LED table lamp adaptive control method, system and LED table lamp

Abstract

The present application relates to the field of lighting technology, especially to a LED table lamp adaptive control method and system and a LED table lamp, wherein the method comprises: establishing a hand model; determining a target brightness interval; determining an effective lighting range of the table lamp; determining an effective light spot area; randomly selecting n sampling points in the effective light spot area; establishing an n-equation system for a single sampling point; simultaneously solving to obtain initial light intensity of each light-emitting subunit; and correcting PWM on-time proportion of each light-emitting subunit. By setting light-emitting subunits with different beam angles and orientations, the target brightness interval acting on the action plane is determined according to the environment brightness when the LED table lamp starts to operate, so that the light intensity after superposition of light of each light-emitting subunit is within the range acceptable by the human eye, thereby reducing eye fatigue caused by the table lamp during use.

Description

Technical Field

[0001] This invention relates to the field of lighting technology, and in particular to an adaptive control method, system and LED desk lamp for LED desk lamps. Background Technology

[0002] In the modern lighting field, with the improvement of people's quality of life and the pursuit of a healthy and comfortable living environment, intelligent lighting products are becoming increasingly popular. LED desk lamps, as lighting devices used very frequently in daily life, are undergoing rapid intelligentization. Intelligent LED desk lamps aim to bring users a more convenient, efficient, and ergonomic lighting experience, becoming an important direction for innovation and development in the lighting industry.

[0003] However, due to factors such as desktop layout and user habits, the placement of desk lamps varies. When a desk lamp is positioned to the side of the user, the light intensity gradually decreases with increasing distance and changes in beam angle, resulting in excessively high light intensity on one side and insufficient light intensity on the other. This uneven light intensity distribution forces the user's eyes to frequently adapt to different brightness areas, easily causing visual fatigue, and prolonged use may even damage eyesight. Furthermore, some desk lamps attempt to improve lighting effects by automatically detecting and adjusting the LED light, but during the adjustment process, the light often shines directly into the eyes, not only failing to solve the problem of visual fatigue but also introducing new discomfort, seriously affecting the user experience.

[0004] Therefore, the existing technology has defects and urgently needs improvement. Summary of the Invention

[0005] The purpose of this invention is to provide an adaptive control method, system, and lamp for LED desk lamps to solve the problems in the prior art where the light intensity is too high on one side and too low on the other side due to placement issues, and where some desk lamps attempt to improve the lighting effect by automatically detecting and adjusting the LED lamp head, but the light often shines directly into the eyes during the adjustment process.

[0006] This invention provides an adaptive control method for an LED desk lamp, comprising:

[0007] Establish a hand model for recognizing hand posture and size;

[0008] In response to the desk lamp start signal, the ambient brightness is acquired, and the target brightness range of the desk lamp is determined based on the ambient brightness.

[0009] Collect images of the user's hand, and determine the effective lighting range of the desk lamp based on the hand model and the hand images;

[0010] The effective light spot area is determined based on the effective lighting range, the spatial position of the table lamp, and the relative positional relationship of the plane of action.

[0011] Randomly select n sampling points within the effective light spot area;

[0012] For a single sampling point, based on the beam angle between the sampling point and each light-emitting sub-unit, the propagation distance between each light-emitting sub-unit and the sampling point, and the propagation loss calculation model, an n-variable equation system is established regarding the initial light intensity of each light-emitting sub-unit.

[0013] By solving the system of n equations corresponding to all sampling points, the initial light intensity of each luminous subunit can be obtained.

[0014] The PWM conduction time ratio of each light-emitting sub-unit is corrected based on the initial light intensity.

[0015] As a preferred technical solution for the adaptive control method of LED desk lamp, the hand model is constructed based on ergonomic data. When the actual size parameter value of the hand is input, the corresponding three-dimensional hand model is output.

[0016] When combined with a hand image as input, the output is a 3D model of the hand pose corresponding to the hand pose in the hand image.

[0017] As a preferred technical solution for the adaptive control method of LED desk lamps, the step of acquiring a user's hand image and determining the effective lighting range of the desk lamp based on the hand model and the hand image includes:

[0018] In response to a switch trigger signal, acquire a hand image and record it as the initial hand image;

[0019] Based on the initial hand image and the principle of linear perspective, the actual hand size parameters are calculated and obtained.

[0020] Input the actual hand size parameters into the hand model to generate a three-dimensional model of the user's hand;

[0021] Continuously collect images of the user's hands, filter out the smallest and largest hand images, and record them as boundary hand images respectively;

[0022] Identify the hand pose in the boundary hand image, input the hand pose into the hand 3D model, and output the hand pose 3D model corresponding to the hand pose;

[0023] Based on the aforementioned three-dimensional model of hand posture and the principle of linear perspective, the distance range of hand movement is calculated, and the effective lighting range is determined according to the distance range of hand movement.

[0024] As a preferred technical solution for the adaptive control method of LED desk lamps, the propagation loss calculation model is built based on the relationship between light loss and propagation distance during light propagation in the air as input data. If the propagation distance is input, the transmission loss is output.

[0025] As a preferred technical solution for the adaptive control method of LED desk lamps, the method establishes a set of n equations about the initial light intensity of each light-emitting sub-unit based on the beam angle between the sampling point and each light-emitting sub-unit, the propagation distance between each light-emitting sub-unit and the sampling point, and the propagation loss calculation model, including:

[0026] Obtain the geometric center point of all light-emitting sub-units, and draw a perpendicular line from the geometric center point to the plane of action to determine the foot of the perpendicular;

[0027] A three-dimensional rectangular coordinate system is established with the foot of the perpendicular as the origin, wherein: the point farthest from the foot of the perpendicular is selected in the effective lighting range and the direction of the line connecting it to the foot of the perpendicular is recorded as the X-axis; the direction of the line connecting the origin and the geometric center point is recorded as the Z-axis; and the Y-axis direction starts from the origin and is perpendicular to the X-axis and Y-axis planes.

[0028] The coordinates of the geometric center point and the coordinates of the sampling point are determined based on the length of the perpendicular line and the distance between the sampling point and the foot of the perpendicular.

[0029] The coordinates of each light-emitting subunit are determined based on the coordinates of the geometric center point and the relative positional relationship between each light-emitting subunit;

[0030] The propagation distance between each light-emitting sub-unit and the sampling point is determined based on the coordinates of each light-emitting sub-unit and the coordinates of the sampling point.

[0031] Based on the propagation distance and the propagation loss calculation model, the transmission loss is obtained;

[0032] Based on the beam angle, the transmission loss, and the target brightness range, establish an expression for the light intensity of all light-emitting subunits at this sampling point;

[0033] Within the effective illumination range, n sampling points are selected to obtain their corresponding light intensity expressions, and the light intensity expressions are combined to form a system of n equations.

[0034] As a preferred technical solution for the adaptive control method of LED desk lamp, the effective light spot area is: the smallest light spot area formed by the LED desk lamp on the working plane that covers the effective lighting range;

[0035] The plane of action is the plane in which the effective light spot area formed by the LED desk lamp illumination is located.

[0036] As a preferred technical solution for the adaptive control method of LED desk lamp, the beam angle is: the angle between two directions when the luminous intensity drops to 50% of the maximum luminous intensity at the center in the light source intensity distribution curve.

[0037] As a preferred technical solution for the adaptive control method of LED desk lamps, determining the target brightness range of the desk lamp based on the ambient brightness specifically includes:

[0038] A mapping table between preset ambient brightness and target brightness ranges is provided. The mapping table is constructed based on human visual comfort experimental data and includes the optimal target brightness range corresponding to different ambient brightness ranges.

[0039] The ambient brightness is compared with different ambient brightness ranges to determine the corresponding ambient brightness range;

[0040] Based on the preset mapping table between ambient brightness and target brightness range, the optimal target brightness range corresponding to the corresponding ambient brightness range is determined as the target brightness range of the desk lamp.

[0041] An adaptive control system for an LED desk lamp includes:

[0042] Modeling unit, used to create a hand model for recognizing hand posture and size;

[0043] A brightness determination unit is used to respond to a desk lamp start signal, acquire ambient brightness, and determine the target brightness range of the desk lamp based on the ambient brightness.

[0044] The range determination unit is used to acquire images of the user's hand and determine the effective lighting range of the desk lamp based on the hand model and the hand images;

[0045] The area determination unit is used to determine the effective light spot area based on the effective lighting range, the spatial position of the table lamp, and the relative positional relationship of the plane of action.

[0046] A sampling unit is used to select the farthest point and the nearest point to the desk lamp within the effective light spot area and connect them, and select n sampling points on the connecting line.

[0047] The computation unit is used to establish a set of n equations about the initial light intensity of each light-emitting sub-unit for a single sampling point, based on the beam angle between the sampling point and each light-emitting sub-unit, the propagation distance between each light-emitting sub-unit and the sampling point, and the propagation loss calculation model; and solve the set of n equations corresponding to all sampling points to obtain the initial light intensity of each light-emitting sub-unit.

[0048] The correction unit corrects the PWM conduction time ratio of each light-emitting sub-unit based on the initial light intensity.

[0049] An LED desk lamp includes: a lamp body, an LED desk lamp assembly, a sensor, a processor, a driver circuit, and a power supply.

[0050] Compared with the prior art, the beneficial effect of the present invention is that, by setting light-emitting sub-units with different beam angles and orientations, the present invention enables the LED desk lamp to determine the target brightness range acting on the action plane based on the ambient brightness when it starts running. Based on the principle of "near is larger and far is smaller" combined with the collected hand image, the effective lighting range of the lamp is determined. Since the area illuminated by the desk lamp does not change due to the shape of the effective lighting range, the effective light spot area of ​​the desk lamp acting on the action plane should be a closed area that includes the effective lighting range. At each position within this area, the light intensity after the light from each light-emitting sub-unit is superimposed is within the range acceptable to the human eye, thereby reducing eye fatigue caused by the use of the desk lamp.

[0051] Furthermore, in actual use, the performance of desk lamps varies due to environmental factors. For example, due to the width of the desktop, the lamp is positioned to the side of the user. The light intensity gradually decreases with increasing distance and beam angle. Users may experience uneven light intensity on one side and vice versa, requiring frequent eye adjustments and potentially causing eye strain. Simply automatically detecting and adjusting the LED lamp head to ensure the light intensity within the user's effective illumination area may result in direct light shining into the eyes. Therefore, simply adjusting the LED lamp head... The invention addresses the problem of eye fatigue caused by desk lamps during use by setting different beam angles for each light-emitting sub-unit. This results in different areas formed by the light emitted by each sub-unit on the action plane. For any point within the effective light spot area, the light intensity is the superposition of the light emitted by n light-emitting sub-units. By selecting n points and establishing corresponding expressions for each point, and solving the equations simultaneously, the initial light intensity of each light-emitting sub-unit can be calculated. Based on the calculation results, the initial light intensity of each light-emitting sub-unit can be corrected to ensure that the light intensity fluctuation within the effective light spot area is within the target brightness range acceptable to the human eye, thereby reducing eye fatigue caused by uneven light intensity distribution during use. Attached Figure Description

[0052] Figure 1 This is a flowchart illustrating the steps of the adaptive control method for an LED desk lamp according to an embodiment of the present invention.

[0053] Figure 2 This is a structural block diagram of the LED desk lamp adaptive control system according to an embodiment of the present invention. Detailed Implementation

[0054] The features and exemplary embodiments of various aspects of this application will be described in detail below. To make the objectives, technical solutions, and advantages of this application clearer, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only intended to explain this application and not to limit it. For those skilled in the art, this application can be implemented without some of these specific details. The following description of the embodiments is merely to provide a better understanding of this application by illustrating examples.

[0055] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus that includes said element.

[0056] Please see Figure 1 The diagram shows the steps of the adaptive control method for an LED desk lamp according to an embodiment of the present invention, including:

[0057] Step S1: Establish a hand model for recognizing hand posture and size;

[0058] Step S2: In response to the desk lamp start signal, acquire the ambient brightness and determine the target brightness range of the desk lamp based on the ambient brightness.

[0059] Step S3: Collect the user's hand image, and determine the effective lighting range of the desk lamp based on the hand model and hand image;

[0060] Step S4: Determine the effective light spot area based on the effective lighting range, the spatial position of the table lamp, and the relative positional relationship of the plane of action;

[0061] Step S5: Randomly select n sampling points within the effective light spot area;

[0062] Step S6: For a single sampling point, based on the beam angle between the sampling point and each light-emitting sub-unit, the propagation distance between each light-emitting sub-unit and the sampling point, and the propagation loss calculation model, establish a set of n equations about the initial light intensity of each light-emitting sub-unit.

[0063] Step S7: Solve the system of n equations corresponding to all sampling points to obtain the initial light intensity of each luminous subunit;

[0064] Step S8: Correct the PWM conduction time ratio of each light-emitting sub-unit according to the initial light intensity.

[0065] In the above technical solution, the beam angles of each light-emitting sub-unit are not exactly the same. Ambient brightness is detected in real time by a digital light sensor located on the top of the lamp; hand images are captured by a camera located on the base of the lamp; the target brightness range uses PWM (Pulse Width Modulation) technology to adjust the brightness by changing the proportion of current conduction time, so as to avoid LED color temperature shift.

[0066] Furthermore, based on the construction of a hand model, this invention outputs a corresponding three-dimensional hand model according to the actual collected data. By adjusting the posture of the three-dimensional hand model through gestures, it outputs a three-dimensional hand posture model that is the same as the posture in the hand image. Combining the principle of linear perspective, it determines the effective illumination range of the light source. Since the area illuminated by the lamp does not change due to the shape of the effective illumination range, the effective light spot area of ​​the lamp on the action plane should be a closed area that includes the effective illumination range. At each position within this area, the light intensity after the superposition of the light from each light-emitting sub-unit is within the range acceptable to the human eye, thereby reducing eye fatigue caused by the use of the lamp.

[0067] Furthermore, the hand model is constructed based on ergonomic data, and when the actual size parameters of the hand are input, the corresponding three-dimensional hand model is output.

[0068] When combined with a hand image as input, the output is a 3D model of the hand pose corresponding to the hand pose in the hand image.

[0069] In practice, the hand model training involves inputting 1000+ sets of ergonomic hand 3D scan data (covering people aged 15-60), using the PointNet network to train a 3D reconstruction model, and outputting a 3D hand model that includes the skeletal structure when inputting actual hand size parameters (such as palm length and width).

[0070] When combining image input: semantic segmentation (distinguishing palm, fingers, and joints) is first performed on the acquired hand image, 2D contour features are extracted, and then converted into a 3D pose model through a coordinate mapping algorithm, with the error controlled within ±2mm;

[0071] Posture-size output: When inputting posture labels such as "clenched fist" and "extended" and the original hand size, the model outputs a 3D model of the hand posture under the current posture through a preset posture-size correlation function (such as the length shortening coefficient when the fingers are bent). For example, when clenching a fist, the palm width will increase, which can be simulated by the 3D model of the hand posture.

[0072] Furthermore, the hand model is combined with 3D modeling and posture association, enabling the hand image to be adjusted according to the hand posture in the image to obtain a hand posture 3D model. This allows the model to match the hand image, and the principle of linear perspective is used to achieve accurate conversion of hand size and distance, reducing the error of relying solely on image recognition (such as size misjudgment caused by perspective deviation). This provides reliable data for subsequent calculation of the effective lighting range based on distance, ensuring that the brightness distribution is uniform within the effective lighting range after subsequent adjustment. This reduces eye fatigue caused by light intensity attenuation and increases user comfort.

[0073] Specifically, the effective illumination range of the desk lamp is determined based on the hand model and hand image, including:

[0074] In response to a switch trigger signal, acquire a hand image and record it as the initial hand image;

[0075] Based on the initial hand image and the principle of linear perspective, the actual hand size parameters are calculated and obtained.

[0076] Input the actual hand size parameters into the hand model to generate a 3D model of the user's hand;

[0077] Continuously collect images of the user's hands, filter out the smallest and largest hand images, and record them as boundary hand images respectively;

[0078] Identify the hand pose in the boundary hand image, input the hand pose into the hand 3D model, and output the hand pose 3D model corresponding to the hand pose;

[0079] Based on a 3D model of hand posture and the principle of linear perspective, the distance range of hand movement is calculated, and the effective lighting range is determined according to the distance range of hand movement.

[0080] In detail, combining the principle of linear perspective: "Known actual hand size parameters + observed projection size", the distance between the hand and the observation point is calculated (i.e., the distance measurement formula: distance = actual hand size parameters × focal length / projection size). The actual hand size parameters can be obtained by directly prompting the user to place their palm on the working plane directly below the lamp before use. Since the distance between the lamp head and the working plane can be directly measured, the distance, focal length, and projection size are all known quantities, allowing the calculation of the user's actual hand size parameters. Alternatively, an image of the hand at the moment the switch is triggered can be captured, and the hand size can be calculated based on the distance between the switch and the camera. Other measurement methods that can obtain the actual hand size parameters are also acceptable and are not limited here. After determining the distance between the hand and the observation point, the object acting on the hand (a book, computer, or other object the hand acts on during the use of the LED lamp, located between the hand and the observation point) is identified. This allows for the determination of an ellipse whose projection on the working plane completely encompasses the object acting on the hand. The area enclosed by this ellipse is recorded as the effective lighting range. It is understandable that when a desk lamp shines obliquely onto the working plane, it forms an elliptical region with the major axis of the elliptical region pointing in the direction of the desk lamp. The larger the angle between the working plane and the desk lamp, the longer the major axis. This invention determines a closed elliptical region that can contain the projection of the hand onto the working plane by determining the distance between the hand and the observation point and the object being acted upon. This determines the effective lighting range that needs to ensure uniform brightness distribution, thus providing a basis for selecting sampling points within the effective lighting range to calculate the initial light intensity. This ensures uniform brightness distribution within the user's working range during use, thereby increasing user comfort.

[0081] Specifically, the propagation loss calculation model is built based on the relationship between light loss and propagation distance during light propagation in the air as input data. If the propagation distance is input, the output is the transmission loss.

[0082] In detail, in this embodiment of the invention, the construction of the propagation loss calculation model includes the following steps:

[0083] Light intensity attenuation data were collected at different distances (0.5m to 2m, with an interval of 0.1m) through experiments. In a constant temperature (25℃) and unobstructed environment, the light intensity value of the same LED sub-unit at different distances was measured with a spectrometer, and the loss (initial light intensity - measured light intensity) was calculated.

[0084] Fitting loss formula: Based on experimental data, a quadratic function is used to fit the relationship between loss and distance: Loss = k × distance² + b (where k and b are fitting coefficients, determined by the least squares method), model error ≤ 5%;

[0085] Practical application: Input the propagation distance between a sampling point and a sub-unit (e.g., 1.2m), substitute it into the formula to directly output the loss (e.g., 18% of the initial light intensity).

[0086] Furthermore, by establishing a propagation loss calculation model, given a fixed propagation distance, the light transmission loss is directly output by inputting the propagation distance. This allows for a more accurate calculation of the initial light intensity of each light-emitting sub-unit based on the light transmission loss, increasing the uniformity of light intensity distribution within the effective illumination range, reducing eye fatigue caused by light intensity attenuation, and enhancing user comfort.

[0087] Furthermore, based on the beam angle between the sampling point and each emitting sub-unit, the propagation distance between each emitting sub-unit and the sampling point, and the propagation loss calculation model, a system of n equations concerning the initial light intensity of each emitting sub-unit is established, including:

[0088] Obtain the geometric center point of all light-emitting sub-units, draw a perpendicular line from the geometric center point to the plane of action, and determine the foot of the perpendicular;

[0089] Establish a three-dimensional rectangular coordinate system with the foot of the perpendicular as the origin, where: select the point farthest from the foot of the perpendicular within the effective lighting range and denote the direction of the line connecting it to the foot of the perpendicular as the X-axis; denote the direction of the perpendicular line from the origin to the geometric center as the Z-axis; and the direction of the Y-axis is not limited, as long as it is a plane perpendicular to the X-axis and Z-axis.

[0090] The coordinates of the geometric center point and the coordinates of the sampling point are determined based on the length of the vertical line and the distance between the sampling point and the foot of the vertical line. The length of the vertical line can be measured by a height sensor pre-installed in the head of the lamp, a length sensor installed in the lamp post to measure the length of the lamp post, or other methods that can measure the length of the vertical line.

[0091] The coordinates of each light-emitting subunit are determined based on the coordinates of the geometric center point and the relative positional relationship between each light-emitting subunit;

[0092] The propagation distance between each luminescent subunit and the sampling point is determined based on the coordinates of each luminescent subunit and the coordinates of the sampling point.

[0093] Based on the propagation distance and propagation loss calculation model, the transmission loss is obtained;

[0094] Based on the beam angle, transmission loss, and target brightness range, establish an expression for the light intensity of all emitting sub-units at this sampling point;

[0095] Select n sampling points to obtain their corresponding light intensity expressions, and combine the light intensity expressions to form a system of n equations.

[0096] Furthermore, those skilled in the art will understand that the beam angle is defined as follows: In the light source intensity distribution curve (light distribution curve), when the light intensity drops to "50% of the maximum central light intensity," the angle between the two corresponding directions corresponds to the beam angle. The relationship between the beam angle and the light intensity (unit: candela cd) satisfies the cosine law, that is, the light intensity in a certain direction is proportional to the cosine value of the angle between that direction and the optical axis of the light-emitting subunit—the smaller the beam angle, the higher the central light intensity; the larger the beam angle, the lower the central light intensity. The specific setting of the cosine function is related to the factory parameters of the LED desk lamp, is independent of other factors, and can be directly measured. Based on this, by combining transmission loss, target brightness range, and the principle of light superposition, a system of equations containing n unknowns and n equations is established and solved simultaneously to obtain the value of each unknown (i.e., the initial light intensity in the embodiments of this invention).

[0097] This invention provides a calculation process for solving simultaneous equations:

[0098] The geometric center of each light-emitting sub-unit is determined based on its spatial arrangement. A perpendicular line is drawn from the geometric center to the working plane, with the foot of the perpendicular as the origin. A three-dimensional rectangular coordinate system is established with the foot of the perpendicular as the origin, including: selecting the point farthest from the foot of the perpendicular within the effective lighting range and marking the direction of the line connecting it to the foot of the perpendicular as the X-axis; the direction of the line connecting the origin and the geometric center as the Z-axis; and the Y-axis direction originating from the origin and perpendicular to the X-axis and Y-axis planes. It can be understood that the effective lighting range, selecting the point farthest from the foot of the perpendicular and marking the direction of the line connecting it to the foot of the perpendicular, and the major axis of the ellipse, are all on a straight line. In implementation, the first and second working ranges of both hands are determined separately. The union of the first and second working ranges is used to determine the user's working range. It can be understood that the effective lighting range of the LED desk lamp on the working plane is elliptical, with the two endpoints of the working range being the two ends of the major axis of the ellipse, and the distances between the two ends and the desk lamp are known based on the three-dimensional model of the hand and the principle of linear perspective. In a two-dimensional rectangular coordinate system formed by the X and Y axes, the distance between the two endpoints is the major axis *a* of the ellipse, and the midpoint of the major axis is the center of the ellipse (x0, y0). Therefore, combining the ellipse formula: The formula contains only three unknowns: x, y, and b. Substituting the coordinates of any vertex of the minor axis yields the value of b (the coordinates of the minor axis vertex are obtained by acquiring the center point coordinates and the image of the effective illumination range, and calculating the actual length of the minor axis based on its length in the image and the principle of linear perspective). Choose any n sampling points within the ellipse (i.e., satisfying...). (n sampling points); convert the coordinates of the n sampling points from a two-dimensional Cartesian coordinate system to a three-dimensional Cartesian coordinate system. In the three-dimensional Cartesian coordinate system, the coordinates of the center point and the coordinates between each sampling point are known quantities, which can be used to calculate and determine the propagation distance between each emitting subunit and the sampling point. The calculation process of finding the distance between two points given their coordinates and the angle between the lines connecting each point are existing technologies and will not be elaborated here. Based on the propagation distance and the propagation loss calculation model, the transmission loss is obtained.

[0099] Based on the principle of brightness superposition at sampling point n1, an expression for the light intensity of each luminous subunit at sampling point n1 is established: f(n1) = light intensity corresponding to the target brightness range; the initial light intensity of each luminous subunit is set to F1, F2, F3...F n By combining the formulas for beam angle, propagation distance, and propagation loss, the actual light intensity of each emitting subunit at sampling point n1 can be calculated as αF1, βF2, γF3...δF. n (Where, the coefficients α, β, γ...δ can be calculated using the formulas for beam angle, propagation distance, and propagation loss.) For the remaining sampling points, establish the sampling points n1~n for each luminescent subunit. n The superposition formula for the brightness at a given location is used, and the system of equations is solved simultaneously. The system contains only n unknowns, namely F1, F2, F3...F... n This can be solved; the solution for each luminescent subunit at sampling points n1~n n The actual light intensities at the points are αF1, βF2, γF3...δF. n This allows us to determine the initial luminescence intensity of each luminescent subunit.

[0100] Furthermore, the effective light spot area is defined as: the smallest light spot area formed by the LED desk lamp on the working plane that covers the effective lighting range;

[0101] The effective plane is the plane (such as the desktop) where the effective light spot area formed by the LED desk lamp illumination is located.

[0102] Furthermore, the beam angle is: in the light intensity distribution curve of the light source, when the light intensity drops to 50% of the maximum light intensity at the center, the angle between the two directions corresponds to the light intensity gradually decreasing as the angle between the light direction and the center line direction gradually increases. This is the existing technology, and the size of the beam angle is determined in production, so it will not be elaborated here.

[0103] Furthermore, the target brightness range of the desk lamp is determined based on the ambient brightness, specifically including:

[0104] A mapping table between preset ambient brightness and target brightness ranges is constructed based on experimental data on human visual comfort, and includes the optimal target brightness range corresponding to different ambient brightness ranges.

[0105] The ambient brightness is compared with different ambient brightness ranges to determine the corresponding ambient brightness range;

[0106] Based on the preset mapping table between ambient brightness and target brightness range, the optimal target brightness range corresponding to the corresponding ambient brightness range is determined as the target brightness range of the desk lamp.

[0107] It is understandable that experimental data on human visual comfort can be obtained through experiments, existing relevant regulations, or other means, and the data obtained is sufficient to reduce human fatigue and increase human eye comfort.

[0108] Please see Figure 2 As shown, it is a structural block diagram of the LED desk lamp adaptive control system according to an embodiment of the present invention, including:

[0109] Modeling unit, used to create a hand model for recognizing hand posture and size;

[0110] A brightness determination unit is used to respond to the desk lamp start signal, acquire the ambient brightness, and determine the target brightness range of the desk lamp based on the ambient brightness.

[0111] The range determination unit is used to acquire images of the user's hand and determine the effective lighting range of the desk lamp based on the hand model and the hand images.

[0112] The area determination unit is used to determine the effective light spot area based on the effective lighting range, the spatial position of the table lamp, and the relative positional relationship of the plane of action.

[0113] The sampling unit is used to select the farthest point and the nearest point to the desk lamp within the effective light spot area and connect them, and select n sampling points on the connection line;

[0114] The computation unit is used to establish a set of n equations about the initial light intensity of each light-emitting sub-unit for a single sampling point, based on the beam angle between the sampling point and each light-emitting sub-unit, the propagation distance between each light-emitting sub-unit and the sampling point, and the propagation loss calculation model; and solve the set of n equations corresponding to all sampling points to obtain the initial light intensity of each light-emitting sub-unit.

[0115] The correction unit is used to correct the PWM conduction time ratio of each light-emitting sub-unit according to the initial light intensity.

[0116] Furthermore, an LED desk lamp includes: a lamp body, an LED desk lamp assembly, a sensor, a processor, a driver circuit, and a power supply.

[0117] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. An adaptive control method for an LED desk lamp, characterized in that, include: Establish a hand model for recognizing hand posture and size; In response to the desk lamp start signal, the ambient brightness is acquired, and the target brightness range of the desk lamp is determined based on the ambient brightness. Collect images of the user's hand, and determine the effective lighting range of the desk lamp based on the hand model and the hand images; The effective light spot area is determined based on the effective lighting range, the spatial position of the table lamp, and the relative positional relationship of the plane of action. Randomly select n sampling points within the effective light spot area; For a single sampling point, based on the beam angle between the sampling point and each light-emitting sub-unit, the propagation distance between each light-emitting sub-unit and the sampling point, and the propagation loss calculation model, an n-variable equation system is established regarding the initial light intensity of each light-emitting sub-unit. By solving the system of n equations corresponding to all sampling points, the initial light intensity of each luminous subunit can be obtained. The PWM conduction time ratio of each light-emitting sub-unit is corrected based on the initial light intensity; The process of acquiring a user's hand image and determining the effective illumination range of the desk lamp based on the hand model and the hand image includes: In response to a switch trigger signal, acquire a hand image and record it as the initial hand image; Based on the initial hand image and the principle of linear perspective, the actual hand size parameters are calculated and obtained. Input the actual hand size parameters into the hand model to generate a three-dimensional model of the user's hand; Continuously collect images of the user's hands, filter out the smallest and largest hand images, and record them as boundary hand images respectively; Identify the hand pose in the boundary hand image, input the hand pose into the hand 3D model, and output the hand pose 3D model corresponding to the hand pose; Based on the aforementioned three-dimensional model of hand posture and the principle of linear perspective, the distance range of hand movement is calculated, and the effective lighting range is determined according to the distance range of hand movement.

2. The adaptive control method for an LED desk lamp according to claim 1, characterized in that, The hand model is constructed based on ergonomic data. When the actual size parameters of the hand are input, the corresponding three-dimensional hand model is output. When combined with a hand image as input, the output is a 3D model of the hand pose corresponding to the hand pose in the hand image.

3. The adaptive control method for an LED desk lamp according to claim 1, characterized in that, The propagation loss calculation model is built based on the relationship between light loss and propagation distance during light propagation in the air as input data. If the propagation distance is input, the transmission loss is output.

4. The adaptive control method for an LED desk lamp according to claim 3, characterized in that, The method, based on the beam angle between the sampling point and each emitting sub-unit, the propagation distance between each emitting sub-unit and the sampling point, and the propagation loss calculation model, establishes a set of n equations regarding the initial light intensity of each emitting sub-unit, including: Obtain the geometric center point of all light-emitting sub-units, and draw a perpendicular line from the geometric center point to the plane of action to determine the foot of the perpendicular; A three-dimensional rectangular coordinate system is established with the foot of the perpendicular as the origin, wherein: the point farthest from the foot of the perpendicular is selected in the effective lighting range and the direction of the line connecting it to the foot of the perpendicular is recorded as the X-axis; the direction of the line connecting the origin and the geometric center point is recorded as the Z-axis; and the Y-axis direction starts from the origin and is perpendicular to the X-axis and Y-axis planes. The coordinates of the geometric center point and the coordinates of the sampling point are determined based on the length of the perpendicular line and the distance between the sampling point and the foot of the perpendicular. The coordinates of each light-emitting subunit are determined based on the coordinates of the geometric center point and the relative positional relationship between each light-emitting subunit; The propagation distance between each light-emitting sub-unit and the sampling point is determined based on the coordinates of each light-emitting sub-unit and the coordinates of the sampling point. Based on the propagation distance and the propagation loss calculation model, the transmission loss is obtained; Based on the beam angle, the transmission loss, and the target brightness range, establish an expression for the light intensity of all light-emitting subunits at this sampling point; Within the effective illumination range, arbitrarily select n sampling points to obtain their corresponding light intensity expressions, and then combine the light intensity expressions to form a system of n equations.

5. The adaptive control method for an LED desk lamp according to claim 1, characterized in that, The effective light spot area is: the smallest light spot area formed by the LED desk lamp on the working plane that covers the effective lighting range; The plane of action is the plane in which the effective light spot area formed by the LED desk lamp illumination is located.

6. The adaptive control method for an LED desk lamp according to claim 1, characterized in that, The beam angle is the angle between two directions when the luminous intensity drops to 50% of the maximum luminous intensity at the center in the light source intensity distribution curve.

7. The adaptive control method for an LED desk lamp according to claim 1, characterized in that, The step of determining the target brightness range of the desk lamp based on the ambient brightness specifically includes: A mapping table between preset ambient brightness and target brightness ranges is provided. The mapping table is constructed based on human visual comfort experimental data and includes the optimal target brightness range corresponding to different ambient brightness ranges. The ambient brightness is compared with different ambient brightness ranges to determine the corresponding ambient brightness range; Based on the preset mapping table between ambient brightness and target brightness range, the optimal target brightness range corresponding to the corresponding ambient brightness range is determined as the target brightness range of the desk lamp.

8. An adaptive control system for an LED desk lamp, used to implement the adaptive control method for an LED desk lamp according to any one of claims 1-7, characterized in that, include: Modeling unit, used to create a hand model for recognizing hand posture and size; A brightness determination unit is used to respond to a desk lamp start signal, acquire ambient brightness, and determine the target brightness range of the desk lamp based on the ambient brightness. The range determination unit is used to acquire images of the user's hand and determine the effective lighting range of the desk lamp based on the hand model and the hand images; The area determination unit is used to determine the effective light spot area based on the effective lighting range, the spatial position of the table lamp, and the relative positional relationship of the plane of action. A sampling unit is used to select the farthest point and the nearest point to the desk lamp within the effective light spot area and connect them, and select n sampling points on the connecting line. The computation unit is used to establish a set of n equations about the initial light intensity of each light-emitting sub-unit for a single sampling point, based on the beam angle between the sampling point and each light-emitting sub-unit, the propagation distance between each light-emitting sub-unit and the sampling point, and the propagation loss calculation model; and solve the set of n equations corresponding to all sampling points to obtain the initial light intensity of each light-emitting sub-unit. The correction unit is used to correct the PWM conduction time ratio of each light-emitting sub-unit according to the initial light intensity.

9. An LED desk lamp for implementing the adaptive control method for an LED desk lamp according to any one of claims 1-7, characterized in that, include: The lamp body, LED desk lamp assembly, sensor, processor, driver circuit, and power supply.

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