JP2009288956A - Organic el display device with touch panel function - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic EL display device with touch panel function that is thin by dispensing with separate external members on the device. <P>SOLUTION: The organic EL display device includes, on a substrate 11, organic light emitting elements 15 including a light emitting element capable of emitting infrared light, and an infrared sensor 16. Infrared light can be emitted during image display, and when a pointing object 14 is in proximity to or contact with a display surface 13, the infrared sensor 16 reads information on the intensity of reflected light to acquire information on the position of the pointing object 14. The emission of infrared light from the organic light emitting element and the arrangement of the infrared sensor in the display area can dispense with separate external members on the device to add a touch panel function without any thickness increase. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an organic EL display device having a touch panel function.

  Since the organic EL display device is a self-luminous device, there is a feature that a backlight used in the liquid crystal display device is unnecessary, and there is an advantage that a thinner and lower power consumption can be realized.

  In recent years, a display device such as an organic EL or liquid crystal and a touch panel are often used in an integrated manner, and a user can input information easily and intuitively. The touch panel is an input device for detecting the position of a place where contact is made with a finger or a pen.

Conventionally, an organic EL display device having a touch panel function is disclosed in Patent Document 1. FIG. 8 shows a cross section of the display device shown in the embodiment. Among them, a configuration is proposed in which organic light emitting elements 5 that emit infrared light are arranged in an array on one side of the peripheral non-display area of the display device, and infrared light sensors 6 are arranged in an array on the opposite side. Has been. Light emitted from the organic light emitting element 5 that emits infrared light is reflected by a 45 degree mirror 7 disposed above the light emitting element and passes through the display surface. The light is reflected by a 45 degree mirror 7 disposed above the infrared light sensor and reaches the infrared light sensor 6. When an object comes close to the display surface, infrared light is shielded at that location, so that the position information of the object is calculated from the detection result of each infrared light sensor. This position detection means is well known as an infrared shielding method.
JP 2004-227576 A

  However, since the above-described method is a configuration in which a separate optical element is provided above the peripheral non-display area of the display device, the thickness of the entire display device increases.

  In particular, an organic EL display device does not require a backlight unit unlike a liquid crystal display device, and a separate external member is required above the display surface in order to fully exhibit the advantage of being thin. A touch panel method is desired.

  The present invention has been made in view of the above, and an object thereof is to provide an organic EL display device to which a touch panel function is added without increasing the thickness of the device.

  In order to achieve the above object, the following is provided.

A substrate,
A plurality of organic light emitting devices disposed in a display area on the substrate;
A surface substrate for protecting the organic light emitting device;
In an organic EL display device having an arithmetic circuit that calculates position information of an object that approaches or contacts the surface substrate,
The plurality of organic light emitting elements include elements that emit infrared light,
The infrared light sensor that receives the infrared light reflected by the object is disposed in a region different from the organic light emitting element in the display region,
The organic EL display device, wherein the arithmetic circuit calculates position information of the object based on an output result of the infrared light sensor.

An organic EL display device with a touch panel function according to the present invention,
Infrared light is emitted from the organic light emitting device itself, and an infrared light sensor is placed in the pixel, so no additional external member is required above the device, and a touch panel function is added without increasing the thickness. It is possible to make it.

  Examples will be described below.

  An embodiment of an organic EL display device according to the present invention is shown in FIG. An organic light emitting element 15 including an infrared light emitting element and an infrared light sensor 16 are formed in a display region 21 (see FIG. 7) on the substrate (substrate 11). Note that a combination of a plurality of material layers such as a hole injection layer, a hole transport layer, an electron injection layer, and an electron transport layer, electrodes, and an organic light emitting layer, which are well known in the technical field, is referred to as an organic light emitting element. ing.

  Further, a thin film transistor (TFT, Thin Film Transistor) that actively drives the organic light emitting element 15 is included in the substrate 11.

  Further, FIG. 2 is a diagram in which the positional relationship between the light emitting element 15 and the infrared light sensor 16 in the display region is viewed from the normal direction of the display surface. In one pixel, one pixel is divided into four, and within each pixel, organic light emitting elements that emit red light 15R, green 15G, blue 15B, and infrared 15IR are arranged. . In one pixel, an infrared light sensor 16 is arranged in addition to the red light emitting element 15R, the green light emitting element 15G, and the blue light emitting element 15B. Actually, a plurality of these pixels are two-dimensionally arranged in a matrix to function as a display device that performs various displays. In particular, by arranging the infrared light sensor 16 and the organic light emitting elements that emit infrared light in a matrix, it is possible to improve the detection accuracy of the position information of the pointing object 14 described in detail later.

  Further, the arrangement of the light emitting elements and the infrared light sensor is not limited to this, and an arrangement in which a pixel is divided into four tiles as shown in FIG. 3 may be used.

  Further, as shown in FIG. 4, the infrared light emitting element 15IR and the infrared light sensor 16 may be included in the same pixel.

  Note that each of the sub-pixels and the infrared light sensor region is separately applied to a display device having a configuration of four sub-pixels (each emission color is, for example, green, red, green, and blue) that is well known in the art. The manufacturing method can be applied.

  Moreover, it is preferable that the light emission peak wavelength of an infrared light emitting element is 700 nm or more.

  It is preferable to use an infrared light sensor 16 having an optical filter having a wide wavelength sensitivity including an infrared region, such as a silicon phototransistor, and transmitting only infrared light in a wavelength range of 700 nm or more. . This is to suppress light reception noise caused by visible light during sensing.

  Here, the configuration and manufacturing process of the TFT will be described with reference to FIG.

  Amorphous silicon deposited on the insulating glass substrate 101 is used as a starting point, and crystallized using a laser annealing method to form semiconductor layers (collectively 102, 103, and 104). Then, chromium or molybdenum which is a refractory metal is formed as the gate electrode 106 with the gate insulating film 105 interposed therebetween. By performing ion doping on the semiconductor layers (102, 103, 104), the source 102 and the drain 103 are formed on both sides of the active layer 104. Further, an inorganic insulating interlayer insulating film 107 is formed and a contact hole is opened. Then, a metal such as aluminum is disposed as the source electrode 108 and the drain electrode 109 in contact with the source 102 and the drain 104. Further, a protective film 110 made of an organic resin is formed on the surface, and the anode 111 of the organic light emitting element 15 made of, for example, ITO (indium tin oxide) is disposed so as to be in contact with the source electrode 108.

  The configuration of the optical sensor 16 will be described with reference to FIG.

  Since the transistor configuration is basically the same as that of the TFT for driving the organic light emitting element 15 shown in FIG. 5, the manufacturing process is omitted. In particular, the TFT shown in FIG. 5 is a so-called top gate type in which the gate electrode is disposed on the opposite side of the substrate through the semiconductor layer, but in FIG. 6, the so-called bottom in which the gate electrode is disposed on the substrate side. This is a gate type. This is because it is preferable that the light receiving surface of the photosensor is not shielded by the gate electrode.

  Next, the position information of the object obtained by the optical sensor 16 will be described.

  In FIG. 1, when the pointing object 14 such as a human finger or a touch pen contacts or approaches the surface substrate 13 of the display device, the light emitted from the infrared light emitting element 15 is reflected on the pointing object 14 and the reflected light is reflected. The infrared light sensor 16 receives light. A mechanism for detecting the contact or proximity of an object at this time will be described with reference to FIG.

  The infrared light sensors 16 arranged two-dimensionally are sequentially scanned to receive reflected light at a predetermined interval. The intensity information of the light received by the infrared light sensor 16 is output as an analog electric signal by the sensor control device 22 through an amplifier. Thereafter, based on the output result, the calculation circuit (that is, the external data output circuit 24 and the control LSI 25) calculates the contact or proximity position of the pointing object 14.

  Here, the external data output circuit 24 converts the amplified analog electric signal into a digital signal. The external control LSI 25 performs data analysis and calculation of contact positions (including proximity positions). The detection of the presence or absence of contact or proximity is determined by analyzing time-series output data.

  In this configuration, the light emitting element 15 is sealed by the surface substrate 13 (glass substrate). However, any member having transparency to visible light and infrared light may be used, and a silicon nitride film, a silicon oxynitride film, It may be sealed with an inorganic insulating film made of a silicon oxide film.

  In this configuration, the infrared light emitting element 15IR and the infrared light sensor 16 are arranged for each pixel. However, the infrared light emitting element 15IR and the infrared light sensor 16 are equally spaced at a rate of one for a plurality of pixels within a range that does not hinder the position detection. A configuration arranged in the above may be used.

  Further, in this configuration, a protective member such as an acrylic plate may be provided on the surface substrate 13 in order to protect the surface substrate 13.

  Further, an antireflection film or a polarizing plate may be provided on the surface substrate 13 in order to suppress the reflection of external light and improve the visibility of the display device.

  The above-described embodiment is a so-called top emission type application example in which light is emitted from the surface substrate 13 side, but the present invention is not limited to this, and light is emitted from the substrate 11 side. You may apply to what is called a bottom emission type.

It is sectional drawing which showed embodiment of the organic electroluminescent display apparatus in this invention. It is arrangement | positioning with an organic light emitting element and an infrared-light sensor in embodiment of this invention. 3 is another arrangement of FIG. 3 is another arrangement of FIG. It is a figure explaining the structure of TFT which drives an organic light emitting element. It is a figure explaining the structure of an optical sensor. It is a block diagram explaining the mechanism which detects the position of a contact thing. This is an organic EL display device having a conventional position detecting means by an infrared light shielding method in which an infrared light emitting element and an optical sensor are formed on a substrate and an optical element is provided at a display peripheral edge.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Substrate 2 Sealing substrate 3 Emission light 4 Organic light emitting device 5 Organic light emitting device that emits infrared light 6 Infrared light sensor 7 Mirror 11 First glass substrate 13 Second glass substrate (surface substrate)
15 Organic light emitting devices (R, G, B, IR)
16 Infrared Light Sensor 21 Display Area 22 Sensor Control Device 23 Light Emitting Element Drive Device 24 Data Output Circuit 25 Control LSI
DESCRIPTION OF SYMBOLS 101 Glass substrate 102 Source 103 Drain 104 Active layer 105 Gate insulating film 106 Gate electrode 107 Interlayer insulating film 108 Source electrode 109 Drain electrode 110 Protective film 111 Anode of organic light emitting device

Claims (3)

A substrate,
A plurality of organic light emitting devices disposed in a display area on the substrate;
A surface substrate for protecting the organic light emitting device;
In the organic EL display device having an arithmetic circuit for calculating position information of an object in contact with or close to the surface substrate,
The plurality of organic light emitting elements include elements that emit infrared light,
The infrared light sensor that receives the infrared light reflected by the object is disposed in a region different from the organic light emitting element in the display region,
The organic EL display device, wherein the arithmetic circuit calculates position information of the object based on an output result of the infrared light sensor.   The organic EL display device according to claim 1, wherein the infrared light sensors are arranged in a matrix on the substrate.   The organic EL display device according to claim 1, wherein the infrared light sensor and the element that emits the infrared light are arranged in one pixel.

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