JP2010286875A - Electro-optical device, method for driving the same, and electronic equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To achieve both reading of an image from an original and the input of information on the basis of the indication of a displayed in-image position by an indicator in an electro-optical device having an optical sensor and a light source. <P>SOLUTION: The electro-optical device 10 is provided with: a transparent first substrate 1; an optical sensor 5 formed on the first substrate 1 for detecting the light quantity of incident rays of light; a second substrate 4 sandwiched between the optical sensor 5 and the first substrate 1; and a light emitting element 7 sandwiched between the second substrate 4 and the optical sensor 5 for emitting the rays of light to the first substrate 1. In the case of reading an image from the original, the original and the first substrate 1 are opposed to each other, and a portion of the emitted rays of light of the light emitting element 7 is reflected, and made incident on an optical sensor 5. In the case of inputting a position by the indicator, the first substrate 1 and the pen 30 are brought into contact with each other or made to approach each other, and external rays of light made incident on the optical sensor 5 in the vicinity of the top end 31 of the pen 30 are intercepted. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an electro-optical device including an optical sensor and a light source.

  As an electro-optical device including an optical sensor and a light source, the light source integrated image sensor described in Patent Document 1 can be exemplified. In this image sensor, a light source (EL element) illuminates an original and an optical sensor (light receiving element) receives reflected light from the original, thereby reading an image from the original. Patent Document 2 discloses a portable terminal device with a built-in image sensor that can read characters from a document and input characters. As another apparatus for inputting characters, there is an apparatus for practicing character writing described in Patent Document 3. The user of this apparatus inputs characters by displaying characters on a liquid crystal tablet capable of displaying images and tracing the characters with a pen.

JP-A-5-191564 (FIG. 1) JP-A-9-65028 (FIG. 10) Japanese Patent Laying-Open No. 2007-72086 (FIG. 1)

In the devices described in Patent Documents 1 and 2, it is possible to read an image from a document, but it is impossible to input information by pointing the position in the displayed image with an indicator such as a finger or a pen. On the other hand, the apparatus described in Patent Document 3 can input information by pointing a position in a displayed image with a pen, but cannot read an image from a document.
Therefore, the present invention enables both reading of an image from a document and inputting information by pointing a position in the displayed image with an indicator in an electro-optical device including an optical sensor and a light source. This is the solution issue.

In order to solve this problem, the present invention provides a transparent first substrate, an optical sensor that is formed on the first substrate and receives light from the first substrate and detects a received light amount, and the light An electro-optic comprising a second substrate that sandwiches a sensor with the first substrate, and a light emitting element (light source) that is sandwiched between the second substrate and the optical sensor and emits light toward the first substrate. Providing equipment. Note that “light emission toward the first substrate” includes emitting light only toward the first substrate and emitting light toward all directions.
According to this electro-optical device, since the first substrate is transparent, the light from the light emitting element is transmitted through the first substrate, and the transmitted light includes an external part such as a finger, a pen, or a document. The light (reflected light) reflected by the object can pass through the first substrate and enter the optical sensor. Therefore, according to this electro-optical device, an image is displayed by controlling the luminance of the light emitting element, and a position in the image indicated by an external indicator (finger, pen, etc.) is detected. And reading an image from an external document. That is, according to this electro-optical device, both reading of an image from a document and information input by pointing the position in the displayed image with an indicator are possible.

  The electro-optical device may include a light shielding layer that blocks light between the light emitting element and the optical sensor. Even if a light-emitting element that emits light directed in all directions is used in this electro-optical device, the light emission of the light-emitting element does not directly enter the optical sensor, so the accuracy of image reading and position detection is improved. There is an advantage that it does not decrease.

  In each of the electro-optical devices described above, the second substrate may be transparent. This electro-optical device is a so-called dual emission type light emitting device, and can display an image on both the first substrate and the second substrate. In the case of the electro-optical device including the light shielding layer, the brightness of the image displayed on the first substrate depends on the amount of light shielded by the light shielding layer, but the brightness of the image displayed on the second substrate is It does not depend on the amount of light blocked.

  Each of the electro-optical devices may include a plurality of the light sensors and the light emitting elements, and each of the plurality of light sensors may not overlap with any of the plurality of light emitting elements in a plan view. In this electro-optical device, since there are a plurality of light emitting elements, the image display resolution is increased. In addition, since the electro-optical device includes a plurality of optical sensors, the accuracy of image reading and position detection is increased. Further, according to this electro-optical device, the light emitting element and the optical sensor do not overlap each other, so that the amount of light blocked by the light shielding layer among the light from the light emitting element can be suppressed. Therefore, this electro-optical device has an advantage that the image displayed on the first substrate is not so dark. As an arrangement in which the light emitting element and the optical sensor do not overlap each other, the arrangement shown in FIG. 1 can be exemplified. By adopting this arrangement, it is possible to suppress variations in image display resolution, image reading accuracy, and position detection accuracy on a plane parallel to the first substrate.

Further, the present invention provides a method for driving the electro-optical device, in which an image is read from the original with the surface of the first substrate opposite to the surface on the second substrate facing the original. When the plurality of light emitting elements emit light with a common luminance and an image is displayed, the light emission of the plurality of light emitting elements is individually controlled based on the displayed image. I will provide a. According to this method, the electro-optical device is used for both reading and displaying an image, that is, both reading an image from a document and inputting information by pointing a position in the displayed image with an indicator. Can be used.
In addition, the present invention provides an electronic apparatus including each of the electro-optical devices described above. In addition, the present invention includes an electro-optical device including a plurality of optical sensors and light emitting elements, and emits the plurality of light emitting elements with a common luminance, so that the surface of the first substrate on the second substrate side is Provided is an electronic device that reads an image from a document facing the opposite surface, recognizes characters from the read image, and converts the recognized characters into sound. According to another aspect of the invention, there is provided an electronic apparatus that includes an electro-optical device including a plurality of optical sensors and a plurality of light-emitting elements, and is used by being placed on a placement surface, the second substrate side of the first substrate. When reading an image from the original with the surface opposite to the original facing the original, the first substrate is sandwiched between the placement surface and the second substrate to display an image. The second substrate may be sandwiched between the placement surface and the first substrate. According to this electronic apparatus, the above two cases can be dealt with by inverting the top and bottom of the electro-optical device.

1 is a plan view of an electro-optical device 100 according to an embodiment of the present invention. It is the sectional view on the AA line of FIG. 2 is a diagram illustrating an electrical configuration of the electro-optical device 100. FIG. 3 is a circuit diagram showing an electrical configuration of a light emitting circuit E in the electro-optical device 100. FIG. 3 is a circuit diagram for explaining a light emission reset operation of the light emitting circuit E. FIG. 6 is a circuit diagram for explaining a writing operation of the light emitting circuit E. FIG. 3 is a circuit diagram for explaining a light emitting operation of a light emitting circuit E. FIG. 3 is a circuit diagram showing an electrical configuration of a sensing circuit S in the electro-optical device 100. FIG. FIG. 6 is a circuit diagram for explaining a detection reset operation of the sensing circuit S. 6 is a circuit diagram for explaining an exposure operation of the sensing circuit S. FIG. FIG. 6 is a circuit diagram for explaining a reading operation of the sensing circuit S. 3 is a timing chart for explaining the operation of the electro-optical device 100. FIG. FIG. 4 is a diagram illustrating an example of a document whose character is read by the electro-optical device. 6 is a diagram for describing a first operation of a control circuit 15 in the electro-optical device 100. FIG. 7 is a diagram for explaining a second operation of the control circuit 15. FIG. 6 is a diagram illustrating a display example of the electro-optical device 100. FIG. 6 is a diagram showing another display example of the electro-optical device 100. FIG. 6 is a perspective view illustrating an application example of the electro-optical device 100. FIG. 11 is a perspective view illustrating another application example of the electro-optical device 100. FIG. 12 is a perspective view illustrating still another application example of the electro-optical device 100. FIG.

  An embodiment of the present invention will be described with reference to the drawings. However, in each drawing, the ratio of the dimension of each part is appropriately different from the actual one. In addition, the present invention is not limited to one embodiment described below, and various modifications obtained by modifying the embodiments and application examples obtained by applying these may be included in the technical scope. . In addition, the same code | symbol is attached | subjected to the common part in each figure.

  FIG. 1 is a plan view of an electro-optical device 100 according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view taken along line AA of FIG. The electro-optical device 100 is used for a device that can read out characters written on a manuscript and input a stroke, and is formed of a transparent material such as glass as shown in FIG. The circuit layer 2 and the light source layer 3 are disposed between the first substrate 1, the circuit layer 2 formed on the first substrate 1, the light source layer 3 formed on the circuit layer 2, and the first substrate 1. And a second substrate 4 sandwiched therebetween. The second substrate 4 is made of a transparent material such as glass.

  The circuit layer 2 includes a plurality of optical sensors 5 and a plurality of light shielding layers 6. The optical sensor 5 is a sensor that receives light from the first substrate 1 and detects the amount of received light. Specifically, the optical sensor 5 is a photodiode that generates a photocurrent corresponding to the amount of received light. The light blocking layer 6 is a layer that blocks light, has a one-to-one correspondence with the light sensor 5, and is disposed on the light source layer 3 side of the corresponding light sensor 5. On the other hand, the light source layer 3 includes a plurality of light emitting elements 7. The light emitting element 7 is an element that emits light. Specifically, the light emitting element 7 is an organic EL element that emits light with a luminance corresponding to a driving current.

  As shown in FIG. 1, when viewed from a direction perpendicular to the first substrate 1, the light emitting elements 7 and the optical sensors 5 are arranged in a staggered pattern. Specifically, in plan view, the plurality of light emitting elements 7 are arranged in a matrix of m rows and n columns, and the plurality of photosensors 5 are arranged in a matrix of m-1 rows and n-1 columns. One optical sensor 5 overlaps the center point of any four adjacent light emitting elements 7, and each optical sensor 5 overlaps one of the center points. Further, the optical sensor 5 is covered with a corresponding light shielding layer 6 in a direction perpendicular to the first substrate 1.

  FIG. 3 is a diagram illustrating an electrical configuration of the electro-optical device 100. As shown in the figure, the electro-optical device 100 includes an m-row n-column light-emitting circuit E, an m-1 row n-1 column sensing circuit S, and m light-emission control lines each extending in the row direction. YA, YB, YC, n data lines X extending in the column direction, m−1 detection control lines ZA, ZB each extending in the row direction, and n−1 extending in the column direction. Book sense line W.

  Each light emitting circuit E includes a light emitting element 7, and each sensing circuit S includes an optical sensor 5. The light emission circuit E in the i-th row and the j-th column is electrically connected to the light-emission control lines YAi, YBi, YCi in the i-th row and the data line Xj in the j-th column. However, i is a natural number of m or less, and j is a natural number of n or less. On the other hand, to the p-th row and q-th column sensing circuit S, the p-th row detection control lines ZAp and ZBp and the q-th column sense line Wq are electrically connected. However, p is a natural number of m−1 or less, and q is a natural number of n−1 or less.

  The electro-optical device 100 includes a light emission control line driving circuit 11, a data line driving circuit 12, a detection control line driving circuit 13, a reading circuit 14, and a control circuit 15 that controls these circuits. The control circuit 15 is supplied with gradation data for designating the luminance of the light emitting element 7 in m rows and n columns from an external device. Further, the control circuit 15 supplies image data indicating the detection result of the sensing circuit S of m−1 rows and n−1 columns to an external device. Note that one or more of the circuits 11 to 15 may be provided outside the electro-optical device 100.

  The light emission control line drive circuit 11 sequentially selects the light emission circuits E line by line by outputting write signals WRT1 to WRTm to the light emission control lines YA1 to YAm. The write signals WRT1 to WRTm are signals obtained by shifting a pulse that is at an active level by 1H for another fixed period (horizontal scanning period = 1H) in a fixed period (vertical scanning period = 1V). The light emission control line drive circuit 11 sequentially resets the light emission circuit E line by line by outputting reset signals ERST1 to ERSTm to the light emission control lines YB1 to YBm, whereas the light emission control lines YC1 to YCm emit light signals EL1 to EL1. By supplying ELm, the supply / cutoff of the drive current to the light emitting element 7 is controlled.

  The data line driving circuit 12 outputs data signals D1 to Dn to the data lines X1 to Xn, thereby writing a voltage to the light emitting circuit E in the selected row in the light emission control line driving circuit 11. The written voltage is held, and the light emitting element 7 is driven with a current (drive current) corresponding to the held voltage. The levels of the data signals D1 to Dn vary depending on the image to be displayed.

  The detection control line driving circuit 13 sequentially selects the sensing circuits S row by row by supplying selection signals SEL1 to SELm-1 to the detection control lines ZA1 to ZAm-1. The selection signals SEL1 to SELm-1 are signals obtained by shifting the write signals WRT1 to WRTm-1 by a certain time. The detection control line driving circuit 13 sequentially resets the sensing circuit S line by line by supplying reset signals SRST1 to SRSTm-1 to the detection control lines ZB1 to ZBm-1.

  The readout circuit 14 reads the detection results from these sensing circuits S by receiving the detection signals output from the sensing circuits S in the row selected by the detection control line driving circuit 13 to the sense lines W1 to Wn-1. . The detection signal is a signal indicating the detection result, and the sensing circuit S outputs a signal corresponding to the photocurrent generated in the optical sensor 5 as the detection signal. Further, the readout circuit 14 supplies the control circuit 15 with image signals indicating detection results of the sensing circuit S of m−1 rows and n−1 columns, that is, (m−1) × (n−1) detection results. .

  FIG. 4 is a circuit diagram showing an electrical configuration of the light emitting circuit E. As shown in FIG. The light-emitting circuit E shown in this figure is of the i-th row and j-th column and includes a light-emitting element 7, a drive transistor Tdr, a transistor Ta, a transistor Tb, and a capacitor C1. The light emitting element 7 is interposed between a power supply line to which a fixed power supply potential Vel is supplied and a ground line, and a drive transistor Tdr is inserted in a path from the power supply line to the light emitting element 7. A transistor Tel is interposed between the drive transistor Tdr and the light emitting element 7. The capacitive element C1 includes a first electrode L1 and a second electrode L2.

  The drive transistor Tdr generates a drive current according to the voltage Vgs between the source and the gate, the source is the power supply line and the first electrode L1 of the capacitor C1, and the gate is the second of the capacitor C1. The drain of the electrode L2 is connected to the transistor Tel. The capacitive element C1 is for holding the written voltage, and this holding voltage becomes the voltage Vgs.

  A transistor Tb is interposed between the gate and drain of the driving transistor Tdr. The transistor Tb functions as a switching element, and a reset control line YBi is connected to the gate of the transistor Tb. That is, only when the reset signal ERSTi is at the active level, the transistor Tb is turned on, the drive transistor Tdr is diode-connected, and the holding voltage of the capacitive element C1 is reset.

  A transistor Ta is interposed between the second electrode L2 of the capacitive element C1 and the data line Xj. The transistor Ta functions as a switching element, and its gate is connected to the light emission control line YAi. That is, only during the period when the write signal GWRTi is at the active level, the transistor Ta is turned on and the voltage is written to the capacitor C1.

  The transistor Tel functions as a switching element, and its gate is connected to the light emission control line YCi. Therefore, the transistor Tel is turned on only during the period in which the light emission signal ELi is at the active level, and the drive current is supplied from the drive transistor Tdr to the light emitting element 7.

  In the light emitting circuit E, the light emission reset operation, the writing operation, and the light emission operation are cyclically performed at a constant cycle. This period coincides with a length of 1V. In the light emission reset period in which the light emission reset operation is performed, as shown in FIG. 5, the transistor Ta is kept off, the transistor Tb is kept on, and the transistor Tel is kept off. Therefore, the driving transistor Tdr is diode-connected, and the holding voltage of the capacitive element C1 is reset.

  In the writing period in which the writing operation is performed, as shown in FIG. 6, the transistor Ta is kept on, the transistor Tb is kept off, and the transistor Tel is kept off. Therefore, a differential voltage between the power supply potential Vel and the potential of the data line Xj is written into the capacitor C1. Since the power supply potential Vel is fixed, this voltage is determined by the potential of the data line Xj, that is, the level of the data signal Dj.

  In the light emission period in which the light emission operation is performed, as shown in FIG. 7, the transistor Ta is kept off, the transistor Tb is kept off, and the transistor Tel is kept on. Therefore, the light emitting element 7 is driven with a driving current corresponding to the holding voltage of the capacitive element C1, and emits light with a luminance corresponding to the driving current.

  FIG. 8 is a circuit diagram showing an electrical configuration of the sensing circuit S. The sensing circuit S shown in this figure is of the p-th row and the q-th column, and includes an optical sensor 5, transistors Tc and Td, an amplifying transistor Tamp, and a capacitive element C2. The optical sensor 5 is interposed between a power supply line to which a fixed power supply potential Vs is supplied and a ground line, and a ground potential is supplied to the anode.

  A transistor Tc is interposed between the feeder line and the optical sensor 5. The transistor Tc functions as a switching element, and a detection control line ZBp is connected to its gate. That is, the transistor Tc is turned on only during a period in which the reset signal SRSTp is at the active level, and the power supply potential Vs is supplied to the cathode of the photosensor 5. A capacitive element C2 is interposed between the source and drain of the transistor Tc.

  On the other hand, an amplifying transistor Tamp is interposed between the power supply line supplied with the power supply potential Vs and the sense line Wq, and a transistor Td is interposed between the amplifying transistor Tamp and the sense line Wq. . The drain of the amplification transistor Tamp is connected to the power supply line, the source is connected to the drain of the transistor Td, and the gate is connected to the cathode of the photosensor 5. The source of the transistor Td is connected to the sense line Wq, and the gate is connected to the detection control line ZAp. That is, the transistor Td is turned on only during a period in which the selection signal SELp is in the active level, and a signal corresponding to the gate potential of the amplification transistor Tamp is supplied to the sense line Wq.

  In the sensing circuit S, the detection reset operation, the exposure operation, and the read operation are performed cyclically at a constant cycle. This period coincides with a length of 1V. In the detection reset period in which the detection reset operation is performed, as shown in FIG. 9, the transistor Tc is turned on and the transistor Td is turned off. Therefore, the potential of the gate of the amplification transistor Tamp (the potential of the cathode of the photosensor 5) is set (reset) to the power supply potential Vs.

  In the exposure period in which the exposure operation is performed, both the transistor Tc and the transistor Td are turned off as shown in FIG. In this period, the photosensor 5 generates a photocurrent corresponding to the amount of received light. Therefore, in the exposure period, the potential of the gate of the amplification transistor Tamp becomes the power supply potential Vs at the start of this period, and becomes a potential corresponding to the amount of light received by the photosensor 5 at the end of this period.

  In the reading period in which the reading operation is performed, as shown in FIG. 11, the transistor Tc is turned off and the transistor Td is turned on. Further, in the reading period, the potential of the gate of the amplification transistor Tamp is maintained by the capacitive element C2. Therefore, in the reading period, a detection signal corresponding to the gate potential of the amplification transistor Tamp is supplied from the amplification transistor Tamp to the sense line Wq.

  FIG. 12 is a timing chart for explaining the operation of the electro-optical device 100. In the electro-optical device 100, 1V repeatedly visits and 1H visits n times each 1V. 1V is a vertical scanning period, which is a period from when each light emitting circuit E in the first row starts a writing operation to when each light emitting circuit E in the first row starts a next writing operation. 1H is a horizontal scanning period, and the write signal WRTi related to the light-emitting circuit E in the i-th row maintains the active level over the i-th 1H, and maintains the inactive level in other periods. Since the reset signal ERSTi and the light emission signal ELi related to the light emitting circuit E in the i-th row maintain the inactive level during the period in which the write signal WRTi is in the active level, the i-th 1H is the light emitting circuit E in the i-th row This is also a writing period.

  The reset signal ERSTi maintains the active level in the period before the start of the writing period related to the light emitting circuit E in the i-th row, and maintains the inactive level in other periods. Since the write signal WRTi and the light emission signal ELi maintain the inactive level during the period in which the reset signal ERSTi is in the active level, this period is a light emission reset period related to the light emitting circuit E in the i-th row.

  The light emission signal ELi maintains an active level during the period after the end of the writing period related to the light emitting circuit E in the i-th row and before the start of the light emission reset period related to the light-emitting circuit E in the i-th row. Maintain the inactive level. Since the write signal WRTi and the reset signal ERSTi maintain the inactive level during the period in which the light emission signal ELi is in the active level, this period is the light emission period related to the light emitting circuit E in the i-th row. When i <n, a part of the light emission period related to the light-emitting circuit E in the i-th row overlaps a part of the light-emission period related to the light-emitting circuit E in the i + 1-th row.

  On the other hand, the reset signal SRSTp related to the sensing circuit S in the p-th row is active level in the period after the start of the light-emitting period related to the light-emitting circuit E in the (p + 1) -th row and before the end of the light-emitting period related to the light-emitting circuit E in the p-th row. And maintain an inactive level in other periods. Since the selection signal SELp related to the p-th sensing circuit S maintains the inactive level during the period in which the reset signal SRSTp is in the active level, this period is a detection reset period related to the p-th sensing circuit S.

  The selection signal SELp maintains an active level in a period after the end of the detection reset period related to the sensing circuit S in the (p + 1) th row and before the end of the light emitting period related to the light emitting circuit E in the pth row. Maintain inactive level. Since the reset signal SRSTp maintains the inactive level during the period in which the selection signal SELp is in the active level, this period is a reading period related to the sensing circuit S in the p-th row.

  The period from the end of the detection reset period related to the sensing circuit S in the p-th row to the start of the reading period related to the sensing circuit S is the exposure period. The entire exposure period related to the sensing circuit S in the p-th row overlaps with a part of the light-emitting period related to the light-emitting circuit E in the p-th row and also overlaps a part of the light-emitting period related to the light-emitting circuit E in the p + 1-th row.

  As described above, the electro-optical device 100 is used in a device that can read out characters written on a document and input a stroke. The operation of the control circuit 15 is different between the case of reading a character and the case of inputting a stroke, and the control circuit 15 switches its operation based on a signal supplied from the outside. Hereinafter, the operation of the control circuit 15 in the case of reading a character is referred to as a first operation, and the operation of the control circuit 15 in the case of input of a stroke is referred to as a second operation.

  First, the first operation will be described. In this description, it is assumed that the characters written on the surface 21 of the document 20 shown in FIG. 13 are read out. As shown in FIG. 14, prior to the first operation, the electro-optical device 100 and the document 20 are arranged so that the surface 21 and the first substrate 1 face each other. Then, in the first operation, the control circuit 15 emits light so that all the light emitting elements 7 emit light with a constant luminance, more specifically, a constant voltage is written to all the light emitting circuits E. Control line drive circuit 11 and data line drive circuit 12 are controlled. By this control, all the light emitting elements 7 emit light with a constant luminance. A part of light emitted from each light emitting element 7 passes through the first substrate 1 and reaches the surface 21, and a part of the light is reflected by the surface 21. Part of the reflected light from the surface 21 passes through the first substrate 1 and enters the optical sensor 5.

  On the other hand, the control circuit 15 controls the detection control line driving circuit 13 and the reading circuit 14 so as to read the detection results from all the sensing circuits S in order for each row and generate an image signal. As is clear from FIGS. 1 and 12, the exposure period related to the sensing circuit S in a certain row (for example, p-th row) is the light-emitting period related to the light-emitting circuit E in both adjacent rows (for example, p-th row and p + 1-th row). Therefore, if no light is written on the surface 21 and the light reflectance of the surface 21 is uniform, the amount of reflected light incident on all the optical sensors 5 is substantially the same. Become. Therefore, the image signal generated in the first operation is an image (n−1 rows and m−1 columns) corresponding to the light reflectance distribution of the surface 21 (distribution between the region occupied by characters on the surface 21 and other regions). The gradation of the pixel).

  The control circuit 15 generates image data based on the image signal supplied from the readout circuit 14 and supplies the image data to an external device. This external device includes a sound generation unit such as a speaker, and when the control circuit 15 performs the first operation, recognizes the character described on the surface 21 based on the supplied image data, and recognizes the recognized character. The natural language analysis is performed based on the above, and the pronunciation part is caused to pronounce the words obtained by this analysis. Thus, the characters written on the surface 21 are read out. In other words, an electronic device including the electro-optical device 100 and an external device is an electronic device that reads an image from a document, recognizes a character from the read image, and converts the recognized character into sound. This feature is particularly useful for people who have difficulty reading small letters.

  Next, the second operation will be described. In this description, it is assumed that the user of the electro-optical device 100 inputs the stroke of the pen 30 as shown in FIG. Prior to the second operation, the electro-optical device 100 is placed on the desk 40 with the second substrate 4 facing down. The input of the stroke in the present embodiment is performed in order to acquire a technique for writing characters beautifully, and the user can trace the example displayed on the electro-optical device 100 with the tip 31 of the pen 30. Enter strokes.

  In the second operation, the control circuit 15 is more specifically configured to display a model image, more specifically, so that each light emitting element 7 emits light with a luminance corresponding to the model image. The light emission control line drive circuit 11 and the data line drive circuit 12 are controlled so that the voltage corresponding to the model image is written in all the light emission circuits E. This control is performed based on image data supplied from an external device, and is repeatedly performed at a time interval corresponding to 1V. By this control, all the light emitting elements 7 emit light with a luminance corresponding to the model image. Since part of the light emitted from each light emitting element 7 is transmitted through the first substrate 1, a model image is displayed on the first substrate 1. As an example image, an image 50 shown in FIG. 16 can be exemplified. The image 50 is a model image of the characters “A”, “I”, and “U”.

  In the second operation, similarly to the first operation, the control circuit 15 reads the detection results from all the sensing circuits S in order for each row and generates the image signal to read the detection control line drive circuit 13 and the readout operation. The circuit 14 is controlled. However, this control is repeatedly performed at time intervals corresponding to 1V. Therefore, in the second operation, image signals are repeatedly generated, and each image signal indicates an image (the gradation of pixels in the (n−1) rows and (m−1) columns) corresponding to the position of the tip 31 on the first substrate 1. It becomes. This image includes pixels of n−1 rows and m−1 columns, and the gradation of each pixel corresponds to the amount of external light incident on each photosensor 5. When the model is traced with the tip 31 of the pen 30, the tip 31 functions as a light shielding layer, so that the amount of external light incident on the optical sensor 5 immediately below the tip 31 is reduced, and the external light incident on the other optical sensor 5 is reduced. The amount of light increases.

  The control circuit 15 generates image data based on the image signal supplied from the readout circuit 14 and supplies the image data to an external device. This external device includes a storage unit such as a memory for holding various data, and when the control circuit 15 performs the second operation, an image of the model is stored from the storage unit every period corresponding to 1V. Is read out and supplied to the control circuit 15. On the basis of the image data from the control circuit 15, the position designated using the pen 30 is specified and held in the storage unit, and held in the storage unit. The image data held in the storage unit is changed based on the position.

  Therefore, when the model image is the image 50 of FIG. 16, when the user traces the characters “A” and “I” with the tip 31 of the pen 30, the image displayed on the first substrate 1 is, for example, FIG. It becomes as shown in. That is, handwriting is reflected in the image displayed on the first substrate 1. On the other hand, in the second operation, since the image signal is repeatedly generated at a time interval corresponding to 1V, the external device can specify the stroke. How to use the stroke specified by the external device is arbitrary. For example, it may be possible to determine the suitability of a stroke by comparing the specified stroke with a predetermined stroke, or by identifying the stroke order from the identified stroke and comparing this stroke order with the correct stroke order. Thus, the correctness of the writing order may be determined.

  As described above, the electro-optical device 100 includes the transparent first substrate 1, the optical sensor 5 that is formed on the first substrate 1 and receives light from the first substrate 1 and detects the amount of received light. A second substrate 4 sandwiching the optical sensor 5 between the first substrate 1 and a light emitting element 7 sandwiched between the second substrate 4 and the optical sensor 5 are provided. A part of the light emitted from the light-emitting element 7 travels toward the first substrate 1, passes through the first substrate 1, and of the transmitted light, the light reflected by the document 20 and the pen 30 (reflected light). Is transmitted through the first substrate 1 and received by the optical sensor 5. In addition, when the electro-optical device 100 reads an image from the document 20 with the surface of the first substrate 1 opposite to the surface of the second substrate 4 facing the document 20, the electro-optical device 100 includes a placement surface such as a desk 40 and the like. When the first substrate 1 is sandwiched between the second substrate 4 and all the light emitting elements 7 emit light with a common luminance to display an image, the mounting surface and the first substrate 1 With the second substrate 4 sandwiched therebetween, the luminance of all the light emitting elements is individually controlled based on the image to be displayed. Therefore, according to the electro-optical device 100, an image is displayed by controlling the luminance of the light emitting element 7, a position indicated by the pen 30 in the image is detected, and an image is read from the document 20. Can do. That is, according to the electro-optical device 100, it is possible to both read an image from the original 20 and input information by pointing the position in the displayed image with the pen 30.

  By the way, the electro-optical device 100 employs an organic EL element that emits light traveling in all directions as the light-emitting element 7. For this reason, there is a concern that the light emitted from the light-emitting element 7 directly enters the optical sensor 5, leading to a decrease in image reading accuracy and a decrease in position detection accuracy. However, since the electro-optical device 100 includes the light shielding layer 6 that blocks light between the light emitting element 7 and the optical sensor 5, the above-described accuracy does not decrease.

  In the electro-optical device 100, the first substrate 1 and the second substrate 4 are transparent, so that the light from the light emitting element 7 passes through the first substrate 1 and the second substrate 4. That is, the electro-optical device 100 is a so-called dual emission type light emitting device. Therefore, an image can be displayed on both the first substrate 1 and the second substrate 4. The brightness of the image displayed on the first substrate 1 depends on the amount of light shielded by the light shielding layer 6, but the brightness of the image displayed on the second substrate 4 does not depend on the amount of light shielded by the light shielding layer 6. Therefore, the electro-optical device 100 has an advantage that a bright image can be displayed as compared with a so-called bottom emission type light emitting device. Of course, if these advantages are unnecessary, the electro-optical device 100 may be modified to be a bottom emission type in which the light from the light emitting element 7 transmits the first substrate 1 but does not transmit the second substrate 4.

  The electro-optical device 100 includes a plurality of optical sensors 5 and light-emitting elements 7. On the surface parallel to the first substrate 1, these optical sensors 5 are arranged in a grid pattern, and these light emitting elements 7 are also arranged in a grid pattern. Therefore, according to the electro-optical device 100, variations in image display resolution, image reading accuracy, and position detection accuracy on the surface can be suppressed. In addition, each of these optical sensors 5 does not overlap any light emitting element 7 in plan view. Therefore, according to the electro-optical device 100, the amount of light blocked by the light blocking layer 6 among the light emitted from the light emitting element 7 can be suppressed. That is, the electro-optical device 100 has an advantage that an image displayed on the first substrate 1 does not become so dark.

  Note that the above-described embodiment may be modified so that an image showing an enlarged recognized character is displayed on the electro-optical device 100. Since the electro-optical device 100 is a dual emission type light emitting device, the user can visually recognize this image without turning the electro-optical device 100 over. Moreover, the form which controls the brightness | luminance of a light emitting element based on the detection result of an optical sensor is not restricted to the form mentioned above. For example, a trace traced by the user with the tip 31 of the pen 30 may be displayed in a color different from that of the model character.

  Further, the above-described embodiment may be modified so that the light shielding layer 6 is omitted, the second substrate 4 may be opaque, and the electro-optical device 100 may be used for reading an image from a document, a pen, You may use for the apparatus used only for any one among the detection uses of the position instruct | indicated with pointing objects, such as a finger | toe. When used in an apparatus used only for reading an image from a document, the number of light emitting elements 7 may be one.

  In the above-described embodiment, the input of the handwriting is exemplified as the use for detecting the position indicated by the pointing object such as the pen or the finger. However, the present invention is not limited to this. As such an example, an alphabet of 26 characters is displayed and an alphabet at a position indicated by an indicator is input, or an icon associated with information is displayed and an icon indicated by an indicator An example of inputting information corresponding to is given. Of course, the input information may be output as audio. This form is convenient for those who have difficulty speaking.

  In the embodiment described above, the sensing circuits S in each row are scanned at a time interval corresponding to 1H, but this is modified so that the sensing circuits S in each row are scanned at a time interval different from the time corresponding to 1H. It may be. In the above-described embodiment, each sensing circuit S outputs a detection signal at a time interval corresponding to 1V, but this is modified so that each sensing circuit S has a detection signal at a time interval different from the time corresponding to 1V. May be output. Further, the embodiment described above may be modified so that the number of photosensors 5 is larger than the number of light emitting elements 7, or the photosensors 5 and the light emitting elements 7 are arranged in a pattern different from the pattern shown in FIG. May be.

  Next, an electronic apparatus using the electro-optical device 100 will be described. FIG. 18 is a perspective view illustrating a configuration of a mobile personal computer that employs the electro-optical device 100 as a display unit. The personal computer 2000 includes the electro-optical device 100 and a main body 2010. The main body 2010 is provided with a power switch 2001 and a keyboard 2002.

  FIG. 19 shows a configuration of a mobile phone to which the electro-optical device 100 is applied. A cellular phone 3000 includes a plurality of operation buttons 3001, scroll buttons 3002, and the electro-optical device 100. By operating the scroll button 3002, the image displayed on the electro-optical device 100 can be scrolled.

  FIG. 20 shows a configuration of a personal digital assistant (PDA) to which the electro-optical device 100 is applied. The portable information terminal 4000 includes a plurality of operation buttons 4001, a power switch 4002, and the electro-optical device 100. Note that electronic apparatuses to which the electro-optical device according to the invention is applied are not limited to those shown in FIGS.

DESCRIPTION OF SYMBOLS 1 ... 1st board | substrate, 100 ... Electro-optical device, 2 ... Circuit layer, 3 ... Light source layer, 4 ... 2nd board | substrate, 5 ... Photosensor, 6 ... Light-shielding layer, 7 ... Light emitting element , E: Light emitting circuit, S: Sensing circuit.

Claims (8)

A transparent first substrate;
An optical sensor that is formed on the first substrate and receives light from the first substrate to detect a received light amount;
A second substrate sandwiching the photosensor with the first substrate;
An electro-optical device comprising: a light emitting element that is sandwiched between the second substrate and the optical sensor and emits light toward the first substrate. The electro-optical device according to claim 1, further comprising a light blocking layer that blocks light between the light emitting element and the optical sensor. The electro-optical device according to claim 1, wherein the second substrate is transparent. A plurality of the light sensors and the light emitting elements, respectively,
4. The electro-optical device according to claim 1, wherein each of the plurality of optical sensors does not overlap any of the plurality of light-emitting elements in a plan view.   An electronic apparatus comprising the electro-optical device according to claim 1. An electro-optical device according to claim 4,
The plurality of light emitting elements emit light with a common luminance, read an image from a document facing a surface opposite to the surface of the first substrate on the second substrate side, recognize characters from the read image, An electronic device that converts recognized characters into speech. An electro-optical device according to claim 4,
Placed on the placement surface,
When reading an image from the original with the surface opposite to the second substrate side of the first substrate facing the original, the first substrate is placed between the placement surface and the second substrate. In the case where the image is displayed and the second substrate is sandwiched between the mounting surface and the first substrate when the image is displayed. The method of driving an electro-optical device according to claim 4,
When reading an image from the original with the surface opposite to the second substrate side of the first substrate facing the original, the plurality of light emitting elements emit light with a common luminance,
In the case of displaying an image, the luminance of the plurality of light emitting elements is individually controlled based on the image to be displayed.

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