Backlight module and display device II
A display device includes a display panel, a first light source, and second light source. The first and second light sources are respectively aligned with a first spot and second spot in a direction perpendicular to a substrate. The first light source irradiates the first and second spots with luminance of a first value and second value, respectively. The first light source irradiates a midpoint between the first and second spots with a luminance value that is half the addition of the first and second values.
1 . A backlight module for a display device, comprising:
a substrate and four LED light sources disposed on the substrate, the four LED light sources forming a rectangle-shaped lighting unit,
wherein the four LED light sources are disposed at the lighting unit's four corners, respectively, the lighting unit has a length L along a first direction X and a width W along a second direction Y, and irradiates a rectangular area with the same length L and width W on an interface of the display device,
wherein a first LED light source of the four LED light sources comprises a first LED and a first lens disposed above the first LED, the first lens directing light rays emitted from the first LED onto
(1) a first corner of the rectangular area on the interface of the display device with a first luminance value E1,
(2) a second corner of the rectangular area with luminance of a first predetermined value, wherein a distance between the first corner and the second corner is L along the first direction X,
(3) a first location (x, 0) with a luminance value E(x, 0) that is determined based on a change of luminance value from the first luminance value E1 at the first corner to the first predetermined value at the second corner, wherein the first location is on a first border line between the first corner and the second corner, and x is a distance between the first location (x, 0) and the first corner along the first direction X,
(4) a third corner of the rectangular area with luminance of a second predetermined value, wherein a distance between the first corner and the third corner is W along the second direction Y,
(5) a second location (0, y) with a luminance value E (0, y) that is determined based on a change of luminance value from the first luminance value E1 at the first corner to the second predetermined value at the third corner, wherein the second location is on a second border line between the first corner and the third corner, and y is a distance between the second location (0, y) and the first corner along the second direction Y, and
(6) a third location (x, y) of the rectangular area with a luminance value of E(x, y) that is a product of E(x, 0) and E (0, y).
2 . The backlight module of claim 1 , wherein the first LED is a mini light emitting diode (mini-LED).
3 . The backlight module of claim 1 , wherein the first LED has a dimension smaller than 300 micrometers along the first direction X or second direction Y.
4 . The backlight module of claim 1 , wherein luminance uniformity in the rectangular area on the interface of the display device is beyond a predetermined value when the four LED light sources at the lighting unit's four corners irradiate the rectangular area.
5 . The backlight module of claim 1 , wherein the display device has a liquid crystal display (LCD) panel.
6 . The backlight module of claim 1 , wherein the first lens and other lenses of the four LED light sources form a rectangle with the same length L and width W.
7 . The backlight module of claim 6 , wherein the first lens and the other lenses are made by molding.
8 . The backlight module of claim 1 , wherein the change of luminance value from the first luminance value E1 at the first corner to the first predetermined value at the second corner is determined by a predetermined function.
9 . The backlight module of claim 1 , wherein the length L and width W have different values and/or are smaller than 9 millimeters, respectively.
10 . The backlight module of claim 1 , wherein a distance between the interface and the substrate is smaller than 6 millimeters.
11 . A backlight module, comprising:
a substrate;
a first light source, disposed on the substrate;
a second light source, disposed on the substrate and adjacent to the first light source with a first distance between the first and second light sources in a first direction;
a third light source, disposed on the substrate and adjacent to the first light source with a second distance between the first and third light sources in a second direction perpendicular to the first direction, the first and second distances being different;
a first lens;
a second lens; and
a third lens,
wherein the first light source, the first lens, and a first spot are aligned along a direction approximately perpendicular to the substrate, the second light source, the second lens, and a second spot are aligned along the direction, the third light source, the third lens, and a third spot are aligned along the direction, light emitted from the first light source passes through the first lens to irradiate the first spot with luminance of a first value, irradiate the second spot with luminance of a second value, irradiate the third spot with luminance of a third value, irradiate a middle spot between the first spot and the second spot with luminance of a value that is half of addition of the first and second values or substantially close to half of addition of the first and second values, and irradiate another middle spot between the first spot and the third spot with luminance of a value that is half of addition of the first and third values or substantially close to half of addition of the first and third values.
12 . The backlight module of claim 11 , wherein light emitted from the second light source passes through the second lens to irradiate the second spot with luminance of a fourth value, irradiate the first spot with luminance of a fifth value, and irradiate the middle spot with luminance of a value that is half of addition of the fourth and fifth values or substantially close to half of addition of the fourth and fifth values.
13 . The backlight module of claim 12 , wherein the first value and fourth value are substantially close and/or the second value and fifth value are substantially close.
14 . The backlight module of claim 11 , wherein the second value is below a predetermined darkness level.
15 . The backlight module of claim 11 , wherein the third value is below a predetermined darkness level.
16 . The backlight module of claim 12 , wherein the fifth value is below a predetermined darkness level.
17 . The backlight module of claim 11 , wherein the first, second, and third light sources include a mini light emitting diode (mini-LED).
18 . The backlight module of claim 11 further comprising additional light sources and additional lenses, the first, second, and third light sources and the additional light sources forming an array of light sources of a predetermined grid pattern, and the first, second, and third lenses and the additional lenses forming an array of lenses of the predetermined grid pattern.
19 . The backlight module of claim 18 , wherein the array of lenses is made by a molding method.
20 . The backlight module of claim 11 , wherein a distance between the first spot and the substrate is smaller than 6 millimeters.