LED fluorescent screen and control method thereof

Abstract

The invention discloses an LED fluorescent screen and a control method thereof, and the LED fluorescent screen comprises a power supply, a light guide panel, a plurality of illumination units, a light diffusion plate and a control assembly. Each lighting unit comprises a visible spectrum sensor and at least one first lamp bead, and each first lamp bead is at least provided with light sources of three colors of R, G and B. When a user smears a fluorescent material on the fluorescent panel, the fluorescent material emits light of different colors under irradiation of light rays scattered by the light scattering plate, the visible spectrum sensor measures spectrum information of the light rays emitted by the fluorescent material in the corresponding area and transmits the spectrum information to the control assembly, and the control assembly controls the control assembly to work. The control assembly controls the R, G and B three-color light sources of the first lamp beads to change the light emitting intensity according to the spectral information, and then the color of scattered light rays scattered by the light scattering plate in the corresponding irradiation area is changed, so that the color of the light scattering plate and the color of the fluorescent material in the corresponding area form contrast, and the purpose of highlighting the fluorescent material is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of LED fluorescent panels, and in particular to an LED fluorescent panel and a control method thereof. Background Art

[0002] LED fluorescent board is a commonly used luminous advertising board. Its principle is to use the scattering ability of fluorescent materials to achieve the effect of luminescence. At present, the commonly used LED fluorescent boards on the market are mostly equipped with light strips around the panel. There are multiple lamp beads on the light strips. Each lamp bead has several light sources of different colors. The controller controls the power on and off of the light sources of different colors on each lamp bead to change the color of the light emitted by the lamp bead. The light emitted by the lamp bead enters from the side of the panel and transmits inside the panel. When the special fluorescent material is applied to the panel, the fluorescent material will scatter the light under the irradiation of light, showing a luminous effect. Users can use fluorescent materials of various colors to draw any pattern on the panel according to their needs to display text or picture information.

[0003] The LED fluorescent panels currently used use a whole acrylic plate as a light-guiding panel, and the lamp beads are set around the panel. The user can only control the brightness of the entire fluorescent panel, and cannot change the brightness of a specific area alone, and cannot highlight the specified area to highlight certain information. And it is impossible to change the background color according to the color of the picture to adapt to the needs of different colors. For example, some LED fluorescent panels will have a black back panel on the back of the panel. When the user draws a dark-toned fluorescent material on the panel, the picture will not be displayed clearly enough. There are also some LED fluorescent panels that do not have a black back panel, and the entire LED fluorescent panel presents a transparent effect. When the user draws a light-toned fluorescent material on the panel, it will be the same or close to the background color, making it impossible for the text or picture information to stand out from the background.

[0004] Although some LED fluorescent panels can change the display effect of a specific area of ​​the LED fluorescent panel by controlling the brightness or color of a few specific lamp beads, due to the good light-guiding effect of the acrylic panel, the light emitted by the lamp beads will propagate throughout the entire panel, causing the display effect of the entire panel to change due to these lamp beads, and the differentiated display effect in a specific area is not ideal. Summary of the invention

[0005] In order to solve the technical problem of displaying different areas differently on an LED fluorescent panel, the present application provides an LED fluorescent panel and a control method thereof.

[0006] The LED fluorescent panel includes: a power supply, a light guide panel, a plurality of lighting units, a diffuser plate and a control component. The plurality of lighting units are arranged side by side, each of the lighting units includes a visible spectrum sensor and at least one first lamp bead, each of the first lamp bead has at least three light sources of R, G and B colors, the visible spectrum sensor is used to measure the spectrum information of the light emitted by the fluorescent material in the corresponding area on the light guide panel, and transmit the spectrum information to the control component. The diffuser plate is arranged in parallel between the light guide panel and the lighting unit, and the diffuser plate is used to scatter the light emitted by the first lamp bead. The light guide panel is made of light guide material, and the light guide panel is used to apply fluorescent material, and the control component is used to control the first lamp bead according to the spectrum information.

[0007] When the user applies fluorescent material on the fluorescent panel, the fluorescent material emits light of different colors under the irradiation of the light scattered by the diffuser plate. The visible spectrum sensor measures the spectral information of the light emitted by the fluorescent material in the corresponding area, and transmits the spectral information to the control component. The control component changes the intensity of the light emitted by the three colors of R, G, and B of the first lamp bead according to the spectral information, and then changes the color of the light scattered by the diffuser plate in the corresponding irradiation area, so that the color of the diffuser plate forms a contrast with the color of the fluorescent material in the corresponding area, thereby achieving the purpose of highlighting the fluorescent material.

[0008] Specifically, the first lamp bead has four light sources of R, G, B, and W. In most cases, the first lamp bead can control the light source of W color to work to emit white light. White light has good color rendering and can accurately reflect the color of the fluorescent material itself.

[0009] Specifically, the light guide panel adopts a four-wire resistive touch control panel. When the user applies fluorescent material on the light guide panel, the light guide panel can transmit the coordinate information of the touched area to the control component. After receiving the coordinate information, the control component controls the lighting unit of the corresponding area to be powered on, and the first lamp bead illuminates the corresponding area. The first lamp bead corresponding to the area without applying fluorescent material remains in a power-off state, which can not only highlight the information displayed by the fluorescent material, but also save electricity.

[0010] Furthermore, the LED fluorescent panel also includes at least one lighting strip, on which a plurality of second lamp beads are arranged, and the lighting strip is arranged on the side of the light guide panel, so that the light emitted by the second lamp beads is irradiated into the light guide panel from the side. The second lamp beads are used as the main light source to illuminate the fluorescent material, and the first lamp beads are used as the background light source only to change the color of the diffuser plate, which can reduce the color deviation of the fluorescent material and improve the color rendering effect.

[0011] Furthermore, the lighting unit further comprises a Fresnel lens, the Fresnel lens having a plane and a threaded surface, the Fresnel lens being arranged in parallel between the photosensitive element of the visible spectrum sensor and the light guide panel, the plane of the Fresnel lens being close to the photosensitive element, and the threaded surface being close to the light guide panel. The Fresnel lens can focus light incident at a large angle, or scatter the incident light into parallel light, which can well increase the light intensity irradiated on the photosensitive element, thereby increasing the sensitivity and observation angle of the visible spectrum sensor, thereby reducing the distance between the visible spectrum sensor and the light guide panel, making the arrangement of the LED fluorescent panel more compact, and reducing the volume of the LED fluorescent panel.

[0012] Furthermore, the diffuser plate has a plurality of diffuser areas of the same shape and size as the lighting unit, and an opaque partition layer is provided between each diffuser area, and the partition layer is used to block the propagation of light. The lighting unit can only illuminate the corresponding diffuser area, so that the light of adjacent diffuser areas will not affect each other, thereby increasing the color difference between each diffuser area, and making the contrast between the color of the diffuser plate and the color of the fluorescent material more obvious.

[0013] Furthermore, the LED fluorescent panel also includes a bottom plate and a frame, and the bottom plate and the frame cooperate to form a space for accommodating the power supply, the light guide panel, all the lighting units, the diffuser plate and the control component.

[0014] The present application also provides a control method for controlling the above-mentioned LED fluorescent panel, comprising the following steps: S1. Obtaining spectrum information of light emitted by the fluorescent material in the corresponding area on the light guide panel, and obtaining light intensity values ​​corresponding to the three colors R, G, and B respectively; S2, calculating the sum of the light intensity values ​​corresponding to the three colors R, G, and B in the spectrum information; S3, respectively calculating the ratio of the light intensity values ​​of the three colors R, G, and B to the sum of the light intensity values; S4, respectively calculate the absolute difference between the ratio of the three colors R, G, and B and 1; S5. Control the light source of the first lamp bead to emit light according to the absolute difference between the three colors R, G, and B and 1.

[0015] The synthesis of visible light colors complies with the principle of additive color mixing and is linearly added. Therefore, after obtaining the spectral information of the light emitted by the fluorescent material, the proportions of the three colors R, G, and B are reversed to obtain a color with a greater contrast with the color of the fluorescent material.

[0016] Specifically, in step S5, the absolute difference between the three colors R, G, and B and 1 is used as the duty cycle of the light sources of the three colors R, G, and B to control the operation of the light sources of the three colors. PMW dimming technology is a commonly used control method for adjusting the brightness or color of LED lamp beads. Its principle is to change the brightness by controlling the duty cycle of the LED lamp beads, that is, the LED is quickly turned on and off under the control of the pulse current, and the brightness of the LED lamp is changed by changing the ratio of the power-off time to the power-on time of the LED lamp. For multi-color lamp beads, the color of the multi-color lamp beads is changed by changing the duty cycle of the light sources of different colors. The advantage of this method is that it can effectively reduce the energy consumption of LED lamps.

[0017] Specifically, in step S5, the absolute difference between the three colors R, G, and B and 1 is multiplied by the rated current of the three light sources to obtain the target current values ​​corresponding to the three color light sources of R, G, and B, and control the operation of the three color light sources. Analog dimming technology is also a commonly used LED lamp dimming technology. It changes the brightness of the LED lamp beads by changing the current of the LED lamp beads, and also has the advantage of energy saving.

[0018] Technical effects and advantages of the present invention: By setting up a visible spectrum sensor, the spectral information of the light emitted by the fluorescent material in the corresponding area can be measured, and the spectral information can be transmitted to the control component. The control component controls the three color light sources of R, G, and B of the first lamp bead to change the intensity of the light emission according to the spectral information, and then changes the color of the light scattered by the diffuser plate in the corresponding irradiation area, so that the color of the diffuser plate forms a contrast with the color of the fluorescent material in the corresponding area, thereby achieving the purpose of highlighting the fluorescent material. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic diagram of the decomposition of the LED fluorescent panel provided in the first embodiment of the present invention.

[0020] Figure 2 This is a schematic diagram of the decomposition of the LED fluorescent panel provided in the second embodiment of the present invention.

[0021] Figure 3 It is a schematic diagram of the structure of the lighting unit in the second embodiment of the present invention.

[0022] The figures are marked as follows: 1. lighting unit; 11. visible spectrum sensor; 111. photosensitive element; 12. first lamp bead; 13. Fresnel lens; 131. plane; 132. threaded surface; 2. diffuser plate; 21. diffuser area; 22. partition layer; 3. light guide panel; 4. control component; 5. lighting strip; 51. second lamp bead; 6. bottom plate; 7. frame. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] Embodiment 1 refer to Figure 1 The first embodiment of the present invention provides an LED fluorescent panel, including a power supply, a plurality of lighting units 1, a diffuser plate 2, a light guide panel 3 and a control component 4. The plurality of lighting units 1 are arranged side by side, each lighting unit 1 includes a visible spectrum sensor 11 and at least one first lamp bead 12, each first lamp bead 12 has at least three light sources of R, G, and B colors, and the visible spectrum sensor 11 is used to measure the spectrum information of the light emitted by the fluorescent material in the corresponding area on the light guide panel 3, and transmit the spectrum information to the control component 4. The diffuser plate 2 is arranged in parallel between the light guide panel 3 and the lighting unit 1, and the diffuser plate 2 is used to scatter the light emitted by the first lamp bead 12. The light guide panel 3 is made of light guide material, and the light guide panel 3 is used to apply the fluorescent material, and the control component 4 is used to control the first lamp bead 12 according to the spectrum information.

[0025] When the user applies fluorescent material on the fluorescent panel, the fluorescent material emits light of different colors under the irradiation of the light scattered by the diffuser plate 2. The visible spectrum sensor 11 measures the spectral information of the light emitted by the fluorescent material in the corresponding area, and transmits the spectral information to the control component 4. The control component 4 changes the intensity of the light emitted by the three colors of R, G, and B of the first lamp bead 12 according to the spectral information, and then changes the color of the light scattered by the diffuser plate 2 in the corresponding irradiation area, so that the color of the diffuser plate 2 forms a contrast with the color of the fluorescent material in the corresponding area, thereby achieving the purpose of highlighting the fluorescent material.

[0026] Figure 1 The LED fluorescent panel shown uses 35 lighting units to form a 5*7 array, and each lighting unit is provided with a first lamp bead 12, and the first lamp bead 12 has four color light sources of R, G, B, and W. In most cases, the first lamp bead 12 can control the light source of color W to emit white light. White light has good color rendering and can accurately reflect the color of the fluorescent material itself. In the process of actual application, the more lighting units are set, the more it can adapt to the more complex color changes of fluorescent materials, and the better the display effect.

[0027] There are many mature products of visible spectrum sensor 11, such as AS7341 visible spectrum sensor, which has eight visible light channels and can detect the light intensity data of visible light in eight bands. And this type of sensor has mature technology and low price, and has been widely used.

[0028] Of course, in actual use, the user can also turn off the automatic dimming function of the lighting unit 1, so that the lighting unit 1 emits light in a fixed color, thereby keeping the background color of the entire LED fluorescent board uniform and can be used with different picture styles.

[0029] Specifically, the light guide panel 3 adopts a four-wire resistive touch control panel. When the user applies fluorescent material on the light guide panel 3, the light guide panel 3 can transmit the coordinate information of the touched area to the control component 4. After receiving the coordinate information, the control component 4 controls the lighting unit 1 of the corresponding area to be powered on, and the first lamp bead 12 illuminates the corresponding area. The first lamp bead 12 corresponding to the area where the fluorescent material is not applied remains in the off state, which can not only highlight the information displayed by the fluorescent material, but also save electricity. The four-wire resistive touch control board is a very mature product, which is mostly used in industrial display controllers and combined with liquid crystal display screens to achieve the purpose of display and interactive control. It is low-priced and widely used.

[0030] Embodiment 2 Figure 2 and Figure 3 The second embodiment of the present application is shown. Based on the first embodiment, the LED fluorescent panel also includes at least one lighting strip 5, on which a plurality of second lamp beads 51 are arranged. The lighting strip 5 is arranged on the side of the light guide panel 3, so that the light emitted by the second lamp beads 51 is irradiated into the light guide panel 3 from the side.

[0031] Since the fluorescent material emits light by scattering the light of the first lamp bead 12, when the first lamp bead 12 is used as the main light source, after adjusting the color of the first lamp bead 12 according to the light emitted by the fluorescent material, the light emitted by the fluorescent material will deviate from the original color of the fluorescent material, affecting the final display effect. Therefore, the second lamp bead 51 is used as the main light source to illuminate the fluorescent material, and the first lamp bead 12 is used as the background light source only to change the color of the diffuser plate 2, which can reduce the color deviation of the fluorescent material and improve the color rendering effect.

[0032] Furthermore, the lighting unit 1 further comprises a Fresnel lens 13, the Fresnel lens 13 having a plane 131 and a threaded surface 132, the Fresnel lens 13 being arranged parallel between the photosensitive element 111 of the visible spectrum sensor 11 and the light guide panel 3, the plane 131 of the Fresnel lens 13 being close to the photosensitive element 111, and the threaded surface 132 being close to the light guide panel 3. The Fresnel lens 13 can focus light incident at a large angle, or scatter the incident light into parallel light, which can well improve the light intensity irradiated on the photosensitive element 111, thereby improving the sensitivity and observation angle of the visible spectrum sensor 11, thereby reducing the distance between the visible spectrum sensor 11 and the light guide panel 3, making the arrangement of the LED fluorescent panel more compact, and reducing the volume of the LED fluorescent panel.

[0033] Furthermore, the diffuser plate 2 has a plurality of diffuser regions 21 of the same shape and size as the lighting unit 1, and an opaque partition layer 22 is provided between each diffuser region 21, and the partition layer 22 is used to block the propagation of light. When the diffuser plate 2 is made of a whole plate, the light emitted by adjacent lighting units 1 will affect each other, thereby affecting the color actually displayed by the diffuser plate 2. By dividing the diffuser plate 2 into a plurality of independent diffuser regions 21, the lighting unit 1 can only illuminate the corresponding diffuser regions 21, so that the light of adjacent diffuser regions 21 will not affect each other, thereby increasing the color difference between each diffuser region 21, and making the contrast between the color of the diffuser plate 2 and the color of the fluorescent material more obvious.

[0034] Furthermore, the LED fluorescent panel also includes a bottom plate 6 and a frame 7 , and the bottom plate 6 and the frame 7 cooperate to form a space for accommodating a power source, a light guide panel 3 , all lighting units 1 , a diffuser plate 2 and a control component 4 .

[0035] Embodiment 3 The third embodiment of the present application provides a control method for controlling the above-mentioned LED fluorescent panel, comprising the following steps: S1. Obtaining spectrum information of light emitted by the fluorescent material in the corresponding area on the light guide panel, and obtaining light intensity values ​​corresponding to the three colors R, G, and B respectively; S2, calculating the sum of the light intensity values ​​corresponding to the three colors R, G, and B in the spectrum information; S3, respectively calculating the ratio of the light intensity values ​​of the three colors R, G, and B to the sum of the light intensity values; S4, respectively calculate the absolute difference between the ratio of the three colors R, G, and B and 1; S5. Control the light source of the first lamp bead to emit light according to the absolute difference between the three colors R, G, and B and 1.

[0036] The synthesis of visible light colors complies with the principle of additive color mixing and is linearly added. Therefore, after obtaining the spectral information of the light emitted by the fluorescent material, the proportions of the three colors R, G, and B are reversed to obtain a color with a greater contrast with the color of the fluorescent material.

[0037] Specifically, in step S5, there are multiple ways to control the light source of the first lamp bead, that is, a PMW (pulse width modulation) dimming method or an analog dimming method can be used, and both have their advantages and disadvantages. The PMW dimming method is more efficient and has a wide brightness adjustment range, but when the duty cycle of the light source is relatively low, a flickering effect will occur, affecting the lighting effect. The advantage of the analog dimming method is that there will be no flickering effect, but the brightness adjustment range is limited, and the adjustment efficiency is low. When the current of the light source is small, the color will deviate. In the specific application process, different control methods can be selected according to actual needs.

[0038] When the PMW dimming method is used, the absolute difference between the three colors R, G, and B and 1 is used as the duty cycle of the three colors of light sources to control the operation of the three colors of light sources. PMW dimming technology is a commonly used control method for adjusting the brightness or color of LED lamp beads. Its principle is to change the brightness by controlling the duty cycle of LED lamp beads, that is, the LED is quickly turned on and off under the control of pulse current, and the brightness of the LED lamp is changed by changing the ratio of the power-off time to the power-on time of the LED lamp. For multi-color lamp beads, the color of the multi-color lamp beads is changed by changing the duty cycle of light sources of different colors. The advantage of this method is that it can effectively reduce the energy consumption of LED lamps.

[0039] When using the analog dimming method, the absolute difference between the three colors R, G, and B and 1 is multiplied by the rated current of the three light sources to obtain the target current values ​​corresponding to the three light sources of R, G, and B, and control the operation of the three light sources. Analog dimming technology is also a commonly used LED lamp dimming technology. It changes the brightness of the LED lamp beads by changing the current of the LED lamp beads, and also has the advantage of energy saving.

[0040] Finally: The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An LED fluorescent panel, characterized in that: include: A power supply, a light guide panel, a plurality of lighting units, a diffuser, and a control assembly; A plurality of the lighting units are arranged side by side, each of the lighting units comprises a visible spectrum sensor and at least one first lamp bead, each of the first lamp bead has at least three light sources of R, G, and B colors, and the visible spectrum sensor is used to measure the spectrum information of the light emitted by the fluorescent material in the corresponding area on the light guide panel, and transmit the spectrum information to the control component; The light diffuser is arranged in parallel between the light guide panel and the lighting unit, and is used to diffuse the light emitted by the first lamp bead; The light guide panel is made of light guide material, and the light guide panel is used to apply fluorescent material; The control component is used to control the first lamp bead according to the spectrum information.

2. The LED fluorescent plate according to claim 1, characterized in that: The first lamp bead has light sources of four colors: R, G, B, and W.

3. The LED fluorescent plate according to claim 1, characterized in that: The light guide panel adopts a four-wire resistive touch control panel.

4. The LED fluorescent plate according to claim 1, characterized in that: The LED fluorescent panel also includes at least one lighting strip, on which a plurality of second lamp beads are arranged. The lighting strip is arranged on the side of the light guide panel so that the light emitted by the second lamp beads is irradiated into the light guide panel from the side.

5. The LED fluorescent plate according to claim 1, characterized in that: The lighting unit further comprises a Fresnel lens having a plane and a threaded surface. The Fresnel lens is arranged in parallel between the photosensitive element of the visible spectrum sensor and the light guide panel. The plane of the Fresnel lens is close to the photosensitive element, and the threaded surface is close to the light guide panel.

6. The LED fluorescent plate according to claim 1, characterized in that: The light diffusion plate has a plurality of light diffusion areas with the same shape and size as the lighting unit, and an opaque partition layer is arranged between each of the light diffusion areas, and the partition layer is used to block the propagation of light.

7. The LED fluorescent panel according to claim 1, characterized in that: The LED fluorescent panel also includes a bottom plate and a frame. The bottom plate and the frame cooperate to form a space for accommodating the power supply, the light guide panel, all the lighting units, the light diffusion plate and the control component.

8. A method for controlling an LED fluorescent panel, used for controlling the LED fluorescent panel according to claim 1, characterized in that: The following steps are involved: S1. Obtaining spectrum information of light emitted by the fluorescent material in the corresponding area on the light guide panel, and obtaining light intensity values ​​corresponding to the three colors R, G, and B respectively; S2, calculate the sum of the light intensity values ​​corresponding to the three colors R, G, and B in the spectrum information; S3, respectively calculating the ratio of the light intensity values ​​of the three colors R, G, and B to the sum of the light intensity values; S4, respectively calculate the absolute difference between the ratio of the three colors R, G, and B and 1; S5. Control the light source of the first lamp bead to emit light according to the absolute difference between the three colors R, G, and B and 1.

9. The control method according to claim 8, characterized in that: In step S5, the absolute differences between the three colors R, G, B and 1 are used as the duty cycles of the light sources of the three colors R, G, B to control the operation of the light sources of the three colors.

10. The control method according to claim 8, characterized in that: In step S5, the absolute differences between the three colors R, G, and B and 1 are multiplied by the rated currents of the three light sources to obtain the target current values ​​corresponding to the three color light sources, and the three color light sources are controlled to work.

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