LED module and display screen

Abstract

The utility model provides a light-emitting diode (LED) module and a display screen. The LED module comprises a printed circuit board (PCB) base layer; the LED circuit layer is arranged above the PCB base layer; the LED lamp bead layer is arranged above the LED circuit layer and is electrically connected with the LED circuit layer; the heating layer is arranged between the PCB base layer and the LED circuit layer, and the heating layer is of an annular structure arranged on the edge of the PCB base layer in a surrounding mode. Through the technical scheme provided by the invention, the problem of poor display effect caused by temperature difference between the middle and the periphery of a display screen in the related technology can be solved.

Description

TECHNICAL FIELD

[0001] The utility model relates to display device technical field, specifically, relate to a kind of LED module and display screen. BACKGROUND

[0002] At present, in the direct display type LED display industry, the way of LED module splicing into display screen is that most of them are fixed on module support or box, and then connected into screen by connecting sheet etc.. At the same time, considering the weather resistance, reliability (such as structural strength, etc.), thermal conductivity and EMC (Electro Magnetic Compatibility) requirements, metal material is mostly used to make box or module support, which can provide good heat conduction environment for LED module and make LED module display for a long time with high quality.

[0003] However, the utility model person found that when fixing the LED module, the periphery of the LED module will cover copper edge, so as to be connected with the metal box / module support to realize grounding conduction. This will derive the problem that the periphery of the LED module is in contact with the box through metal, forming heat conduction, so that the heat of the light emitting unit is transmitted to the box through the PCB substrate, and there is no contact between the middle of the LED module and the box. Thus, only the periphery of the LED module forms a good heat conduction area, while the middle part is still normal heat dissipation. After the screen is lit for a long time, the middle and periphery of the display screen produce temperature difference, which will cause the middle of the display screen to display white (for example, white), while the color around is cyan (relatively cold color), and the whole screen will appear a block of segmented color area, which greatly affects the visual effect.

[0004] Therefore, there is a problem in the related art that the middle and periphery of the display screen have temperature difference, which leads to poor display effect. UTILITY MODEL CONTENT

[0005] The utility model provides a kind of LED module and display screen to solve the problem of temperature difference between the middle and periphery of the display screen in the related art, which leads to poor display effect.

[0006] According to one aspect of the utility model, an LED module is provided, which includes: a PCB base layer; an LED circuit layer disposed above the PCB base layer; an LED lamp bead layer disposed above the LED circuit layer and electrically connected to the LED circuit layer; and a heating layer disposed between the PCB base layer and the LED circuit layer, the heating layer being an annular structure surrounding the edge of the PCB base layer.

[0007] Further, the LED module further comprises a first insulating layer and a second insulating layer, the heating layer is sandwiched between the first insulating layer and the second insulating layer, the upper surface of the heating layer is attached to the lower surface of the first insulating layer, and the lower surface of the heating layer is attached to the upper surface of the second insulating layer.

[0008] Further, the thickness of the heating layer is between 0.05mm and 0.08mm.

[0009] Further, the width of the heating layer is between 3mm and 4mm.

[0010] Further, the heating layer is made of nickel-chromium alloy.

[0011] Further, the PCB base layer comprises a power supply circuit layer capable of connecting a power supply, and the heating layer is electrically connected to the power supply circuit layer.

[0012] Further, the LED module further comprises a controller, and a first temperature sensor and a second temperature sensor electrically connected to the controller, the first temperature sensor is used to detect the temperature of the part of the heating layer of the LED module, the second temperature sensor is used to detect the temperature of the remaining part of the LED module, and the controller controls the working of the heating layer according to the temperature information of the first temperature sensor and the second temperature sensor.

[0013] Further, the controller has a clock circuit, and the controller acquires the temperature information of the first temperature sensor and the second temperature sensor by using the clock circuit.

[0014] According to another aspect of the present application, a display screen is provided, the display screen comprises a box body and an LED module arranged on the box body, and the LED module is the LED module provided above.

[0015] Further, the width of the heating layer of the LED module is equal to the size of the part of the edge of the LED module that overlaps with the box body.

[0016] The technical scheme of the utility model discloses, the LED module includes PCB base layer, LED circuit layer, LED lamp pearl layer and heating layer. LED circuit layer sets up at the top of PCB base layer, and LED lamp pearl layer sets up at the top of LED circuit layer and is electrically connected with LED circuit layer. Although the edge of LED module and the box pass through metal contact, form the heat conduction, but because heating layer sets up between PCB base layer and LED circuit layer, when LED module works, heating layer sends out heat, so that the heat of LED lamp pearl layer is not easy to downward transmission, like this, the temperature difference of the edge of LED module and the rest part reduces even eliminates, and the color difference of LED module will have the great improvement, thereby the screen body white-blue distribution phenomenon in the related art can be eliminated, and the display effect of display screen is greatly improved. Moreover, because heating layer is the annular structure that surrounds the edge of PCB base layer, heating layer can play a role on the whole edge of PCB base layer, and the effect of heating layer preventing the heat of LED lamp pearl layer from downward transmission is better. BRIEF DESCRIPTION OF DRAWINGS

[0017] The drawings enclosed with the specification form part of the application and serve to provide further understanding of the present application, the exemplary embodiments of the present application and the description thereof serve to explain the present application and do not constitute an undue limitation on the present application. In the drawings:

[0018] Figure 1 A structure schematic view of the LED module provided by the embodiment of the present application is shown;

[0019] Figure 2 A sectional view of the LED module provided by the embodiment of the present application is shown;

[0020] Figure 3 A structure schematic view of the LED module provided by the embodiment of the present application is shown; Figure 2 A local enlarged view of A in the figure;

[0021] Figure 4 A flow chart of the control method of the LED module provided by the embodiment of the present application is shown.

[0022] Among them, the above-mentioned drawing includes the following figure marks:

[0023] 10, PCB base layer; 20, LED circuit layer; 30, LED lamp pearl layer; 40, heating layer; 50, first insulating layer; 60, second insulating layer. DETAILED DESCRIPTION

[0024] The technical solutions in the embodiments of the present application will be clearly and completely described with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The description of the at least one exemplary embodiment is merely illustrative in nature and not intended to be limiting on the present application and its applications or uses. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of the present application.

[0025] As shown in the figure, Figures 1 to 3 The present embodiment provides an LED module, which comprises a PCB base layer 10, an LED circuit layer 20, an LED lamp bead layer 30 and a heating layer 40. The LED circuit layer 20 is arranged above the PCB base layer 10, and the LED lamp bead layer 30 is arranged above the LED circuit layer 20 and electrically connected with the LED circuit layer 20. The heating layer 40 is arranged between the PCB base layer 10 and the LED circuit layer 20, and the heating layer 40 is an annular structure arranged around the edge of the PCB base layer 10.

[0026] The LED module provided by the present embodiment is used, although the edge of the LED module is in contact with the box through metal to form heat conduction, but because the heating layer 40 is arranged between the PCB base layer 10 and the LED circuit layer 20, the heating layer 40 emits heat when the LED module works, so that the heat of the LED lamp bead layer 30 is not easily transmitted downward, so that the temperature difference between the edge of the LED module and the rest is reduced or even eliminated, the color difference of the LED module is greatly improved, so that the white-green distribution phenomenon of the screen body in the related art is eliminated, and the display effect of the display screen is greatly improved. Moreover, because the heating layer 40 is an annular structure arranged around the edge of the PCB base layer 10, the heating layer 40 can play a role on the entire edge of the PCB base layer 10, and the effect of the heating layer 40 preventing the heat of the LED lamp bead layer 30 from being transmitted downward is better.

[0027] It should be noted that the heating layer 40 is an annular structure arranged around the edge of the PCB base layer 10, and the "annular structure" here includes the following two structures: first, the heating layer 40 is a continuous annular structure extending along the edge of the PCB base layer 10; second, the heating layer 40 is an intermittent annular structure extending along the edge of the PCB base layer 10, for example, the heating layer 40 comprises a plurality of heating blocks, and the plurality of heating blocks are arranged at intervals along the edge of the PCB base layer 10.

[0028] In the present embodiment, the first structure of the heating layer 40, that is, the heating layer 40 is a continuous annular structure (a track-shaped conductive layer) extending along the edge of the PCB base layer 10, so that the effect of the heating layer 40 preventing the heat of the LED lamp bead layer 30 from being transmitted downward is better.

[0029] Furthermore, the "ring structure" here is not limited to a circular ring structure; any structure with connected ends is acceptable. In this embodiment, the PCB base layer 10 is a rectangular structure, therefore the heating layer 40 is a rectangular ring structure surrounding the edge of the PCB base layer 10.

[0030] like Figure 1 and Figure 3 As shown, the LED module also includes a first insulating layer 50 and a second insulating layer 60. A heating layer 40 is sandwiched between the first insulating layer 50 and the second insulating layer 60. The upper surface of the heating layer 40 is in contact with the lower surface of the first insulating layer 50, and the lower surface of the heating layer 40 is in contact with the upper surface of the second insulating layer 60. The first insulating layer 50 and the second insulating layer 60 work together to insulate the heating layer 40, preventing it from directly contacting other layers and causing a short circuit.

[0031] It should be noted that the non-critical layers (PCB base layer, including other wiring layers, insulating layers, and ink layers, etc.) in this embodiment have been categorized. The routing and other components contained in these non-critical layers are no different from those in conventional boards, and will not be described in detail separately. The LED circuit layer 20 is the circuit design of the pad-related lines, test point lines, and ground plane or power plane-related lines (to improve signal integrity and electromagnetic compatibility) associated with the LED bead layer 30. The first insulating layer 50 and the second insulating layer 60 are no different from the insulating layers of other layers in terms of material. They are both pre-impregnated materials (a semi-solid epoxy resin material that plays a role in bonding wiring layers and filling gaps during the subsequent PCB board lamination process), and have the functions of electrical isolation of the circuit layer, overall shape support, and impedance control.

[0032] The thickness of the heating layer 40 is between 0.05mm and 0.08mm, and the width of the heating layer 40 is between 3mm and 4mm. In this way, the heating layer 40 has a good heating effect, but it is not too thick or too wide, so as to avoid interference between the heating layer 40 and the components on other layers.

[0033] Specifically, the thickness of the heating layer 40 can be 0.05mm, 0.06mm, 0.07mm, 0.08mm, or any other value between 0.05mm and 0.08mm. In this embodiment, the thickness of the heating layer 40 is 0.05mm. The width of the heating layer 40 can be 3mm, 3.5mm, 4mm, or any other value between 3mm and 4mm. In this embodiment, the width of the heating layer 40 is 3mm.

[0034] It should be noted that the width dimension of the heating layer 40 refers to the radial dimension of the heating layer 40.

[0035] In the embodiment, the heating layer 40 is made of nickel-chromium alloy, which has excellent material properties. The resistivity of the heating layer 40 is high (about 1.1*10^-6 Ω·m), and the material has excellent properties, good temperature resistance, mechanical strength and stability, and is not easy to deform at high temperature. The heating layer 40 is an excellent material for making heating wires, and the mass of the heating layer 40 is small, which does not significantly increase the mass of the module.

[0036] In order to facilitate the description of the heating layer 40, the following formula can be referred to: Joule's law shows that the product of the square of the current passing through a resistor and the resistance value is equal to the power consumed on the resistor, which is converted into heat. For the heating wire, the electric energy power is completely converted into heat energy / heat. The Joule heat generated by the heating wire: Q = P·t = (I^2 / R)·t or P = V·I·t.

[0037] Q: heat (J); P: power value (W); t: working time of the heating system (s); I: current value (A) passing through the heating wire; V: voltage value (V) across the heating wire when power is applied; R: resistivity of the heating wire (Ω).

[0038] The stable working voltage and current of the heating wire are 8.4V and 3.4A (for a certain type of LED module), respectively, and the generated power / heat energy is 28.56W*working time (t).

[0039] The PCB base layer 10 includes a power supply circuit layer capable of connecting a power supply, and the heating layer 40 is electrically connected to the power supply circuit layer. Specifically, the positive and negative electrodes of the heating wire of the heating layer are connected to the power supply circuit layer (a wiring layer for connecting external power supply and signal) in a through hole (surface copper plating, to ensure stable connection) mode. To ensure safety, the layer is connected to the GND wiring layer (ground layer) (the connection mode is through multiple buried holes or through holes, which depends on the distance and position of the nearest GND).

[0040] In the embodiment, the LED module further includes a first temperature sensor, a second temperature sensor and a controller, the first temperature sensor and the second temperature sensor are electrically connected to the controller, the first temperature sensor is used to detect the temperature of the part of the LED module corresponding to the heating layer 40, and the second temperature sensor is used to detect the temperature of the remaining part of the LED module. The controller controls the working of the heating layer 40 according to the temperature information of the first temperature sensor and the second temperature sensor, so as to timely control the working of the heating layer 40, so that the display screen has good display effect. Specifically, the first temperature sensor and the second temperature sensor are both NTC thermistors.

[0041] Specifically, the controller is a microcontroller that receives data from two temperature sensors and processes the temperature data using an internal PID control algorithm. The controller activates the heating layer via a drive circuit, such as a relay, solid-state relay (SSR), or transistor, which then switches the power supply to the heating layer on and off according to the controller's instructions.

[0042] The controller includes a clock circuit that provides a timing function. The controller uses the clock circuit to periodically acquire temperature information (the temperature difference between the first and second temperature sensors) from the first and second temperature sensors to check for temperature differences within specific time intervals. If the temperature difference exceeds a preset value (let's assume it's 3°C for clarity), the controller generates a signal to activate the heating layer.

[0043] The LED module includes a small-pitch direct-view LED module.

[0044] Another embodiment of this utility model provides a display screen, which includes a housing and an LED module disposed on the housing. The LED module is the LED module provided above. Therefore, this display screen can also reduce or even eliminate the temperature difference between the edge of the LED module and the rest of the screen, greatly improving the color difference of the LED module. As a result, the white-cyan distribution phenomenon of the screen in related technologies is eliminated, and the display effect of the display screen is greatly improved.

[0045] In this embodiment, the width of the heating layer 40 of the LED module is equal to the size of the portion of the edge of the LED module that overlaps with the housing. The heating layer 40 provides better heat replenishment, thereby greatly improving the display effect of the screen.

[0046] Another embodiment of this utility model provides a control method for an LED module. This control method is used to control the operation of the LED module provided above. The control method for the LED module includes:

[0047] S100: Use the first temperature sensor to collect the first temperature of the corresponding part of the heating layer 40 of the LED module, and use the second temperature sensor to collect the second temperature of the remaining part of the LED module.

[0048] S200: Compare the difference between the first temperature and the second temperature with a preset value. If the difference between the first temperature and the second temperature is less than or equal to the preset value, the controller controls the heating layer 40 to stop heating. If the difference between the first temperature and the second temperature is greater than the preset value, the controller controls the heating layer 40 to start heating.

[0049] S300, after the heating layer 40 starts heating, the third temperature of the part of the LED module corresponding to the heating layer 40 is collected by the first temperature sensor, and the fourth temperature of the remaining part of the LED module is collected by the second temperature sensor;

[0050] S400, the difference between the third temperature and the fourth temperature is compared with the preset value, and when the difference between the third temperature and the fourth temperature is less than or equal to the preset value, the controller controls the heating layer 40 to stop heating.

[0051] The control method of the LED module is adopted, the first temperature sensor and the second temperature sensor are used to detect the temperature of the LED module in time, the working state of the heating layer 40 is controlled in time by the controller, and the display effect of the display screen can be adjusted in time.

[0052] In addition, the control method of the LED module can control the on-off of the heating layer through signals, and can achieve the following two purposes: 1) safe use, without long-term uninterrupted use of the heating layer; 2) accurate temperature control, stable voltage and current.

[0053] In order to achieve the above purpose, the signal of the PCB base layer (containing the integrated control layer of the whole module driving, brightness control, scanning control, power control and other functions) will be laid through the line to the heating layer, and the feedback and command signal of the heating layer will be received and transmitted.

[0054] In this embodiment, the control method of the LED module further comprises: S410, when the difference between the third temperature and the fourth temperature is greater than the preset value, the controller adjusts the heating power of the heating layer 40 according to the difference between the third temperature and the fourth temperature, so as to reduce the temperature difference between the edge and the middle of the LED module in time.

[0055] Specifically, the controller controls the heating power of the heating layer 40 through the PWM (pulse width modulation, Pulse-Width Modulation) signal to accurately adjust the temperature of the edge of the LED module.

[0056] In this embodiment, the control method of the LED module further comprises: S210, setting the working temperature of the heating layer 40 according to the heating temperature of the LED lamp bead layer 30 of the LED module.

[0057] In this embodiment, when the LED module is lit, the heating layer will not work immediately (circuit control), and needs to start working after a period of time (the time is an experimental value, and the time related value is written into the control program when the obvious color difference caused by the temperature difference between the middle and the periphery of the LED module is obtained through experiment). The white-blue distribution phenomenon of the screen body will be eliminated, and the color gamut display of the direct display LED module will be greatly improved.

[0058] The device and method provided by the embodiment have the following beneficial effects:

[0059] (1) Since the heating layer 40 is arranged between the PCB base layer 10 and the LED circuit layer 20, the heating layer 40 emits heat when the LED module works, so that the heat of the LED lamp bead layer 30 is not easily transmitted downward, the temperature difference between the edge and the rest of the LED module is reduced or even eliminated, the color difference of the LED module is greatly improved, and the white-blue distribution phenomenon of the screen body in the related art is eliminated, and the display effect of the display screen is greatly improved.

[0060] (2) The first temperature sensor and the second temperature sensor are used to detect the temperature of the LED module in time, so that the controller can control the working state of the heating layer 40 in time, and then the display effect of the display screen can be adjusted in time.

[0061] It should be noted that the terms used herein are only intended to describe specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, the singular form is intended to include the plural form, unless the context clearly indicates otherwise, and it should be understood that, when the terms "comprise" and / or "include" are used in the specification, there is a presence of the features, steps, operations, devices, components and / or combinations thereof.

[0062] Unless otherwise specifically stated, the relative arrangements of parts and steps, numerical expressions, and numerical values set forth in these embodiments are not meant to limit the scope of the present application. At the same time, it should be understood that the sizes of the various parts shown in the drawings are not drawn in accordance with the actual proportion relationship. The technology, methods and devices known to those skilled in the art may not be discussed in detail, but should be considered as part of the specification under appropriate circumstances. In all examples shown and discussed herein, any specific value should be interpreted as merely exemplary, not as a limitation. Therefore, other examples of exemplary embodiments can have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further discussed in subsequent drawings.

[0063] In the description of the utility model, it is understood that the orientation words such as '' front, back, up, down, left, right '' '' horizontal, vertical, perpendicular, horizontal '' and '' top, bottom '' and the like indicated orientation or positional relationship is usually based on the orientation or positional relationship shown in the drawings, only for the convenience of describing the utility model and simplifying the description, in the absence of the opposite statement, these orientation words do not indicate and imply that the device or element indicated must have a particular orientation or be constructed and operated in a particular orientation, therefore can not be understood as the limitation of the protection scope of the utility model;The orientation words '' inside, outside '' refer to the inside and outside relative to the contour of each component.

[0064] For the convenience of description, spatial relative terms such as '' above'', '' above'', '' upper surface'', '' upper '' and the like can be used here to describe the spatial position relationship of one device or feature with other devices or features as shown in the drawing. It should be understood that the spatial relative terms are intended to include different orientations in use or operation in addition to the orientation of the device described in the drawing. For example, if the device in the drawing is inverted, the device described as '' above '' or '' above '' other devices or structures will be positioned '' below '' or '' below '' other devices or structures. Thus, the exemplary term '' above '' can include both '' above '' and '' below '' orientations. The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative description used here is interpreted accordingly.

[0065] In addition, it should be noted that the use of '' first'', '' second '' and the like to limit parts is only for the convenience of distinguishing the corresponding parts, and the above words have no special meaning unless otherwise stated, therefore can not be understood as the limitation of the protection scope of the utility model.

[0066] The above only describes the preferred embodiments of the utility model, and is not used to limit the utility model, for those skilled in the art, the utility model can have various changes and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the utility model should be included in the protection scope of the utility model.

Claims

1. An LED module, characterized in that, The LED module comprises: a PCB base layer (10); an LED circuit layer (20) arranged above the PCB base layer (10); an LED lamp bead layer (30) arranged above the LED circuit layer (20) and electrically connected with the LED circuit layer (20); a heating layer (40) arranged between the PCB base layer (10) and the LED circuit layer (20), the heating layer (40) being in a ring structure surrounding the edge of the PCB base layer (10).

2. The LED module of claim 1, wherein, The LED module further comprises a first insulating layer (50) and a second insulating layer (60), the heating layer (40) being sandwiched between the first insulating layer (50) and the second insulating layer (60), the upper surface of the heating layer (40) being in conformity with the lower surface of the first insulating layer (50), and the lower surface of the heating layer (40) being in conformity with the upper surface of the second insulating layer (60).

3. The LED module of claim 1, wherein, The thickness of the heating layer (40) is between 0.05mm and 0.08mm.

4. The LED module of claim 1, wherein, The width of the heating layer (40) is between 3mm and 4mm.

5. The LED module of claim 1, wherein, The heating layer (40) is made of nickel-chromium alloy.

6. The LED module of claim 1, wherein, The PCB base layer (10) comprises a power supply circuit layer capable of connecting a power supply, and the heating layer (40) is electrically connected with the power supply circuit layer.

7. The LED module according to any one of claims 1 to 6, characterized in that, The LED module further comprises a controller, and a first temperature sensor and a second temperature sensor electrically connected with the controller, the first temperature sensor being used for detecting the temperature of the part of the LED module corresponding to the heating layer (40), the second temperature sensor being used for detecting the temperature of the rest of the LED module, and the controller controlling the working of the heating layer (40) according to the temperature information of the first temperature sensor and the second temperature sensor.

8. The LED module of claim 7, wherein, The controller has a clock circuit, and the controller acquires the temperature information of the first temperature sensor and the second temperature sensor by using the clock circuit.

9. A display screen, characterized by The display screen comprises a box body and an LED module arranged on the box body, the LED module being the LED module according to any one of claims 1 to 8.

10. The display screen of claim 9, wherein, The width of the heating layer (40) of the LED module is equal to the size of the part of the LED module where the edge coincides with the box body.

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