LED flexible lamp strip
By setting a specific exit surface structure on the transparent gel of the LED flexible light strip, the total reflection of some light is achieved, the color temperature drift problem is solved, and the lighting effect of the light strip is improved.
Patent Information
- Application Number
- CN202311792364.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-12-23
- Publication Date
- 2025-06-24
AI Technical Summary
LED flexible light strips are prone to color temperature drift during manufacturing and use, resulting in changes in the color temperature of the light strip and the color temperature of the LED lamp beads.
By providing a first exit surface opposite to the flexible circuit board and a second exit surface disposed on the transparent adhesive, and connecting the second exit surface to the first exit surface, the first exit surface is an arc surface recessed toward the flexible circuit board, thereby achieving total reflection of some light.
The total reflection of some light is increased, the color temperature drift is reduced, and the overall lighting effect of the light strip is improved.
Smart Images
Figure CN120194282A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to an LED flexible light strip, belonging to the technical field of LED light strips. Background Art
[0002] The application of LED flexible light strips is becoming more and more extensive. In the market, the epoxy resin LED flexible light strip is to paste LED lamp beads on a prefabricated flexible PCB board by SMT, and coat the surface of the light strip with optical grade transparent glue. After the glue is cured, it adheres to the circuit board and the LED lamp beads to form protection for the PCB board and the LED lamp beads. At the same time, due to the refraction and scattering of the LED light by the cured glue, a better optical effect is obtained, and the epoxy resin LED flexible light strip can also be used for a long time. However, it is found in the manufacturing and use that the color temperature of the light strip after epoxy resin coating has changed from that of the LED lamp beads used for the light strip, that is, the color temperature drift phenomenon.
[0003] In view of this, it is necessary to improve the existing LED flexible light strip to solve the above problems. Summary of the Invention
[0004] The purpose of the present invention is to provide an LED flexible light strip, which can increase the total internal reflection of part of the light, thereby reducing the color temperature drift and improving the overall lighting effect of the light strip.
[0005] To achieve the above purpose, the present invention provides an LED flexible light strip, including a flexible circuit board, a plurality of LED light sources mounted on the flexible circuit board, and a transparent glue bonded to the flexible circuit board and the LED light sources. The LED light source includes a lamp bead and a fluorescent glue wrapping the lamp bead. The transparent glue covers the flexible circuit board and has a first exit surface opposite to the flexible circuit board and second exit surfaces respectively arranged on both sides of the first exit surface. The second exit surfaces are connected to the first exit surface. The first exit surface is an arc surface recessed towards the flexible circuit board, so that after the first light emitted by the LED light source reaches the first exit surface, part of it is reflected to the second exit surface to form second light, and the second light is reflected to the fluorescent glue of the LED light source and then re-emitted.
[0006] As a further improvement of the present invention, a corner is formed at the connection between the first exit surface and the second exit surface, and the corner is generally a right angle.
[0007] As a further improvement of the present invention, the fluorescent glue is arranged in a cuboid shape, the fluorescent glue contains fluorescent powder, and the second light is reflected from the second exit surface to the fluorescent glue and emitted after exciting the fluorescent powder.
[0008] As a further improvement of the present invention, a third light-emitting surface is formed between the fluorescent glue and the transparent glue. The lamp bead emits a third light ray within the fluorescent glue, and the third light ray forms the first light ray after being emitted from the third light-emitting surface.
[0009] As a further improvement of the present invention, the third light-emitting surface has a second critical angle. When the emission angle of the third light ray is less than the second critical angle, the third light ray coincides with the first light ray after being emitted from the third light-emitting surface; when the emission angle of the third light ray is greater than the second critical angle, the third light ray is reflected from the third light-emitting surface to the fluorescent glue and is emitted after exciting the phosphor.
[0010] As a further improvement of the present invention, the first light-emitting surface has a first critical angle. When defining the first critical angle, the emission angle of the first light ray is used as the reference emission angle. When the emission angle of the first light ray is less than the reference emission angle, the first light ray is directly emitted from the first light-emitting surface; when the emission angle of the first light ray is greater than the reference emission angle and the first light ray reaches the first light-emitting surface, the first light ray is reflected to the second light-emitting surface to form the second light ray.
[0011] As a further improvement of the present invention, when the emission angle of the first light ray is greater than the reference emission angle but does not reach the first light-emitting surface, the first light ray is directly emitted from the transparent glue.
[0012] As a further improvement of the present invention, the reference emission angle is less than the first critical angle.
[0013] As a further improvement of the present invention, the transparent glue includes a first light-emitting portion and a second light-emitting portion. The first light-emitting portion is bonded to the flexible circuit board, and the second light-emitting portion is located on the side of the first light-emitting portion away from the flexible circuit board. The first light-emitting surface is the upper surface of the second light-emitting portion, and the second light-emitting surface is the two side surfaces of the second light-emitting portion.
[0014] As a further improvement of the present invention, the first light-emitting portion is arranged in a cuboid shape, the width of the second light-emitting portion is less than the width of the first light-emitting portion, and the second light-emitting portion is located at the middle position of the first light-emitting portion.
[0015] The beneficial effects of the present invention are as follows: By providing a first light-emitting surface opposite to the flexible circuit board and second light-emitting surfaces disposed on both sides of the first light-emitting surface on the transparent adhesive, and the second light-emitting surfaces are connected to the first light-emitting surface, and the first light-emitting surface is an arc surface recessed towards the flexible circuit board, when the first light emitted by the LED light source reaches the first light-emitting surface, a part of it can be reflected to the second light-emitting surface to form a second light, and the second light is then reflected to the fluorescent glue of the LED light source and re-emitted. Compared with the prior art, the LED flexible light strip of the present invention can achieve total internal reflection of part of the light, thereby reducing color temperature drift and improving the overall lighting effect of the light strip. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Figure 1 FIG. is a schematic perspective view of the LED flexible light strip of the present invention.
[0017] Figure 2 is Figure 1 an exploded view of the LED flexible light strip in FIG.
[0018] Figure 3 is Figure 1 a sectional view of the LED flexible light strip in FIG.
[0019] Figure 4 is Figure 3 an optical path diagram of the LED light source in FIG.
[0020] Figure 5 is Figure 4 an optical path diagram of the first light in FIG.
[0021] Figure 6 is Figure 1 a schematic perspective view of the LED flexible light strip from another angle in FIG. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0022] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.
[0023] Please refer to Figures 1-6 As shown in FIG., the present invention discloses an LED flexible light strip 100, which includes a flexible circuit board 1, a plurality of LED light sources 2 mounted on the flexible circuit board 1, and a transparent adhesive 3 bonded to the flexible circuit board 1 and the LED light sources 2. The LED light source 2 includes a lamp bead 22 and a fluorescent glue 21 wrapping the lamp bead 22. The LED light source 2 is mounted at the middle position of the flexible circuit board 1. Four LED light sources 2 are arranged in a group and evenly arranged on the flexible circuit board. The LED flexible light strip 100 can increase the total internal reflection of the light emitted by the LED light source 2, reduce color temperature drift, and improve the overall lighting effect of the light strip.
[0024] The transparent adhesive 3 covers the flexible circuit board 1 and has a first light-emitting surface 31 opposite to the flexible circuit board 1 and second light-emitting surfaces 32 respectively disposed on both sides of the first light-emitting surface 31. The second light-emitting surfaces 32 are connected to the first light-emitting surface 31. The first light-emitting surface 31 is an arc surface recessed toward the flexible circuit board 1. So that after the first light A emitted by the LED light source 2 reaches the first light-emitting surface 31, a part of it is reflected to the second light-emitting surface 32 to form a second light B, and the second light B is reflected to the phosphor 21 of the LED light source 2 and then re-emitted to improve the color temperature drift problem of the light strip.
[0025] Preferably, the phosphor 21 is arranged in a cuboid shape, the lamp bead 22 is located at the center of the phosphor 21, the light emitted by the lamp bead 22 is emitted from the center of the phosphor 21, the phosphor 21 contains phosphor powder, and the second light B is reflected from the second light-emitting surface 32 to the phosphor 21 and emitted after exciting the phosphor powder.
[0026] In this embodiment, the lamp bead 22 is a blue light chip. The lamp bead 22 emits light, and more light undergoes total reflection to be re-excited by the phosphor powder and then emitted, so that the proportion of the emitted blue light is reduced, and the color temperature drift problem is improved. The lamp bead 22 can also be an element that emits light of other colors, which is not limited here.
[0027] Specifically, a corner (not labeled) is formed at the connection between the first light-emitting surface 31 and the second light-emitting surface 32. The corner is generally a right angle. Preferably, when the corner is 90°, the best effect is achieved, so that the first light A can reach the second light-emitting surface 32 after changing direction, and the second light B is reflected back to the phosphor 21 to re-excite the phosphor powder, thereby achieving the effect of reducing the color temperature drift.
[0028] A third light-emitting surface 33 is formed between the phosphor 21 and the transparent adhesive 3. The lamp bead 22 emits a third light C in the phosphor 21. The third light C is emitted from the third light-emitting surface 33 to form the first light A. The third light C and the first light A have different emission angles. The third light C can be emitted from the third light-emitting surface 33 and coincide with the first light A, or under certain conditions, the third light C undergoes total reflection and is reflected back into the phosphor 21 from the third light-emitting surface 33.
[0029] Specifically, the third exit surface 33 has a second critical angle. When the exit angle of the third light ray C is less than the second critical angle, the third light ray C coincides with the first light ray A after exiting from the third exit surface 33; when the exit angle of the third light ray C is greater than the second critical angle, the third light ray C is reflected from the third exit surface 33 to the fluorescent glue 21 and exits after exciting the phosphor.
[0030] The first exit surface 31 has a first critical angle. When defining the first critical angle, the exit angle of the first light ray A is used as the reference exit angle. When the exit angle of the first light ray A is less than the reference exit angle, the first light ray A directly exits from the first exit surface 31; when the exit angle of the first light ray A is greater than the reference exit angle and the first light ray A reaches the first exit surface 31, the first light ray A is reflected to the second exit surface 32 to form the second light ray B. When the exit angle of the first light ray A is greater than the reference exit angle but does not reach the first exit surface 31, the first light ray A directly exits from the transparent glue 3.
[0031] In this embodiment, the refractive index of the transparent glue 3 is 1.45, the refractive index of the fluorescent glue 21 is 1.54, and the refractive index of air is 1. When light exits at the transparent glue 3 - air interface, the critical angle of light refraction θ = arcsin(1 / 1.45) = 44°. When the incident angle of light is greater than 44°, total internal reflection of light will occur. When light exits at the fluorescent glue 21 - transparent glue 3 interface, the critical angle of light refraction θ = arcsin(1.45 / 1.54) = 70°. When the incident angle of light is greater than 70°, total internal reflection of light will occur. That is, the first critical angle is 44°, the reference exit angle is 40° at this time, and the second critical angle is 70°. As Figure 5 shown, since the first exit surface 31 is an indented arc surface, the incident angle of the first light ray A reaching the first exit surface 31 is greater than the exit angle of the first light ray A from the third exit surface 33. That is to say, when the reference exit angle is greater than 40°, it can satisfy that the incident angle of the first light ray A reaching the first exit surface 31 is greater than 44°.
[0032] Specifically, when the emission angle of the third light ray C is less than 70°, the third light ray C coincides with the first light ray A after being emitted from the third emission surface 33; when the emission angle of the third light ray C is greater than 70°, the third light ray C is reflected from the third emission surface 33 to the fluorescent glue 21, and is emitted after exciting the fluorescent powder. When the emission angle of the first light ray A is less than 40°, the first light ray A is emitted directly from the first emission surface 31; when the emission angle of the first light ray A is greater than 40° and the first light ray A is emitted to the first emission surface 31, the first light ray A is reflected to the second emission surface 32 to form the second light ray B, and the second light ray B is reflected to the fluorescent glue 21, and is emitted after exciting the fluorescent powder; when the emission angle of the first light ray A is greater than 40° but is not emitted to the first emission surface 31, the first light ray A is emitted directly from the transparent glue 3. It can be understood that the first exit surface 31 is an inwardly recessed arc surface. When the exit angle of the first light ray A is greater than 40°, the incident angle of the first light ray A after it hits the first exit surface 31 is greater than 44°, and the first light ray A will be totally reflected.
[0033] That is to say, when the third light C is at an exit angle greater than 70° and when the first light A is at an exit angle greater than 40° and is emitted to the first exit surface 31, they can be reflected to the fluorescent glue 21 and emitted after exciting the fluorescent powder, thereby increasing the total reflection of the light, and more light is emitted after secondary excitation of the fluorescent powder, thereby further improving the color temperature drift problem of the LED flexible light strip 100. Preferably, when the exit angle of the first light A is 40°, the angle between the first light A and the end of the second exit surface 32 away from the corner is 20°.
[0034] In this embodiment, the transparent adhesive 3 includes a first light emitting portion 34 and a second light emitting portion 35, the first light emitting portion 34 is bonded to the flexible circuit board 1, the second light emitting portion 35 is located on the side of the first light emitting portion 34 away from the flexible circuit board 1, the first emitting surface 31 is the upper surface of the second light emitting portion 35, the second emitting surface 32 is the two side surfaces of the second light emitting portion 35, and the second emitting surface 32 gradually tilts inward from the connection with the first light emitting portion 34 until it is connected with the first emitting surface 31. The LED light source 2 is located in the first light emitting portion 34, the first light emitting portion 34 is arranged in a rectangular parallelepiped, the width of the second light emitting portion 35 is smaller than the width of the first light emitting portion 34, and the second light emitting portion 35 is located in the middle of the first light emitting portion 34.
[0035] In summary, in the present invention, a first light-emitting surface 31 opposite to the flexible circuit board 1 and second light-emitting surfaces 32 disposed on both sides of the first light-emitting surface 31 are provided on the transparent adhesive 3. At the same time, the second light-emitting surface 32 is connected to the first light-emitting surface 31, and the first light-emitting surface 31 is an arc surface recessed toward the flexible circuit board 1. Thus, after the first light ray A emitted by the LED light source 2 reaches the first light-emitting surface 31, a part of it will be reflected to the second light-emitting surface 32 to form a second light ray B, and the second light ray B is reflected to the phosphor of the LED light source 2 to excite the phosphor and then re-emitted. Compared with the prior art, the LED flexible light strip 100 of the present invention can increase the total reflection of some light rays, thereby reducing the color temperature drift and improving the overall lighting effect of the light strip.
[0036] The above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present invention.
Claims
1. An LED flexible light strip, comprising a flexible circuit board (1), a plurality of LED light sources (2) mounted on the flexible circuit board (1), and a transparent adhesive (3) bonded to the flexible circuit board (1) and the LED light sources (2), wherein the LED light sources (2) include lamp beads (22) and a fluorescent adhesive (21) wrapping the lamp beads (22), and is characterized in that, The transparent adhesive (3) covers the flexible circuit board (1), and has a first emission surface (31) opposite to the flexible circuit board (1) and second emission surfaces (32) respectively disposed on both sides of the first emission surface (31). The second emission surfaces (32) are connected to the first emission surface (31). The first emission surface (31) is an arc surface recessed towards the flexible circuit board (1). So that after the first light (A) emitted by the LED light source (2) reaches the first emission surface (31), a part of it is reflected to the second emission surface (32) to form a second light (B), and the second light (B) is reflected to the fluorescent glue (21) of the LED light source (2) and then re-emitted.
2. The LED flexible light strip according to claim 1, wherein: A corner is formed at the connection of the first emission surface (31) and the second emission surfaces (32), and the corner is generally a right angle.
3. The LED flexible light strip according to claim 1, characterized in that: The fluorescent glue (21) is arranged in a cuboid shape, and the fluorescent glue (21) contains phosphor powder. The second light (B) is reflected from the second emission surface (32) to the fluorescent glue (21) and emitted after exciting the phosphor powder.
4. The LED flexible light strip according to claim 3, wherein: A third emission surface (33) is formed between the fluorescent glue (21) and the transparent adhesive (3). The lamp bead (22) emits a third light (C) in the fluorescent glue (21), and the third light (C) forms the first light (A) after being emitted from the third emission surface (33).
5. The LED flexible light strip according to claim 4, characterized in that: The third emission surface (33) has a second critical angle. When the emission angle of the third light (C) is less than the second critical angle, the third light (C) coincides with the first light (A) after being emitted from the third emission surface (33); when the emission angle of the third light (C) is greater than the second critical angle, the third light (C) is reflected from the third emission surface (33) to the fluorescent glue (21) and emitted after exciting the phosphor powder.
6. The LED flexible light strip according to claim 1, characterized in that: The first emission surface (31) has a first critical angle. When defining the first critical angle, the emission angle of the first light (A) is used as the reference emission angle. When the emission angle of the first light (A) is less than the reference emission angle, the first light (A) is directly emitted from the first emission surface (31); when the emission angle of the first light (A) is greater than the reference emission angle and the first light (A) reaches the first emission surface (31), the first light (A) is reflected to the second emission surface (32) to form the second light (B).
7. The LED flexible light strip according to claim 6, wherein: When the emission angle of the first light (A) is greater than the reference emission angle but does not reach the first emission surface (31), the first light (A) is directly emitted from the transparent adhesive (3).
8. The LED flexible light strip according to claim 6, wherein: The reference emission angle is less than the first critical angle.
9. The LED flexible light strip according to claim 1, wherein: The transparent adhesive (3) comprises a first light emitting portion (34) and a second light emitting portion (35), wherein the first light emitting portion (34) is bonded to the flexible circuit board (1), the second light emitting portion (35) is located on a side of the first light emitting portion (34) that is away from the flexible circuit board (1), the first emitting surface (31) is an upper surface of the second light emitting portion (35), and the second emitting surface (32) is two side surfaces of the second light emitting portion (35).
10. The LED flexible light strip according to claim 9, characterized in that: The first light exit portion (34) is arranged in a rectangular parallelepiped, the width of the second light exit portion (35) is smaller than the width of the first light exit portion (34), and the second light exit portion (35) is located in the middle of the first light exit portion (34).