JP2011086030A - Display device with position detecting function - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a display device with a position detecting function which can form intensity distribution of position detecting light for detecting the position of an object on the screen face side of a screen member where an image is visible. <P>SOLUTION: In the display device 100 with the position detecting function, the screen member 8 includes a light shielding layer 80 on the back side 8b, and a plurality of light transmitting parts 81 are formed on the light shielding layer 80. A plurality of position detecting light sources 12 directing the light emitting parts toward the light transmitting parts 81 are arranged on the back side 8b of the screen member 8. When the light emission quantity of the plurality of position detecting light sources 12 is controlled, the position detecting light L2 made of infrared rays emitted from the position detecting light source 12 forms the intensity distribution of the position detecting light L2 on the screen face 8a passing through the screen member 8, and thereby, the position detecting light L2 reflected by the object Ob at the screen face 8a can be detected by a photodetector 30. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a display device with a position detection function capable of projecting an image and optically detecting the position of a target object in a detection region set on the image projection side.

  In recent years, electronic devices such as mobile phones, car navigation systems, personal computers, ticket machines, and bank terminals have used display devices with a position detection function in which a touch panel is arranged on the front surface of an image generation device such as a liquid crystal device. The display device with a detection function inputs information while referring to an image displayed on the image generation device. Such a touch panel is configured as a position detection device for detecting the position of a target object within a detection region (see, for example, Patent Document 1).

  In such a position detection device described in Patent Document 1, a light-transmitting plate is provided on the input operation side with respect to a direct-view display panel such as a liquid crystal panel, and a light source and a light receiver are provided on the opposite side of the light-transmitting plate from the input operation side. Arrange elements and the like. Then, the position detection light emitted from the light source is emitted to the input operation side through the translucent plate, and the position detection light reflected by the target object is received by the light receiving element.

US Patent No. No. 6927384

  The inventor of the present application proposes a display device with a position detection function that displays an image on a screen member and detects the position of a target object on the front side (screen surface side) of the screen member. However, in such a display device with a position detection function, it is impossible to provide the light transmitting plate, the light source, and the light receiving element on the front side of the screen member, and thus the configuration described in Patent Document 1 cannot be employed.

  In view of the above problems, an object of the present invention is to provide position detection that can form an intensity distribution of position detection light for detecting the position of a target object on the screen surface side where an image is visually recognized on a screen member. It is to provide a display device with a function.

  In order to solve the above problems, the present invention provides a display device with a position detection function that detects a position of a target object located on a screen surface side where an image is visually recognized on a screen member by position detection light reflected by the target object. The screen member has translucency with respect to the position detection light, and the light emitting portion is directed to the screen member on the back side opposite to the screen surface side of the screen member. A plurality of position detection light sources that emit position detection light to form an intensity distribution of the position detection light on the screen surface side, a light source driving unit that drives the position detection light source, and the screen surface side And a photodetector for detecting the position detection light reflected by the target object.

  In the present invention, the “screen member” means a screen member used for an electronic blackboard in addition to the irradiated member used in the projection display device.

  In the present invention, when the position detection light source emits position detection light, the position detection light passes through the screen member and forms an intensity distribution of the position detection light on the screen surface side. Accordingly, when the position detection light is reflected by the target object located on the screen surface side, the position detection light is detected by the photodetector. Therefore, if the relationship between the position on the screen surface side and the intensity of the position detection light is grasped in advance, the position of the target object can be detected based on the light reception result of the photodetector.

  In the present invention, the position detection light is preferably infrared light. If comprised in this way, the visual recognition of the image formed in the screen member by the position detection light is not prevented.

  In the present invention, the screen member includes a light shielding layer on the back surface side, and the light shielding layer includes a plurality of light-transmitting portions that allow the position detection light to pass therethrough. It is preferable that the light emitting part is directed to the light transmitting part. If comprised in this way, since the position detection light radiate | emitted from the light source for position detection passes through a screen member efficiently, the intensity distribution of position detection light can be reliably formed in the screen surface side.

  In the present invention, the light source driving unit controls lighting of each of the plurality of position detection light sources, and the intensity distribution is a first coordinate detection intensity whose intensity changes in a first direction along the screen surface as the intensity distribution. It is preferable that the distribution and the second coordinate detection intensity distribution whose intensity changes in the second direction along the screen surface intersecting the first direction are formed with different timings. If comprised in this way, the coordinate of the target object in the plane along a screen surface is detectable.

  In this invention, the said light source drive part is 1st intensity | strength for 1st coordinate detection from which the intensity | strength of the said position detection light falls toward the other side from the one side of the said 1st direction as said 1st coordinate detection intensity distribution. A distribution and a second coordinate detection second intensity distribution in which the intensity of the position detection light decreases from the other side to the one side in the first direction at different timings, and the second coordinate detection intensity As the distribution, the second coordinate detection first intensity distribution in which the intensity of the position detection light decreases from one side in the second direction toward the other side, and the first direction from the other side in the second direction toward the one side. It is preferable to form the second coordinate detection second intensity distribution in which the intensity of the position detection light decreases at different timings. If comprised in this way, the coordinate of a 1st direction can be detected with the 1st intensity distribution for 1st coordinate detection, and the 2nd intensity distribution for 1st coordinate detection, and the 1st intensity distribution for 2nd coordinate detection and the 1st intensity distribution The coordinates in the second direction can be detected by the second intensity distribution for detecting two coordinates. Therefore, the coordinates of the target object in the plane along the screen surface can be detected with high accuracy.

  In the present invention, when the light source driving unit forms the first coordinate detection intensity distribution, the light source drive unit makes a light emission amount different between the position detection light sources provided at positions shifted in the first direction, When forming the second coordinate detection intensity distribution, it is possible to adopt a configuration in which the light emission amount is different between the position detection light sources provided at positions shifted in the second direction.

  In the present invention, the light-shielding layer includes, as the plurality of light-transmitting portions, a first group of light-transmitting portions having different light transmission amounts in the first direction and a light transmission amount different in the second direction. And the light source driving unit directs the light emitting unit to the light transmitting unit of the first group when forming the first coordinate detection intensity distribution. When the second coordinate detection intensity distribution is formed, the position detection light source that directs the light emitting part to the light transmitting part of the second group may be turned on. If comprised in this way, the said position detection light source which orient | assigns a light emission part to the light transmission part of a 1st group, and the said position detection light source which orient | assigns a light emission part to the light transmission part of a 2nd group are turned on alternately. The coordinates of the target object in the plane along the screen surface can be detected.

  In this case, when the light source driving unit forms the first coordinate detection intensity distribution, the light source drive unit varies the light emission amount between the position detection light sources provided at positions shifted in the first direction, and When forming the two-coordinate detection intensity distribution, the light emission amount may be different between the position detection light sources provided at positions shifted in the second direction. If comprised in this way, since appropriate intensity distribution can be formed in the screen surface side, the coordinate of the target object in the plane along a screen surface can be detected accurately.

  The display device with a position detection function to which the present invention is applied can be configured as a projection display device. In this case, the display device with a position detection function includes an image projection device that projects an image toward the screen surface. ing.

  In the present invention, it is preferable that the photodetector has a light receiving portion directed in a direction along the screen surface. With this configuration, since the distance from the screen surface that can detect the target object is limited, only the position of the target object near the screen surface can be detected.

  In the present invention, the photodetector may employ a configuration in which a light receiving portion is directed to the screen surface from an out-of-plane direction of the screen surface. If comprised in this way, the separation distance from the screen surface which can detect a target object can be expanded.

  In adopting such a configuration, when the display device with a position detection function is configured as a projection display device, it is preferable to mount the photodetector on the image projection device. If comprised in this way, it is not necessary to install a photodetector separately from an image projection apparatus. Further, processing for detecting the position of the target object can be performed on the image projection apparatus side. Furthermore, it is easy to reflect the position detection result of the target object in the image projected from the image projection apparatus.

It is explanatory drawing which shows typically the structure of the display apparatus with a position detection function which concerns on Embodiment 1 of this invention. It is explanatory drawing which shows the electrical structure etc. of the display apparatus with a position detection function to which this invention is applied. It is explanatory drawing which shows the basic content of operation | movement in the intensity distribution of a position detection light used with the display apparatus with a position detection function to which this invention is applied, and a position detection part. It is explanatory drawing which shows the structure of the translucent part of a screen member and the light source for position detection in the display apparatus with a position detection function which concerns on Embodiment 1 of this invention. It is explanatory drawing which shows a mode that the intensity distribution of a position detection light is formed in the display apparatus with a position detection function which concerns on Embodiment 1 of this invention. It is explanatory drawing which shows the structure of the translucent part of the screen member and the light source for position detection in the display apparatus with a position detection function which concerns on Embodiment 2 of this invention. It is explanatory drawing which shows a mode that the intensity distribution of a position detection light is formed in the display apparatus with a position detection function which concerns on Embodiment 2 of this invention. It is explanatory drawing which shows typically the structure of the display apparatus with a position detection function which concerns on Embodiment 3 of this invention.

  Next, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, the directions intersecting each other in a plane parallel to the screen surface are defined as the X axis and the Y axis, and the out-of-plane direction with respect to the screen surface is defined as the Z axis. In the drawings referred to below, for convenience of explanation, the X-axis direction is represented as a horizontal direction and the Y-axis direction is represented as a vertical direction. In the drawings referred to below, one side in the X-axis direction is the X1 side, the other side is the X2 side, one side in the Y-axis direction is the Y1 side, and the other side is the Y2 side. In the drawings referred to in the following description, the scales are different for each layer and each member so that each layer and each member have a size that can be recognized on the drawing. Further, in the drawings referred to in the following description, the number of the light transmitting parts and the position detection light source is reduced so as to be easily recognized.

[Embodiment 1]
(Overall configuration of display device with position detection function)
FIG. 1 is an explanatory view schematically showing a configuration of a display device with a position detection function according to Embodiment 1 of the present invention. FIGS. 1 (a) and 1 (b) are views of the display device with a position detection function. It is explanatory drawing which shows a mode that the part was seen from diagonally upward, and explanatory drawing which shows a mode that it looked at from the horizontal direction. FIG. 2 is an explanatory diagram showing an electrical configuration and the like of a display device with a position detection function to which the present invention is applied. In FIG. 1A, the translucent part is indicated by a dotted circle, and the position detection light source is indicated by a dotted square.

  A display device with a position detection function 100 shown in FIGS. 1A and 1B includes a projection display device including an image projection device 200 called a liquid crystal projector or a digital micromirror device, and a screen member 8. It is configured as. The image projection apparatus 200 enlarges and projects the image display light L <b> 1 toward the screen member 8 from the projection lens system 210 provided on the front surface portion 201 of the housing 250.

  The display device with a position detection function 100 according to this embodiment includes an optical position detection device 10, and the optical position detection device 10 is on the screen surface 8 a side (in front of the screen member 8) where an image is visually recognized on the screen member 8. Is provided with a function of optically detecting the position of the target object Ob in the detection region 10R set to. The detection area 10 </ b> R overlaps the area (image display area 20 </ b> R) on the screen member 8 where an image is projected by the image projection apparatus 200. For this reason, in the display device with a position detection function 100 according to the present embodiment, for example, the coordinate detection result of the target object Ob is treated as input information for designating a part of the projected image and the like, and the image is based on the input information. Switching of etc. is performed.

  As will be described in detail later, the optical position detection device 10 includes a plurality of position detection light sources 12 having a light emitting portion directed toward the screen member 8 on the back surface 8b opposite to the screen surface 8a side of the screen member 8, and And a photodetector 30 having the light receiving portion 31 facing the detection region 10R on the screen surface 8a side. Here, the screen member 8 has translucency with respect to the position detection light L2. Therefore, when the position detection light source 12 emits the position detection light L2 from the light emitting portion toward the screen member 8, the position detection light L2 passes through the screen member 8 and forms an intensity distribution described later on the screen surface 8a side. To do.

  In the present embodiment, the photodetector 30 is composed of a light receiving element such as a photodiode or a phototransistor, and on the screen surface 8a side of the screen member 8, the light receiving unit 31 is arranged outside the detection region 10R in a direction along the screen surface 8a. It is aimed. Therefore, the photodetector 30 can detect the position detection light L3 reflected by the target object Ob.

  The position detection light source 12 includes a light emitting diode mounted on the substrate 120, and emits position detection light L2 as diverging light. The position detection light L2 preferably has a wavelength range that is efficiently reflected by the target object Ob such as a finger or a touch pen. Therefore, if the target object Ob is a human body such as a finger, it is desirable that the infrared ray has a high reflectivity on the surface of the human body (particularly near infrared light close to the visible light region, for example, near 850 nm in wavelength) or 950 nm. In this embodiment, any position detection light source 12 emits infrared light having a peak wavelength in a wavelength region near 850 nm.

  The screen member 8 includes a white screen 85 on the screen surface 8a side. As the screen 85, a white screen made of a cloth coated with white paint on the screen surface 8a side or an embossed white vinyl material is used. Can be used. Further, as the screen 85, a silver screen having a high silver color in order to increase the reflectance of light can be used. Further, as the screen 85, a pearl screen in which the fabric surface constituting the screen surface 8a side is subjected to resin processing to increase the light reflectivity, or fine glass powder is applied to the screen surface 8a side to increase the light reflectivity. An elevated piece screen can also be used. In any case, the screen 85 has translucency with respect to the position detection light L2 made of infrared light.

  The screen member 8 of the present embodiment includes a black light shielding layer 80 on the back surface side 8b of the screen 85 for the purpose of improving the quality of an image displayed on the screen 85. The light shielding layer 80 includes infrared light. The position detection light L2 consisting of Here, the light-shielding layer 80 has a plurality of light-transmitting portions 81 formed of holes, and the distance between the light-transmitting portions 81 is 10 mm to several tens of mm. Further, the position detection light source 12 and the translucent part 81 are provided in a one-to-one relationship, and each of the plurality of position detection light sources 12 has the light emitting part directed toward the translucent part 81. For this reason, the screen member 8 has translucency with respect to the position detection light L2. Accordingly, when the position detection light source 12 emits the position detection light L2 from the light emitting portion toward the screen member 8, the position detection light L2 passes through the screen member 8 and forms an intensity distribution on the screen surface 8a side. become. In the screen member 8, the light shielding layer 80 may be omitted.

  As shown in FIG. 2, the optical position detection device 10 determines the position of the target object Ob based on the detection result of the light source driving unit 14 that drives each of the plurality of position detection light sources 12 and the light detector 30. And a position detection unit 50 for detection. The light source drive unit 14 includes a drive circuit 140 corresponding to each of the plurality of position detection light sources 12 and a light source control unit 145 that controls lighting of each of the plurality of position detection light sources 12 via the drive circuit 140. ing. The position detection unit 50 includes an X coordinate detection unit 51 that detects a position (X coordinate) of the target object Ob in the X axis direction among the X axis direction and the Y axis direction intersecting at right angles in a plane parallel to the screen 85. A Y-coordinate detection unit 52 that detects the position (Y-coordinate) of the target object Ob in the Y-axis direction. Further, the position detection unit 50 includes a Z coordinate detection unit 53 that detects the position (Z coordinate) of the target object Ob in the Z axis direction orthogonal to the screen 85. The light source control unit 145 and the position detection unit 50 are connected by a signal line, and driving of the position detection light source 12 and detection operation by the position detection unit 50 are performed in conjunction with each other.

(Basic principle of coordinate detection)
In the display device with a position detection function 100 according to this embodiment, the position detection unit 50 detects the position of the target object Ob in the detection region 10R using the intensity distribution of the position detection light L2 formed on the screen surface 8a side. To do. Therefore, the configuration of the light intensity distribution and the principle of coordinate detection will be described with reference to FIG.

  FIG. 3 is an explanatory diagram showing the intensity distribution of the position detection light L2 used in the display device with a position detection function 100 to which the present invention is applied and the basic operation contents in the position detection unit 50. FIG. , (B), (c) are explanatory diagrams showing the intensity distribution in the X-axis direction of the position detection light L2, explanatory diagrams showing the intensity of the position detection light L2 reflected by the target object, and position detection light reflected by the target object It is explanatory drawing which shows a mode that the intensity distribution of the position detection light L2 is adjusted so that the intensity | strength of L2 may become equal.

  When the position detection light L2 is emitted from the position detection light source 12 in the optical position detection device 10 of the display device 100 with the position detection function shown in FIG. Thus, the intensity distribution of the position detection light L2 is formed. For example, when detecting the X coordinate, as shown in FIGS. 3A and 3B, first, in the first period for X coordinate detection, from one side X1 in the X axis direction toward the other side X2. After forming the first intensity distribution L2Xa for X coordinate detection whose intensity decreases monotonically, the intensity decreases monotonously from the other side X2 in the X axis direction toward the one side X1 in the second period for X coordinate detection. A second intensity distribution L2Xb for detecting X coordinates is formed. Preferably, in the first period for X coordinate detection, after forming the first intensity distribution L2Xa for X coordinate detection in which the intensity decreases linearly from one side X1 in the X-axis direction to the other side X2, X In the second coordinate detection period, an X coordinate detection second intensity distribution L2Xb is formed in which the intensity decreases linearly from the other side X2 in the X-axis direction toward the one side X1. Therefore, when the target object Ob is arranged in the detection region 10R, the position detection light L2 is reflected by the target object Ob, and a part of the reflected light is detected by the photodetector 30. Here, the X coordinate detection first intensity distribution L2Xa formed in the first X coordinate detection period and the X coordinate detection second intensity distribution L2Xb formed in the second X coordinate detection period are set as distributions set in advance. If so, the X coordinate of the target object Ob can be detected based on the detection result of the photodetector 30 by the following method or the like.

  For example, in the first method, the difference between the X coordinate detection first intensity distribution L2Xa shown in FIG. 3B and the X coordinate detection second intensity distribution L2Xb is used. More specifically, since the first intensity distribution L2Xa for X coordinate detection and the second intensity distribution L2Xb for X coordinate detection are set in advance, the first intensity distribution L2Xa for X coordinate detection and the X coordinate are set. The difference from the detection second intensity distribution L2Xb is also a function set in advance. Therefore, the detection value LXa at the photodetector 30 when the first X coordinate detection intensity distribution L2Xa is formed in the first X coordinate detection period and the second intensity for X coordinate detection in the second period for X coordinate detection. If the difference from the detection value LXb at the light detector 30 when the distribution L2Xb is formed is obtained, the X coordinate detection unit 51 of the position detection unit 50 can detect the X coordinate of the target object Ob. According to this method, even when ambient light other than the position detection light L2, for example, an infrared component included in external light is incident on the light detector 30, when obtaining the difference between the detection values LXa and LXb, Since the intensity of the included infrared component is offset, the infrared component included in the ambient light does not affect the detection accuracy.

  Next, in the second method, the detection value LXa at the photodetector 30 when the first intensity distribution L2Xa for X coordinate detection is formed in the first period for X coordinate detection, and the second period for X coordinate detection. The adjustment amount when the control amount (drive current) for the position detection light source 12 is adjusted so that the detection value LXb at the photodetector 30 when the second intensity distribution L2Xb for X coordinate detection is formed becomes equal. This is a method for detecting the X-coordinate of the target object Ob based on this. This method can be applied when the X coordinate detection first intensity distribution L2Xa and the X coordinate detection second intensity distribution L2Xb shown in FIG. 3B change linearly with respect to the X coordinate.

  First, as shown in FIG. 3B, the X coordinate detection first intensity distribution L2Xa and the X coordinate detection second intensity distribution L2Xb are absolute values in the first X coordinate detection period and the second X coordinate detection period. Are formed in the opposite direction in the X-axis direction. In this state, if the detection value LXa at the photodetector 30 in the first period for X coordinate detection is equal to the detection value LXb at the photodetector 30 in the second period for X coordinate detection, the target object Ob is X It can be seen that it is located in the axial center.

  On the other hand, when the detection value LXa at the photodetector 30 in the first period for X coordinate detection is different from the detection value LXb at the photodetector 30 in the second period for X coordinate detection, detection is performed. The control amount (drive current) for the position detection light source 12 is adjusted so that the values LXa and LXb are equal. Then, as shown in FIG. 3C, the X coordinate detection first intensity distribution L2Xa is formed again in the first X coordinate detection period, and the second intensity for X coordinate detection in the second period for X coordinate detection. A distribution L2Xb is formed. As a result, if the detection value LXa at the photodetector 30 in the first X coordinate detection period and the detection value LXb at the photodetector 30 in the second X coordinate detection period are equal, the X coordinate detection second period is detected. The position detection unit is based on the ratio or difference between the control amount adjustment amount ΔLXa for the position detection light source 12 in one period and the control amount adjustment amount ΔLXb for the position detection light source 12 in the second period for X coordinate detection. 50 X-coordinate detectors 51 can detect the X-coordinate of the target object Ob. According to this method, even when ambient light other than the position detection light L2, for example, an infrared component included in external light is incident on the photodetector 30, the position detection light source is set so that the detection values LXa and LXb are equal. When adjusting the control amount with respect to 12, the intensity of the infrared component contained in the ambient light is canceled out, so the infrared component contained in the ambient light does not affect the detection accuracy.

  Next, also in the third method, similarly to the second method, the detection value LXa at the photodetector 30 when the first intensity distribution L2Xa for X coordinate detection is formed in the first period for X coordinate detection, and X The control amount (drive current) for the position detection light source 12 is set so that the detection value LXb of the photodetector 30 when the second intensity distribution L2Xb for X coordinate detection is formed in the second period for coordinate detection is equal. This is a method of detecting the X coordinate of the target object Ob based on the adjustment amount at the time of adjustment. This method can be applied when the X coordinate detection first intensity distribution L2Xa and the X coordinate detection second intensity distribution L2Xb shown in FIG. 3B change linearly with respect to the X coordinate.

  First, as shown in FIG. 3B, the X coordinate detection first intensity distribution L2Xa and the X coordinate detection second intensity distribution L2Xb are absolute values in the first X coordinate detection period and the second X coordinate detection period. Are formed in the opposite direction in the X-axis direction. In this state, if the detection value LXa at the photodetector 30 in the first period for X coordinate detection is equal to the detection value LXb at the photodetector 30 in the second period for X coordinate detection, the target object Ob is X It can be seen that it is located in the axial center.

  On the other hand, when the detection value LXa at the photodetector 30 in the first period for X coordinate detection is different from the detection value LXb at the photodetector 30 in the second period for X coordinate detection, detection is performed. In order to make the values LXa and LXb equal, for example, the control amount (driving current) for the position detection light source 12 in the period where the detection value is low or in the period where the detection value is high is adjusted, and again the X coordinate A first intensity distribution L2Xa for X coordinate detection is formed in the first period for detection, and a second intensity distribution L2Xb for X coordinate detection is formed in the second period for X coordinate detection. In the example shown in FIG. 3B, for example, the control amount for the position detection light source 12 in the first X coordinate detection period is decreased by the adjustment amount ΔLXa. Alternatively, the control amount for the position detection light source 12 in the second period for X coordinate detection is increased by the adjustment amount ΔLXb. As a result, the control amount is adjusted if the detection value LXa at the photodetector 30 in the first period for X coordinate detection is equal to the detection value LXb at the photodetector 30 in the second period for X coordinate detection. The ratio or difference between the control amount for the position detection light source 12 in the subsequent X coordinate detection first period and the control amount for the position detection light source 12 in the second X coordinate detection period after adjusting the control amount. Thus, the X coordinate detection unit 51 of the position detection unit 50 can detect the X coordinate of the target object Ob. The X coordinate of the target object Ob can be detected. According to this method, even when ambient light other than the position detection light L2, for example, an infrared component included in external light is incident on the photodetector 30, the position detection light source is set so that the detection values LXa and LXb are equal. When adjusting the control amount with respect to 12, the intensity of the infrared component contained in the ambient light is canceled out, so the infrared component contained in the ambient light does not affect the detection accuracy.

  In the case where any of the above methods 1 to 3 is adopted, similarly, in the first period for Y coordinate detection, the Y coordinate detection in which the intensity monotonously decreases from one side Y1 in the Y axis direction toward the other side Y2. After the first intensity distribution is formed, the second intensity distribution for Y coordinate detection in which the intensity monotonously decreases from the other side Y2 in the Y-axis direction toward the one side Y1 in the second period for Y coordinate detection is formed. Then, the Y coordinate detection unit 52 of the position detection unit 50 can detect the Y coordinate of the target object Ob.

  Further, if an intensity distribution in the Z-axis direction is formed in the Z coordinate detection period, the Z coordinate detection unit 53 of the position detection unit 50 can detect the Z coordinate of the target object Ob.

  As described above, when acquiring position information in the detection region 10R of the target object Ob based on the detection result of the photodetector 30, for example, a microprocessor unit (MPU) is used as the position detection unit 50, thereby A configuration in which processing is performed according to execution of predetermined software (operation program) can be employed. In addition, a configuration in which processing is performed by a signal processing unit using hardware such as a logic circuit may be employed.

(Specific Configuration of Optical Position Detection Device 10)
FIG. 4 is an explanatory diagram showing the configuration of the light transmitting portion 81 of the screen member 8 and the position detecting light source 12 in the display device 100 with a position detecting function according to the first embodiment of the present invention. The light portion 81 is indicated by a solid circle, and the position detection light source 12 is indicated by a dotted square.

  In forming the intensity distribution of the position detection light L2 described with reference to FIG. 3, in this embodiment, as shown in FIGS. 1 (a) and 1 (b), the screen member 8 has a screen member on the back surface 8b. A plurality of position detection light sources 12 having a light emitting portion directed to 8 are arranged. Further, the screen member 8 has a black light shielding layer 80 formed on the back surface side 8b, and the light shielding layer 80 has a plurality of light transmitting portions 81 formed of holes. In addition, in each of the plurality of position detection light sources 12, the light emitting portion is directed toward the light transmitting portion 81.

  More specifically, as shown in FIG. 4, in the light shielding layer 80 of the screen member 8, a plurality of light transmitting portions 81 are formed in the X-axis direction and a plurality of rows are also formed in the Y-axis direction. In this embodiment, the translucent part 81 is formed in a matrix in the X-axis direction and the Y-axis direction as the translucent parts 81aa, 81ab... 81fe, 81ff. Here, the translucent part 81 consists of holes of the same size, and the transmitted light amount is equal.

  In addition, a plurality of position detection light sources 12 having a light emitting portion facing the light transmitting portion 81 are disposed on the back surface side 8 b of the screen member 8. In the present embodiment, the position detection light source 12 is matrixed in the X-axis direction and the Y-axis direction as the position detection light sources 12aa, 12ab... 12fe, 12ff so as to correspond to the light transmitting portion 81 in a one-to-one relationship. It is formed in a shape.

  For this reason, in the light source driving unit 14 shown in FIG. 2, a plurality of drive circuits 140 (in a one-to-one relationship with the plurality of position detection light sources 12 (position detection light sources 12aa, 12ab... 12fe, 12ff). Drive circuits 140aa, 140ab... 140fe, 140ff) are provided.

(X coordinate detection operation)
With reference to FIG. 5, an operation of detecting the position of the target object Ob in the detection region 10 </ b> R in the display device with a position detection function 100 according to the present embodiment will be described. FIG. 5 is an explanatory diagram showing a state in which the intensity distribution of the position detection light L2 is formed in the display device 100 with a position detection function according to the first embodiment of the present invention, and FIGS. FIGS. 5C and 5D are explanatory diagrams of an X-coordinate detection intensity distribution when detecting the X-coordinate of the target object Ob, and FIGS. 5C and 5D are Y-coordinate detection intensity when detecting the Y-coordinate of the target object Ob. It is explanatory drawing of distribution.

  In the display device 100 with a position detection function of the present embodiment, in order to detect the XY coordinates of the target object Ob in the detection region 10R, the X period is detected by the first period for X coordinate detection and the second period for X coordinate detection described below. The coordinate is detected, and the Y coordinate is detected by the first period for Y coordinate detection and the second period for Y coordinate detection. Furthermore, in the display device 100 with a position detection function of this embodiment, the Z coordinate is detected by the Z coordinate detection period. Here, each time from the first X coordinate detection period to the Z coordinate detection period is, for example, about several milliseconds.

More specifically, in order to detect the X coordinate of the target object Ob in the detection region 10R, first, in the first period for X coordinate detection, the light source controller 145 of the light source driver 14 shown in FIG. The position detection light source 12 is controlled via 140, and as shown in FIG. 5A, among the plurality of position detection light sources 12, the position detection light source 12 is moved from one side X1 to the other side X2 in the X-axis direction. The amount of light emitted from the light source 12 is reduced. At this time, the light emission amounts of the position detection light sources 12 arranged in the Y-axis direction are equal. The relationship between the light emission amounts is as follows in the position detection light source 12 shown in FIG. 4 (position detection light sources 12aa, 12ab... 12fe, 12ff): 12aa <12ab <12ac <12ad <12ae <12af
12aa = 12ba = 12ca = 12da = 12ea = 12fa
12ab = 12bb = 12cb = 12db = 12eb = 12fb
12ac = 12bc = 12cc = 12dc = 12ec = 12fc
12ad = 12bd = 12cd = 12dd = 12ed = 12fd
12ae = 12be = 12ce = 12de = 12ee = 12fe
12af = 12bf = 12cf = 12df = 12ef = 12ff
It is represented by

  As a result, the X coordinate detection first intensity distribution L2Xa (the first coordinate detection intensity distribution / first coordinate detection use) in which the intensity of the position detection light L2 monotonously decreases from one side X1 to the other side X2 in the X-axis direction. A first intensity distribution) is formed. In the first intensity distribution L2Xa for X coordinate detection of this embodiment, the intensity of the position detection light L2 continuously decreases substantially linearly from the one side X1 in the X axis direction toward the other side X2. In the first X coordinate detection first intensity distribution L2Xa, the position in the X-axis direction and the intensity of the position detection light L2 have a certain relationship. For this reason, the amount of light reflected by the target object Ob and detected by the light detector 30 is proportional to the intensity of the position detection light L2 in the first X-coordinate detection first intensity distribution L2Xa and is defined by the position of the target object Ob. Value.

  Next, in the second period for X-coordinate detection, the light source controller 145 of the light source driver 14 shown in FIG. 2 controls the position detection light source 12 via the drive circuit 140, as shown in FIG. 5B. In contrast to the first period for X coordinate detection, among the plurality of position detection light sources 12, the amount of light emitted from the position detection light source 12 is reduced from the other side X2 in the X-axis direction toward the one side X1. . At this time, the light emission amounts of the position detection light sources 12 arranged in the Y-axis direction are equal. As a result, the X coordinate detection second intensity distribution L2Xb (the first coordinate detection intensity distribution / first coordinate detection use) in which the intensity of the position detection light L2 monotonously decreases from the other side X2 in the X axis direction toward the one side X1. A second intensity distribution) is formed. In the second intensity distribution L2Xb for X coordinate detection of this embodiment, the intensity of the position detection light L2 continuously decreases substantially linearly from the other side X2 in the X-axis direction toward the one side X1. In the X-coordinate detection second intensity distribution L2Xb, the position in the X-axis direction and the intensity of the position detection light L2 have a certain relationship. For this reason, the amount of light reflected by the target object Ob and detected by the photodetector 30 is proportional to the intensity of the position detection light L2 in the X coordinate detection second intensity distribution L2Xb and is defined by the position of the target object Ob. Value.

  Therefore, the difference or ratio between the light amount detected by the photodetector 30 in the first period for X coordinate detection and the light amount detected by the photodetector 30 in the second period for X coordinate detection is the position of the target object Ob. Is a value defined by. Therefore, the X coordinate detection unit 51 of the position detection unit 50 determines the detection result of the photodetector 30 in the first period for X coordinate detection and the detection result of the photodetector 30 in the second period for X coordinate detection. Based on this, the X coordinate of the target object Ob can be detected.

(Y coordinate detection operation)
In order to detect the Y coordinate of the target object Ob in the detection region 10R, first, in the first period for Y coordinate detection, the light source controller 145 of the light source driver 14 shown in FIG. As shown in FIG. 5C, the amount of light emitted from the position detection light source 12 from the one side Y1 in the Y-axis direction toward the other side Y2 among the plurality of position detection light sources 12 is controlled. Reduce. At this time, the light emission amounts of the position detection light sources 12 arranged in the X-axis direction are equal. The relationship between the light emission amounts is as follows in the position detection light source 12 (position detection light sources 12aa, 12ab... 12fe, 12ff) shown in FIG. 4: 12aa>12ba>12ca>12da>12ea> 12fa
12aa = 12ab = 12ac = 12ad = 12ae = 12af
12ba = 12bb = 12bc = 12bd = 12be = 12bf
12ca = 12cb = 12cc = 12cd = 12ce = 12cf
12da = 12db = 12dc = 12dd = 12de = 12df
12ea = 12eb = 12ec = 12ed = 12ee = 12ef
12fa = 12fb = 12fc = 12fd = 12fe = 12ff
It is represented by

  As a result, the first intensity distribution L2Ya for Y coordinate detection in which the intensity of the position detection light L2 monotonously decreases from one side Y1 in the Y-axis direction toward the other side Y2 (second coordinate detection intensity distribution / second coordinate detection use). A first intensity distribution) is formed. In the first intensity distribution L2Ya for Y coordinate detection of this embodiment, the intensity of the position detection light L2 continuously decreases substantially linearly from one side Y1 in the Y-axis direction toward the other side Y2. In the first intensity distribution for Y-coordinate detection L2Ya, the position in the Y-axis direction and the intensity of the position detection light L2 have a certain relationship. For this reason, the amount of light reflected by the target object Ob and detected by the photodetector 30 is proportional to the intensity of the position detection light L2 in the first intensity distribution L2Ya for Y coordinate detection, and is defined by the position of the target object Ob. Value.

  Next, in the second period for Y-coordinate detection, the light source controller 145 of the light source driver 14 shown in FIG. 2 controls the position detection light source 12 via the drive circuit 140, as shown in FIG. On the other hand, contrary to the first period for Y-coordinate detection, among the plurality of position detection light sources 12, the amount of light emitted from the position detection light source 12 is reduced from the other side Y2 in the Y-axis direction toward the one side Y1. . At this time, the light emission amounts of the position detection light sources 12 arranged in the X-axis direction are equal. As a result, the Y coordinate detection second intensity distribution L2Yb (the second coordinate detection intensity distribution / second coordinate detection use) in which the intensity of the position detection light L2 monotonously decreases from the other side Y2 in the Y-axis direction toward the one side Y. A second intensity distribution) is formed. In the second intensity distribution L2Yb for Y coordinate detection of this embodiment, the intensity of the position detection light L2 continuously decreases substantially linearly from the other side Y2 in the Y-axis direction toward the one side Y1. In the second intensity distribution L2Yb for Y coordinate detection, the position in the Y-axis direction and the intensity of the position detection light L2 have a certain relationship. For this reason, the amount of light reflected by the target object Ob and detected by the photodetector 30 is proportional to the intensity of the position detection light L2 in the second intensity distribution L2Yb for Y coordinate detection, and is defined by the position of the target object Ob. Value.

  Therefore, the difference or ratio between the light amount detected by the photodetector 30 in the first period for Y coordinate detection and the light amount detected by the photodetector 30 in the second period for Y coordinate detection is the position of the target object Ob. Is a value defined by. Therefore, the Y-coordinate detection unit 52 of the position detection unit 50 uses the detection result of the photodetector 30 in the first period for Y-coordinate detection and the detection result of the photodetector 30 in the second period for Y-coordinate detection. Based on this, the Y coordinate of the target object Ob can be detected.

(Z coordinate detection operation)
In order to detect the Z coordinate of the target object Ob in the detection area 10R in the display device 100 with a position detection function of the present embodiment, the position detection light source 12 (position detection light sources 12aa, 12ab... 12fe, 12ff) are all turned on. As a result, a Z-coordinate detection intensity distribution is formed in which the intensity of the position detection light L2 monotonously decreases in a direction away from the screen member 8 in the Z-axis direction. In such a Z-coordinate detection intensity distribution, the position in the Z-axis direction and the intensity of the position detection light L2 have a certain relationship. Therefore, the amount of light reflected by the target object Ob and detected by the photodetector 30 is proportional to the intensity of the position detection light L2 in the Z coordinate detection intensity distribution, and is a value defined by the position of the target object Ob. . Therefore, the Z coordinate detection unit 53 of the position detection unit 50 can detect the Z coordinate of the target object Ob based on the detection result of the photodetector 30 in the Z coordinate detection period.

(Main effects of this form)
As described above, in the display device 100 with a position detection function according to the present embodiment, when the position detection light source 12 emits the position detection light L2, the position detection light L2 passes through the screen member 8 and moves toward the screen surface 8a. An intensity distribution of the position detection light L2 is formed. Therefore, when the position detection light L2 is reflected by the target object Ob located on the screen surface 8a side, the light is detected by the photodetector 30. Therefore, if the relationship between the position on the screen surface 8a side and the intensity of the position detection light L2 is known in advance, the position of the target object Ob can be detected based on the light reception result of the photodetector 30. Further, since the position detection light L2 is infrared light, visual recognition of an image formed on the screen member is not hindered by the position detection light L2.

  The screen member 8 includes a light shielding layer 80 on the back surface 8b, and the light shielding layer 80 is formed with a plurality of light transmitting portions 81 that allow the position detection light L2 to pass therethrough. For this reason, since the position detection light L2 emitted from the position detection light source 12 passes through the screen member 8 efficiently, the intensity distribution of the position detection light L2 can be reliably formed at a high level on the screen surface 8a side. Therefore, the position of the target object Ob can be reliably detected.

  Further, the light source driving unit 14 makes the X-coordinate detection intensity distribution (X-coordinate detection use) opposite to each other by making the light emission amount different between the position detection light sources 12 provided at positions shifted in the X-axis direction. Since the first intensity distribution L2Xa and the second intensity distribution L2Xb for X coordinate detection are formed, the X coordinate of the target object Ob can be reliably detected. Further, the light source drive unit 14 makes the Y coordinate detection intensity distributions (Y coordinate detection directions) opposite to each other by making the light emission amount different between the position detection light sources 12 provided at positions shifted in the Y axis direction. Since the first intensity distribution L2Ya and the second intensity distribution L2Yb for Y coordinate detection are formed, the Y coordinate of the target object Ob can be reliably detected.

  Further, since the light detector 30 faces the light receiving unit 31 in the direction along the screen surface 8a, the distance from the screen surface 8a that can detect the target object Ob is limited. Therefore, only the detection result of the target object Ob at a position close to the screen surface 8a can be detected as information, and the detection result of the target object Ob at a position away from the screen surface 8a is not detected as information. Therefore, no information is erroneously input by the target object Ob away from the screen surface 8a.

[Modification of Embodiment 1]
In the first embodiment, the light shielding layer 80 is formed on the screen member 8. However, the second embodiment may be applied when the light shielding layer 80 is not formed on the screen member 8. .

[Embodiment 2]
(overall structure)
Since the basic configuration of the present embodiment is the same as that of the first embodiment, common portions will be described with the same reference numerals. The overall configuration of the display device with a position detection function 100 according to this embodiment will be described with reference to FIGS.

  As shown in FIGS. 1A and 1B, the display device 100 with a position detection function according to the present embodiment is also provided with an image projection device 200 and a screen member 8 as in the first embodiment. It is. The display device with a position detection function 100 according to the present embodiment also includes an optical position detection device 10 as in the first embodiment. The optical position detection device 10 is different from the screen surface 8a side of the screen member 8. A plurality of position detection light sources 12 having light emitting portions directed to the screen member 8 on the opposite back surface side 8b, and a photodetector 30 having the light receiving portion 31 directed to the detection region 10R on the screen surface 8a side are provided. Therefore, when the position detection light source 12 emits the position detection light L2 from the light emitting portion toward the screen member 8, the position detection light L2 passes through the screen member 8 and forms an intensity distribution described later on the screen surface 8a side. To do.

  Also in the present embodiment, as in the first embodiment, the photodetector 30 includes a light receiving element such as a photodiode or a phototransistor, and on the screen surface 8a side of the screen member 8, the screen surface 8a outside the detection region 10R. The light receiving unit 31 is directed in the direction along the line. The position detection light source 12 includes a light emitting diode or the like, and emits position detection light L2 as diverging light. The position detection light L2 emits infrared light having a peak wavelength in a wavelength region near 850 nm. The screen member 8 includes a white screen 85 on the screen surface 8 a side, and includes a black light shielding layer 80 on the back surface side 8 b of the screen 85. The light shielding layer 80 is formed with a plurality of light transmitting portions 81 formed of holes, and each of the plurality of position detection light sources 12 has the light emitting portion directed toward the light transmitting portion 81. For this reason, when the position detection light source 12 emits the position detection light L2 from the light emitting portion toward the screen member 8, the position detection light L2 passes through the screen member 8 and forms an intensity distribution on the screen surface 8a side. It will be.

  As shown in FIG. 2, also in the display device with a position detection function 100 according to the present embodiment, as in the first embodiment, the optical position detection device 10 drives the light sources for driving each of the plurality of position detection light sources 12. And a position detector 50 that detects the position of the target object Ob based on the detection result of the photodetector 30. The light source drive unit 14 includes a drive circuit 140 corresponding to each of the plurality of position detection light sources 12 and a light source control unit 145 that controls lighting of each of the plurality of position detection light sources 12 via the drive circuit 140. ing. The position detection unit 50 includes an X coordinate detection unit 51 that detects the X coordinate of the target object Ob, a Y coordinate detection unit 52 that detects the Y coordinate of the target object Ob, and a Z coordinate detection that detects the Z coordinate of the target object Ob. A portion 53 is provided. Also in this embodiment, the driving for the position detection light source 12 and the detection operation by the position detection unit 50 are performed in conjunction with each other.

  As shown in FIG. 6, when the intensity distribution of the position detection light L2 described with reference to FIG. 3 is formed in the display device with a position detection function 100 according to the present embodiment, the light shielding layer 80 of the screen member 8 is not transparent. A plurality of optical portions 81 are formed in the X-axis direction, and a plurality of rows are also formed in the Y-axis direction. In this embodiment, the translucent part 81 is formed in a matrix in the X-axis direction and the Y-axis direction as the translucent parts 81aa, 81ab... 81fe, 81ff.

  In addition, a plurality of position detection light sources 12 having a light emitting portion facing the light transmitting portion 81 are disposed on the back surface side 8 b of the screen member 8. In the present embodiment, the position detection light source 12 is matrixed in the X-axis direction and the Y-axis direction as the position detection light sources 12aa, 12ab... 12fe, 12ff so as to correspond to the light transmitting portion 81 in a one-to-one relationship. It is formed in a shape. For this reason, in the light source driving unit 14 shown in FIG. 2, a plurality of drive circuits 140 (in a one-to-one relationship with the plurality of position detection light sources 12 (position detection light sources 12aa, 12ab... 12fe, 12ff). Drive circuits 140aa, 140ab... 140fe, 140ff) are provided.

(Configuration for X coordinate detection)
With reference to FIGS. 6 and 7, the configuration and operation for detecting the position of the target object Ob in the detection region 10 </ b> R in the display device 100 with a position detection function of the present embodiment will be described. FIG. 6 is an explanatory diagram showing the configuration of the light transmitting portion 81 of the screen member 8 and the position detection light source 12 in the display device with a position detection function 100 according to the second embodiment of the present invention. FIG. 7 is an explanatory view showing a state in which the intensity distribution of the position detection light L2 is formed in the display device with a position detection function 100 according to the second embodiment of the present invention. FIGS. FIG. 7C is an explanatory diagram of an X-coordinate detection intensity distribution when detecting the X-coordinate of the target object Ob, and FIGS. 7C and 7D are Y-coordinate detection intensity when detecting the Y-coordinate of the target object Ob. It is explanatory drawing of distribution. 6 and 7, the translucent portion 81 is indicated by a solid circle, and the position detection light source 12 is indicated by a dotted square. 6 and FIG. 7, the transparent portion 81 is indicated by a circle having a different size, and the size of the circle indicates the relative size (relative light transmission amount) of the transparent portion 81. ing. In FIG. 7, the position detection light source 12 in the extinguished state is hatched.

  In forming the intensity distribution of the position detection light L2 described with reference to FIG. 3 in the display device with a position detection function 100 according to this embodiment, in this embodiment, as shown in FIG. 6, the light shielding layer 80 of the screen member 8 is used. The light-transmitting portions 81 are formed in a plurality of rows in the X-axis direction, and a plurality of rows are also formed in the Y-axis direction. In this embodiment, the translucent part 81 is formed in a matrix in the X-axis direction and the Y-axis direction as the translucent parts 81aa, 81ab... 81fe, 81ff.

  In addition, a plurality of position detection light sources 12 having a light emitting portion facing the light transmitting portion 81 are disposed on the back surface side 8 b of the screen member 8. In the present embodiment, the position detection light source 12 is matrixed in the X-axis direction and the Y-axis direction as the position detection light sources 12aa, 12ab... 12fe, 12ff so as to correspond to the light transmitting portion 81 in a one-to-one relationship. It is formed in a shape. For this reason, in the light source driving unit 14 shown in FIG. 2, a plurality of drive circuits 140 (in a one-to-one relationship with the plurality of position detection light sources 12 (position detection light sources 12aa, 12ab... 12fe, 12ff). Drive circuits 140aa, 140ab... 140fe, 140ff) are provided.

As shown in FIG. 6, in this embodiment, the plurality of translucent portions 81 include those having different sizes, and in this embodiment, in order to form an X coordinate detection intensity distribution, In the translucent parts 81ab, 81ad, 81af arranged every other line, the size has the following relationship 81ab>81ad> 81af
It has become. Further, the translucent portions 81ab, 81ad, 81af and the translucent portions 81 arranged in every other row in the Y-axis direction with respect to the translucent portions 81ab, 81ad, 81af have the following relationship in size: 81ab = 81cb = 81eb
81ad = 81cd = 81ed
81af = 81cf = 81ef
It has become.

On the other hand, in the translucent part 81 adjacent to the translucent part 81 in the Y-axis direction, the size is opposite to the above, and the relationship is 81aa>81ac> 81ae.
81aa = 81ca = 81ea
81ac = 81cc = 81ec
81ae = 81ce = 81ee
It has become.

  In this embodiment, these translucent parts 81 are used as the first group of translucent parts 81 for X coordinate detection, and the position detection light source 12 with the light emitting part directed to these translucent parts 81 is the X coordinate detection first light source. A group of position detection light sources 12 is used.

  More specifically, in order to detect the X coordinate of the target object Ob in the detection region 10R, first, in the first period for X coordinate detection, the light source controller 145 of the light source driver 14 shown in FIG. As shown in FIG. 7A, the position detection light sources 12ab, 12cb, 12eb, 12ad, 12cd, and 12ed among the position detection light sources 12 of the first group are controlled. , 12af, 12cf, and 12ef are turned on, and the other position detection light sources 12 are turned off. Here, the translucent part 81 formed at a position shifted in the X-axis direction is different in size, so that the intensity of the position detection light L2 monotonously decreases from one side X1 to the other side X2 in the X-axis direction. A coordinate detection first intensity distribution L2Xa (first coordinate detection intensity distribution / first coordinate detection first intensity distribution) is formed. In the first intensity distribution L2Xa for X coordinate detection of this embodiment, the intensity of the position detection light L2 continuously decreases substantially linearly from the one side X1 in the X axis direction toward the other side X2. In the first X coordinate detection first intensity distribution L2Xa, the position in the X-axis direction and the intensity of the position detection light L2 have a certain relationship. For this reason, the amount of light reflected by the target object Ob and detected by the light detector 30 is proportional to the intensity of the position detection light L2 in the first X-coordinate detection first intensity distribution L2Xa and is defined by the position of the target object Ob. Value.

  Next, in the second period for X-coordinate detection, the light source controller 145 of the light source driver 14 shown in FIG. 2 controls the position detection light source 12 via the drive circuit 140, as shown in FIG. 7B. On the other hand, contrary to the first period for X coordinate detection, among the position detection light sources 12 of the first group, the position detection light sources 12aa, 12ca, 12ea, 12ac, 12cc, 12ec, 12ae, 12ce, 12ee are turned on. The other position detection light sources 12 are turned off. Here, since the sizes of the translucent portions 81 formed at positions shifted in the X-axis direction are different, the intensity of the position detection light L2 monotonously decreases from the other side X2 in the X-axis direction toward the one side X1. A coordinate detection second intensity distribution L2Xb (first coordinate detection intensity distribution / first coordinate detection second intensity distribution) is formed. In the second intensity distribution L2Xb for X coordinate detection of this embodiment, the intensity of the position detection light L2 continuously decreases substantially linearly from the other side X2 in the X-axis direction toward the one side X1. In the X-coordinate detection second intensity distribution L2Xb, the position in the X-axis direction and the intensity of the position detection light L2 have a certain relationship. For this reason, the amount of light reflected by the target object Ob and detected by the photodetector 30 is proportional to the intensity of the position detection light L2 in the X coordinate detection second intensity distribution L2Xb and is defined by the position of the target object Ob. Value.

  Therefore, the difference or ratio between the light amount detected by the photodetector 30 in the first period for X coordinate detection and the light amount detected by the photodetector 30 in the second period for X coordinate detection is the position of the target object Ob. Is a value defined by. Therefore, the X coordinate detection unit 51 of the position detection unit 50 determines the detection result of the photodetector 30 in the first period for X coordinate detection and the detection result of the photodetector 30 in the second period for X coordinate detection. Based on this, the X coordinate of the target object Ob can be detected.

(Configuration for Y coordinate detection)
Further, in this embodiment, in the light transmitting portions 81ba, 81da, and 81fa arranged every other in the Y-axis direction, the size is the following relationship: 81ba>81da> 81fa
It has become. In addition, the translucent portions 81ba, 81da, 81fa and the translucent portions 81 arranged in every other row in the X-axis direction with respect to the translucent portions 81ba, 81da, 81fa have the following relationship in size: 81ba = 81bc = 81be
81da = 81dc = 81de
81fa = 81fc = 81fe
It has become.

On the other hand, in the translucent part 81 adjacent to the translucent part 81 in the X-axis direction, the size is opposite to the above, and the relationship of the following formula is 81bb <81db <81fb.
81bb = 81bd = 81bf
81db = 81dd = 81df
81fb = 81fd = 81ff
It has become.

  In the present embodiment, these translucent portions 81 are used as a second group of translucent portions 81 for Y coordinate detection, and the position detection light source 12 with the light emitting portion directed to these translucent portions 81 is used as a Y coordinate detection second portion. The Y coordinate is detected using the two groups of position detection light sources 12.

  More specifically, in order to detect the X coordinate of the target object Ob in the detection region 10R, first, in the first period for Y coordinate detection, the light source controller 145 of the light source driver 14 shown in FIG. The position detection light source 12 is controlled via 140, and as shown in FIG. 7C, among the position detection light sources 12 of the second group, the position detection light sources 12ba, 12bc, 12be, 12da, 12dc, 12de. , 12fa, 12fc, 12fe are turned on, and the other position detection light sources 12 are turned off. Here, since the sizes of the translucent portions 81 formed at positions shifted in the Y-axis direction are different, the intensity of the position detection light L2 monotonously decreases from one side Y1 to the other side Y2 in the Y-axis direction. A coordinate detection first intensity distribution L2Ya (second coordinate detection intensity distribution / second coordinate detection first intensity distribution) is formed. In the first intensity distribution L2Ya for Y coordinate detection of this embodiment, the intensity of the position detection light L2 continuously decreases substantially linearly from one side Y1 in the Y-axis direction toward the other side Y2. In the first intensity distribution for Y-coordinate detection L2Ya, the position in the Y-axis direction and the intensity of the position detection light L2 have a certain relationship. For this reason, the amount of light reflected by the target object Ob and detected by the photodetector 30 is proportional to the intensity of the position detection light L2 in the first intensity distribution L2Ya for Y coordinate detection, and is defined by the position of the target object Ob. Value.

  Next, in the second period for Y-coordinate detection, the light source controller 145 of the light source driver 14 shown in FIG. 2 controls the position detection light source 12 via the drive circuit 140, as shown in FIG. In contrast to the first period for Y-coordinate detection, among the position detection light sources 12 of the second group, the position detection light sources 12bb, 12bd, 12bf, 12db, 12dd, 12df, 12fb, 12fd, and 12ff are turned on. The other position detection light sources 12 are turned off. Here, since the sizes of the translucent portions 81 formed at positions shifted in the Y-axis direction are different, the intensity of the position detection light L2 monotonously decreases from the other side Y2 in the Y-axis direction toward the one side Y1. A coordinate detection second intensity distribution L2Yb (second coordinate detection intensity distribution / Y coordinate detection second intensity distribution) is formed. In the second intensity distribution L2Yb for Y coordinate detection of this embodiment, the intensity of the position detection light L2 continuously decreases substantially linearly from the other side Y2 in the Y-axis direction toward the one side Y1. In the second intensity distribution L2Yb for Y coordinate detection, the position in the Y-axis direction and the intensity of the position detection light L2 have a certain relationship. For this reason, the amount of light reflected by the target object Ob and detected by the photodetector 30 is proportional to the intensity of the position detection light L2 in the second intensity distribution L2Yb for Y coordinate detection, and is defined by the position of the target object Ob. Value.

  Therefore, the difference or ratio between the light amount detected by the photodetector 30 in the first period for Y coordinate detection and the light amount detected by the photodetector 30 in the second period for Y coordinate detection is the position of the target object Ob. Is a value defined by. Therefore, the Y-coordinate detection unit 52 of the position detection unit 50 uses the detection result of the photodetector 30 in the first period for Y-coordinate detection and the detection result of the photodetector 30 in the second period for Y-coordinate detection. Based on this, the Y coordinate of the target object Ob can be detected.

(Z coordinate detection operation)
In the display device with a position detection function 100 according to the present embodiment, in order to detect the Z coordinate of the target object Ob in the detection region 10R, the position detection light source 12 (position detection light sources 12aa, 12ab... 12fe, 12ff) are all turned on. As a result, a Z-coordinate detection intensity distribution is formed in which the intensity of the position detection light L2 monotonously decreases in a direction away from the screen member 8 in the Z-axis direction. In such a Z-coordinate detection intensity distribution, the position in the Z-axis direction and the intensity of the position detection light L2 have a certain relationship. Therefore, the amount of light reflected by the target object Ob and detected by the photodetector 30 is proportional to the intensity of the position detection light L2 in the Z coordinate detection intensity distribution, and is a value defined by the position of the target object Ob. . Therefore, the Z coordinate detection unit 53 of the position detection unit 50 can detect the Z coordinate of the target object Ob based on the detection result of the photodetector 30 in the Z coordinate detection period.

(Main effects of this form)
As described above, also in the display device with a position detection function 100 according to the present embodiment, when the position detection light L2 is reflected by the target object Ob positioned on the screen surface 8a side, the light is detected as in the first embodiment. Detected by the instrument 30. Therefore, if the relationship between the position on the screen surface 8a side and the intensity of the position detection light L2 is known in advance, the position of the target object Ob can be detected based on the light reception result of the photodetector 30. Further, since the position detection light L2 is infrared light, visual recognition of an image formed on the screen member is not hindered by the position detection light L2. The screen member 8 includes a light shielding layer 80 on the back surface 8b, and the light shielding layer 80 is formed with a plurality of light transmitting portions 81 that allow the position detection light L2 to pass therethrough. For this reason, since the position detection light L2 emitted from the position detection light source 12 passes through the screen member 8 efficiently, the intensity distribution of the position detection light L2 can be reliably formed at a high level on the screen surface 8a side. Therefore, the position of the target object Ob can be reliably detected.

  Further, in the screen member 8, the size (translucent light amount) of the translucent portion 81 is made different in the X-axis direction and the Y-axis direction. Intensity distribution (first intensity distribution L2Xa for X coordinate detection and second intensity distribution L2Xb for X coordinate detection), and intensity distribution for Y coordinate detection (first intensity distribution L2Ya for Y coordinate detection and second intensity distribution for Y coordinate detection) L2Yb) can be formed. Therefore, the XY coordinates of the target object Ob can be reliably detected.

[Improvement of Embodiment 2]
In the second embodiment, the intensity distribution is formed according to the combination of the position detection light sources 12 to be turned on by the plurality of position detection light sources 12 and the size of the light transmitting portion 81, but in the plurality of position detection light sources 12 to be turned on. The amount of light emission may be different. Specifically, in the position detection light source 12 that is turned on when forming the X coordinate detection intensity distribution, the light emission amount is made different between the position detection light sources 12 provided at positions shifted in the X-axis direction, In the position detection light source 12 that is turned on when forming the Y coordinate detection intensity distribution, the light emission amount may be different between the position detection light sources 12 provided at positions shifted in the Y-axis direction. According to such a configuration, correction such as making the intensity distribution of the position detection light L2 more linear can be performed.

  In addition, when the X-coordinate detection intensity distribution is formed by turning on the first group of position detection light sources 12, a part of the second group of position detection light sources 12 may be turned on. When the detection light source 12 is turned on to form the Y coordinate detection intensity distribution, a part of the first group of position detection light sources 12 may be turned on. According to such a configuration, correction such as making the intensity distribution of the position detection light L2 more linear can be performed.

[Embodiment 3]
FIG. 8 is an explanatory view schematically showing a configuration of the display device 100 with a position detection function according to Embodiment 3 of the present invention. FIGS. 8A and 8B are diagrams showing the display device 100 with a position detection function. It is explanatory drawing which shows typically a mode that the principal part of this was seen from diagonally upward, and explanatory drawing which shows a mode that it looked at from the horizontal direction. Since the basic configuration of this embodiment is the same as that of Embodiments 1 and 2, common portions are denoted by the same reference numerals and description thereof is omitted.

  In the first and second embodiments, the light detector 30 faces the light receiving unit 31 in the direction along the screen surface 8a outside the detection region 10R on the screen surface 8a side of the screen member 8. FIG. As shown, in the present embodiment, the light detector 30 has the light receiving portion 31 facing the screen surface 8a from the out-of-plane direction of the screen surface 8a. More specifically, the photodetector 30 is provided on the front surface portion 201 of the housing 250 of the image projection apparatus 200. For this reason, the photodetector 30 detects the position detection light L3 reflected toward the image projection apparatus 200 by the target object Ob in the position detection light L2.

  Therefore, in the display device 100 with a position detection function according to the present embodiment, the distance from the screen surface 8a that can detect the target object Ob can be increased. Further, it is not necessary to install the photodetector 30 separately from the image projection apparatus 200. Further, processing for detecting the position of the target object Ob can be performed on the image projection apparatus 200 side. Furthermore, it is easy to reflect the position detection result of the target object Ob on the image projected from the image projection apparatus 200.

[Other embodiments]
In the above-described embodiment, the position detection light source 12 and the translucent part 81 are aligned in the X-axis direction and the Y-axis direction. However, the position detection light source 12 and the translucent part 81 are inclined in the X-axis direction and the Y-axis direction. For example, the layout of the position detection light source 12 and the light transmitting portion 81 may be changed as necessary. Further, the number of the position detecting light sources 12 and the light transmitting portions 81 may be set to optimum values according to the size of the screen member 8 and the like.

  The above embodiment is an example in which the present invention is applied to a projection display device. However, the present invention may be applied to detect the position of the target object Ob on the screen surface side of the screen member of the electronic blackboard.

8. Screen member, 8a, Screen surface, 10R, Detection area, 12, Light source for position detection, 30, Light detector, 51, Position detection unit, 100, Display device with position detection function, 200 ... Image projection device, 80 ... Light shielding layer, 81 ... Translucent part, 85 ... Screen, Ob ... Object object

Claims (12)

A display device with a position detection function for detecting a position of a target object located on a screen surface side where an image is visually recognized on a screen member by position detection light reflected by the target object,
The screen member has translucency with respect to the position detection light,
A light emitting part is directed to the screen member on the back side opposite to the screen surface side of the screen member, and position detection light is emitted from the light emitting part to form an intensity distribution of the position detection light on the screen surface side. A plurality of position detection light sources,
A light source driving unit for driving the position detection light source;
A photodetector for detecting the position detection light reflected by the target object located on the screen surface side;
A display device with a position detection function.   The display device with a position detection function according to claim 1, wherein the position detection light is infrared light. The screen member includes a light shielding layer on the back side,
The light shielding layer is formed with a plurality of light transmitting portions that allow the position detection light to pass through.
The display device with a position detection function according to claim 1, wherein the light source for position detection has the light emitting portion directed toward the light transmitting portion.   The light source driving unit controls lighting of each of the plurality of position detection light sources, and as the intensity distribution, a first coordinate detection intensity distribution whose intensity changes in a first direction along the screen surface, and 4. The position detection function according to claim 3, wherein the second coordinate detection intensity distribution intersecting with the first direction and changing in intensity in the second direction along the screen surface is formed with different timings. Display device.   The light source driving unit, as the first coordinate detection intensity distribution, a first coordinate detection first intensity distribution in which the intensity of the position detection light decreases from one side of the first direction to the other side, A first coordinate detection second intensity distribution in which the intensity of the position detection light decreases from the other side of the first direction toward the one side at different timings. As the second coordinate detection intensity distribution, A first intensity distribution for second coordinate detection in which the intensity of the position detection light decreases from one side in the two directions toward the other side, and the intensity of the position detection light from the other side in the second direction toward the one side. 5. The display device with a position detection function according to claim 4, wherein the second intensity distribution for detecting the second coordinate for which the lowering is generated is formed at different timings.   When the light source driving unit forms the first coordinate detection intensity distribution, the light source driving unit makes the light emission amount different between the position detection light sources provided at positions shifted in the first direction, and detects the second coordinate detection. 6. The position detection function according to claim 4, wherein a light emission amount is made different between the position detection light sources provided at positions shifted in the second direction when forming an intensity distribution for use. Display device. The light shielding layer includes a plurality of translucent portions, a first group of translucent portions having different light transmittance in the first direction, and a second group of translucent portions having different light amounts in the second direction. An optical part is formed,
When the light source driving unit forms the first coordinate detection intensity distribution, the light source driving unit turns on the position detection light source that directs the light emitting unit to the light transmitting unit of the first group, and the second coordinate detection intensity distribution. 6. The display device with a position detection function according to claim 4, wherein the position detection light source that directs the light-emitting portion to the light-transmitting portion of the second group is turned on.   When the light source driving unit forms the first coordinate detection intensity distribution, the light source driving unit makes the light emission amount different between the position detection light sources provided at positions shifted in the first direction, and detects the second coordinate detection. The display device with a position detection function according to claim 7, wherein, when forming an intensity distribution, a light emission amount is made different between the position detection light sources provided at positions shifted in the second direction. .   The display device with a position detection function according to claim 1, further comprising an image projection device that projects an image toward the screen surface.   The display device with a position detection function according to claim 1, wherein the light detector has a light receiving portion directed in a direction along the screen surface.   10. The display device with a position detection function according to claim 1, wherein the light detector has a light receiving portion directed toward the screen surface from an out-of-plane direction of the screen surface.   The display device with a position detection function according to claim 9, wherein the photodetector is mounted on an image projection device.