figure 11e As shown, the inner wall of the dark chamber body 10 is arc-shaped, and there is an angle between the detection position 121 and the light inlet 11. A reflecting device is provided in the middle of the dark chamber cavity 13 to change the path of the reflected light from the target area to be detected and reflect the reflected light from the target area to the detection position 121. Preferably, the detection position 121 is located in the dark chamber cavity 13 at a 90-degree phase angle with the light inlet 11, and the reflecting device is a mirror with an angle of 45 degrees between the mirror and the central axis of the light inlet 11.

[0112] In one embodiment, such as Figure 11f As shown, the inner wall cross-section of the dark chamber body 10 is conical, the light inlet 11 is located at the head of the cone of the dark chamber body 10, and the detection position 121 is set on the side wall of the dark chamber cavity 13 and is directly opposite the light inlet 11.

[0113] In one embodiment, such as Figure 11gAs shown, the inner wall cross-section of the darkroom body 10 is an isosceles trapezoid. The light inlet 11 is located at the middle of the lower base of the isosceles trapezoid of the darkroom body 10. The detection position 121 is located at the middle of the inner wall of the upper base of the isosceles trapezoid and is directly opposite the light inlet 11.

[0114] In one embodiment, such as Figures 11h to 11k As shown, the inner wall cross-section of the darkroom body 10 is a regular polygon, which can be any regular polygon with more than 4 sides. Figure 11h and Figure 11j As shown, when the cross-section of the inner wall of the darkroom body 10 is a regular polygon with an even number of sides, the light inlet 11 is located at the middle of one side of the darkroom body 10, and the detection position 121 is located at the middle of the inner wall of the other side and is directly opposite the light inlet 11.

[0115] like Figure 11i and Figure 11k As shown, when the cross-section of the inner wall of the darkroom body 10 is a regular polygon with an odd number of sides, the light inlet 11 is located at the midpoint of the angle between the two sides of the darkroom body 10, and the detection position 121 is located at the midpoint of the inner wall of one side and directly opposite the light inlet 11.

[0116] In one embodiment, such as Figure 11m As shown, the light inlet 11 and the detection position 121 of the light-dark chamber body 10 are arranged opposite each other. The detection position 121 is slidably arranged in the light-dark chamber body 10 along the central axis of the light inlet 11, so that the photosensitive detection unit 21 can be adjusted.

[0117] In one embodiment, such as Figure 11n As shown, the light inlet 11 and the detection position 121 of the darkroom body 10 are arranged opposite each other, and the diameter of the light inlet 11 of the darkroom body 10 is adjustable to adapt to different scenarios. The diameter of the light inlet 11 is smaller than the opening size of the darkroom cavity 13, and under normal circumstances, the opening size of the darkroom cavity 13 is at least 5 times the diameter of the light inlet 11.

[0118] Furthermore, the matting layer can be integrally formed from the material that forms the darkroom, can be fixed to the inner wall of the darkroom cavity by an embedded material, or can be formed by spraying a light-absorbing coating. Preferably, the matting layer is a light-absorbing coating, so that the matting layer 15 is formed by spraying a coating, and the existing light-absorbing coatings can achieve a maximum light absorption rate of over 99%, which has a good light filtering effect.

[0119] In one embodiment, such as Figure 11n As shown, light-absorbing protrusions are evenly distributed on the matting layer 15, which increases the number of reflections of stray light on the sidewalls of the matting layer, thereby further improving the light absorption rate of the matting layer. The light-absorbing protrusions and the matting layer 15 can be integrally connected or fixedly connected by adhesive or other methods.

[0120] In one embodiment, the inner wall of the dark chamber 13 may be textured. Furthermore, such as Figure 12 As shown, the photosensitive detection unit 21 includes a photoelectric detection unit 211 and an amplification and processing unit 212. The photoelectric detection unit 211 is used to convert the light signal of the reflected light from the target area to be detected into a photocurrent signal. The amplification and processing unit 212 acquires the photocurrent signal, converts and amplifies it to output a detection electrical signal.

[0121] Specifically, the photoelectric detection unit 211 is a photodiode. A photodiode operates under reverse voltage. In the absence of light, the reverse current is extremely weak, called dark current; under light, the reverse current rapidly increases to tens of microamps, called photocurrent. The greater the light intensity, the greater the reverse current. Changes in light cause changes in the photodiode current, which converts the light signal into a photocurrent signal.

[0122] In one embodiment, such as Figure 13 As shown, the amplification and processing unit 212 includes an operational amplifier U1 and a feedback resistor R. The output terminal of the photoelectric detection unit 211 is connected to the inverting input terminal of the operational amplifier U1. The feedback resistor R is connected between the inverting input terminal and the amplified output terminal of the operational amplifier U1. The amplified output terminal of the operational amplifier U1 is used to output the voltage signal to be measured. Since the resistance value of the feedback resistor R is determined, the detection electrical signal output by the operational amplifier U1 is positively correlated with the resistance value of the feedback resistor R.

[0123] In another embodiment, such as Figure 14 As shown, the photosensitive detection unit 21 also includes a filtering unit 213, which is connected to the amplification output terminal of the operational amplifier U1 and is used to filter out any interference signals that may exist in the detection electrical signal by bandpass filtering.

[0124] Furthermore, the photosensitive detection unit 21 is shielded with a metal casing because the feedback resistance R is generally large and easily receives interference. The photosensitive detection unit 21 also has a sensing surface for collecting reflected light from the target area to be detected. The photoelectric detection unit 211 is disposed on the sensing surface, and the sensing surface is perpendicular to the photometric channel 14. This allows for the acquisition of as much reflected light from the target area as possible without increasing interference, thus improving the detection accuracy of the photosensitive detection unit 21.

[0125] This application provides a constant light control system, such as... Figure 15 and Figure 16 As shown, it includes the illuminance detection module 100 as described above, as well as a control module 200 and at least one lighting fixture 300; Illuminance detection module 100 is connected to control module 200 and is used to output detection electrical signals to control module 200. Control module 200 has a preset target brightness value. Based on the acquired detection electrical signal and target brightness value, control module 200 outputs a control electrical signal to adjust the brightness of lighting fixture 300 to the target brightness. Lighting fixture 300 is connected to control module 200 and outputs the corresponding brightness based on the control electrical signal input to control module 200.

[0126] The constant light system uses the illuminance detection module 100 to detect brightness as real-time input to the control module 200. The output brightness of the lighting fixture 300 changes the real-time brightness. The brightness detected by the detection module is affected by ambient light and the output light of the lighting fixture 300. During operation, the control module 200 compares the difference between the real-time brightness and the target brightness, and controls the change in the brightness of the lighting fixture 300 to gradually change the brightness towards the target brightness. Because the illuminance detection module 100 in this application has higher accuracy, the constant light control in the technical solution can also more accurately identify the impact of changes in ambient light on the overall illuminance, and can also more accurately change the output brightness of the lighting fixture 300, thereby achieving more accurate control of the target brightness.

[0127] Furthermore, such as Figure 15 and Figure 16 As shown, the constant light control system also includes a light homogenizing unit 400, which is positioned on the straight line of the light measurement channel 14 and is used to transmit the homogenized light to be measured to the illuminance detection module 100. Therefore, the light processed by the light homogenizing unit 400 is mainly diffuse reflection light, without specular reflection, and is therefore not significantly affected by the angle of entry of ambient light, ensuring the accuracy of illuminance detection by the illuminance detection module 100. The light within the dividing angle α is all reflected light from the light homogenizing unit 400 in the target area to be measured. The actual brightness value detected by the illuminance detection module 100 represents the combined brightness value of the reflected light from the light homogenizing unit 400 in the corresponding area of ​​the target area to be measured.

[0128] In one embodiment, such as Figure 17 As shown, the constant light control system also includes a controlled terminal 500, which is connected to the control module 200 and controlled by the control electrical signals output by the control module 200. Specifically, the controlled terminal 500 can be an electric curtain. In addition to controlling the brightness of the lighting fixtures 300, the constant light control system can also adjust the real-time brightness towards the target brightness by controlling the light sources in the shading environment.

[0129] Furthermore, a wireless transmission module 600 is provided within the control module 200, and wireless receiving modules 700 are provided in the lighting fixture 300 and the controlled terminal 500. The control module 200 transmits control electrical signals through the wireless transmission module 600 to achieve wireless control between the control module 200 and the lighting fixture 300; simultaneously, in another embodiment, the wireless transmission module 600 can receive remote control commands, facilitating remote control by the operator. In addition, since the illuminance detection module 100 operates in a state tending towards dark current, both the illuminance detection module 100 and the control module 200 operate at low power consumption to adapt to battery power supply.

[0130] Furthermore, in the constant light control system, the control module 200 can control the brightness of the lighting fixture 300 by outputting a PWM wave control electrical signal, or by adjusting the voltage value of the control electrical signal.

[0131] This application also provides a constant light control method, such as... Figure 18 As shown, it includes: S1. Obtain the correlation curve between the current detected electrical signal and the actual illuminance value; Specifically, during the self-learning process, the reference illuminance value under the first ambient light level is measured primarily using an illuminance detection device at the current uniform light distribution unit 400. Simultaneously, the illuminance detection module 100 detects and acquires the detection electrical signal of the first ambient light level; and obtains the correlation point between the reference illuminance value and the detection electrical signal under the first ambient light level. In the coordinate system where the correlation point is located, the reference illuminance value can be positioned on the Y-axis, and the detection electrical signal on the X-axis.

[0132] Then, the brightness value of the lighting fixture 300 is adjusted to change the ambient brightness of the light-diffusing unit 400. Next, a lux meter is used to measure the reference illuminance value under the second ambient brightness, and simultaneously, the illuminance detection module 100 detects and acquires the detection electrical signal for the second ambient brightness. A correlation point between the reference illuminance value and the detection electrical signal under the second ambient brightness is then constructed. This process is repeated to obtain ten to twenty correlation points between reference illuminance values ​​and detection electrical signals under significantly different ambient brightness levels, connecting them to form a correlation curve between the detection electrical signal and the actual illuminance value. Of course, in applications requiring high precision, the number of correlation points between reference illuminance values ​​and detection electrical signals under different ambient brightness levels can be increased.

[0133] After the correlation curve is obtained, the reference illuminance value can be output by converting the detection electrical signal of the current ambient brightness through the illuminance detection module 100.

[0134] S2. Based on the comparison between the current detected electrical signal and the target brightness value, adjust the control electrical signal.

[0135] Specifically, the target brightness value can be obtained by directly inputting the reference illuminance value into the terminal device; alternatively, it can be obtained by reading the current detection electrical signal and using the current detection electrical signal as the target brightness value.

[0136] Furthermore, in one case, such as Figure 19 As shown, S2, based on the comparison result between the current detected electrical signal and the target brightness value, adjusts the control electrical signal including: S201. A curve showing the relationship between the output value of the control electrical signal and the actual brightness value corresponding to the detected electrical signal, obtained through self-learning; specifically, such as... Figure 20 As shown, during the self-learning process, the illuminance detection module 100 detects and acquires the actual luminance values ​​corresponding to the first control electrical signal and the detection electrical signal; and obtains the correlation points between the actual luminance values ​​corresponding to the first control electrical signal and the detection electrical signal. In the coordinate system where the correlation points are located, the actual luminance value corresponding to the detection electrical signal is on the Y-axis, and the control electrical signal is on the X-axis.

[0137] Then, the control electrical signal input to the lighting fixture 300 is adjusted to change the ambient brightness of the light-diffusing unit 400; the illuminance detection module 100 is used to detect and acquire the detection electrical signal corresponding to the second control electrical signal; and a correlation point between the second control electrical signal and the detection electrical signal is constructed. This process is repeated to form a relationship curve between the actual brightness value corresponding to the detection electrical signal and the control electrical signal.

[0138] S202. Obtain the difference in the detected electrical signal based on the comparison results; Specifically, the difference between the target brightness value and the actual brightness value corresponding to the detection electrical signal can be obtained by comparing them.

[0139] S203. Based on the relationship curve between the output value of the control electrical signal and the detected electrical signal, obtain the difference in the control electrical signal to be compensated. Specifically, the difference in the detection electrical signal can be obtained by comparing the target brightness value with the reference illuminance value corresponding to the detection electrical signal.

[0140] S204. Determine the target control signal value based on the control signal difference; Specifically, the target control signal value is determined by mapping the difference in the detected electrical signal to the relationship curve between the voltage signal and the control electrical signal.

[0141] S205. Adjust the control signal based on the determined target control signal value.

[0142] like Figure 21 As shown, the advantage of adjusting the control signal using this method is that the number of adjustments to the control signal is small, but the disadvantage is that adjusting the control signal requires a lot of calculations.

[0143] Specifically, in another case, such as Figure 22 As shown, S3, based on the comparison result between the current detected electrical signal and the target brightness value, adjusts the control electrical signal including: S211. Determine the control signal difference based on the comparison results; Specifically, the target brightness value is compared with the reference illuminance value corresponding to the detected electrical signal to determine the difference between the current control electrical signal and the control electrical signal corresponding to the reference illuminance value.

[0144] S212. Determine the control signal adjustment value based on the control signal difference; Specifically, the control signal adjustment value is generally calculated by PID control to obtain the corresponding voltage signal adjustment value. The proportional, integral, and derivative values ​​in the PID can be adjusted according to the actual situation.

[0145] S213. Determine whether the read detection electrical signal has reached the target brightness value. If yes, complete the adjustment. Otherwise, obtain the comparison result and return to step S211.

[0146] The advantage of adjusting the control signal using this method is that it does not require a lot of calculations, but the disadvantage is that it requires adjusting the control signal many times.

[0147] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A method for detecting illuminance based on reflected light from a target area, characterized in that, Includes the following steps: A1. Create a light-dark chamber body (10) with a dark chamber cavity (13) on the path of the reflected light in the target area to be detected. A2. An inlet (11) is provided on the main body (10) of the light-dark chamber to allow the reflected light from the target area to be detected to enter the inner cavity (13) of the dark chamber, so that the main body (10) of the light-dark chamber can make a preliminary selection of the direction and angle of the reflected light from the target area to be detected through the inlet (11) and restrict the entry of other light rays. A3. In the dark chamber cavity (13), a detection position (121) is set on the path of the reflected light from the target area to be detected entering through the light inlet (11). The dark chamber cavity (13) forms a photometric channel (14) between the light inlet (11) and the detection position (121) through which the reflected light from the target area to be detected passes. When the path of the reflected light from the target area to be detected is determined, the light inlet (11) is directly facing the reflected light from the target area to be detected, so that the emitted light to be detected can enter the chamber cavity directly. Then the reflected light from the target area to be detected is directly incident on the detection position (121) along the path of the photometric channel (14). A4. An extinction layer (15) for absorbing light is provided on the side wall of the dark chamber (13) so that a light-dark chamber environment is formed in the dark chamber (13); a photosensitive detection unit (21) that can detect weak light signals in the light-dark chamber environment is installed on the detection position (121); the extinction layer (15) can filter out interfering light that deviates from the light measurement channel (14); A5. The photosensitive detection unit (21) detects the reflected light received from the target area to be detected and outputs an electrical signal that is equivalent to the actual illuminance of the target area to be detected; wherein, the photosensitive detection unit (21) is set to detect the reflected light received from the target area to be detected in a working state that tends to dark current and outputs an electrical signal that is equivalent to the actual illuminance of the target area to be detected. The illuminance detection module (100) used by the photosensitive detection unit (21) is a split structure including a darkroom body (70) and a mask (80) to form the darkroom cavity (13), so that the interference light is refracted multiple times through the side wall of the darkroom cavity (13); the darkroom body (70) and the mask (80) are each provided with a number of concentric light-absorbing baffles (90) with the center line of the light inlet (11) as the axis, protruding from the inner walls of the darkroom body (70) and the mask (80). The height of the light-absorbing baffles (90) on the darkroom body (70) is the same, while the height of the light-absorbing baffles (90) on the mask (80) is inconsistent, and the height gradually decreases from the outside to the inside. The adjacent light-absorbing baffles (90) are spaced apart to form a space for the re-absorption of light after refraction that has not been completely absorbed.

2. An illuminance detection module based on reflected light, characterized in that, It includes a darkroom body (10) and a photosensitive detection unit (21); The dark chamber body (10) is provided with a dark chamber cavity (13). The dark chamber body (10) is provided with an inlet (11) for initially selecting the reflected light of the target area to be detected in terms of direction and angle. The dark chamber cavity (13) is provided with a detection position (121) for receiving the reflected light of the target area to be detected. The dark chamber cavity (13) forms a photometric channel (14) between the inlet (11) and the detection position (121) for the reflected light of the target area to be detected to pass through. When the path of the reflected light of the target area to be detected is determined, the inlet (11) is directly facing the reflected light of the target area to be detected, so that the emitted light to be detected can enter the inner cavity of the chamber directly. Then the reflected light of the target area to be detected is directly incident on the detection position (121) along the path of the photometric channel (14). The light-dark chamber body (10) has an extinction layer (15) on the side wall of the dark chamber cavity (13) for absorbing light other than the reflected light of the target area to be detected, thus forming a light-dark chamber environment in the dark chamber cavity (13); the extinction layer (15) can filter out interfering light that deviates from the light measurement channel (14); The photosensitive detection unit (21) is installed on the detection position (121), receives the light signal of the reflected light from the target area to be detected and converts it into a detection electrical signal; The photosensitive detection unit (21) has a sensing surface for collecting reflected light from the target area to be detected, and the sensing surface is directly opposite the photometric channel (14); the photosensitive detection unit (21) is set to detect the reflected light from the target area to be detected in a dark current-prone working state, and outputs an electrical signal that is equivalent to the actual illuminance of the target area to be detected. The illuminance detection module is a split structure comprising a darkroom body (70) and a mask (80) to enclose the darkroom cavity (13), so that interference light is refracted multiple times through the sidewall of the darkroom cavity (13). The inner walls of the darkroom body (70) and the mask (80) are provided with a plurality of concentric light-absorbing baffles (90) with the center line of the light inlet (11) as the axis, protruding from the inner walls of the darkroom body (70) and the mask (80). The height of the light-absorbing baffles (90) on the darkroom body (70) is the same, while the height of the light-absorbing baffles (90) on the mask (80) is inconsistent, gradually decreasing from the outside to the inside. Adjacent light-absorbing baffles (90) are spaced apart to form a space for re-absorption of light that has not been completely absorbed after refraction.

3. The illuminance detection module based on reflected light according to claim 2, characterized in that: The light inlet (11) and the detection position (121) are arranged opposite each other. The detection position (121) is arranged in the dark chamber body (10) and can slide along the central axis of the light inlet (11).

4. The illuminance detection module based on reflected light according to claim 2, characterized in that: The light inlet (11) of the main body (10) of the light-dark chamber is adjustable in diameter.

5. The illuminance detection module based on reflected light according to claim 2, characterized in that: The photosensitive detection unit (21) includes: The photoelectric detection unit (211) is used to acquire optical signals and output them as photocurrent signals; The amplification and processing unit (212) acquires the photocurrent signal and converts and amplifies it to output the detection electrical signal.

6. The illuminance detection module based on reflected light according to claim 5, characterized in that: The amplification and processing unit (212) includes an operational amplifier U1 and a feedback resistor R. The output terminal of the photoelectric detection unit (211) is connected to the inverting input terminal of the operational amplifier U1. The feedback resistor R is connected between the inverting input terminal and the amplified output terminal of the operational amplifier U1. The amplified output terminal of the operational amplifier U1 is used to output the voltage signal to be measured.

7. The illuminance detection module based on reflected light according to claim 5, characterized in that: The photosensitive detection unit (21) further includes a filtering unit (213), which is used to filter out interference signals present in the detection electrical signal by bandpass filtering.

8. The illuminance detection module based on reflected light according to claim 2, characterized in that: The inner cavity (13) of the dark chamber is a symmetrical structure with the central axis of the light inlet (11) as the axis of symmetry.

9. The illuminance detection module based on reflected light according to claim 8, characterized in that: The dark chamber (13) is arc-shaped or polygonal in cross-section along the light metering channel (14).

10. The illuminance detection module based on reflected light according to claim 2, characterized in that: The light-dark chamber body (10) forms a dividing angle with the central axis of the light inlet (11) as the center line, so that the light within the dividing angle can enter the dark chamber cavity (13), and the light outside the dividing angle cannot enter the dark chamber cavity (13); the light within the dividing angle is all reflected light from the target area to be detected.

11. The illuminance detection module based on reflected light according to claim 2, characterized in that: The matting layer (15) is a light-absorbing coating, and light-absorbing protrusions are evenly distributed on the matting layer (15).

12. The illuminance detection module based on reflected light according to claim 2, characterized in that: The main body (10) of the light-dark chamber is provided with a dustproof and light-transmitting sheet (16) at the light inlet (11); or / and, the dustproof and light-transmitting sheet (16) is provided with an opaque area and a light-transmitting area, the light-transmitting area being located at the center of the dustproof and light-transmitting sheet (16) to form the light inlet (11).

13. The illuminance detection module based on reflected light according to claim 2, characterized in that: It also includes a housing (30), which is connected to the light-dark chamber body (10), and the photosensitive detection unit (21) is installed in the light-dark chamber body (10) using the housing (30).

14. The illuminance detection module based on reflected light according to claim 13, characterized in that: The housing (30) and the light-dark chamber body (10) are connected and fixed by buckles and slots; the housing (30) and the light-dark chamber body (10) are detachably connected.

15. The illuminance detection module based on reflected light according to claim 2, characterized in that: An installation structure is provided on the outside of the light-dark chamber body (10). The installation structure includes an extension (101) provided on the light-dark chamber body (10) and a fixing ring (40) detachably connected to the outside of the light-dark chamber body (10). A clamping space is formed between the extension (101) and the fixing ring (40). A soft washer (50) is connected to the extension (101).

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