TWI430154B - Optical touch-sensing display panel - Google Patents

Description

Optical touch display panel

The present invention relates to a touch display panel, and more particularly to an optical touch display panel.

The touch panel can be roughly divided into a resistive touch panel, a capacitive touch panel, an optical touch panel, an acoustic wave touch panel, and an electromagnetic touch panel according to different sensing methods. Since the touch mechanism of the optical touch panel is suitable for use in a large-sized display panel, the touch function of the large-size display panel is mostly achieved through an optical touch mechanism. Most of the current optical touch display panels use infrared light as a light source, and a complementary CMOS optical sensor is used to sense the infrared light to estimate the position of the touch point. In the prior art, the intensity of the infrared light at the edge corresponding to the display panel is generally weaker, so when the user touches the edge of the display panel, the touch signal sensed by the complementary MOS photosensor is sensed. The intensity is weak, which makes the touch signal difficult to be detected, which leads to a decrease in touch sensitivity. Generally, the touch sensitivity is poor at a corner far from the complementary MOS photosensor, and even a malfunction is likely to occur.

The invention provides an optical touch display panel with a uniform sensing light source.

The invention provides an optical touch display panel comprising a liquid crystal display panel, at least one sensing component and a side edge light-indicating backlight. The sensing element is disposed at an edge of the liquid crystal display panel. The side-lit backlight is disposed below the liquid crystal display panel. The edge-lit backlight includes a light guide plate, a plurality of first light sources, a plurality of second light sources, and a plurality of auxiliary light sources. The light guide plate is located below the liquid crystal display panel, wherein the sensing element corresponds to one corner of the light guide plate. The first light source is adapted to provide a visible light to the light guide plate. The second light source is adapted to provide a non-visible light to the light guide. The auxiliary light source is adapted to provide an auxiliary non-visible light to the light guide plate, wherein the auxiliary light source is disposed at the remaining corners of the light guide plate. When the liquid crystal display panel is touched, the non-visible light and the auxiliary non-visible light passing through the liquid crystal display panel are scattered, and the sensing element is adapted to sense the scattered non-visible light and the auxiliary non-visible light to estimate the position of the touch point.

In an embodiment of the invention, the non-visible light is an infrared light, and the sensing elements comprise infrared light sensing elements.

In an embodiment of the invention, the infrared light sensing component comprises a complementary metal oxide semiconductor photosensor.

In one embodiment of the present invention, the number of the sensing elements is two, and are respectively disposed at two adjacent corners of the liquid crystal display panel.

In an embodiment of the invention, the first light source and a portion of the second light source are integrated into a first light strip, and the remaining first light source and the second light source are integrated into a second light strip. In addition, the first light bar and the second light bar are respectively disposed on two opposite sides of the light guide plate.

In an embodiment of the invention, the first light strip is disposed between the sensing elements.

In an embodiment of the invention, the auxiliary light source is integrated into a plurality of third light strips, and the third light strip is disposed at a corner of the light guide plate.

In an embodiment of the invention, the extending direction of the third light strip is substantially perpendicular to the extending direction of the second light strip.

In an embodiment of the invention, the arrangement direction of the auxiliary light sources is substantially perpendicular to the arrangement direction of the second light sources.

In an embodiment of the invention, the auxiliary light source is integrated on the second light strip and distributed on both ends of the second light strip.

In an embodiment of the invention, the arrangement direction of the auxiliary light sources is substantially parallel to the arrangement direction of the second light sources.

In an embodiment of the invention, the visible light is a white light.

In addition, the present invention also provides another optical touch display panel comprising a liquid crystal display panel, at least one sensing element, and a side-edge light-indicating backlight. The sensing element is disposed at an edge of the liquid crystal display panel. The side-lit backlight is disposed below the liquid crystal display panel. The edge-lit backlight includes a light guide plate, a plurality of first light sources, and a plurality of second light sources. The light guide plate is located below the liquid crystal display panel, wherein the sensing element corresponds to one corner of the light guide plate. The first light source is adapted to provide a visible light to the light guide plate. The second light source is adapted to provide a non-visible light to the light guide plate, wherein a portion of the second light source adjacent to the corner of the light guide plate provides a non-visible light intensity I ₁ that is higher than a non-visible light intensity I ₂ provided by the remaining second light source. When the liquid crystal display panel is touched, the non-visible light passing through the liquid crystal display panel is scattered, and the sensing element is adapted to sense the scattered non-visible light and the auxiliary non-visible light to estimate the position of the touch point.

In an embodiment of the invention, adjacent to a portion of the corner of the light guide plate The second light source has a luminous efficiency E1, and the remaining second light sources have a luminous efficiency E2, and E1>E2.

In an embodiment of the invention, a portion of the second source adjacent the corner of the light guide plate has a power P1 and the remaining second source has a power P2 and P1 > P2.

In an embodiment of the invention, a portion of the second light source adjacent to the corner of the light guide plate is integrated into a portion of the first light source.

Based on the above, the embodiment of the present invention enhances the uniformity of the sensing light source in the sensing region by enhancing the non-visible light intensity of the non-visible light source at the corner of the light guide plate, thereby improving the sensitivity of the optical touch display panel. .

The above described features and advantages of the present invention will be more apparent from the following description.

[First Embodiment]

1 is a schematic view of an optical touch display panel according to a first embodiment of the present invention, wherein FIG. 1 is a cross-sectional view of the optical touch display panel, and FIG. 1 is a top view of the optical touch display panel. . Referring to FIG. 1 , the optical touch display panel 100 of the present embodiment includes a liquid crystal display panel 110 , at least one sensing component 120 , and a side edge light-emitting backlight 130 . The sensing element 120 is disposed at an edge of the liquid crystal display panel 110 , and the side entrance light-emitting backlight 130 is disposed under the liquid crystal display panel 110 .

The edge-lit backlight 130 includes a light guide plate 132, a plurality of first light sources 134, and a plurality of second light sources 136. The light guide plate 132 is located in the liquid crystal display Below the display panel 110, the sensing element 120 corresponds to one of the corners A of the light guide plate 132. The first light source 134 is adapted to provide a visible light L1 to the light guide plate 132, and the visible light L1 is modulated by the liquid crystal display panel 110 to generate an image. The second light source 136 is adapted to provide a non-visible light L2 to the light guide plate 132. The auxiliary light source 138 is adapted to provide an auxiliary non-visible light L3 to the light guide plate 132, wherein the auxiliary light source 138 is disposed at the remaining corners B, C of the light guide plate 132.

In detail, a portion of the first light source 134 and a portion of the second light source 136 of the embodiment are integrated into a first light bar LB1, and the remaining first light source 134 and the second light source 136 are integrated into a first Two light bars LB2. The first light bar LB1 and the second light bar LB2 are respectively disposed on two opposite sides of the light guide plate 132 (ie, on two opposite sides of the liquid crystal display panel 110), and the first light bar LB1 is disposed, for example, on the sensing element 120. between. In addition, the arrangement direction of the auxiliary light sources 138 is substantially perpendicular to the arrangement direction of the second light sources 136.

In addition, as shown in FIG. 1 , the auxiliary light source 138 is integrated into a plurality of third light strips LB3 , wherein the number of the third light strips LB3 is, for example, two, and are respectively disposed at the corner B of the light guide plate 132 , C. In addition, the extending direction of the third light bar LB3 is substantially perpendicular to the extending direction of the second light bar LB2. It should be noted that in other feasible embodiments, the second light bar LB2 and the third light bar LB3 may be further integrated into a single light bar to reduce assembly man-hour and assembly cost.

In the present embodiment, when the touch point P1 near the corner of the liquid crystal display panel 110 is touched, part of the non-visible light L2 passing through the liquid crystal display panel 110 (ie, the non-visible light L2 near the touch point P1) and the auxiliary non- The visible light L3 is scattered, and the sensing element 120 is adapted to sense the scattered non-visible light L2 and the auxiliary invisible light L3 are used to derive the position of the touch point P1. In detail, when the user touches the liquid crystal display panel 110 with the finger F, the non-visible light L2 and the auxiliary non-visible light L3 near the touch point P1 are scattered. The scattered part of the non-visible light L2 and the auxiliary invisible light L3 are transmitted toward the sensing element 120, thereby enabling the sensing element 120 to estimate the position of the touch point P1. It should be noted that, in this embodiment, the auxiliary light source 138 is disposed at the remaining corners B, C of the light guide plate 132 to improve the sensibility of the sensing element 120 to the touch point farther away from it.

On the other hand, the liquid crystal display panel 110 of the present embodiment is, for example, a transmissive liquid crystal display panel or a transflective liquid crystal display panel. As shown in FIG. 1, the liquid crystal display panel 110 includes, for example, two substrates 112a and 112b, a liquid crystal layer 114 between the two substrates 112a and 112b, and a pixel array 116 disposed on the substrate 112a. When the visible light L1 passes through the liquid crystal layer 114 of the liquid crystal display panel 110 and the pixel array 116, an image is generated. In addition, since the transmissive liquid crystal display panel and the transflective liquid crystal display panel have a certain degree of light transmission area, the non-visible light L2 and the auxiliary non-visible light L3 penetrating from the light transmissive areas can be used as The sensing light source of the touch panel.

With reference to FIG. 1 , the number of the sensing elements 120 of the present embodiment is, for example, two, and are respectively disposed at two adjacent corners of the liquid crystal display panel 110 , and each sensing element 120 can be detected according to the non-detection. The incident angle of the visible light L2 and the auxiliary non-visible light L3 touches the position of the point P1. In detail, when the liquid crystal display panel 110 is touched, the non-visible light L2 and the auxiliary non-visible light L3 of the touch point P1 are scattered, so that the sensing element 120 detects the scattered non-visible light L2 and the auxiliary non-visible light L3. . Then, with The touch signal readout circuit 140 electrically connected to the sensing component 120 estimates the position of the touch point P1 according to the signal transmitted by the sensing component 120. In this embodiment, the visible light L1 is, for example, a white light, the non-visible light L2 is, for example, an infrared light, and the sensing element 120 for detecting the non-visible light L2 is, for example, an infrared light sensing element. For example, the infrared light sensing element described above may be a complementary metal oxide semiconductor light sensor.

In general, by the above method, the uniformity of the sensing light source (that is, the invisible light L2 and L3 of the embodiment) in the sensing region can be improved, thereby increasing the sensitivity of the optical touch display panel 100.

[Second embodiment]

2 is a schematic view of an optical touch display panel according to a second embodiment of the present invention, wherein FIG. 2 is a cross-sectional view of the optical touch display panel, and FIG. 2 is a top view of the optical touch display panel. . . The optical touch display panel 200 of the present embodiment is similar to the optical touch display panel 100 of FIG. 1 , but the main difference is that the auxiliary light source 138 of the embodiment is integrated on the second light strip LB2. And distributed at both ends of the second light bar LB2, such as the regions E1 and E2. In addition to this, the arrangement direction of the auxiliary light sources 138 is substantially parallel to the arrangement direction of the second light sources 136.

In this embodiment, the auxiliary light source 138 providing non-visible light is integrated on both ends of the second light strip LB2, so that the optical touch display panel 200 can have a uniform sensing light source, thereby increasing the sensing element 120 for the distance thereof. The touch sensitivity of the touch point P2 is farther away. Viewed from another angle, this embodiment utilizes increasing the number of non-visible light sources at both ends of the second light bar LB2, thereby improving the uniformity of the sensing light source in the sensing region, thereby increasing the optical type. The sensitivity of the touch display panel 200.

[Third embodiment]

3 is a schematic view of an optical touch display panel according to a third embodiment of the present invention, wherein FIG. 3 is a cross-sectional view of the optical touch display panel, and FIG. 3 is a top view of the optical touch display panel. . . The optical touch display panel 300 of the present embodiment is similar to the optical touch display panel 100 of FIG. 1 , but the main difference between the two is that the optical touch display panel 300 uses the second light source 236 a , and does not use FIG. 1 . Medium auxiliary light source 138. In detail, the optical touch display panel 300 includes a plurality of second light sources 236a, 236b. The second light sources 236a, 236b are adapted to provide the non-visible light L4, L5 to the light guide plate 132, wherein the light guide plate 132 is disposed under the liquid crystal display panel 110.

In this embodiment, the non-visible light intensity I ₁ provided by the partial second light source 236a adjacent to the light guide plate 132 or the corners B, C of the liquid crystal display panel 110 is higher than the non-visible light intensity I ₂ provided by the remaining second light source 236b. . When the touch point P3 of the liquid crystal display panel 110 is touched, the non-visible lights L4 and L5 passing through the liquid crystal display panel 110 are scattered, so that the sensing element 120 can sense the scattered non-visible light L4, L5 to calculate the touch. Touch the position of P3.

Further, in the present embodiment, a portion of the second light source 236a adjacent to the corners B, C of the light guide plate 132 has, for example, a luminous efficiency E1, and the remaining second light sources 236b have, for example, luminous efficiency E2, and E1 > E2. Therefore, by arranging the second light source 236a having high luminous efficiency at the corners B and C of the liquid crystal display panel 110, the sensibility of the sensing element 120 to the touch point farther away from it can be increased, thereby enhancing the optical touch. Control display panel 300 Touch sensitivity.

In addition, in other embodiments, the high power second light source can also be disposed at the corners B, C of the liquid crystal display panel 110 to achieve the same effect. For example, a portion of the second light source 236a adjacent to the corners B, C of the light guide plate 132 (or liquid crystal display panel 110) has, for example, power P1, while the remaining second light source 236b has power P2, and P1 > P2. The high power second light source 236a can be generated by selecting the large size second light source 236a or by driving the second light source 236a in an overdrive manner.

On the other hand, in another embodiment, a portion of the second light source 236a adjacent to the light guide plate 132 or the corners B, C of the liquid crystal display panel 110 may also be integrated into a portion of the first light source 134. In detail, the second light source 236a is further included in the package of the first light source 134 adjacent to the corner B or C, so that the non-visible light intensity of the second light source 236a can be made higher than the non-visible light intensity of the remaining second light source 236b. Viewed from another angle, the above practice is similar to the second embodiment in that the number of second light sources 136 is increased to produce a uniform sensing light source.

In summary, the embodiment of the present invention enhances the uniformity of the sensing light source in the sensing area by enhancing the non-visible light intensity of the non-visible light source at the corner of the light guiding plate, thereby improving the touch of the optical touch display panel. Control sensitivity.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the invention, and any one of ordinary skill in the art can make some modifications and refinements without departing from the spirit and scope of the invention. The scope of the invention is defined by the scope of the appended claims.

100, 200, 300‧‧‧ optical touch display panel

110‧‧‧LCD panel

112a, 112b‧‧‧ substrate

114‧‧‧Liquid layer

116‧‧‧ pixel array

120‧‧‧Sensor components

130‧‧‧Side-edge light backlight

132‧‧‧Light guide plate

134‧‧‧first light source

136, 236a, 236b‧‧‧ second light source

138‧‧‧Auxiliary light source

140‧‧‧Touch signal readout circuit

A~C‧‧‧ corner

E1, E2‧‧‧ area

L1‧‧‧ visible light

L2~L5‧‧‧Non-visible light

P1~P3‧‧‧ touch point

F‧‧‧ finger

LB1‧‧‧first light strip

LB2‧‧‧Second light strip

LB3‧‧‧third light strip

FIG. 1 is a schematic diagram of an optical touch display panel according to a first embodiment of the present invention.

2 is a schematic diagram of an optical touch display panel according to a second embodiment of the present invention.

FIG. 3 is a schematic diagram of an optical touch display panel according to a third embodiment of the present invention.

100‧‧‧Optical touch display panel

110‧‧‧LCD panel

112a, 112b‧‧‧ substrate

114‧‧‧Liquid layer

116‧‧‧ pixel array

120‧‧‧Sensor components

130‧‧‧Side-edge light backlight

132‧‧‧Light guide plate

134‧‧‧first light source

136‧‧‧second light source

138‧‧‧Auxiliary light source

140‧‧‧Touch signal readout circuit

A~C‧‧‧ corner

L1‧‧‧ visible light

L2~L3‧‧‧Non-visible light

P1‧‧‧ touch point

F‧‧‧ finger

LB1‧‧‧first light strip

LB2‧‧‧Second light strip

LB3‧‧‧third light strip

Claims (17)

An optical touch display panel includes: a liquid crystal display panel; at least one sensing component disposed at an edge of the liquid crystal display panel; and an optical backlight of one side, disposed under the liquid crystal display panel, the side The light-receiving backlight includes: a light guide plate under the liquid crystal display panel, wherein the sensing component corresponds to one corner of the light guide plate; and the plurality of first light sources are adapted to provide a visible light to the light guide plate; a second light source adapted to provide a non-visible light to the light guide plate; and a plurality of auxiliary light sources adapted to provide an auxiliary non-visible light to the light guide plate, wherein the auxiliary light source is disposed at a remaining corner of the light guide plate, when When the liquid crystal display panel is touched, the non-visible light passing through the liquid crystal display panel and the auxiliary non-visible light are scattered, and the sensing element is adapted to sense the scattered non-visible light and the auxiliary non-visible light to estimate the touch point. s position. The optical touch display panel of claim 1, wherein the liquid crystal display panel comprises a transmissive liquid crystal display panel or a transflective liquid crystal display panel. The optical touch display panel of claim 1, wherein the non-visible light is an infrared light, and the sensing elements comprise infrared light sensing elements. The optical touch display panel of claim 3, wherein the infrared light sensing elements comprise complementary metal oxide semiconductor light sensors. The optical touch display panel of claim 1, wherein the number of the at least one sensing element is two, and are respectively disposed at two adjacent corners of the liquid crystal display panel. The optical touch display panel of claim 5, wherein a part of the first light source and a part of the second light source are integrated into a first light strip, and the remaining first light source is integrated with the second light source system. It is a second light strip, and the first light strip and the second light strip are respectively disposed on two opposite sides of the light guide plate. The optical touch display panel of claim 6, wherein the first light strip is disposed between the sensing elements. The optical touch display panel of claim 7, wherein the auxiliary light sources are integrated into a plurality of third light strips, and the third light strips are disposed at corners of the light guide plate. The optical touch display panel of claim 8, wherein the third light strips extend substantially perpendicular to the extending direction of the second light strip. The optical touch display panel of claim 7, wherein the auxiliary light sources are arranged substantially perpendicular to the arrangement direction of the second light sources. The optical touch display panel of claim 7, wherein the auxiliary light sources are integrated on the second light strip and distributed at both ends of the second light strip. The optical touch display panel of claim 7, wherein the auxiliary light sources are arranged substantially parallel to the arrangement direction of the second light sources. The optical touch display surface as described in claim 1 a plate in which the visible light is a white light. An optical touch display panel includes: a liquid crystal display panel; at least one sensing component disposed at an edge of the liquid crystal display panel; and an optical backlight of one side, disposed under the liquid crystal display panel, the side The light-receiving backlight includes: a light guide plate under the liquid crystal display panel, wherein the sensing component corresponds to one corner of the light guide plate; and the plurality of first light sources are adapted to provide a visible light to the light guide plate; a plurality of second light sources adapted to provide a non-visible light to the light guide plate, wherein a portion of the second light source adjacent to a corner of the light guide plate provides a non-visible light intensity I ₁ higher than that provided by the remaining second light sources Non-visible light intensity I ₂ , when the liquid crystal display panel is touched, the non-visible light passing through the liquid crystal display panel is scattered, and the sensing element is adapted to sense the scattered non-visible light to estimate the position of the touch point . The optical touch display panel of claim 14, wherein a portion of the second light source adjacent to a corner of the light guide plate has a luminous efficiency E1, and the remaining second light sources have a luminous efficiency E2, and E1>E2 . The optical touch display panel of claim 14, wherein a portion of the second light source adjacent to a corner of the light guide plate has a power P1 and the remaining second light source has a power P2 and P1 > P2. The optical touch display panel of claim 14, wherein a portion of the second light source adjacent to a corner of the light guide plate is integrated into a portion of the first light source.