TWI533189B - Touch panel - Google Patents

Description

Touch screen

The present invention relates to a touch screen, and more particularly to a touch screen capable of reducing the reflectivity of an OLED panel.

At present, the visibility of the mobile phone panel under strong light is relatively poor, mainly due to the strong reflection of the surface of the panel on sunlight. Compared with the LCD panel, the brightness of the OLED panel is low, and in order to improve the contrast under strong light, the panel needs to have a lower reflectance. As shown in FIG. 1 , the main modules of the OLED panel include a touch panel 2 (Touch Panel, TP for short), a polarizer 22 (Polarizer, POL for short), and an Organic Light Emitting Diode (OLED). The polarizer 22 can absorb the ambient light reflected by the surface of the luminescent layer 23 (OLED device), so the reflectivity of the panel is mainly determined by the reflectivity of the touch screen 2 (TP) to the external light and the polarization of the polarizer 22 (POL). . The reflection of the external light by the touch screen 2 is partially caused by the capacitance sensing circuit layer 21 included in the module. The two sides of the capacitive sensing circuit layer are coated with an optical transparent adhesive 25.

Currently widely used TP types mainly include GG2, GG, OGS, GFF, G1F, GF2, GF1, among which GG2, GG, GFF, GF2, GF1 are constructed by means of bonding, that is, using optical glue (Optical Clear) Adhesive (OCA) attaches a film on which a capacitive sensing circuit is vapor-deposited to a cover glass 24. The module of the conventional OLED panel is attached and aligned with POL and TP on the OLED device luminescent layer 23 of the package.

With the above structure, the internal capacitance sensing circuit structure of the TP will reflect a certain amount of incident ambient light, and the reflected light is about 1.5%, which causes the contrast of the panel under ambient light to decrease, which occupies a very large portion of the panel reflectance. The high ratio, reducing the reflection of this part can effectively improve the visibility of the panel under strong light.

In view of this, the inventors have conceived and studied more deeply, and finally invented a touch screen.

The technical problem to be solved by the present invention is to provide a touch screen capable of effectively reducing the reflection of external light by the OLED panel and improving the contrast and visibility of the panel under strong light.

In order to achieve the above technical effects, the present invention discloses a touch screen that is attached to an OLED panel. The touch screen includes a capacitive sensing circuit layer and a cover encapsulated on the capacitive sensing circuit layer. The plate glass is provided with a polarizer between the capacitor sensing circuit layer and the cover glass.

According to a further improvement of the present invention, the cover glass is adhered to the polarizer through an optically transparent adhesive.

A further improvement of the present invention is that the polarizer is a circular polarizer comprising a linear polarizing plate and a quarter wave plate, and the lower surface of the polarizer is attached An adhesive layer is adhered to the capacitive sensing circuit layer through the adhesive layer.

A further improvement of the present invention is that the touch screen is attached to the OLED panel through an optical transparent adhesive.

The invention adopts the above technical solutions, and has the following beneficial effects: by inserting a polarizer between the capacitive sensing circuit layer of the touch screen and the cover glass, the incident light caused by the capacitive sensing circuit layer can be effectively absorbed. The reflection reduces the reflection of the OLED panel on external light and improves the contrast and visibility of the panel under strong light.

The present invention has been described in connection with the preferred embodiments of the present invention in accordance with the accompanying drawings.

[study]

2‧‧‧Touch screen

21‧‧‧Capacitive sensing circuit layer

22‧‧‧ polarizer

23‧‧‧Lighting layer

24‧‧‧ Cover glass

25‧‧‧Optical transparent adhesive

〔this invention〕

1‧‧‧Touch screen

11‧‧‧OLED panel

12‧‧‧Capacitive sensing circuit layer

13‧‧‧ polarizer

130‧‧‧Adhesive layer

131‧‧‧Line polarizer

132‧‧‧1/4 wave plate

133‧‧‧HC-TAC

134‧‧‧TAC

135‧‧‧Separable layer

14‧‧‧ Cover glass

15‧‧‧Optical transparent adhesive

L‧‧‧Light

N‧‧‧ optical axis

FIG. 1 is a schematic view of a conventional OLED panel module bonding structure.

2 is a schematic view of a bonding structure of an OLED panel module of the present invention.

Fig. 3 is a schematic structural view of a polarizer.

4 is a schematic diagram of a polarizer that absorbs reflected light.

Before the present invention is described in detail, it is noted that in the following description, similar elements are denoted by the same reference numerals.

In order to enable your review committee to have a better understanding and understanding of the purpose, features and effects of the present invention, please follow the following paragraphs. Ming] detailed as follows:

As shown in FIG. 2, the touch screen 1 is attached to the OLED panel 11. The touch screen 1 includes a capacitive sensing circuit layer 12 and is packaged in the capacitive sensing circuit layer. The cover glass 14 on the 12, wherein a polarizing plate 13 is disposed between the capacitive sensing circuit layer 12 and the cover glass 14. The cover glass 14 is bonded to the polarizer 13 through the optically transparent adhesive 15. The touch screen 1 is attached to the OLED panel 11 through the optical transparent adhesive 15 .

The polarizer 13 (Polarizer) is a circular polarizer comprising a linear polarizing plate 131 and a 1/4 wave plate 132. The structure is as shown in FIG. 3, and the upper surface and the lower surface of the linear polarizing film 131 are respectively combined. The HC-TAC 133 and a TAC 134 have an adhesive layer 130 attached to the upper surface and the lower surface of the 1/4 wave plate 132, and a detachable layer 135 is disposed under the adhesive layer 130 on the lower surface. The lower surface adhesive layer 130 and the detachable layer 135 are attached to the upper surface of the capacitive sensing circuit layer 12 for absorbing the reflection of incident light caused by the internal circuit of the capacitive sensing circuit layer 12. Referring to FIG. 4, the principle of the polarizer 13 absorbing reflected light is as follows:

A quarter-wave plate is a birefringent single crystal sheet having a certain thickness. When the light L is incident at the normal direction, the phase difference between the ordinary light (o light) and the extraordinary light (e light) is equal to π/2 or an odd multiple thereof, such a wafer is called a quarter wave plate or a quarter wave plate. When the linearly polarized light is incident perpendicular to the 1/4 wave plate 132, and the polarization of the light L and the optical axis of the mica are N-sided (vertical natural When the cleavage plane is θ=45°, the emitted light is circularly polarized light. After the circularly polarized light is reflected by the internal circuit of the capacitive sensing circuit layer 12, it has a π phase retardation, so the rotation direction of the circular polarization changes, and then the quarter-wave plate becomes a linearly polarized light whose polarization direction is perpendicular to the polarization direction of the linear polarizing plate. Therefore, the reflected light is absorbed by the polarizing plate and does not exit from the panel. Therefore, the polarizer POL is placed on the capacitor sensing circuit layer 12, so that the reflection of the incident light caused by the TP internal capacitance sensing circuit layer 12 is absorbed by the polarizer POL, which can effectively reduce the reflection of the OLED panel on external light and improve the panel. Contrast and visibility under light. The upper surface of the polarizer 13 is further bonded to the cover glass 14 through the optically transparent adhesive 15.

The present invention has been described in detail above with reference to the embodiments of the drawings, and various modifications of the invention can be made by those skilled in the art in light of the above description. Therefore, some of the details of the embodiments are not to be construed as limiting the scope of the invention, which is defined by the appended claims.

From the above, it is known that the present invention truly conforms to "industrial availability," "novelty," and "progressiveness", and submits an invention patent application in accordance with the law, praying for review and early granting of a patent, and it is truly sensible.

1‧‧‧Touch screen

11‧‧‧OLED panel

12‧‧‧Capacitive sensing circuit layer

13‧‧‧ polarizer

14‧‧‧ Cover glass

15‧‧‧Optical transparent adhesive

Claims (3)

A touch screen is attached to an OLED panel, the touch screen includes: a capacitive sensing circuit layer and a cover glass packaged on the capacitive sensing circuit layer, the capacitive sensing circuit layer and the cover A polarizer is disposed between the plate glass, and the polarizer is a circular polarizer comprising a linear polarizing plate and a 1/4 wave plate. The polarizing film has an adhesive layer attached to the lower surface thereof and is adhered through the adhesive layer. On the capacitive sensing circuit layer. The touch screen of claim 1, wherein the cover glass is adhered to the polarizer through an optical transparent adhesive. The touch screen of claim 1, wherein the touch screen is attached to the OLED panel through an optical transparent adhesive.