CN103164084B - Optical touch device and its display module and light source assembly - Google Patents

Abstract

An optical touch device comprises a sensing region, at least one light source component and a light sensing component. The at least one light source assembly is configured beside at least one side of the sensing region. The light source component comprises a plurality of first point light sources, and the first point light sources are suitable for sequentially providing first light beams to the sensing area. The sensing field of the light sensing component covers the sensing area, and the light sensing component is suitable for sensing the first light beam. In addition, the invention further provides a display module and a light source assembly for the optical touch device. The optical touch device and the display module and the light source component thereof have lower cost.

Description

Optical touch device and its display module and light source assembly

technical field

The present invention relates to a touch device, and in particular to an optical touch device and a display module and a light source assembly used in the optical touch device.

Background technique

Touch devices have the advantage of being easy to operate, so they have been widely used in various electronic products in recent years, such as mobile phones, tablet computers, digital cameras, music players, satellite navigation devices, touch screens, and the like. Currently common touch devices include resistive touch devices, capacitive touch devices, and optical touch devices. Among them, optical touch devices have become more and more popular due to their advantages of better durability and lower cost. be valued.

FIG. 1 is a schematic top view of a conventional optical touch device. Please refer to FIG. 1 , the existing optical touch device 100 includes a plurality of point light sources 110 arranged along the X axis, a plurality of point light sources 120 arranged along the Y axis, and a plurality of point light sources 120 arranged along the X axis and corresponding to the point light sources 110. The light sensing element 130 and a plurality of light sensing elements 140 arranged along the Y axis and corresponding to the point light sources 120 . The sensing area 102 is located between the point light sources 110 , 120 and the light sensing elements 130 , 140 . Each light sensing element 130 is used for receiving the light beam 112 provided by the corresponding point light source 110 , and each light sensing element 140 is used for receiving the light beam 122 provided by the corresponding point light source 120 .

When the user uses the finger 50 to manipulate in the sensing area 102, the finger 50 will block the light beams 112, 122 provided by some point light sources 110, 120 (such as point light sources 110a, 120a), causing some light sensing components 130, The light signal received by 140 (such as the light sensing components 130a, 140a) is weakened, so that the position of the finger 50 can be determined. However, the existing optical touch device 100 needs to use too many light sensing components 130 , 140 , resulting in high cost.

Contents of the invention

The invention provides an optical touch device to reduce costs.

The invention further provides a light source assembly for an optical touch device to reduce the cost of the optical touch device.

The present invention further provides a display module for an optical touch device to reduce the cost of the optical touch device.

In order to achieve the above advantages, the present invention provides an optical touch device, which includes a sensing area, at least one light source unit and a light sensing unit, wherein the light source unit is disposed on at least one side of the sensing area. The light source assembly includes a plurality of first point light sources, and the first point light sources are suitable for sequentially providing first light beams into the sensing area. The sensing field of view of the light sensing element covers the sensing area and is suitable for sensing the first light beam.

In an embodiment of the present invention, the above-mentioned sensing area is rectangular and has a first side, a second side, a third side and a fourth side, and the first side is opposite to the third side , the second side is opposite the fourth side. In addition, the light source component is disposed beside the first side, and the light sensing component is disposed at the junction of the third side and the fourth side.

In an embodiment of the present invention, the quantity of the above-mentioned at least one light source component is two, and the sensing area is rectangular, having a first side, a second side, a third side and a fourth side, and The first side is opposite to the third side, and the second side is opposite to the fourth side. In addition, the light source component is disposed beside the first side, and the light sensing component is disposed at the junction of the third side and the fourth side.

In an embodiment of the present invention, the above-mentioned optical touch device further includes a display panel and a light guide plate, wherein the display panel has a display surface and a back surface, and the sensing area is located on the display surface. The light guide plate has a light-emitting surface opposite to the back surface and a plurality of side surfaces connected to the light-emitting surface, and the light source component is opposite to one of the side surfaces.

In an embodiment of the present invention, the above-mentioned light source assembly further includes a plurality of second point light sources, and each second point light source is suitable for providing a second light beam. The first light beam is invisible light, including infrared light emitting diodes, and the second light beam is visible light, including white light emitting diodes.

In an embodiment of the present invention, the above-mentioned first point light sources and second point light sources are alternately arranged on a line.

In an embodiment of the present invention, the above-mentioned first point light sources are arranged on the first line, and the second point light sources are arranged on the second line.

In an embodiment of the present invention, the above-mentioned first line is parallel to the second line.

In an embodiment of the present invention, the above-mentioned optical touch device further includes at least one white light source, and the white light source and the light source assembly are respectively opposite to different sides of the light guide plate.

In an embodiment of the present invention, the above-mentioned first point light sources are arranged at intervals.

In an embodiment of the present invention, the above-mentioned optical touch device further includes a substrate, and the sensing area is on the substrate.

In an embodiment of the present invention, the above-mentioned optical touch device further includes a light source control unit electrically connected to the first point light source, so as to control the first point light source to sequentially provide the first light beam.

In an embodiment of the present invention, the above-mentioned first light beam is invisible light.

In an embodiment of the present invention, the above-mentioned light source assembly further includes a carrier board, and the first point light source is disposed on the carrier board.

In order to achieve the above advantages, the present invention further provides a light source assembly for an optical touch device, including a plurality of first point light sources and a light source control unit. The first point light source is arranged on the substrate of the optical touch device, and the light source control unit is electrically connected to the first point light source for controlling the switch of the first point light source according to a predetermined sequence.

In an embodiment of the present invention, the above-mentioned light source assembly for an optical touch device further includes a plurality of second point light sources disposed on the substrate and electrically connected to the light source control unit, the first point light sources are invisible light light source, and the second point light source is a visible light source, and the light source control unit further controls the switch of the second point light source.

In an embodiment of the present invention, the above-mentioned first point light source is an invisible light source.

In an embodiment of the present invention, the above-mentioned light source assembly for an optical touch device further includes a carrier plate disposed on the substrate, and the first point light source is fixed on the carrier plate.

In order to achieve the above advantages, the present invention further proposes a display module for an optical touch device, including a substrate, a light guide plate, and a light source assembly. The light guide plate is arranged above the substrate, and the light source component is arranged beside at least one side of the light guide plate. Wherein a sensing area is formed above the light guide plate. In addition, the light source assembly includes a plurality of first point light sources and a light source control unit, wherein the light source control unit is electrically connected to the first point light sources for controlling the first point light sources on and off according to a predetermined sequence.

In an embodiment of the present invention, the above-mentioned light source assembly further includes a plurality of second point light sources electrically connected to the light source control unit. In addition, the first point light source is an invisible light source, and the second point light source is a visible light source, and the light source control unit further controls the switch of the second point light source.

In an embodiment of the present invention, the above-mentioned first point light source is an invisible light source.

In an embodiment of the present invention, the above-mentioned light source assembly further includes a carrier plate disposed on the substrate, and the first point light source is fixed on the carrier plate.

In the light source component, display module and optical touch device of the present invention, since the point light sources can emit light sequentially, only a single light sensing component can achieve the purpose of recognizing the position of the object in the sensing area. In this way, the number of light sensing components can be reduced, thereby reducing the cost of the optical touch device.

The above description is only an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention, it can be implemented according to the contents of the description, and in order to make the above and other purposes, features and advantages of the present invention more obvious and understandable , the following preferred embodiments are specifically cited below, and are described in detail as follows in conjunction with the accompanying drawings.

Description of drawings

FIG. 1 is a schematic top view of a conventional optical touch device.

FIG. 2 is a schematic top view of an optical touch device according to an embodiment of the present invention.

FIG. 3A is a schematic diagram of the optical touch device in FIG. 2 when sensing the position of an object.

FIG. 3B is a schematic diagram of the optical touch device in FIG. 2 when sensing the position of an object.

FIG. 4 is a schematic top view of an optical touch device according to another embodiment of the present invention.

FIG. 5 is a schematic top view of an optical touch device according to another embodiment of the present invention.

FIG. 6A is a schematic cross-sectional view along line I-I of FIG. 5 .

FIG. 6B is a schematic cross-sectional view of an optical touch device according to another embodiment of the present invention.

FIG. 7 is a schematic cross-sectional view along line II-II of FIG. 5 .

FIG. 8 is a schematic diagram of a light source assembly for an optical touch device according to another embodiment of the present invention.

FIG. 9 is a schematic diagram of a light source assembly for an optical touch device according to another embodiment of the present invention.

detailed description

In order to further explain the technical means and effects of the present invention to achieve the intended purpose of the invention, the specific implementation of the optical touch device and its display module and light source assembly according to the present invention will be described below in conjunction with the accompanying drawings and preferred embodiments. , structure, feature and effect, detailed description is as follows.

FIG. 2 is a schematic top view of an optical touch device according to an embodiment of the present invention. Please refer to FIG. 2 , the optical touch device 200 of this embodiment includes a sensing area 230 , a light source assembly 220 and a light sensing assembly 210 , wherein the light source assembly 220 is disposed on the side of the sensing area 230 , and the light sensing assembly 210 is located such that its sensing field of view covers the entire sensing region 230 . The light source assembly 220 includes a plurality of point light sources 221, and these point light sources 221 are adapted to provide a first light beam (not shown) in the sensing area 230 in time sequence, and the light sensing element 210 is adapted to sense the first light beam. The first light beam in this embodiment is, for example, invisible light. The invisible light is, for example, infrared light, that is, the point light source 221 is, for example, an infrared light emitting diode.

The light sensing element 210 is, for example, disposed above the sensing region 230 to detect the optical signal (ie, the first light beam) provided by the light source element 220 . The light source unit 220 can be located above the side-sensing area 230 to provide an optical signal that can directly enter the sensing area 230 . In another embodiment, the sensing area 230 can be located above the light guide plate (not shown), and the light source unit 220 is located beside the light guide plate, and the optical signal provided by the light source unit 220 is guided into the sensing area 230 through the light guide plate.

In this embodiment, the sensing area 230 is rectangular, for example, and has a first side 231, a second side 232, a third side 233 and a fourth side 234, wherein the first side 231 and the third side The side 233 is opposite, the second side 232 is opposite to the fourth side 234 , and the light source assembly 220 is disposed beside the first side 231 of the sensing region 230 , for example. In addition, in order to be suitable for sensing the aforementioned first light beam, the light sensing component 210 may be disposed at a corner opposite to the first side 231 , for example, at the junction of the third side 233 and the fourth side 234 .

In addition, the light source assembly 220 may further include a carrier board 223 in addition to the point light source 221 , and the point light source 221 is disposed on the carrier board 223 , but the present invention does not limit the point light source 221 to be disposed on the carrier board 223 . In this embodiment, the point light sources 221 are arranged at intervals. Since the user usually controls with fingers, the spacing D between the point light sources 221 is, for example, slightly smaller than the width of a normal finger. The finger width of a general user is about 12 mm, and the distance D can be designed to be less than 12 mm, such as 10 mm, to improve the sensing accuracy.

The optical touch device 200 may further include a light source control unit 260 , which is electrically connected to the point light source 221 to control the point light source 221 to switch on and off according to a predetermined sequence, so that the point light source 221 sequentially provides the first light beam to the sensing area 230 . In this embodiment, the light source control unit 260 is electrically connected to the point light source 221 through the carrier board 223 . However, in the embodiment where the point light sources 221 are not carried by the carrier board 223 , the light source control unit 260 can be electrically connected to the point light sources 221 respectively through a plurality of signal lines. In addition, each point light source 221 emits light for approximately 0.1 millisecond (ms) to 1 millisecond, but not limited thereto. In addition, the optical touch device 200 may further include a substrate 240 , and the sensing region 230 is located on the surface of the substrate 240 , and the light sensing unit 210 , the light source unit 220 and the light source control unit 260 are disposed on the substrate 240 .

In this embodiment, since the point light sources 221 can emit light in sequence, when one of the point light sources 221 emits light, the rest of the point light sources 221 do not emit light, so only one light sensing component 210 can be used to determine the sensing area 230 on the location of the object. The sensing method of the object position of the optical touch device 200 of this embodiment will be described below with reference to the drawings.

3A and 3B are schematic diagrams of the optical touch device in FIG. 2 when sensing the position of an object. Please refer to FIG. 3A first. The light source control unit 260, for example, controls the point light sources 221a to 221j to emit light in sequence to scan whether there is an object 60 in the sensing area 230, and thereby sense the object 60 (such as a finger) in the sensing area 230. s position. When the point light source 221a emits light, the first light beam 222 will not be blocked by the object 60, so the light sensing component 210 can sense the entire bright line. Next, the light source control unit 260 continues to control the point light sources 221b to 221j to emit light sequentially.

3B, when the point light source 221d emits light, the object 60 will block the first light beam 222, and the light sensing component 210 can sense the position where the bright line is blocked, so it can be confirmed that the object 60 is on the straight line L1. In addition, since the optical path L2 of the first light beam 222 provided by the point light source 221d is known information, the intersection position of the straight line L1 and the optical path L2 can be calculated, and the intersection position is the position information of the object 60 . Therefore, the optical touch device 200 of this embodiment can sense the position of the object 60 through only one light sensing component 210 , thereby reducing the cost.

It should be noted that, since the light provided by the point light sources 221c and 221e adjacent to the point light source 221d may also be partially blocked by the object 60, when the point light sources 221c and 221e emit light, the light sensing component 210 may also detect The position information of the object 60 is detected, so the obtained position information can be further processed by methods such as the center of gravity method or the center method during calculation, for example, the center of gravity of the weighted average can be calculated with reference to the captured brightness information as weight data position to calculate the precise position of the object 60. The center of gravity method and the center method are common knowledge in the art, and will not be described in detail here. In addition, in this embodiment, the optical touch device 200 may further include a processing unit 270, and the light sensing element 210 and the light source control unit 260 are, for example, electrically connected to the processing unit 270, and the processing unit 270 is used to The position of the object 60 is calculated by using the position information acquired by the component 210 and the light emission information of the point light source 221d. In other embodiments, the processing unit 270 can also be integrated into the light source control unit 260 or the light sensing component 210 , and the light source control unit 260 is electrically connected to the light sensing component 210 .

In addition, although the above-mentioned embodiment uses only one point light source 221 to emit light at the same time as an example to illustrate how the optical touch device 200 uses a single light sensing component 210 to achieve the purpose of sensing the position of the side object 60, the present invention is not limited Only one point light source 221 can be made to emit light at the same time period. In order to shorten the scanning time, two or more point light sources 221 can be made to emit light at the same time period. In another embodiment, the light emitting periods of different point light sources 221 may partially overlap to shorten the scanning time. For example, taking each point light source 221 to emit light for 1 millisecond as an example, when the point light source 221 a emits light for 0.5 milliseconds, the point light source 221 b is driven to emit light. When the point light source 221b emits light for 0.5 milliseconds, the point light source 221c is driven to emit light, and the point light source 221a is stopped to emit light.

The light-emitting time and sequential light-emitting manner of the above-mentioned point light sources 221 can be adjusted according to the requirements or limitations of the overall structure of the optical touch device 200 , and are not limited to the above-mentioned embodiments. FIG. 4 is a schematic top view of an optical touch device according to another embodiment of the present invention. Please refer to FIG. 4 , the optical touch device 300 of this embodiment is similar to the above-mentioned optical touch device 200 , the difference is that the optical touch device 300 includes two light source assemblies 220 , which are respectively arranged at the first of the sensing area 230 . Next to the side 231 and the second side 232, the light source control unit 260 is electrically connected to each point light source 221 of the two light source components 220 to control these point light sources 221 to emit light in sequence, so that the light sensing component 210 can obtain More position information helps to improve the sensing accuracy of the optical touch device 300 .

FIG. 5 is a schematic top view of an optical touch device according to another embodiment of the present invention, and FIG. 6A is a schematic cross-sectional view along line I-I of FIG. 5 . Please refer to FIG. 5 and FIG. 6A, the optical touch device 400 of this embodiment is a touch screen, which includes a display module 401, and the display module 401 includes a substrate 240, a light guide plate 420 and a light source assembly 220, wherein the light guide plate 420 is, for example, The light guide plate is configured on the substrate 240 , and the sensing area 230 is formed on the light guide plate 420 , for example. In addition, the display module 401 may further include a display panel 410 disposed on the light guide plate 420 , and the back surface 412 of the display panel 410 is opposite to the light emitting surface 424 of the light guide plate 420 . The display panel 410 is a transmissive display panel, such as a liquid crystal display panel. The light source assembly 220 is opposite to the side 422 of one of the light guide plate 420 connected to the light exit surface 424, and the first light beam 222 provided by the point light source 221 enters the light guide plate 420 from the side 422 and exits through the light exit surface 424 of the light guide plate 420, and passes through through the display panel 410. The light sensing component 210 can sense the first light beam 222 passing through the display panel 410 . In addition, an optical film (not shown), such as a prism sheet or a diffusion sheet, may be provided between the light guide plate 420 and the display panel 410, and a reflective sheet (not shown) may be provided between the light guide plate 420 and the substrate 240. . In this embodiment, the sensing area 230 is, for example, located on the display surface 414 of the display panel 410. When an object (not shown) is manipulated on the sensing area 230, the light sensing component 210 can sense the position information of the object. . The method for obtaining the position of the object is similar to the above embodiment, and will not be repeated here.

In another embodiment shown in FIG. 6B , the light source assembly 220 can be disposed above the sensing region 230 to directly provide the first light beam 222 to the sensing region 230 without passing the first light beam 222 through the light guide plate 420. Guided to the sensing region 230 . In FIG. 6B , for example, a support 250 is provided on the substrate 240 , and the light source assembly 220 is fixed on the support 250 , and the support 250 is used to elevate the light source assembly 220 above the sensing area 230 .

FIG. 7 is a schematic cross-sectional view along line II-II of FIG. 5 . Referring to FIG. 5 and FIG. 7 , the optical touch device 400 of this embodiment may further include a white light source 480 , which is opposite to another side 426 of the light guide plate 420 connected to the light-emitting surface 424 . The white light source 480 is used to provide white light 482 , and the white light 482 enters the light guide plate 420 through the side surface 426 of the light guide plate 420 and exits through the light output surface 424 to be used as display light of the display panel 410 .

In this embodiment, the white light source 480 is, for example, a lamp tube, but in other embodiments, a plurality of white light point light sources (such as white light emitting diodes) can also be used as the white light source. In addition, although this embodiment takes one white light source 480 and one light source assembly 220 as an example, in other implementations, the number of white light source 480 or light source assembly 220 may be multiple. For example, the number of the white light source 480 and the light source assembly 220 can be two respectively, and the white light source 480 and the light source assembly 220 are opposite to different sides of the light guide plate 420 .

It is worth mentioning that, in another embodiment, the above-mentioned display panel 410 of the optical touch device 400 can also be omitted, so as to serve as an optical touch device without a display function. In addition, in another embodiment, the above-mentioned white light source 480 and the light source assembly 220 can also be integrated into the same light source assembly. For example, as shown in FIG. 8 , the light source unit 520 includes a point light source 521 and a second point light source 522 . Wherein, the point light sources 521 and the point light sources 522 are arranged on the carrier board 523 and arranged alternately in a line, for example. The point light source 521 is adapted to provide a first light beam for sensing by the light sensing component. Therefore, the first light beam is, for example, invisible light. For example, the point light source 521 is, for example, an infrared light emitting diode to provide infrared light. The point light source 522 is suitable for providing the second light beam as display light of the display panel. Therefore, the second light beam is, for example, visible light. For example, the point light source 522 is, for example, a white light emitting diode to provide white light. If the light source assembly 520 is used to replace the light source assembly 220 in FIG. 5 , the white light source 480 in FIG. 5 can be omitted.

In another embodiment shown in FIG. 9 , the point light sources 521 and the point light sources 522 can be arranged in two rows. Specifically, the point light sources 521 of the light source assembly 620 are, for example, arranged on the first line L3, and the point light sources 522 are, for example, arranged on the second line L4. In addition, the first line L3 may be parallel to the second line L4.

To sum up, in the light source assembly, display module, and optical touch device of the present invention, since the point light sources can emit light sequentially, only a single light sensing element can achieve the purpose of recognizing the position of the object in the sensing area . In this way, the number of light sensing components can be reduced, thereby reducing the cost of the optical touch device.

The above description is only a preferred embodiment of the present invention, and does not limit the present invention in any form. Although the present invention has been disclosed as above with preferred embodiments, it is not intended to limit the present invention. Anyone familiar with this field Those skilled in the art, without departing from the scope of the technical solution of the present invention, may use the technical content disclosed above to make some changes or modify them into equivalent embodiments with equivalent changes, but as long as they do not depart from the technical solution of the present invention, the Technical Essence Any simple modifications, equivalent changes and modifications made to the above embodiments still fall within the scope of the technical solution of the present invention.

Claims (14)

1. An optical touch device, characterized in that, comprising: a sensing area; At least one light source unit is disposed on at least one side of the sensing area, the light source unit includes a plurality of first point light sources, and each of the first point light sources is adapted to provide a first light beam; a photo-sensing component whose sensing field of view covers the sensing area, and the photo-sensing component is suitable for sensing the first light beams; A display panel has a display surface and a back surface, the sensing area is located on the display surface; and A light guide plate has a light-emitting surface opposite to the back surface and a plurality of side surfaces connected to the light-emitting surface, the light source assembly is opposite to one of the side surfaces, and each of the first point light sources is suitable for sequentially laterally The first light beams are provided to directly enter the light guide plate, and the first light beams are adapted to shoot upwards toward the display surface sequentially, wherein the first light beams are parallel to each other, when one of the point light sources emits the first light beams When the light beam reaches the object, the object blocks the first light beam, so that the light sensing component senses the position where the first light beam is blocked, so as to confirm that the object is formed by connecting the light sensing component. and at the same time, obtain the position information of the object according to the time when the light sensing component senses the position where the first light beam is interrupted. 2. The optical touch device according to claim 1, wherein the sensing area is rectangular and has a first side, a second side, a third side and a fourth side , the first side is opposite to the third side, the second side is opposite to the fourth side, the light source component is disposed next to the first side, and the light sensing component is disposed on the third side edge and the fourth side. 3. The optical touch device according to claim 1, wherein the number of the at least one light source component is two, the sensing area is rectangular, and has a first side, a second side, A third side and a fourth side, the first side is opposite to the third side, the second side is opposite to the fourth side, and the light source components are respectively arranged on the first side Next to the second side, the light sensing component is disposed at the junction of the third side and the fourth side. 4. The optical touch device according to claim 1, wherein the light source assembly further comprises a plurality of second point light sources, and each second point light source is adapted to provide a second light beam, and the first light beam is Invisible light, the second light beam is visible light. 5. The optical touch device according to claim 4, wherein the first point light sources comprise infrared light emitting diodes, and the second point light sources comprise white light emitting diodes. 6 . The optical touch device according to claim 4 , wherein the first point light sources and the second point light sources are alternately arranged in a line. 7. The optical touch device according to claim 4, wherein the first point light sources are arranged on a first line, and the second point light sources are arranged on a second line. 8. The optical touch device according to claim 7, wherein the first line is parallel to the second line. 9 . The optical touch device according to claim 1 , further comprising at least one white light source, the white light source and the light source assembly are respectively opposite to the different sides of the light guide plate. 10. The optical touch device according to claim 1, wherein the first point light sources are arranged at intervals. 11. The optical touch device according to claim 1, further comprising a substrate on which the sensing area is located. 12. The optical touch device according to claim 1, further comprising a light source control unit electrically connected to the first point light sources to control the first point light sources to sequentially provide the first beam. 13. The optical touch device according to claim 1, wherein the first light beam is invisible light. 14. The optical touch device according to claim 1, wherein the light source unit further comprises a carrier, and the first point light sources are disposed on the carrier.