CN106382609B

CN106382609B - LED filament strip

Info

Publication number: CN106382609B
Application number: CN201610904157.6A
Authority: CN
Inventors: 于天宝; 佘君; 章少华
Original assignee: Nanchang University
Current assignee: Nanchang University
Priority date: 2016-10-18
Filing date: 2016-10-18
Publication date: 2023-05-30
Anticipated expiration: 2036-10-18
Also published as: CN106382609A

Abstract

The invention provides an LED (light emitting diode) filament, which comprises the following components: the LED lamp comprises a strip-shaped bracket, electrode pins arranged at two ends of the strip-shaped bracket, printed conductive wires arranged on the surface of the strip-shaped bracket and a plurality of LED chips connected with each other through the printed conductive wires, wherein the printed conductive wires are axisymmetrically arranged on the surface of the strip-shaped bracket and are divided into two rows of parallel arrangement; when the printed conductive wires in each row are odd, a plurality of LED chips are connected end to end and are welded on the printed conductive wires in sequence in a central symmetry mode; when the printed conductive wires included in each row are even, the LED chips are connected end to end and are welded on the printed conductive wires in sequence in an axisymmetric mode. Therefore, 360-degree light emission of the LED filament strip is realized, the uniformity of the spatial distribution of the light field of the LED filament strip is greatly improved, and glare is not generated by people, so that the purpose of protecting eyesight of people is achieved, and the requirements of the LED lamp illumination design are met.

Description

LED filament strip

Technical Field

The invention relates to the technical field of LEDs, in particular to an LED filament strip.

Background

The LED light source has the characteristics of high luminous efficiency, energy conservation, environmental protection, long service life and the like, and is called as a green illumination light source. The LED adopting the flip-chip technology has the advantages of high light extraction efficiency, low thermal resistance, high reliability and the like. Meanwhile, the LED filament lamp has the advantages of 360-degree light emission, integrated high-voltage driving, compliance with the traditional lighting use habit and the like.

With the continuous appearance of new materials and the continuous appearance of new processes, LED lamp strips capable of comprehensively emitting light are appeared on the market in recent years. The LED filament strip is generally formed by arranging LED chips 4 which are arranged in a straight line shape on a strip-shaped bracket 2 in a serial connection mode, as shown in figure 1, wherein 1 is an electrode pin, and 3 is a printed conductive circuit; and silver plating layers 5 are arranged at equal intervals below the two ends of the chip electrode, as shown in fig. 2, and the chip is fixed on the silver plating layers through eutectic soldering technology to complete electrical interconnection.

However, the arrangement mode of the chips in the filament is too single, the distribution of the spatial light field is uneven, the illuminance uniformity of the bottom receiving surface is poor, and people can easily generate glare, so that severe changes of pupils of eyes are caused, visual fatigue is aggravated, visual nerves are damaged, and the visual acuity of the eyes is negatively influenced.

Disclosure of Invention

Aiming at the problems, the invention provides an LED filament strip, which effectively solves the technical problem of uneven light emission of the existing LED filament strip.

The technical scheme provided by the invention is as follows:

an LED filament strip comprising: the LED device comprises a bar-shaped bracket, electrode pins arranged at two ends of the bar-shaped bracket, printed conductive wires arranged on the surface of the bar-shaped bracket and a plurality of LED chips connected with each other through the printed conductive wires,

the printed conductive wires are axisymmetrically arranged on the surface of the strip-shaped support and are divided into two rows and arranged in parallel;

when the printed conductive lines in each row are odd, the LED chips are connected end to end and are welded on the printed conductive lines in sequence in a central symmetry mode;

when the printed conductive lines included in each row are even, the LED chips are connected end to end and are welded on the printed conductive lines in sequence in an axisymmetric mode.

Further preferably, the LED chip is a flip-chip LED chip.

Further preferably, the printed conductive lines are axisymmetrically arranged on the surface of the bar-shaped bracket and are divided into two rows of parallel arrangement, and specifically include:

the printed conductive wires are divided into two rows and are arranged on the strip-shaped support in parallel, and the printed conductive wires in each row are uniformly and axisymmetrically arranged at equal intervals.

Further preferably, in the two rows of printing conductive wires, an LED chip is arranged between each printing conductive wire; in each row of printed conductive wires, the LED chips are arranged between every two printed conductive wires at intervals and distributed in the two rows of printed conductive wires in a staggered way, so that an LED filament strip structure with a plurality of LED chips connected end to end and connected to the strip-shaped support in series is formed.

Compared with the prior art, the invention has the beneficial effects that:

in the LED lamp filament strip provided by the invention, the flip LED chips are connected on the printed conductor in series end to end, so that 360-degree light emission of the LED lamp filament strip is realized, the uniformity of light field spatial distribution of the LED lamp filament strip is greatly improved, glare is not generated by people, the purpose of protecting eyesight of people is achieved, and the requirements of LED lamp illumination design are met.

In addition, the arrangement mode of the LED chips in the LED filament strip provided by the invention increases the number of the LED chips in the unit area on the strip-shaped bracket, so that the total luminous power of the LED filament strip is greatly improved.

Drawings

The above features, technical features, advantages and implementation thereof will be further described in the following detailed description of preferred embodiments with reference to the accompanying drawings in a clearly understandable manner.

FIG. 1 is a schematic view of a prior art LED filament strip;

FIG. 2 is a schematic view of a prior art filament bar support structure;

FIG. 3 is a schematic structural view of an embodiment of an LED filament strip according to the present invention;

FIG. 4 is a schematic view of another embodiment of an LED filament strip according to the present invention;

FIG. 5 is a ray trace of the prior art LED filament strip of FIG. 1/FIG. 2 during operation;

FIG. 6 is a graph showing an illuminance distribution on a light receiving surface of the ray trace of FIG. 5;

FIG. 7 is a ray trace of the LED filament strip of FIG. 3 during operation;

FIG. 8 is a graph showing the illuminance distribution of the light receiving surface in the ray trace of FIG. 7;

reference numerals illustrate:

the LED chip comprises 1-electrode pins, 2-bar-shaped brackets, 3-conductive circuits, 4-LED chips and 5-silver plating layers.

Detailed Description

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following description will explain the specific embodiments of the present invention with reference to the accompanying drawings. It is evident that the drawings in the following description are only examples of the invention, from which other drawings and other embodiments can be obtained by a person skilled in the art without inventive effort.

The invention provides an LED (light emitting diode) filament, which comprises the following components: the LED lamp comprises a strip-shaped support 2, electrode pins 1 arranged at two ends of the strip-shaped support, printed conductive wires 3 arranged on the surface of the strip-shaped support and a plurality of LED chips 4 connected with each other through the printed conductive wires, wherein the printed conductive wires are axisymmetrically arranged on the surface of the strip-shaped support and are divided into two rows of parallel arrangement. More specifically, when the printed conductive wires included in each row are odd, the LED chips are connected end to end and are soldered on the printed conductive wires in turn in a central symmetry, as shown in fig. 3 (each row includes 7 printed conductive wires); when the number of printed conductor lines included in each row is even, the LED chips are connected end to end and soldered on the printed conductor lines in turn in axisymmetric fashion, as shown in fig. 4 (each row includes 6 printed conductor lines).

In a specific embodiment, the LED chip on the support is a flip-chip LED chip. And the printed conductive wires are divided into two rows and arranged on the strip-shaped support in parallel, and the printed conductive wires in each row are uniformly and axisymmetrically arranged at equal intervals. In the two rows of printing conductive wires, an LED chip is arranged between each printing conductive wire; in each row of printed conductive wires, the LED chips are arranged between every two printed conductive wires at intervals and distributed in the two rows of printed conductive wires in a staggered way, so that an LED filament strip structure with a plurality of LED chips connected end to end and connected to the strip-shaped support in series is formed.

In the welding process, a proper amount of solder paste is coated on the printed conducting wires, the positive electrode and the negative electrode of the flip LED chip are respectively aligned to the two printed conducting wires on the strip-shaped support, and the welding between the flip LED chip and the printed conducting wires is realized in a reflow soldering mode. Specifically, from one end of the bar-shaped support, the flip-chip LED chip is welded on the printed conductive wires connected with the electrode pins, then the flip-chip LED chip is sequentially welded between the printed conductive wires in a serial manner (the positive electrode of one flip-chip LED chip and the negative electrode of the other flip-chip LED chip are respectively welded on one printed conductive wire) until reaching the other end of the bar-shaped support, and the electrode of the flip-chip LED chip is LED out to the electrode pins, so that the conduction of each flip-chip LED chip is realized.

Fig. 5 is a light trace diagram of the LED filament strip shown in fig. 1 and 2 during operation, and it can be seen from the figure that a larger light receiving surface is included below, and the illuminance distribution diagram of the light receiving surface is shown in fig. 6. In a specific embodiment, the chip size, the material, the light emitting power, the size height of the light receiving surface and the total length of the transverse chip are kept unchanged from those of the LED filament strips shown in fig. 1/2, the LED chips are arranged and welded according to the LED filament strip structure shown in fig. 3, and a ray trace diagram obtained in the structure is shown in fig. 7, and a corresponding light receiving surface illumination diagram is shown in fig. 8.

As is known from illuminance uniformity=1- (root mean square deviation/average illuminance), the illuminance uniformity is better as the illuminance uniformity value is closer to 1. As can be obtained by calculation from the illuminance data of several points in fig. 6, the minimum value of the illuminance of the LED filament strip is 0.021148Lx, the maximum value is 63864Lx, the average illuminance is 14067Lx, the root mean square deviation is 13501, and the uniformity is 0.0402 as shown in fig. 1 and 2. In the LED filament shown in fig. 3, the minimum value of illuminance 140.44Lx, the maximum value of 87966Lx, the average illuminance 30515Lx, the root mean square deviation equal to 13447, and the uniformity of 0.5593. It is obvious that the illuminance uniformity of the LED filament strip in the example is greatly improved compared with that of the traditional filament.

Based on the specific embodiment provided above, the LED lamp filament light field distribution device can be popularized and applied to the condition (the quantity is not unique) of a plurality of LED chips, the LED chips can be forward-mounted LED chips, and the LED chips are connected in series through bonding wires, so that the purpose of the LED lamp filament light field distribution device can be achieved according to the embodiment structure, and the spatial uniformity of the LED lamp filament light field distribution can be greatly improved.

Claims

1. An LED filament strip, wherein the LED filament strip comprises: the LED lamp comprises a strip-shaped bracket, electrode pins arranged at two ends of the strip-shaped bracket, printed conductive wires arranged on the surface of the strip-shaped bracket and a plurality of LED chips connected with each other through the printed conductive wires, wherein the printed conductive wires are axisymmetrically arranged on the surface of the strip-shaped bracket and are divided into two rows to be arranged in parallel; when the printed conductive lines in each row are odd, the LED chips are connected end to end and are welded on the printed conductive lines in sequence in a central symmetry mode; when the printed conductive lines in each row are even, the LED chips are connected end to end and are welded on the printed conductive lines in sequence in an axisymmetric mode;

in the two rows of printing conductive wires, an LED chip is arranged between each printing conductive wire; in each row of printed conductive wires, the LED chips are arranged between every two printed conductive wires at intervals and distributed in the two rows of printed conductive wires in a staggered way, so that an LED filament strip structure with a plurality of LED chips connected end to end and connected in series on the strip-shaped support is formed;

the printed conductor is axisymmetric and arranged on the surface of the bar-shaped bracket, and is divided into two rows of parallel arrangement, and specifically comprises: the printed conductive wires are divided into two rows and are arranged on the strip-shaped support in parallel, and the printed conductive wires in each row are uniformly and axisymmetrically arranged at equal intervals.

2. The LED light bar of claim 1, wherein the LED chip is a flip-chip LED chip.