TWI447621B - Touch system - Google Patents

Description

Touch system

The present invention relates to a touch system, and more particularly to an optical touch system.

Many electronic products use a touch panel as an input method. Currently, touch panels on the market mainly include a resistive touch panel, a capacitive touch panel, and a surface acoustic wave touch panel.

The main part of the resistive touch panel is a resistive film screen that is very compatible with the surface of the display. It is a multi-layer composite film with a glass or hard plastic plate as the base layer and a transparent oxidized metal on the surface (transparent conductive). Resistor) Conductive layer, covered with a layer of outer surface hardened, smooth anti-scratch plastic layer, coated with a coating on its inner surface, with many small (less than 1/1000 inch) transparency between them The isolation point separates the two conductive layers from each other. When the finger touches the screen, the two conductive layers have contact at the touch point position, the resistance changes, and signals are generated in both the X and Y directions, and then sent to the touch screen controller. The controller detects this contact and calculates the position of (X, Y). The resistive touch screen is not affected by dust, water and dirt, and can work under severe conditions; however, the metal conductive layer is relatively thin and easy to be brittle, and coating too thick will reduce the light transmittance and is often touched. After a certain period of time, cracks may occur and even deformation may occur.

The capacitive touch panel is provided with a transparent special metal conductive material on the surface of the film. When the finger touches the metal layer, the user and the touch screen surface form a coupling Capacitance, the capacitance of the contact changes, so that the frequency of the oscillator connected to it changes, and the touch position can be determined by measuring the frequency change. Since the capacitance varies with temperature, humidity, or grounding conditions, the stability is poor and drift often occurs.

The surface acoustic wave touch panel is composed of a screen body, a sound wave generator, a reflection stripe, an acoustic wave receiver and a controller. Wherein, the acoustic wave generator sends a surface acoustic wave across the surface of the screen body, and when the finger touches the screen body, the sound wave of the contact is blocked, and the controller determines the position of the contact by analyzing the received sound wave. The surface acoustic wave touch screen is not affected by environmental factors such as temperature and humidity, has high resolution, excellent scratch resistance and long life; high light transmittance and clear image quality; no drift, only installation One time correction; there is a third axis (ie pressure axis) response, currently used in public places. However, surface acoustic waves are absorbed by water, dust, oil, and even liquids of beverages, so they need to be cleaned and maintained frequently.

In view of this, it is necessary to provide a touch system with a simple structure and good overall performance.

A touch system includes a display panel, an infrared light source, a right angle 稜鏡, and an infrared image sensor, the right angle 稜鏡 including a first surface, a second surface, and a third surface, the first surface and the second surface, The third surface has an angle of 45 degrees, the second surface is perpendicular to the third surface, the infrared light source and the infrared image sensor are located on one side of the first surface, and the display panel is disposed adjacent to and parallel to a distance above the third surface and a distance from the third surface is smaller than a deformation variable generated by the deformation, and the infrared light emitted by the infrared light source enters the right angle 通过 through the first surface and is incident on the a third surface, the incident angle of the infrared light on the third surface is greater than or equal to A critical angle at which total reflection occurs, where infrared light is totally reflected on the third surface and incident on the second surface and then exits from the first surface to image on the infrared image sensor.

Preferably, an illumination source is further included, the illumination source being adjacent to the second surface, and light emitted by the illumination source passes through the second surface into the right angle and then exits from the third surface.

A touch system includes a display panel and a plurality of complex infrared light sources, a plurality of right angle 稜鏡, and a plurality of infrared image sensors, wherein the right angle 稜鏡 includes a first surface, a second surface, and a third surface, the first The angle between the surface and the second surface and the third surface is 45 degrees, the second surface is perpendicular to the third surface, and the first surface is adjacent to the second surface of the adjacent right angle ,, the infrared light source And the infrared image sensor is located on one side of the first surface, the display panel is disposed adjacent to and parallel to the third surface, and the distance between the display panel and the third surface is smaller than the deformation of the display panel a shape variable, the infrared light emitted by the infrared light source enters the right angle 通过 through the first surface and is incident on the third surface, and the incident angle of the infrared light on the third surface is greater than or equal to total reflection The critical angle at which the infrared light is totally reflected on the third surface and incident on the second surface and then exits from the first surface to image on the infrared image sensor.

Compared with the prior art, the touch system of the embodiment of the present invention uses an optical component right angle 稜鏡 and an infrared light source to form a touch body, and is similar to a common resistive touch panel, a capacitive touch panel or a surface acoustic wave touch panel. Compared with external factors such as static electricity, it is not afraid of external factors such as static electricity. At the same time, it is not necessary to install sophisticated touch circuits to calculate the coordinates of the touch points. Therefore, the structure is simple and the cost is low; , voltage and static interference, so suitable for various environmental conditions, adapt Strong.

10, 20‧‧‧ touch system

11, 21‧‧‧ display panel

12, 22‧‧‧ right angle 稜鏡

13, 23‧‧‧ Infrared source

14, 24‧‧‧ Infrared image sensor

15, 25‧‧‧ illumination source

16, 26‧‧‧ Signal Processor

17, 27‧‧ ‧ controller

121, 221‧‧‧ first surface

122, 222‧‧‧ second surface

123, 223‧‧‧ third surface

111‧‧‧ outer surface

112‧‧‧ inner surface

1 is a schematic view of a touch system according to a first embodiment of the present invention.

2 is a schematic view of the touch system of the first embodiment of the present invention when it is not in operation.

3 is a schematic view showing the operation of the touch system according to the first embodiment of the present invention.

4 is a schematic view showing the touch system of the second embodiment of the present invention when it is not in operation.

The invention will now be described in further detail with reference to the accompanying drawings.

As shown in FIG. 1 and FIG. 2, the touch system 10 of the first embodiment of the present invention includes a display panel 11, a right angle 稜鏡12, an infrared light source 13, an infrared image sensor 14, an illumination source 15, and signal processing. The controller 16 and the controller 17.

The right angle 稜鏡 12 includes a first surface 121, a second surface 122, and a third surface 123. The second surface 122 is perpendicular to the third surface 123, and the angle between the first surface 121 and the second surface 122 and the third surface 123 is 45 degrees.

The infrared light source 13 and the infrared image sensor 14 are disposed adjacent to the first surface 121. The illumination source 15 is adjacent to the second surface 122. The display panel 11 is disposed adjacent to and parallel to the third surface 123. The display panel 11 has an opposite outer surface 111 and an inner surface 112. The inner surface 112 is adjacent to the third surface 123 and has a smaller distance from the third surface 123 than the deformation of the display panel 11 so that the deformed display panel 11 can be The third surface 123 is in contact.

The infrared light L2 emitted from the infrared light source 13 can be incident on all areas of the third surface 123, and the incident angle of the infrared light L2 at the third surface 123 is greater than or equal to the occurrence of total reflection. Boundary. The infrared light L2 emitted from the infrared light source 13 enters the right angle 稜鏡12 through the first surface 121, is totally reflected on the third surface 123, is incident on the second surface 122 and is then emitted by the first surface 121, and all the outgoing light L2' are Imaging is performed on the infrared image sensor 14. Since the second surface 122 is perpendicular to the third surface 123, the infrared light L2 which is totally reflected at the third surface 123 is also totally reflected on the second surface 122, and the outgoing light L2' is incident on the incident light L2.

After the infrared light L2 incident on different regions of the third surface 123 is totally reflected, the emitted light L2' will be emitted from different regions of the first surface 121, and then imaged in different regions of the infrared image sensor 14, that is, infrared image sensing. Different areas on the display 14 may correspond to different pixels on the display panel 11.

The infrared light source 13 is a light emitting diode or a laser diode, and the infrared image sensor 14 is a Charge Coupled Device (CCD) sensor or a Complementary Metal Oxide Semiconductor (CMOS). Sensor.

The light L1 emitted from the illumination source 15 enters the right angle 稜鏡 12 via the second surface 122, and then exits from the third surface 123 to illuminate the display panel 11 to realize the function of displaying a picture. Of course, if the touch system 10 does not need to display a picture, the illumination source 15 can be omitted.

The signal processor 16 is electrically connected to the infrared image sensor 14 and the controller 17. The signal processor 16 receives the image signal of the infrared image sensor 14 and processes the result, and outputs the processing result to the controller 17.

As shown in FIG. 3, the finger or the stylus contacts the outer surface 111 of the display panel 11 such that the display panel 11 is deformed, and the inner surface 112 of the display panel 11 is made smaller because the distance between the inner surface 112 and the third surface 123 is smaller than the shape variable. Third surface with right angle 稜鏡12 123 contacts, which causes a slight deformation of the third surface 123; at this time, when the incident light L2 entering the right angle 稜鏡 22 from the first surface 121 reaches the light at the contact surface, the incident angle changes so that some infrared light L2 is The incident angle of the third surface 123 is smaller than the critical angle such that the magnitude of the reflected light signal at the contact surface is abrupt. The abrupt reflected light signal reaches the first surface 121 and produces an image signal on the infrared image sensor 14 that is different from the degree of brightness of the unpressed area. The image signal on the infrared image sensor 14 is processed by the signal processor 16 to detect the position of the pressed point, that is, the pixel point, and finally the controller 17 reacts to the corresponding touch and completes the corresponding pressing instruction.

Because the touch system 10 uses the optical element right angle 稜鏡12 and the infrared light source 13 to form a touch body, compared with a common resistive touch panel, a capacitive touch panel or a surface acoustic wave touch panel, the touch system has good transparency. Light, not afraid of external factors such as static electricity; at the same time, there is no need to install sophisticated touch circuits to calculate the coordinates of the touch points, so the structure is simple and the cost is low; and, since the infrared rays are free from current, voltage and static electricity, Therefore, it can be suitable for harsh environmental conditions.

As shown in FIG. 4, the touch system 20 of the second embodiment of the present invention can be applied to a large-screen display device including a larger-sized display panel 21, a signal processor 26, and a controller 27, and the number is five. Right angle 稜鏡 22, infrared light source 23, infrared image sensor 24 and illumination source 25.

Since the size of the display panel 21 is larger than that of the display panel 11, if a right angle 稜鏡22 is used for a large-sized touch display device, the required right angle 稜鏡 size is large, so that the thickness and volume of the touch system 20 are increased. Therefore, in order to reduce the thickness and volume, the present embodiment employs five right-angled turns 22 of relatively small size. Of course, the number of right angles 22 is not limited to five, and an appropriate number may be selected according to the size of the display panel 21, such as two, three, or each pixel of the display panel 21 corresponds to a straight line. Corner 稜鏡 22.

The right angle 22 has a first surface 221 and a second surface 222 and a third surface 223 which are perpendicular to each other. The angle between the first surface 221 and the second surface 222 and the third surface 223 is 45 degrees. The five right angles 22 are linearly arranged, and the five third surfaces 223 are located on the same plane, and the second surface 222 is adjacent to the first surface 221 of the adjacent right angles 22 .

The infrared light source 23 and the infrared image sensor 24 are disposed adjacent to the first surface 221, the illumination source 25 is adjacent to the second surface 222, and the display panel 21 is located above the third surface 223.

When not pressed, the light emitted by the infrared light source 23 enters the right angle 稜鏡22 through the first surface 221, and the total reflection occurs on the third surface 223 and the second surface 222, and finally exits from the first surface 221, and the emitted light is in the infrared image sense. The image is detected on the detector 24; when pressed, the light signal from the infrared light source 23 enters the right angle 稜鏡22 and the light signal reaching the pressing portion is abruptly changed, so that the infrared image sensor 24 is different from the untouched area. The image signal on the infrared image sensor 24 is processed by the signal processor 26 to detect the position of the pressed point. Finally, the controller 27 reacts to the corresponding touch and completes the corresponding pressing command.

Of course, the number of right angles 稜鏡 22 is not limited to five, and may be arranged in a matrix corresponding to the number of pixels of the display panel 21; or, each row of pixels or each column of pixels corresponds to a right angle 稜鏡22.

In summary, the present invention has indeed met the requirements of the invention patent, and has filed a patent application according to law. However, the above description is only a preferred embodiment of the present invention, and it is not possible to limit the scope of the patent application of the present invention. Equivalent modifications or variations made by persons skilled in the art in light of the spirit of the invention are intended to be included within the scope of the following claims.

10‧‧‧ touch system

11‧‧‧ display panel

12‧‧‧right angle

13‧‧‧Infrared source

14‧‧‧Infrared image sensor

15‧‧‧Light source

16‧‧‧Signal Processor

17‧‧‧ Controller

121‧‧‧ first surface

122‧‧‧ second surface

123‧‧‧ third surface

111‧‧‧ outer surface

112‧‧‧ inner surface

Claims (10)

A touch system, comprising: a display panel, an infrared light source, a right angle 稜鏡, and an infrared image sensor, wherein the right angle 稜鏡 includes a first surface, a second surface, and a third surface, the first surface and the second surface The angle between the surface and the third surface is 45 degrees, the second surface is perpendicular to the third surface, the infrared light source and the infrared image sensor are located on one side of the first surface, and the display panel is close to and parallel The infrared light emitted by the infrared light source enters the right angle 通过 through the first surface and is disposed above the third surface and the distance from the third surface is smaller than a deformation of the display panel. Incident on the third surface, an incident angle of the infrared light on the third surface is greater than or equal to a critical angle at which total reflection occurs, and infrared light is totally reflected on the third surface and incident on the second surface and then The first surface is imaged on the infrared image sensor after exiting. The touch system of claim 1, wherein the infrared light source is a light emitting diode or a laser diode. The touch system of claim 1, wherein the infrared image sensor is a charge coupled device sensor or a complementary metal oxide semiconductor sensor. The touch system of any one of claims 1 to 3, further comprising: an illumination light source disposed adjacent to the second surface, the light emitted by the illumination source passing through the first The two surfaces enter the right angle 稜鏡 and then exit from the third surface. The touch system of claim 4, further comprising: a signal processor and a controller, wherein the signal processor is electrically connected to the infrared image sensor and the controller, respectively. A touch system, comprising: a display panel and a plurality of complex infrared light sources, a plurality of right angles, and a plurality of infrared image sensors, wherein the right angle includes a first surface, a second surface, and a third surface, The angle between the first surface and the second surface and the third surface is 45 degrees The second surface is perpendicular to the third surface, the first surface is adjacent to the second surface of the adjacent rectangular corner, and the infrared light source and the infrared image sensor are located on one side of the first surface. The display panel is disposed adjacent to and parallel to the third surface, and the distance between the display panel and the third surface is smaller than a deformation variable generated by the deformation of the display panel, and the infrared light emitted by the infrared light source passes through the a first surface enters the right angle 且 and is incident on the third surface, and an incident angle of infrared light on the third surface is greater than or equal to a critical angle at which total reflection occurs, and infrared light is generated on the third surface Reflecting and incident on the second surface and then exiting the first surface to image on the infrared image sensor. The touch system of claim 6, wherein: the right angle 稜鏡 is linearly arranged. The touch system of claim 6, wherein: the right angle 稜鏡 matrix is arranged. The touch system of any one of claims 6 to 8, wherein: further comprising an illumination source having the same number as the right angle, the illumination source being disposed adjacent to the second surface, the illumination Light emitted by the light source passes through the second surface into the right angle 稜鏡 and then exits from the third surface. The touch system of claim 9, wherein the method further comprises: a signal processor and a controller, wherein the signal processor is electrically connected to the infrared image sensor and the controller, respectively.