LED filament and LED light bulb
An LED filament and an LED light bulb applying the same are provided. The LED filament includes a conductive section including a conductor; two or more LED sections connected to each other by the conductive section, and each of the LED sections includes two or more LED chips electrically connected to each other through a wire; two electrodes, electrically connected to the LED section; and a light conversion layer with a top layer and a base layer, covering the LED sections, the conductive section and the two electrodes, and a part of each of the two electrodes is exposed respectively. The LED filament is supplied with electric power no more than 8 W, when the LED filament is lit, at least 4 lm of white light is emitted per millimeter of filament length.
1. An LED light bulb, comprising:
a lamp housing, filled with gas including nitrogen and oxygen, where the oxygen content is 1% to 5% of a volume of the lamp housing;
a bulb base connected to the lamp housing;
a stem connected to the bulb base and located in the lamp housing; and
a single LED filament, disposed in the lamp housing and the LED filament comprising:
a conductive section, comprising a conductor;
at least two LED sections connected to each other by the conductive section, and each of the LED sections comprises at least two LED chips electrically connected to each other through a wire;
two electrodes, electrically connected to the LED section; and
a light conversion layer with a top layer and a base layer, covering the at least two LED sections, the conductive section and the two electrodes, and a part of each of the two electrodes is exposed respectively; wherein the base layer of the light conversion layer is a silicone-modified polyimide resin composition composite film;
a Cartesian coordinate system having an X-axis, a Y-axis and a Z-axis is oriented for the LED light bulb, where the Z-axis is parallel to the stem, wherein W1 is a diameter of the bulb base, W2 is a maximum diameter of the lamp housing or a maximum horizontal dimension of the lamp housing in the Y-Z plane, and W3 is a maximum width of the LED filament in the Y-axis direction on the Y-Z plane or the maximum width in the X-axis direction on the X-Z plane, where W1<W3<W2.
2. The LED light bulb according to claim 1 , wherein the LED filament has at least two first bending points and at least one second bending point when the LED filament is bent.
3. The LED light bulb according to claim 2 , wherein the at least two first bending points and the at least one second bending point are arranged alternately.
4. The LED light bulb according to claim 2 , wherein a height of any one of the at least two first bending points on the Z-axis is greater than a height of any one of the at least one second bending point.
5. The LED light bulb according to claim 2 , wherein the LED filament has a plurality of the first bending points, distances between any of two adjacent first bending points of the first bending points on the Y-axis are equal or distances between any of two adjacent first bending points of the first bending points on the Z-axis are equal.
6. The LED light bulb according to claim 2 , wherein the LED filament has a plurality of the first bending points, a distance between two adjacent first bending points of the first bending points on the Y-axis has a maximum value D1 and a minimum value D2, or a distance between two adjacent first bending points of the first bending points on the X-axis has the maximum value D1 and the minimum value D2, wherein a range of D2 is from 0.5*D1 to 0.9*D1.
7. The LED light bulb according to claim 1 , wherein the LED filament includes one conductor section and two LED sections, where a bending point of each of the two LED sections and each of the two electrodes are located substantially on a circumference of a circle taking the conductor section as a center.
8. The LED light bulb according to claim 7 , wherein the LED filament comprises a plurality of the LED sections, and each of the LED sections comprises a plurality of the LED chips, a shortest distance between two LED chips of the LED chips located respectively in two adjacent LED sections is greater than a distance between two adjacent LED chips of the LED chips in the same LED section.
9. The LED light bulb according to claim 8 , wherein a length of the wire is shorter than a length of the conductor.
10. The LED light bulb according to claim 1 , wherein an impurity is attached to the inner wall of the lamp housing, where an average thickness of the impurity deposited per square centimeter of an inner wall area of the lamp housing is 0.01 to 2 mm.
11. The LED light bulb according to claim 10 , wherein a spectral distribution of the light bulb is between a wavelength range of about 400 nm to 800 nm, and three peak wavelengths P1, P2, and P3 appear in wavelength ranges corresponding to light emitted by the light bulb, wherein a wavelength of the peak P1 is between 430 nm and 480 nm, a wavelength of the peak P2 is between 580 nm and 620 nm, and a wavelength of the peak P3 is between 680 nm and 750 nm, wherein a light intensity of the peak P1 is less than a light intensity of the peak P2, and the light intensity of the peak P2 is less than a light intensity of the peak P3.