JP2012108018A - Optical position detection device, and apparatus with position detection function - Google Patents

Abstract

To provide an optical position detection device and a device with a position detection function capable of forming a light intensity distribution whose intensity appropriately changes monotonously in a detection target space even when using a light guide plate. .
In an optical position detection device, a light source rotator 13 emits detection light L2 emitted from a detection light source 12 to a detection target space 10R. In the light source rotator 13, the first light guides 13 </ b> A and 13 </ b> C emit light whose intensity increases monotonously from one end to the other end, whereas the second light guides 13 </ b> B and 13 </ b> D. Opposite to the first light guide portions 13A and 13C, emits light whose intensity decreases monotonously from one end portion to the other end portion. Therefore, the position of the target object Ob is detected by using the light reception result of the light detector 30 when the light source rotator 13 rotates and the first light guide portions 13A and 13C arrive at the predetermined angular positions. be able to.
[Selection] Figure 1

Description

  The present invention relates to an optical position detection device that optically detects the position of a target object, and a device with a position detection function that includes the optical position detection device.

  As an optical position detection device that optically detects a target object, for example, detection light is emitted from each of a plurality of light sources for detection toward the target object via a light guide plate, and the detection light reflected by the target object is used. What is detected by a photodetector has been proposed. In the optical position detection device having such a configuration, the position of the target object is detected based on the detection result of the detection light by the photodetector (see, for example, Patent Documents 1 and 2).

JP 2010-127671 A JP 2009-295318 A

  However, in this type of optical position detection device, the intensity monotonously increases from one side to the other side by emitting detection light emitted from a plurality of light sources for detection through a common light guide plate. A first intensity distribution and a second intensity distribution in which the intensity monotonously decreases from the other side to the one side are formed, and the detection result and the second intensity distribution at the photodetector when the first intensity distribution is formed are The position of the target object is detected based on the detection result of the photodetector at the time of formation.

  However, in the configuration in which the intensity distribution is monotonously changed in the reverse direction by the common light guide plate as in the inventions described in Patent Documents 1 and 2, problems such as design problems of the light guide plate and directivity of the light source Due to the influence, there is a problem that an appropriate intensity distribution cannot be formed.

  In view of the above problems, an object of the present invention is to provide an optical position detection device that can form a light intensity distribution in which the intensity appropriately changes monotonously in the detection target space even when the light guide plate is used. Another object of the present invention is to provide a device with a position detection function including such an optical position detection device.

  In order to solve the above-described problems, the present invention is an optical position detection device that optically detects the position of a target object, and includes a detection light source that emits detection light, and a detection emitted from the detection light source. Light is emitted from the light source for detection and the first light guide part that emits light as light whose intensity increases monotonously from the one side end part to the other side end part of the light emitting part. A light source that takes the detection light into the light incident part and emits the second light guide part as light whose intensity decreases monotonously from one side end part to the other side end part of the light emission part at different angular positions. A rotating body for light, a photodetector for receiving the detection light reflected by a target object located in a space on the emission side of the detection light from the rotating body for light source, and based on a light reception result by the light detector A position detection unit for detecting the position of the target object. It is characterized in.

  The optical position detection device according to the present invention includes a light source rotating body including a first light guide unit and a second light guide unit at different angular positions, and the first light guide unit is formed from one end portion. In contrast to the first light guide part, the second light guide part emits light whose intensity increases monotonously toward the other side end part, and from the one side end part to the other side end part. The light whose intensity decreases monotonously is emitted. Therefore, when the light source rotator rotates and the first light guide section arrives at the predetermined angular position, the light reception result at the photodetector, and when the second light guide section arrives at the predetermined angular position. The position of the target object can be detected by using the light reception result by the photodetector. Here, the first light guide portion has a function of emitting light whose intensity increases monotonously from one end portion to the other end portion, and the second light guide portion is opposite to the first light guide portion. The function of emitting light whose intensity monotonously decreases from one end to the other end. Accordingly, each of the first light guide and the second light guide has only to have a single emission characteristic, and therefore, in the method using the light guide plate, an intensity distribution in which the intensity appropriately changes monotonously can be formed. it can. Therefore, according to the present invention, the position of the target object can be detected with high accuracy.

  In the present invention, the light source for detection is provided as a first light source for detection and a second light source for detection that rotate integrally with the rotating body for light source, and the first light source for detection is provided in the first light guide unit. A configuration may be employed in which the detection light is emitted toward the light incident portion, and the second light source for detection emits the detection light toward the light incident portion of the second light guide portion.

  In this case, the detection light emitted from the first light source for detection is directly incident on a light incident portion of the first light guide unit, and the detection light emitted from the second light source for detection is directly The structure which injects into the light-incidence part of a 2nd light guide part is employable.

  In the present invention, a first auxiliary light guide that guides the detection light emitted from the first light source for detection to a light incident portion of the first light guide, and the light emitted from the second light source for detection. A configuration including a second auxiliary light guide that guides detection light to the light incident portion of the second light guide can be employed.

  In the present invention, the detection light source is fixed, and light emitted from the detection light source is incident on a light incident portion of the first light guide portion by rotation of the light source rotator. A configuration that switches to the second state of entering the light incident part of the second light guide part may be adopted.

  In this case, the detection light emitted from the light source for detection directly enters the light incident portion of the first light guide portion in the first state, and the light of the second light guide portion in the second state. A configuration in which the light is directly incident on the incident portion can be employed.

  Further, the detection light emitted from the detection light source is guided to the light incident portion of the first light guide portion in the first state, and to the light incident portion of the second light guide portion in the second state. You may employ | adopt the structure provided with the auxiliary | assistant light guide part to guide.

  In addition, the configuration includes an auxiliary light guide unit that distributes the detection light emitted from the light source for detection and guides the detection light to the light incident unit of the first light guide unit and the light incident unit of the second light guide unit. It may be adopted.

  In the present invention, there is provided a reference light source that causes reference light to enter the photodetector without passing through the exit-side space, and the position detector detects the detection intensity so that the received light intensity at the photodetector is equal. A configuration may be employed in which the position of the target object is detected based on the result of driving the light source for reference and the light source for reference.

  The optical position detection device according to the present invention can be used in a device with a position detection function. Such a device with a position detection function includes a direct-view or projection-type display device with a position detection function, a screen device with a position detection function having a screen on which information is visually recognized, a show window with a position detection function, an amusement with a position detection function Equipment etc. can be mentioned.

It is explanatory drawing which shows typically the whole structure of the optical position detection apparatus which concerns on Embodiment 1 of this invention. It is explanatory drawing which shows layout, such as a light guide part of the optical position detection apparatus which concerns on Embodiment 1 of this invention. It is explanatory drawing which shows a mode that the light source for a detection is lighted one by one while rotating the rotating body for light sources in the optical position detection apparatus which concerns on Embodiment 1 of this invention, and light intensity distribution is formed. It is explanatory drawing which shows typically the principle of the optical position detection apparatus which concerns on Embodiment 1 of this invention. It is explanatory drawing which shows typically the principal part of the optical position detection apparatus which concerns on the modification of Embodiment 1 of this invention. It is explanatory drawing which shows typically the principal part of the optical position detection apparatus which concerns on Embodiment 2 of this invention. It is explanatory drawing which shows typically the principal part of the optical position detection apparatus which concerns on the modification of Embodiment 2 of this invention. It is explanatory drawing which shows typically the principal part of the optical position detection apparatus which concerns on Embodiment 3 of this invention. It is explanatory drawing which shows the principal part of the optical position detection apparatus which concerns on Embodiment 4 of this invention. It is explanatory drawing of the screen apparatus with a position detection function (apparatus with a position detection function) to which this invention is applied. It is explanatory drawing of the projection type display apparatus (apparatus with a position detection function) with a position detection function to which this invention is applied.

  Next, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, the axes that intersect each other are referred to as the X axis and the Y axis, and the axes that intersect the X axis and the Y axis are referred to as the Z axis. In the drawings referred to below, for convenience of explanation, the X-axis direction (first direction) is the horizontal direction, the Y-axis direction (second direction) is the vertical direction, and the Z-axis direction (third direction) is the detection light. It is expressed as a direction in which the detection light travels in the emission side space. 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 of the respective members are different from each other in order to make each member large enough to be recognized on the drawings.

[Embodiment 1 / Light source rotation]
(Overall configuration of optical position detector)
FIG. 1 is an explanatory diagram schematically showing the overall configuration of the optical position detection apparatus according to Embodiment 1 of the present invention. FIG. 2 is an explanatory diagram showing a layout of the light guide unit and the like of the optical position detection device according to Embodiment 1 of the present invention, and FIGS. 2A and 2B are planes showing the layout of the light guide plate. It is a figure and a side view.

  As shown in FIG. 1 and FIGS. 2A and 2B, the optical position detection device 10 of the present embodiment emits a plurality of detection light sources 12 that emit detection light L <b> 2 and the detection light sources 12. The light source rotator 13 that takes in and emits the detection light L2 and one of the detection light L3 reflected by the target object Ob in the space on the emission side (detection target space 10R) of the detection light L2 from the light source rotator 13 And a photodetector 30 for detecting the part.

  The light source rotator 13 is connected to an actuator 60 using a motor or the like, and can rotate intermittently around the axis via a central axis L extending in the Z-axis direction. The light source rotator 13 includes a plurality of light guides (first light guides 13A and 13C and second light guides 13B and 13D) in the circumferential direction, and the first light guides 13A and 13C. And the second light guide portions 13B and 13D are alternately provided in the circumferential direction. Each of the first light guide portions 13A and 13C and the second light guide portions 13B and 13D is a translucent plate-like member, and is provided at one end in the radial direction (the end near the center axis L). , A light incident part 131 for taking in the detection light L2 emitted from the detection light source 12 is provided. In addition, the first light source 12A, 12C and the second detection light source 12B are used as the detection light source 12 in the light incident portions 131 of the first light guide units 13A, 13C and the second light guide units 13B, 13D. In this embodiment, the first detection light sources 12A and 12C and the second detection light sources 12B and 12D are integrated with the first light guide portions 13A and 13C and the second light guide portions 13B and 13D. Can be rotated. Each of the detection light sources 12 is constituted by an LED (light emitting diode) or the like, and emits detection light L2 made of infrared light as diverging light. That is, since the detection light L2 preferably has a wavelength region that is efficiently reflected by the target object Ob such as a finger, the detection light L2 has a peak in the infrared region where the reflectance on the surface of the human body is high. For example, the detection light L2 is near infrared light close to the visible light region, for example, light having a peak near the wavelength of 850 nm.

  In the light source rotating body 13, the first light guide portions 13 </ b> A and 13 </ b> C and the second light guide portions 13 </ b> B and 13 </ b> D each include a light emitting portion 130 that is connected to the light incident portion 131 and faces the detection target space 10 </ b> R. The detection light L2 taken from the light incident part 131 can be emitted from the light emitting part 130 to the detection target space 10R.

  Among the first light guides 13A and 13C and the second light guides 13B and 13D, the first light guides 13A and 13C transmit the detection light L2 from one radial end to the other radial end. Is emitted as detection light L2a whose intensity monotonously increases toward the portion (end 132 on the side far from the central axis L). In this embodiment, the first light guides 13A and 13C emit the detection light L2 as detection light L2a whose intensity increases linearly monotonously from one radial end to the other radial end. . The first light intensity distribution L2Xa of the detection light L2a is shown as a one-dot chain line in FIG.

  In contrast, the second light guides 13B and 13D emit the detection light L2 as light L2b whose intensity monotonously decreases from one radial end to the other radial end. In the present embodiment, the second light guides 13B and 13D emit the detection light L2 as light L2b whose intensity linearly monotonously decreases from one radial end to the other radial end. The second light intensity distribution L2Xb of the detection light L2b is shown as a one-dot chain line in FIG.

  In giving the above characteristics to the first light guide parts 13A and 13C and the second light guide parts 13B and 13D, the light emission of the first light guide parts 13A and 13C and the second light guide parts 13B and 13D The part 130 or the back side is provided with a surface uneven structure, a prism structure, a scattering layer (not shown), etc., and is incident on the first light guide parts 13A and 13C and the second light guide parts 13B and 13D. The light propagating through the inside is gradually deflected and emitted from the light emitting unit 130 as it travels in the propagation direction. In addition, the light emitting sections 130 of the first light guide sections 13A and 13C and the second light guide sections 13B and 13D may include prism sheets or the like in order to equalize the detection lights L2a and L2b as necessary. An optical sheet such as a light scattering plate may be disposed.

  The photodetector 30 includes a light receiving element such as a photodiode or a phototransistor, and is fixed in a state where the light receiving unit faces the detection target space 10R.

  Furthermore, the optical position detection device 10 of the present embodiment includes a reference light source 12R that causes the reference light Lr to enter the photodetector 30 without passing through the detection target space 10R, and the reference light source 12R is detected. Like the light source 12, the LED emits near infrared light close to the visible light region, for example, light having a peak near the wavelength of 850 nm as divergent light. The reference light source 12R is in a fixed state like the photodetector 30. The reference light Lr emitted from the reference light source 12R is used as a reference for setting initial conditions of the first detection light sources 12A and 12C, the second detection light sources 12B and 12D, and the photodetector 30. it can. Further, when the position of the target object Ob is detected by the method described later, the detection intensity of the reference light Lr at the photodetector 30 and the detection intensity of the detection light L3 reflected by the target object Ob at the photodetector 30 are calculated. The result of comparison can be used.

  The optical position detection device 10 having such a configuration includes a light source drive unit 14 for driving the detection light source 12 (first detection light sources 12A and 12C and second detection light sources 12B and 12D) and the reference light source 12R, and a light source. For example, the light source driving unit 14 and the control unit 50 are configured in a common semiconductor integrated circuit. The control unit 50 includes a signal processing unit 55 that performs signal processing on the detection result of the photodetector 30, a rotation control unit 57 that controls the rotation of the light source rotator 13 by driving the actuator 60, and the photodetector 30. And a position detection unit 56 that detects the position of the target object Ob based on the detection result in FIG.

(Explanation of light intensity distribution)
FIG. 3 is an explanatory diagram showing a state in which a light intensity distribution is formed by sequentially turning on the detection light source 12 while rotating the light source rotator 13 in the optical position detection device 10 according to the first embodiment of the present invention. FIGS. 3A and 3B are explanatory views showing the angular position of the light source rotator 13 in the first period and explanatory views showing the angular position of the light source rotator 13 in the second period. .

  In the optical position detection apparatus 10 described with reference to FIGS. 1 and 2, the light source rotating body 13 rotates intermittently around the central axis L, and the detection light source 12 sequentially moves in synchronization with the rotation. Light. More specifically, as shown in FIG. 3A, when the light source rotating body 13 rotates around the central axis L and the first light guide portion 13A arrives at a position overlapping the detection target space 10R, the light source The rotation of the rotating body 13 is stopped for a predetermined period. During such a first period, the first detection light source 12A is turned on. As a result, since the detection light L2a is emitted from the first light guide 13A to the detection target space 10R during the first period, the detection target space 10R has a radial end on the other side end in the radial direction. A first light intensity distribution L2Xa in which the intensity linearly increases monotonously toward the part is formed. Meanwhile, among the plurality of detection light sources 12, the detection light sources 12 other than the first detection light source 12A are in the off state. The light source rotating body 13 rotates around the central axis L, and the first light guide portion 13C arrives at a position overlapping the detection target space 10R. Even when the light source 12 is turned off, it is the first period in which the first light intensity distribution L2Xa is formed in the detection target space 10R.

  Next, as illustrated in FIG. 3B, when the light source rotator 13 rotates around the central axis L and the second light guide unit 13B arrives at a position overlapping the detection target space 10 </ b> R, the light source rotator. The rotation of 13 stops for a predetermined period. During the second period, the second detection light source 12B is turned on. As a result, since the detection light L2b is emitted from the second light guide 13B to the detection target space 10R during the second period, the detection target space 10R has a radial end on the other side end in the radial direction. A second light intensity distribution L2Xb in which the intensity linearly monotonously decreases toward the portion is formed. Meanwhile, among the plurality of detection light sources 12, the detection light sources 12 other than the second detection light source 12B are in an extinguished state. The light source rotator 13 rotates around the central axis L, and the second light guide unit 13D arrives at a position overlapping the detection target space 10R, and the second detection light source 12D is turned on to perform other detection. Even when the light source 12 is turned off, it is the second period in which the second light intensity distribution L2Xb is formed in the detection target space 10R. Accordingly, as described below, in the first period and the second period, the position detection unit 56 detects the position of the target object Ob in the detection target space 10 </ b> R by using the detection results of the photodetector 30. can do.

(Basic principle of position detection)
In the optical position detection device 10 of the present embodiment, the light intensity distribution of the detection light L2 (first light intensity distribution L2Xa, second light intensity distribution L2Xb) is formed in the detection target space 10R and reflected by the target object Ob. The detection light L3 is detected by the photodetector 30, and the position detector 56 detects the position of the target object Ob in the detection target space 10R based on the detection result of the photodetector 30. Therefore, the principle of position detection will be described with reference to FIG. In acquiring the position information of the target object Ob in the detection target space 10R based on the detection result of the light detector 30, for example, a microprocessor unit (MPU) is used as the position detection unit 56, whereby a predetermined value is obtained. A configuration can be adopted in which processing is performed in accordance with execution of software (operation program). In addition, a configuration using hardware such as a logic circuit may be employed.

  FIGS. 4A and 4B are explanatory views schematically showing the principle of the optical position detection apparatus 10 according to Embodiment 1 of the present invention. FIGS. 4A and 4B show detection light reflected by the target object Ob. FIG. 5 is an explanatory diagram showing the intensity of the detection light, and an explanatory diagram showing how the light intensity distribution of the detection light L2 is adjusted so that the detection light L3 reflected by the target object Ob has the same intensity.

  In the optical position detection device 10 of the present embodiment, the position of the target object Ob using the first light intensity distribution L2Xa and the X second light intensity distribution L2Xb described with reference to FIGS. 3 (a) and 3 (b). (X-axis coordinate) is detected. More specifically, the detection intensity at the photodetector 30 in the state where the first light intensity distribution L2Xa is formed in the first period shown in FIG. 3A and the second intensity shown in FIG. 3B. Comparison is made with the detection intensity at the photodetector 30 in the state in which the two light intensity distribution L2Xb is formed, and the position of the target object Ob is detected by the method described below with reference to FIG.

  First, as shown in FIGS. 3A and 4A, the first light intensity distribution L2Xa and the second light intensity distribution L2Xb have the same absolute value in the first period and the second period, and the X-axis direction It is formed so as to be reversed. In this state, if the detection value LXa at the photodetector 30 in the first period is equal to the detection value LXb at the photodetector 30 in the second period, the target object Ob is positioned at the center in the X-axis direction. I understand.

  On the other hand, when the detection value LXa at the photodetector 30 in the first period is different from the detection value LXb at the photodetector 30 in the second period, the detection values LXa and LXb are equal. In addition, the control amount (drive current) for the detection light source 12 is adjusted, and as shown in FIG. 4B, the first light intensity distribution L2Xa is formed again in the first period, and the second in the second period. A light intensity distribution L2Xb is formed. Then, the detection value LXa at the photodetector 30 in the first period is made equal to the detection value LXb at the photodetector 30 in the second period. Depending on the ratio or difference between the control amount (current value) for the first detection light sources 12A and 12C and the control amount (current value) for the second detection light sources 12B and 12D when such differential is performed, the target object The X coordinate of Ob can be detected. Further, the ratio or difference between the control amount adjustment amount ΔLXa for the first detection light sources 12A and 12C in the first period and the control amount adjustment amount ΔLXb for the second detection light sources 12B and 12D in the second period, etc. Thus, the X coordinate of the target object Ob may be detected. According to such a method, even when ambient light other than the detection light L2, for example, an infrared component included in external light is incident on the photodetector 30, the detection values LXa and LXb are equal to the detection light source 12. When the control amount is adjusted, the intensity of the infrared component included in the ambient light is canceled out, so that the infrared component included in the ambient light does not affect the detection accuracy. For convenience of explanation, the detection value LXa in the photodetector 30 in the first period is directly compared with the detection value LXb in the photodetector 30 in the second period. By using the result of comparing the detection intensity of Lr and the detection intensity of the detection light L3 reflected by the target object Ob at the photodetector 30, it is possible to eliminate the influence of environmental light and the like.

(Main effects of this form)
As described above, the optical position detection device 10 of the present embodiment includes the light source rotating body 13 including the first light guide portions 13A and 13C and the second light guide portions 13B and 13D at different angular positions. The first light guides 13A and 13C emit light whose intensity increases monotonously from one end to the other end, whereas the second light guides 13B and 13D Contrary to the light portions 13A and 13C, light whose intensity monotonously decreases from one end portion to the other end portion is emitted. Accordingly, when the first light guides 13A and 13C arrive at the predetermined angular positions by the rotation of the light source rotator 13, the light reception results at the photodetector 30 and the second light guides 13B at the predetermined angular positions. , 13D can be used to detect the position of the target object Ob using the light reception result of the photodetector 30. Here, the first light guides 13A and 13C have a function of emitting light whose intensity increases monotonously from one end to the other end, and the second light guides 13B and 13D are the first guides. Contrary to the light portions 13A and 13C, the light portions 13A and 13C have a function of emitting light whose intensity monotonously decreases from one side end to the other side end. Accordingly, the first light guide parts 13A and 13C and the second light guide parts 13B and 13D only have to have a single emission characteristic, so that the intensity appropriately monotonously changes in the method using the light guide plate. A distribution can be formed. Therefore, according to this embodiment, the position of the target object Ob can be detected with high accuracy.

[Modification of First Embodiment / Light Source Rotation + Auxiliary Light Guide]
FIG. 5 is an explanatory view schematically showing a main part of the optical position detection device 10 according to a modification of the first embodiment of the present invention. FIGS. 5 (a) and 5 (b) show the first period. It is explanatory drawing which shows the angular position of the rotary body for light sources 13, and explanatory drawing which shows the angular position of the rotary body for light sources 13 in a 2nd period. Since the basic configuration of this embodiment is the same as that of Embodiment 1, common portions are denoted by the same reference numerals and description thereof is omitted.

  As shown in FIG. 5, the optical position detection device 10 of the present embodiment also has a plurality of detection light sources 12 that emit detection light L2 and the detection light L2 emitted from the detection light source 12, as in the first embodiment. Is detected and a part of the detection light L3 reflected by the target object Ob in the emission side space (detection target space 10R) of the detection light L2 from the light source rotation body 13 is detected. The light source rotator 13 is rotatable around the axis L0. The photodetector 30 and the reference light source 12R are in a fixed state.

  Also in the present embodiment, as in the first embodiment, the light source rotating body 13 includes a plurality of light guide sections (first light guide sections 13A and 13C and second light guide sections 13B and 13D) in the circumferential direction. The first light guides 13A and 13C and the second light guides 13B and 13D are alternately provided in the circumferential direction. Further, each of the first light guide portions 13A and 13C and the second light guide portions 13B and 13D is a translucent plate-like member, and has one end in the radial direction (the end on the side close to the central axis L). ) Is provided with a light incident portion 131 that takes in the detection light L2 emitted from the light source 12 for detection.

  Here, each of the first light guides 13A and 13C and the second light guides 13B and 13D includes a light incident part 131 on the side opposite to the side where the detection target space 10R is located. For 131, auxiliary light guide parts 133A, 133B, 133C, and 133D that rotate integrally with the first light guide parts 13A and 13C and the second light guide parts 13B and 13D are provided.

  Moreover, the light source 12 for a detection is provided in the edge part of auxiliary | assistant light guide part 133A, 133B, 133C, 133D. Therefore, the detection light L2 emitted from the first detection light sources 12A and 12C is incident on the first light guide portions 13A and 13C via the auxiliary light guide portions 133A and 133C, and the first light guide portions 13A and 13C. The light is emitted from the light emitting unit 130. In addition, the detection light L2 emitted from the second light sources for detection 12B and 12D enters the second light guides 13B and 13D via the auxiliary light guides 133B and 133D, and the second light guides 13B and 13D. The light is emitted from the light emitting unit 130.

  Here, the first light sources 12A and 12C and the second light sources 12B and 12D are the same as the auxiliary light guides 133A, 133B, 133C, and 133D, and the first light guides 13A and 13C and the second light guide. It can rotate integrally with the parts 13B and 13D.

  Therefore, as shown in FIG. 5A, during the first period when the light source rotator 13 rotates around the central axis L and the first light guide 13A arrives at a position overlapping the detection target space 10R, Since the first detection light source 12A is turned on and the detection light L2a is emitted from the first light guide portion 13A to the detection target space 10R, the detection target space 10R has a radial direction from one end in the radial direction to the other side in the radial direction. A first light intensity distribution L2Xa is formed in which the intensity linearly increases monotonously toward the end. The same applies to the first period when the first light guide portion 13C arrives at a position overlapping the detection target space 10R.

  Further, as shown in FIG. 5B, during the second period when the light source rotating body 13 rotates around the central axis L and the second light guide portion 13B arrives at a position overlapping the detection target space 10R, 2 Since the light source 12B for detection is turned on and the detection light L2b is emitted from the second light guide portion 13B to the detection target space 10R, the detection target space 10R has a radial direction from one end in the radial direction to the other side in the radial direction. A second light intensity distribution L2Xb is formed in which the intensity linearly monotonously decreases toward the end. The same applies to the second period when the second light guide unit 13D arrives at a position overlapping the detection target space 10R.

  For this reason, according to the present embodiment, the position of the target object Ob can be detected by using the light reception result of the photodetector 30 as in the first embodiment. The first light guides 13A and 13C have a function of emitting light whose intensity increases monotonously from one end to the other end, and the second light guides 13B and 13D are the first light guides. Contrary to the portions 13A and 13C, it has a function of emitting light whose intensity decreases monotonously from one end to the other end. Accordingly, the first light guide parts 13A and 13C and the second light guide parts 13B and 13D only have to have a single emission characteristic, so that the intensity appropriately monotonously changes in the method using the light guide plate. The same effects as those of the first embodiment can be obtained, such as being able to form a distribution.

  Further, in this embodiment, since the auxiliary light guides 133A, 133B, 133C, and 133D are used, the layout of each component is easy, such as the detection light source 12 need not be disposed near the central axis L.

[Embodiment 2 / Light source fixation]
FIGS. 6A and 6B are explanatory views schematically showing the main part of the optical position detection device 10 according to the second embodiment of the present invention. FIGS. 6A and 6B are diagrams illustrating the rotation for the light source in the first period. It is explanatory drawing which shows the angular position of the body 13, and explanatory drawing which shows the angular position of the rotary body 13 for light sources in a 2nd period. Since the basic configuration of this embodiment is the same as that of Embodiment 1, common portions are denoted by the same reference numerals and description thereof is omitted.

  As shown in FIG. 6, the optical position detection device 10 of the present embodiment also includes the detection light source 12 that emits the detection light L <b> 2 and the detection light L <b> 2 emitted from the detection light source 12, as in the first embodiment. Light for detecting a part of the detection light L3 reflected by the target object Ob in the emission side space (detection target space 10R) of the detection light L2 from the light source rotation body 13 The light source rotator 13 is rotatable about the axis L0. The photodetector 30 and the reference light source 12R are in a fixed state.

  Also in the present embodiment, as in the first embodiment, the light source rotating body 13 includes a plurality of light guide sections (first light guide sections 13A and 13C and second light guide sections 13B and 13D) in the circumferential direction. The first light guides 13A and 13C and the second light guides 13B and 13D are alternately provided in the circumferential direction. Further, each of the first light guide portions 13A and 13C and the second light guide portions 13B and 13D is a translucent plate-like member, and has one end in the radial direction (the end on the side close to the central axis L). ) Is provided with a light incident portion 131 that takes in the detection light L2 emitted from the light source 12 for detection.

  In this embodiment, the detection light source 12 is fixed in one place where the detection target space 10R is set. For this reason, in this embodiment, the detection light L2 emitted from the light source for detection 12 is guided to the light incident part 131 of the first light guide parts 13A and 13C, and the light of the second light guide parts 13B and 13D. Switching to the second state leading to the incident part 131 is performed. More specifically, as shown in FIG. 6A, the light source rotating body 13 rotates around the central axis L, and the first light guide portion 13A arrives at a position overlapping the detection target space 10R. During the period, the detection light source 12 and the light incident portion 131 of the first light guide portion 13A face each other. Therefore, since the detection light L2a is emitted from the first light guide portion 13A to the detection target space 10R, the detection target space 10R has an intensity from the one end portion in the radial direction toward the other end portion in the radial direction. A first light intensity distribution L2Xa that monotonously increases linearly is formed. The same applies to the first period when the first light guide portion 13C arrives at a position overlapping the detection target space 10R.

  Further, as shown in FIG. 6B, detection is performed during the second period in which the light source rotator 13 rotates around the central axis L and the second light guide 13B arrives at a position overlapping the detection target space 10R. The light source 12 for light and the light incident part 131 of the second light guide part 13B face each other. Accordingly, since the detection light L2b is emitted from the second light guide portion 13B to the detection target space 10R, the detection target space 10R has an intensity from one radial end to the other radial end. A second light intensity distribution L2Xb that monotonously decreases linearly is formed. The same applies to the second period when the second light guide unit 13D arrives at a position overlapping the detection target space 10R.

  Even in the optical position detection apparatus 10 configured as described above, the position of the target object Ob can be detected by using the light reception result of the photodetector 30 as in the first embodiment. The first light guides 13A and 13C have a function of emitting light whose intensity increases monotonously from one end to the other end, and the second light guides 13B and 13D are the first light guides. Contrary to the portions 13A and 13C, it has a function of emitting light whose intensity decreases monotonously from one end to the other end. Accordingly, the first light guide parts 13A and 13C and the second light guide parts 13B and 13D only have to have a single emission characteristic, so that the intensity appropriately monotonously changes in the method using the light guide plate. The same effects as those of the first embodiment can be obtained, such as being able to form a distribution.

  Further, in this embodiment, since the detection light source 12 is arranged in a fixed state, there is an effect that power supply to the detection light source 12 is easy.

[Modification of Embodiment 2 / Light Source Fixation + Auxiliary Light Guide]
FIG. 7 is an explanatory view schematically showing a main part of the optical position detection device 10 according to a modification of the second embodiment of the present invention. FIGS. 7 (a) and 7 (b) are views in the first period. It is explanatory drawing which shows the angular position of the rotary body for light sources 13, and explanatory drawing which shows the angular position of the rotary body for light sources 13 in a 2nd period. Since the basic configuration of this embodiment is the same as that of Embodiment 1, common portions are denoted by the same reference numerals and description thereof is omitted.

  As shown in FIG. 7, the optical position detection device 10 of this embodiment also includes the detection light source 12 that emits the detection light L2 and the detection light L2 emitted from the detection light source 12 in the same manner as in the first embodiment. Light for detecting a part of the detection light L3 reflected by the target object Ob in the emission side space (detection target space 10R) of the detection light L2 from the light source rotation body 13 The light source rotator 13 is rotatable about the axis L0. The photodetector 30 and the reference light source 12R are in a fixed state.

  Also in the present embodiment, as in the first embodiment, the light source rotating body 13 includes a plurality of light guide sections (first light guide sections 13A and 13C and second light guide sections 13B and 13D) in the circumferential direction. The first light guides 13A and 13C and the second light guides 13B and 13D are alternately provided in the circumferential direction. Further, each of the first light guide portions 13A and 13C and the second light guide portions 13B and 13D is a translucent plate-like member, and has one end in the radial direction (the end on the side close to the central axis L). ) Is provided with a light incident portion 131 that takes in the detection light L2 emitted from the light source 12 for detection.

  Here, each of the first light guides 13A and 13C and the second light guides 13B and 13D includes a light incident part 131 on the side opposite to the side where the detection target space 10R is located. Further, in this embodiment, the auxiliary light guide unit 133 is disposed in a state where the detection target space 10R is set, and the detection light source 12 is fixed to the end of the auxiliary light guide unit 133. It is arranged in the state.

  Therefore, in this embodiment, as shown in FIG. 7A, the light source rotating body 13 rotates around the central axis L, and the first light guide portion 13A arrives at a position overlapping the detection target space 10R. During one period, the auxiliary light guide part 133 and the light incident part 131 of the first light guide part 13 </ b> A face each other, and the detection light L <b> 2 emitted from the detection light source 12 passes through the auxiliary light guide part 133 to the first guide. Incident on the light portion 13A. Therefore, since the detection light L2a is emitted from the first light guide portion 13A to the detection target space 10R, the detection target space 10R has an intensity from the one end portion in the radial direction toward the other end portion in the radial direction. A first light intensity distribution L2Xa that monotonously increases linearly is formed. The same applies to the first period when the first light guide portion 13C arrives at a position overlapping the detection target space 10R.

  Further, as shown in FIG. 7B, during the second period in which the light source rotating body 13 rotates around the central axis L and the second light guide unit 13B arrives at a position overlapping the detection target space 10R, The light guide part 133 and the light incident part 131 of the second light guide part 13B face each other, and the detection light L2 emitted from the light source for detection 12 enters the second light guide part 13B via the auxiliary light guide part 133. To do. Accordingly, since the detection light L2b is emitted from the second light guide portion 13B to the detection target space 10R, the detection target space 10R has an intensity from one radial end to the other radial end. A second light intensity distribution L2Xb that monotonously decreases linearly is formed. The same applies to the second period when the second light guide unit 13D arrives at a position overlapping the detection target space 10R.

  Even in the optical position detection apparatus 10 configured as described above, the position of the target object Ob can be detected by using the light reception result of the photodetector 30 as in the first embodiment. The first light guides 13A and 13C have a function of emitting light whose intensity increases monotonously from one end to the other end, and the second light guides 13B and 13D are the first light guides. Contrary to the portions 13A and 13C, it has a function of emitting light whose intensity decreases monotonously from one end to the other end. Accordingly, the first light guide parts 13A and 13C and the second light guide parts 13B and 13D only have to have a single emission characteristic, so that the intensity appropriately monotonously changes in the method using the light guide plate. The same effects as those of the first embodiment can be obtained, such as being able to form a distribution.

  Further, in this embodiment, since the detection light source 12 is arranged in a fixed state, there is an effect that power supply to the detection light source 12 is easy.

  In addition, in this embodiment, since the auxiliary light guide unit 133 is used, the layout of each component is easy, such as the detection light source 12 need not be arranged near the central axis L.

[Embodiment 3 / Distribution by auxiliary light guide unit]
FIGS. 8A and 8B are explanatory views schematically showing a main part of the optical position detection device 10 according to the third embodiment of the present invention. FIGS. 8A and 8B show the rotation for the light source in the first period. It is explanatory drawing which shows the angular position of the body 13, and explanatory drawing which shows the angular position of the rotary body 13 for light sources in a 2nd period. Since the basic configuration of this embodiment is the same as that of Embodiment 1, common portions are denoted by the same reference numerals and description thereof is omitted.

  As shown in FIG. 8, the optical position detection device 10 of the present embodiment also includes the detection light source 12 that emits the detection light L2 and the detection light L2 emitted from the detection light source 12 as in the first embodiment. Light for detecting a part of the detection light L3 reflected by the target object Ob in the emission side space (detection target space 10R) of the detection light L2 from the light source rotation body 13 The light source rotator 13 is rotatable about the axis L0.

  Also in the present embodiment, as in the first embodiment, the light source rotating body 13 includes a plurality of light guide sections (first light guide sections 13A and 13C and second light guide sections 13B and 13D) in the circumferential direction. The first light guides 13A and 13C and the second light guides 13B and 13D are alternately provided in the circumferential direction. Further, each of the first light guide portions 13A and 13C and the second light guide portions 13B and 13D is a translucent plate-like member, and has one end in the radial direction (the end on the side close to the central axis L). ) Is provided with a light incident portion 131 that takes in the detection light L2 emitted from the light source 12 for detection.

  In this embodiment, each of the first light guides 13A and 13C and the second light guides 13B and 13D includes a light incident part 131 on the side opposite to the side where the detection target space 10R is located. Further, in this embodiment, the auxiliary light guide 134 is arranged in a fixed state on the central axis L of the light source rotating body 13, and the detection light source 12 is fixed to the end of the auxiliary light guide 134. Is arranged in. The photodetector 30 and the reference light source 12R are arranged in a state of being fixed in the concave portion of the auxiliary light guide unit 134.

  Here, the auxiliary light guide part 134 distributes the detection light L2 emitted from the light source 12 for detection and guides it to the light incident parts 131 of the first light guide parts 13A and 13C and the second light guide parts 13B and 13D. . For this reason, the detection light L2 is always emitted from any of the first light guides 13A and 13C and the second light guides 13B and 13D. However, the detection light L2 is emitted to the detection target space 10R only from the light guide unit that has arrived at the position overlapping the detection target space 10R among the first light guide units 13A and 13C and the second light guide units 13B and 13D. The detection light L2 emitted from the light guide is blocked by a light shielding member or the like and is not emitted to the detection target space 10R.

  In the optical position detection device 10 configured as described above, as illustrated in FIG. 8A, the light source rotator 13 rotates around the central axis L, and the first light guide 13A enters the detection target space 10R. Since the detection light L2a is emitted from the first light guide portion 13A to the detection target space 10R during the first period that has arrived at the overlapping position, the detection target space 10R has a radial direction from one end portion in the radial direction to the other radial direction. A first light intensity distribution L2Xa is formed in which the intensity increases linearly and monotonously toward the side end. The same applies to the first period when the first light guide portion 13C arrives at a position overlapping the detection target space 10R.

  Further, as shown in FIG. 8B, during the second period in which the light source rotator 13 rotates around the central axis L and the second light guide 13B arrives at a position overlapping the detection target space 10R, 2 Since the detection light L2b is emitted from the light guide 13B to the detection target space 10R, the intensity linearly increases from the one end in the radial direction to the other end in the radial direction in the detection target space 10R. A second light intensity distribution L2Xb that monotonously decreases is formed. The same applies to the second period when the second light guide unit 13D arrives at a position overlapping the detection target space 10R.

  Even in the optical position detection apparatus 10 configured as described above, the position of the target object Ob can be detected by using the light reception result of the photodetector 30 as in the first embodiment. The first light guides 13A and 13C have a function of emitting light whose intensity increases monotonously from one end to the other end, and the second light guides 13B and 13D are the first light guides. Contrary to the portions 13A and 13C, it has a function of emitting light whose intensity decreases monotonously from one end to the other end. Accordingly, the first light guide parts 13A and 13C and the second light guide parts 13B and 13D only have to have a single emission characteristic, so that the intensity appropriately monotonously changes in the method using the light guide plate. The same effects as those of the first embodiment can be obtained, such as being able to form a distribution.

  In this embodiment, the auxiliary light guide 134 and the detection light source 12 are fixed. However, the auxiliary light guide 134 and the detection light source 12 rotate integrally with the light source rotator 13. May be.

[Embodiment 4]
FIG. 9 is an explanatory diagram showing a main part of the optical position detection device 10 according to the fourth embodiment of the present invention. Since the basic configuration of this embodiment is the same as that of Embodiment 1, common portions are denoted by the same reference numerals and description thereof is omitted.

  In the first to third embodiments, the light guides (first light guides 13A and 13C and second light guides 13B and 13D) have a plate shape extending linearly, but are shown in FIG. Thus, the shape which the light guide part (1st light guide part 13A, 13C and 2nd light guide part 13B, 13D) protrudes in circular arc shape toward the detection object area | region may be sufficient. According to this configuration, it is possible to detect in which angle direction the target object Ob is located from the light guides (the first light guides 13A and 13C and the second light guides 13B and 13D).

[Other embodiments]
In the above embodiment, the light source rotating body 13 is provided with the two first light guide portions 13A and 13C and the two second light guide portions 13B and 13D. However, the first light guide portion and the second light guide portion are provided. One part may be provided one by one.

  In the above embodiment, only a part in the rotation direction of the light source rotator 13 is used as the detection target space 10R. However, a plurality of locations in the rotation direction of the light source rotator 13 may be used as the detection target space 10R. . A plurality of detection target spaces 10R formed in the rotation direction of the light source rotator 13 may be a continuous detection target space 10R.

  In the above embodiment, the two first light guide portions 13A and 13C and the two second light guide portions 13B and 13D both form a light intensity distribution whose intensity varies in the radial direction. 13A and the second light guide part 13B form a light intensity distribution whose intensity changes in the radial direction, and the first light guide part 13C and the second light guide part 13D both have a light intensity distribution whose intensity changes in the circumferential direction. May be formed. According to such a configuration, the two first light guide portions 13A and 13C and the two second light guide portions 13B and 13D both form a light intensity distribution whose intensity varies in the radial direction. 13A and the second light guide part 13B form a light intensity distribution whose intensity changes in the radial direction, and the first light guide part 13C and the second light guide part 13D both have a light intensity distribution whose intensity changes in the circumferential direction. May be formed. According to such a configuration, the radial position and the circumferential position of the target object Ob can be detected.

[Configuration example of equipment with position detection function]
With reference to FIG. 10 and FIG. 11, the display apparatus with a position detection function provided with the optical position detection apparatus 10 to which the present invention is applied will be described.

(Specific example 1 of the device 1 with a position detection function)
FIG. 10 is an explanatory view of a screen device with a position detection function (apparatus with a position detection function) to which the present invention is applied, and FIGS. It is explanatory drawing which shows a mode typically, and explanatory drawing which shows typically a mode seen from the horizontal direction. In the screen device with a position detection function of the present embodiment, the configuration of the optical position detection device 10 is the same as the configuration described with reference to FIGS. Omitted.

  The screen device 8 with position detection function (device 1 with position detection function) shown in FIGS. 10A and 10B is from an image projection apparatus 250 (image generation apparatus) called a liquid crystal projector or a digital micromirror device. A screen 80 (viewing surface constituent member 40) on which an image is projected and the optical position detection device 10 described with reference to FIGS. 1 to 9 are provided. The image display light Pi is enlarged and projected from the projection lens system 210 provided in the unit 241 toward the screen device 8. Therefore, in the screen device 8 with a position detection function, the viewing surface 41 on which information is visually recognized is configured by the screen surface 8a on which an image is projected on the screen 80 (viewing surface constituent member).

  In the screen device 8 with a position detection function, the optical position detection device 10 is provided on the back surface 8b side of the screen 80, for example. Therefore, the optical position detection device 10 emits the detection light L2 to the detection target space 10R set on the screen surface 8a side from the side opposite to the screen surface 8a in the screen 80. In addition, the light receiving unit provided in the optical position detection device 10 detects the detection light L <b> 3 that is reflected by the target object Ob and transmitted through the screen 80. Accordingly, the screen 80 having a light-transmitting property with respect to the detection light L2 is used. More specifically, the screen 80 is composed of a fabric having a white paint applied to the screen surface 8a side or a white screen made of an embossed white vinyl material, and is transparent to the detection light L2 made of infrared light. As the screen 80 having light properties, a silver screen having a high silver color in order to increase the reflectance of light, and the fabric surface constituting the screen surface 8a side is subjected to resin processing to increase the reflectance of light. A pearl screen, a bead screen in which fine glass powder is applied on the screen surface 8a side to increase the reflectance of light, can be used. In such a case, the screen 80 can detect the detection light L2 made of infrared light. And has translucency. The screen 80 may be provided with a black light-shielding layer on the back surface 8b for the purpose of improving the quality of the displayed image. In such a case, the light-shielding layer has a light-transmitting portion made of a hole. A plurality of are formed.

  In the screen device 8 with a position detection function configured as described above, the detection target space 10R is a rectangular region when viewed from the normal direction with respect to the screen device 8, and an image is projected by the image projection device 250 in the screen device 8 with a position detection function. Overlaps the projected area (image display area 20R). For this reason, in the screen device 8 with a position detection function of the present embodiment, for example, if the target object Ob such as a fingertip is brought close to a part of the image projected on the screen 80, the position of the target object Ob is switched. It can be used as input information such as instructions.

  In the present embodiment, the screen device for a projection display device on which an image is projected from the image projection device 250 has been described as the screen device 8 with a position detection function. However, the optical position detection device 10 is applied to a screen for an electronic blackboard. May be provided to constitute a screen device with a position detection function for an electronic blackboard.

(Specific example 2 of the device 1 with a position detection function)
FIG. 11 is an explanatory diagram of a projection display device with a position detection function (apparatus with a position detection function) to which the present invention is applied. FIGS. 11A and 11B show a projection display device with a position detection function. It is explanatory drawing which shows a mode seen from diagonally upward, and explanatory drawing which shows a mode seen from the horizontal direction typically. In the projection display device with a position detection function of this embodiment, the configuration of the optical position detection device 10 is the same as the configuration described with reference to FIGS. Description is omitted.

  11A and 11B, a projection display device 200 with a position detection function (device 1 with a position detection function) is an image projection device 250 (image generation device) called a liquid crystal projector or a digital micromirror device. ) And the optical position detection device 10 described with reference to FIGS. 1 to 9. The image projection device 250 enlarges and projects the image display light Pi from the projection lens system 210 provided on the front surface portion 241 of the housing 240 toward the screen 80. In the projection display device 200 with a position detection function, the screen surface 8a on which an image is projected on the screen 80 constitutes a viewing surface 41 on which information is visually recognized.

  In the projection display device 200 with a position detection function, the optical position detection device 10 is mounted on the image projection device 250 arranged on the screen surface 8a (viewing surface 41) side of the screen 80. For this reason, the optical position detection device 10 emits the detection light L2 from the image projection device 250 along the viewing surface 41 of the screen 80 (viewing surface constituent member 40). Further, the optical position detection device 10 detects the detection light L <b> 3 reflected by the target object Ob in the image projection device 250.

  In the projection display device 200 with the position detection function configured as described above, the detection target space 10 </ b> R is a rectangular region when viewed from the normal direction with respect to the screen 80, and an image is projected on the screen 80 by the image projection device 250. It overlaps with the area (image display area 20R). For this reason, in the projection display device 200 with a position detection function of the present embodiment, for example, if the target object Ob such as a fingertip is brought close to a part of the image projected on the screen 80, the position of the target object Ob is imaged. It can be used as input information such as a switching instruction.

1 ··· Equipment with position detection function, 10 · · Optical position detection device, 10R · · Detection target space (detection light emission side space), 12 · · Light source for detection, 12A, 12C · · · Light source for first detection , 12B, 12D, second light source for detection, 12R, light source for reference, 13, rotating body for light source, 13A, 13C, first light guide unit, 13B, 13D, second light guide unit, 30 ..Photodetector, 56 ..Position detector, 130 ..Light emitting part, 131 ..Light incident part, 133, 133 A to 133 D, 134 ..Auxiliary light guide part

Claims (10)

An optical position detection device for optically detecting the position of a target object,
A light source for detection that emits detection light;
A first light guide part that takes in the detection light emitted from the light source for detection into the light incident part and emits the light as a light whose intensity monotonously increases from one side end part to the other side end part of the light emission part; And a second light guide part that takes in the detection light emitted from the light source for detection inside the light incident part and emits the light as a light whose intensity decreases monotonously from one side end part to the other side end part of the light emission part A rotating body for a light source that rotates at different angular positions,
A photodetector that receives the detection light reflected by a target object located in a space on the emission side of the detection light from the rotating body for the light source;
A position detection unit that detects the position of the target object based on a light reception result of the photodetector;
An optical position detection device characterized by comprising: The detection light source is provided as a first detection light source and a second detection light source that rotate integrally with the light source rotator,
The first light source for detection emits the detection light toward a light incident part of the first light guide part,
The optical position detection device according to claim 1, wherein the second light source for detection emits the detection light toward a light incident portion of the second light guide portion. The detection light emitted from the first light source for detection is directly incident on the light incident part of the first light guide part,
The optical position detection device according to claim 2, wherein the detection light emitted from the second light source for detection is directly incident on a light incident portion of the second light guide portion.   A first auxiliary light guide that guides the detection light emitted from the first light source for detection to a light incident portion of the first light guide; and the detection light emitted from the second light source for detection. The optical position detection device according to claim 2, further comprising: a second auxiliary light guide unit that guides to a light incident unit of the two light guide units. The detection light source is fixed;
The light emitted from the light source for detection is incident on the light incident portion of the first light guide portion and the light incident portion of the second light guide portion by the rotation of the light source rotating body. The optical position detection device according to claim 1, wherein the optical position detection device is switched to a second state.   The detection light emitted from the detection light source is directly incident on the light incident portion of the first light guide portion in the first state, and is incident on the light incident portion of the second light guide portion in the second state. The optical position detection device according to claim 5, wherein the optical position detection device is directly incident.   The detection light emitted from the light source for detection is guided to the light incident portion of the first light guide in the first state, and is guided to the light incident portion of the second light guide in the second state. The optical position detection device according to claim 5, further comprising a light guide unit.   An auxiliary light guide unit is provided that distributes the detection light emitted from the light source for detection and guides the detection light to the light incident unit of the first light guide unit and the light incident unit of the second light guide unit. The optical position detection device according to claim 1. A reference light source for making reference light incident on the photodetector without going through the exit-side space;
The position detection unit detects the position of the target object based on a result of driving the detection light source and the reference light source so that the received light intensities of the photodetectors are equal. The optical position detection device according to any one of 1 to 7.   A device with a position detection function, comprising the optical position detection device according to any one of claims 1 to 9.

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