KR20110075723A - Compensation method for touch sensitiveness of display device including touch assembly - Google Patents

Abstract

PURPOSE: A method for compensating the touch sensitiveness of a display device is provided to securely sense a touch by compensating a light difference due to the variation of a light incident angle. CONSTITUTION: Light of a specific region is sensed using an infrared camera sensor(S20). A compensated light amount is created by increasing the variation of sensitivity and minimizing the sensitivity of light quantity in an area in which the variation of the light quantity is large(S30). The areal threshold value is determined using the compensated light quantity of an initial state(S40).

Description

Compensation Method for Touch Sensitiveness of Display Device Including Touch Assembly}

The present invention relates to a display device, and more particularly, to a method of compensating for touch sensitivity of a touch assembly integrated display device in which touch sensing is stable by compensating a light quantity difference due to a difference in incidence angle appearing for each position of a retroreflective plate.

In general, a touch panel is one of various methods for configuring an interface between an information communication device using various displays and a user, and an input device that allows a user to interface with a device by directly touching a screen with a hand or a pen. to be.

Since the touch panel is an input device that can be easily used by anyone, men and women by interactively and intuitively touching only the buttons on the display with a finger, it is currently issued by banks and government offices, various medical equipment, tourism and major It is applied in many fields such as institutional guidance and traffic guidance.

The touch panel may be a resistive type touch panel, a microcapacitive touch glass, an ultrasonic wave touch glass, or an infrared type touch panel according to a recognition method. touch panel).

First, the resistive touch panel is basically composed of two conductive transparent layers, the lower layer is composed of a glass or plastic coated with a conductive material, the upper layer is composed of a film coated with a conductive material. The two layers are electrically insulated at regular intervals by finely printed spacers. In the resistive touch panel, a constant voltage is applied to two layers coated with a conductive material, and when the upper plate is touched with a human hand or a touch pen, the upper (X-axis) and lower (Y-axis) surfaces are respectively changed according to the touch position. It is a device that displays coordinates or inputs data on the monitor by calculating the position of X (top) and Y (bottom) where the resistance value is changed by the controller.

Capacitive touch panels consist of a transparent glass sensor whose sensor is coated with a thin conductor coating on its surface. Thus, the electrode pattern is precisely printed along the edge over the conductive layer and a transparent glassy protective coating is adhered onto the conductor coating to protect and wrap the sensor. In the capacitive touch panel, a voltage is applied to the screen, and the electrode pattern forms a low voltage field on the touch sensor surface through the conductive layer. When the finger touches the screen, a small current flow occurs at the point of contact. The current flow from each corner is proportional to the distance from the corner to the finger, and the touch screen controller calculates the proportion of the current flow to find the position where the contact is made.

Ultrasonic touch panel is composed of 100% glass material, so even small surface damage or abrasion is not affected by surface damage or abrasion at all compared to other products that directly end the life of expensive touch screen. The touchscreen controller sends an electrical signal of 5 MHz to a transmitting transducer that generates ultrasonic waves, where the generated ultrasonic waves are passed through the panel surface by reflected lines. When the user touches the surface of the touch screen, the ultrasonic touch panel absorbs a part of the ultrasonic wave passing through the point, and the received signal and the signal lost by the digital map are immediately confirmed by the controller. Based on this, the coordinate value of the point where the current signal is changed is calculated. This series of processes is performed independently along the X and Y axes.

Infrared touch panel uses the property that the infrared ray is straight, so if there is an obstacle, it is blocked and cannot proceed. The pressure part blocks the infrared rays from the horizontal and vertical directions, and reads the X and Y coordinates of the blocked part. The infrared light method is to check the touched position by blocking the infrared scanning light rays on the front of the touch panel. The infrared touch panel forms infrared gratings by receiving infrared rays emitted from one side of each of the x and y axes and radiated infrared rays from the other side of the infrared touch panel.

Although the advantages of the above-described methods are different, in recent years, infrared touch panels have been attracting attention due to minimizing pressure applied to the touch panel and ease of arrangement.

Hereinafter, a conventional infrared touch panel will be described with reference to the accompanying drawings.

1 is a plan view illustrating a touch sensing method according to the conventional infrared touch panel.

As shown in FIG. 1, a conventional infrared touch panel includes an infrared sensor 5 at two adjacent corners of the panel 10, and a reflective plate 7 at three sides of the panel 10.

The conventional infrared touch panel uses two infrared light sources, an infrared sensor 5 and a retroreflective plate to determine coordinates by triangulation.

At this time, the method of detecting the touch is as follows. That is, the light is reflected from the infrared sensor 5 located at both ends of the panel 10, and the light is blocked when the touch is detected and calculated by an angle to recognize the touch.

However, in the case of the conventional infrared touch panel, since a dead zone area is not detected in a range over a predetermined angle between the infrared sensors 5, the touch accuracy is increased in a specific area. Decrease and adjustments are needed. In practice, for this adjustment, the infrared sensor is positioned outside the corner of the liquid crystal panel so that the dead zone region is caught outside the liquid crystal panel. In this case, a touch panel defined as a size larger than the size of the liquid crystal panel is required, which results in increasing an invalid area which does not contribute to image display, which causes a problem in that efficiency is lowered as a display device.

In general, the touch panel and the liquid crystal panel are separated, and in order to implement touch, it is necessary to combine the respective parts, apply coordinates of the touch panel to the liquid crystal panel, and fix the touch panel to the liquid crystal module.

In addition, such a conventional touch panel has a disadvantage in that it is difficult to select the correct coordinates and recognize only one contact point at a time. In other words, when two points on the touch panel are touched at the same time, the touch panel does not recognize this, or only the first touched point among the two touched points causes a touch error.

In addition, the conventional camera technology is manufactured for the use of electronic blackboard, the size of the touch module is large and heavy.

The conventional infrared touch panel as described above has the following problems.

First, in the case of applying a retroreflective panel to a rectangular display panel, a conventional infrared touch panel has a recursive reflectance that drops sharply at the point where the incident angle becomes the greatest as the incident angle of the retroreflective plate decreases as the incident angle of the retroreflective plate increases. Since the angle of incidence sensed by each side is different, the retroreflected light drops sharply in a specific area.

Second, in particular, with respect to the camera sensor located at one corner, the prism directions (vertexes) of the retroreflective plate are formed at 90 degrees to each other in two adjacent sides in the retroreflected area in the diagonal direction, and the rest of one of the adjacent two sides When it is turned to the side, the difference in incidence angle appears to be about 30 degrees, and accordingly, a peak value is generated when the amount of light is detected, resulting in poor touch performance, low touch sensitivity, and high error incidence rate when mechanical distortion or foreign matter occurs.

Third, the conventional infrared touch panel is a method of sensing the touch using two cameras, a dead zone as shown in FIG. 1 is generated in a region adjacent to the side where the camera sensors are formed, In consideration of this, the size of the touch panel should be formed with a margin larger than that of the liquid crystal panel, which causes a problem of increasing an invalid area in the display panel.

The present invention has been made to solve the above problems, and provides a method for compensating for touch sensitivity of a touch assembly integrated display device in which touch sensing is stable by compensating a light quantity difference due to a difference in incidence angle appearing for each position of the retroreflective plate. There is a purpose.

The touch sensitivity compensation method of the touch assembly integrated display device of the present invention for achieving the above object is a rectangular flat panel-shaped display panel, an infrared camera sensor provided at three or more corners of the display panel, A touch sensitivity compensation method for a touch assembly integrated display device including a retroreflective plate formed to correspond to four sides, the method comprising: sensing light amount for each region using the infrared camera sensor; and a region having a small variation in light amount The method includes increasing the sensitivity of the light amount and generating a compensated light amount by reducing the sensitivity of the light amount in a region having a large change in the light amount.

Here, the method may further include determining a threshold value for each region by using the compensated amount of light during the initial metric.

The generating of the compensated light amount corresponds to the look-up table having a log characteristic. Alternatively, it may be made to reduce the standard deviation between the amounts of light and to equalize the intensity.

The method may further include detecting whether the touch is performed and the touch coordinates by comparing the compensated amount of light with the threshold for each region.

The touch sensitivity compensation method of the touch assembly integrated display device according to the present invention has the following effects.

First, due to the difference in the arrangement of the retroreflective plate for each region, the incident angle difference of the retroreflective plate due to the difference in the prism angle in the retroreflective plate occurs. In order to compensate for the difference in the amount of light detected by the retroreflective plate for each area, the sensitivity of the light amount is increased in an area where the variation of the amount of light is large, and the sensitivity of the light amount is reduced in an area where the variation of the amount of light is small, thereby reducing the sensitivity of the display panel. Even touch sensitivity in the area can be maintained. That is, it is possible to improve the touch sensitivity at the minimum value of the light amount and to adjust the touch sensitivity at the maximum value of the light amount.

Second, based on the above-described principle, the standard reflectance of the light receiving sensor input value can be reduced by compensating the reflectance for each region of the reflecting side.

Third, in areas where the retroreflective plate is located in the diagonal region of one camera sensor, even if the retroreflective rate is rapidly reduced, the touch sensitive area may be prevented by compensating for this.

Fourth, as a light quantity compensation principle, the threshold setting for touch detection is updated according to the compensated light quantity, thereby raising the threshold value of a portion having a low threshold value by region variation of the conventional retroreflective plate, and particularly having a high threshold value. By lowering the threshold value of the site, touch detection can be performed more accurately, so that an optimal threshold level can be set.

Hereinafter, a touch sensitivity compensation method and a touch assembly display device using the same will be described in detail with reference to the accompanying drawings.

Hereinafter, the touch assembly display device will be described, and then the touch sensitivity compensation method will be described.

2 is a plan view illustrating a touch assembly integrated display device using the touch sensitivity compensation method of the present invention, and FIG. 3 is a perspective view of FIG. 2.

When the touch assembly integrated display device 1000 of the present invention is viewed in plan view, the infrared camera sensor module 200 is positioned to correspond to three or more corners of the display panel 50, and corners in which the camera sensor module 200 is installed are disposed. The guide structure 110 is provided on all four sides except for the retroreflective plate 300 including a retro-reflecting layer made of a prism formed in a plurality of rows in a row on the side of the guide structure 110. It is. The infrared camera sensor module 200, the guide structure 110, and the retroreflective plate 300 may be referred to as a touch assembly 550.

The reason for having three or more infrared camera sensor modules 200 is to prevent dead zones having weak touch sensing force adjacent to sides between sensor modules generated when two sensor modules are provided. In this case, it is possible to detect whether or not a substantial area of the touch of the dead zone in the conventional dead zone by a survey between one of the infrared camera sensor module located on the other side and the infrared camera sensor module 200 of the third corner.

The touch assembly according to the present invention includes a guide structure 110 formed of a plastic material and a retroreflective plate 300 attached to a side of the guide structure 110. Corresponding to the corner between the two sides, it comprises an infrared camera sensor module 200 formed in the space between the guide structure (110).

The guide structure 110 includes a body positioned below the case top 95, a fastening portion 115 protruding from the body, and fastened to the groove of the case top 95, and the retroreflective plate 300. A lower pedestal supporting the display panel 50 from the lower side and an upper protrusion protruding from the body to be in contact with an upper surface of the case top 95 covering the display panel 50; It is done by At this time, a double-sided adhesive (not shown) is further interposed between the retroreflective plate 300 and the protrusion of the guide structure 110 to further enhance adhesion between the two.

Here, the longest height including the protrusion, the body, the lower pedestal of the guide structure 110 is 7mm or less. In addition, the width of the guide structure 110 is 10mm or less.

In this case, the lower pedestal of the guide structure 110 is formed to protrude from the body toward the display panel 50, which is equal to or larger than the thickness of the retroreflective plate 300.

On the other hand, the guide structure 110 is formed by connecting between the sides of the infrared camera sensor module 300 is not formed. That is, referring to FIG. 2, when the infrared camera sensor module 200 is provided at three corners, the guide structure is provided for both adjacent sides of the corner at the lower right corner without the infrared camera sensor module 200. 110 is connected and formed.

In addition to the above-described touch assembly, the touch assembly integrated display device 1000 of the present invention supports the display panel 50 and the display panel 50 positioned at the lower edge thereof by the touch assembly. And a support main 400 on which the touch assembly is placed, and a backlight unit 500 disposed below the display panel 50 inside the support main.

Here, the case top 95 is formed to cover the sides of the display panel 50, the guide structure 110, the support main 400, and an upper portion of the outer portion of the protrusion 110a of the guide structure 110. do. In this case, the body of the guide structure 110 is located below the case top 95.

In this case, an upper surface bent inward to correspond to an edge of the display panel 50 of the case top 95 may be disposed on the outer upper portion of the guide structure 110 to be in contact with the protrusion 110c. In this case, the upper surface of which the upper surface of the case top 95 is bent inwardly lies on a substantially horizontal surface with the upper end of the protrusion 110c of the guide structure 110, and the metallic case top 95 is formed of the plastic. It is hidden by the guide structure 110 of the component.

Here, the fastening part 115 protruding from the guide structure 110 is fastened by the guide groove 95a provided in the case top 95.

The case top 95 is placed on the guide structure 110 attached to the side of the retroreflective plate 300, and the system cover is made of plastic to casing the case top 95 and the guide structure 110. (Not shown) are formed outside these. In this case, the upper surface of the system cover comes in to cover the retroreflective plate 300.

As described above, in the touch assembly-integrated liquid crystal display device of the present invention, a narrow bezel (ie, a touch assembly having a touch detection function) is provided by being fastened to the case top 95 without increasing the planar space of the display device. With the narrow bezel maintained, touch detection is possible.

In addition, the retroreflective efficiency may be improved by raising the height of the retroreflective plate to the upper surface of the case top 95. In this case, when the liquid crystal display of the retroreflective plate is implemented, a system cover (not shown) may be covered so as not to be exposed from the external appearance of the liquid crystal display. In this case, when viewed from the inner side of the liquid crystal display, the case top 95 is covered by the retroreflective plate 300.

The infrared camera sensor module 200 includes a protrusion 215, a guide groove (not shown) in the case top 95, and the protrusion 215 is inserted into the guide groove for ease of mounting thereof. Willing to. In addition, the infrared camera sensor module 200 is a space between the guide structures 110 formed on the different sides, which is an area corresponding to the upper portion of the edge of the display panel 50.

In this case, the case top 95 has a guide groove 95a coupled to the fastening portion 115 of the guide structure 110, and a guide coupled to the protrusion 215 of the infrared camera sensor module 200. A groove may be further provided.

In this case, the infrared camera sensor module 300 faces the corner of the display panel in the diagonal direction.

In this structure, since the case top 95, the guide structure 110, the retroreflective plate 300, the infrared camera sensor module 300 is integrated, the tempered glass for the protection of the separate display panel 50 is required. By structurally covering the case top 95 with the retroreflective plate 300 within the system cover 600, the appearance of the metallic material may be prevented from appearing and the retroreflective efficiency is also improved.

The touch assembly integrated display device of the present invention includes a display panel 50, a backlight unit 500 under the display panel 50, a side portion of the display panel 50 and the backlight unit 500, and the display. The case top 95 is fastened to the case top 95 from the inner side of the case top 95 through a case top 95 formed to cover the edge of the panel 50 and a guide groove 95a provided in the case top 95. And a guide structure 110 formed corresponding to each side of the display panel 50, a retroreflective plate 300 attached to a side of the guide structure, and two between sides and sides of the display panel 50. Including an infrared camera sensor module 200 which is located in the space between the guide structure 110, corresponding to the above corner, emits infrared rays to the touch point on the display panel 50, and senses the received light; Is done.

The touch sensing controller which controls the infrared camera sensor module 200 may be further included in a control unit that controls the display panel.

The display panel 50 may be, for example, a liquid crystal panel, and may be changed to an organic light emitting display panel, an electrophoretic display panel, a plasma display panel, or the like. In this case, the backlight unit is omitted in the case of an organic light emitting display panel or an electrophoretic display panel.

Here, the backlight unit 500 may include a light source (not shown) such as a fluorescent lamp or an LED, an optical filter (not shown) to increase the emission efficiency from the light source, and a reflector (not shown) below the light source (not shown). And a cover bottom surrounding the lower side and the side of the light source and the optical filter.

In some cases, the light source may be a direct method in which a plurality of fluorescent lamps or LEDs are arranged in parallel to the lower side of the display panel 50, or the light source may be disposed at the side and may emit light toward the display panel under the display panel. It may be made in an edge method including a light guide plate.

When the display panel 50 is, for example, a liquid crystal panel, the first and second substrates 51 and 52 which face each other and perform display through a liquid crystal therebetween, And first and second polarizing plates 53 and 54 formed on the rear surfaces of the second substrates 51 and 52, respectively.

Meanwhile, a support main 400 for supporting and seating the display panel 50 is further interposed between the lower edge of the display panel 50 and the cover bottom (a case containing the backlight unit).

In addition, the camera sensor module 200 includes a protrusion 215 at an upper portion of a portion corresponding to an edge of the display panel 50, and provides a guide groove 95a provided on an inner side surface of the case top 95. It can be formed to fit). As described above, the guide groove corresponding structure is not always necessary, but it is possible to reduce the size of the touch assembly integrated liquid crystal display and is advantageous for fixing the position of the infrared camera sensor module 200. In addition, the protrusion 215 may be formed in one or a plurality, and the shape may be changed into a polygonal shape which is easy for various fastening such as a square, an octagon or a circle.

The case top 95 may be formed in a quadrangular plane shape along the shape of the display panel 50, or may be formed in an octagonal shape having an additional diagonal line corresponding to the corner portion. In any case, the center of the display panel 50 is formed in a kind of frame shape so as to be exposed.

4A and 4B are exploded perspective and combined perspective views illustrating the infrared camera sensor of FIG. 2. These figures are perspective views showing the projections on the upper side when the actual case top 95 is mounted, and the LED lens and the photo sensor on the upper left side.

The infrared camera sensor module 200, as shown in Figs. 4a and 4b, the infrared LED 220 for emitting infrared light and the illumination system lens 235 for adjusting the outgoing angle of the light emitted from the infrared LED 220. ), An objective lens 230 that collects the received light, a photo sensor 225 that senses the light collected by the objective lens 230, and an agent positioned on the front or rear surface of the objective lens 230. One optical filter 240 is included. In addition, the infrared LED 220 is placed, the photo sensor 225 is disposed on the back side, the objective lens 230, LED lens 235 and the first optical filter 240 therein It includes a housing (210) for mounting on, and a cover mold 233 to cover the upper portion of the housing 210 to protect the internal structure.

Here, the cover mold 223 and the housing 210 have an open area so that the light passed through the cover mold 223 and the housing 210 passes through the photo sensor 225 inside the open area. Is placed. In this case, the received light is received by the photo sensor 225 via the first optical filter 24 and the objective lens 230.

In addition, the infrared LED 220 serves to emit light toward the retroreflective plate 300. Here, the illumination system lens 235 can be emitted from the infrared LED 220 at a narrow angle of up to 5 ° up and down with respect to the surface perpendicular to the lens surface of the LED 220, in the surface perpendicular to the lens surface It has an angle of view of about 90 ~ 100 °.

In addition, the photo sensor 225 may be disposed on the PCB 226 as a line sensor array including a plurality of sensors, and the PCB 226 may be connected to the display panel through a flexible printed circuit (FPC) 250. It is directly connected to the control unit. In this case, the control of the camera sensor module 200 is directly performed by the control unit of the display panel. In addition, the FPC 250 is folded at the rear side of the camera sensor module 200 and adhered to the side of the case top 95 via a double-sided tape (not shown).

In this case, the resolution of the photo sensor 225 preferably has a resolution of 500 pixels or more in the horizontal direction (to detect a position on 500 or more pixels in the horizontal direction).

In addition, the infrared LED 220 has an electrical connection with the FPC 250 where the photo sensor 225 is located and is controlled.

Meanwhile, the retroreflective plate 300 corresponds to four sides of an edge of the display panel 50 so as to be formed on the upper side thereof, and the retroreflective plate 300 is attached to the side of the guide structure 110. In this case, the infrared camera sensor module 200 formed corresponding to the upper corner of the display panel 50 and the guide structure 110 including the retroreflective plate 300 are positioned on the same plane and have a height of about 4 mm or less, It is preferably located on the same plane as the guide structure 110 of a height of 3.5 mm or less.

Referring to FIG. 4B (the portion in which the direction corresponding to c in the drawing is directed toward the liquid crystal panel), both the depth a and the length b are 10 mm or less, and the height c is 3.5 mm or less. Located in the space between the liquid crystal panel 50 and the case top 95.

The infrared camera sensor module 200 receives the light that is retroreflected from at least two surfaces, respectively, and serves to sense the light emitted from the other camera sensor module 200 at the corner portion of the diagonal front.

In addition, the infrared camera sensor module 200 may emit light or recursion emitted from the infrared camera at the touch point of the reflected light or the touch object (input means such as a hand or a pen) reflected from the retroreflective plate 300 when the touch is performed. Sensing that the reflected light is blocked.

5 is a cross-sectional view illustrating the retroreflective plate of FIG. 2.

As illustrated in FIG. 5, in the touch assembly integrated display device, the retroreflective plate 300 may include a retro-reflector layer 312 and first and second surfaces formed on the bottom and top surfaces of the retroreflective layer 312, respectively. An adhesive layer 310, a second adhesive layer 313, and a second optical filter 314 on the second adhesive layer 312.

Here, the retroreflective plate 300 is attached to the side (upper protrusion 110c) of the guide structure 110 through its first adhesive layer 310, adjacent to the camera sensor module 200 of the corner portion. Is formed.

In addition, the retroreflective layer 312 is formed of a cube-shaped cube having a good wide angle at an angle of incidence of 0 ° to 65 °, and has a shape in which a kind of micro prism is continuously formed. Can be made.

The second optical filter 314 is an optical filter having a property of transmitting only infrared light having a wavelength of about 700 nm or more. At this time, the optical filter may be made of an acrylic resin. For example, polymethyl methacrylate (PMMA) or polycarbonate may be used.

In addition, in order to transmit only infrared rays, the color may be formed by black resin or the like so as to have visible light absorption characteristics.

Alternatively, the optical filter may include a glass component.

Here, the retroreflective plate 300 receives and emits light emitted from the infrared camera sensor module 200 and reflects it again.

On the other hand, in the touch assembly integrated liquid crystal display of the present invention, the camera sensor module 200 is disposed at three or more corners, in one-point touch, by using two adjacent sensors, at the touch point in the retroreflective plate 300. In order to detect that the light emitted from the infrared camera is blocked at the touch point of the reflected reflected light or the touch object (an input means such as a hand or a pen), and in the case of multi-touch above this advantage, two primarily adjacent infrared cameras In order to recognize the multi-touch by applying a virtual image elimination algorithm by sensing the point error generated during the touch point sensing using the remaining infrared camera and the adjacent infrared camera.

6 is a diagram illustrating reflection efficiency according to an incident angle of a retroreflective plate.

In the retroreflective plate, incident light enters a side corresponding to the hypotenuse of the prism mountain of the retroreflective wave layer 312 based on FIG. 5, and when the incident angle enters the direction perpendicular to the hypotenuse, the incident angle is 0 degrees and the vertical direction. The angle of incidence gradually increases as it has a slope in one direction.

As for the relationship between the incident angle and the retroreflective efficiency of such a retroreflective plate, as shown in FIG. 6, as the incident angle increases, the retroreflective efficiency gradually increases. The retroreflective efficiency of the retroreflective plate may vary from product to product, but the retroreflective efficiency changes to near zero, which is generally over 70 degrees of incidence angle, and thus, it is difficult to function as a retroreflective plate when the incidence angle is large.

The retroreflective plate used in the touch sensitivity compensation method of the touch assembly integrated display device of the present invention selects a material exhibiting good reflection efficiency at an incident angle between about 0 degrees and 65 degrees.

FIG. 7 is a graph illustrating retroreflectivity according to a measurement angle when a retroreflective plate is applied to a touch assembly integrated display device according to an exemplary embodiment of the present invention. FIG. 8 is a graph illustrating measurement angles at each corner when the retroreflective plate is positioned at four sides of a display panel. It is a diagram showing the difference in incident angles detected by the retroreflective plate.

Meanwhile, as shown in FIG. 8, in the retroreflective layer 312 provided with the prism mountain of the retroreflective plate, hypotenuses of the prisms correspond to the edge of the display panel. At this time, at the point ③, the measurement angle is switched from the lower side to the right side, and the directions of the prism peaks of the retroreflective layers on the adjacent sides are bent at 90 degrees to each other. This is a sharp bending phenomenon from 60 to 29 degrees.

As shown in FIG. 7, the retroreflectivity according to the standardized measurement angle (the angle represented by converting the resolution to the measurement angle for one infrared camera sensor) is 70% at the measurement angle of about 30% at the measurement angle of 61 degrees. A sharply rising area is observed. This is the position where the direction of the prism mountain of the retroreflective plate shown in FIG. 8 is bent.

Such rapid change in the retroreflectivity is caused by the specificity of the arrangement of the retroreflective plate, and in view of this characteristic, a method of compensating the touch sensitivity is introduced.

9 is a flowchart illustrating a touch sensitivity compensation method of the present invention.

The touch sensitivity compensation method of the touch assembly integrated display device of the present invention uses the touch assembly integrated display device described with reference to FIGS. 2 to 5.

As shown in FIG. 9, first, a lookup for generating a compensated amount of light by increasing the sensitivity of the light amount in a region having a small degree of change in light quantity according to the amount of light, and decreasing the sensitivity of the light amount in a region having a large degree of change in light quantity Create a table (S10).

In this case, the lookup table may use, for example, an example in which a function showing a log characteristic with respect to the amount of light is applied, or an example in which a function value having a characteristic similar to that of a log corresponds. This is to reduce the standard deviation between the amounts of light and to make the intensity even. Here, the lookup table receives the light amount through an analog digital converter (ADC) and outputs data corresponding to the compensated light amount having a log characteristic.

The method may further include detecting whether the touch is performed and the touch coordinates by comparing the compensated amount of light with the threshold for each region.

Next, the amount of light per area is sensed using the infrared camera sensor (S20).

Subsequently, the amount of light sensed for each region is corrected using the lookup table to generate data using the compensated light amount (S30).

Here, a threshold value is determined using the said data (compensated light quantity) at the time of a metric value (S40). For example, a value corresponding to 0.8 times or 0.9 times the amount of compensated light may be defined as a threshold.

In this case, when the threshold value is equal to or less than the threshold value and the amount of light (data) compensated for the subsequent touch, the touch point is detected and the corresponding position is detected by the touch coordinates.

FIG. 10 is a graph illustrating a lookup table used when compensating for the light quantity of FIG. 9. FIG.

FIG. 10 illustrates a look-up table used to compensate for the above-described light quantity. When the input value output through the ADC corresponds to about 0 to 255, the output value shows a large change when the input value is small. When it is larger than a certain level, it shows the output value which changes with little change | approximately, and it shows that it has an approximate log characteristic.

11 is a graph showing values before and after light compensation using a lookup table and corresponding threshold values.

As shown in FIG. 11, before light compensation, at about 150 pixels to 320 pixels, the output value output from the infrared camera sensor module was considerably low, and thus the threshold value was also set low in this area, so that touch in this area was It can be seen that it is difficult to detect whether or not there is a touch. This is detected when there is a touch because the amount of sensing light of the infrared camera sensor is low because the reflected light from the retroreflective plate and the direct light from the light source of the infrared camera sensor are blocked by touching the corresponding area. If the value is very low, it is difficult to identify whether the amount of light sensed due to the actual touch is low and whether the retroreflected light from the retroreflective plate is low by its incident angle characteristic.

However, when the light amount compensation is performed, the light amount at the time of metering is compensated for and increased in the region where the light amount is low (about 150 pixels to 320 pixels), and the corresponding threshold value can be improved accordingly. You may become sensitive.

This light amount compensation process is similarly applied from about 330 pixels to 500 pixels.

In addition, from about 320 pixels to 330 pixels, the amount of light sensed from the infrared camera sensor module before the light compensation is increased due to the other camera sensor module. It was. As described above, since the amount of light sensed by the compensation process is applied by applying the lookup table and thus the threshold value is lowered, the accuracy of whether or not the touch is improved can be improved.

On the other hand, the present invention described above is not limited to the above-described embodiment and the accompanying drawings, it is possible that various substitutions, modifications and changes within the scope without departing from the technical spirit of the present invention. It will be apparent to those of ordinary skill in Esau.

1 is a plan view showing a touch sensing method according to the conventional infrared touch panel

2 is a plan view illustrating a touch assembly integrated display device using the touch sensitivity compensation method of the present invention.

3 is a perspective view of FIG. 2

4A and 4B are exploded perspective and combined perspective views illustrating the infrared camera sensor of FIG. 2;

5 is a cross-sectional view illustrating the retroreflective plate of FIG. 2.

6 is a graph illustrating reflection efficiency according to an incident angle of a retroreflective plate;

7 is a graph illustrating retroreflectivity according to a measurement angle when a retroreflective plate is applied to a touch assembly integrated display device according to an exemplary embodiment of the present invention.

FIG. 8 is a diagram illustrating a difference between a measurement angle at each corner and an incident angle detected by the retroreflective plate when the retroreflective plate is positioned at four sides of the display panel. FIG.

9 is a flow chart showing a touch sensitivity compensation method of the present invention

FIG. 10 is a graph illustrating a lookup table used when compensating for light quantity of FIG. 9. FIG.

11 is a graph showing values before and after light compensation using a lookup table and respective corresponding threshold values.

* Description of the symbols for the main parts of the drawings *

50: display panel 95: case top

110: guide structure 200: infrared camera sensor module

210: housing 215: protrusion

220: infrared LED 225: photo sensor

226: sensor PCB 230: objective lens

233: cover mold 235: LED lens (light system lens)

240: first optical filter 250: FPC

255: double-sided tape 300: retroreflective plate

310: first adhesive layer 312: retroreflective layer

313: second adhesive layer 314: second optical filter

400: support main 500: backlight unit

Claims (5)

And a rectangular flat panel display panel, an infrared camera sensor provided at three or more corners of the display panel, and a retroreflective plate formed to correspond to four sides of the display panel. In Sensing light amount for each region using the infrared camera sensor; And increasing the sensitivity of the light amount in the region where the change in the amount of light is small, and generating a compensated light amount by reducing the sensitivity of the light amount in the region where the change in the amount of light is large. Method of compensating touch sensitivity of an integrated display device. The method of claim 1, And determining a threshold value for each region by using the compensated light amount at the time of initial metric measurement. The method of claim 1, The generating of the compensated light amount may correspond to the light amount corresponding to a look-up table having a log characteristic. The method of claim 1, The generating of the compensated light amount may include reducing the standard deviation between the light amounts and equalizing the intensity of the light amount. 3. The method of claim 2, And detecting touch and touch coordinates by comparing the compensated amount of light with a threshold value for each region.

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