TWI490756B - Optical touch system - Google Patents

Description

Optical touch system

The present invention relates to the field of optical touch technology, and in particular to an optical touch system.

FIG. 1 is a schematic diagram of a conventional optical touch system. Referring to FIG. 1 , the optical touch system 10 includes a touch surface 100 , an image sensing device 110 , an image sensing device 120 , and a processing circuit 130 . The touch surface 100 has a quadrangular shape and four sides connected in sequence (indicated by 101 to 104, respectively). The image sensing device 110 is disposed at a corner where the first side 101 and the fourth side 104 of the touch surface 100 intersect, and the image sensing device 120 is disposed on the first side 101 and the second side of the touch surface 100. 102 intersecting corners. Image sensing device 110 can sense object 106 along sensing route 112, while image sensing device 120 can sense object 106 along sensing route 122. The processing circuit 130 is electrically coupled to the image sensing devices 110 and 120 to calculate the actual coordinate position of the object 106 according to the image of the object sensed by the two image sensing devices. That is, the processing circuit 130 can obtain the actual coordinate position of the object 106 as long as the intersection of the sensing paths 112 and 122 can be calculated. However, such an optical touch system 10 has a problem when performing multi-touch, which is illustrated in FIG. 2.

FIG. 2 is an explanatory diagram of multi-touch operation of the optical touch system 10, taking a two-touch as an example. In FIG. 2, the same reference numerals as those in FIG. 1 are indicated as being the same. Reference numerals, and reference numerals 206 and 208 are denoted as objects. As shown in FIG. 2, the image sensing device 110 can sense the objects 206 and 208 along the sensing paths 212 and 214, respectively, and the image sensing device 120 can sense along the sensing paths 222 and 224, respectively. To objects 206 and 208. However, since the processing circuit 130 obtains the coordinate positions of the objects 206 and 208 by calculating the intersection of the above sensing routes, in this case, the processing circuit 130 may consider that the points indicated by the numerals 216 and 218 may also be objects. The coordinates of 206 and 208 are located, that is, the so-called ghost point is generated. Therefore, the processing circuit 130 in such an optical touch system 10 will not be able to correctly calculate the actual coordinate positions of the objects 206 and 208.

The present invention provides an optical touch system that can accurately calculate the actual coordinate position of an object without being affected by ghost points.

The invention provides an optical touch system, which comprises a touch surface, a first object sensing module, a second object sensing module and a processing circuit. The first object sensing module includes a first image sensing device and a second image sensing device. The extension line center of the sensing range of the first image sensing device forms a first angle with the extension line of the center of the sensing range of the second image sensing device. The second object sensing module includes a first object sensing device and a second object sensing device. The first object sensing device and the second object sensing device are both disposed at the edge of the touch surface, and the extension line center of the sensing range of the first object sensing device and the sensing range of the second object sensing device are at the center The extension line forms a second angle. The processing circuit is electrically coupled to the first object sensing module and the second object sensing module. When the first object and the second object are adjacent to the touch surface, the processing circuit calculates the possible coordinate positions of the objects according to the image of the object sensed by the first object sensing module, so as to be the first candidate coordinate group. In addition, the processing circuit calculates the possible coordinate positions of the objects according to the object information sensed by the second object sensing module, so as to be the second candidate coordinate group. And further obtaining an intersection of the first candidate coordinate group and the second candidate coordinate group to treat the intersection as the actual coordinate position of the objects.

The invention further provides an optical touch system adapted to sense a plurality of objects. The optical touch system includes a touch surface, a first object sensing module, a second object sensing module and a processing circuit. The first object sensing module is configured to detect a first set of image information including the object, and calculate a first candidate coordinate group of the object. The second object sensing module is configured to detect a second set of image information including the object. The processing circuit is electrically coupled to the first object sensing module and the second object sensing module, and is configured to select at least part of coordinates from the first candidate coordinate group as the actual coordinates of the object according to the second group of image information. position.

The invention solves the foregoing problems, mainly establishes a plurality of coordinate systems in an optical touch system, and uses different coordinate systems to generate different ghost points, so that the candidate coordinate groups generated by each coordinate system can mutually confirm each candidate coordinate as a ghost. The point is also the actual coordinate, for example, the intersection of the candidate coordinate groups generated by each coordinate system is directly used as the actual coordinate position.

The above and other objects, features and advantages of the present invention will become more <RTIgt;

10, 30, 40, 50‧‧‧ optical touch system

130, 330, 430, 530‧‧‧ processing circuits

100, 300‧‧‧ touch surface

101, 301‧‧‧ first side

102, 302‧‧‧ second side

103, 303‧‧‧ third side

104, 304‧‧‧ fourth side

110, 120, 311, 312, 421, 422, 511, 512‧‧‧ image sensing devices

112, 122, 212, 222, 214, 224, 311-1, 311-2, 312-1, 312-2, 321-1, 321-2, 322-1, 322-2, 421-1, 421- 2, 422-1, 422-2, 511-1, 511-2‧‧‧ sensing route

106, 206, 208, 331, 332‧‧‧ objects

216, 218, 333, 334, 335, 336 ‧ ‧ ghost points

310, 320, 420‧‧‧ Object sensing module

321, 322‧‧‧photosensitive device

323‧‧‧Photosensitive elements

340, 350, 440, 450, 540, 550‧‧‧ illuminating devices

390‧‧‧Lighting module

391‧‧‧Single point lighting device

FIG. 1 is a schematic diagram of a conventional optical touch system.

2 is an explanatory diagram of multi-touching of the optical touch system shown in FIG. 1.

3A is a schematic diagram of an optical touch system in accordance with an embodiment of the invention.

Figure 3B shows one of the configurations of a single row of single point illumination devices.

Fig. 3C is an embodiment for explaining the arrangement position of the single-point light-emitting device and the arrangement position of the photosensitive elements.

4 is a schematic diagram of an optical touch system in accordance with another embodiment of the present invention.

FIG. 5 is a schematic diagram of an optical touch system according to still another embodiment of the present invention.

The present invention utilizes at least two object sensing modules to construct two coordinate systems of an optical touch system. One of the object sensing modules has two image sensing devices, and an extension line at the center of the sensing range of one of the image sensing devices forms an angle with an extension line of the center of the sensing range of the other image sensing device. . In addition, another object sensing module has two object sensing devices, and an extension line at the center of the sensing range of one of the object sensing devices forms an extension line with a center of the sensing range of the other object sensing device. Another angle. Therefore, when at least two objects are adjacent to the touch surface, the processing circuit can calculate the possible coordinate positions of the objects according to the image of the object sensed by one of the object sensing modules, so as to be the first candidate coordinate group. And calculating the possible coordinate positions of the objects according to the object information sensed by the other object sensing module, so as to be the second candidate coordinate group, so that the processing circuit further obtains the first candidate coordinate group and the second candidate coordinate group The intersection of the above-mentioned intersections is regarded as the actual coordinate position of these objects, thereby solving the problem of ghost points.

First embodiment:

3A is a schematic diagram of an optical touch system in accordance with an embodiment of the invention. As shown in FIG. 3A , the optical touch system 30 includes a touch surface 300 , an object sensing module 310 , an object sensing module 320 , and a processing circuit 330 . The touch surface 300 has a quadrangular shape and four sides connected in sequence (indicated by 301 to 304, respectively). The object sensing module 310 includes image sensing devices 311 and 312. The image sensing device 311 is disposed at a corner where the first side 301 and the fourth side 304 intersect, and the image sensing device 312 is disposed at a corner where the first side 301 and the second side 302 intersect. Each image sensing device has its sensing range, and the sensing range is related to the image width captured by the image sensing device. In this case The extension line at the center of the sensing range of the image sensing device 311 forms a first angle (in this case, a 135 degree angle) with an extension line of the center of the sensing range of the image sensing device 312.

The object sensing module 320 includes two object sensing devices, and the two object sensing devices are respectively implemented by the photosensitive devices 321 and 322. Each photosensitive device has a plurality of photosensitive elements (as indicated by the numeral 323). Each of the photosensitive elements 323 is configured to sense the light of the touch surface 300 and output a sensing signal (not shown). In this example, the photosensitive devices 321 and 322 are respectively disposed on the first side 301 and the fourth side 304 of the touch surface 300. However, such an arrangement is not intended to limit the present invention, and those skilled in the art will appreciate that the photosensitive devices 321 and 322 can be disposed on any two adjacent sides of the first side 301 to the fourth side 304, respectively. Each photosensitive device also has its sensing range, and the sensing range is the sum of the photosensitive ranges of all the photosensitive elements inside each photosensitive device. In this example, the extension line at the center of the sensing range of the photosensitive device 321 forms a second angle (in this case, a 90 degree angle) with the extension line of the center of the sensing range of the photosensitive device 322.

The processing circuit 330 is electrically coupled to the image sensing devices 311 and 312 to control the operation of each image sensing device and to receive an image of the object sensed by each image sensing device. In addition, the processing circuit 330 is also electrically coupled to each of the photosensitive elements 321 and 322 to control the operation of each photosensitive element and to receive the sensing signals generated by each of the photosensitive elements 323 to The sensing signals generated by all of the photosensitive elements 323 in a photosensitive device are regarded as a set of object information.

In the actual operation, when the objects 331 and 332 are adjacent to the touch surface 300, the processing circuit 330 calculates the possible coordinate positions of the objects 331 and 332 according to the object image sensed by the object sensing module 310, so as to be the first A candidate coordinate group. In detail, the image sensing device 311 in the object sensing module 310 can sense the objects 331 and 332 along the sensing paths 311-1 and 311-2, respectively, and the images in the object sensing module 310. The sensing device 312 can sense the objects 331 and 332 along the sensing routes 312-1 and 312-2, respectively, so the processing circuit 330 can calculate the sensing routes 311-1, 311-2, The intersection of 312-1 and 312-2 is to obtain the possible coordinate positions of the objects 331 and 332. Therefore, the processing circuit 330 will consider that the locations indicated by the numerals 333 and 334 may also be the coordinate positions at which the objects 331 and 332 are located. Therefore, the processing circuit 330 regards all intersections of the sensing routes 311-1, 311-2, 312-1, and 312-2 (including those indicated by the notations 331, 332, 333, and 334) as the first candidate coordinate group. .

Then, the processing circuit 330 calculates the possible coordinate positions of the objects 331 and 332 according to the object information sensed by the object sensing module 320, so as to be the second candidate coordinate group. In detail, the photosensitive device 321 in the object sensing module 320 can sense the objects 331 and 332 along the sensing paths 321-1 and 321-2, respectively, and the photosensitive device 322 in the object sensing module 320. Objects 331 and 332 can then be sensed along sensing paths 322-1 and 322-2, respectively. Therefore, the processing circuit 330 treats all the sensing signals output by each photosensitive device as a group of object information, and further obtains the sensing routes 321-1, 321-2, 322 based on the obtained two sets of object information. 1 and 322-2, and then the intersection of the sensing routes 321-1, 321-2, 322-1 and 322-2 is calculated to obtain possible coordinate positions of the objects 331 and 332. Therefore, the processing circuit 330 will consider that the locations indicated by the numerals 335 and 336 may also be the coordinate positions at which the objects 331 and 332 are located. Accordingly, processing circuit 330 will treat the intersection of sensed routes 321-1, 321-2, 322-1, and 322-2 (including where indicated by indices 331, 332, 335, and 336) as the second candidate coordinate group.

Since the actual coordinate positions of the objects 331 and 332 are all present in the candidate coordinate group of each coordinate system, in the first candidate coordinate group and the second candidate coordinate group, only the intersection of some sensing routes is the object 331 The actual coordinate position of 332 and the others are ghost points, so the processing circuit 330 further obtains the intersection of the first candidate coordinate group and the second candidate coordinate group to treat the intersection as the actual coordinate position of the objects 331 and 332. In this way, the optical touch system 30 is not affected by ghost points and misjudges the coordinate positions of the objects 331 and 332. The manner in which the processing circuit 330 obtains the intersection of the first candidate coordinate group and the second candidate coordinate group includes determining the second candidate coordinate Whether any coordinate position in the group is less than a preset distance from one of the first candidate coordinate groups, and each pair of coordinate positions whose distance is less than the preset distance is regarded as the first candidate coordinate group. Intersection with the second candidate coordinate group. Certainly, the processing circuit 330 obtains the intersection of the first candidate coordinate group and the second candidate coordinate group, or may determine whether any coordinate position in the first candidate coordinate group is in the second candidate coordinate group. The distance between one of the target positions is smaller than the preset distance, and each pair of coordinate positions whose distance is less than the preset distance is regarded as the intersection of the first candidate coordinate group and the second candidate coordinate group.

In addition, in the preferred hardware implementation of the present invention, the optical touch system 30 may further include at least three illumination devices, each of which is disposed on one of the first side 301 to the fourth side 304. And used to illuminate the image sensing devices 311 and 312. In this example, the optical touch system 30 uses three illumination devices in total, and two of the illumination devices (labeled 340 and 350 respectively) are respectively disposed on the second side 302 and the third side 303, and the remaining A light-emitting device (not shown) is disposed in superposition with the photosensitive device 322. In other words, when either side of the touch surface 300 is configured with both the light-emitting device and the light-sensing device, the light-emitting device needs to be superimposed with the photosensitive device. In addition, each of the light-emitting devices 30 can be directly replaced by a light-reflecting device, as long as each of the light-reflecting devices can reflect light to the image sensing devices 311 and 312. Of course, in the case where each of the light-emitting devices 30 is replaced by a light-reflecting device, each of the image sensing devices must have an infrared (IR) illumination device, for example, Infrared light emitting diode (IR LED). In addition, each of the image sensing devices described above must also have an infrared ray filtering device, such as an infrared filter (IR-pass filter), so that each image sensing device can pass through. The infrared filter device obtains an image on the touch surface 300.

It should be noted that the image sensing device 311 and the image sensing device 312 may use the same lighting device or different lighting devices. For example, if it’s a shadow The image sensing device 311 and the image sensing device 312 do not have an infrared illumination device, but all have an infrared filter device, and the designer of the optical touch system 30 can be in the touch surface 300 of the optical touch system 30. An infrared illuminating device is added to one side 301 to allow the image sensing device 311 and the image sensing device 312 to be used with the infrared illuminating device. Of course, the additional infrared illumination device must be superimposed with the photosensitive device 321 .

In addition, in order to increase the sensing efficiency of the photosensitive devices 321 and 322, the designer of the optical touch system 30 can add a plurality of single-point illumination devices at the edge of the touch surface 300 of the optical touch system 30, for example, on the touch surface 300. A row of single-point illumination devices is added to the second side 302, and a column of single-point illumination devices is added to the third side 303 of the touch surface 300. Each of the single-point light-emitting devices described above can be implemented by using a light-emitting diode. Of course, when a row of single-point illumination devices is disposed on the same side of the four sides of the touch surface 300 as a light-emitting device or a light-reflecting device, the arrangement can be performed in an up-and-down arrangement, as shown in FIG. 3B. Give an example. Figure 3B shows one of the configurations of a single row of single point illumination devices. In FIG. 3, reference numeral 350 denotes a light-emitting device disposed on the third side 303 of the touch surface 300, and reference numeral 390 denotes a light-emitting module disposed on the third side 303 of the touch surface 300. The lighting module 390 has a plurality of single-point lighting devices 391 arranged in a row. Preferably, the position of each single-point light-emitting device 391 in the light-emitting module 390 corresponds to the position of one of the photosensitive elements 323 of the photosensitive device 321 . In addition, the arrangement positions of the light-emitting module 390 and the light-emitting device 350 may also be reversed.

Of course, if the arrangement of the single-point light-emitting devices 391 in the light-emitting module 390 is dense enough, the light-emitting device 350 in FIG. 3B can be omitted, as long as the position of the single-point light-emitting device 391 in the light-emitting module 390 is disposed. Corresponding to the arrangement position of each photosensitive element 323 of the photosensitive device 321 is illustrated in Fig. 3C. Fig. 3C is an embodiment for explaining the arrangement position of the single-point light-emitting device and the arrangement position of the photosensitive elements. In FIG. 3C, reference numeral 321 denotes a photosensitive device disposed on the first side 301 of the touch surface 300, and the photosensitive device 321 has photosensitive elements 323 arranged in a line. In addition, the mark 390 represents A light emitting module disposed on the third side 303 of the touch surface 300, the light emitting module 390 having a single point light emitting device 391 arranged in a row. As shown in FIG. 3C, the arrangement positions of the partial single-point light-emitting devices 391 in the light-emitting module 390 correspond to the arrangement positions of the photosensitive elements 323 of the photosensitive device 321 .

Second embodiment:

4 is a schematic diagram of an optical touch system in accordance with another embodiment of the present invention. In FIG. 4, the same reference numerals as those in FIG. 3A are denoted by the same reference numerals. The optical touch system 40 shown in FIG. 4 also uses two object sensing modules (labeled 310 and 420 respectively), and the optical touch system 40 shown in FIG. 4 and the optical touch shown in FIG. 3A. The difference between the system 30 and the two object sensing devices in the object sensing module 420 of the optical touch system 40 is implemented by the image sensing device 421 and the image sensing device 422, respectively.

In this example, the extension line of the center of the sensing range of the image sensing device 311 forms a first angle (for example, an angle of 135 degrees) with the extension line of the center of the sensing range of the image sensing device 312. In addition, the image sensing devices 421 and 422 are respectively disposed on the first side 301 to the fourth side 304 of the touch surface 300, and the extension line of the sensing range center of the image sensing device 421 and the image sensing device 422 The extension line at the center of the sensing range forms a second angle (eg, a 90 degree angle). However, the configuration of the image sensing devices 421 and 422 is not intended to limit the present invention. It should be understood by those skilled in the art that the image sensing devices 421 and 422 can be respectively disposed on the first side of the touch surface 300. Any two adjacent sides of 301 to fourth side 304.

As shown in FIG. 4, the processing circuit 430 is electrically coupled to the image sensing devices 311, 312, 421, and 422. In the actual operation mode, when the objects 331 and 332 are adjacent to the touch surface 300, the processing circuit 430 calculates the possible coordinates of the two objects 331 and 332 according to the image of the object sensed by the object sensing module 310. Position as a first candidate coordinate group. In addition, the processing circuit 430 calculates the possible seats of the two objects 331 and 332 according to the object information sensed by the object sensing module 420. The target position is used as the second candidate coordinate group. In detail, the image sensing device 421 in the object sensing module 420 can sense the objects 331 and 332 along the sensing paths 421-1 and 421-2, respectively, and the image sensing device 422 can respectively follow The sensing devices 331 and 422-2 sense the objects 331 and 332, so the processing circuit 430 treats each object image sensed by the image sensing devices 421 and 422 as an object information to further The object information is used to obtain the sensing routes 421-1, 421-2, 422-1, and 422-2, and the intersections of the sensing routes 421-1, 421-2, 422-1, and 422-2 are calculated accordingly. In order to be the second candidate coordinate group.

Since in the first candidate coordinate group and the second candidate coordinate group, only the intersection of some sensing routes is the actual coordinate position of the objects 331 and 332, and the others are ghost points, so the processing circuit 430 can further obtain the first The intersection of the candidate coordinate group and the second candidate coordinate group is to treat the intersection as the actual coordinate position of the objects 331 and 332. In this way, the optical touch system 40 is not affected by ghost points and misjudges the coordinate positions of the objects 331 and 332.

In addition, in the preferred hardware implementation of the present invention, the optical touch system 40 may further include at least three illumination devices, each of which may be disposed on one of the first side 301 to the fourth side 304. And used to illuminate the image sensing devices 311 and 312. In this example, the optical touch system 40 employs three illumination devices in total, and two of the illumination devices (indicated by 440 and 450, respectively) are disposed on the second side 302 and the third side 303, respectively, and the remaining A light emitting device (not shown) is disposed in superposition with the image sensing device 421. In other words, when either side of the touch surface 300 is configured with both the light emitting device and the image sensing device, the light emitting device needs to be superimposed with the image sensing device. In addition, each of the light-emitting devices 40 can be directly replaced by a light-reflecting device, as long as the light-reflecting devices can reflect light to the image sensing devices 311 and 312. Of course, in the case where each of the light-emitting devices 40 is replaced by a light-reflecting device, each of the image sensing devices needs to have an infrared light-emitting device, for example, having infrared rays. Light-emitting diode. In addition, each of the image sensing devices described above also needs to have an infrared filter device that can only pass infrared rays, for example, an infrared filter, so that each image sensing device can obtain through the infrared filter device. The image on the touch surface 300.

In other implementations, the object sensing module 310 of the optical touch system 40 can calculate the first of the two objects in addition to the first set of image information including the objects 331 and 332. A candidate coordinate group. The object sensing module 420 is only used to detect the second group of image information including the two objects. The processing circuit 430 is configured to select at least part of coordinates from the first candidate coordinate group as the actual coordinate positions of the two objects according to the second set of image information.

Third embodiment:

FIG. 5 is a schematic diagram of an optical touch system according to still another embodiment of the present invention. In FIG. 5, the same reference numerals as those in FIG. 4 are denoted by the same reference numerals. The optical touch system 50 shown in FIG. 5 differs from the optical touch system 40 shown in FIG. 4 in that the optical touch system 50 is in addition to the existing image sensing devices 311, 312, 421, and 422. Image sensing devices 511 and 512 are also included. The image sensing devices 511 and 512 form a third object sensing module. The image sensing device 511 is disposed at a corner where the third side 303 and the fourth side 304 of the touch surface 300 intersect, and thus is adjacent to a corner where the image sensing device 311 is disposed, and the image sensing device 512 is disposed at The corner where the second side 302 of the touch surface 300 intersects the third side 303 is thus adjacent to the corner where the image sensing device 312 is disposed.

In this example, the extension line of the center of the sensing range of the image sensing device 311 and the extension line of the center of the sensing range of the image sensing device 312 form a first angle (for example, an angle of 135 degrees). The extension line of the center of the sensing range of the image sensing device 421 and the extension line of the center of the sensing range of the image sensing device 422 form a second angle (for example, a 90 degree angle). In addition, the extension line of the center of the sensing range of the image sensing device 511 forms a third angle (for example, a 45 degree angle) with the extension line of the center of the sensing range of the image sensing device 311. Similarly, the extension line of the sensing range center of the image sensing device 512 and the sensing of the image sensing device 312 The extension line at the center of the range also forms a third angle.

As shown in FIG. 5, the processing circuit 530 is electrically coupled to the image sensing devices 311, 312, 421, 422, 511, and 512. In detail, when the objects 331 and 332 are adjacent to the touch surface 300, the processing circuit 530 calculates the sensing routes 311-1, 311-2, and 312 according to the image of the objects sensed by the image sensing devices 311 and 312. The intersection of -1 and 312-2 to serve as the first candidate coordinate group. In addition, the processing circuit 530 calculates the intersection of the sensing routes 421-1, 421-2, 422-1, and 422-2 according to the image of the object sensed by the image sensing devices 421 and 422, so as to be a second candidate. Coordinate group. In addition, the processing circuit 530 also calculates the sensing routes 311-1, 311-2, 511-1 and 511 according to the object image sensed by the image sensing device 311 and the object image sensed by the image sensing device 511. The intersection of -2 to serve as the third candidate coordinate group. In other embodiments, the processing circuit 530 can also be modified to calculate the intersection of the sensing route according to the object image sensed by the image sensing device 312 and the image sensing device 512 sensed. Three candidate coordinate groups.

Since only two intersection points in the first candidate coordinate group, the second candidate coordinate group and the third candidate coordinate group are the actual coordinate positions of the objects 331 and 332, and the others are ghost points, the processing circuit 530 can further obtain The intersection of the first candidate coordinate group, the second candidate coordinate group, and the third candidate coordinate group is to treat the intersection as the actual coordinate position of the objects 331 and 332. In this way, the optical touch system 50 is not affected by ghost points and misjudges the coordinate positions of the objects 331 and 332.

In addition, in the preferred hardware implementation of the present invention, the optical touch system 50 further includes four illumination devices, each of which is disposed on the first side 301 to the fourth side 304 of the touch surface 300. One of them is used to illuminate the image sensing devices 311 and 312. Two of the light-emitting devices (not shown) are respectively disposed on the second side 302 and the third side 303 of the touch surface 300, respectively. The image sensing device on the same side is superimposed. In addition, this light Each of the light-emitting devices in the touch system 50 can also be directly replaced by a light-reflecting device, as long as each of the light-reflecting devices can reflect light to the image sensing devices 311 and 312. Of course, in the case that each of the light-emitting devices 50 is replaced by a light-reflecting device, each of the image sensing devices needs to have an infrared light-emitting device, for example, an infrared light-emitting diode. In addition, each of the image sensing devices described above also needs to have infrared rays passing through only one of the infrared filtering devices, for example, having infrared filters, so that each of the image sensing devices can be obtained through the infrared filtering device. The image on the touch surface 300.

In summary, the present invention solves the aforementioned problems, mainly establishes a plurality of coordinate systems in an optical touch system, and uses different coordinate systems to generate different ghost points, so that the candidate coordinate groups generated by each coordinate system can mutually confirm each other. Whether each candidate coordinate is a ghost point or an actual coordinate, for example, the intersection of the candidate coordinate groups generated by each coordinate system is directly used as the actual coordinate position.

While the present invention has been described in its preferred embodiments, the present invention is not intended to limit the invention, and the present invention may be modified and modified without departing from the spirit and scope of the invention. The scope of protection is subject to the definition of the scope of the patent application.

40‧‧‧Optical touch system

300‧‧‧ touch surface

301‧‧‧ first side

302‧‧‧ second side

303‧‧‧ third side

304‧‧‧ fourth side

310, 420‧‧‧ Object sensing module

311, 312, 421, 422‧‧‧ image sensing devices

311-1, 311-2, 312-1, 312-2, 421-1, 421-2, 422-1, 422-2‧‧‧ Sensing route

331, 332‧‧‧ objects

333, 334, 335, 336 ‧ ‧ ghost points

430‧‧‧Processing circuit

440, 450‧‧‧ illuminating devices

Claims (15)

An optical touch system includes: a touch surface; a first object sensing module, comprising: a first image sensing device; and a second image sensing device, wherein the first image sensing device The extension line at the center of the sensing range forms a first angle with the extension line of the center of the sensing range of the second image sensing device; and a second object sensing module includes: a first object sensing device, configured An edge of the touch surface; and a second object sensing device disposed at an edge of the touch surface, wherein an extension line of the center of the sensing range of the first object sensing device and the second object sense An extension line at a center of the sensing range of the device forms a second angle; and a processing circuit electrically coupled to the first object sensing module and the second object sensing module, when the first object and the first object When the second object is adjacent to the touch surface, the processing circuit calculates the possible coordinate positions of the objects according to the image of the object sensed by the first object sensing module, so as to be a first candidate coordinate group, the processing The circuit is also based on the The object information sensed by the two object sensing modules is used to calculate possible coordinate positions of the objects, so as to be a second candidate coordinate group, and further obtain an intersection of the first candidate coordinate group and the second candidate coordinate group. The first image sensing device and the second image sensing device are respectively disposed at two adjacent corners of the touch surface, and the first object is configured as the actual coordinate position of the object; The sensing device and the second object sensing device are respectively disposed on adjacent sides of the touch surface, and one side of the adjacent two sides is connected to the adjacent two corners, each image sensing device and each The viewing angles of the object sensing devices are different, and at least one of the first/second image sensing devices And at least one of the first/second object sensing devices is configured to sense light emitted by the same light source. The optical touch system of claim 1, wherein the processing circuit obtains an intersection of the first candidate coordinate group and the second candidate coordinate group, and includes determining whether the second candidate coordinate group has Any coordinate position is a distance from one of the target positions in the first candidate coordinate group is less than a predetermined distance, and each pair of coordinate positions having a distance less than the preset distance is regarded as the first candidate coordinate group and the coordinate position The intersection of the second candidate coordinate group. The optical touch system of claim 1, wherein the processing circuit obtains an intersection of the first candidate coordinate group and the second candidate coordinate group, and includes determining whether the first candidate coordinate group has Any coordinate position is a distance from one of the target positions in the second candidate coordinate group is less than a predetermined distance, and each pair of coordinate positions having a distance less than the preset distance is regarded as the first candidate coordinate group and the coordinate position The intersection of the second candidate coordinate group. The optical touch system of claim 1, wherein the touch surface has a quadrangular shape, and the quadrilateral has a first side, a second side, a third side, and a first four sides. The optical touch system of claim 4, wherein the first image sensing device is disposed at a corner where the first side intersects the fourth side, and the second image sensing device is disposed at a corner where the first side intersects the second side. The optical touch system of claim 5, wherein the first object The sensing device and the second object sensing device are respectively implemented by a first photosensitive device and a second photosensitive device, and the first photosensitive device and the second photosensitive device are respectively disposed on the first side to the fourth side Each of the photosensitive devices has a plurality of photosensitive elements, each photosensitive element is configured to sense the light of the touch surface, and accordingly output a sensing signal, and the processing circuit is The sensing signals output by the first photosensitive device and the second photosensitive device are regarded as the object information, and the possible coordinate positions of the objects are calculated to serve as the second candidate coordinate group. The optical touch system of claim 6, further comprising at least three illuminating devices, each illuminating device being disposed on one of the first side to the fourth side, and configured to face the touch The light-emitting device and the photosensitive device are superimposed on the same side. The optical touch system of claim 6, further comprising at least three reflective devices, each of the reflective devices being disposed on one of the first side to the fourth side and configured to reflect light The reflective device and the photosensitive device are disposed on the same side of the touch surface, and each of the image sensing devices has an infrared illuminating device and only one infrared ray filtering device is passed through, and each image is The sensing device obtains an image of the touch surface through its infrared filter device. The optical touch system of claim 5, wherein the first object sensing device and the second object sensing device are implemented by a third image sensing device and a fourth image sensing device, respectively. The third image sensing device and the fourth image sensing device are respectively disposed on any two adjacent sides of the first side to the fourth side, and the processing circuit is the third image sensing device The sensed object image and the object image sensed by the fourth image sensing device are used as the object information, and the possible coordinate positions of the objects are calculated accordingly Set to serve as the second candidate coordinate group. The optical touch system of claim 9, further comprising at least three illuminating devices, each illuminating device being disposed on one of the first side to the fourth side, and configured to face the touch The light-emitting device and the image sensing device are superimposed on the same side. The optical touch system of claim 9, further comprising at least three reflective devices, each of the reflective devices being disposed on one of the first side to the fourth side and configured to reflect light The reflective device and the image sensing device are disposed on the same side of the touch surface, and each of the image sensing devices has an infrared illuminating device and only one infrared ray filtering device can pass through the infrared ray filtering device. An image sensing device obtains an image of the touch surface through its infrared filter device. The optical touch system of claim 9, further comprising a third object sensing module, the third object sensing module comprising: a fifth image sensing device disposed in the third a corner intersecting the fourth side; and a sixth image sensing device disposed at a corner where the second side intersects the third side. The optical touch system of claim 5, wherein the first object sensing device is implemented by the first image sensing device or the second image sensing device, the second object sensing device The third image sensing device is disposed at a corner where the second side intersects the third side, or is disposed at the third side and intersects the fourth side. a corner, and the corner of the third image sensing device is disposed adjacent to a corner of the image sensing device as the first object sensing device, and the corner The circuit device uses the object image sensed by the image sensing device of the first object sensing device and the object image sensed by the third image sensing device as the object information, and calculates the objects according to the object information. Possible coordinate position to serve as the second candidate coordinate group. The optical touch system of claim 13, further comprising four illumination devices, each of the illumination devices being disposed on one of the first side to the fourth side and configured to face the touch The surface emitting light and the light emitting device on the same side are superimposed on the image sensing device. The optical touch system of claim 13, further comprising four reflective devices, each reflective device being disposed on one of the first side to the fourth side and configured to reflect light to The touch surface and the reflective device on the same side are superimposed with the image sensing device, and each image sensing device has an infrared illuminating device and only one infrared ray filtering device can pass through, and each The image sensing device obtains an image of the touch surface through its infrared filter device.