Method and apparatus for calibrating an optical touchpad surface

Abstract

The embodiment of the present application provides a kind of optical touchpad surface calibration method and device, the method comprises: the trajectory image of the light source at the bottom of calibration tooling that is attached to the movement of touchpad surface is collected;The position of light source trajectory image in image acquisition range is calibrated as the position of touchpad surface in image acquisition range.The present application can effectively improve touch precision, avoid the false touch phenomenon, and further effectively improve user operation experience.

Description

Technical Field

[0001] This invention relates to the field of interactive technology, and specifically to an optical touch panel calibration method and apparatus. Background Technology

[0002] With the development of human-computer interaction technology, touch devices, as input devices that replace or supplement keyboards and mice, have been widely used in education, training, office work, exhibitions, and other occasions or fields. Touch devices include optical touch devices, infrared touch devices, and capacitive touch devices, among which optical touch devices are particularly widely used in multimedia interactive technologies due to their superior performance, such as fast response speed and high precision.

[0003] like Figure 1 As shown, the optical touch device includes a touchpad 1 (e.g., a blackboard), two or more image acquisition devices 2 (e.g., cameras), and a recognition light source 3. Here, we will use two image acquisition devices 2 as an example: one image acquisition device 2 is installed at each of the two upper corners of the touchpad 1. In order to acquire image data of the object being touched (e.g., chalk) on the touchpad surface, the touchpad surface needs to be illuminated by the recognition light source 3, and the touchpad 1 needs to be placed within the acquisition range of the two image acquisition devices 2. Figure 2 As shown, the image acquisition range of each image acquisition device 2 is approximately a rectangular area.

[0004] Based on the above settings, although it can be determined that the touchpad is within the image acquisition range, the specific position of the touchpad surface within the image acquisition range cannot be determined. This results in the image acquisition device misjudging that the touch object is in contact with the touchpad surface when it is within the image acquisition range, but there is a certain distance between it and the touchpad surface. That is, when the touch object is in a floating state, the image acquisition device mistakenly judges that the touch object has contacted the touchpad surface and thus executes a response, causing false triggering, such as continuous writing before or after putting down the pen. Summary of the Invention

[0005] In view of this, embodiments of the present invention provide an optical touch panel calibration method and apparatus to solve the above-mentioned technical problems.

[0006] To achieve the above technical objectives, embodiments of the present invention provide an optical touch panel calibration method, the improvement of which includes:

[0007] Acquire the trajectory image of the bottom light source of the calibration fixture that moves against the touch panel surface;

[0008] The position of the light source trajectory image within the image acquisition range is calibrated as the position of the touch panel surface within the image acquisition range.

[0009] To achieve the above technical objectives, this invention provides an optical touch panel calibration device, which is improved in that it includes a calibration fixture and a processor, wherein a light source is provided at the bottom of the calibration fixture;

[0010] The processor is used to acquire the trajectory image of the bottom light source of the calibration fixture that moves against the touch panel surface through the image acquisition device, and to calibrate the position of the light source trajectory image within the image acquisition range as the position of the touch panel surface within the image acquisition range.

[0011] Compared with the prior art, the present invention has the following advantages due to the adoption of the above technical solutions:

[0012] This invention sets the bottom surface of a calibration fixture to fit against the touch panel surface, and simultaneously places a light source at the bottom of the calibration fixture, making the light source very close to the touch panel surface. Thus, when the calibration fixture moves on the touch panel surface, the trajectory of the light source captured by the image acquisition device can be regarded as the position of the touch panel surface within the image acquisition range. This position is then calibrated. When the touch object is within this position range, it is determined that the touch object is in contact with the touch panel surface, and a preset response is executed. Otherwise, it is determined that the touch object is in a floating state. Therefore, it can effectively improve touch accuracy, avoid false triggering, and thus effectively improve the user experience.

[0013] This invention is easy to operate, low in cost, and can be widely applied in the field of interactive technology. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the structure of an optical touch device in the prior art;

[0015] Figure 2 yes Figure 1 Schematic diagram of the image acquisition range of the image acquisition device;

[0016] Figure 3 This is a flowchart of one embodiment of the optical touch panel calibration method of the present invention;

[0017] Figure 4 This is a schematic diagram showing the position of the trajectory image of the bottom light source of the calibration fixture of the present invention within the image acquisition range;

[0018] Figure 5 This is a schematic diagram showing the position of the calibration line of the present invention within the image acquisition range;

[0019] Figure 6 This is a schematic diagram of the predetermined trajectory of the calibration tooling of the present invention;

[0020] Figure 7 This is a structural diagram of one embodiment of the optical touch panel calibration device of the present invention;

[0021] Figure 8 yes Figure 7 A structural diagram of one embodiment of the tooling used in the bidding process. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the embodiments and accompanying drawings. Here, the illustrative embodiments and descriptions of this invention are used to explain the invention, but are not intended to limit the invention.

[0023] like Figure 3 As shown, an embodiment of the present invention provides an optical touch panel calibration method, including:

[0024] Acquire the trajectory image of the bottom light source of the calibration fixture that moves against the touch panel surface;

[0025] The position of the light source trajectory image within the image acquisition range is calibrated as the position of the touch panel surface within the image acquisition range.

[0026] In practice, the calibration fixture can be held by hand, ensuring its bottom surface is in contact with the touch panel. While moving the fixture, the image acquisition device simultaneously captures the trajectory image of the light source at the bottom of the calibration fixture. The position of the light source's trajectory image within the image acquisition range is shown below. Figure 4 As shown, the white light spot represents the trajectory image of the light source.

[0027] Because the bottom surface of the calibration fixture is in contact with the touch panel surface, and a light source is installed at the bottom of the calibration fixture, the position of the light source is very close to the touch panel surface. Therefore, when the calibration fixture moves on the touch panel surface, the light source trajectory collected by the image acquisition device can be regarded as the position of the touch panel surface within the image acquisition range. This position is calibrated. When the touch object is within this position range, it is determined that the touch object is in contact with the touch panel surface, and a preset response is executed. Otherwise, it is determined that the touch object is in a suspended state.

[0028] Clearly, the above settings can effectively improve touch accuracy, avoid accidental triggering, and thus effectively improve the user experience.

[0029] In some embodiments, the optical touch panel calibration method further includes:

[0030] The light source trajectory image is processed to obtain the brightest point in each column of pixels. The calibration line connecting these points is then used as the position of the touchpad surface within the image acquisition range. The position of the calibration line within the image acquisition range is as follows: Figure 5 As shown.

[0031] Because the light source trajectory image includes the halo and reflections from the touch panel, it is wider than the actual light source. At the same time, since the light emitted by the light source is the brightest, corresponding to the brightest point in the light source trajectory image, the actual position of the light source can be determined by connecting the brightest points in each column of pixels in the light source trajectory image. This position is closer to the touch panel surface, thus effectively improving the accuracy of the calibration results.

[0032] In some embodiments, the optical touch panel calibration method further includes:

[0033] The calibration fixture moves along a predetermined trajectory to fit the touchpad surface, such as... Figure 6 As shown, the predetermined trajectory is a continuous trajectory covering the field of view of the two image acquisition devices.

[0034] Clearly, moving the calibration fixture along the predetermined trajectory ensures that all areas of the touch panel can be calibrated within the image acquisition range, and also ensures that the movement of the calibration fixture is within the acquisition range of the image acquisition device. Therefore, it can effectively improve the integrity and efficiency of the calibration results.

[0035] In some embodiments, the optical touch panel calibration method further includes:

[0036] When a calibration signal is detected, the identification light source is turned off.

[0037] Since the identification light source can interfere with the light source at the bottom of the calibration fixture, the identification light source is automatically turned off when a calibration signal is detected. This can effectively improve the accuracy of the calibration results, as well as the degree of automation and calibration efficiency.

[0038] Based on the same inventive concept, embodiments of the present invention also provide an optical touch panel calibration device, such as... Figure 7 As shown, it includes a calibration fixture 4 and a processor 5, wherein a light source is provided at the bottom of the calibration fixture 4;

[0039] The processor 5 is used to acquire the trajectory image of the bottom light source of the calibration fixture 4 that moves against the touch panel surface through the image acquisition device 2, and to calibrate the position of the light source trajectory image within the image acquisition range as the position of the touch panel surface within the image acquisition range.

[0040] In specific operation, the calibration fixture 4 can be held by hand, ensuring that the bottom surface of the calibration fixture 4 is in contact with the touch panel surface, while moving the calibration fixture 4. At the same time, the image acquisition device 2 acquires the trajectory image of the light source at the bottom of the calibration fixture 4. The position of the light source trajectory image within the image acquisition range is as follows: Figure 4 As shown, the white light spot represents the trajectory image of the light source.

[0041] Since the bottom surface of the calibration fixture 4 is in contact with the touch panel surface, and a light source is provided at the bottom of the calibration fixture 4, the position of the light source is very close to the touch panel surface. Therefore, when the calibration fixture 4 moves on the touch panel surface, the light source trajectory collected by the image acquisition device 2 can be regarded as the position of the touch panel surface within the image acquisition range. This position is calibrated. When the touch object is within this position range, it is determined that the touch object is in contact with the touch panel surface, and a preset response is executed. Otherwise, it is determined that the touch object is in a suspended state.

[0042] Clearly, the above settings can effectively improve touch accuracy, avoid accidental triggering, and thus effectively improve the user experience.

[0043] In some embodiments, a ring light source is provided at the bottom of the calibration fixture 4 to facilitate image acquisition by the image acquisition device 2.

[0044] In some embodiments, a magnetic sheet is provided on the inner side of the bottom surface of the calibration fixture 4 so that the calibration fixture 4 can be attached to the touch panel surface.

[0045] In some embodiments, such as Figure 8 As shown, the calibration fixture 4 includes a housing 41, a circuit board, a data cable 42, several LEDs, a light-transmitting ring 43, and a bottom cover. The circuit board is installed inside the housing 41. One end of the circuit board is connected to the data cable 42, and the other end of the data cable 42 extends outside the housing 41 for connection with the processor 5 during use. Several LEDs are fixedly arranged at intervals around the bottom surface of the circuit board. A light-transmitting ring 43 is fitted around the outside of the LEDs. The top of the light-transmitting ring 43 is fixedly connected to the housing 41, and a bottom cover is detachably installed on the bottom surface of the light-transmitting ring 43.

[0046] In some embodiments, the processor 5 includes a detection module, which is used for:

[0047] When the data line 42 of the calibration fixture 4 is detected to be connected to the processor 5, it is identified as a calibration signal, and the identification light source is turned off according to the calibration signal.

[0048] Since the identification light source can interfere with the light source at the bottom of the calibration fixture 4, the identification light source is automatically turned off when a calibration signal is detected. This can effectively improve the accuracy of the calibration results, as well as the degree of automation and calibration efficiency.

[0049] In some embodiments, the processor 5 includes a scribing module, which is used for:

[0050] The light source trajectory image is processed to obtain the brightest point in each column of pixels. The calibration line connecting these points is then used as the position of the touchpad surface within the image acquisition range. The position of the calibration line within the image acquisition range is as follows: Figure 5 As shown.

[0051] Because the light source trajectory image includes the halo and reflections from the touch panel, it is wider than the actual light source. At the same time, since the light emitted by the light source is the brightest, corresponding to the brightest point in the light source trajectory image, the actual position of the light source can be determined by connecting the brightest points in each column of pixels in the light source trajectory image. This position is closer to the touch panel surface, thus effectively improving the accuracy of the calibration results.

[0052] Obviously, those skilled in the art should understand that the modules or steps of the above-described embodiments of the present invention can be implemented using general-purpose computing devices. They can be centralized on a single computing device or distributed across a network of multiple computing devices. Optionally, they can be implemented using computer-executable program code, thereby storing them in a storage device for execution by a computing device. In some cases, the steps shown or described can be performed in a different order than those presented here, or they can be fabricated as separate integrated circuit modules, or multiple modules or steps can be fabricated as a single integrated circuit module. Thus, the embodiments of the present invention are not limited to any particular hardware and software combination.

[0053] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, various modifications and variations can be made to the embodiments of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for calibrating an optical touch panel, characterized in that, The method comprises: Collecting a track image of the light source on the bottom of the calibration tool moving along the touchpad surface; Marking the position of the light source track image in the image collection range as the position of the touchpad surface in the image collection range, and calibrating the position. When the touch object is located within the position range, it is determined that the touch object is in contact with the touchpad surface, and a preset response is executed.

2. The method of claim 1, wherein, The method further comprises: Processing the light source track image to obtain the brightest point in each column of pixels of the light source track image, and marking a calibration line connecting the points as the position of the touchpad surface in the image collection range.

3. The method of claim 1, wherein, The method further comprises: Moving the calibration tool along a predetermined track on the touchpad surface, wherein the predetermined track is a continuous track covering the field of view angles of the two image collection devices.

4. The method of claim 1, wherein, The method further comprises: When a calibration signal is detected, turning off the identification light source.

5. An optical touchpad surface calibration apparatus, characterized by, The calibration tool and a processor are included, wherein the calibration tool is provided with a light source at the bottom thereof; The processor is configured to collect a track image of the light source on the bottom of the calibration tool moving along the touchpad surface by an image collection device, and mark the position of the light source track image in the image collection range as the position of the touchpad surface in the image collection range, and calibrate the position. When the touch object is located within the position range, it is determined that the touch object is in contact with the touchpad surface, and a preset response is executed.

6. The apparatus of claim 5, wherein, The calibration tool is provided with a ring-shaped light source at the bottom thereof.

7. The apparatus of claim 5, wherein, A magnetic sheet is provided inside the bottom surface of the calibration tool.

8. The apparatus of claim 5, wherein, The calibration tool comprises a shell, a circuit board, a data line, a plurality of LED lights, a light-transmitting ring, and a bottom cover. The shell is provided with the circuit board therein. One end of the data line is connected to the circuit board, and the other end of the data line extends out of the shell for connection with the processor during use. The circuit board is provided with a plurality of LED lights fixed thereon at intervals in the circumferential direction. The LED lights are provided with the light-transmitting ring outside. The light-transmitting ring is fixedly connected to the top of the shell. The bottom surface of the light-transmitting ring is detachably provided with the bottom cover.

9. The apparatus of claim 8, wherein, The processor comprises a detection module configured to identify a calibration signal when the data line of the calibration tool is connected to the processor, and to turn off the identification light source according to the calibration signal.

10. The apparatus of claim 5, wherein, The processor comprises a line drawing module configured to process the light source track image to obtain the brightest point in each column of pixels of the light source track image, and to mark a calibration line connecting the points as the position of the touchpad surface in the image collection range.

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