JPH08234895A - Coordinate input method and device - Google Patents

Abstract

PURPOSE: To provide the method and device for inputting coordinates which enables coordinate information to be inputted while simultaneously instructing plural coordinate positions over a wide range. CONSTITUTION: Light from a light emitting element 2 is made incident on one end of each of plural optical fiber cores 11 arranged at fixed intervals in lateral and longitudinal axial directions, and the intensity of light passed through the respective optical fiber cores 11 is detected by light receiving elements 3 provided at the respective other ends of these plural optical fiber cores. Corresponding to the quantity of light detected by these light receiving elements 3, the optical fiber core, to which pressure almost vertical to the lengthwise direction of the optical fiber core is impressed, is specified and the coordinates of that position, where pressure is impressed, are calculated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coordinate input method and apparatus for detecting and outputting coordinate information of a position designated on a coordinate input surface.

[0002]

2. Description of the Related Art There are the following coordinate input methods in a conventional coordinate input device.

In the resistance film system (pressure sensitive system), two or more glass plates or resin films having transparent resistors are stacked to form a coordinate input surface, and a coordinate input surface is formed on the surface.
These two transparent resistors contact each other. At this time, by energizing these resistors and detecting a change in their resistance value, the contact point is determined and converted into its position coordinates.

The capacitive coupling method, the electromagnetic induction method, and the electromagnetic transfer method are coordinate input by one or two or more glass plates or resin plates having a transparent electrode pattern in a line or loop coil shape in the x and y directions. Make up a surface. By processing the signal on the electrode pattern detected on the coordinate input surface via the dedicated pen and the electromagnetic wave, the transparent electrode pattern closest to the position designated by the dedicated pen is specified. As a result, the pointed position on the coordinate input surface is specified and converted into coordinate information indicating the position.

In the coordinate input device using ultrasonic waves, a plurality of vibration detecting means (sensors) are installed on the tablet which is the input surface, and the vibration input means (vibrating pen) detects the vibration input on the tablet surface. To do. Then, the distance between these sensors and the vibrating pen is calculated from the time required for the vibration to propagate and the propagation speed, and the input coordinates are detected based on the distance.

In the stylus pen method, a stylus pen brought into contact with a CRT detects a scanning signal of the CRT, a position on a raster pattern is specified from the detected scanning timing, and the designated position coordinate is detected. Is a method of specifying.

As an optical type, there is a light blocking type touch panel in addition to this. This is because a light beam of infrared rays or the like is stretched around the display surface of the display like a mesh, and touch input is detected by blocking it with a finger, depending on which light receiving unit detects light blocking, The touched coordinates are specified.

[0008]

However, the above-mentioned conventional coordinate calculation method has the following problems. (1) Input is not possible without a dedicated pen ... (2) Coordinate input accuracy is poor and resolution is poor ... (3) Multiple coordinates cannot be input simultaneously in a wide range ... (4) It is not possible to directly detect the input state (for example, writing pressure) (needs another means for detection) ...
,, If supplemented with (3) above, for example, 2 mm □
Area divided by the resolution of the coordinate input device (for example, if the resolution is 0.2 mm, 2 ÷ 0.2 = 10,
There is no function to output as coordinate data of 10 × 10 = 100 points). It should be noted that this function does not include a function of softening so as to output a line segment or a region sandwiched by a plurality of points by designating two points or three points at the same time.

It is desired that such a coordinate pointing device be provided with various coordinate pointing functions for use in personal computer equipment or the like. For example, character recognition based on a plurality of stroke data input at high resolution to perform character input, without using a special coordinate indicator,
It is possible to select an object by pointing with a finger or the like. Also, if you can detect the writing pressure (creating a crush of the tip of the brush) and the writing speed, you can input characters and pictures with the feeling of a brush / paint brush, sometimes you can input the state of pressing with your fingers or the entire palm as a use in games, It is obvious that the application range of these coordinate input devices will be expanded.

However, in the conventional coordinate input device, it was impossible to actually realize all the above-mentioned functions by one coordinate input device. Therefore, we use (1)-
The objective of the present invention is to solve the above-mentioned problem by focusing on a light-shielding touch panel having the least problem (4) and expanding its function.

The principle of this light-blocking coordinate detection is shown in FIG.
Will be explained.

In FIG. 2, a light beam 4 which extends around a space 3 to 8 mm above the display 5 is emitted from the light emitting element 2 and detected by the light receiving element 3. Here, finger 1 is indicator 5
When touching the coordinate input surface of the upper surface, the light beam 4 is blocked by the finger 1, the amount of light incident on the corresponding light receiving element 3 is reduced, and the output thereof is reduced. A plurality of sets of the light-emitting element 2 and the light-receiving element 3 facing each other in this way are provided on the x-axis and the y-axis, respectively, and the light-receiving element 3 in which the light beam 4 is blocked is specified, so that the finger 1 touches Output the two-dimensional coordinates of the position.

However, considering the principle of this light blocking method, the problems (2) and (4) cannot be solved. In (2), since the light beam itself has a certain spread, when two adjacent light emitting elements 2 and light receiving elements 3 are brought close to each other, the light beam from the adjacent light emitting element 2 is received. Detection sensitivity decreases. For this reason, these adjacent light emitting elements cannot be brought closer to each other to some extent. Further, in order to solve such a problem, in order to make a light beam that is narrowed down (parallel light that is difficult to spread), not only the light emitting element 2 (LED or LD) is changed, but also the light emitted from the light emitting element 2 is changed. A condensing lens for condensing is required. If such a lens is used, the width is taken by itself, and it is impossible to bring the light emitting elements 2 closer to each other to improve the resolution. Moreover, another problem occurs because the light beam 4 passes several mm above the display 5, and it is meaningless to increase the resolution due to that problem.

That is, this is a problem of a displacement (generally called parallax) between the display 5 and the touch surface. Consider a case where the light blocking touch panel integrated with the display 5 is used when viewed from an angle. Even if the finger 1 is used to point the object displayed on the display 5, the position on the surface actually touched by the finger 1 and the position where the light beam 4 is shielded are deviated. This is the upper threshold (1
The parallax is improved by passing the light beam 4 within (mm), but it is difficult considering the width of the light emitting element 2. Further, even though the parallax is several mm, if the resolution of the coordinate input section is 1 mm or less, the resolution is meaningless. Therefore, the problem (2) above is difficult to solve in principle.

In addition, even if the tip is sharp, the pointing device (including a finger) having a thickness or thickness cuts off the light beam 4 which is not intended to be directed, which causes an erroneous input. May be. As shown in FIG. 2, the width (7) of the blocking area of the light beam 4 is wider than the length (6) of the area directly touched by the finger 1. Therefore, as shown in FIG. 3, a light-blocking type tablet provided with an erroneous operation prevention barrier 8 is also proposed (Japanese Patent Laid-Open No. 6-175781). FIG.
In the above, the barrier 8 is formed in a lattice shape so that the finger 1 does not enter the passage area of another light beam 4. However, as can be seen from FIG. 3, the resolution of this tablet is determined by the lattice pitch of these barriers 8, and
Can only obtain a resolution greater than the thickness of.

Next, regarding the problem (4) (the input state cannot be detected), the above-described light blocking method detects that the light beam 4 is blocked by an opaque pointing tool such as a finger. Therefore, it can only have binary information of 0 or 1, or on or off. Therefore, this also cannot solve the above-mentioned problems.

The present invention has been made in view of the above conventional example, and an object of the present invention is to provide a coordinate input method and an apparatus therefor capable of pointing a plurality of coordinate positions simultaneously and inputting coordinate information over a wide range. To do.

Another object of the present invention is to provide a coordinate input method and apparatus for inputting coordinate information without using a dedicated pen.

Another object of the present invention is to provide a coordinate input method and apparatus which can improve the coordinate input accuracy and obtain high resolution.

Another object of the present invention is to provide a coordinate input method and apparatus capable of detecting the input state as well as the designated coordinate position.

[0021]

In order to achieve the above object, the coordinate input device of the present invention has the following configuration.
That is, a plurality of optical fiber cores arranged at regular intervals in the horizontal axis direction and the vertical axis direction, a light incidence means for entering light from one end of the plurality of optical fiber cores, and the plurality of optical fiber cores. At each of the other ends, a light detection unit that detects the intensity of light that has passed through the optical fiber core, and a pressure substantially perpendicular to the longitudinal direction of the optical fiber core according to the amount of light detected by the light detection unit. And a coordinate determining unit that specifies the applied optical fiber core and obtains the coordinates of the portion to which the pressure is applied.

In order to achieve the above object, the coordinate input method of the present invention comprises the following steps. That is, a coordinate input method in which a position to which a pressure is applied is detected to input coordinates, and one optical fiber core is bent to be arranged in a two-dimensional shape, and the first end of the optical fiber core is arranged. The light from the optical fiber core, the step of detecting the light intensity from the first end or the second end of the optical fiber core, and the optical fiber based on the detected light intensity. And a step of calculating the position where the pressure is applied to.

[0023]

In the above structure, light is incident from one end of the plurality of optical fiber cores arranged at regular intervals in the horizontal axis direction and the vertical axis direction, and at the other end of each of the plurality of optical fiber cores, The intensity of light that has passed through the optical fiber core is detected. According to the amount of light detected in this way, the optical fiber core to which a pressure substantially perpendicular to the longitudinal direction of the optical fiber core is applied is specified, and the coordinates of the location where the pressure is applied are obtained.

According to another aspect, data indicating the degree of the applied pressure is added to the coordinate value and output.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will now be described in detail with reference to the accompanying drawings.

[First Embodiment] FIG. 1 is a diagram showing the structure of a coordinate input device according to an embodiment of the present invention.

A plurality of rows of optical fiber cores 11 for the y-axis are arranged in the input section, and a light emitting element 2 such as an LED (light emitting diode) or an LD (semiconductor laser) is provided from one end of each optical fiber core 11. Light from a plurality of optical fiber cores is simultaneously incident on the plurality of optical fiber cores. Then, at the opposite ends of the optical fiber cores 11,
The light transmitted through the inside is detected by the light receiving element 3 (CCD or photodiode). A configuration similar to these optical fiber core groups for the y-axis is arranged in the x-axis direction (not shown), and the two-dimensional optical fiber core groups in the x-axis and y-axis directions configure a two-dimensional coordinate detection unit. are doing.

FIG. 4 is a diagram showing a cross-sectional shape of the input portion of the coordinate input device of this embodiment, showing a state in which a part of the input portion is pressed by the finger 1. In this input section, optical fiber cores 11 through which light is transmitted are arranged at equal intervals, and a buffer section 12 is formed around these optical fiber cores 11 using a clad material having a smaller bending rate than the core material. Has been done. Thereby, the light passing through the inside of the optical fiber core 11 is confined inside the optical fiber core 11.

Here, as shown in FIG. 4, when an external force (pressing force) is applied to the optical fiber core 11, the bending rate of the optical fiber core 11 changes, and the polarization amount of the light propagating through the optical fiber core 11 changes. Changes. However, in order to directly detect this change in the polarization amount, a complicated detection circuit or the like is required, which is not desirable for a low cost and simple coordinate input device.
Rather, it is easier to detect the change in the amount of propagating light due to the deformation (bending or crushing) of the optical fiber core 11. When the optical fiber core 11 is bent, birefringence and transmission loss occur in the optical fiber core 11. In the case of a POF-based plastic optical fiber core, when a pressure is applied, the core cross-sectional shape is crushed and deformed from a circular shape to an elliptical shape, and the same effect as when the fiber is bent is produced.

The coordinate input device of this embodiment employs a method of detecting the occurrence of light transmission loss due to bending (and crushing) of the optical fiber core 11. When the optical fiber core 11 is bent, the guided mode becomes the radiation mode, and light is emitted to the outside of the optical fiber core 11. This is called bending loss and generally increases as the difference in refractive index between the fiber core 11 and the clad (buffer portion) 12 decreases.

FIG. 5 is a diagram showing the result of calculation of the bending loss of a general step index type optical fiber.

As shown in FIG. 5B, the diameter of the optical fiber is 2a, its length is z, and its radius of curvature is R. Let P (0) be the optical power incident on this optical fiber, and P be the propagated optical power detected at the output of the fiber.
Incident light power P (0) for bending when (z)
The measurement result of the ratio between the detected light power P (z) and the detected light power P (z) is shown in FIG.
Is shown in.

From this, it is understood that when the bending radius R of the optical fiber core 11 is very small, on the order of several mm, the light loss becomes remarkable. A microbender sensor (FIG. 6) utilizing this has been proposed as a sensor for pressure, sound waves, strain, and the like. When the optical fiber core 11 made of plastic (POF) is used as in the coordinate input device of the present embodiment, the thickness of the buffer portion 12 is reduced as shown in FIG. All you have to do is configure it so that it is easy to collapse.

Based on the above configuration, the principle of detecting the pressed position coordinates will be described. As shown in FIG. 1, all output levels of a plurality of light receiving elements 3 provided are detected. And
When the light receiving element 3 having a lowered light amount level is detected, the optical fiber core 11 to which the pressure is applied is specified in association with the light receiving element 3. The number of optical fiber cores 11 specified in this way may be plural. In that case, the arithmetic control unit processes the data with a gradation proportional to the applied pressure depending on how the detection level in each optical fiber core 11 is lowered, and the optical fiber core 11 positioned at the center thereof is processed. Should be specified.

Further, according to the same principle, the optical fiber 11 whose light quantity has changed is specified also in the other x-axis direction.
Assuming that pressure is applied to the intersection point of the optical fiber cores 11 in the x-axis and y-axis directions thus specified, the intersection point position is converted into position coordinates and output.

FIG. 7 is a block diagram showing the schematic arrangement of the coordinate position detecting / calculating section of the coordinate input device (optical fiber tablet) of this embodiment.

The light receiving elements 3 are provided in the same number as the number of rows of the optical fiber cores 11 arranged at the pitch of the required resolution. The detection signals output from these light receiving elements 3 are
It is sequentially selected by the selector 23 in accordance with the instruction of the arithmetic control unit 21 and sent to the A / D converter 22. The A / D converter 22 converts the detection signal from each of the light receiving elements 3 into 4-bit (16 gradations) digital data and outputs it as data of the selected light receiving element 3 to the arithmetic control unit 21. The arithmetic control unit 21 selects data having a predetermined reference value or less (data in which the light amount has decreased by a predetermined amount or more) and obtains pressure data of the external pressure applied to the optical fiber core 11 based on this data.

Although FIG. 7 shows only the coordinate detection and calculation unit in the y-axis direction, similar processing is performed in the x-axis direction. Coordinate data including pressure data is obtained based on the thus obtained data in both axial directions.

The feature of the coordinate input device of this embodiment is that the resolution that can be input is determined by the pitch at which the optical fiber cores 11 are arranged. Since the diameters of the optical fiber cores 11 themselves are about 100 μm, by arranging the optical fiber cores 11 more finely, a coordinate input device with high resolution can be obtained.

Further, as is clear from FIG. 7, even when a plurality of coordinate positions are designated at the same time, those position information can be inputted at the same time. Further, each coordinate data can be provided with pressure data, and this pressure data can be adopted as a command associated with the instructed position such as menu selection or file opening.

FIG. 8 is a diagram showing an example in which coordinate data including the pressure data thus obtained is displayed three-dimensionally.

In FIG. 8, the x- and y-axis directions indicate coordinate positions, and the z-axis direction indicates pressure distribution. Since the distribution of pressure data can be obtained with such a high resolution, for example, by standing on a tablet, applications such as correcting the posture from the distribution of pressure data detected by the pressing force on the sole of the foot, and virtual -It can be applied to the sensor of reality equipment or various game machines.

FIG. 9 is a flow chart showing the coordinate position detecting process executed by the arithmetic control unit 21 of the coordinate input device of this embodiment. The program for executing this process is ROM.
It is stored in 211 and is executed under the control of the CPU 210.

First, in step S1, the index i is initialized to "0", and in step S2, the value of i is output to the selector 23 to select the data from the i-th light receiving element 3 for A / D conversion. Input to the container 22. Then step S
In 23, 4 which is A / D converted by the A / D converter 22
Input bit digital data. Then step S4
Then, it is checked whether the input 4-bit data value is smaller than a predetermined value. If it is less than or equal to a predetermined value, step S5
Then, the 4-bit data and the value of i at that time are stored in the memory (RAM 212).

In step S6, the value of i is incremented by 1,
The value of i showing the result is the light receiving element 3 in the x-axis or y-axis direction.
See if it is equal to the number of. If not, the process returns to step S2 and the above-mentioned processing is executed. Thus x
When the data from all the light receiving elements 3 in the axial or y-axis direction are input, the process proceeds from step S7 to step S8, and the RAM 2
4-bit data stored in 12 and the corresponding i
From the value of, the coordinate position designated on the coordinate input surface and the corresponding 4-bit data (gradation data) are output. By executing this process in both the x-axis direction and the y-axis direction, the x and y coordinates of the designated coordinate position can be obtained.

If a plurality of positions are designated at the same time, the plurality of position coordinates are output at the same time, and gradation data is attached to each of the coordinate data and output.

[Second Embodiment] Next, a description will be given of a second embodiment of the present invention, in which a tablet is formed by using an optical fiber of silica (glass).

FIG. 10 is a diagram showing an example in which a mechanism (micro bender) for giving a curvature to the optical fiber is provided so that the optical fiber is bent by pressure.

In this micro-bender, as shown in FIG. 10, the transparent rigid body 13 is arranged so as to be orthogonal to the optical fiber core 11. The transparent rigid body 13 may have a cylindrical shape as shown in FIG. 10 as long as the transparent rigid body 13 is not deformed at the location where the external pressure is applied and the optical fiber core 11 is bent around it. It may be arranged in a dot shape above and below 11.

The advantage of using such a silica type optical fiber core 11 is that the amount of light received by the light emitting element 3 can be made small in advance because the transmission loss is originally smaller than that of the plastic type optical fiber. . But,
Since the structure of the coordinate input unit is complicated, its thickness increases, and the cost increases, it is desirable to use the coordinate input unit properly according to the application.

[Third Embodiment] FIG. 11 is a block diagram showing a configuration example of a coordinate input device (tablet) using another optical fiber core 31.

When the optical fiber core is bent, the transmission mode of the light is changed. Polarization-preserving single-mode optical fiber core 31 is irradiated with one of two modes of orthogonal and polarized light, and when the optical fiber core 31 is bent (pressed), one mode is changed. Convert to another mode. Since the transmission speed of light in each mode is different, there is a difference in the time from the incident end of the optical fiber core 31 to the output end. Using this characteristic, the point where the optical fiber 31 is bent (the point where it is pressed) is detected. The position of this bending point can be detected by separately preparing optical fibers of the same length and detecting the phase shift in these optical fibers by the heterodyne method. In such an optical fiber 31, since the transmission speed of light changes after the occurrence point of bending, the phase change of light causes
The bending occurrence point can be simply determined.
As described above, the optical fiber core 31 of the present embodiment may have the two transmission modes as described above.

The optical fiber core 31 need not be of a transmissive type, but may be of a reflective type utilizing the backscattering of light. In that case, the light receiver 24 is provided at the same optical fiber end as the light emitting element 2. And. When external pressure is applied to the optical fiber 31, its refractive index becomes spatially non-uniform, which causes large light scattering (Rayleigh scattering). Of the light thus scattered, the component whose scattering direction is within the critical angle of the optical fiber is transmitted to the front and back of the optical fiber as a guided mode (usually there is a certain amount of backscattering even without external pressure). ). The optical power returning to the incident end due to the backscattering of the optical fiber is given as a function of the time measured from the incident time of the optical pulse, so the backscattered light intensity is detected and the position is evaluated from the peak ( OTDR
Law).

Since the feature of the third embodiment can be realized by the construction of one optical fiber core 31, one set of the light emitting element 2 and the light receiver 24, the construction is simpler than that of the above-mentioned embodiment. Become.

The present invention may be applied to a system composed of a plurality of devices or an apparatus composed of one device. The present invention can also be applied to the case where it is achieved by supplying a program for implementing the present invention to a system or an apparatus.

As described above, according to this embodiment, it is possible to provide a coordinate input device having high resolution and requiring no special pen.

Further, since it is possible to input a plurality of points at the same time and coordinate data can be added to the coordinate position,
Not only the coordinate position can be specified, but also the function associated with the position specification can be instructed at the same time. As a result, the present invention can be applied to, for example, game machines and virtual reality.

[0058]

As described above, according to the present invention, there is an effect that a plurality of coordinate positions can be simultaneously instructed over a wide range to input coordinate information.

Further, according to the present invention, it is possible to input coordinate information without using a dedicated pen.

Further, according to the present invention, there is an effect that the coordinate input accuracy can be improved and a high resolution can be obtained.

Further, according to the present invention, the input state can be detected together with the designated coordinate position.

[0062]

[Brief description of drawings]

FIG. 1 is a diagram showing a structure of a coordinate input device according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating the principle of a conventional light blocking tablet.

FIG. 3 is an explanatory diagram of a tablet improved from a conventional light blocking method.

FIG. 4 is a diagram showing a structure of an input unit of the optical fiber tablet according to the present embodiment.

FIG. 5 is a diagram showing a result of calculation of bending loss of a general step index type optical fiber.

FIG. 6 is a diagram showing a microbender sensor.

FIG. 7 is a block diagram showing a schematic configuration of a coordinate position detection / calculation unit of the coordinate input device (optical fiber tablet) of the present embodiment.

FIG. 8 is a diagram showing an example in which coordinate data including pressure data output from the coordinate input device of the present embodiment is displayed three-dimensionally.

FIG. 9 is a flowchart showing a process in an arithmetic control unit of the coordinate input device according to the present embodiment.

FIG. 10 is a diagram showing an example in which a mechanism (micro bender) for giving a curvature to the optical fiber is provided so that the optical fiber is bent by pressure.

FIG. 11 is a block diagram showing a configuration example of a coordinate input device (tablet) using another optical fiber core.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 finger 2 light emitting element 3 light receiving element 4 light beam 11 optical fiber core 12 clad (buffer section) 13 transparent rigid body 21 arithmetic control section 22 A / D conversion section 23 selector 24 light receiver 210 CPU 211 ROM 212 RAM

 ─────────────────────────────────────────────────── ─── Continued front page (72) Inventor Hajime Sato 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Katsuyuki Kobayashi 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Incorporated (72) Inventor Yuichiro Yoshimura 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (9)

[Claims] 1. A plurality of optical fiber cores arranged at regular intervals in a horizontal axis direction and a vertical axis direction, a light incident means for injecting light from one end of the plurality of optical fiber cores, and the plurality of light rays. At each end of the fiber core,
A light detecting means for detecting the intensity of light passing through the optical fiber core, and an optical fiber core to which a pressure substantially perpendicular to the longitudinal direction of the optical fiber core is applied according to the amount of light detected by the light detecting means. And a coordinate determining means for determining coordinates of a portion to which the pressure is applied, and a coordinate input device. 2. The coordinate input device according to claim 1, wherein the coordinate determining means has a pressure detecting means for detecting a pressure applied to the optical fiber according to the detected light amount. . 3. The coordinate input device according to claim 2, further comprising output means for outputting data indicating the degree of pressure detected by the pressure detecting means together with the coordinates. 4. The coordinate input device according to claim 1, wherein the light detecting means includes a plurality of light receiving elements. 5. The light detecting means includes a selecting means for sequentially selecting one of the plurality of light receiving elements, and an A / D conversion for converting an analog signal from the light receiving element selected by the selecting means into a digital signal. The coordinate input device according to claim 4, further comprising means. 6. A pressure-sensing means in which one optical fiber core is bent to be arranged in a two-dimensional shape, an incidence means for injecting light from a first end of the optical fiber core, and the optical fiber core. A light detecting means for detecting the light intensity from the first end portion or the second end portion, and a position where pressure is applied to the optical fiber based on the light intensity detected by the light detecting means. And a position calculating means for calculating. 7. A coordinate input method for detecting coordinates where pressure is applied and inputting coordinates, wherein a plurality of optical fiber cores are arranged at regular intervals in a horizontal axis direction and a vertical axis direction. A step of injecting light, a step of detecting the intensity of light that has passed through the optical fiber cores at the other ends of the plurality of optical fiber cores, and a longitudinal direction of the optical fiber cores depending on the detected light amount. Specifying the optical fiber core to which a vertical pressure is applied and obtaining the coordinates of the location to which the pressure is applied. 8. The method further comprises the step of detecting the pressure applied to the optical fiber according to the detected light amount, and outputting data indicating the degree of the detected pressure together with the coordinates. The coordinate input method according to claim 7. 9. A coordinate input method for detecting a position to which a pressure is applied and inputting coordinates, wherein one optical fiber core is bent and arranged in a two-dimensional shape, and the first optical fiber core The step of injecting light from one end, the step of detecting the light intensity from the first end or the second end of the optical fiber core, and based on the detected light intensity, Calculating a position where pressure is applied to the optical fiber, the coordinate input method.