KR19990088087A - Coordinate input device - Google Patents

Abstract

The present invention aims to provide a coordinate input device which realizes high stability and reliability, high detection speed and detection accuracy, which are difficult in the prior art, and whose structure is simple and inexpensive, and emits light by incidence of light. And a light source unit including condensing optical means, light emitting means, and power supply means for injecting spot light onto the surface of the flat plate member, and a plurality of plates disposed on the side surface of the flat plate member. And a detection circuit section for receiving an output signal of the light receiver and outputting a signal related to the position coordinates of the spot light in the flat plate member, the peripheral portion of the flat plate member corresponding to each of the plurality of light receivers. A plurality of concave surfaces provided on side surfaces of the flat plate member It includes a light absorbing member.

Description

Coordinate Input Device {COORDINATE INPUT DEVICE}

The present invention relates to a coordinate input device that detects the position coordinates of a point instructed on a plane and transmits the detected position coordinates to various information apparatuses as pointing information. In particular, the present invention has occurred when a light beam is projected onto a plane of a transparent flat plate. The present invention relates to a coordinate input device using an optical method for detecting coordinates from the amount of attenuation of propagated light inside the flat plate.

With the development of information equipment, a method of performing the operation of the device by instructing the screen of the display device has become widespread. At the same time, the importance of a coordinate input device called a pointing device for indicating a point on the screen and transmitting the position coordinate information increases, and various methods have been proposed so far. Mouse is best known as a representative product type. In recent years, joysticks are widely used for games.

The current mouse environment as the first prior art is apparent from the description described on pages 75 to 79 of the November 1997 issue of Electronics magazine, which is incorporated by reference. Most of the mouse is a so-called ball mouse that uses the rotation of the internal ball to operate the rotary encoder. As described on page 77 of the above reference, the ball mouse has a problem in that it is difficult to rotate and transmit due to the adhesion of dust, which causes the detection of positional coordinates to be poor, and thus requires regular cleaning. In addition, it is difficult to increase the detection accuracy of the position coordinate because of slippage in the rotation transmission system.

As an apparatus for realizing high detection accuracy, there is an optical mouse that reads the orthogonal stripe pattern printed on the mouse pad with the light receiving element. However, as described on page 78 of the above reference, the apparatus is suitable for the orthogonal stripe pattern. It is not easy to design and adjust the device to read in contrast, and it is easy to be influenced by the dirt on the surface of the mouse pad, and there is a limit to reducing the line width of the stripe pattern and the size of the light receiving window of the light receiving element, so that the resolution can be increased. There is no such problem.

The joystick widely used as the second prior art has a mainstream method in which rotations in arbitrary directions between operations are decomposed into rotations in two directions on a plane, and each rotation angle is read by a rotary encoder. As an example, FIG. 1 of Japanese Patent Laid-Open No. 9-134646 shows a schematic exploded perspective view of a joystick device. In this figure, the spherical part (Elevation 463) provided integrally with the operation member (Elevation 460) is inserted into the through hole (Elevation 492A), and this part is called the point of tilting operation. The flange (operation 462) of the operation member and the flange and the bulbous portion are respectively provided in the first interlocking member (operation 420), and the groove (operation 421A) and the second interlocking member (operation 430) are provided. It is inserted into the provided groove part (Figure 431a), and the tilting motion of the operation member is decomposed into a rotational motion orthogonal to each of the two interlocking members. The two disassembled rotational movements are transmitted to two rotary encoders each consisting of first and second discs (e.g., 440 and 450) and first and second sensors (e.g., 470 and 480), respectively. Coordinate information corresponding to a state can be obtained.

As shown in the above second prior art, the joystick device disassembles the tilting motion of the operating member into two rotating elements through the mechanical element. For this reason, a structure becomes complicated, price reduction is difficult, it is impossible to raise coordinate detection precision, and abrasion and damage of a mechanical element generate | occur | produce, and there exists a problem of deteriorating long-term reliability. In addition, since a rotary encoder handles a digitalized signal, it is generally difficult to obtain a high resolution at a low rotational speed and to increase the resolution of coordinate detection.

In the third prior art, a joystick which reduces mechanical elements and increases resolution by analog signal detection is shown in FIG. 2 of Japanese Patent Laid-Open No. 61-27605. According to FIG. 2, the lever (Fig. 17) is supported in a tiltable state at a point (Fig. 20), and is connected with a spherical plate (Fig. 14) and a connecting material (Fig. 18) centered on the point. The inner and outer surfaces of the spherical plate are reflecting surfaces, the reflectance of which changes at a constant rate in a predetermined direction, and the direction of change of reflectance of the inner and outer surfaces is orthogonal to each other. A light source 10 for irradiating light and a photoelectric element for detecting the reflected light (figure 12) are fixedly disposed inside and outside the spherical plate, respectively. When the lever is tilted (tilt), the spherical plate is also integrally tilted. At this time, the two photoelectric elements can be detected as a change in the reflected light intensity to change the reflectances on the inner and outer surfaces, respectively, to obtain a coordinate signal.

In the above-mentioned third prior art, it is necessary to form the spherical shape in the spherical plate precisely, and therefore, there has been a problem that low cost is not easy. Moreover, it was very difficult to form a reflecting surface on which a reflectance changed at a constant rate on a spherical surface. Therefore, even if analog signal detection is possible in a manner, it is difficult to increase the coordinate detection accuracy practically.

In the fourth prior art, joysticks aimed at realizing a higher precision position detection are shown in FIGS. 1 and 2 of Japanese Patent Laid-Open No. 61-32131. The joystick includes a lever (figure 3) supported by a rotating material by placing a ball (figure 2) in the upper center of the casing (figure 1), and a light source (figure 5) such as an LED provided at the tip of the lever, It consists of the two-dimensional semiconductor position detector (FIG. 6) formed in the upper surface of the said casing. The two-dimensional semiconductor position detector has a structure in which a transparent conductive film, a P-type amorphous silicon layer, an I-type amorphous silicon layer, an N-type amorphous silicon layer, and a transparent conductive layer are sequentially stacked on a substrate. The two-dimensional semiconductor position detector includes x-direction electrodes (6a, 6b) and y-direction electrodes (6c, 6d), and when the light beam is incident from the light source, the amorphous silicon layer of the three-layer structure is in a conductive state. By measuring the current values flowing into the x and y direction electrodes, the coordinates of the light beam incidence position can be detected.

In the above-mentioned fourth prior art, the two-dimensional semiconductor position detector for detecting light beam incidence is constituted by a simple structure in which multilayer thin films are stacked, and the device mechanism of the operation lever is also simple, and therefore its practicality is considered to be high. However, in order to receive a light beam moving by lever operation, it is necessary to increase the area of the two-dimensional semiconductor position detector, and it is not easy to obtain a uniform detection characteristic by reducing the dispersion of the detection characteristic in this large area. Due to the above problems, in the development of the filmmaking process technology, it is indispensable to accumulate a lot of know-how, and furthermore, it should be a technology development aimed at low cost, and furthermore, since investment in facilities for development and production is large, anyone can easily start. Obviously, it's not something that can be done.

A joystick which can be easily configured by anyone using a commercially available CCD (Charge Coupled Device) image sensor is shown in FIG. 1 of Japanese Patent Laid-Open No. 61-276014. According to Fig. 1 of the above reference, the joystick main body portion (Fig. 10) of the dark box structure is provided with a lever (Fig. 11), a lens (Fig. 13), and a two-dimensional CCD sensor (Fig. 14). 12 is installed to move in conjunction with the movement of the lever. Light from the light source is collected by the lens and irradiated as a light spot on the two-dimensional CCD sensor. In response to the movement of the lever, the light spot moves on the two-dimensional CCD sensor. The two-dimensional CCD sensor is scanned in the X and Y directions by a control signal, and outputs X and Y coordinate signals indicating the position of the light spot by detecting the level of the resulting voltage signal.

As a problem of the fifth prior art, when the tilting angle of the lever is increased, the distance between the light source and the two-dimensional CCD sensor surface is increased, and the light condensing position of the light is shifted by the fixed lens. The light spot on the surface becomes wider. Also, the area of the two-dimensional CCD sensor is generally not large. In the above prior art with the two problems as described above, the tilt angle of the lever is limited to a small range, so that it is difficult to use it incompatible with the operation sensitivity of the human hand, thereby increasing the accuracy of the control. it's difficult.

Another problem with the fifth prior art is that the position coordinates of the light spots cannot be output unless the two-dimensional CCD sensor is scanned by completing the X and Y directions. Normally, the scan in both X and Y directions is performed at a rate of 60 times per second, which means that the coordinate detection speed of the light pen cannot be more than 60 points per second. That is, when the light pen is moved quickly, there is a problem that only the intermittent coordinate position can be detected.

In the sixth prior art, in Fig. 1 of Japanese Patent Application Laid-Open No. 58-10275, since the configuration is simple and transparent, a graphic input device which can be used in various display devices is displayed. According to FIG. 1 of the reference, the graphic input device includes a phosphor that absorbs light and emits fluorescence, and has a structure in which upper and lower surfaces of the phosphor are coated with a low refractive index layer (FIG. 1). ), The light intensity incident to light from the light pen (Elevation 2) which enters light having a wavelength corresponding to the absorption wavelength of the flat plate (input plate), and propagates the light intensity propagated around the flat plate (input plate). 3a, 3b, 3c, and 3d), and outputs the position coordinates of the light pen from the output electrical signal.

As a problem with the graphic input device according to the sixth prior art, when using this indoor, external light from a ceiling lamp is input to the flat plate (input plate), and the phosphor contained in the flat plate (input plate) This is to excite and emit light. Since light is almost uniformly emitted within the flat panel (input panel) and light propagates around the flat panel (input panel), the light is propagated around the flat panel (input panel). The light gathered becomes stronger. As a result, in the circumference | surroundings of the said flat plate (input board), the light from the said light pen is buried in the light by the said external light, and it becomes difficult to output the position coordinate of the said light pen.

As another problem of the graphic input device according to the sixth prior art, the light propagating to the light receiving element is propagated directly from the light incident part from the light pen, but is also reflected around the flat plate (input plate). It includes the light that has been made. As a result, it is difficult for the light pen to output precise coordinate positions.

In the seventh prior art, Japanese Patent Application Laid-Open No. 4-127313 discloses a light reflected by a light emitting pen that incorporates a light emitting element on an input panel provided with an XY matrix optical waveguide including a fluorescent material. Disclosed is an optical coordinate input device which detects a position coordinate in which light excited and propagated as it propagates in an optical waveguide as it is, is received by a light receiving element located at a light emitting end, and the light is reflected by a light emitting light pen.

In the seventh prior art, the input panel having the X-Y matrix structure by the optical waveguide requires precise processing technology and is very expensive at present. Moreover, the light receiving element string which has a light receiving element corresponding to each one of an optical waveguide must be comprised, it is not easy to have uniform element characteristic, and it has a problem that it is difficult to reduce the cost of a light receiving element string. Furthermore, since there is a need for a precision assembly technique for realizing precise positioning between individual optical waveguides and light receiving elements, there is a problem in mass productivity and a high price of equipment.

In the eighth prior art, Japanese Patent Application Laid-Open No. 61-125640 discloses a slit provided on a flat plate made of a material that does not transmit light exposed to two adjacent corner portions on a display screen, and light other than visible light. An input device comprising a light pen which emits light to a light pen and a light receiving sensor group arranged on an arc centered on the slit so as to receive light transmitted through each slit from the light emitted by the light pen.

In the eighth prior art, a plurality of light receiving sensors are required to form a light receiving sensor group, and due to problems such as the need to arrange these light receiving sensors precisely on an arc, the size and fineness of the light receiving sensor There is a difficult problem such as precision assembly for arranging a light receiving sensor on a lake.

In another prior art relating to other optical input devices, a pointing device using a light pen having drive power frequency selection means is disclosed in Japanese Patent Laid-Open No. 61-282912. Moreover, the light spot position detection apparatus which remove | eliminates the influence of external light by performing light emission of light pens interchangeably is disclosed by Unexamined-Japanese-Patent No. 63-155320.

As described in each of the prior arts above, in each of the prior arts, a coordinate input device is known which realizes high stability and reliability, high detection speed and detection precision, and satisfies all conditions of simple structure and low price. not.

More specifically, the ball mouse, which is widely used at present, uses a frictional transmission system, so that the detection accuracy of the position coordinate is low, and if the rotating part is not cleaned regularly, the position mouse causes a poor detection of the position coordinate. there is a problem.

Since the optical mouse requires high sensitivity of the detection unit, it is difficult to design and adjust the device, and also has a problem of low stability and reliability because it is affected by the dirt on the surface of the mouse pad. Moreover, there is a problem that it is difficult to increase the resolution of coordinate detection.

Rotary encoder-type joysticks, which are widely used among various other joysticks, use a large number of mechanical elements, and thus have a problem of complicated structure, low cost, high detection precision, and high reliability. Moreover, it is also difficult to increase the resolution of coordinate detection.

An optical joystick that uses spherical concave and convex shapes as reflecting surfaces whose reflectance changes at a constant rate in a constant direction has a problem that it is difficult to increase the accuracy of forming the reflecting surface and cannot increase the detection accuracy.

As a problem of an optical joystick using a two-dimensional semiconductor position detector formed by stacking three types of semiconductor thin films between upper and lower transparent conductive films, the two-dimensional semiconductor position detector is not yet commercially available, and it requires a huge investment and time to develop it. there is a problem.

Optical joysticks using a commercially available two-dimensional CCD sensor are difficult to use because the tilt angle of the operating lever is limited to a small range and do not match with the human sense of operation, and it is difficult to increase the control accuracy. In addition, there is a problem that the coordinate detection speed cannot be high due to the limitation by the scan speeds in both X and Y directions.

In the figure input device which inputs light with a light pen to a flat plate (input plate) containing phosphors, and detects the light intensity by using a light receiving element arranged around the electric flat plate (input plate), and outputs coordinate signals. Due to the influence of external light caused by this, there is a problem that detection of the position coordinate of the light pen is difficult. In addition, there is a problem that the light pen is difficult to detect the precise coordinate position due to the influence of the reflected light on the periphery of the flat plate (input plate).

[0003] An optical coordinate input device comprising an input panel with an X-Y matrix optical waveguide has a problem in that uniformity and low cost of the light receiving element string, low cost of the input panel, mass production of the device, or low cost of the device are all difficult.

An input device for obtaining coordinate positions from angles of light passing through slits exposed to two adjacent corner portions presents technical and economical problems for precisely arranging a plurality of sensors on an arc.

SUMMARY OF THE INVENTION An object of the present invention is to provide a coordinate input device having high practicality by solving the problems of the above-described prior arts.

1A and 1B are side and plan views, respectively, schematically showing a coordinate input device according to a first embodiment of the present invention;

2 is a block diagram schematically showing the shape of the light source means as one embodiment of the frequency selection means;

3 is a block diagram schematically illustrating an embodiment of a detection circuit unit.

4 is a schematic view for explaining the principle of light propagation inside the plate member.

5 is a schematic view for explaining the principle of detection of a specific position coordinate.

6 is a circuit diagram schematically showing an embodiment of the coordinate position calculation circuit.

7 is a sectional view schematically showing a coordinate input device according to a second embodiment of the present invention.

8 is a cross-sectional view schematically showing a coordinate input device according to a third embodiment of the present invention.

<Description of the code | symbol about the main code of the drawing>

101: fluorescent dye 102: plate member

105: light source unit 106: light emitting means

107: power supply means 108: condensing optical means

109: frequency selection means 110: drive circuit means

111: detection circuit section 112: oscillation circuit means

115: filter circuit means 116: signal processing means

120: coordinate position calculation circuit 122: addition circuit

123: optical path 124: light injection direction

125: boundary angle 126: radio wave light

130: manual operation 131: spherical iron surface

132: support plate 133: through hole

136: tube 138: surface protective layer

139: mouse 140: right angle prism

The coordinate input device of the present invention comprises a flat plate member which emits light upon incidence of light and generates internal propagation light by the light emission, and a condensing optical means, a light emitting means, and a power source means for injecting spot light onto the surface of the flat plate member. A light source unit including a light source unit, a plurality of light receivers arranged on the side surface of the flat plate member, and a detection circuit unit which receives an output signal of the light receiver and outputs a signal related to the position coordinate of the spot light in the flat plate member And a plurality of concave surfaces provided on side surfaces of the flat plate member corresponding to each of the plurality of light receivers.

According to another aspect of the present invention, there is provided a coordinate input device comprising: a flat plate member which emits light upon incidence of light and generates internal propagation light by the light emission; and a condensing optical means for injecting spot light onto the surface of the flat plate member; A light source unit having light emitting means and power supply means, a plurality of light receivers arranged on the side surface of the flat plate member, and a signal related to the position coordinates of the spot light in the flat plate member in response to an output signal of the light receiver; It is configured as a detection circuit for outputting, characterized in that it has a light absorbing member arranged in close contact with the side except for the portion where the concave surface is formed around the plate member.

Further, a coordinate input device according to another aspect of the present invention is a flat plate member that emits light upon incidence of light and generates internally propagated light by light emission, and condenses spot light on the surface of the flat plate member. A light source unit including an optical means, a light emitting means, and a power supply means, a plurality of light receivers disposed on side surfaces of the flat plate member, and a position coordinate of the spot light in the flat plate member in response to an output signal of the light receiver; A detection circuit section for outputting a related signal, comprising: a plurality of concave surfaces provided on side surfaces of the flat plate member corresponding to each of the plurality of light receivers, and a side surface of which the concave surface around the flat plate member is formed. It characterized in that it has a light absorbing member arranged in close contact with the.

In the coordinate input device provided with each of the above features, the concave surface may have a cylindrical surface or a spherical surface shape.

The light absorbing member may include an optical member having a refractive index equal to or greater than that of the flat plate member, and a light absorbing medium included in the optical member.

In any of the above cases, the light source portion can be arbitrarily moved.

In addition, the light source portion is provided inside a manual operation consisting of a rotating material around a fixed point on a vertical line extending upward through a substantial center of the surface of the flat plate member, wherein the flat plate member is external light at the same time as the manual operation. The manual operation section may be arranged such that the spot light is formed on a straight line having the same inclination angle as that of the manual operation section through the fixing point.

In addition, a transparent protective layer having a refractive index smaller than that of the flat plate member is laminated on the surface of the flat plate member, and the light source unit is provided inside the mouse for manually moving the transparent protective layer on the surface of the flat plate member. It is also preferable that the light is emitted from the bottom of the mouse, so that the spot light is incident on the surface of the flat plate member.

In the coordinate input device according to the present invention configured as described above, a light receiver is disposed at a portion where a concave surface around a flat plate member containing a fluorescent dye is formed. Of the light reaching the concave surface, only the light directed to each light receiver is navigated toward each light receiver, and other light is refracted toward the direction other than the light receivers when it is deviated from the concave surface to the outside. As a result, only the light component that should originally receive light is received, so that the detection accuracy can be increased.

In addition, by arranging the light absorbing member on the side except for the portion where the concave surface is formed around the flat plate member, the light propagating inside the flat plate member is prevented from being absorbed and reflected by the side surface. As a result, the light generated by the light emission of the fluorescent dye in the spot light incident part is detected only by the straight component to the light receiver, so that the position coordinate of the spot light incident part can be detected with higher accuracy.

In addition, the light absorbing member is composed of an optical member including a light absorbing medium, the refractive index of the optical member is equal to or larger than that of the transparent flat member, the light propagating inside the transparent flat member is the side The light penetrates and enters the optical member to be absorbed by the light absorbing medium included in the optical member.

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

First embodiment

1A and 1B are side and plan views, respectively, schematically showing a coordinate input device according to a first embodiment of the present invention.

As schematically shown in FIGS. 1A and 1B, the four corners 100a, 100b, 100c, and 100d of the flat plate member 102 formed with the fluorescent dye 101 uniformly added have recesses. The light receivers 103a, 103b, 103c, and 103d are disposed toward the concave surface. The light receivers 103a, 103b, 103c, and 103d are connected to the detection circuit section 111, respectively. Thereby, only the light which propagates the inside of the flat plate member 102 and reaches the concave surfaces of the four corners 100a to 100d to the respective light receivers 103a to 103d goes toward the respective light receivers 103a to 103d. The other light is refracted toward the direction other than the light receivers 103a to 103d when it is projected outward from the concave surface. As a result, only the light component which should originally receive is received, and the detection degree becomes high.

Light absorbing members 104a, 104b, 104c, and 104d are disposed on all sides of the flat plate member 102.

The first embodiment is used in combination with the light source portion 105 which is moved by manual operation on the surface of the flat plate member 102. 1A shows the internal structure of the light source 105. As shown in FIG. 1A, the light source unit 105 forms and outputs light emitting means 106, power supply means 107 for emitting light emitting means 106, and light emitted from the light emitting means 106. Condensing optical means 108 for

The power supply means 107 includes a frequency selecting means 109 and a driving circuit means 110 connected to the frequency selecting means, and emits light at a frequency selected by the frequency selecting means 109 among a plurality of predetermined frequencies. The light emission of the means 106 is interrupted.

The frequency selecting means 109 can write and configure various well-known oscillation circuits.

For example, as shown in Fig. 2, in the case of using the oscillating circuit means 112 which can change the oscillation frequency by changing the capacitance, three different capacitors having capacitances corresponding to three predetermined oscillation frequencies are used. By 113a, 113b, 113c, the frequency can be selected at the two selection switches 114a, 114b.

It is preferable to use a light emitting diode or a laser diode as the light emitting means 106. At this time, the drive circuit means 110 is composed of a circuit for supplying the light emitting means 106 with a pulse current intermittent at the frequency selected by the frequency selecting means 109.

3 shows an example of the detection circuit section 111. As shown in FIG. 3, the detection circuit section 111 includes a filter circuit section 115, a signal processing circuit section 116, and an addition circuit section 122. The filter circuit means 115 is composed of band pass filter circuits 117a, 117b, 117c, 117d, 118 and 119, and the signal processing circuit means 116 comprises a coordinate position calculation circuit 116, a select processing circuit 121a, 121b), and the addition circuit section 122 adds the outputs from the respective light receivers 103a to 103d.

The detection signal in the light receivers 103a, 103b, 103c, and 103d is an AC signal having a predetermined frequency. In the above embodiment, this predetermined frequency is described as three types represented by f ₁ , f ₂ and f ₃ . The band pass filter circuits 117a to 117d constituting the filter circuit means 115 are provided for the frequency f ₁ , and each of the band pass filter circuits 118 and 119 is for the frequencies f ₂ and f ₃ , respectively. I am preparing. When the signals detected by the respective receivers 103a to 103d are inputted, they are outputted through a band pass filter circuit for any one of three frequencies.

In the first embodiment, the signal having the frequency f ₁ is input to the coordinate position calculating circuit 120 of the signal processing circuit means 116, whereby the position coordinate signals V (x) and V (y) are The output signals having frequencies f ₂ and f ₃ are input to the select processing circuits 121a and 121b of the signal processing circuit means 116, respectively, resulting in two select signals V _s1 and V _s2 . Is output. In order to output the select signal, any one of the detection signals may be written from one receiver, but in the above embodiment, the detection signals from all the receivers are added to the addition circuit section 122 to add up to stabilize the operation. have. In the first embodiment, an example of outputting two select signals is shown. However, by setting only the required number of kinds of signal frequencies, it is possible to output the required number of select signals.

The operating principle of the first embodiment will be described below with reference to FIGS. 4 and 5. The spot light emitted by the light source portion 105 shown in FIG. 1 is incident therein from the surface of the flat plate member 102 as the incident light 123 shown in FIG. The fluorescent dye 101 added to the inside of the flat plate member 102 is excited and emits light when incident light is appropriate, but light is isotropically generated at this time. As shown in FIG. 4, the light emission direction 124 emitted from the inside of the flat plate member 102 is represented by an angle θ taken in a direction perpendicular to the upper and lower surfaces of the flat plate member 102. θ c,

The light emitted in the range of θc <θ <180 ° -θc is totally reflected from the upper and lower surfaces of the flat plate member 102 as the propagated light 126 indicated by the dotted line in FIG. 4 and exits the outside of the flat plate member 102. There is nothing. The propagation light 126 is slightly absorbed by the flat plate member 102 or the dispersed fluorescent dye 101 in the process of propagating the inside of the flat plate member 102, and the light intensity decreases as the propagation distance becomes longer. . In other words, the propagation distance and light intensity are inversely related. As shown in Fig. 5, the position where the fluorescent dye is excited and emitted in the flat plate member 102 having the lengths a and b, respectively, is represented by coordinates (x, y). The distances to 103a, 103b, 103c, and 103d are r ₁ , r ₂ , r ₃ , and r ₄ , respectively, and the light intensities detected by the respective receivers are denoted as I ₁ , I ₂ , I ₃ , and I ₄ , respectively. If k is proportional integer,

r ₁ = k / I ₁ ,

r ₂ = k / I ₂

r ₃ = k / I ₃

r ₄ = k / I ₄

There is a relationship. However, this relationship holds that, among the light emitted at the coordinate positions (x, y), the light propagated to all sides of the flat plate member 102 is the light absorbing members 104a, 104b, 104c, 104d shown in FIG. ) And is not reflected inside the flat plate member 102. That is, by detecting only the light propagated to the light receiver directly from the light emitting position in the flat plate member 102, the distance between the light receiver and the light emitting position can be measured accurately. In addition, there is a relationship shown as follows.

x ² + y ² = r ₁ ²

x ² + (b-y) ² = r ₂ ²

(a-x) ² + (b-y) = r ₃ ²

From these relational expressions, the position coordinates (x, y) are obtained as follows.

x = K _X (I ₃ ² -I ₂ ² ) / (I ₃ ² I ₂ ² ) + a / 2

y = K _Y (I ₂ ² -I ₁ ² ) / (I ₂ ² I ₁ ² ) + b / 2

Here, K _X and K _Y represent proportional constants. As is clear from the above relation, the position coordinate y is generally the position coordinate y as requested from one output signal of any of the two receivers (one of 103a and 103b and one of 103c and 103d) lined in the horizontal direction. Is requested from the output signals of the two receivers lined up in the longitudinal direction. First, the coordinate position calculation circuit 120 shown in FIG. 3 outputs the position coordinates (x, y) by receiving a signal from the receiver according to the above relational expression, and can be easily configured using ordinary circuit design techniques. Can be. As an example, Fig. 6 shows a circuit example constructed by using an analog multiplier and an analog operational amplifier.

The circuit shown in FIG. 6 is composed of four analog multipliers 601 ₁ to 601 ₄ and five analog operational amplifiers 602 ₁ to 602 ₅ . The light intensities I ₂ and I ₃ of the propagated light detected by the respective receivers 103b and 103c are input to each input terminal of the analog multipliers 601 ₁ and 601 ₄ , and each of these outputs is an analog multiplier 601 ₂ and an analogue. It is input to the operational amplifier 602 ₁ . The output of the analog multiplier (601 ₂₎ is input to the analog multiplier (601, _3), the output of the analog operational amplifier (602 ₁₎ is input to the analog side of the operational amplifier (602 _2). Positive side input of an analog operational amplifier (602 ₂₎ is grounded, and its output is input to the positive side of the analog multiplier at the same time, the analog operational amplifier (602 ₄₎ as soon enter the (601, _3). Between the input and output side of the analog operational amplifier (602, ₄₎ has a feedback resistor is provided for determining the amplification factor. The output of the analog operational amplifier (602 ₄₎ is the output of the analog operational amplifier (602 _4), an operational amplifier (602 ₃₎ to an output and an analog of the to generate an offset voltage a / 2 is the side of the analog operational amplifier (602 ₅₎ is input to positive side input of an analog operational amplifier (602, ₅₎ is grounded.

The output from the main portion of the circuit shown in FIG. 6 is as follows.

Analog Multiplier 601 ₁ Output = I ₂ ²

Analog Multiplier 60 ₂ Output = I ₃ ² I ₂ ²

Analog Multiplier601₃Output = I₃ ²- I₂ ²

Analog Multiplier 601 ₄ Output = I ₃ ²

Analog Operational Amplifiers 602 ₁ = I ₃ ² -I ₂ ²

ANA ₂ = (I ₃ ² -I ₂ ² ) I ₃ ² I ₂ ²

Analog Operational Amplifiers 602 ₃ = a / 2

Analog Operational Amplifiers 602 ₄ = K _X (I ₃ ² -I ₂ ² ) / I ₃ ² I ₂ ²

Analog op amp 60 ₅ = K _X (I ₃ ² -I ₂ ² ) / I ₃ ² I ₂ ² + a / 2

The input of the circuit shown in FIG. 6 is a signal from two light receivers which have passed through the filter circuit means 115 in FIG. 3, and the output is x of the position coordinates. To be able to output the y coordinate of the position by selecting a feedback resistance value of the analog operational amplifier (602 _4), a coordinate position calculation circuit 120 is configurable to the circuit shown as a second set of matching in Fig.

Glass or a plastic material can be used for the transparent member for forming the flat plate member 102. In particular, plastic optical materials such as polymethacryl, polycarbonate, and polystyrene can be suitably used because they can be formed in a low temperature range in which fluorescent dyes to be added are not decomposed. Many commercially available fluorescent dyes are known and may be used. Examples of suitable products include fluorescent dyes sold under the trade name LumogenF of BASF Japan. If this fluorescent dye is added at a rate of 0.02% with respect to the polymethicacryl resin, for example, a flat plate member suitable for the coordinate input device according to the present embodiment can be formed.

The light absorbing members 104a to 104d disposed on the side surface of the flat plate member 102 are formed by dispersing a light absorber such as carbon black on the transparent member using a transparent member similar to the flat plate member 102. Among the three kinds of plastic optical materials described above, since the polymethacryl resin has the smallest refractive index, the transparent material used for the light absorbing member when the flat member is formed of the polymethacryl resin as in the above embodiment is used. The member may use three kinds of plastic optical materials. As an example, a light absorbing member obtained by uniformly dispersing carbon black 5% in a polymethacryl resin was formed. Since this light absorption member uses the same transparent member as that of the flat plate member indicated in the embodiment, the light absorbing member can be easily adhered to the side surface of the flat plate member.

As a result of using the flat plate member and the light absorbing member shown in the first embodiment in the coordinate input device according to the present invention, the operation principle according to the present invention was confirmed, and the prior art such as stability, reliability, detection speed, detection accuracy, cost, etc. It was confirmed that this practical problem could be solved.

Second embodiment

Fig. 7 is a structural diagram showing a second embodiment of the coordinate input device according to the present invention. In the coordinate input device according to the present embodiment, the light source unit is arranged inside the manual operation period 130, and the coordinate position is designated by tilting the operation accuracy by hand operation. Since most of the components in this embodiment are the same as those in the first embodiment shown in Figs. 1A and 1B, the same reference numerals are given to those in Fig. 1, and explanations thereof are omitted.

In FIG. 7, a spherical concave surface 131 is provided at the center of rotation of the manual operation section 130, and is supported and mounted axially by being inserted into a spherical concave through hole 133 provided in the center of the support plate 132. . As a result, the manual operation section 130 can be rotated about the center 134 of the spherical convex surface 131. The center 134 is configured to be positioned on the waterline 135 passing almost the center of the flat plate member 102 that emits light upon incidence of light and propagates light therein.

The support plate 132 on which the manual operation 130 is installed is supported by the tube 136. The inside of the tube 136 is shielded from external light. For this reason, in this embodiment, it is not necessary to consider the influence by external light at all, and always stable operation is possible. Inside the manual operation 130, a light emitting means 106, a power source means 107 having a frequency selecting means 109 and a driving circuit means 110 for emitting light emitting means, and a condensing optical means 108 Is equipped. Light emitted by the light emitting means 106 and collected by the light converging optical means 108 is emitted onto a straight line 137 passing through the center 134 and is incident on the flat plate member 102 as spot light. As a result, the spot light incident position of the flat plate member 102 changes by changing the inclination of the manual operation period 130.

The coordinate detecting means and method of the spot light incident position in the second embodiment are the same as those described in the first embodiment. The basic principle is obtained by detecting the light intensities attenuated in inverse proportion to the distance by the light receivers 103a to 103d arranged in four corners of the flat plate member 120, and calculating the output signal. That is, according to the second embodiment, the rotational movement about the center 134 of the manual operation section 130 corresponds one-to-one with the coordinate of the spot light incident position of the flat plate member 102. Therefore, the coordinate input device according to the second embodiment can be used as a so-called joystick. When the second embodiment is used as a joystick, the structure is simple with almost no mechanical elements, and it is possible to lower the cost, increase the precision, high reliability, and high resolution.

Third embodiment

8 is a configuration diagram showing a third embodiment of a coordinate input device according to the present invention. In the coordinate input device according to the third embodiment, a light source unit is disposed inside a mouse of manual operation to designate a coordinate position by moving the mouse by hand operation. Since most of the components of this third embodiment are the same as those of the first embodiment shown in Fig. 1, they are denoted by the same numbers as in Fig. 1 and description is omitted.

In Fig. 8, a mouse 139 which is operated by hand operation is placed on the surface of the flat plate member 102 covered with the light-transmissive surface protective layer 138. The surface protective layer 138 is provided to prevent the surface of the flat plate member 102 from being damaged when the mouse 139 is moved. Inside the mouse 139, there is a light emitting means 106, a power source means 107 having a frequency selecting means 109 and a driving circuit means 110 for emitting the light emitting means 106, and a condensing optical means. 108 is provided, and further, a right-angle prism 140 for incidating light collected by the light-converging optical means 108 at right angles to the surface of the flat plate member 102 is arranged at the rear of the light-converging optical means 108. It is.

Light incident on the flat plate member 102 excites the fluorescent dye 101 added into the flat plate member to generate light. Light emitted from the fluorescent dye propagates inside the flat plate member and senses the light intensity at the same time as the propagation distance. The positional coordinates of incident spot light can be obtained by detecting the intensity of light propagated in all directions by the light receivers 103a to 103d arranged at four corners of the flat plate member 102. The coordinate detecting means and method of the spot light incident position are the same as those described in the first embodiment. The basic principle is that the intensity of light propagating inside the flat plate member 102 is attenuated in inverse proportion to the propagation distance, so that the output signals of the light receivers 103a to 103d arranged in the four corners are described in the above-described first embodiment. The position coordinates are obtained by arithmetic processing according to the

In order not to disturb the incidence of light from the light source portion and to not affect the propagation light inside the flat plate member, the surface protective layer 135 has good light transmittance, and the refractive index of the flat plate member 102 It is necessary to have a low relative to the refractive index. Since the light from the light source is always incident at right angles to the surface of the flat plate member 102, the incident spot light is always crushed, and precise position coordinate detection is possible.

In addition, it is important to press the noise level of the detection circuit low in order to handle the amount of signal that changes analogously, but in the third embodiment, the light source portion is covered with the mouse body, so that the incident spot light is a flat plate member ( No external light enters the vicinity of the position incident on 102, the noise level of the detection circuit can be easily pressed low, and the resolution of position coordinate detection can be increased.

Furthermore, since the analog amount is handled, the calculated position coordinate is an intermediate value calculated according to the intensity distribution of the incident spot light, so that even if the surface of the surface protection layer 135 appears to be damaged, a large detection error occurs. little. In addition, since the flat plate member corresponding to the mouse pad has a simple structure, it is easy to reduce the price.

As described above, according to the present invention, the following effects are obtained in the coordinate input device.

High detection accuracy has been realized by using a method for calculating the distance from the amount of light attenuation. Compared with the conventional apparatus using many mechanical elements, high detection accuracy and reliability are obtained, and the cost is low.

By dealing with the analog amount, high resolution and high speed detection are realized, and it is possible to be free from optical contamination and influence of the propagation direction of the propagation light, and to be stable at all times at any position, thereby enabling high accuracy detection.

By adopting a method of removing the influence of external light, it is possible to input coordinates with high precision even in a bright place. In addition, by preventing unnecessary reflection of the propagation light inside the flat plate member, it is possible to further increase the accuracy of coordinate detection.

Claims (23)

In the coordinate input device, A light source unit including a flat plate member which emits light by incidence of light and generates internal propagation light by the light emission, a condensing optical means, a light emitting means and a power source means for injecting spot light onto the surface of the flat plate member; A plurality of light receivers arranged on the side surface of the flat plate member, and a detection circuit unit which receives an output signal of the light receiver and outputs a signal relating to the position coordinates of the spot light in the flat plate member. And a plurality of concave surfaces provided on side surfaces of the flat plate member corresponding to each of the light receivers. In the coordinate input device, A light source unit including a flat plate member which emits light by incidence of light and generates internal propagation light by the light emission, a condensing optical means, a light emitting means and a power source means for injecting spot light onto the surface of the flat plate member; And a plurality of light receivers arranged on side surfaces of the flat plate member, and a detection circuit unit which receives an output signal of the light receiver and outputs a signal relating to the position coordinates of the spot light in the flat plate member. Coordinate input device characterized in that it has a light absorbing member which is arranged in close contact with the side except for the respective formed surface around the. In the coordinate input device, A flat plate member which emits light by incidence of light and generates internally propagated light by the light emission, and condensing optical means, light emitting means for injecting spot light onto the surface of the flat plate member; A light source unit including power source means, a plurality of light receivers arranged on the side surface of the flat plate member, and a signal related to the position coordinates of the spot light in the flat plate member in response to the output signal of the light receiver; A light absorbing member constructed from a detection circuit portion and arranged in close contact with a side surface of each of the plurality of light-receiving members, except for a plurality of concave surfaces provided on the side surfaces of the flat plate member and portions where the concave surface is formed around the flat plate member. Coordinate input device having a. The method of claim 1, The concave surface is a coordinate input device, characterized in that the shape attached to a cylindrical or spherical shape. The method of claim 3, The concave surface is a coordinate input device, characterized in that the shape attached to a cylindrical or spherical shape. The method of claim 1, And the light absorbing member comprises an optical member having a refractive index equal to or greater than that of the flat plate member, and a light absorbing medium included in the optical member. The method of claim 3, And the light absorbing member comprises an optical member having a refractive index equal to or greater than that of the flat plate member, and a light absorbing medium included in the optical member. The method of claim 4, wherein And the light absorbing member comprises an optical member having a refractive index equal to or greater than that of the flat plate member, and a light absorbing medium included in the optical member. The method of claim 1, And the light source unit can be arbitrarily moved. The method of claim 2, Coordinate input device, characterized in that the light source portion can be moved arbitrarily. The method of claim 3, And the light source unit can be arbitrarily moved. The method of claim 4, wherein And the light source unit can be arbitrarily moved. The method of claim 5, And the light source unit can be arbitrarily moved. The method of claim 1, The light source unit is provided inside a manual operation consisting of a rotating material centered on a fixed point on the waterline extending upward through the weak center of the surface of the flat plate member, and the flat plate member and the manual operation block external light. Disposed in the tube, wherein the manual operation section is arranged such that the spot light is formed on a straight line having the same inclination angle as the manual operation section through the fixing point. The method of claim 2, The light source unit is provided inside a manual operation consisting of a rotating material centered on a fixed point on the waterline extending upward through the weak center of the surface of the flat plate member, and the flat plate member and the manual operation block external light. Disposed in the tube, wherein the manual operation section is arranged such that the spot light is formed on a straight line having the same inclination angle as the manual operation section through the fixing point. The method of claim 3, The light source unit is provided inside a manual operation consisting of a rotating material centered on a fixed point on the waterline extending upward through the weak center of the surface of the flat plate member, and the flat plate member and the manual operation block external light. Disposed in the tube, wherein the manual operation section is arranged such that the spot light is formed on a straight line having the same inclination angle as the manual operation section through the fixing point. The method of claim 4, wherein The light source unit is provided inside a manual operation consisting of a rotating material centered on a fixed point on the waterline extending upward through the weak center of the surface of the flat plate member, and the flat plate member and the manual operation block external light. Disposed in the tube, wherein the manual operation section is arranged such that the spot light is formed on a straight line having the same inclination angle as the manual operation section through the fixing point. The method of claim 5, The light source unit is provided inside a manual operation consisting of a rotating material centered on a fixed point on the waterline extending upward through the weak center of the surface of the flat plate member, and the flat plate member and the manual operation block external light. Disposed in the tube, wherein the manual operation section is arranged such that the spot light is formed on a straight line having the same inclination angle as the manual operation section through the fixing point. The method of claim 1, A transparent protective layer having a refractive index smaller than that of the flat plate member is laminated on the surface of the flat plate member, and the light source unit is provided inside the mouse for manually moving the transparent protective layer on the surface of the flat plate member. And a light input from the bottom to arrange the spot light on the surface of the flat plate member. The method of claim 2, A transparent protective layer having a refractive index smaller than that of the flat plate member is laminated on the surface of the flat plate member, and the light source unit is provided inside the mouse for manually moving the transparent protective layer on the surface of the flat plate member. And a light input from the bottom to arrange the spot light on the surface of the flat plate member. The method of claim 3, A transparent protective layer having a refractive index smaller than that of the flat plate member is laminated on the surface of the flat plate member, and the light source unit is provided inside the mouse for manually moving the transparent protective layer on the surface of the flat plate member. And a light input from the bottom to arrange the spot light on the surface of the flat plate member. The method of claim 4, wherein A transparent protective layer having a refractive index smaller than that of the flat plate member is laminated on the surface of the flat plate member, and the light source unit is provided inside the mouse for manually moving the transparent protective layer on the surface of the flat plate member. And a light input from the bottom to arrange the spot light on the surface of the flat plate member. The method of claim 4, wherein A transparent protective layer having a refractive index smaller than that of the flat plate member is laminated on the surface of the flat plate member, and the light source unit is provided inside the mouse for manually moving the transparent protective layer on the surface of the flat plate member. And a light input from the bottom to arrange the spot light on the surface of the flat plate member.