TW201445373A - Optical touch system and optical touch method - Google Patents

Abstract

The invention provides an optical touch system including: a first transmitter transmitting a first light signal; a sensor sensing a second light signal; and a touch pen including a receiver receiving the first light signal; a second transmitter for transmitting the second light signal; and a processing unit enabling the second transmitter when the receiver receives the first light signal.

Description

Optical touch system and optical touch method

The present invention relates to an optical touch system and an optical touch method, and particularly relates to an optical touch system and an optical touch method capable of achieving a power saving effect.

Currently, an active whiteboard pen used in an optical touch system transmits an optical sensing module by emitting light of a specific wavelength (for example, infrared rays). Thereby, the optical sensing module can recognize the presence of the electronic whiteboard pen, calculate the touch position, and determine the current state of the electronic whiteboard pen (for example, the color of the stroke, etc.). However, under this architecture, the electronic whiteboard pen cannot detect whether it is being used. Therefore, it is necessary to continuously emit the light of the specific wavelength to ensure that it can be correctly recognized by the optical sensing module during use, but the continuous emission of light causes The whiteboard pen has a fast power consumption.

In view of this, the present invention provides an optical touch system and an optical touch method, which can automatically stop emitting light representing the whiteboard pen itself when the electronic whiteboard pen is not used, thereby achieving a power saving effect.

An embodiment of the present invention provides an optical touch system including: a first transmitter that emits a first optical signal; a sensor that senses a second optical signal; and a stylus that includes: a receiver receiving the first optical signal; a second transmitter for transmitting the second optical signal; and a processing unit that activates the second transmitter when the receiver receives the first optical signal.

In the above optical touch system, the first transmitter transmits the first optical signal along a touch surface, so that the receiver receives the first light when the stylus approaches the touch surface. Optical signal.

In the above optical touch system, the first optical signal emitted by the first transmitter has a specific blinking frequency, and the processing unit determines, according to the specific blinking frequency, the light received by the receiver as the The first optical signal.

In the above optical touch system, the stylus further includes: a filter disposed outside the receiving surface of the receiver to allow only light of a wavelength range of the first optical signal to enter the receiver.

In the above optical touch system, the optical touch system is an electronic whiteboard device and the stylus is an electronic whiteboard pen, the stylus is switchable to a plurality of stroke modes, and the processing unit controls the second emission The second optical signal is emitted by a plurality of blinking frequencies corresponding to a plurality of stroke patterns.

The optical touch system further includes: a touch computing module, determining a current stroke mode of the stylus according to the blinking frequency of the second optical signal; and a display panel, the touch track of the stylus The stroke corresponding to the current stroke mode is displayed on the top.

In the above optical touch system, when the stylus power is too low, the control unit controls the second transmitter to emit the second optical signal of a specific blinking frequency.

In the above optical touch system, at least one of the first optical signal and the second optical signal is an infrared light signal.

Another embodiment of the present invention provides an optical touch method, including: providing a first optical signal along a touch surface; and touching the touch surface with a stylus having a transmitter and a a receiver, when the receiver receives the first optical signal, causing the transmitter to emit a second optical signal; and determining a position of the stylus according to the second optical signal.

The optical touch method further includes: when the receiver does not receive the first optical signal, stopping the transmitter to cause the stylus to be in a power saving state.

According to the optical touch system and the optical touch method described above, when the receiver on the electronic whiteboard pen receives the light signal emitted by the system, the emitter of the electronic whiteboard pen is activated to emit light representing the electronic whiteboard pen itself; When receiving the light signal from the system, the emitter of the electronic whiteboard pen is stopped, and the light representing the electronic whiteboard pen itself is not emitted, thereby achieving the effect of saving electricity.

1‧‧‧ stylus (electronic whiteboard pen)

2‧‧‧Optical sensing module

3‧‧‧ touch surface

4‧‧‧ display panel

5‧‧‧Touch computing module

11‧‧‧ Receiver

12‧‧‧Infrared emitter

13‧‧‧Processing unit

14‧‧‧Infrared filter

21‧‧‧Infrared emitter

22‧‧‧ Sensor

IR1, IR2‧‧‧ infrared signal

1 is a perspective view of an optical touch system in accordance with an embodiment of the present invention.

Figure 2 is an architectural diagram of the optical touch system of Figure 1.

Fig. 3 is a flow chart showing the action of the stylus when the optical touch system of Fig. 2 is used in an electronic whiteboard device.

1 is a perspective view of an optical touch system in accordance with an embodiment of the present invention. The optical touch system of the present invention comprises: a stylus 1, an optical sensing module 2, a touch surface (for example, glass) 3, and a display panel 4.

The stylus 1 is provided with a receiver 11 and an infrared emitter 12 at a position close to the pen tip, and the receiver 11 is configured to receive the infrared emitted by the optical sensing module 2 The line signal, the infrared emitter 12 is used to transmit another infrared signal to the optical sensing module 2. The optical sensing module 2 continuously emits infrared rays along the touch surface 3 to detect whether the stylus pen 1 is close to the touch surface 3. If the stylus pen 1 is close to the touch surface 3, the optical sensing module 2 is transmitted. The infrared signal is sent back to the optical sensing module 2, so that the optical sensing module 2 can determine the current state and the touch position of the stylus 1. When the optical touch system is used in an electronic whiteboard device, the stylus pen 1 is equivalent to an electronic whiteboard pen, and can be written or drawn on the touch surface 3, according to the color or line thickness set by the stylus pen 1, The display panel 4 displays the corresponding color or line thickness and the like on the track of the stylus pen 1 .

Next, the architecture of the optical touch system of the present invention will be explained in more detail. Figure 2 is an architectural diagram of the optical touch system of Figure 1. In the second drawing, the same elements as those in Fig. 1 will be denoted by the same reference numerals. As shown in FIG. 2, the optical sensing module 2 has an infrared emitter 21 and a sensor 22. The stylus 1 has a processing unit 13 in addition to the aforementioned receiver 11 and infrared emitter 12. In this embodiment, an infrared filter 14 may be additionally provided to cover the receiver 11 and the infrared emitter 12. The optical touch system further includes a touch computing module 5 for calculating a touch position. The function of each component will be described below in accordance with the order of the actions.

First, the infrared emitter 21 emits an infrared signal IR1 having a specific flicker frequency along the touch surface 3. When the stylus 1 approaches the touch surface 3, the receiver 11 can receive the infrared signal IR1. At this time, the receiver 11 converts the infrared light signal IR1 into an electrical signal output to the processing unit 13. The processing unit 13 determines whether the frequency of the infrared signal emitted by the optical sensing module 2 is consistent according to the frequency information included in the electrical signal. When the judgment frequency is the same, the processing unit 13 controls the infrared emitter 12 of the stylus pen 1 to emit the infrared signal IR2; The frequency is inconsistent, and the processing unit 13 controls the infrared emitter 12 to stop emitting the infrared signal IR2.

When the optical touch system is used in an electronic whiteboard device, the stylus 1 is equivalent to an electronic whiteboard pen, so that the user can be switched to different stroke states, for example, different colors, line thicknesses, line styles, and the like. The processing unit 13 can control the infrared emitters 12 of the stylus 1 to emit infrared signals IR2 of different blinking frequencies according to different states, so that each blinking frequency corresponds to a state of the stylus. What is more, the infrared signal IR2 of a certain flicker frequency can be corresponding to the state that the stylus 1 is too low, so that the state of the low battery can be reported to the optical touch system.

After receiving the infrared signal IR2, the sensor 22 of the optical sensing module 2 converts the optical signal into an electrical signal output to the touch computing module 5. The touch computing module 5 calculates the touch position according to the incident direction of the two optical sensing modules 2 according to the infrared signal IR2, and determines the state of the stylus according to the blinking frequency of the infrared signal IR2. When the optical touch system is used in the electronic whiteboard device, the display panel 4 displays the corresponding color or line thickness on the trajectory of the stylus 1 according to the color of the stylus 1 or the thickness of the line.

According to the above optical touch system, the stylus pen 1 emits the infrared signal IR2 only when it is used near the touch surface 3, and does not emit the infrared signal IR2 when the stylus pen 1 is not used, thereby achieving power saving. Effect. On the other hand, the infrared filter 14 is provided outside the receiver 11 and the infrared emitter 12 to isolate light of a non-infrared wavelength (for example, sunlight or a halogen bulb), so that the amount of calculation by the processing unit 13 can be reduced.

Finally, the operation flow of the optical touch system will be described. Figure 3 The action flow chart of the stylus when the optical touch system of FIG. 2 is used for the electronic whiteboard device. In step S301, the electronic whiteboard pen (stylus 1) stands by and is maintained in the power saving state.

Next, proceeding to step S302, it is determined whether the receiver 11 receives the infrared signal. If both of the infrared signals are received, the process proceeds to step S303, otherwise, the process returns to the power saving state of step S301.

In step S303, the processing unit 13 determines whether the frequency of the infrared signal received by the receiver 11 is consistent with the infrared signal IR1. If the frequency is the same, the infrared signal is confirmed to be emitted by the infrared emitter 21 of the optical sensing module 2, and the step S304 is advanced. If the frequencies do not match, the process returns to the power saving state of step S301.

In step S304, the processing unit 13 controls the infrared emitter 12 to transmit the infrared signal number IR2 of the specific blinking frequency corresponding to the state according to the current state of the electronic whiteboard pen (including the stroke color, thickness, pattern, power shortage, etc.) to optical sensing. Module 2. After a set delay time elapses after step S304, the electronic whiteboard pen returns to step S302 to re-determine whether the electronic whiteboard pen is being used.

According to the optical touch system and the operation flow described above, it is possible to automatically stop the emission of the infrared signal when the electronic whiteboard pen is not used, thereby achieving the effect of power saving. In addition, although the present invention uses an infrared signal as an optical signal for communication between the stylus and the optical sensing module, optical signals of other wavelengths can also be applied to the architecture of the present invention, and the present invention does not use an infrared signal. limit.

Although the invention has been described in the above embodiments, it is not limited thereto. Furthermore, the scope of the patent application must be broadly construed to include the present invention without departing from the spirit and scope of the invention. Examples and other variations. For example, the calculation of the infrared emitter and the sensor of the optical sensing module can be respectively set at different positions, and the calculation of the touch position is not limited to the embodiment according to the returned infrared signal, and the touch object can be illuminated through other light sources. Then judge according to the shadow in the sensor.

1‧‧‧ stylus (electronic whiteboard pen)

2‧‧‧Optical sensing module

3‧‧‧ touch surface

4‧‧‧ display panel

5‧‧‧Touch computing module

11‧‧‧ Receiver

12‧‧‧Infrared emitter

13‧‧‧Processing unit

14‧‧‧Infrared filter

21‧‧‧Infrared emitter

22‧‧‧ Sensor

IR1, IR2‧‧‧ infrared signal

Claims (10)

An optical touch system includes: a first transmitter that emits a first optical signal; a sensor that senses a second optical signal; and a stylus that includes: a receiver that receives the first light a second transmitter for transmitting the second optical signal; and a processing unit that activates the second transmitter when the receiver receives the first optical signal. The optical touch system of claim 1, wherein the first emitter emits the first optical signal along a touch surface such that the stylus approaches the touch surface, the receiver The first optical signal will be received. The optical touch system of claim 1, wherein the first optical signal emitted by the first transmitter has a specific blinking frequency, and the processing unit determines the receiver according to the specific blinking frequency. The received light is the first optical signal. The optical touch system of claim 1, wherein the stylus further comprises: a filter disposed outside the receiving surface of the receiver to allow only light of a wavelength range of the first optical signal to be incident. The receiver. The optical touch system of claim 1, wherein the optical touch system is an electronic whiteboard device and the stylus is an electronic whiteboard pen, the stylus is switchable to a plurality of stroke modes, The processing unit controls the second transmitter to emit a plurality of flicker frequencies corresponding to the plurality of stroke patterns The second optical signal. The optical touch system of claim 5, further comprising: a touch computing module, determining a current stroke mode of the stylus according to a blinking frequency of the second optical signal; and a display panel, A stroke corresponding to the current stroke pattern is displayed on the touch track of the stylus. The optical touch system of claim 1, wherein the control unit controls the second transmitter to emit the second optical signal of a specific flicker frequency when the stylus is too low. The optical touch system of claim 7, wherein at least one of the first optical signal and the second optical signal is an infrared light signal. An optical touch method includes: providing a first optical signal along a touch surface; and touching the touch surface with a stylus, the stylus having a transmitter and a receiver; when the receiver receives The first optical signal causes the transmitter to emit a second optical signal; and the position of the stylus is determined according to the second optical signal. The optical touch method of claim 9, further comprising: when the receiver does not receive the first optical signal, stopping the transmitter to cause the stylus to be in a power saving state.