WO2016132732A1

WO2016132732A1 - Display panel

Info

Publication number: WO2016132732A1
Application number: PCT/JP2016/000780
Authority: WO
Inventors: 高士山田; 山口　博史
Original assignee: パナソニックＩｐマネジメント株式会社
Priority date: 2015-02-18
Filing date: 2016-02-16
Publication date: 2016-08-25

Abstract

A display panel that, together with an optical device equipped with an emission unit for emitting invisible light and a reception unit for receiving reflected invisible light, forms a display control system. A transparent medium (413) having a refractive index n connects an invisible light reflection layer (432) and a pattern layer of the display panel. For the dots (411) forming the pattern layer, the distance X from the tip end on the side facing the invisible light reflection layer (432) to the average line of the surface shape of the invisible light reflection layer (432) satisfies the equation W/2 ≤ X < D/tan[sin^-1{sin θ/n}], where D is the average major diameter of the dots (411) forming the pattern layer, W is the average height difference of the surface shape of the invisible light reflection layer (432), and θ (0 < θ < π/2(90°)) is the angle formed by the light axis of the emission unit and the light axis of the reception unit of the optical device.

Description

Display panel

This disclosure relates to a display panel that forms a display control system together with an optical device that emits invisible light and receives reflected invisible light.

A technique for reading a position information pattern representing a coordinate position on a plane of a display device using a pen-type reading device is known. The reading device receives the invisible light reflected by the display device after emitting the invisible light, and specifies the coordinate position indicated on the display device based on the received invisible light. For example, the Example using an optical film like patent document 1 is known.

JP 2008-209598 A

This disclosure provides a display panel that can obtain higher reading performance of position coordinates while reducing restrictions on material selection and manufacturing method.

The display panel according to the present disclosure is a display panel that forms a display control system together with an optical device that includes an emitting unit that emits invisible light and a light receiving unit that receives reflected invisible light. The display panel includes a pattern layer and a non-visible light reflection layer. The pattern layer is formed with a pattern of dots in accordance with a predetermined rule in order for the optical device to specify the position information pointed to by the optical device on the display panel. The non-visible light reflection layer is disposed to face the pattern layer, and reflects at least a part of the non-visible light emitted from the optical device to the optical device through the pattern layer. The pattern layer and the invisible light reflection layer are connected by a transparent medium having a refractive index n. The distance X from the tip of each dot forming the pattern layer on the side facing the non-visible light reflecting layer to the average line of the surface shape of the non-visible light reflecting layer is W / 2 ≦ X <D / tan [sin ^{− 1} {sin θ / n}]. Here, the average major axis of each dot forming the pattern layer is D, the average height difference of the surface shape of the non-visible light reflecting layer is W, and the angle formed by the optical axis of the emitting part of the optical device and the optical axis of the light receiving part Is θ (0 <θ <π / 2).

More preferably, the expression of W / 2 ≦ X <D / (2 × tan [sin ⁻¹ {sin θ / n}]) is satisfied. More preferably, the formula of X = W / 2 is satisfied.

The display panel according to the present disclosure is a display panel that can use an optical device that emits invisible light and receives reflected invisible light. The display panel includes a pattern layer, a non-visible light reflection layer, and a transparent medium having a refractive index n. The pattern layer is formed with a dot pattern. The non-visible light reflection layer is disposed to face the pattern layer, and reflects at least a part of the non-visible light emitted from the optical device to the optical device through the pattern layer. A transparent medium having a refractive index n is provided between the pattern layer and the non-visible light reflection layer. The distance X from the surface of each dot forming the pattern layer facing the non-visible light reflecting layer to the average line of the surface shape of the non-visible light reflecting layer is W / 2 ≦ X <D / tan (sin ⁻¹ [ {Sin (π / 4)} / n]) is satisfied. Here, the average major axis of each dot forming the pattern layer is D, and the average height difference of the surface shape of the invisible light reflecting layer is W.

More preferably, the following formula is satisfied: W / 2 ≦ X <D / {2 × tan (sin ⁻¹ [{sin (π / 4)} / n])}. More preferably, the formula of X = W / 2 is satisfied.

FIG. 1 is an image diagram showing an appearance of the display control system 100. FIG. 2 is a block diagram illustrating a configuration of the display control system 100. FIG. 3 is a cross-sectional view of the display panel 210 according to the first embodiment. FIG. 4 is an enlarged view of a part of the display panel 210 according to the first embodiment in order to explain details of the positional relationship between the dot pattern sheet 410 and the infrared reflective sheet 430. FIG. 5 is a diagram illustrating the interval between the dot 411 and the dot shadow. FIG. 6 is a first diagram for explaining the optimum range of the distance X. In FIG. FIG. 7 is a second diagram for explaining the optimum range of the distance X. In FIG. FIG. 8A is an enlarged image diagram for explaining a dot pattern. FIG. 8B is an enlarged image diagram for explaining the dot pattern. FIG. 9A is a schematic diagram for explaining that information obtained by digitizing the position of the dot 411 differs depending on the position of the dot 411. FIG. 9B is a schematic diagram for explaining that information obtained by digitizing the position of the dot 411 differs depending on the position of the dot 411. FIG. 9C is a schematic diagram for explaining that information obtained by digitizing the position of the dot 411 differs depending on the position of the dot 411. FIG. 9D is a schematic diagram for explaining that information obtained by digitizing the position of the dot 411 differs depending on the position of the dot 411. FIG. 10 is a flowchart showing the operation of the display control system 100.

Hereinafter, embodiments will be described in detail with reference to the drawings as appropriate. However, more detailed description than necessary may be omitted. For example, detailed descriptions of already well-known matters and repeated descriptions for substantially the same configuration may be omitted. This is to avoid the following description from becoming unnecessarily redundant and to facilitate understanding by those skilled in the art.

In addition, the inventor provides the accompanying drawings and the following description in order for those skilled in the art to fully understand the present disclosure, and is not intended to limit the claimed subject matter. .

(First embodiment)
FIG. 1 is an image diagram showing an appearance of a display control system 100 according to the first embodiment. The display control system 100 includes a display device 200 and an optical digital pen (hereinafter simply referred to as “digital pen”) 300. The display device 200 includes a display panel 210. On the surface of the display panel 210, a display surface capable of displaying an image or the like is defined.

On the display surface of the display panel 210, a dot pattern representing information on the position on the display panel 210 is provided. The digital pen 300 optically reads the dot pattern at the pen tip position, thereby detecting information on the position on the display panel 210 where the tip of the digital pen 300 is located (hereinafter also referred to as “position information”). be able to. The display device 200 and the digital pen 300 are in wireless communication, and the digital pen 300 transmits the detected position information to the display device 200. Thereby, the display apparatus 200 can grasp position information indicating the pen tip position of the digital pen 300 and performs various display controls.

For example, it is assumed that the tip of the digital pen 300 is moved on the display panel 210. At this time, the digital pen 300 detects continuous position information as a locus of the tip of the digital pen 300 from the dot pattern continuously read. The digital pen 300 sequentially transmits the detected position information to the display device 200. Thereby, the display device 200 can continuously display dots on the display panel 210 according to the locus of the tip of the digital pen 300. Using this function, the user can input characters, figures, and the like on the display panel 210 by handwriting with the digital pen 300.

[2. Configuration of Display Control System 100]
Next, the configuration of the display control system 100 will be described. FIG. 2 is a block diagram illustrating a configuration of the display control system 100.

The display device 200 includes a display panel 210, a receiving unit 230, a display-side microcomputer 240, and a display device-side memory 250. The display device 200 may have other electrical configurations, but the description is omitted.

The display panel 210 can display an image in accordance with control from the display-side microcomputer 240. The display panel 210 can be realized by, for example, a liquid crystal display method or an organic EL method. Details of the layer structure of the display panel 210 will be described later.

The receiving unit 230 receives a signal transmitted from the digital pen 300. The receiving unit 230 transmits the received signal to the display side microcomputer 240.

The display-side microcomputer 240 includes a CPU and a memory. The display-side microcomputer 240 controls the content displayed on the display panel 210 based on the signal transmitted from the digital pen 300.

The display device side memory 250 stores a program for operating the CPU of the display side microcomputer 240. The display-side microcomputer 240 can read and write information from the display device-side memory 250 as appropriate.

Next, a detailed configuration of the digital pen 300 will be described with reference to FIG.

The digital pen 300 includes a cylindrical main body case 310 and a pen tip portion 320 attached to the tip of the main body case 310. The digital pen 300 includes a pressure sensor 330, an objective lens 340, an image sensor 350, a pen side microcomputer 360, a pen side memory 390, a transmission unit 370, and an illumination unit 380 inside the main body case 310.

The main body case 310 has the same external shape as a general pen and is formed in a cylindrical shape. The pen tip portion 320 is formed in a tapered shape. The tip of the pen tip 320 is rounded to the extent that the surface of the display panel 210 is not damaged. Note that the shape of the pen tip portion 320 is preferably a shape that allows the user to easily recognize an image displayed on the display panel 210.

The pressure sensor 330 is built in the main body case 310 and connected to the proximal end portion of the pen tip portion 320. The pressure sensor 330 detects the pressure applied to the pen tip portion 320 and transmits the detection result to the pen-side microcomputer 360. Specifically, the pressure sensor 330 detects the pressure applied from the display panel 210 to the pen tip portion 320 when the user enters characters or the like on the display panel 210 using the digital pen 300. The pressure sensor 330 is used, for example, when determining whether or not the user intends to input using the digital pen 300.

The illumination unit 380 is provided at the tip of the main body case 310 and in the vicinity of the pen tip unit 320. The illumination part 380 is comprised by infrared LED, for example. The illumination unit 380 is provided to irradiate infrared light from the tip of the main body case 310 when the user's input intention is determined based on the detection result of the pressure sensor 330.

The objective lens 340 causes the image sensor 350 to form an image of light incident from the pen tip side. The objective lens 340 is provided at the distal end portion of the main body case 310 and in the vicinity of the pen tip portion 320. When infrared light is irradiated from the illumination unit 380 with the tip of the digital pen 300 facing the display surface of the display device 200, the infrared light is incident on the display panel 210 and diffusely reflected in the display panel 210. As a result, part of the infrared light transmitted through the display panel 210 returns to the digital pen 300 side. Infrared light emitted from the illumination unit 380 and diffusely reflected by the display device 200 is incident on the objective lens 340. The image sensor 350 is provided on the optical axis of the objective lens 340. Therefore, the infrared light that has passed through the objective lens 340 is imaged on the imaging surface of the image sensor 350.

The image sensor 350 outputs an image signal obtained by converting an optical image formed on the imaging surface into an electric signal to the pen-side microcomputer 360. The image sensor 350 is configured by, for example, a CCD image sensor or a CMOS image sensor. As will be described in detail later, the display panel 210 has a dot pattern formed of dots 411. The dots 411 are formed of a material that absorbs infrared light (a material with low transmittance with respect to infrared light). Therefore, the infrared light hardly returns to the digital pen 300 from the dots 411 constituting the dot pattern. On the other hand, more infrared light returns from the area between the dots 411 than from the area of the dots 411. As a result, an optical image in which the dot pattern is expressed in black is captured by the image sensor 350.

The pen-side microcomputer 360 specifies position information on the display panel 210 of the digital pen 300 based on the image signal generated by imaging by the image sensor 350. Specifically, the pen-side microcomputer 360 acquires the pattern shape of the dot pattern from the image signal generated by imaging by the image sensor 350, and specifies the position of the pen tip 320 on the display panel 210 based on the pattern shape. .

The pen side memory 390 stores a program for operating the CPU of the pen side microcomputer 360. The pen side microcomputer 360 can read and write information from the pen side memory 390 as appropriate.

The transmission unit 370 transmits a signal to the outside. Specifically, the transmission unit 370 transmits the position information specified by the pen-side microcomputer 360 to the reception unit 230 of the display device 200 that is a wireless communication partner.

[3. Details of Configuration of Display Panel 210]
Next, details of the configuration of the display panel 210 will be described. FIG. 3 is a cross-sectional view of the display panel 210 according to the first embodiment.

As shown in FIG. 3, the display panel 210 includes an optical film 400, a transparent adhesive layer 431, a touch sensor glass 440, a liquid crystal panel 450, and a backlight device 460.

The optical film 400 is configured by laminating a dot pattern sheet 410 and an infrared reflection sheet 430 via a transparent medium layer 413. The dot pattern sheet 410 has a dot pattern composed of a PET film 412 as a base material and a plurality of dots 411.

The PET film 412 protects the surface of the display panel 210 and also functions as a base material for laminating layers such as the dots 411.

A plurality of dots 411 are laminated on the back surface of PET film 412 (the lower surface in FIG. 3). Each dot 411 protrudes from the back surface of the PET film 412 by its own thickness. One dot pattern is formed by a set of a plurality of dots 411 in the unit area 213, which will be described in detail later. The dots 411 are formed of a material that absorbs infrared light (a material with low transmittance with respect to infrared light).

The infrared reflection sheet 430 includes an uneven base 433 and an infrared reflection layer 432 formed along the uneven surface 434 of the uneven base 433. The concavo-convex base material 433 has a concavo-convex surface 434 having a fine concavo-convex shape in which an inclination at a predetermined angle with respect to a reference surface (concave / convex surface average line 435) is defined in order to improve infrared reflection performance.

As an example, in the infrared reflective sheet 430 (uneven base material 433), the distribution rate f (α = 25 °) when the absolute inclination angle α of the uneven surface 434 is 25 ° is 0.5 (% / °) or more. In addition, in the effective total area of the infrared reflective sheet 430, the ratio of the projected area occupied by the region where the absolute inclination angle α of the uneven surface 434 is 40 ° or more is 20% or less. Here, an absolute angle (<90 °) at which each uneven shape of the uneven surface 434 is inclined with respect to the reference surface 435 is an absolute inclination angle α, and the distribution rate f (α) is expressed by the following formula 1. The unit of α is [°].

Sa represents the effective total area of the infrared reflection sheet 430. The effective total area is the total projected area of a region (effective surface) where the uneven shape of the uneven surface 434 is formed substantially uniformly. dα represents a minute angle near the absolute inclination angle α. ds indicates a projected area occupied by a region where the absolute inclination angle of the uneven surface 434 is in the range of α to α + dα in the effective plane. The projected area is not the area of the curved surface along the concavo-convex shape of the concavo-convex surface 434 but the area of the plane projected on the flat surface (reference surface) obtained by averaging the concavo-convex surface 434.

By so doing, infrared diffuse reflection characteristics can be imparted to the infrared reflection sheet 430. The infrared light emitted from the illumination unit 380 built in the digital pen 300 is diffusely reflected by the infrared reflection sheet 430, and the infrared reflected light is incident on the image sensor 350 built in the digital pen 300. it can. In addition, said uneven | corrugated shape is an example and you may form uneven | corrugated shape by other conditions.

The infrared reflective layer 432 is a layer that reflects infrared light while transmitting visible light. When viewed microscopically, the infrared reflection layer 432 specularly reflects infrared rays. On the other hand, when viewed macroscopically, the infrared reflection sheet 430 functions as an infrared diffuse reflection member that diffuses and reflects infrared rays because the infrared reflection layer 432 is formed along the uneven surface 434.

The transparent medium layer 413 is a layer for bonding the dot pattern sheet 410 and the infrared reflective sheet 430. Further, the transparent medium layer 413 is laminated between the dot pattern sheet 410 and the infrared reflection sheet 430 so as to fill a space between the plurality of dots 411. The transparent medium layer 413 is formed of a material that transmits both visible light and infrared light. The transparent medium layer 413 has a refractive index (refractive index n) substantially equal to the refractive index of the material of the PET film 412, the dots 411, and the uneven substrate 433. The surface of the infrared reflective sheet 430 on the dot pattern sheet 410 side has an uneven shape due to the uneven surface 434. Therefore, when the dot pattern sheet 410 and the infrared reflection sheet 430 are bonded to each other, the transparent medium layer 413 fills the gap by flattening the concavo-convex shape and functions to optically couple.

The touch sensor glass 440 is a glass including a sensor that detects contact of a finger by a user's touch operation with respect to the display panel 210 by a known technique. The touch sensor glass 440 is disposed on the back surface (the bottom surface in FIG. 3) of the infrared reflective sheet 430. The surface of the touch sensor glass 440 and the back surface of the infrared reflective sheet 430 are bonded by a transparent adhesive layer 431.

The liquid crystal panel 450 is a device that displays an image based on visible light irradiation using the backlight device 460 as a light source by controlling the orientation of liquid crystal molecules. The liquid crystal panel 450 includes a color filter layer 451 including a black matrix 453, a liquid crystal layer, and the like. The black matrix 453 forms, for example, a lattice structure (pixel structure) that partitions the RGB color filters 452. On the back surface of the liquid crystal panel 450, a backlight device 460 for irradiating the liquid crystal panel 450 with light is disposed. The liquid crystal panel 450 applies a voltage for changing the liquid crystal alignment of the liquid crystal layer based on display control by the display-side microcomputer 240. Accordingly, the liquid crystal panel 450 controls the amount of light transmitted from the backlight device 460 and executes various display operations. The liquid crystal panel 450 is disposed on the back surface of the touch sensor glass 440 (the lower surface in FIG. 3).

Subsequently, details of the positional relationship between the dot pattern sheet 410 and the infrared reflection sheet 430 will be described. FIG. 4 is an enlarged view of a part of the display panel 210 in order to explain the details of the positional relationship between the dot pattern sheet 410 and the infrared reflection sheet 430.

When the dot 411 is directly formed on the infrared reflecting sheet 430, it is necessary to consider the adhesiveness between the materials, the surface wettability, the difference in processing temperature depending on each material, etc. There were method limitations. Therefore, in the display panel 210 according to the first embodiment, the dot pattern sheet 410 and the infrared reflection sheet 430 are individually manufactured and bonded to each other with a transparent medium layer 413. Thereby, the display panel 210 with few restrictions of a manufacturing method can be provided in material selection. For the transparent medium layer 413, for example, a photocurable transparent adhesive or a transparent adhesive is used.

Here, the distance from the tip of each dot 411 forming the dot pattern sheet 410 on the side facing the infrared reflection sheet 430 (infrared reflection layer 432) to the average line of the uneven surface 434 of the infrared reflection sheet 430 is determined. Let X be. When this distance X is large, the shadow of the dot 411 illuminated by the infrared light from the illumination unit 380 of the digital pen 300 is projected onto the surface portion of the infrared reflection sheet 430. This becomes a double image that overlaps the original image of the dot 411, and a reading error may occur in the digital pen 300.

Here, the average height difference of the uneven surface 434 of the infrared reflection sheet 430 (infrared reflection layer 432) is defined as W. At this time, at the distance X = W / 2 where the dot 411 is closest to the uneven surface 434, the double image is not generated, which is the most desirable condition. However, it has been found that even if the distance X is not set to W / 2, the influence of the dots 411 can be reduced and the occurrence of a reading error can be prevented if the distance X is set to an appropriate range. Hereinafter, an appropriate range of the distance X for preventing occurrence of a reading error will be described.

Here, an inclination angle of the digital pen 300 with respect to the display panel 210 (an angle formed by the illumination unit 380 optical axis and the image sensor 350 optical axis) is θ (0 <θ <π / 2 (90 °)). An appropriate range of the distance X can be calculated from the major axis size D of the dots 411, the angle θ, and the refractive index n of the transparent medium layer 413.

FIG. 5 is a diagram illustrating the interval between the dot 411 and the dot shadow. As shown in FIG. 5, when the infrared light from the illumination unit 380 of the digital pen 300 is illuminated from directly above the dot 411, a shadow as indicated by a broken line is generated immediately below the dot 411. In the shadow portion, there is no diffuse reflection of the illumination light, and diffuse reflection light is radiated from other areas, so that the shadow is observed at a position away from the original dot 411 from the image sensor 350 in the inclination θ direction. . Let L be the distance between the dot 411 and the dot shadow. At this time, the interval L is expressed by Equation 2 where φ is the converted angle in the transparent medium layer 413 of the angle θ. The units of θ and φ are [rad].

Also, when the refractive index of the air layer is 1.0, Equation 3 is established according to Snell's law.

Therefore, the following equation 4 is established for the conversion angle φ.

Substituting equation 4 into equation 2 results in equation 5.

The digital pen 300 is a small device that requires portability and operability in consideration of usage. Therefore, the digital pen 300 is not expected to be thick, and the angle θ formed by the illumination unit 380 optical axis provided in the digital pen 300 and the image sensor 350 optical axis is not a large angle. In reality, the angle θ is considered to be π / 4 (45 °) or less. Preferably, considering the portability and operability of the digital pen 300, the angle θ is preferably π / 9 (20 °) or less. Since the double image is more likely to appear as the angle θ is larger, an example will be described in which the worst case is calculated and θ = π / 4. Here, it is assumed that the major axis of the digital pen 300 and the optical axis of the image sensor 350 are the same.

FIG. 6 is a first diagram for explaining the optimum range of the distance X. As shown in FIG. 6, when the infrared light from the illumination unit 380 of the digital pen 300 is illuminated from directly above the dots 411, the pen angle θ is π with respect to the normal line of the dot pattern sheet 410 (display panel 210). / 4. When the interval L in Formula 5 becomes equal to the dot diameter D, the image of the dot 411 and the shadow image of the dot 411 are separated into one image and captured by the image sensor 350. When the interval L is equal to the dot diameter D in Equation 5, assuming that θ = π / 4, the following Equation 6 is derived.

At this time, since an image that should originally be captured as one dot 411 is captured as two dot images, a reading error of the dot 411 occurs.

FIG. 7 is a second diagram for explaining the optimum range of the distance X. As shown in FIG. 7, when the interval L is half D / 2 of the dot diameter D, the image of the dot 411 and the shadow image of the dot 411 are displayed on the image sensor 350 as a double image in which about half are overlapped. Imaged. When the condition is solved with respect to the distance X in the same manner as the derivation of Equation 6, the following Equation 7 is derived.

In this case, since the originally sized dots 411 are picked up as a large and thick image as a double image, the occurrence of reading errors such as the two dot images described with reference to FIG. 6 is reduced. However, when the writing speed of the digital pen 300 is increased, there is a concern that adjacent dots 411 are connected and imaged, and a reading error occurs.

From the above examination, the range shown in the following equation 8 is suitable for setting the distance X.

More preferably, the distance X is set in the range shown in the following equation (9).

As described above, if the range of the distance X is appropriately set, it is possible to construct a system that is excellent in reading performance by the digital pen 300 and is easy to manufacture. In order to set the distance X, a sheet-like adhesive film set to a predetermined thickness may be used. Thereby, the sheet | seat in which the range of the distance X was set appropriately can be manufactured simply.

Here, the real value as an example is that the diameter D of the dot 411 is about 80 to 200 μm, the refractive index n of the transparent medium layer 413 is about 1.4 to 1.6, and the average height difference of the uneven surface 434 is W. Is 1 to 10 μm. For example, the angle θ between the illumination unit 380 optical axis and the optical axis of the image sensor 350 = π / 4, the dot major axis size D = 120 μm, the refractive index n = 1.5 of the transparent medium layer, and W = 5 μm. At this time, an appropriate range of the distance X is a range shown in Formula 10, more preferably in Formula 11.

[4. Details of dot pattern]
Details of the dot pattern will be described below. 8A and 8B are enlarged views when the optical film 400 is viewed from the front. 8A and 8B, in order to explain the position of the dot 411 of the dot pattern, the first reference line 414 is assumed as a virtual line (a line that does not actually exist on the optical film 400) on the optical film 400. And a second reference line 415. The first reference line 414 and the second reference line 415 are orthogonal to each other. 8A and 8B, a plurality of first reference lines 414 and a plurality of second reference lines 415 form a lattice.

Each dot 411 is arranged around the intersection of the first reference line 414 and the second reference line 415. That is, each dot 411 is arranged in the vicinity of each lattice point. 9A to 9D are diagrams showing arrangement patterns of the dots 411. FIG. Each dot 411 has an X direction from the intersection of the first reference line 414 and the second reference line 415 when the extending direction of the first reference line 414 is the X direction and the extending direction of the second reference line 415 is the Y direction. It is disposed at a position offset (shifted) to the plus side or the minus side along the direction or the Y direction. Specifically, in the optical film 400, the dots 411 are arranged in any one of FIGS. 9A to 9D. In the arrangement of FIG. 9A, the dot 411 is arranged at a position above the intersection of the first reference line 414 and the second reference line 415. When this arrangement is digitized, it is represented by “1”. In the arrangement of FIG. 9B, the dot 411 is arranged at a position on the right side of the intersection of the first reference line 414 and the second reference line 415. When this arrangement is digitized, it is represented by “2”. In the arrangement of FIG. 9C, the dot 411 is arranged at a position below the intersection of the first reference line 414 and the second reference line 415. When this arrangement is digitized, it is represented by “3”. In the arrangement of FIG. 9D, the dot 411 is arranged at a position on the left side of the intersection of the first reference line 414 and the second reference line 415. When this arrangement is digitized, it is represented by “4”. As described above, each dot 411 is represented by a numerical value from “1” to “4” in the digital pen 300 according to the arrangement pattern.

8B, 6 dots × 6 dots are defined as one unit area 213, and one dot pattern is formed by 36 dots 411 included in the unit area 213. By arranging each of the 36 dots 411 included in the unit area 213 in any one of “1” to “4” shown in FIGS. 9A to 9D, a huge number (6 dots × In the case where 6 dots are used as one unit area, a dot pattern of 4 to the 36th power can be formed.

[5. Display Operation of Display Control System 100]
Subsequently, a display operation of the display control system 100 configured as described above will be described. FIG. 10 is a flowchart showing the flow of the display operation. In the following, a case where the user performs a pen input (entry) on the display device 200 using the digital pen 300 will be described.

First, the display device 200 and the digital pen 300 constituting the display control system 100 are turned on. As a result, the display-side microcomputer 240 is supplied with power from a power source (not shown) and completes initial operations for executing various operations. Similarly, the pen-side microcomputer 360 is supplied with power from a power supply (not shown), and completes initial operations for executing various operations. The display device 200 and the digital pen 300 establish wireless communication with each other. As a result, communication from the transmission unit 370 of the digital pen 300 to the reception unit 230 of the display device 200 is enabled.

Subsequently, the pen-side microcomputer 360 of the digital pen 300 starts monitoring the pressure acting on the pen tip 320 (S500). This pressure is detected by the pressure sensor 330. When the pressure is detected by the pressure sensor 330 (Yes in S500), the pen-side microcomputer 360 determines that the user is pen-inputting characters or the like to the display panel 210 of the display device 200, and the illumination unit 380 Infrared light irradiation is started. While the pressure is not detected by the pressure sensor 330 (while No in S500 continues), the pen-side microcomputer 360 repeats step S500.

Next, the configuration including the objective lens 340 and the image sensor 350 detects a dot pattern formed on the display panel 210 at the pen tip position (S510). Here, the infrared light emitted from the illumination unit 380 is diffusely reflected in the display panel 210, and a part of the infrared light returns to the digital pen 300 side.

赤外 Infrared light returning to the digital pen 300 side hardly transmits through the dot 411 of the dot pattern. Infrared light that has mainly passed through the region between the dots 411 reaches the objective lens 340. The infrared light is received by the image sensor 350 through the objective lens 340. The objective lens 340 is disposed on the display panel 210 so as to receive reflected light from the position indicated by the pen tip portion 320. As a result, the dot pattern at the indicated position of the pen tip portion 320 on the display surface of the display panel 210 is imaged by the image sensor 350. Thus, the configuration including the objective lens 340 and the image sensor 350 optically reads the dot pattern. An image signal generated by the imaging of the image sensor 350 is transmitted to the pen side microcomputer 360.

Next, the pen side microcomputer 360 acquires the pattern shape of the dot pattern from the received image signal, and specifies the position of the pen tip on the display panel 210 based on the pattern shape (S520). Specifically, the pen side microcomputer 360 acquires the pattern shape of the dot pattern by performing predetermined image processing on the obtained image signal. Subsequently, the pen-side microcomputer 360 determines which unit area (6 dot × 6 dot unit area) from the arrangement of the dots 411 in the acquired pattern shape, and the position of the unit area from the dot pattern of the unit area. Specify coordinates (position information). The pen-side microcomputer 360 converts the dot pattern into position coordinates by a predetermined calculation corresponding to the dot pattern coding method.

Then, the pen-side microcomputer 360 transmits the specified position information to the display device 200 via the transmission unit 370 (S530). Thereby, the display apparatus 200 can grasp the pen tip position of the digital pen 300.

The position information transmitted from the digital pen 300 is received by the receiving unit 230 of the display device 200. The received position information is transmitted from the receiving unit 230 to the display-side microcomputer 240.

When the display-side microcomputer 240 receives the position information, the display-side microcomputer 240 performs a display operation corresponding to the display surface on the display panel 210. Specifically, the display-side microcomputer 240 controls the display panel 210 so as to change the display content of the position corresponding to the position information in the display area of the display panel 210. In this example, since a character is input, a point is displayed at a position corresponding to the position information in the display area of the display panel 210. When the pen input with the digital pen 300 is continued, the display-side microcomputer 240 continuously acquires the position information. Thereby, following the movement of the pen tip portion 320 of the digital pen 300, dots can be continuously displayed at the position of the pen tip portion 320 on the display area of the display panel 210. That is, characters corresponding to the locus of the pen tip portion 320 of the digital pen 300 can be displayed on the display panel 210.

In the above description, the case where characters are entered on the display surface has been described. However, the use of the display control system 100 is not limited to this. Of course, not only characters (numbers etc.) but also symbols and figures can be entered, but the digital pen 300 can be used like an eraser to erase characters and figures displayed on the display panel 210. You can also. Furthermore, using the digital pen 300 like a mouse, the cursor displayed on the display panel 210 can be moved, or the icon displayed on the display panel 210 can be selected. In other words, a graphical user interface (GUI) can be operated using the digital pen 300.

As described above, the first embodiment has been described as an example of the technique disclosed in the present application. However, the technology in the present disclosure is not limited to this, and can also be applied to an embodiment in which changes, replacements, additions, omissions, and the like are appropriately performed.

Accordingly, among the components described in the accompanying drawings and the detailed description, not only the components essential for solving the problem, but also the components not essential for solving the problem in order to illustrate the above technique. May also be included. Therefore, it should not be immediately recognized that these non-essential components are essential as those non-essential components are described in the accompanying drawings and detailed description.

In addition, since the above-described embodiment is for illustrating the technique in the present disclosure, various modifications, replacements, additions, omissions, and the like can be performed within the scope of the claims or an equivalent scope thereof.

The present invention can be applied to a display panel that forms a display control system together with an optical device that emits invisible light and receives reflected invisible light.

DESCRIPTION OF SYMBOLS 100 Display control system 200 Display apparatus 210 Display panel 230 Reception part 240 Display side microcomputer 250 Display side memory 300 Digital pen 310 Main body case 320 Pen tip part 330 Pressure sensor 340 Objective lens 350 Image sensor 360 Pen side microcomputer 370 Transmission part 380 Illumination 390 Pen side memory 400 Optical film 410 Dot pattern sheet (pattern layer)
411 dot 412 PET film 413 transparent medium layer 414 first reference line 415 second reference line 430 infrared reflection sheet 432 infrared reflection layer 433 uneven substrate 435 uneven surface average line (reference surface)
440 Touch sensor glass 450 Liquid crystal panel 451 Color filter layer 452 Color filter 453 Black matrix 460 Backlight device

Claims

A display panel that forms a display control system together with an optical device that includes an emission unit that emits invisible light and a light receiving unit that receives reflected invisible light,
In order for the optical device to specify the position information that the optical device points on the display panel, a pattern layer in which a pattern of dots is formed according to a predetermined rule;
A non-visible light reflecting layer that is disposed to face the pattern layer and reflects at least a part of the non-visible light emitted from the optical device to the optical device through the pattern layer;
The pattern layer and the non-visible light reflecting layer are connected by a transparent medium having a refractive index n, and from the tip of each dot forming the pattern layer on the side facing the non-visible light reflecting layer. The distance X to the average line of the surface shape of the invisible light reflecting layer is D, the average major axis of each dot forming the pattern layer, W, the average height difference of the surface shape of the invisible light reflecting layer, W / 2 ≦ X <D / tan [sin −1 , where θ (0 <θ <π / 2) is an angle formed by the optical axis of the emission unit and the optical axis of the light receiving unit of the optical device. A display panel that satisfies the expression {sin θ / n}].
The display panel according to claim 1, wherein the distance X satisfies an expression of W / 2 ≦ X <D / (2 × tan [sin −1 {sin θ / n}]).
The display panel according to claim 1, wherein the distance X satisfies an equation of X = W / 2.
A display panel that can use an optical device that emits invisible light and receives reflected invisible light,
A pattern layer in which a pattern of dots is formed;
A non-visible light reflecting layer disposed opposite to the pattern layer and reflecting at least part of the non-visible light emitted from the optical device to the optical device through the pattern layer;
A transparent medium having a refractive index n provided between the pattern layer and the invisible light reflection layer;
With
The distance X from the surface facing each non-visible light reflecting layer of each dot forming the pattern layer to the average line of the surface shape of the non-visible light reflecting layer is the average major axis of each dot forming the pattern layer Where D is the average height difference of the surface shape of the invisible light reflecting layer, and W / 2 ≦ X <D / tan (sin −1 [{sin (π / 4)} / n]) A display panel that satisfies the formula.
The display panel according to claim 4, wherein the distance X satisfies an expression of W / 2 ≦ X <D / {2 × tan (sin −1 [{sin (π / 4)} / n])}.
The display panel according to claim 4, wherein the distance X satisfies a formula of X = W / 2.