CN210038398U - Direct type backlight module, liquid crystal display screen and television - Google Patents

Abstract

The utility model discloses a straight following formula backlight unit, liquid crystal display and TV, wherein, straight following formula backlight unit includes a plurality of LED lamps and sets up the diffuser plate in LED lamp top, and every LED lamp below all is provided with a fresnel reflector, and sets up the center department that the LED lamp is located corresponding fresnel reflector. The utility model provides an LED light source mutual interference influence regional accuse light effect's problem among the current HDR technique.

Description

Direct type backlight module, liquid crystal display screen and television

Technical Field

The utility model relates to a display screen technical field especially relates to a straight following formula backlight unit, liquid crystal display and TV.

Background

At present, HDR and Local Dimming technologies realize regional light control through an L-partition LED light source, and realize brighter parts and deeper parts in a picture, so that the dynamic contrast of the picture is improved, and a higher picture quality brightness range, brighter picture colors and clearer picture details are brought to a user. The HDR technology has become a market for various display manufacturers, and the interference between the LED light sources in the HDR technology affects the local light control effect to some extent.

Currently, HDR technology is mainly a direct-lit model due to the lateral LGP lighting limitation. Specifically, each LED light source is controlled, and the current of the LED is controlled according to signal indication, so that the brightness and the on-off control are realized. However, because the LEDs have a light emitting angle of-60 °, when the HDR function is turned on, the light between two adjacent LEDs is easily interfered, i.e., the brightness of the area is affected by the switches of the adjacent LEDs. Like this here picture be profound night, and the adjacent picture is the twinkling stars, and the LED of the corresponding region in night is closed under the HDR effect, but adjacent department because the twinkling stars, the LED that should be corresponding in this department can increase the electric current, increases luminance promptly, and because the light angle is great, the light of stars can disperse to should be the corresponding region in night, leads to the dark night place can not show profound night picture under the ideal HDR state.

Accordingly, the prior art is yet to be improved and developed.

SUMMERY OF THE UTILITY MODEL

The to-be-solved technical problem of the utility model lies in, to prior art's above-mentioned defect, provide a straight following formula backlight unit, liquid crystal display and TV, aim at solving the problem that LED light source mutual interference influences regional accuse light effect in the current HDR technique.

The utility model provides a technical scheme that technical problem adopted as follows:

the utility model provides a straight following formula backlight unit, wherein, includes a plurality of LED lamps and sets up the diffuser plate in LED lamp top, every LED lamp below all is provided with a fresnel reflector, and every LED lamp is located the center department that corresponds fresnel reflector.

The direct type backlight module is characterized in that one surface, facing the LED lamp, of the Fresnel reflector is a Fresnel reflection surface, and the surface, far away from the LED lamp, of the Fresnel reflector is a plane.

The direct type backlight module is characterized in that the Fresnel reflection surface comprises a plurality of circular arc spiral surfaces which are sequentially sleeved at equal intervals from small to large.

The direct type backlight module is characterized in that the LED lamp is arranged at the focus of the corresponding Fresnel reflection surface.

The direct type backlight module is characterized in that the thickness of the Fresnel reflector is 1-2 mm.

The direct type backlight module is characterized in that the Fresnel reflector is made of PMMA or PET optical base materials.

The direct type backlight module is characterized in that the LED lamps are arranged in an array.

The direct type backlight module is characterized in that a plurality of Fresnel reflectors are spliced into a whole.

A liquid crystal display screen comprises the direct type backlight module.

A television comprising a liquid crystal display as described above.

Has the advantages that: the utility model discloses a fresnel reflector utilizes fresnel reflector convergent light's effect to reduce the narrow light angle as the reflector plate of LED lamp among the straight following formula backlight unit, makes light all tend to vertically back-fire with the diffuser plate, reduces the mutual interference between the LED light source, has improved HDR local regulation effect in a poor light, improves accuse light precision greatly, has solved the problem that LED light source mutual interference influences regional accuse light effect among the current HDR technique.

Drawings

FIG. 1 is a schematic diagram of the principle of concave mirror light gathering;

FIG. 2 is a schematic structural diagram of a direct-type backlight module of the present invention;

FIG. 3 is a side view and a projection effect diagram of the Fresnel reflector according to the present invention;

fig. 4 is a front view of the fresnel reflector of the present invention;

FIG. 5 is a schematic view illustrating the light-gathering effect of the direct-type backlight module of the present invention;

fig. 6 is a schematic structural view of the fresnel reflectors of the present invention after being manufactured into a single piece.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention clearer and clearer, the present invention will be described in further detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

The concave mirror can converge light, for example, the light emitted by the bulb is converged by using the convergence effect of the concave reflector at the front section of the flashlight, as shown in fig. 1, the light tends to be collimated, so that the emitted light beam is high-bright and the light path converges.

Straight following formula backlight unit, as shown in fig. 2~5, including a plurality of LED lamps 10 and the diffuser plate 20 of setting in LED lamp 10 top, every LED lamp 10 below all is provided with a fresnel reflector 30, and every LED lamp 10 is located the center department that corresponds fresnel reflector 30. Fresnel reflector 30 utilize concave mirror convergence principle promptly, utilize fresnel reflector 30 convergent light, narrow light angle, make it tend to jet out with diffuser plate 20 vertically direction to reduce the mutual interference between the LED light source.

Fresnel reflector 30 specifically is a concave mirror split circle of circle ring structure and through the Fourier transform put a face again, form a class planar concave mirror, fresnel ring reflector promptly. As shown in fig. 3, a fresnel reflection surface 31 is formed on a surface of the fresnel reflector 30 facing the LED lamp 10, that is, a plurality of tiny arc reflection surfaces are symmetrically disposed on the fresnel reflection surface, and these arc reflection surfaces can be projected into a larger arc surface in a backlight side direction (that is, in a module light emitting direction), so that the fresnel reflector has the same function as a concave mirror, and the light rays directly irradiated from the LED lamp onto the reflector and reflected onto the reflector via a diffusion plate are converged, and the light emitting angle is changed, so that the light rays are all emitted in a reverse direction perpendicular to the reflection sheet, thereby reducing the light emitting interference between each LED lamp, and realizing precise light control. Preferably, the surface of the fresnel reflector far away from the LED lamp is provided with a flat surface 32, so as to further ensure the vertical reflection effect and reduce the overall thickness of the reflector.

Preferably, as shown in fig. 4, in the direct-type backlight module, the fresnel reflection surface 31 is in a radial circular ring shape, that is, the fresnel reflection surface includes a plurality of circular arc spiral surfaces sequentially sleeved from small to large at equal intervals (that is, the intervals between adjacent circular rings are the same), each circular arc spiral surface is a reflection surface, and the fresnel reflection surfaces can be joined into a standard concave mirror 100 by projection. Further, each LED lamp 10 is disposed at a focus of the corresponding fresnel reflection surface 31, so that light directly irradiated onto the reflector through the LED lamp 10 is emitted in a direction perpendicular to the diffusion plate 20, thereby achieving precise vertical partitioning. As shown in fig. 5 (arrows in the figure indicate inertia), after the fresnel reflector 30 is used, due to the action of the concave mirror to converge light, the angle of light rays which originally hit between two LEDs is reduced, that is, mutual interference is reduced, the HDR local backlight adjustment effect is improved, and the light control precision is greatly improved.

The fresnel reflector 30 can be made of PMMA or PET as an optical substrate, and is a common optical material with high cost performance. The distance and depth of the rings of the fresnel reflector 30 can be adjusted according to the specific LED emitting angle and distance. The manufacturing process of the reflector is similar to that of the existing optical film prism lens, the shape is etched by adopting a metal mold, and then the PET substrate is printed by using the etched metal roller, in the direct type backlight module, the thickness of the Fresnel reflector 30 is controlled to be 1-2 mm, the whole thickness of the module is not influenced, and the design requirement of an ultrathin television can be met.

Additionally, in the utility model discloses in LED lamp 10 can be the array and arrange, correspondingly, a plurality of fresnel reflectors 30 can be independent a slice piece is constituteed, also can be according to the number of LED lamp make a whole piece embolia the LED array, as shown in fig. 6.

Based on above-mentioned straight following formula backlight unit, the utility model discloses still provide a liquid crystal display, wherein, include as above straight following formula backlight unit.

The utility model also provides a TV, wherein, include as above liquid crystal display.

To sum up, the utility model provides a straight following formula backlight unit, liquid crystal display and TV adopts the fresnel reflector as the reflector plate of LED lamp among the straight following formula backlight unit, utilizes the effect of fresnel reflector convergent light to reduce the light angle, makes light all tend to vertically back-emitting with the diffuser plate, reduces the mutual interference between the LED light source, has improved HDR local backlight adjusting effect, improves the problem that the LED light source influences regional accuse light effect of mutual interference each other among the current HDR technique greatly and has been solved to accuse light precision.

It is to be understood that the invention is not limited to the above-described embodiments, and that modifications and variations may be made by those skilled in the art in light of the above teachings, and all such modifications and variations are intended to be included within the scope of the invention as defined in the appended claims.

Claims (7)

1. A direct type backlight module is characterized by comprising a plurality of LED lamps and a diffusion plate arranged above the LED lamps, wherein a Fresnel reflector is arranged below each LED lamp, and each LED lamp is positioned at the center of the corresponding Fresnel reflector; one surface of the Fresnel reflector facing the LED lamp is a Fresnel reflection surface, and the other surface of the Fresnel reflector far away from the LED lamp is a plane; the Fresnel reflection surface comprises a plurality of arc spiral surfaces which are sequentially sleeved at equal intervals from small to large; the LED lamp is arranged at the focus of the corresponding Fresnel reflection surface.

2. The direct type backlight module as claimed in claim 1, wherein the Fresnel reflector has a thickness of 1-2 mm.

3. The direct type backlight module as claimed in claim 1, wherein the Fresnel reflector is made of PMMA or PET optical substrate.

4. The direct type backlight module as claimed in claim 1, wherein the LED lamps are arranged in an array.

5. The direct type backlight module according to claim 4, wherein the Fresnel reflectors are integrally joined.

6. A liquid crystal display panel, comprising the direct type backlight module according to any one of claims 1 to 5.

7. A television comprising the liquid crystal display of claim 6.

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