TWI600950B - Front light plate and memory lcd thereof - Google Patents

Description

Front light plate and semi-transmissive display device thereof

The present invention relates to the field of display devices, and more particularly to a light panel and a transflective display device thereof that can be applied to a transflective display device.

Most current display devices are non-self-illuminating displays and can be divided into transmissive and reflective. The transmissive display device is configured to use a backlight module as a backlight under the panel to form a display screen, and the reflective display device to form a display screen by reflecting ambient light. In recent years, reflective display devices that use ambient light as a light source have been widely used in portable products due to the popularization of portable products and their requirements for thinness and power saving. However, when the reflective display device is used indoors or in a dark environment, the display quality is greatly degraded, resulting in poor contrast and poor image quality, and the reflective display device is also difficult to design. Therefore, the relevant manufacturers tamper with the semi-transflective display device instead of the reflective display device in order to improve the display quality.

The semi-transflective display device is a display technology that has recently been developed, and has the characteristics of both transmissive and reflective display devices. In the current product, the semi-transmissive display device is generally equipped with a backlight module, so that when the ambient light is strong, the backlight module is not lit, and only the ambient light penetrates the panel to reflect the light, thereby achieving power saving. The effect is to prevent the over-bright condition from affecting the viewing; if the indoor or ambient light is weak, the backlight module is illuminated, and the light source is used as a light source to achieve the display purpose, thereby avoiding the situation that the brightness is too dark.

However, at present, depending on the application requirements of the semi-transflective display device, the structural design still has various changes to be developed, but regardless of the structure of the transflective display device, the ultimate goal is to effectively improve the display performance of the transflective display device. To make it have better use quality, these goals are important development points of relevant manufacturers.

An object of the present invention is to provide a front light panel and a transflective display device thereof, which can meet the light requirements of the transflective display device for display purposes and improve the overall display performance and quality of the display device.

In order to achieve the above object, an embodiment of the present invention provides a front light panel for use in a transflective display device, the transflective display device having a liquid crystal layer having a light incident surface and a light exit surface. a light-emitting surface for receiving light of at least one light source, the light-emitting surface being opposite to the lower surface and vertically adjacent to the light-incident surface, wherein the liquid crystal layer is disposed corresponding to the lower surface, and is characterized by: The front light plate further has a plurality of microstructures disposed on the light-emitting surface, so that light entering from the light-incident surface is formed on the light-emitting surface by a first light pattern and formed on the lower surface by a second light pattern. Light-emitting, and the angle between the main optical axis of the first light type and the reference axis perpendicular to the light-incident surface is between 15 and 25 degrees, and the angle between the main optical axis of the second light type and the reference axis is between 55~ 65 degrees; thereby, the second light pattern provides light to the liquid crystal layer of the transflective display device at an angle of 55 to 65 degrees, and reflects after transmitting a picture information provided by the liquid crystal layer Go to the illuminating surface and avoid traveling by light Small angle to the reference axis directly through the liquid crystal layer. In view of the characteristics of the transflective device, the front plate has the light-emitting state of the first light type and the second light type through the microstructures, so that the liquid crystal layer can accurately obtain the light provided by the front light plate for display purposes.

In one embodiment, the angle of the envelope surface of the first light type at a light intensity of 50% of the maximum light intensity is 20 degrees, that is, the light development state of the second light type is revealed. Can have better display performance.

In another embodiment, the angle of the 50% maximum light intensity envelope surface of the second light type may also be 20 degrees, that is, the light development state of the second light type is exposed to obtain a better display quality.

In an embodiment, the lower surface is coated with an optical glue to be bonded to the liquid crystal layer, and the luminous flux ratio of the first light type and the second light type is 2:8. In addition to bonding the front plate and the liquid crystal layer, the optical glue can also enhance the light energy of the light emitted from the lower surface through the characteristics of guiding light, so that the liquid crystal layer can obtain more sufficient light intensity.

In order to make the front light plate have a better light control effect on the spread angle of the first light type and the second light type and the main light axis, in one embodiment, the microstructures are distributed in a trapezoidal concave shape on the light exit surface. And the angle between the bottom of the microstructure and the sidewall of any of the microstructures is 130 to 150 degrees.

The present invention also discloses a transflective display device, comprising: a light source; a front light plate having a light incident surface, a light exit surface, a lower surface and a plurality of microstructures, the light incident surface for receiving the light Light emitted by the light source, the light emitting surface is disposed opposite to the lower surface and vertically adjacent to the light incident surface, and the microstructures are disposed on the light emitting surface, so that the light enters the front light plate from the light incident surface, respectively The light-emitting surface forms light by a first light type and forms a light on the lower surface by a second light type, and an angle between a main optical axis of the first light type and a reference axis perpendicular to the light-incident surface is between 15~ 25 degrees, the angle between the main optical axis of the second optical type and the reference axis is between 55~ 65 degrees; and a liquid crystal layer corresponding to the lower surface; thereby, the second light pattern provides light to the liquid crystal layer at an angle of 55 to 65 degrees, and is provided by the liquid crystal layer A picture information is reflected to the light exiting surface, thereby avoiding direct penetration of the liquid crystal layer due to the angle between the traveling direction of the light and the reference axis being too small. Thereby, the light-emitting state of the front light plate is adjusted through the microstructures, so that the light irradiated to the liquid crystal layer is relatively straight, and the light can be prevented from penetrating the liquid crystal layer, so that the image cannot be displayed.

Similarly, based on the foregoing embodiment, in another embodiment, the angle of the 50% maximum light intensity envelope surface of the first light type is 20 degrees, that is, the light development state of the first light type is revealed, and the angle is under the foregoing angle. Better display quality is obtained.

Or in another embodiment, the angle of the 50% maximum light intensity envelope surface of the second light type is also 20 degrees, that is, the light development state of the second light type is exposed, and the half angle can be made at the foregoing angle. The reverse display device has better display performance.

In addition, in order to fix the front light plate and the liquid crystal layer, in one embodiment, the lower surface is coated with an optical glue to be bonded to the liquid crystal layer, and the luminous flux ratio of the first light type and the second light type is It is 2:8. In addition to the bonding effect by optical glue, the light energy of the lower surface can be improved by the light guiding property of the optical glue.

In order to make the front light plate have a better control effect on the spread angle of the first light type and the second light type and the main optical axis, in one embodiment, the microstructures are distributed in a trapezoidal concave shape on the light exit surface, and The angle between the bottom of each of the microstructures and the sidewall is 130 to 150 degrees.

In summary, the present invention discloses a front light panel and a semi-transmissive display device thereof, which enables the semi-transflective display device to jump off the structure of the backlight module as a light source, and then utilizes the front light source side. formula. The micro-structures of the light-emitting surface of the front light plate are used to adjust the light-emitting type of the light surface and the lower surface, and the second light type that is relatively collimated prevents the light from directly penetrating the liquid crystal layer. Further, the front plate and the liquid crystal layer can be bonded through the optical adhesive, and the light flux of the optical adhesive is utilized to increase the luminous flux of the lower surface, so that the liquid crystal layer has more sufficient light.

1‧‧‧front plate

10‧‧‧Into the glossy surface

11‧‧‧Glossy

12‧‧‧ Lower surface

13‧‧‧Microstructure

14‧‧‧Optical adhesive

2‧‧‧Half-through anti-display device

20‧‧‧Liquid layer

21‧‧‧Light source

22‧‧‧Face cover

3‧‧‧Tools

L ₁ ‧‧‧First light type

L ₂ ‧‧‧Second light type

A ₁ ‧‧‧ main optical axis

A ₂ ‧‧‧ main optical axis

B‧‧‧reference axis

‧‧‧‧ angle

‧‧‧‧角角

θ ₁ ‧‧‧ 50% maximum light intensity envelope profile angle of the first light type

θ ₂ ‧‧‧50% of the maximum light intensity envelope profile of the second light type

A‧‧‧ angle

B‧‧‧ angle

1 is a perspective exploded view of a transflective device according to a preferred embodiment of the present invention.

Fig. 2 is a side view of a transflective device according to a preferred embodiment of the present invention.

FIG. 3A is a schematic view showing another aspect of microstructure processing according to a preferred embodiment of the present invention.

FIG. 3B is a schematic view showing another aspect of the microstructure of the preferred embodiment of the present invention.

Figure 4 is a side elevational view of a transflective display device in accordance with another embodiment of the preferred embodiment of the present invention.

Figure 5 is a partially exploded view of a transflective device according to another embodiment of the preferred embodiment of the present invention.

At present, the semi-transmissive display device utilizes a backlight module as a reinforcing light source other than ambient light. As described above, the semi-transflective display device has the characteristics of a transmissive and reflective display device, and the inventor of the present invention skips the old technology. The idea is to abandon the use of backlight modules, and the concept of the front light module is applied to the semi-transmissive display device. The front light module has been applied to the reflective display device in the past, and includes the front light plate and the light source and is disposed in front of the display panel. Therefore, in principle, the main light output of the front light plate is directed to the panel as the most important design requirement to have sufficient light intensity. The display panel is reflected on the display panel to form a display screen, and the micro-structure setting can effectively adjust the light-emitting state of the front light panel. Generally, the microstructure is disposed on the surface of the front panel corresponding to the bonding panel to be guided by the microstructure. Most of the light entering the front panel of the light source forms light on the surface, and the remaining portion of the light forms light from the light exiting surface of the surface. At the same time, due to the influence of the microstructure, the light pattern of the light emitted from the surface of the corresponding panel will be more skewed, that is, the angle between the main optical axis of the light type and the normal of the surface is larger, and the light pattern emitted by the light exiting surface is light. It is relatively straightforward, that is, the angle between the main optical axis of the light pattern and the surface normal is small. The foregoing is a front light plate design in an ideal state, but when applied to a semi-transmissive display device, it is found through a reverse optical experiment that, based on the semi-transmissive property, when the light type of the light emitted from the surface of the corresponding panel of the front light plate is too skewed, The light is directly penetrated, and the reflection phenomenon cannot be generated on the panel, resulting in no display. Therefore, when designing a light board before being applied to a trans-display device, unlike the past, the light intensity is not the most important design requirement, but the light-type state must be considered first to prevent direct penetration of the display panel. Happening. Therefore, after constant conceiving and experimenting, the inventors proposed a light panel designed in accordance with the characteristics of the transflective display device, as described below.

Please refer to FIGS. 1 and 2, which are perspective views of a transflective device and a side view of a transflective display device according to a preferred embodiment of the present invention. The present invention discloses a front light panel 1 for use in a half-transflective display device 2, and a transflective display device 2 having a liquid crystal layer 20. The front light panel 1 has a light incident surface 10, a light exiting surface 11 and a lower surface 12, and the light incident surface 10 is configured to receive light from at least one light source 21, and the light source 21 is an LED light strip as an example. The light-emitting surface 11 and the lower surface 12 are disposed opposite each other and are vertically adjacent to the light-incident surface 10, respectively, and the liquid crystal layer 20 is disposed corresponding to the lower surface 12.

The front light plate 1 is characterized in that it has a plurality of microstructures 13 disposed on the light-emitting surface 11 to allow light to enter the light-emitting surface 10 and form a light on the light-emitting surface 11 with a first light pattern L ₁ and the lower surface 12 A second light pattern L ₂ forms light, and an angle α between the main optical axis A _{1 of the} first light pattern L ₁ and a reference axis B of the vertical light incident surface 10 is between 15 and 25 degrees, and the second light pattern L ₂ The angle β between the main optical axis A ₂ and the reference axis B is between 55 and 65 degrees. Thereby, the second light type L ₂ supplies light to the liquid crystal layer 20 of the transflective display device 2 at an angle β between 55 and 65 degrees, and reflects to the light output after carrying one of the screen information provided by the liquid crystal layer 20. The face 11, and further avoiding direct penetration of the liquid crystal layer 20 due to the angle between the direction in which the light travels and the reference axis B are too small. In detail, after the light from the light source 21 enters the front light plate 1 from the light incident surface 10, the second light pattern L ₂ emitted from the lower surface can be adjusted to be enlarged and the reference is affected by the microstructure 13 disposed on the light exit surface 11. The angle β of the axis B, the first light pattern L ₁ emitted from the light exit surface can be adjusted to reduce the angle α with the reference axis B, thereby conforming to the characteristics of the liquid crystal layer. Preferably, in the embodiment, the microstructures 13 are in the form of grooves, and according to the distance from the light-incident surface 10, the layout density is increased from the side of the light-incident surface 10 toward the opposite side. However, this is only a preferred arrangement, and the invention is not limited thereto. And preferably by the first light type L A _{1. 1} of the main optical axis an angle α to the reference axis B line is 20 degrees, the second type optical axis L ₂ of the main axis A ₂ and B reference angle β is 60 degrees, For better reflection.

Type L and the first light and the second light _{pattern. 1} L ₂ 50% of the maximum light intensity cross-sectional size of the angle between the envelope surface, a first optical system may determine the type L type L carry a second optical state ₁₂ i.e. the shape thereof. In the present embodiment, the enveloping surface section angle θ ₁ of the 50% maximum light intensity of the first light type L ₁ is 20 degrees, and the envelope surface section angle θ of the 50% maximum light intensity of the second light type L ₂ is disclosed. ₂ can also be 20 degrees, whereby the transflective device 2 for applying the aforementioned front light plate 1 has better display performance. The first light type L ₁ and the second light type L ₂ shown in FIG. ₂ are only for illustrative purposes, and are not actual light shapes.

Please refer to FIGS. 3A and 3B , which are schematic diagrams and microstructures of another embodiment of the microstructure processing according to a preferred embodiment of the present invention. Furthermore, in order to control the angle of the light pattern and the direction of the main optical axis, in one embodiment, the design microstructure 13 is distributed in a trapezoidal shape on the light exit surface 11 and the angle b between the bottom and the side wall is 130 to 150 degrees, as shown in Figure 3B. From the viewpoint of the processing method, in the present embodiment, the front light plate 1 can be directly processed by the precision tool 3 having an inclination angle of about 50 degrees. As shown in FIG. 3A, the tool 3 is in contact with the light-emitting surface 11 and then cut in a rotating manner, and further on the light-emitting surface. 11 forms a trapezoidal recessed microstructure 13 as shown in Fig. 3B. After the mold is processed and reproduced, the front light plate 1 is further formed to form a trapezoidal concave microstructure 13 and the angle b between the bottom and the side wall is 140 degrees. Of course, depending on the process nuances, for example, the difference in refractive index of the material of the front plate 1 and the difference in the overall module stack are allowed to have an adjustment value of plus or minus ten degrees.

Please refer to FIGS. 4 and 5, which are partially exploded views of a side view of a transflective device and a transflective display device according to another embodiment of the preferred embodiment of the present invention. The front light plate 1 and the liquid crystal layer 20 are disposed on the lower surface 12, and the lower surface 12 is bonded to the liquid crystal layer 20, and the first light type L ₁ and the second light type L _{2 are} disposed. The luminous flux ratio is 2:8. The optical filter 14 can change the total reflection condition of the front light plate 1 to achieve the effect of attracting light, so that the light energy of the light emitted from the lower surface 12 is greater than the light energy emitted by the light exit surface 11 for obtaining the liquid crystal layer 20. Straight light also has enough light intensity. The first light type L ₁ and the second light type L ₂ shown in FIG. 4 are only for illustrative purposes, and are not actual light shapes. In addition, since the front light plate 1 is disposed above the liquid crystal layer 20, a surface cover 22 may be disposed on the side of the light-emitting surface 11 as shown in FIG. 5 to achieve the effect of protecting the front light plate 1. Similarly, in this embodiment, the microstructure 13 is disposed on the light-emitting surface 11 as a trapezoidal shape as described above.

Referring to FIGS. 1 to 5, the present invention also discloses a transflective display device 2 comprising a light source 21, a front light plate 1 and a liquid crystal layer 20. The light source 21 is correspondingly disposed on the light incident surface 10 of the front light plate 1 to provide light to the front light plate 1. The front light plate 1 has a light-incident surface 11 and a lower surface 12 which are respectively adjacent to the light-incident surface 10 and are disposed opposite to each other, and a microstructure 13 is disposed on the light-emitting surface 11 to make the light source 21 light from the light incident surface 10 into the top sheet after 1, respectively, in the first optical surface 11 to form _an L-type light, and the light 12 to the second light L ₂ type formed on the lower surface, and the first light L ₁ of the type main optical axis A ₁ and the vertical reference surface 10 of the B-axis angle α of between 15 and 25 degrees, the second type of light L ₂ of the main axis A ₂ and the angle β between the reference axis B is 55 to 65 degree.

The liquid crystal layer 20 is disposed corresponding to the lower surface 12, whereby the second light pattern L ₂ supplies light toward the liquid crystal layer 20 at an angle of 55-65 degrees, and is reflected to the light-emitting surface 11 after carrying the screen information provided by the liquid crystal layer 20. Therefore, the liquid crystal layer 20 is directly penetrated due to the angle between the traveling direction of the light and the reference axis B being too small to achieve display performance. The remaining detailed technical features are as described above and will not be described again.

Similarly, the herein disclosed transflective display device 2, the first light L ₁ type 50% of the maximum light intensity cross section of the envelope surface angle θ ₁ is 20 degrees and the second light L ₂ type 50% of the maximum light intensity envelope The face cross-sectional angle θ ₂ is 20 degrees, and the above-described transflective display device 2 has a better display effect. In order to control the angle of the light pattern and the direction of the main optical axis, as in the foregoing, in one embodiment, the design microstructure 13 is distributed in a trapezoidal concave shape on the light exit surface 11 and the angle between the bottom and the side wall is b. It is 130~150 degrees. As shown in Figures 3A and 3B. According to the processing method, in the present embodiment, the front light plate 1 can be directly processed by the precision tool 3 having an inclination angle of about 50 degrees. After the tool 3 contacts the light-emitting surface 11, the cutting is performed in a rotational manner, and the microstructure of the trapezoidal depression is formed on the light-emitting surface 11 13. Similarly, after the mold is reprinted, the front plate 1 is further formed, thereby forming the trapezoidal concave microstructure 13 and the angle b between the bottom and the side wall is 140 degrees. Of course, depending on the process nuances, for example, the difference in refractive index of the material of the front plate 1 and the difference in the overall module stack are allowed to have an adjustment value of plus or minus ten degrees.

In addition, as shown in FIG. 4, in order to fix the front light plate 1 and the liquid crystal layer 20 to each other, an optical adhesive 14 is applied to the lower surface 12 to form the liquid crystal layer 20 and the front light plate 1 by adhesive bonding. The optical light 14 is guided by the optical glue 14 to make the light flux ratio of the first light type L ₁ and the second light type L ₂ 2:8, and the light energy emitted by the lower surface 12 is increased, so that the liquid crystal layer 20 can receive enough. The light. As shown in FIG. 5, a surface cover 22 can be disposed on the side of the light-emitting surface 11 to achieve the effect of protecting the front light plate 1.

In summary, since the transflective display device is different from the transmissive and reflective display devices, the adjustment of the light supply requires a lot of tests to know the most suitable structure and mode, and the optical is different. In the general mechanical structure, it is not easy to change or change to make the light smoothly reach the desired state. Therefore, after the inventors studied a large number of test results, it is understood that the conventional application of the light plate to the reflective display device is not applicable. The reason for the half-through anti-display device is then further conceived and repeated optical tests until the technical content as disclosed in the present invention is obtained. The invention discloses a light panel and a semi-transmissive display device thereof, which enable the semi-transflective display device to jump off the structure of the backlight module as a light source, and then use the front light source method to effectively improve the display quality, and utilize the microstructures. Adjusting the light pattern of the front panel and providing it through a more collimated second light type The light is applied to the liquid crystal layer so that the picture information of the liquid crystal layer can be carried and reflected to the light emitting surface, preventing the light from directly penetrating the liquid crystal layer.

However, the above description is only for the preferred embodiment of the present invention, and is not intended to limit the scope of the present invention; therefore, equivalent changes and modifications may be made without departing from the spirit and scope of the invention. Within the scope of the patent of the present invention.

1‧‧‧front plate

10‧‧‧Into the glossy surface

11‧‧‧Glossy

12‧‧‧ Lower surface

13‧‧‧Microstructure

2‧‧‧Half-through anti-display device

20‧‧‧Liquid layer

21‧‧‧Light source

Claims (10)

A front light plate for use in a half-transflective display device, the transflective display device having a liquid crystal layer, the front light plate having a light incident surface, a light exit surface and a lower surface, the light incident surface being configured to receive at least one a light source of the light source, the light emitting surface is opposite to the lower surface and vertically adjacent to the light incident surface, and the liquid crystal layer is disposed corresponding to the lower surface, wherein the front light plate further has a plurality of microstructures, and the light shielding layer is disposed on the plurality of micro structures The light-emitting surface, after the light enters from the light-incident surface, respectively forms a light on the light-emitting surface by a first light pattern and forms a light on the lower surface in a second light pattern, and the main optical axis of the first light type The angle between the main axis of the second light pattern and the reference axis is between 55 and 65 degrees, and the second light type is The angle between 55 and 65 degrees provides light to the liquid crystal layer of the transflective display device, and reflects the image information provided by the liquid crystal layer to reflect the light exiting direction. The angle of the reference axis is too small to directly penetrate the Crystal layer. The light panel of claim 1 is characterized in that the angle of the 50% maximum light intensity envelope surface of the first light type is 20 degrees. The light panel of claim 1 is characterized in that the angle of the 50% maximum light intensity envelope surface of the second light type is 20 degrees. The light plate of the first aspect of the invention, wherein the lower surface is coated with an optical glue to be bonded to the liquid crystal layer, and the luminous flux ratio of the first light type and the second light type is 2:8. . The light plate of the first aspect of the patent application scope, wherein the microstructures are trapezoidal depressions The shape is distributed on the light emitting surface, and the angle between the bottom of any of the microstructures and the sidewall is 130 to 150 degrees. A transflective display device comprising: a light source; a front light plate having a light incident surface, a light exit surface, a lower surface and a plurality of microstructures, wherein the light incident surface is configured to receive light emitted by the light source, the light emitting surface and the light emitting surface The lower surface is oppositely disposed and vertically adjacent to the light incident surface, and the microstructures are disposed on the light emitting surface, so that light entering the front light plate from the light incident surface is formed by a first light pattern on the light emitting surface. Light-emitting and forming a light on the lower surface in a second light pattern, and an angle between a main optical axis of the first light pattern and a reference axis perpendicular to the light-incident surface is between 15 and 25 degrees, and the second light type The angle between the main optical axis and the reference axis is between 55 and 65 degrees; and a liquid crystal layer corresponding to the lower surface; thereby, the second optical pattern faces the liquid crystal at an angle of 55 to 65 degrees The layer provides light and reflects the image information provided by the liquid crystal layer to reflect the light exiting surface, thereby preventing the liquid crystal layer from directly penetrating due to the angle between the traveling direction of the light and the reference axis being too small. The transflective display device of claim 6, wherein the 50% maximum light intensity envelope surface of the first light pattern has an angle of 20 degrees. The transflective display device of claim 6, wherein the 50% maximum light intensity envelope surface of the second optical pattern has an angle of 20 degrees. The transflective display device of claim 6, wherein the lower surface is coated with an optical adhesive to be bonded to the liquid crystal layer, and the first optical type and the second optical type are connected to each other. The ratio is 2:8. The semi-transmissive display device of claim 6, wherein the microstructures are trapezoidally concavely distributed on the light-emitting surface, and the angle between the bottom of each of the microstructures and the sidewall is 130 to 150 degrees.