CN215340632U

CN215340632U - Side light source luminescent plate

Info

Publication number: CN215340632U
Application number: CN202121708162.2U
Authority: CN
Inventors: 吕岳敏; 余荣; 杨烨; 常碧波
Original assignee: Shantou Goworld Display Plant Ii Co ltd; Shantou Goworld Display Technology Co Ltd
Current assignee: Shantou Goworld Display Plant Ii Co ltd; Shantou Goworld Display Technology Co Ltd
Priority date: 2021-07-27
Filing date: 2021-07-27
Publication date: 2021-12-28
Anticipated expiration: 2031-07-27

Abstract

A side light source luminescent plate comprises a scattering plate and an LED lamp group used as a light source, wherein the scattering plate comprises a first transparent plate, a second transparent plate and a liquid crystal layer clamped between the first transparent plate and the second transparent plate, the scattering plate is provided with a first side edge formed by aligning the edges of the first transparent plate and the second transparent plate, and the liquid crystal layer is formed by polymer dispersed liquid crystal capable of changing light scattering property under the action of an electric field; the inner surfaces of the first and second transparent plates are respectively provided with a first and a second electrodes, the first and the second electrodes are at least partially overlapped to form an electrode overlapping region, and voltage can be applied to generate an electric field in the electrode overlapping region so as to change the light scattering property of the liquid crystal layer; the LED lamp group comprises a plurality of LEDs which are arranged on the first side edge and face the scattering plate, the light emitted by the LEDs can be transmitted in the plate body of the scattering plate, and the light can be scattered out of the light-emitting plate according to the light scattering performance of the electrode overlapping area. The light emitting area of such a light emitting panel has a dynamically variable character.

Description

Side light source luminescent plate

Technical Field

The utility model relates to a light-emitting plate, in particular to a light-emitting plate with a side light source, and belongs to the technical field of light-emitting devices.

Background

The side light source light emitting panel generally includes a reflection plate for reflecting light emitted from a light source (e.g., LED) to the front side thereof to form a planar light emitting region, and a light source (e.g., LED) disposed at a side thereof.

The dynamic contrast lcd is generally implemented by using a backlight with a dynamically variable light emitting area (local-dimming), and the dynamic contrast lcd is matched with display contents by controlling the brightness of the backlight in different areas, so as to achieve the purpose of improving the contrast. However, such backlights with dynamically variable light emitting areas typically require different LEDs to be placed on the back of the light emitting panel rather than on the sides, and their thickness is difficult to reduce.

The luminous area of the luminous plate with the side light source is fixed, and when the luminous plate is used as the backlight of a liquid crystal display, the function of dynamic contrast cannot be realized. In addition, the light emitting panel with the side light source cannot be used alone as a display to show simple information.

SUMMERY OF THE UTILITY MODEL

The utility model aims to provide a side-mounted light source luminescent plate, the luminous area of which is dynamically variable. The adopted technical scheme is as follows:

a side light source luminescent plate is characterized in that:

the LED lamp group comprises a scattering plate and an LED lamp group serving as a light source, wherein the scattering plate comprises a first transparent plate, a second transparent plate and a liquid crystal layer clamped between the first transparent plate and the second transparent plate, the scattering plate is provided with a first side edge formed by aligning the edges of the first transparent plate and the second transparent plate, and the liquid crystal layer is composed of polymer dispersed liquid crystal capable of changing light scattering property under the action of an electric field;

the inner surfaces of the first transparent plate and the second transparent plate are respectively provided with a first electrode and a second electrode, the first electrode and the second electrode are at least partially overlapped to form an electrode overlapping region, and voltage can be applied to generate an electric field in the electrode overlapping region so as to change the light scattering property of a liquid crystal layer of the liquid crystal display;

the LED lamp set comprises a plurality of LEDs which are arranged on the first side edge and face the scattering plate, the light emitted by the LEDs can be transmitted in the plate body of the scattering plate, and the light can be scattered out of the light-emitting plate according to the light scattering property of the electrode overlapping area.

Specifically, the first and second transparent plates may be transparent glass substrates or plastic plates (such as PET and PI plastic films) with a thickness of 0.2mm to 3.0mm, or composite plates composed of glass plates and plastic plates, preferably, the first and second transparent plates have a thickness of 1.0mm to 3.0mm, and the greater thickness of the first and second transparent plates is more convenient for lateral incidence of LED light emission. The first and second transparent plates are generally bonded together by a certain frame glue to form the scattering plate. Generally, the first side is a side of the diffusion plate where the first and second transparent plates are aligned with each other, and the LED lamp set is disposed on the first side so that the LED emits light to enter the diffusion plate. The first side may be one, two or three sides of the light diffusion plate, and in addition, the light diffusion plate generally needs to have at least one second side, and at the second side, the first and second transparent plates are staggered to expose the first and second transparent electrodes for connecting with an external circuit.

The first and second electrodes may be transparent conductive films, such as ITO (indium tin oxide) and AZO (zinc aluminum oxide) films, respectively coated on the inner surfaces (surfaces near the liquid crystal layer) of the first and second transparent plates and patterned (e.g., photo-etched).

Generally, there are a plurality of first and second electrodes to form a plurality of electrode overlapping regions. The electrode overlap region may be a plurality of regions which are independent of each other and have a patterned profile, whereby the light-emitting panel can represent simple information according to whether these regions are extinguished (no light is scattered) or lit (light is scattered). The electrode overlapping region may also be a square region constituting an array, whereby the light emitting panel is expected to be a dynamic backlight of a liquid crystal display to achieve a display effect of dynamic contrast.

In order to control the scattering state of the overlapping regions of the different electrodes, the light-emitting panel may be driven by a driving method of a passive matrix LCD, specifically: when the electrode overlapping regions are independent from each other, the static driving mode of the LCD can be adopted for driving (suitable for the situation that the electrode overlapping regions are less); when the electrode overlapping area is formed by the crossing of a plurality of groups of first and second electrodes, the driving can be performed by using the dynamic driving method of the LCD (suitable for the case of more electrode overlapping areas).

The liquid crystal layer is a Polymer Dispersed Liquid Crystal (PDLC), which is generally a liquid crystal structure in which liquid crystal in a fluid state is dispersed in a solid polymer, and the scattering property of the PDLC for light may be changed under the action of an electric field, for example: it can be designed to be a turbid scattering state in the natural state (zero or low electric field) and a clear transparent state with an applied electric field; or conversely, a clear transparent state in the natural state and a turbid scattering state in the state of an applied electric field. Generally, a spacer (e.g., spacer balls) is disposed between the first and second transparent plates to maintain the thickness of the liquid crystal layer (e.g., 4 μm to 40 μm) so that the scattering properties are uniform. During manufacturing, the uncured light-cured polymer and the liquid crystal can be fully mixed, then the mixture is arranged between the first transparent plate and the second transparent plate in a pouring, coating and other modes, and finally ultraviolet light is irradiated to cure the polymer, so that the required liquid crystal layer and scattering plate structure can be obtained. Preferably, in the polymer dispersed liquid crystal, the solid polymer is a liquid crystal polymer having an alignment effect on liquid crystal, and the liquid crystal layer can be designed to be thinner (<8 μm) due to the alignment effect on the liquid crystal, so that the liquid crystal layer has low driving voltage and faster response, and can be matched with a liquid crystal display to achieve the effect of dynamic contrast.

Thus, when the scattering plate is connected with an external drive, the external drive applies a drive voltage to the first and second electrodes to form an electric field in the overlapping region, and the electric field can change the scattering property of the liquid crystal layer.

The LED lamp group comprises a plurality of LEDs which are arranged on the first side edge and face the scattering plate, the light emitted by the LEDs can be sufficiently irradiated into the scattering plate, the light of the LEDs is generally reflected back and forth on the front plate body surface and the rear plate body surface of the scattering plate, when the light meets the overlapping area and is in a scattering state, the light is scattered in the overlapping area, and part of the light is emitted from the front surface of the overlapping area to form a planar light emitting area.

In a preferred aspect of the present invention, the LED light group is an LED light bar attached along a first side edge. Preferably, the height of the LED lamp is smaller than the thickness of the diffusion plate so that the light thereof is completely inputted into the inside of the diffusion plate. Preferably, the LED is an LED bead provided with a condensing lens, and light emitted by the LED bead is condensed in a direction toward the diffuser plate, so that the utilization rate of the light emitted by the LED bead can be improved.

In a preferred aspect of the present invention, a rear reflection layer is provided on a rear side of the diffusion plate. The rear reflecting layer can be a mirror reflecting film adhered to the rear side of the scattering plate, or can be a reflecting coating directly plated on the rear side surface of the scattering plate, such as a silver coating and an aluminum coating.

In a preferred embodiment of the present invention, the front side of the scattering plate may be provided with a front reflective layer, which is a semi-transparent reflective film layer, and specifically, the front reflective layer may be a metal film (such as a silver film or an aluminum film) with a thickness of less than 5nm, or an enhanced reflective film with a refractive index higher than that of the first transparent plate, and an enhanced reflective film system formed by alternately arranging a plurality of media with different refractive indexes.

In a preferred embodiment of the present invention, the light emitting plate further includes a spacer plate, the spacer plate is a transparent plate disposed in front of the diffuser plate, and an air layer is present between the spacer plate and the diffuser plate. Therefore, the outer surface of the scattering plate can be ensured to be an air interface, and the first transparent plate and the air layer have larger refractive index difference, so that the light of the LED can be further ensured to be transmitted in the scattering plate.

Therefore, compared with the existing side light source light-emitting plate, the light-emitting plate provided by the utility model has the characteristic that the light-emitting dynamics of different areas are variable, can be used as a display to express simple information, and is expected to be used as dynamic backlight to be applied to a liquid crystal display to realize the effect of dynamic contrast.

The technical solution of the present invention is further explained by the accompanying drawings and the specific embodiments.

Drawings

Fig. 1 is a schematic perspective view of a light-emitting panel according to a first embodiment;

fig. 2 is a schematic plan view of a light-emitting panel according to the first embodiment;

fig. 3 is a schematic cross-sectional view of a light-emitting panel according to an embodiment and its light guiding and scattering structures;

FIG. 4 is a schematic diagram of a liquid crystal layer of the light-emitting panel according to the first embodiment;

FIG. 5 is a schematic view of a liquid crystal layer of a light-emitting panel according to a first embodiment in a transparent state;

FIG. 6 is a schematic diagram of a liquid crystal layer of the light-emitting panel according to the first embodiment in a scattering state;

fig. 7 is a schematic view of a light-emitting panel according to a first embodiment with front and rear reflective layers;

fig. 8 is a schematic cross-sectional view of a light-emitting panel according to a second embodiment;

fig. 9 is a schematic plan view of the first and second electrodes of the light-emitting panel of the third embodiment.

Detailed Description

Example one

As shown in fig. 1-4, the light-emitting panel 100 includes a diffusion panel 10 and an LED lamp set 20.

The diffusion plate 10 is formed by sandwiching a liquid crystal layer 13 between first and second

transparent plates

11 and 12.

The first and second

transparent plates

11 and 12 are transparent glass substrates having a thickness of 1.1mm, and are adhered to each other by a rubber ring 14, a plurality of first and

second electrodes

111 and 121 are respectively provided on inner surfaces of the first and second

transparent plates

11 and 12, the first and

second electrodes

111 and 121 are formed of patterned (photo-etched) ITO films, the first and

second electrodes

111 and 121 cross each other to form a plurality of electrode overlapping regions 14, and the electrode overlapping regions 14 are a plurality of square regions forming an array.

At the upper side 151 (first side) and the right side 152, the first and second

transparent plates

11, 12 are aligned with each other, and at the left side 153 and the lower side 154 (both second sides), the first and second

transparent plates

11, 12 are staggered to expose the external terminals of the first and

second electrodes

111, 121, so that the first and

second electrodes

111, 121 can be externally driven (external driving is not shown).

As shown in fig. 4 to 6, the liquid crystal layer 13 is sandwiched between the first and second

transparent plates

11 and 12, sealed by a rubber gasket 14, and kept at a thickness of about 6 μm by spacer balls (not shown). The liquid crystal layer 13 includes a solid liquid crystal polymer 131 and a liquid crystal 132, which are mixed sufficiently, and the liquid crystal polymer 131 has an alignment effect on the liquid crystal 132, and the liquid crystal can be blended to have a consistent alignment and birefringence with the liquid crystal 132 in a natural state, so that the liquid crystal layer 13 is in a clear and transparent state. In each electrode overlapping region 14, when a sufficient voltage is applied between the first and

second electrodes

111 and 121, the liquid crystal layer 13 becomes a cloudy scattering state due to the non-uniform orientation of the mobile state liquid crystal 132 and the liquid crystal polymer 131.

As shown in fig. 1-3, the LED lamp set 20 is an LED lamp strip attached to the upper side 151 of the diffuser plate 10, and includes a plurality of LED lamp beads 21 uniformly distributed and facing the diffuser plate 10, the size of the LED lamp beads 21 is smaller than 2.2mm and is provided with a condensing lens, the light 211 is input into the diffuser plate 10 from the upper side 151, and is reflected back and forth between the plate surfaces of the diffuser plate 10 (especially, the outer surfaces of the first and second transparent plates 11 and 12) and transmitted inside the diffuser plate 10, so that the diffuser plate 10 itself, i.e., a light guide plate, is diffused out of the light emitting plate 100 according to the light scattering property of the electrode overlapping region 14.

As shown in fig. 7, in order to further increase the light guiding performance of the diffusion plate 10, the rear side surface of the diffusion plate 10 is further provided with a rear reflection layer 16, which may be a mirror film attached to the rear side of the diffusion plate 10, or a silver film or an aluminum film directly plated on the rear side surface of the second transparent plate 12. The front side of the diffuser plate 10 may also be provided with a front reflective layer 17, which may be a semi-transparent and semi-reflective silver film or aluminum film with a thickness of less than 5nm, or a reflection increasing film system formed by alternating multiple layers of media with different refractive indexes.

The operation of the light emitting panel 100 generally comprises: the LEDs of the LED lamp group 20 are turned on, and light emitted from the LEDs is input into the diffusion plate 10 from the upper side 151 and is conducted inside the diffusion plate 10. A driving signal (referred to as the conventional driving of the passive matrix LCD) is applied to the first and

second electrodes

111 and 121 to control the scattering state (or transparent state) of the liquid crystal layer 13 in the electrode overlapping region 14, and the liquid crystal layer 13 in the scattering state scatters light propagating inside the scattering plate 10 to form a light emitting region. The light emitting area of the light emitting panel 100 is dynamically variable, and thus is expected to be a dynamic backlight of a liquid crystal display, which itself can perform simple information display.

Example two

As shown in fig. 8, in addition to the first embodiment, in order to further increase the light guiding performance of the diffusion plate 10, a glass lens 18 as a spacer is added in front of the diffusion plate 10, thereby constituting a second embodiment of the present invention. The glass lens 18 and the diffusion plate 10 are bonded and fixed through the frame, and an air layer 19 is kept between the glass lens and the diffusion plate 10, so that the outer surface of the diffusion plate 10 can be ensured to be an air interface, the first transparent plate 11 and the air layer 19 have large refractive index difference, reflection and transmission of light emitted by the LED in the diffusion plate 10 can be further ensured, and the final emergent brightness is increased.

EXAMPLE III

As shown in fig. 9, on the basis of the first embodiment, the electrode overlapping area 14 is changed to an icon or a pen segment (e.g., a graph of "a" or "B"), thereby forming a third embodiment of the present invention. The light emitting panel of the third embodiment can be used alone as a display for simple information presentation. The electrode overlapping region 14 is formed by overlapping different second electrodes with a common first electrode, and thus, the driving thereof may be performed by a static driving method of a general LCD.

In addition, it should be noted that the names of the parts and the like of the embodiments described in the present specification may be different, and the equivalent or simple change of the structure, the characteristics and the principle described in the present patent idea is included in the protection scope of the present patent. Various modifications, additions and substitutions for the specific embodiments described may be made by those skilled in the art without departing from the scope of the utility model as defined in the accompanying claims.

Claims

1. A side light source luminescent plate is characterized in that:

2. The light-emitting panel of claim 1, wherein: the thickness of the first transparent plate and the second transparent plate is 1.0-3.0 mm.

3. The light-emitting panel of claim 1, wherein: the electrode overlapping area is a plurality of mutually independent areas with graphic outlines.

4. The light-emitting panel of claim 1, wherein: the electrode overlap region is a square region constituting an array.

5. The light-emitting panel of claim 1, wherein: in the polymer dispersed liquid crystal, the solid polymer is a liquid crystal polymer having an alignment effect on liquid crystal.

6. The light-emitting panel of claim 1, wherein: the LED lamp set comprises a plurality of LEDs with the height smaller than the thickness of the scattering plate.

7. The light-emitting panel of claim 6, wherein: the LED is an LED lamp bead provided with a condensing lens.

8. The light-emitting panel of claim 1, wherein: and a rear reflecting layer is arranged on the rear side of the scattering plate.

9. The light-emitting panel of claim 1, wherein: the front side surface of the scattering plate is provided with a front reflection layer, and the front reflection layer is a semi-transparent semi-reflection film layer.

10. The light-emitting panel of claim 1, wherein: the luminescent plate still includes the division board, the division board is the transparent plate, and it sets up the diffuser plate front side, there is the air bed between division board and the diffuser plate.