CN102902420B - Sensing system - Google Patents

Abstract

The invention relates to a sensing system which is suitable for sensing an indicator and calculating the position of the indicator. The sensing system comprises a panel, a reflection element, an image sensor and a processor. The panel has a first plane and a first area located on the first plane. The first area is quadrilateral and has a first edge, a second edge, a third edge and a fourth edge which are connected in sequence. The reflecting element is configured on the first edge and is positioned on the first plane. A second plane of the reflection element is a mirror reflection surface which is substantially vertical to the first plane and reflects the first area to form a second area. The image sensor is arranged on a corner where the third edge and the fourth edge intersect and is positioned on the first plane. The sensing range of the image sensor covers the first area and the second area. The processor is electrically connected with the image sensor. The sensing system of the invention has lower production cost.

Description

sensing system

divisional application

The present invention is a divisional application for a patent application with the application number 200910006251.X and the name "sensing system" filed by the same applicant on February 6, 2009.

technical field

The present invention relates to a sensing system, and more particularly to a sensing system with a reflective element.

Background technique

The touch system (touch system) has been disclosed by many related patents, such as US Pat. No. 4,782,328 and US Pat. No. 6,803,906. The touch systems disclosed in the above two patents each require at least two sensors, which makes the cost of production of the touch systems disclosed in the above patents relatively high. One of the above two patents will be used for illustration below.

Please refer to FIG. 1 , which is a schematic diagram of a conventional touch screen system. The touch screen system (touch screen system) 100 disclosed in U.S. Patent No. 4,782,328 includes a panel (panel) 110, a first photosensor (photosensor) 120, a second photosensor 130 and A processor (processor) 140 . The panel 110 has a touch screen area 112 whose shape is a rectangle. The first light sensor 120 and the second light sensor 130 are disposed at opposite ends of one side (boundary) 112 a of the touch screen area 112 , and the first light sensor 120 and the second light sensor 130 The sensing ranges respectively cover the touch screen area 112 . In addition, the first light sensor 120 and the second light sensor 130 are electrically connected to the processor 140 .

When a pointer 150 touches the above-mentioned touch screen area 112, the first light sensor 120 and the second light sensor 130 are respectively along a first sensing path (sensing path) 162 and a first The second sensing route 164 senses the indicator 150 . The processor 140 calculates the position of the pointer 150 according to the first sensing route 162 and the second sensing route 164 .

However, the conventional touch screen system 100 must have two light sensors 120 and 130 , so the production cost of the conventional touch screen system 100 is relatively high.

Contents of the invention

The purpose of the present invention is to overcome the defects of the existing touch screen system and provide a sensing system with a new structure. The technical problem to be solved is to lower the production cost.

The purpose of the present invention and the solution to its technical problems are achieved by adopting the following technical solutions. A sensing system according to the present invention is suitable for sensing an indicator and calculating the position of the indicator. The sensing system includes a panel, an image sensor, a first linear light source, a second linear light source, a reflection element and a processor. The panel has a first plane and a first side, a second side, a third side and a fourth side connected in sequence, and the first side, the second side, the third side and the fourth side connected in sequence The edge surrounds a first region. The image sensor is disposed at a corner where the third side and the fourth side intersect. The sensing range of the image sensor covers the first side and the second side. The first linear light source is arranged on the second side and emits light on the first plane. The second linear light source is arranged on the third side and emits light on the first plane. The reflective element is arranged on the first side and located on the first plane. A second plane of the reflection element is perpendicular to the first plane, and the second plane is a specular reflection surface. The processor is electrically connected to the image sensor. When the pointer is close to the first area, the pointer will block a first light beam directed to the image sensor, thereby generating a real image in the image captured by the image sensor, and the pointer will block a second light beam directed to the reflective element, And a virtual image is generated in the image captured by the image sensor. The indicator shielding the first light includes shielding the first light from the first linear light source directly directed to the image sensor, or shielding the first light when the first linear light source or the second linear light source directs the first light to the reflective element, resulting in the second A light cannot enter the image sensor. The pointer shielding the second light includes shielding the second light emitted from the first linear light source or the second linear light source to the reflective element, so that the second light cannot enter the image sensor through the reflection of the reflective element. The processor calculates the position of the pointer according to the positions of the real image and the virtual image in the captured image.

In an embodiment of the present invention, the first area is a rectangle.

In an embodiment of the present invention, the processor has information of a first distance " D1 " between the first side and the third side, and calculating the position of the pointer by the processor includes the following steps. First, determine the first angle "A1" between the line connecting the corner and the real image and the third side. Next, a second angle "A2" between the line connecting the corner and the virtual image and the third side is determined. Then, divide the twice of D1 by the sum of tanA1 and tanA2 to calculate a second distance “D2” between the pointer and the fourth side.

In an embodiment of the present invention, the first area is a non-rectangular quadrangle, and the sensing system further includes a third linear light source disposed on the fourth side and emitting light on the first plane. The pointer shielding the second light includes shielding the second light from the first linear light source or the second linear light source or the third linear light source to the reflective element, so that the second light cannot be reflected by the reflective element and enter the image sensor. The processor has information of a first distance " D3 " between a first imaginary line passing through the corner and parallel to the first side and the first side. Calculating the position of the pointer by the processor includes the following steps. First, determine the first angle "A3" between the line connecting the corner and the real image and the first imaginary line. Next, a second angle "A4" between the line connecting the corner and the virtual image and the first imaginary line is determined. Then, divide twice the D3 by the sum of tanA3 and tanA4 to calculate a second distance “D4” between a second imaginary line passing through the corner and perpendicular to the first side and the indicator.

The purpose of the present invention and the solution to its technical problems are achieved by adopting the following technical solutions. A sensing system according to the present invention is suitable for sensing an indicator and calculating the position of the indicator. The sensing system includes a panel, an image sensor, a first light source, a first reflector, a second reflector, a reflective element and a processor. The panel has a first plane and a first side, a second side, a third side and a fourth side connected in sequence, and the first side, the second side, the third side and the fourth side connected in sequence The edge surrounds a first region. The image sensor is disposed at a corner where the third side and the fourth side intersect. The sensing range of the image sensor covers the first side and the second side. The first light source is located next to the image sensor. The first reflector is disposed on the second side and has a first retro-reflective surface. The second reflector is disposed on the third side and has a second retro-reflective surface. The reflective element is arranged on the first side and located on the first plane. A second plane of the reflection element is perpendicular to the first plane, and the second plane is a specular reflection surface. The processor is electrically connected to the image sensor. When the pointer is close to the first area, the pointer will block a first light emitted by the first light source to the first reflector or reflective element to generate a real image in the image captured by the image sensor, and the pointer will block the reflection element. A second light of the first light source is reflected to generate a virtual image in the image captured by the image sensor. The indicator shielding the first light includes shielding the first light from the first light source directly to the first reflector, or shielding the first light from the first light source from directly to the reflective element, so that the first light cannot pass through the first reflector or The retro-reflection of the second reflector returns to the image sensor. Wherein, the pointer shielding the second light includes shielding the second light after the reflective element reflects the second light, so that the second light cannot return to the image sensor through the retro-reflection of the first reflector or the second reflector. The processor calculates the position of the pointer according to the positions of the real image and the virtual image in the captured image.

In an embodiment of the present invention, the first area is a rectangle.

In an embodiment of the present invention, the first area is a non-rectangular quadrilateral. The sensing system further includes a third reflector disposed on the fourth side and having a third retro-reflective surface. The indicator shielding the second light includes shielding the second light after the reflective element reflects the second light, so that the second light cannot return to the image sensor through the retro-reflection of the first reflector, the second reflector or the third reflector.

In an embodiment of the present invention, the first light source is suitable for emitting invisible light. The image sensor has an image sensing window and a filter. The filter is arranged in front of the image sensing window, and the filter filters other light except the invisible light so that the invisible light passes through the filter. In addition, the first light source is an infrared light emitting diode, and the filter is an infrared light pass filter.

Compared with the prior art, the present invention has obvious advantages and beneficial effects. With the above technical solution, the sensing system of the present invention has at least the following advantages and beneficial effects: By configuring the reflective element and the image sensor, the processor of the sensing system in the embodiment of the present invention can calculate the position of the indicator . Therefore, compared with the conventional technology, the sensing system of this embodiment can use one image sensor, so that the production cost of the sensing system of this embodiment is lower.

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, and in conjunction with the accompanying drawings, the detailed description is as follows.

Description of drawings

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

FIG. 2 is a schematic perspective view of a sensing system according to the first embodiment of the present invention.

FIG. 3 is a schematic top view of the sensing system of FIG. 2 in operation.

FIG. 4 is a schematic diagram of the processor in FIG. 3 calculating the location of the indicator.

FIG. 5 is a schematic diagram of an image sensing window of the image sensor in FIG. 3 .

FIG. 6 is a schematic top view of a sensing system in operation according to a second embodiment of the present invention.

FIG. 7 is a schematic diagram of the processor of FIG. 6 calculating the location of the indicator.

FIG. 8 is another schematic diagram of the processor in FIG. 6 calculating the position of the indicator.

FIG. 9 is a schematic diagram of an image sensing window of the image sensor of FIG. 6 .

FIG. 10 is a schematic perspective view of a sensing system according to a third embodiment of the present invention.

FIG. 11 is a schematic perspective view of a sensing system according to a fourth embodiment of the present invention.

FIG. 12 is a schematic top view of a sensing system in operation according to a fifth embodiment of the present invention.

FIG. 13 is a schematic top view of a sensing system in operation according to a sixth embodiment of the present invention.

100: Touch Screen System

110, 210, 310, 410, 610, 710: panel

112: Touch screen area

112a, 212a, 212b, 212c, 212d, 312a, 312b, 312c, 312d: sides

612b, 612c, 612d, 712a, 712b, 712c, 712d: side

120, 130: light sensor

140, 260, 360: Processor

150, 270, 370, 470, 570: counters

162, 164, 282, 284, 382, 384, 386: sensing route

200, 300, 400, 500, 600, 700: Sensing system

212, 212’, 312, 312’, 412, 512, 612, 612’, 712, 712’: area

214, 222, 314, 414, 614, 714: plane

220, 320, 420, 520, 620, 720: reflective element

230, 240, 330, 340, 390: Linear light source

212d’, 230’, 240’, 270’, 330’, 340’, 370’, 390’: mirror image

430’, 612d’, 630’, 640’, 730’, 740’, 790’: mirror image

250, 350, 450, 550, 650, 750: Image sensor

252, 352, 452, 652, 752: Image sensing window

252a, 252b, 352c: dark lines 254, 354: bright areas

272, 272’: Tip 430, S1, S2: Light source

456, 656: filter 472: reflective surface

572: Lighting device 630, 640, 790: Reflector

632, 642, 792: Retro-reflective surface A1, A2, A3, A4, A5: Angle

C1, C2: Corners D1, D2, D3, D4, D5: Distances

L1, L2: imaginary line W1: width.

Detailed ways

In order to further explain the technical means and effects that the present invention adopts to achieve the intended purpose of the invention, the specific implementation, structure, features and effects of the sensing system proposed according to the present invention will be described below in conjunction with the accompanying drawings and preferred embodiments. Detailed description.

[first embodiment]

FIG. 2 is a schematic perspective view of a sensing system according to a first embodiment of the present invention, and FIG. 3 is a schematic top view of the sensing system in FIG. 2 in operation. Referring to FIG. 2 and FIG. 3 , the sensing system 200 is adapted to sense an indicator 270 and calculate the position of the indicator 270 (see below for details). The sensing system 200 includes a panel 210 , a reflective element 220 , a first linear light source 230 , a second linear light source 240 , an image sensor 250 and a processor 260 .

The aforementioned panel 210 is, for example, a whiteboard or a touch screen, which has a first plane 214 and a first region 212 located on the first plane 214 . The shape of the first area 212 is a quadrilateral, such as a rectangle, and the first area 212 has a first side 212a, a second side 212b, a third side 212c and a fourth side 212d connected in sequence.

The aforementioned reflective element 220 is disposed on the first side 212 a and located on the first plane 214 . A second plane 222 of the reflective element 220 is substantially perpendicular to the first plane 214, the second plane 222 is a specular reflection surface, and the second plane 222 reflects the first area 212 to form a second area 212'. The reflective element 220 is, for example, a plane mirror, but not limited thereto.

The above-mentioned first linear light source 230 is disposed on the second side 212b and on the first plane 214, and the first linear light source 230 forms a second mirror image 230' with respect to the reflective element 220.

The above-mentioned second linear light source 240 is disposed on the third side 212c and located on the first plane 214, and the second linear light source 240 forms a third mirror image 240' relative to the reflective element 220. The fourth side 212d forms a fourth mirror image 212d' with respect to the reflective element 220 . The reflective element 220 , the first linear light source 230 , the second linear light source 240 and the fourth side 212 d surround a first region 212 . The reflective element 220, the second mirror image 230', the third mirror image 240' and the fourth mirror image 212d' surround a second region 212'.

The aforementioned image sensor 250 is disposed at a corner C1 where the third side 212c and the fourth side 212d intersect and is located on the first plane 214. The sensing range of the image sensor 250 covers the first area 212 and the second area. 212'. The first linear light source 230, the second mirror image 230' and the third mirror image 240' are located within the sensing range of the image sensor 250. In addition, the processor 260 is electrically connected to the image sensor 250 .

The operation of the sensing system 200 of this embodiment will be described below. FIG. 4 is a schematic diagram of the processor in FIG. 3 calculating the location of the pointer, and FIG. 5 is a schematic diagram of the image sensing window of the image sensor in FIG. 3 . Please refer to FIG. 3, FIG. 4 and FIG. 5, when the indicator 270 (see FIG. 2) is adjacent to the first region 212, and the indicator 270 forms a first mirror image 270' with respect to the reflective element 220, so that the indicator 270 and the second When a mirror image 270' is located within the sensing range of the image sensor 250, and when a part of the pointer 270 adjacent to the first region 212, a part of the first mirror image 270' adjacent to the second region 212' and the image sensor When 250 is not collinear, the image sensor 250 senses the pointer 270 and the first mirror image 270 ′, and the processor 260 calculates the position of the pointer 270 . In other words, the image sensor 250 of this embodiment senses the indicator 270 along a first sensing route 282 and senses the first image 270 ′ along a second sensing route 284 , and the processor 260 according to the first sensing route 284 A sensing route 282 and a second sensing route 284 calculate the position of the pointer 270 .

It must be noted here that, in this embodiment, the part of the pointer 270 adjacent to the first region 212 is a tip 272 of the pointer 270 (see FIG. 2 ), and the part of the first mirror image 270 ′ adjacent to the second region 212 ' is a tip 272' of the first mirror image 270'.

In detail, in this embodiment, the image sensor 250 has an image sensing window 252 and a lens (not shown). The lens is disposed in front of the image sensing window 252, so that the image sensing range of the image sensor 250 can cover the first area 212 and the second area 212'. When the indicator 270 is not adjacent to the first area 212 , the light emitted by the first linear light source 230 , the second mirror image 230 ′ and the third mirror image 240 ′ will form a brighter beam on the image sensing window 252 The bright zone 254 is the primary sensing zone. When the pointer 270 is close to the first area 212, the image sensor 250 senses the pointer 270 along the first sensing route 282, and a first dark stripe (obscure strip) will appear in the bright area 254 on the image sensing window 252. ) 252a, and the image sensor 250 outputs a first electrical signal. The processor 260 receives the first electrical signal and determines a first angle A1 between the first sensing line 282 and the third side 212c according to the position of the first dark stripe 252a on the image sensing window 252 . In other words, the processor 260 can have the information of the corresponding relationship between the position of the dark pattern on the image sensing window 252 and the angle between the sensing line and the third side 212c in a built-in manner, so that the above-mentioned determination of the third side 212c A work of angle A1 is performed.

Similarly, the image sensor 250 will sense the first image 270' along the second sensing route 284, the bright area 254 on the image sensing window 252 will have a second dark fringe 252b, and the image sensor 250 will output A second electrical signal. The processor 260 receives the second electrical signal and determines a second angle A2 between the second sensing line 284 and the third side 212c according to the position of the second dark stripe 252b on the image sensing window 252 . It should be noted here that the stronger the brightness of the first linear light source 230 and the second linear light source 240 is, the more obvious the first dark lines 252 a and the second dark lines 252 b on the image sensing window 252 are.

In addition, the processor 260 may have information of a first distance D1 between the first side 212a and the third side 212c in a built-in manner. In this embodiment, the third side 212c is the X-axis as the Cartesian coordinate system, the fourth side 212d is the Y-axis as the Cartesian coordinate system, and the coordinates of the corner C1 are (0, 0 ). The X coordinate of the indicator 270 is a second distance D2 between the indicator 270 and the fourth side 212d, and the midpoint of the indicator 270 and the first mirror image 270' is located on the first side 212a, so D1 is equal to (D2 ×tanA1+D2×tanA2)/2. Therefore, the processor 260 may divide the twice of D1 by the sum of tanA1 and tanA2 to calculate the second distance D2 between the indicator 270 and the fourth side 212d. In other words, the coordinates (D2, D2×tanA1) of the indicator 270 can be obtained through the above calculation method. It must be noted here that the above-mentioned calculation method of the coordinates of the indicator 270 in the rectangular coordinate system is used as an example, and the designer can use other coordinate systems to calculate the coordinates of the indicator according to the design requirements. The present invention is based on This is not limited.

Through the configuration of the reflective element 220 and the image sensor 250 , the processor 260 of the sensing system 200 of this embodiment can calculate the position of the indicator 270 . Therefore, compared with the conventional technology, the sensing system 200 of the present embodiment can use one image sensor 250 , so that the production cost of the sensing system 200 of the present embodiment is lower.

[Second embodiment]

FIG. 6 is a schematic top view of a sensing system in operation according to a second embodiment of the present invention. FIG. 7 is a schematic diagram of the processor of FIG. 6 calculating the location of the indicator. Please refer to FIG. 6 and FIG. 7 , the difference between the sensing system 300 of the second embodiment of the present invention and the sensing system 200 of the first embodiment is that the sensing system 300 further includes a third linear light source 390 located at The shape of the first region 312 at the first plane 314 of the panel 310 is a non-rectangular quadrilateral.

The above-mentioned third linear light source 390 is disposed on the fourth side 312d of the first region 312, and the third linear light source 390 forms a fourth mirror image 390' with respect to the reflective element 320. The reflective element 320 (arranged on the first side 312a of the first area 312), the first linear light source 330 (arranged on the second side 312b of the first area 312), the second linear light source 340 (arranged on the second side of the first area 312 The three sides 312 c ) and the third linear light source 390 surround the first area 312 .

The above-mentioned reflective element 320, the second mirror image 330' formed by the first linear light source 330 relative to the reflective element 320, the third mirror image 340' and the fourth mirror image 390' formed by the second linear light source 340 relative to the reflective element 320 surround The second region 312'. In addition, the image sensor 350 is disposed at the corner C2 where the third side 312c and the fourth side 312d intersect, and the sensing range of the image sensor 350 covers the first area 312 and the second area 312'. The first linear light source 330, the second mirror image 330', the third mirror image 340' and the fourth mirror image 390' are located within the sensing range of the image sensor 350. Additionally, indicator 370 forms a first mirror image 370' with respect to reflective element 320.

The operation of the sensing system 300 of this embodiment will be described below. In this embodiment, the first imaginary line L1 passing through the corner C2 and parallel to the first side 312a is used as the X-axis of the Cartesian coordinate system, and the second imaginary line L2 passing through the corner C2 and perpendicular to the first side 312a is used as a rectangular seat The Y axis of the coordinate system, and the coordinates of the corner C2 are (0, 0). The processor 360 may have the information of the first distance D3 between the first imaginary line L1 and the first side 312a in a built-in manner.

When the pointer 370 is adjacent to the first region 312 and the pointer 370 forms a first mirror image 370 ′ relative to the reflective element 320 , so that the pointer 370 and the first mirror image 370 ′ are located within the sensing range of the image sensor 350 , and When a part of the indicator 370 adjacent to the first region 312 and a part of the first mirror image 370 ′ adjacent to the second region 312 ′ are not collinear with the image sensor 350 , the image sensor 350 first senses The pointer 370 is sensed along the route 382 and the first image 370 ′ is sensed along the second sensing route 384 . Next, the processor 360 determines the first angle A3 between the first sensing route 382 and the first imaginary line L1 according to the first sensing route 382 and the second sensing route 384, and the second sensing route 384 and the second sensing route 384 respectively. A second angle A4 between an imaginary line L1. Then, the processor 360 divides twice the D3 by the sum of tanA3 and tanA4 to calculate the second distance D4 between the second imaginary line L2 and the pointer 370 . Therefore, the coordinates (D4, D4×tanA3) of the indicator 370 can be obtained through the above calculation method.

It must be noted here that, the sensing method of the image sensor 350 and the method of determining the angle of the processor 360 in this embodiment can refer to the relevant description of the first embodiment, so details are not repeated here.

FIG. 8 is another schematic diagram of the processor of FIG. 6 calculating the position of the pointer, and FIG. 9 is a schematic diagram of the image sensing window of the image sensor of FIG. 6 . Please refer to FIG. 6, FIG. 8 and FIG. 9. In this embodiment, when the pointer 370 is not adjacent to the first area 312, the first linear light source 330, the second mirror 330', the third mirror 340' and the fourth The light emitted by the mirror image 390 ′ will form a bright area 354 with higher brightness on the image sensing window 352 (see also FIG. 6 ), which is the main sensing area. When the portion of the indicator 370 adjacent to the first region 312 and the portion of the first mirror image 370 ′ adjacent to the second region 312 ′ are collinear with the image sensor 350 , the image sensor 350 moves along a third sensor. The measuring line 386 (ie, the second imaginary line L2 ) senses the size of the indicator 370 . It should be noted here that the processor 360 of this embodiment can have a built-in relationship between the size of the pointer 370 located on the third sensing route 386 and the length of the third distance D5 between the pointer 370 and the corner C2. information of the corresponding relationship, and the processor 360 calculates the position of the indicator 370 according to the size of the indicator 370 .

In other words, the closer the indicator 370 is to the image sensing window 352 of the image sensor 350 (that is, the smaller the third distance D5), the width W1 of the third dark fringes 352c appearing in the bright area 354 on the image sensing window 352 will be bigger. The corresponding relationship between the size of the width W1 and the length of the third distance D5 may be pre-built in the processor. Therefore, when the pointer 370, the first mirror image 370' and the image sensor 350 are collinear, the processor 360 calculates the corresponding third distance D5 according to the size of the pointer 370.

In this embodiment, the processor 360 can further have a third angle A5 between the third sensing route 386 and the first imaginary line L1 in a built-in manner, so the coordinates of the indicator 370 (D5×cosA5, D5×sinA5) can be obtained. In this embodiment, the third angle A5 is 90 degrees.

[Third embodiment]

FIG. 10 is a schematic perspective view of a sensing system according to a third embodiment of the present invention. Please refer to FIG. 2 and FIG. 10 , the difference between the sensing system 400 and the sensing system 200 of the third embodiment of the present invention is that the sensing system 400 omits the configuration of the first linear light source 230 and the second linear light source 240 . The sensing system 400 includes a first light source 430 disposed above the first plane 414 of the panel 410 and outside the first area 412 . The first light source 430 forms a second mirror image 430' with respect to the reflective element 420. The first light source 430 and the second mirror image 430' are located outside the sensing range of the image sensor 450. The indicator 470 has a reflective surface 472 , and the reflective material of the reflective surface 472 complies with, for example, the European standard EN471, but not limited thereto.

The first light source 430 is suitable for emitting invisible light, such as infrared light, with a wavelength of about 940 nanometers (nm). The first mirror image (not shown) of the indicator 470 relative to the reflective element 420 is formed by the first light source 430 illuminating the reflective surface 472 of the indicator 470 . The image sensor 450 may have a filter 456 disposed in front of the image sensing window 452 . The indicator 470 can reflect the invisible light to the filter 456 , and the filter 456 filters other light so that the image sensing window 452 receives the invisible light reflected by the indicator 470 . In addition, the image sensor 450 can also sense the first mirror image (not shown) of the pointer 470 .

It must be noted here that the first region 412 may be a non-rectangular quadrilateral, but it is not shown in the drawing.

[Fourth Embodiment]

FIG. 11 is a schematic perspective view of a sensing system according to a fourth embodiment of the present invention. Please refer to FIG. 2 and FIG. 11 , the difference between the sensing system 500 and the sensing system 200 of the fourth embodiment of the present invention is that the sensing system 500 can omit the configuration of the first linear light source 230 and the second linear light source 240 . The pointer 570 has a light emitting device 572 , and the first mirror image (not shown) is formed by the light emitted by the light emitting device 572 . The image sensor 550 can sense the pointer 570 and its first mirror image (not shown) formed relative to the reflective element 520 .

It must be noted here that the first region 512 may be a non-rectangular quadrilateral, but it is not shown in the drawing.

[Fifth Embodiment]

FIG. 12 is a schematic top view of a sensing system in operation according to a fifth embodiment of the present invention. Please refer to FIG. 3 and FIG. 12 , the difference between the sensing system 600 and the sensing system 200 of the fifth embodiment of the present invention is that the sensing system 600 can omit the configuration of the first linear light source 230 and the second linear light source 240 . The sensing system 600 further includes a first light source S1 , a first reflector 630 and a second reflector 640 . The first light source S1 is located beside the image sensor 650 . The first light source S1 is, for example, an infrared light emitting diode, suitable for emitting invisible light, such as infrared light. The image sensor 650 may have a filter 656 , such as an infrared light pass filter, which allows infrared light to pass and is disposed in front of the image sensing window 652 .

The first reflector 630 is disposed on the second side 612 b of the first region 612 of the panel 610 and is located on the first plane 614 of the panel 610 . The first reflector 630 forms a second mirror image 630' with respect to the reflective element 620. The first reflector 630 has a first retro-reflective surface 632, and the first retro-reflective surface 632 is suitable for reflecting the light emitted by the first light source S1. That is, the material of the first reflector 630 may be a retro-reflective material.

The second reflector 640 is disposed on the third side 612 c of the first region 612 of the panel 610 and is located on the first plane 614 of the panel 610 . The second reflector 640 forms a third mirror image 640' with respect to the reflective element 620. The second reflector 640 has a second retro-reflective surface 642, and the second retro-reflective surface 642 is suitable for reflecting the light emitted by the first light source S1. That is to say, the material of the second reflector 640 can also be a retro-reflective material.

The fourth side 612d of the first region 612 of the panel 610 forms a fourth mirror image 612d' with respect to the reflective element 620 . The reflective element 620 , the first reflector 630 , the second reflector 640 and the fourth side 612 d surround the first region 612 . The reflective element 620, the second mirror image 630', the third mirror image 640' and the fourth mirror image 612d' surround the second region 612'. The first reflector 630, the second mirror image 630' and the third mirror image 640' are located within the sensing range of the image sensor 650.

The first light source S1 such as an infrared LED emits infrared light, and the first retro-reflective surface 632 of the first reflector 630 and the second retro-reflective surface 642 of the second reflector 640 reflect the infrared light. In other words, the functions of the first retro-reflective surface 632 and the second retro-reflective surface 642 reflecting infrared light are the same as those of the first linear light source 230 and the second linear light source 240 in the first embodiment, so details are omitted here. Therefore, the pointer (not shown) and its first mirror image (not shown) will respectively form a first dark line (not shown) and a second dark line (not shown) on the image sensing window 652 of the image sensor 650 not shown), related descriptions can refer to the content of the first embodiment, and will not be repeated here.

[Sixth embodiment]

FIG. 13 is a schematic top view of a sensing system in operation according to a sixth embodiment of the present invention. Please refer to FIG. 12 and FIG. 13, the difference between the sensing system 700 of the sixth embodiment of the present invention and the sensing system 600 of the fifth embodiment is that the sensing system 700 further includes a third reflector 790, and is located The shape of the first region 712 at the first plane 714 of the panel 710 is a non-rectangular quadrilateral.

The third reflector 790 is disposed on the fourth side 712d of the first region 712, and the third reflector 790 forms a fourth mirror image 790' relative to the reflective element 720. The reflective element 720 (arranged on the first side 712a of the first area 712), the first reflector 730 (arranged on the second side 712b of the first area 712), the second reflector 740 (arranged on the second side of the first area 712 The three sides 712 c ) and the third reflector 790 surround the first region 712 . The third reflector 790 has a third retro-reflective surface 792, and the third retro-reflective surface 792 is suitable for reflecting the light emitted by the first light source S2. That is to say, the material of the third reflector 790 can also be a retro-reflective material.

The reflective element 720, the second mirror image 730' formed by the first reflector 730 relative to the reflective element 720, the third mirror image 740' and the fourth mirror image 790' formed by the second reflector 740 relative to the reflective element 720 surround the second Area 712'. The first reflector 730, the second mirror image 730', the third mirror image 740' and the fourth mirror image 790' are located within the sensing range of the image sensor 750.

For example, the first light source S2, which is an infrared light emitting diode, emits infrared light, and the first retro-reflective surface 732 of the first reflector 730, the second retro-reflective surface 742 of the second reflector 740 and the third reflective surface of the third reflector 790 The retro-reflective surface 792 reflects infrared light. In other words, the functions of the first retro-reflective surface 732 , the second retro-reflective surface 742 and the third retro-reflective surface 792 reflecting infrared light are the same as the first linear light source 330 , the second linear light source 340 and the third linear light source in the second embodiment. 390, so I won’t go into details here. Therefore, the pointer (not shown) and its first mirror image (not shown) will respectively form a first dark line (not shown) and a second dark line (not shown) on the image sensing window 752 of the image sensor 750 not shown), related descriptions can refer to the content of the first embodiment and the second embodiment, and will not be repeated here.

In summary, the sensing system of the embodiments of the present invention has at least the following or other advantages. Through the configuration of the reflective element and the image sensor, the processor of the sensing system of the embodiment of the present invention can calculate the position of the pointer. Therefore, compared with the conventional technology, the sensing system of this embodiment can use one image sensor, so that the production cost of the sensing system of this embodiment is lower.

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, can use the technical content disclosed above to make some changes or modify them into equivalent embodiments with equivalent changes, but any content that does not depart from the technical solution of the present invention, according to the present invention Any simple modifications, equivalent changes and modifications made to the above embodiments by the technical essence still belong to the scope of the technical solution of the present invention.

Claims (7)

1. A sensing system adapted to sense an indicator and calculate the position of the indicator, characterized in that it comprises: A panel has a first plane and a first side, a second side, a third side and a fourth side connected in sequence, and the first side, the second side and the third side connected in sequence encloses a first region with the fourth side; an image sensor disposed at a corner where the third side and the fourth side intersect, wherein the sensing range of the image sensor covers the first side and the second side; A first linear light source is arranged on the second side and emits light on the first plane; A second linear light source is arranged on the third side and emits light on the first plane; a reflective element, disposed on the first side and on the first plane, wherein a second plane of the reflective element is perpendicular to the first plane, and the second plane is a specular reflection surface; a processor electrically connected to the image sensor; When the pointer is adjacent to the first area, the pointer will block a first light beam directed to the image sensor, and a real image will be generated in the image captured by the image sensor, and the pointer will block the reflection directed to the image sensor. a second ray of light from the device to generate a virtual image in the image captured by the image sensor; Wherein the pointer shielding the first light includes shielding the first light from the first linear light source directly to the image sensor, or when the first linear light source or the second linear light source directs the first light to the reflection The component shields the first light so that the first light cannot enter the image sensor; Wherein the indicator shielding the second light includes shielding the second light from the first linear light source or the second linear light source to the reflective element, so that the second light cannot enter the image through reflection of the reflective element sensor; The processor calculates the position of the indicator according to the positions of the real image and the virtual image in the captured image. 2. The sensing system according to claim 1, wherein the first area is rectangular. 3. The sensing system according to claim 2, wherein the processor has information of a first distance "D1" between the first side and the third side, and the processor calculates the indication Item locations include: Determine the first angle "A1" between the line connecting the corner and the real image and the third side; determining a second angle "A2" between the corner and the virtual image and the third side; and Divide twice the D1 by the sum of tanA1 and tanA2 to calculate a second distance “D2” between the indicator and the fourth side. 4. A sensing system adapted to sense an indicator and calculate the position of the indicator, characterized in that it comprises: A panel has a first plane and a first side, a second side, a third side and a fourth side connected in sequence, and the first side, the second side and the third side connected in sequence encloses a first region with the fourth side; an image sensor disposed at a corner where the third side and the fourth side intersect, wherein the sensing range of the image sensor covers the first side and the second side; a first light source, located next to the image sensor; a first reflector, configured on the second side, and has a first retro-reflective surface; a second reflector configured on the third side and having a second retro-reflective surface; a reflective element, disposed on the first side and on the first plane, wherein a second plane of the reflective element is perpendicular to the first plane, and the second plane is a specular reflection surface; a processor electrically connected to the image sensor; When the pointer is close to the first area, the pointer will block a first light from the first light source to the first reflector or the reflective element to generate a real image in the image captured by the image sensor, and The indicator will block a second light of the first light source reflected by the reflective element to generate a virtual image in the image captured by the image sensor; Wherein the indicator shielding the first light includes shielding the first light from the first light source directly to the first reflector, or shielding the first light from the first light source directly to the reflective element, so that the first A light cannot return to the image sensor through retro-reflection of the first reflector or the second reflector; Wherein the indicator shielding the second light includes shielding the second light after the reflective element reflects the second light, so that the second light cannot be re-reflected by the first reflector or the second reflector the image sensor; The processor calculates the position of the indicator according to the positions of the real image and the virtual image in the captured image. 5. The sensing system according to claim 4, wherein the first area is rectangular. 6. The sensing system according to claim 4, wherein the first light source is adapted to emit invisible light, the image sensor has an image sensing window and a filter, and the filter is configured on the image The front of the window is sensed, and the filter filters light other than the invisible light such that the invisible light passes through the filter. 7. The sensing system according to claim 6, wherein the first light source is an infrared light emitting diode, and the filter is an infrared light pass filter.