WO2002065394A1 - Fingerpirnt image input device having display function - Google Patents

Abstract

A fingerprint image input device has a substrate, signal sensing electrodes arranged on one side of the substrate, and light-emitting elements arranged on the same side of the substrate. The capacitance between the signal sensing electrodes and a finger is measured, and according to the result of the measurement, the mode is switched between a fingerprint input mode for capturing a fingerprint image and a fingerprint image display mode for displaying the fingerprint image by causing the light-emitting elements to emit light depending on the capacitance.

Description

 TECHNICAL FIELD The present invention relates to a fingerprint image input device having a display function.

 The present invention relates to a fingerprint image input device having a display function, and more particularly to a fingerprint image input device having a built-in image display function suitable for application to portable devices such as portable information terminals, mobile phones, and personal computers. is there. Conventional technology

 A method using a fingerprint has been widely used as one of the means for individually identifying a person, and an electrostatic fingerprint image input method is known as one of the methods. FIG. 17 is a perspective view of a fingerprint image input device disclosed in Japanese Patent No. 2959532 as an example of a conventional capacitance detection type fingerprint image input device.

 This fingerprint image input device includes a signal generation / detection substrate 100 and a high frequency generation source 108. The signal generation / detection substrate 100 includes an insulating substrate 101, a signal generating electrode 102 formed in a mesh on the insulating substrate 101, and a plurality of signal detecting electrodes formed in a matrix on the insulating substrate 101. 103, a shift register circuit 109 formed along one side of the insulating substrate 101, and a signal formed along a side orthogonal to the one side on which the shift register circuit 109 is formed. The high-frequency generation source 108 is connected to the signal generation electrode 102.

 FIG. 18 is a schematic configuration diagram of the conventional fingerprint image input device shown in FIG. 17, and FIG. 19 shows the capacitance formed in the components of the conventional fingerprint image input device shown in FIG. It is sectional drawing explaining.

As shown in FIG. 18 and FIG. 19, a plurality of thin film transistors (TFT: Thin Film Transistor) Tr are two-dimensionally arranged on the insulating substrate 101. A first insulating layer 106 is formed on the insulating substrate 101 so as to cover the plurality of thin film transistors Tr. Further, on the first insulating layer 106, The signal generating electrodes 102 are formed in a net shape. A signal detection electrode 103 is arranged in a blank portion between the meshes of the signal generation electrodes 102, and each signal detection electrode 103 is connected to a source electrode of the thin film transistor Tr.

 On the first insulating layer 106, a second insulating layer 107 is formed so as to cover the signal generating electrode 102 and the signal detecting electrode 103.

 The gate electrodes of all the thin film transistors Tr belonging to the same row are connected to the output terminals of the shift register circuit 109 via the gate electrode wiring 104, and all the thin film transistors T r belonging to the same column are connected. The drain electrode of r is connected to the input terminal of the signal detection circuit 110 via the drain electrode wiring 105. Next, the operation of the conventional fingerprint image input device shown in FIG. 17 will be described with reference to FIGS.

 When inputting a fingerprint, the tip of the finger F to be input is brought into contact with the surface of the signal generation / detection substrate 100.

 After that, the first output of the shift register circuit 109 is set to the H level, and all the signal detection electrodes 103 belonging to the first row are connected to the signal detection circuit 110 via the drain electrode wiring 105. Electrically connected to

 Here, when a high frequency signal is applied to the signal generating electrode 102 by the high frequency source 108, the signal is detected via the three capacitances C1, C2, and Cd shown in FIG. Charge is applied to the electrode 103. The capacitances C l, C 2 and C d are respectively formed between the finger F and the signal detection electrode 103 and between the signal generation electrode 102 and the finger. This is the capacitance formed between the signal generation electrode 102 and the signal detection electrode 103.

 Here, if the signal generation electrode 102, the signal detection electrode 103, and the high-frequency signal are designed so that C2 >> C1, the amount of charge applied to the signal detection electrode 103 is almost electrostatic. It is proportional to the capacity C1. Since the capacitance C 1 is determined by the undulation of the finger F near the signal detection electrode 103, that is, the ridges and valleys, the output of the signal detection circuit 110 is the output of the finger F in the first row. The undulation information, that is, the information of the ridges and valleys of the finger F is reflected.

The fingerprint information obtained by the thin-film transistor Tr in the first row in this manner is externally stored. After recording in the memory, the same operation is repeated for the thin film transistors Tr in the second and subsequent rows, whereby a fingerprint image of the finger F can be obtained.

 When the fingerprint image input device is mounted on a portable device such as a mobile phone or a portable information terminal, it is desirable that the volume, that is, the area and the thickness of the fingerprint image input device be as small as possible.

 However, an electrostatic fingerprint image input device requires at least an area large enough to press the finger F. Furthermore, considering the ease of pressing the finger F, the fingerprint image input device It is desirable that the area of the device is sufficiently larger than the area of the fingerprint to be input.

 As a solution to such contradictory requirements, a method has been proposed in which a fingerprint image input device is formed by stacking it on the surface of a liquid crystal display or other display device. This has the advantage that the operation of superimposing the actual finger on the figure of the finger displayed on the surface of the display device ensures the fingerprint input operation, and is excellent in usability. By using an insulating substrate 101 of the electrostatic fingerprint image input device shown in Fig. 17 as a transparent substrate made of glass or other transparent material, such a stacked display / image input device is realized. can do.

 However, this stacked display image input device has the following problems.

 The first problem is that the light use efficiency is low.

 For example, as shown in FIG. 18, even if the signal generating electrode 102 and the signal detecting electrode 103 are formed of a transparent material, the gate electrode wiring 104 and the drain electrode wiring 105 are opaque. It is difficult to make the light transmittance of the image input device 100% because it is formed of a simple metal material.

 Therefore, part of the light emitted from the light source is blocked by opaque components such as the gate electrode wiring 104 and the drain electrode wiring 105 of the image input device, and does not reach the observer. For this reason, it is necessary to choose between accepting that the displayed image is dark or accepting an increase in power consumption by increasing the output of the light source.

As described above, the stacked display / image input device has a problem that the light use efficiency is low. The second problem is that it is impossible to reduce the thickness of the display image input device. The thickness of the stacked display / image input device is the sum of the thicknesses of the stacked components, and it is impossible to further reduce the thickness. For example, if the thickness of a liquid crystal display is 1.4 mm and the thickness of a fingerprint input device is l mm, the thickness of the display image input device will be 2.4 mm, and further reduction in thickness is impossible.

 The third problem is that an increase in the number of manufacturing processes cannot be avoided. If a TFT-type liquid crystal display capable of displaying high-quality images is used, a transparent substrate in which many TFTs are arranged for both the liquid crystal display and the fingerprint image input device is required. A total of 2 boards are required. Therefore, it is not possible to avoid an increase in the manufacturing process and manufacturing time due to the TFT manufacturing, and an increase in the manufacturing cost.

In addition to the above-mentioned Japanese Patent No. 29595332, Japanese Patent No. 2939570/2006 discloses (a) a planar light source, and (b) disposed above the planar light source. A photoelectric conversion element that outputs a photoelectric signal in response to light from the planar light source; and a photoelectric conversion element that is provided near the photoelectric conversion element and that turns on and off the photoelectric signal in response to a scanning signal; A bias line for supplying a bias voltage to each of the photoelectric change elements, a pixel connection line including a data line and a scan line for transmitting the photoelectric data signal and the scan signal, respectively, and the scan. A two-dimensional image sensor comprising: a scanning unit that supplies a signal; and a photoelectric data detecting unit that detects the photoelectric data signal; and (c) the photoelectric conversion element, the switch element, the bias line, and the data line. Transparent parts other than Optical means for guiding light transmitted through a certain opening to irradiate a finger to be subjected to a fingerprint image input, and guiding reflected light from the finger to the photoelectric conversion element; and (d) the finger with respect to the surface of the two-dimensional image sensor. Finger signal generating means for supplying a finger detection signal for detecting the contact of the finger, and (e) finger contact detection means for detecting a change in the finger detection signal in response to the contact of the finger, the two-dimensional image First and second switches for selectively connecting each of the finger signal generation means and the finger contact detection means to one end and the other end of one of the pixel connection lines in response to supply of a control signal; And a switch control means for outputting the control signal corresponding to the detection of the finger contact and the input of the fingerprint image. Japanese Patent Application Laid-Open No. H08-305832 discloses an electrode provided on a surface, a detection circuit connected to each of these electrodes and detecting the capacitance of each electrode, and a finger on the surface. A fingerprint input device for obtaining an image pattern of ridges and valleys of the fingerprint of the finger according to the magnitude of the capacitance of each electrode detected when the finger is brought into contact with or close to the finger. Has been proposed.

 Also, Japanese Patent Application Laid-Open No. H10_1494446 discloses a data processing circuit for extracting features of image information taken in from a fingerprint detection unit, a feature amount processed by the data processing circuit, and a storage device. Proposed a fingerprint collation device equipped with a comparator for comparing data stored in a device with data whose features have been extracted in advance.

 Japanese Patent Application Laid-Open No. H10-32689 discloses a light-transmitting substrate, a light-emitting substrate that transmits the light-transmitting substrate, and emits light for irradiating an object pressed against the light-transmitting substrate. A plurality of light-receiving members provided on the light-transmitting substrate at intervals in the vertical and horizontal directions, for receiving reflected light of light illuminating the subject; There has been proposed an image reading apparatus including: reading means for reading an image of a subject;

 Japanese Patent Application Laid-Open No. H11-12553-428 discloses a scanning fingerprint detection system in which an array including capacitive detection elements is provided, wherein the array has a first dimension about the width of a fingerprint, and a fingerprint. A second dimension that is shorter than the length, and each of the capacitive sensing elements has a dimension that is smaller than the width of a fingerprint ridge, and the capacitative sensing element is configured to capture an image of a portion of the fingerprint. A scanning fingerprint detection system is proposed in which means are provided for scanning the array, and wherein means are provided for assembling the captured image into a fingerprint image as the fingerprint is moved over the array.

 However, even with the device proposed in the above publication, the above-mentioned problem has not been solved.

The present invention has been made in view of the above-described problems of the conventional image input device, and has a thin display function that can be driven with high light use efficiency, consumes low power consumption, and does not cause an increase in the number of manufacturing processes. It is an object of the present invention to provide an image input device incorporating a personal computer. Disclosure of the invention

 In order to achieve the above object, the present invention provides a substrate, a plurality of signal detection electrodes arranged on one plane of the substrate, and an arrangement on the same plane as the plane on which the signal detection electrodes are arranged. A plurality of light emitting elements; a fingerprint image input mode for obtaining a fingerprint image by detecting a capacitance formed between the signal detection electrode and a finger; and the light emission according to the capacitance. Provided is a fingerprint image input device capable of switching a fingerprint image display mode for displaying the fingerprint image by causing the element to emit light.

 It is preferable that the above fingerprint image input device is provided with a protective layer that can be brought into contact with a finger and that covers the signal detection electrode and the light emitting element. In the above fingerprint image input device, when inputting the fingerprint image, it is preferable that a part of a wiring for driving the light emitting element is used as a signal wiring for detecting the capacitance. .

 In the above fingerprint image input device, it is preferable that the light emitting elements are arranged in a matrix in a one-to-one correspondence with the signal detection electrodes.

 The fingerprint image input device may include: a plurality of scanning signal wirings arranged on the substrate; a plurality of data signal wirings arranged on the substrate at right angles to the scanning signal wirings; A first switch element connected to the data signal wiring and connected to the signal detection electrode; a second switch element connected to the scanning signal wiring and the data signal wiring; And a current control element connected to the second switch element, wherein the light emitting element is preferably connected in series to the current control element.

 The fingerprint image input device includes: a power supply line disposed on the substrate; and a ground line disposed on the substrate. The light emitting element and the current control element are connected in series. And the other side is preferably connected to the ground wiring.

 The fingerprint image input device further includes a signal generation electrode to which either the power supply wiring or the ground wiring is connected when the fingerprint image is input, and the signal generation electrode includes a high-frequency signal. Is preferably applied.

In the above fingerprint image input device, when inputting the fingerprint image, It is preferable that a scanning signal overlapping with another scanning signal wiring adjacent to the scanning signal wiring for a predetermined time is sequentially applied to each of the inspection signal wirings.

 The above fingerprint image input device may include a mode switching switch element, a display driving circuit to which one end of the data signal wiring is connected via the mode switching switch element, and the other end of the data signal wiring. It is preferable to include an image input detection circuit connected via a mode switching switch element, and a display / image input drive circuit connected to one end of the scanning signal wiring.

 In the above fingerprint image input device, the display drive circuit, the image input detection circuit, and the display image input drive circuit are formed of a thin film transistor formed on the substrate. Is preferred.

 In the above fingerprint image input device, it is preferable that the light emitting element is formed using an organic electroluminescent material.

 In the above fingerprint image input device, the substrate is a transparent substrate, the lower electrode of the light emitting element is formed of a transparent conductive film, and light emitted from the light emitting element is radiated from the back surface of the substrate. Preferably.

 In the above fingerprint image input device, it is preferable that an upper electrode of the light emitting element is formed of a transparent conductive film, and that light emitted from the light emitting element is emitted above the substrate. '

 It is preferable that the lower electrode or the electrode opposite to the upper electrode is formed of a metal material having a high light reflectance.

 The fingerprint image input device according to the present invention described above can be applied to various devices. The invention provides a first housing, a second housing connected to the first housing via a hinge mechanism so as to be foldable, and the fingerprint image input device described above. Wherein the fingerprint image input device is configured such that when the first housing and the second housing are folded together, the fingerprint image input surface of the substrate is the first housing or the second housing. It is incorporated in one of the first housing and the second housing so that either one of the outside and the inside of the body faces and the fingerprint image display surface of the substrate faces the other. Provide equipment.

Further, the present invention provides a first housing, and the first housing, the first housing being interconnected via a hinge mechanism. And a fingerprint image input device as described above, wherein the fingerprint image input device connects the first housing and the second housing to each other. The first housing so that when folded, the fingerprint image input surface and the fingerprint image display surface of the substrate face either the outside or the inside of the first housing or the second housing. And a device incorporated in any one of the second housings. As such a device, for example, a mobile phone device can be selected. The present invention further includes a step of touching a finger on the one plane of the fingerprint image input device in which a plurality of signal detection electrodes are arranged on one plane of a substrate; and forming between the signal detection electrode and the finger. Providing a fingerprint image by detecting a capacitance of the fingerprint image.

 When the fingerprint image input apparatus further includes a plurality of light emitting elements arranged on the same plane as the plane on which the signal detection electrodes are arranged, the present fingerprint image input method may be configured according to the capacitance. Preferably, the method further includes the step of displaying the fingerprint image by causing the light emitting element to emit light. BRIEF DESCRIPTION OF THE FIGURES

 FIG. 1 is a perspective view of an image input device according to a first embodiment of the present invention.

 FIG. 2 is a plan view (FIG. 2A) of a unit pixel and an equivalent circuit diagram thereof (FIG. 2B) in the image input device according to the first embodiment of the present invention.

 FIG. 3 is a sectional view of a unit pixel in the image input device according to the first embodiment of the present invention.

 FIG. 4 is a sectional view (FIG. 4 (A)) and an equivalent circuit diagram (FIG. 4 (B)) for explaining the capacitance formed in the image input device according to the first embodiment of the present invention. . FIG. 5 is a timing chart for explaining the operation of the image input apparatus according to the first embodiment of the present invention.

 FIG. 6 is a cross-sectional view (FIG. 6 (A)) and a plan view (FIG. 6 (B)) showing one manufacturing process stage of the image input device according to the first embodiment of the present invention.

FIG. 7 is a cross-sectional view (FIG. 7 (A)) and a plan view (FIG. 7 (B)) showing one manufacturing process stage of the image input device according to the first embodiment of the present invention. FIG. 8 is a cross-sectional view (FIG. 8 (A)) and a plan view (FIG. 8 (B)) showing one manufacturing process stage of the image input device according to the first embodiment of the present invention.

 FIG. 9 is a cross-sectional view (FIG. 9 (A)) and a plan view (FIG. 9 (B)) showing one manufacturing process stage of the image input device according to the first embodiment of the present invention.

 FIG. 10 is a sectional view (FIG. 10 (A)) for explaining the capacitance formed in the image input device according to the second embodiment of the present invention and an equivalent circuit diagram thereof (FIG. 10 (B)). ). FIG. 11 is a cross-sectional view (FIG. 11 (A)) for explaining the capacitance formed in the image input device according to the third embodiment of the present invention and its equivalent circuit diagram (FIG. 11 (B)). ). FIG. 12 is an evening timing chart for explaining the operation of the image input device according to the third embodiment of the present invention.

 FIG. 13 is a plan view (FIG. 13 (A)) and a sectional view (FIG. 13 (B)) of a unit pixel in the image input device according to the fourth embodiment of the present invention.

 FIG. 14 is a plan view (FIG. 14 (A)), an equivalent circuit diagram (FIG. 14 (B)), and a sectional view (FIG. 1) of a unit pixel in the image input device according to the fifth embodiment of the present invention. 4 (C)). FIG. 15 is a perspective view of a mobile phone according to a sixth embodiment of the present invention.

 FIG. 16 is a perspective view of a mobile phone according to a seventh embodiment of the present invention.

 FIG. 17 is a perspective view of a conventional fingerprint image input device of the capacitance detection type.

 FIG. 18 is a configuration diagram of the conventional electrostatic capacitance detection type fingerprint image input device shown in FIG.

 FIG. 19 is a cross-sectional view illustrating the capacitance formed in the conventional capacitance detection type fingerprint image input device shown in FIG. Detailed Description of the Preferred Embodiment

 Next, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)

 FIG. 1 is a perspective view of a fingerprint image input device having a display function according to a first embodiment of the present invention.

The fingerprint image input device 10 according to the present embodiment includes a transparent substrate 11, a plurality of signal detection electrodes 28 arranged in a matrix on the transparent substrate 11, and a matrix on the transparent substrate 11. A plurality of light emitting elements 1 arranged in a matrix, a display drive circuit 2 formed along three sides around the transparent substrate 1, a display Z image input drive circuit 3, and an image input detection A circuit 4, a gate line 18 extending between the display drive circuit 2 and the image input detection circuit 4 so as to partition the formation region of the signal detection electrode 28 and the light emitting element 1, and a display drive circuit 2 , A data line 23 extending perpendicular to the gate line 18, a signal detection electrode 28, a light emitting element 1, a display drive circuit 2, a display / image input drive circuit 3, an image input detection circuit 4, A protective layer 29 covering the transparent substrate 11 so as to cover the gate line 18 and the data line 23.

 As shown in FIG. 2 (A), a GND line 27 is formed on the light emitting element 1, and a signal generating electrode / power supply line 20 is formed alongside the data line 23.

 In FIG. 1, one pixel as a display device is configured by arranging one red, one green, and two blue light emitting elements in a square shape. In FIG. 1, R, G, and B are added in parentheses after the reference number 1 to indicate the color emitted from the light emitting device. That is, R, G, and B represent red, green, and blue, respectively.

 Here, the reason for using two blue elements is to balance blue with other colors because blue has a lower light quantity or luminance than other red and green elements.

 Also, one signal detection electrode 28 is arranged for one light emitting element 1. The display drive circuit 2, display / image input drive circuit 3, and image input detection circuit 4 formed in the peripheral portion of the transparent substrate 1 are formed using a polycrystalline silicon (poly-Si) TFT. However, it is particularly desirable that the CMOS circuit be configured using both an n-type TFT and a p-type TFT.

 FIG. 2A is a layout diagram showing one light emitting element unit of the pixel shown in FIG. 1, and FIG. 2B is an equivalent circuit diagram thereof.

As shown in FIG. 2A, three thin film transistors of a first thin film transistor Tr1, a second thin film transistor Tr2, and a third thin film transistor Tr3 are formed in one light emitting element unit of a pixel. . The gate wiring 17 connected to the source of the second thin film transistor Tr 2 and serving as the gate electrode of the third thin film transistor Tr 3 is formed so as to partially overlap the signal generating electrode and power supply line 20, A capacitor C is formed in the overlapping portion. Further, the light emitting element 1 includes a transparent electrode 25, a light emitting material layer 26, and a portion of a GND line 27 (see FIG. 3).

 The gate of the first thin film transistor Tr1 for detecting the electric charge applied to the signal detection electrode 28 is connected to the gate line 18, the drain is connected to the data line 23, and the source is connected to the signal detection electrode 28, respectively.

 Further, the gate of the second thin film transistor Tr 2 for charging the capacitor C is connected to the gate line 18, the drain is connected to the data line 23, and the source is connected to one terminal of the capacitor C as described above. It is connected to the gate of the third thin film transistor Tr3.

 The other terminal of the capacitor C and the source of the third thin film transistor Tr 3 are connected to the signal generation electrode / power supply line 20, and the drain of the third thin film transistor Tr 3 is connected to the anode of the light emitting element 1.

 The cathode of the light emitting element 1 is connected to the GND line 27.

 As shown in Fig. 2 (B), the circuit that constitutes the pixel is connected to four types of wiring, namely, GND line 27, gate line 18, power supply line 20 also serving as signal generating electrode, and data line 23. Have been. Some of these wires, that is, the gate line 18 and the data line 23, are common in both the display mode in which display is performed by the light emitting element 1 and the image input mode in which the charge of the signal detection electrode 28 is detected. Used for Further, the signal generation electrode / power supply line 20 is used as a power supply line in the display mode and as a signal generation electrode in the image input mode.

 The layout in which one wiring is used in both the display mode and the image input mode in this way is to reduce the area occupied by the wiring and increase the area of the signal detection electrode 28 and the light emitting element 1. This is to make it possible.

The display resolution is 200 pp i (pi xe 1 / i n ch, that is, the number of pixels per inch when three color light emitting elements of red, green, and blue are regarded as one pixel) (200 pi X e 1 / inch = 7.87 pixe 1 mm) and the resolution of fingerprint input is set to 400 dpi (dot / inch, that is, the number of image input devices per inch) (400 dot / inch = 15.75 dot / mm). In this case, the layout pitch in the horizontal and vertical directions in Fig. 2 (A) is 63.5 m. FIG. 3 is a cross-sectional view showing main components of the image input device 10 according to the first embodiment of the present invention. However, FIG. 3 is a diagram for easily illustrating the state of the light emitting element 1 and the signal detection electrode 28 and the thin film transistor connected to them, and is not necessarily the configuration of the layout diagram shown in FIG. No match.

 In the following, a configuration using an organic electroluminescent (Electroluminumsenecse: EL) material as the light emitting element 1 will be described as an example. As shown in FIG. 3, the light emitting element 1 has a light emitting material layer 26 formed of an organic EL material as a light emitting layer, and a transparent electrode 25 as a lower electrode of the light emitting material layer 26 as one electrode (anode). The GND line 27 formed so as to cover the material layer 26 is configured as the other electrode (negative electrode). '

 When a positive potential difference is applied between the transparent electrode 25 and the GND line 27 so that the anode side is positive, a current flows through the luminescent material layer 26 in a region sandwiched between the electrodes 25 and 27, and the transparent electrode 25 and Light is emitted through the second interlayer insulating film 24, the first interlayer insulating film 19, and the transparent substrate 11. ′ The transparent electrode 25, which is the lower electrode of the light emitting element 1, is connected to one of the source / drain regions 15 of the third thin film transistor Tr 3 via the source electrode 21. The signal detection electrode 28 is connected to one of the source / drain regions 15 of the first thin film transistor Tr 1 via the source electrode 22. The other source / drain region 15 of the third thin film transistor Tr 3 and the first thin film transistor Tr 1 is connected to a signal generation electrode / power supply line 20 and a data line 23, respectively. In the present embodiment, a thin film transistor adopts a top gate type polycrystalline silicon (p0y-Si) TFT structure in which a gate electrode is formed on a channel region.

 Although not shown in FIG. 3, in the present embodiment, the gate wiring 17 and the power supply line 20 also serving as a signal generating electrode overlap with the first interlayer insulating film 19 interposed therebetween in the region shown in FIG. 2A. Thus, the capacitor C is formed.

 The detailed configuration and manufacturing method of the main components such as the TFT and the light emitting element will be described later.

FIG. 4B is a circuit diagram showing a circuit configuration of the image input device according to the first embodiment of the present invention. It is a road map.

 The gate line 18 is derived from the display Z image input drive circuit 3, and one end of the data line 23 is connected to the sixth thin film transistor Tr 6 in the display drive circuit 2 and the other end is connected to the image input detection circuit 4. It is connected to the seventh thin film transistor Tr7. For convenience of explanation, # 2 n to # 2 (n + 1) are assigned to the gate line 18, and # 2m to # 2 (m + 1) are assigned to the data line 23 and the circuit corresponding to each data line. Numbered.

 The sixth thin-film transistor Tr 6 and the seventh thin-film transistor Tr 7 provided in the display driving circuit 2 and the image input detection circuit 4 are switches for switching between the display mode and the image input mode, respectively. Only one of the circuits is electrically connected to the data line 23 by the switching signals DI SP and DI SPbar.

 For example, when selecting the display mode, the mode switching signal DI SP is set to the H level, all the data lines 23 are connected to the display drive circuit 2, and then the video signal to be displayed from the display drive circuit 2 is displayed. Are supplied to the data lines 23 # 2m to # 2 (m + 1) one row at a time.

 On the other hand, in the image input mode, the mode switching signal DISPbar becomes H level, and all the data lines 23 are electrically connected to the image input detection circuit 4. The image input detection circuit 4 includes amplifiers AMP 2m to # 2 (m + 1) connected to the individual data lines 23. The outputs of these amplifiers 2m to # 2 (m + 1) are configured to be sequentially output to the outside by running signals CLM2m to # 2 (m + 1).

 In addition, the display Z image input driving circuit 3 sequentially switches the first thin film transistor Tr1 and the second thin film transistor Tr2 sharing the gate line one row at a time in both the display mode and the image input mode. It is configured to be selectable.

A characteristic point of the image input device according to the present embodiment is that two kinds of voltages, POWER (power supply voltage) and CHARGE (high-frequency signal), are switched by the fourth thin film transistor Tr 4 and the fifth thin film transistor Tr 5 to generate a signal. Marked on electrode / power line 20 This is the point that the configuration is added.

 FIG. 4A is a cross-sectional view for explaining the capacitance formed in the image input device according to the present embodiment, and FIG. 5 is an image input device according to the first embodiment of the present invention. 3 is a timing chart for explaining the operation of FIG.

 Hereinafter, the operation of the fingerprint image input device 10 according to the present embodiment will be described with reference to FIGS. In this embodiment, when the display mode is selected, the power supply voltage POWER is applied to the signal generating electrode / power supply line 20, and when the image input mode is selected, the signal generating electrode is used. A high-frequency signal CHARGE is applied to the dual-purpose power line 20.

 First, a display operation of the fingerprint image input device 10 according to the present embodiment will be described. When the display mode is selected by setting the mode switching signal DI SP in Fig. 4 (B) to the H level, the fourth thin film transistor Tr 4 becomes 〇N, the fifth thin film transistor Tr 5 becomes 0 FF, and all the power sources that also serve as signal generating electrodes P〇 WER is applied to line 20. POWER is the power supply voltage for all light emitting elements 1 (R), 1 (G), and 1 (B). Usually, it is a constant DC voltage of about 5 V to 10 V.

 All output circuits of the display drive circuit 2 are electrically connected to the corresponding data lines 23.

 As shown in the timing chart of FIG. 5, first, the display image input driving circuit 3 sequentially supplies the row scanning signals ROW to the gate lines 18 and the second thin film transistors Tr 2 of all the pixels sharing the gate lines 18. Is made conductive. The timing chart of FIG. 5 shows signals before and after selecting the row scanning signals R〇W # 2 n to # 2 (n + 1).

In synchronization with this, when a video signal to be displayed is given to each of the data lines 23 # 2m to # 2 (m + 1), the video signal is stored in each capacitor C. In this way, when the video signal is stored in the capacitors C of all the pixels selected by the gate lines 18 # 2 n to # 2 (n + 1), the voltage across the capacitor C causes the third thin film transistor Tr 3 operates as an element having a constant resistance value. When the row scanning signal ROW becomes L level, the light emitting elements of these pixels According to the resistance value of the third thin film transistor Tr 3 (the resistance value corresponding to the video signal), a current is supplied from the power line 20 also serving as the signal generation electrode, and the light emitting elements 1 (R), 1 (G), and 1 Light is emitted from (B).

 By repeating the above operation for all the gate lines 18, a desired image is displayed.

 Next, an operation of inputting a fingerprint image to the image input device 10 according to the present embodiment will be described.

 Before describing the circuit operation, the capacitance formed between a finger and a pixel component will be described with reference to FIG.

 As shown in FIG. 4 (A), a capacitance C 2 is provided between the signal generating electrode and power supply line 20 and the finger F, and a capacitance C 1 is provided between the finger F and the signal detection electrode 28. It is formed. Further, a capacitance C d is also formed between the signal generating electrode power supply line 20 and the signal detecting electrode 28.

Assuming that changes the potential of the signal generating electrode combined power supply line 20 only momentarily .DELTA..nu, these three capacitances C 1, C2, Cd combined capacitance of [(1 / C 1 + 1 / C2) one ¹ + The charge amount obtained by multiplying Cd] by AV is supplied to the signal detection electrode 28. Here, the signal generation electrode / power supply line 20 is formed over almost the entire area of the input surface, but the signal detection electrode 28 is present only at one pixel. Therefore, C1 << C2, and the combined capacitance between the signal detection electrode 28 and the signal generation electrode / power source line 20 is substantially equal to (C1 + Cd).

 Based on the above considerations on capacitance, the circuit operation at the time of fingerprint image input will be described below.

 When the image input mode is selected by setting the mode switching signal DISP in Fig. 4 (B) to L level, the fourth thin film transistor Tr4 is turned off, the fifth thin film transistor Tr5 is turned on, and all the power supply lines also serve as signal generating electrodes. CHARGE is added to 20. At the same time, the seventh thin film transistor Tr7 is turned on, and all the amplifiers AMP 2m to # 2 (m + 1) of the image input detection circuit 4 have corresponding data lines 23 # 2m to # 2 (m +1).

Here, as shown in the evening timing chart of FIG. Thus, a rectangular wave is applied to all of the signal generating electrode and power lines 20. In synchronization with the scanning signals of the gate lines 18 # 2 n to # 2 (n + 1), the reset signal RST is at the H level, the eighth thin film transistor Tr8 is turned on, and the amplifiers AM P # 2m to # 2 (m + 1) output is reset.

 First, in the timing chart of FIG. 5, at the moment when the row scanning signal R2W # 2 n + 1 becomes H level, all the amplifiers AMP in the image input detection circuit 4 are turned on by the gate line 18 # 2n + l. It is electrically connected to the selected signal detection electrode 28. At the next moment, the reset signal RST goes low, and at the next moment, the high-frequency signal CHARGE rises by Δν. At this time, the output of each amplifier AMP has a voltage value proportional to the amount of charge (C 1 + Cd) AV supplied to the signal detection electrode 28 selected by the gate line 18 # 2 n + 1.

 Therefore, in order to obtain input image data, the outputs of these amplifiers AMP need only be transferred to an external circuit.

 As shown in the timing chart of FIG. 5, the read scanning signals CLM # 2 m to # 2 (m + 1) generated by the shift register circuit provided inside the image input detection circuit 4 are supplied to the amplifier AMP. This is realized by sequentially providing the ninth thin-film transistor Tr9 connected to the output terminal of the ninth thin film transistor. As a result, as shown in FIG. 5, when the gate lines # 2 n to # 2 (n + 1) are selected, the output OUT of the image input detection circuit 4 becomes the gate lines # 2n to # 2 (n + 1) This reflects the unevenness information of the finger F in the area close to.

 By repeating this operation for all the gate lines 18, the unevenness information of the finger F, that is, a fingerprint image can be obtained.

Next, a method for manufacturing the fingerprint image input device 10 according to the present embodiment will be described. 6 to 9 are cross-sectional views (shown by (A) in each drawing) showing the manufacturing steps of the main components of the pixel portion of the image input device 10 according to the first embodiment of the present invention in the order of steps. It is a top view [in each figure, it shows by (B)]. Note that the cross-sectional view (B) shows a state near the first thin-film transistor Tr1 and the third thin-film transistor Tr3 in an easily understandable manner, and is not necessarily drawn to match an actual layout. The manufacturing process is broadly divided into a pre-process for forming a thin film transistor (TFT) and a detection device, and a post-process for forming a light-emitting device using an organic EL material.

 Various thin film transistors can be employed in the manufacturing process of the thin film transistor (TFT) and the detection element as a pre-process. In this embodiment, a top gate type polycrystalline silicon (p 01 y-Si) TFT will be described as an example. First, a layer made of tungsten silicide (WS i) or another refractory metal silicide material is formed on a glass or other transparent substrate 11 by the Spack method. This refractory metal silicide material layer is patterned by photolithography, and a light-shielding layer 12 is formed on the transparent substrate 11 as shown in FIG. When the light-shielding layer 12 is formed from tungsten silicide (WSi), the thickness of the light-shielding layer 12 is set in the range of 100 to 200 nm.

Then, oxygen and silicon-containing gas (e.g., silane (S i H ₄₎₎ by a CVD method to deposit onto a substrate and then decomposed in a plasma, silicon dioxide (S i 0 ₂₎ or Ranaru Paglia layer 13 Form on one side. Noria layer 13 prevents an impurity element contained in transparent substrate 11 from diffusing into a layer above transparent substrate 11 during a subsequent process. The thickness of the barrier layer 13 is 300 to 500 nm. Next, an amorphous silicon (aSi) layer, which is a precursor of the p01ySi layer, is formed on the layer 13 by a plasma CVD method, a low pressure CVD method, or a sputtering method to a thickness of about 100 nm. Formed. The amorphous silicon (aSi) layer is irradiated with a very short pulse light of several tens of nanoseconds from the excimer laser to instantaneously melt the amorphous silicon (a-Si) layer, thereby converting the amorphous silicon (aSi) layer to polysilicon ( Reform to P 01 yS i) layer. It is known that when the irradiation energy density at this time is set to around 40 OmJ / cm ² , a po 1 yS i TFT with good characteristics can be obtained.

 The poly-Si layer is patterned by photolithography to form an island-shaped P 01 y-Si layer in the TFT forming region.

Next, a silicon dioxide (Si ₂ ) film having a thickness of about 50 nm is deposited to form a gate insulating film 16, and a tungsten silicide (WS i) having a thickness of about 20 Onm is formed on the gate insulating film 16. ) A layer is formed by sputtering, etc. The gate wiring 17 and the gate line 18 are formed by patterning a tungsten silicide (WS i) layer.

 Next, high-concentration phosphorus (P) or boron (B) is selectively introduced into the island-shaped p 0 1 y-Si layer by ion doping.

 Thereafter, the transparent substrate 11 is heated to a temperature of about 500 degrees Celsius to activate the introduced impurity elements. At this time, the concentration of the impurity element, the heating time, the temperature, and other process conditions are important, and these process conditions are determined so that an atomic contact with the wiring material to be formed later is obtained. .

 Thus, the region doped with the impurity at a high concentration becomes the source / drain region 15, and the region not doped with the impurity element becomes the channel region 14. Through the above steps, the structure shown in the cross-sectional view of FIG. 6 (FIG. 6A) and the plan view of FIG. 6B is formed. Here, in the plan view of FIG. 6B, the light-shielding layer 12 and the insulating film 16 below the TFT are not shown. Here, the gate wiring 17 serving as the gate electrode of the third thin film transistor Tr3 is extended to a region which will later serve as the lower electrode of the capacitor C.

Thereafter, a first interlayer insulating film 1-9 composed of silicon dioxide (S i 0 ₂₎ on the entire surface by plasma CVD method.

 Next, as shown in FIG. 7A, contact holes are made in the first interlayer insulating film 19 and the gate insulating film 16 to deposit chromium (Cr) and other low-resistance metal materials. The metal material is patterned to form a power supply line 20 also serving as a signal generation electrode, source electrodes 21 and 22 and a data line 23. At this time, the connection between the source region of the second thin film transistor Tr2 and the gate wiring 17 is achieved.

 Through the above steps, the previous TFT manufacturing process is completed, and the structure shown in the cross-sectional view of FIG. 7A and the plan view of FIG. 7B is formed.

In the subsequent manufacturing process, first, as shown in FIG. 8 (A), a second interlayer insulating film 24 is formed on the entire surface, and then contact is made on the source electrodes 21 and 22 by lithography and etching. Open a hole and sputter indium tin oxide (ITO) over the entire surface. Next, the ITO is patterned by lithography and etching to form a transparent electrode 25 in a region to be a lower electrode (anode) of the light emitting device 1. Here, the ITO used as the transparent electrode 25 has a sheet resistance of about 2ΟΩ / b and a thickness of about 100 nm.

 Next, a light emitting material layer 26 made of an organic EL material is formed.

 The light-emitting material layer 26 has a two-layer structure including a light-emitting layer and a hole injection / transport layer, a three-layer structure including an electron injection / transport layer, or a structure in which a thin insulating film is disposed at the interface with a metal electrode Can be adopted. That is, in FIG. 8A, the light-emitting material layer 26 is simply shown as the light-emitting material layer 26, but the light-emitting material layer 26 is an organic film that can be formed by a multilayer film.

 As a method for manufacturing the light emitting material layer 26, a spin coating method, a vacuum evaporation method, or an ink jet printing method can be used. Depending on each manufacturing method, a polymer or low molecular organic EL material is used. Selection, base structure, method of manufacturing upper electrode, and other manufacturing conditions are determined.

 In this embodiment, the light-emitting material layer 26 has a two-layer structure of a light-emitting layer and a hole transport layer. Examples of the material of the hole injection / transport layer include a triarylamine derivative and an oxaziazole derivative. Alternatively, a porphyrin derivative can be selected. As a material of the light emitting layer, for example, a metal complex of 8-hydroxyquinoline and its derivative, a tetrafu: nilbutadiene derivative or a distyraryl derivative can be selected. Each of the light emitting layer and the hole transport layer is formed by laminating each to a thickness of about 50 nm by a vacuum evaporation method.

 In FIG. 8A, the light-emitting material layer 26 is patterned so as to substantially cover the transparent electrode 25. However, since the light-emitting material layer 26 is a layer made of an insulating material, However, patterning is not necessarily required, and the transparent substrate 11 may be formed so as to cover the entire surface. However, when the image input device 10 according to the present embodiment is applied to a color display, at least three types of light emitting material layers and their separation are necessary, so that the patterning of the light emitting material layer 26 is required. is necessary.

Next, as a cathode of the light-emitting element 1, aluminum-lithium alloy A1Li or another material having a low work function is vacuum-deposited to a thickness of about 200 nm through a metal shadow mask to emit light. A GND line 27 serving as a cathode of the element 1 is formed. At this time, a signal detection electrode 28 is simultaneously formed on the first thin film transistor Tr1 side. Is done.

 As a material used for the cathode of the light emitting element 1, a material having a high work function and a high light reflectance is more preferable.

Finally, as shown in Fig. 9 (A), a plasma CVD method and other film-forming methods are used to deposit Si ON, Si N x, Si _{2 and} other inorganic materials to a thickness of about 1 m on the entire surface. To form a protective layer 29. In addition to these inorganic materials, the protective layer 29 can be formed using an organic material having low oxygen permeability such as an ethylene 'vinyl alcohol' copolymer or a silane-modified fluororesin.

 As described above, according to the image input device 10 according to the present embodiment, approximately 100% of the light emitted from the light emitting element 1 can be used for display. Therefore, the fingerprint image according to the present embodiment formed using a glass or other transparent substrate 11 is compared with a conventional multi-layer display image input device configured to be stacked on a liquid crystal display or other display device. The input device 10 has a high light use efficiency, and as a result, an effect of reducing power consumption can be obtained.

 Further, as described above, in the image input device 10 according to the present embodiment, a part of the wiring is shared between components necessary for inputting a fingerprint image and components required for image display. The area occupied by wiring is reduced. As a result, the area of the light emitting element 1 can be increased, and a bright display can be realized. Further, the thickness of the image input device 10 according to the present embodiment is almost determined by the thickness of the substrate. Therefore, when a glass substrate used in a normal TFT process is used, the thickness is about 0.7 mm. In other words, the thickness of the conventional multi-layer display / image input device shown in FIG. 17 is much thinner than the thickness of about 2.4 mm. This is a great advantage when the image input device according to the present embodiment is built in a portable device or the like.

Also, in the conventional stacked display / image input device shown in Fig. 17, when a TFT-type liquid crystal display is adopted, a transparent substrate on which a large number of TFTs are arranged is also required for a fingerprint image input device. Therefore, a total of two substrates that have undergone the TFT manufacturing process are required. On the other hand, in the image input device 10 according to the present embodiment, only one substrate having undergone the TFT manufacturing process is sufficient. Therefore, according to the image input device 10 according to the present embodiment, The manufacturing process and manufacturing time for TFTs can be reduced, and the manufacturing cost can be reduced.

(Second embodiment)

 In the first embodiment described above, the power supply line was used as the signal generating electrode. However, as the wiring formed on almost the entire surface of the image input device, in addition to the power supply line, the 0 line 27 and the gate line 18 were used. There is. In the second embodiment described below, a GND line is also used as a signal generation electrode instead of a power supply line.

 FIG. 10A is a cross-sectional view illustrating a capacitance formed in the image input device according to the second embodiment of the present invention.

 As shown in FIG. 10A, in this embodiment, a capacitance C 1 is provided between the finger F and the signal detection electrode 28, and a capacitance C 1 is provided between the finger F and the signal generation electrode / GND line 27a. Represents a capacitance C 2, and a capacitance C d is formed between the signal generating electrode and GND line 27 and the signal detecting electrode 28.

 FIG. 10B is a circuit diagram illustrating a circuit configuration of the image input device according to the second embodiment of the present invention.

 The difference from the circuit configuration of the first embodiment is that the power supply voltage 'POWER is always applied to the power supply line 20a, and the display mode or the image input mode is applied to the signal generation electrode / GND line 27a. The only difference is that either the ground voltage GND or the high-frequency signal CHA RGE is applied, and the other circuit configuration is the same as the circuit configuration of the first embodiment.

 Therefore, the operation of the image input device according to the present embodiment is substantially the same as that of the first embodiment. In the description of the operation of the image input device according to the first embodiment, the signal generation electrode / power supply line 20 is connected to the signal generation electrode. It can be read as a combined GND line 27a.

(Third embodiment)

 In the above-described first embodiment, the power supply line is used as the signal generating electrode, and in the second embodiment, the GND line is used as the signal generating electrode. In the third embodiment, the signal generating electrode is used as the signal generating electrode. Use gate lines.

FIG. 11A is a cross-sectional view illustrating a capacitance formed in the image input device according to the third embodiment of the present invention. As shown in FIG. 11A, in this embodiment, a capacitance C 1 is provided between the finger F and the signal detection electrode 28, and a capacitance C 1 is provided between the finger F and the specific gate line 18A. The capacitance C2 is formed between the specific gate line 18A and the signal detection electrode 28, respectively.

 FIG. 11B is a circuit diagram illustrating a circuit configuration of the image input device according to the present embodiment. The circuit in the image input device according to the present embodiment differs from the first embodiment in that a constant potential is always applied to the power supply line 20a and the GND line 27. This embodiment is characterized by the waveform of the row scanning signal applied to the gate line 18A. As shown in the timing chart of FIG. 12, the gate lines adjacent to each other have a pulse width of 1Z. A scanning signal ROW overlapping by two is applied.

 FIG. 12 is a timing chart for explaining the operation of the image input device according to the third embodiment of the present invention. Hereinafter, the operation of the image input device according to the third embodiment will be described with reference to FIG.

 When the gate line 18 # 2 n is at the H level, all the amplifiers AMP of the image input detection circuit 4 are electrically connected to the signal detection electrode 28 selected by the gate line 18 # 2 n. At the moment when the next gate line 18A # 2 n + 1 goes to the H level, the capacitance C 2 between the gate line 18A # 2n + l and the finger F, the finger F and the signal detection electrode 28 Signal detected by the gate line 18 # 2 n via the combined capacitance of the capacitance C 1 between the gate line 18 A # 2 n + 1 and the capacitance Cd between the signal detection electrode 28 Charge is applied to the electrode 28 from the gate line 18A # 2 n + 1.

 As in the first and second embodiments, since C1 << C2, the output of each amplifier AMP has a voltage value proportional to the charge amount (C1 + Cd) AV. Accordingly, by transferring the outputs of these amplifiers AMP to an external circuit in the same manner as in the above-described embodiment, the unevenness information of the finger F in the region close to the gate line 18 # 2n can be obtained. By repeating this operation for all the gate lines 18, the unevenness information of the finger F, that is, a fingerprint image is obtained.

In this embodiment, the high-frequency signal CHARGE is omitted, and the switching transistors (the fourth thin film transistor Tr 4 and the fifth thin film transistor Tr 5) for selecting between the CHAR GE and the constant potential are omitted. Gate line 1 The scanning signals ROW applied to the signal 8 overlap each other with a pulse width of 1 Z2, and the voltage corresponding to the combined capacitance of the signal detection electrodes 28 is read at the switching timing. Therefore, according to the image input device according to the present embodiment, a fingerprint image input device with a display function can be realized with a simpler configuration than the image input device according to the first embodiment.

(Fourth embodiment)

 In the first to third embodiments described so far, the light emitting element 1 is configured to emit light in a direction transmitting the transparent substrate 11. Therefore, the surface on which the image is displayed is the surface opposite to the surface on which the fingerprint is input. As described later, there are cases where it is desired to realize image display and fingerprint image input on the same surface depending on the application form. Such a device can be realized by forming the top emission type element by exchanging the arrangement of the transparent electrode and the metal electrode sandwiching the organic EL material.

 FIG. 13 is a plan view (FIG. 13 (A)) and a cross-sectional view (FIG. 13 (B)) of an image input device according to a fourth embodiment of the present invention. Here, components having the same functions as those of the first embodiment are denoted by the same reference numerals.

 In FIG. 13 (B), the light emitting element 1 formed on the insulating substrate 11a is formed by laminating a metal electrode 30, an organic EL material layer 26, and a transparent electrode 25 in this order. Here, since light is emitted toward the transparent electrode 25, the insulating substrate 11a does not need to be transparent. ·

 Further, the transparent electrode 25 also serves as a GND line. Therefore, the circuit configuration is the same as that of the second embodiment.

 (Fifth embodiment)

 In the embodiments described so far, the light emitting element 1 is configured to be connected to the GND line side, but may be connected to the power supply line side. In the fifth embodiment, similarly to the fourth embodiment, a configuration in which the image display surface and the fingerprint image input surface are matched is realized by connecting the light emitting element to the power supply line side. are doing.

FIGS. 14A, 14B, and 14C are a plan view, a circuit diagram, and a cross-sectional view, respectively, showing a main part of an image input device according to a fifth embodiment of the present invention. Here, the same components as those of the fourth embodiment are denoted by the same reference numerals. As shown in FIG. 14, in the fifth embodiment, the source of the third thin film transistor Tr3 is connected to the GND line 27b also serving as a signal generation electrode. Then, in a region where the signal generating electrode / common GND line 27b and the gate wiring 17 overlap, a capacitor C is formed using the first interlayer insulating film 19 as a dielectric layer.

 A metal electrode 30 serving as a cathode is formed below the light emitting material layer 26, and a transparent electrode 25 serving as an anode is formed above the light emitting material layer 26. The transparent electrode 25 extends in the row direction to form a power line 20a. That is, in the present embodiment, the GND line 27 b extends in the column direction, and the power supply line 20 a extends in the row direction. The operation of the image input device according to the present embodiment is the same as that of the second embodiment. In the present embodiment, the GND line 27b also serves as a signal generating electrode, but the power supply line 20a (transparent electrode 25) may be configured to also serve as a signal generating electrode. Also, a constant potential is applied to the power supply line 20a and the GND line 27b regardless of the mode switching. In the image input mode, as shown in FIG. The fingerprint signals may be obtained by making the scan signals applied to the scans overlap each other by a pulse width of 1 Z2. .,

 In addition, even when the light emitting element 1 is connected to the power supply line side, the display light is emitted to the back side of the substrate 11a using the upper electrode 25 as a metal electrode and the lower electrode 30 as a transparent electrode. It is also possible. In this case, a transparent substrate is used as the substrate 11a.

 (Sixth embodiment)

 The image input device having a built-in display function according to the first to fifth embodiments described above is thin and has high light use efficiency, and thus is advantageous for mounting on a portable device such as a mobile phone. FIG. 15 is a perspective view of a mobile phone 31 according to a sixth embodiment of the present invention. The mobile phone 31 includes one of the image input devices according to the first to fifth embodiments. One is installed.

As shown in FIG. 15, the mobile phone 31 according to the present embodiment includes a first housing 35, a second housing 36, a first housing 35, and a second housing. And a hinge mechanism 37 that rotatably connects the end portions 36 with each other at their ends. In the first housing 35, for example, the image input device 10 according to the first embodiment includes the image input surface 32 of the fingerprint in the state where the mobile phone 31 is folded, and the display surface 3 3 Is implemented so that is inside.

 The mobile phone 31 according to the present embodiment can be used as follows.

 For example, when a mobile phone 31 is folded and a finger is brought into close contact with the image input surface 32 to input a fingerprint image, and the mobile phone 31 is authenticated as a valid owner, the mobile phone 31 2 1 can be made available.

 Alternatively, when various services are provided through the mobile phone 31, the fingerprint can be confirmed through the mobile phone 31 when the service provider authenticates the individual when charging. .

 In addition, fingerprints can be used as various payment methods. Further, in the mobile phone 31, since the image input surface 32 and the display surface 33 are separately provided, there is no need to bring a finger into close contact with the display surface 33. Therefore, it is possible to avoid the problem that the image quality of display is deteriorated due to the remaining fingerprints attached to the display surface 33.

 (Seventh embodiment)

 FIG. 16 is a perspective view of a mobile phone 31A according to a seventh embodiment of the present invention. The mobile phone 31A has image input devices according to the first to fifth embodiments. Either one is installed.

 The mobile phone 31A according to the present embodiment includes a first housing 35, a second housing 36, and a first housing, similarly to the mobile phone 31 according to the sixth embodiment. And a hinge mechanism 37 for rotatably connecting the end 35 and the second housing 36 to each other at their ends.

 In the mobile phone 31A according to the seventh embodiment, a fingerprint image input device with a display function in which the fingerprint image display surface and the fingerprint image input surface match each other is mounted. Specifically, as shown in FIG. 16, the fingerprint image is placed on the first housing 35 so that the image input surface and display surface 34 is in the folded state of the mobile phone 31A. Input device is mounted.

In this way, when the fingerprint image display surface and the fingerprint image input surface match, the operation of superimposing the actual finger on the finger figure displayed on the image input surface and display surface 34 is performed by the operation. The fingerprint input operation can be performed reliably. Therefore, the stability of fingerprint image input is increased, and the accuracy of personal authentication can be improved.

 In the present embodiment, the image input / shared display surface 34 is arranged such that the image input / shared display surface 34 is inside when the mobile phone 31A is folded. However, it is also possible to arrange the mobile phone 31A so as to face the outside of the mobile phone 31A.

 Note that such a function can be realized by switching to the image mode with the actual finger superimposed on the displayed finger figure, or by alternately switching the display mode and the image input mode at high speed. Can be.

 In the embodiments described above, appropriate changes can be made.

 For example, in the first embodiment, an example of realizing a color display of 200 ppi (7.87 pi Xe 1 / mm) and a fingerprint image input of 400 dpi (15.75 dots / mm) has been described. The resolution and pixel layout for display and image input are not limited to these examples, and various combinations of resolutions can be realized by changing the pixel layout.

 Further, in the above embodiments, the example of the top gate type po 1 y-Si TFT has been described. However, the circuit can be configured using the bottom gate type p 0 1 y-Si TFT. .

 Alternatively, an a-Si TFT, which is widely used in liquid crystal displays, can be used. However, since the carrier mobility in a—Si is about 1Z100 of po 1 y—Si, the resistance must be sufficiently low especially when used as a TFT for supplying current to a light emitting element. Will be needed. For example, by setting the width of the TFT large or reducing the thickness of the gate insulating film, the resistance of the a-Si TFT can be reduced.

 Further, in the above-described embodiment, the configuration in which the display driving circuit 2 and the image input detection circuit 4 are formed on the transparent substrate 11 by using a polySi TFT has been described. Is not limited to this.

For example, TAB (Tape Automated Bonding) connection and COG (Chi On G 1 ass) connection As generally practiced in, a similar function can be realized by an integrated circuit formed of a crystal semiconductor, and this integrated circuit can be fixed on the transparent substrate 11 and electrically connected.

 Further, in the above-described embodiment, the configuration in which the light-emitting materials of three colors (R, G, and B) are arranged in a square shape has been described, but a configuration in which the respective colors are arranged in a stripe shape may be employed. Also, a color display can be realized by combining a color filter and a white light-emitting material, or by combining a blue light-emitting material and a color conversion material. Industrial applicability

 As described above, according to the fingerprint image input device of the present invention, almost 100% of the light emitted from the light emitting element can be used for display, so that the light use efficiency is high, and as a result, However, power consumption can be kept low.

 Furthermore, by sharing a part of the wiring required for the components required for fingerprint image input and the components required for image display, the area occupied by the wiring can be reduced. The area of the light-emitting element can be increased, and a bright display can be realized.

 Further, the thickness of the fingerprint image input device according to the present invention is almost determined by the thickness of the substrate, and when a glass substrate used in a normal TFT process is used as the substrate, the thickness may be about 0.7 mm. It is possible, and a significant reduction in thickness can be achieved. This thinning is a great advantage when the fingerprint image input device according to the present invention is incorporated in a portable device or the like.

 In addition, when a TFT display capable of displaying high-quality images is adopted, according to the fingerprint image input device of the present invention, it is sufficient to perform the TFT manufacturing process on only one substrate. Costs can be kept low.

Claims

The scope of the claims

1. The substrate and

 A plurality of signal detection electrodes arranged on one plane of the substrate,

 A plurality of light emitting elements arranged on the same plane as the plane on which the signal detection electrodes are arranged;

 With the '

 By detecting a capacitance formed between the signal detection electrode and the finger, a fingerprint image input mode for obtaining a fingerprint image, and causing the light emitting element to emit light in accordance with the capacitance, A fingerprint image input device that can be switched to a fingerprint image display mode for displaying fingerprint images.

2. The fingerprint image input device according to claim 1, wherein the fingerprint image input device is a protective layer that can be brought into contact with a finger, the protective layer covering the signal detection electrode and the light emitting element.

3. When inputting the fingerprint image, a part of a wiring for driving the light emitting element is used as a signal wiring for detecting the capacitance. 3. The fingerprint image input device according to 2.

4. The fingerprint image input device according to claim 1, wherein the light emitting elements are arranged in a matrix in a one-to-one correspondence with the signal detection electrodes.

5. a plurality of scanning signal wirings arranged on the substrate;

 A plurality of data signal wirings arranged on the substrate at right angles to the scanning signal wirings;

A first switch element connected to the scanning signal wiring and the data signal wiring, and connected to the signal detection electrode; A second switch element connected to the scanning signal wiring and the data signal wiring, a current control element connected to the second switch element,

 With

 The fingerprint image input device according to any one of claims 1 to 4, wherein the light emitting element is connected to the current control element in series.

6. power supply wiring arranged on the board;

 Ground wiring arranged on the substrate,

 The light emitting element and the current control element connected in series are connected to the power supply wiring on one side, and are connected to the ground wiring on the other side. The fingerprint image input device described in the above.

7. The apparatus further comprises a signal generating electrode to which either the power supply wiring or the ground wiring is connected when the fingerprint image is input, wherein a high-frequency signal is applied to the signal generating electrode. 7. The fingerprint image input device according to claim 6, wherein:

8. When inputting the fingerprint image, a scanning signal overlapping with another scanning signal wiring adjacent to the scanning signal wiring for a predetermined time is sequentially applied to each of the scanning signal wirings. The fingerprint image input device according to claim 5.

9. A mode switching switch element,

 A display driving circuit to which one end of the data signal wiring is connected via the mode switching switch element;

 An image input detection circuit to which the other end of the data signal wiring is connected via the mode switching switch element;

 A display image input drive circuit to which one end of the scanning signal wiring is connected,

The fingerprint image input device according to any one of claims 5 to 8, further comprising:

10. The display drive circuit, the image input detection circuit, and the display image input drive circuit are formed of a thin film transistor formed on the substrate. Fingerprint image input device.

11. The fingerprint image input device according to claim 1, wherein the light emitting element is formed using an organic electroluminescent material.

1 2. The substrate is a transparent substrate, the lower electrode of the light emitting element is formed of a transparent conductive film, and light emitted from the light emitting element is emitted from the back surface of the substrate. 11. The fingerprint image input device according to claim 11, wherein:

13. The fingerprint image according to claim 11, wherein an upper electrode of the light emitting device is formed of a transparent conductive film, and light emitted from the light emitting device is emitted above the substrate. Input device.

14. The fingerprint image input device according to claim 12, wherein the lower electrode or the electrode opposite to the upper electrode is formed of a metal material having a high light reflectance. 15.

1 5. a first housing;

 A second housing that is foldably connected to the first housing via a hinge mechanism,

 A fingerprint image input device according to any one of claims 1 to 14,

 Consisting of

The fingerprint image input device may be configured such that when the first housing and the second housing are folded together, the fingerprint image input surface of the substrate is the first housing or the second housing. It is incorporated in one of the first housing and the second housing so that either one of the outside and the inside of the body faces and the fingerprint image display surface of the substrate faces the other. machine.

1 6. a first housing;

 A second housing that is foldably connected to the first housing via a hinge mechanism,

 A fingerprint image input device according to any one of claims 1 to 14,

 Consisting of

 The fingerprint image input device may be configured such that when the first housing and the second housing are folded together, the fingerprint image input surface and the fingerprint image display surface of the substrate are the same as the first housing. Or a device incorporated in one of the first housing and the second housing so as to face either the outside or the inside of the second housing.

17. The device according to claim 15, wherein the device is a mobile phone device.

1 8. a process of touching a finger on the one plane of the fingerprint image input device in which a plurality of signal detection electrodes are arranged on one plane of the substrate;

 Detecting a capacitance formed between the signal detection electrode and the finger to obtain a fingerprint image;

 A fingerprint image input method comprising:

1 9. The fingerprint image input device further includes a plurality of light emitting elements arranged on the same plane as the plane on which the signal detection electrodes are arranged, and the light emitting elements emit light according to the capacitance. 19. The fingerprint image input method according to claim 18, further comprising: displaying the fingerprint image.