JPH10198500A - Coordinate input device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a highly stable and accurate coordinate input device capable of protecting a sensor from water drops or the like without interrupting the propagation of vibration. SOLUTION: The coordinate position of a vibration input point is calculated based on delay time generated up to the arrival of elastic wave vibration inputted to the surface of a vibration transmission board 8 by a vibration input pen at a vibration sensor 6c. An water drop preventing means 20 is arranged in the vicinity of the sensor 6c. The means 20 is formed by a hydro-phobic area 20a and a hydrophilic area 20b and both the areas 20a, 20b are linearly or concentrically applied to the board 8 so as to be alternately adjacently arranged. In the constitution, water drops 30 spilled on the board 8 in error are repelled on the area 20a and stacked on the area 20b, and since water drops are stacked/drained by repeating the stack/drainage, the sensor 6c is properly protected from water drops.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coordinate input device, in particular, an elastic wave vibration input from a vibration pen is detected by a plurality of sensors provided on a vibration transmission plate, and the vibration is input from the vibration pen to the vibration transmission plate. Based on the transmission time of the elastic wave vibration,
The present invention relates to an apparatus for detecting coordinates of a vibration input point by a vibration pen.

[0002]

2. Description of the Related Art As disclosed in Japanese Patent Publication No. 5-62771, a coordinate input device using ultrasonic waves detects a delay time of an elastic wave propagating on a tablet, which is an input surface, and calculates position coordinates. Since the calculation method is adopted, and no processing of the matrix-shaped electric wires or the like is performed on the tablet, it is possible to provide a device that is inexpensive in cost. Moreover, if a transparent plate glass is used for the tablet, a coordinate input device having higher transparency than other methods can be configured, and a pen computer or the like can be configured in combination with a flat panel display.

[0003]

The above-mentioned computer (handwritten electronic device) or the like is often used in a horizontal or inclined state, unlike a device using a CRT, such as coffee, tea, and water. It is necessary to take drip-proof measures because the possibility of spills is high.

However, in a coordinate input device of the type which detects elastic wave vibration and calculates coordinates as described above, if a member for protecting a sensor for drip-proofing is arranged on a propagation body, vibration propagation And the detection is adversely affected.

SUMMARY OF THE INVENTION Accordingly, the present invention has been made to solve such a problem, and it is possible to protect a sensor from water drops without obstructing vibration propagation, and to obtain a highly stable and highly accurate coordinate input device. Is to provide

[0006]

In order to solve the above-mentioned problems, a coordinate input device according to the present invention provides a delay time until an elastic wave vibration input on a vibration transmission plate by a vibration input means reaches a vibration detection means. In a coordinate input device for calculating a coordinate position of a vibration input point based on time, a drip-proof means including a first area and a second area having different characteristics with respect to water droplets is provided near the vibration detection means. Features.

With such features, the vibration detecting means (vibration sensor) can be protected from water droplets and the like, and a highly stable and highly accurate coordinate input device can be obtained.

The first region constituting the drip-proof means is formed of, for example, a hydrophobic material, and the second region is formed of a hydrophilic material. Further, the first and second regions are preferably provided in plural numbers, and are arranged on the vibration transmitting plate so as to be linearly or concentrically and alternately adjacent to each other.

In such a configuration, the water droplets spilled on the vibration transmitting plate by mistake are repelled in the hydrophobic region, and are collected in the hydrophilic region, and can be repeatedly collected and drained. So without disturbing vibration propagation
The vibration sensor can be appropriately protected from water droplets. In this case, if the widths of the first and second regions are made smaller as approaching the vibration detecting means, the drip-proof effect can be further enhanced.

Further, the drip-proof means may have a gap between the drip-proof means and the vibration transmitting plate. Also in this case, since the drip-proof means does not come into contact with the vibration transmission plate, the vibration sensor can be appropriately protected from water droplets without obstructing the propagation of vibration.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail based on an embodiment shown in the drawings.

[Embodiment 1] A coordinate input device using an elastic wave detects coordinates by measuring the group velocity and the phase velocity of a plate elastic wave as disclosed in Japanese Patent Publication No. 5-62771. Is known.

In the figure, reference numeral 1 denotes ROM, RA
An arithmetic control circuit that has a computer including an M and a counter, controls the entire apparatus, and calculates a coordinate position. A vibrator driving circuit 2 is connected to the arithmetic and control circuit 1,
The vibrator 4 in the pen 3 is driven via the vibrator drive circuit 2 by the pen drive signal output from the arithmetic and control circuit 1. The vibration generated by the vibrator 4 causes the pen tip 5 to vibrate.

Reference numeral 8 denotes a vibration transmission plate made of a transparent member such as an acrylic or glass plate.
Touching the vibration transmission plate 8 is performed. Actually, a region indicated by a symbol A indicated by a solid line in the drawing (hereinafter referred to as an effective area)
Input is performed by designating the inside with the vibration pen 3.

A vibration isolator 7 is provided on the outer periphery of the vibration transmitting plate 8 to prevent (reduce) the reflected vibration from returning to the central portion. The vibration sensors 6a to 6d for converting into signals are fixed.

The vibration detected by each of the vibration sensors 6a to 6d is input to a signal waveform detection circuit 9. The signal waveform detection circuit 9 computes a signal indicating that the vibration is detected by each of the vibration sensors 6a to 6d. Output to 1.

Behind the vibration transmission plate 8, there is disposed a display 11 such as a liquid crystal display capable of displaying in units of dots. Then, it is possible to display dots at the positions traced by the vibrating pen 3 by driving the display driving circuit 10 and see them through the vibration transmission plate 8 made of a transparent member.

In such a configuration, the vibrator 4 built in the vibrating pen 3 is driven by the vibrator driving circuit 2. The driving signal of the vibrator 4 is supplied as a pulse signal from the arithmetic and control circuit 1, amplified by the vibrator driving circuit 2 with a predetermined gain, and applied to the vibrator 4. Then, the electric drive signal is converted into mechanical ultrasonic vibration by the vibrator 4 and transmitted to the vibration transmission plate 8 via the pen tip 5.

Here, the vibration frequency of the vibrator 4 is selected to a value capable of generating a plate wave on the vibration transmission plate 8 such as glass. In addition, when the vibrator is driven, a mode of vibrating in the vertical direction in FIG. Further, by setting the vibration frequency of the vibrator 4 to the resonance frequency including the tip 5, efficient vibration conversion is possible.

The signal transmitted on the vibration transmitting plate 8 propagates on the vibration transmitting plate, and is detected by the sensor with a time delay corresponding to the propagation distance. A signal detected by each sensor is passed through a signal waveform detection circuit 9 through a circuit for detecting a group delay time based on the group velocity and a phase delay time based on the phase velocity. , The time from detection to detection by the sensor is measured. The measured group delay time Tg and phase delay time Tp
Is used to calculate the distance from the vibration input point to the sensor.

By calculating such a distance in each sensor, the coordinates of the input point can be calculated.

The elastic wave transmitted to the vibration transmitting plate 8 as described above is a plate wave, and has an advantage that the surface of the vibration transmitting plate is less susceptible to scratches, obstacles, and the like than surface waves. .

However, when the sensor can be constructed only on the input surface, when a cover made of rubber or the like is provided on the propagation body without a gap as a drip-proof mechanism, vibration is attenuated. , May affect detection.

An object of the present invention is to provide a drip-proof mechanism which does not affect the propagation of vibration. FIG. 2A shows an embodiment of a drip-proof mechanism provided around the sensor. I have. The drip-proof mechanism 20 is configured by alternately arranging stripe-shaped regions 20a and 20b, and is applied on the vibration transmission plate 8 constituting the propagation body in proximity to the sensor 6c.

In the figure, a so-called water-repellent material (fluorine resin or the like) is applied in a stripe shape to the region 20a, and a hydrophilic material (surfactant or the like) is applied to the region 20b. ing. At the interface of the region 20a, the water tends to flow as water droplets due to its high surface tension, whereas in the region 20b, the water tends to remain in this area because of the low surface tension at the interface. I do. For this purpose, the water droplet 30 on the propagation body 8 is
It is repelled from the area 20a, while it stays in the area 20b and flows downward.

Therefore, for example, if the coordinate input device is the sensor 6
When the liquid is spilled by mistake when the liquid is spilled by mistake when the liquid is spilled by mistake when the liquid is spilled accidentally when the liquid is spilled from the area 20a,
Since the water droplet 30 tends to flow downward in the region 20b,
As shown in the figure, even when the flow should reach the sensor 6c, it is accumulated in each region 20b, flows downward, and is discharged to the outside via the drain 32 formed in the vibration isolator 7. Therefore, by applying materials having different properties to the regions 20a and 20b, water droplets can be guided in a direction different from that of the sensor, and the sensor can be protected from water droplets.

The material of the regions 20a and 20b is water (liquid)
Since it is sufficient that the property of the interface with respect to the surface can be exhibited, it is only necessary to apply the film very thinly on the propagation body, and the vibration propagation is not affected.

The application pattern is not applied so that the stripe regions are parallel to the vibration transmitting plate 8 as shown in FIG. 2A, but is arranged obliquely as shown in FIG. The sensor may be better covered. Also, each area is not limited to straight stripes,
As shown in (C), a configuration in which the concentric circles are alternately arranged may be adopted.

The regions 20a and 20b adjacent to each other
The width (pitch) of may be determined according to the size of the corresponding water drop.
By adopting various pitches as shown in (D), which are not uniform as in (A) and (B), it is possible to cope with water droplets of various sizes. In particular, if the pitch is reduced as the distance from the sensor 6c is increased, large water droplets can be collected first, which is efficient.

The material of the region 20a is not limited to fluorocarbon resin, but has a hydrophobic group and is not particularly limited as long as it can be applied. The region 20b of the hydrophilic material is not particularly limited as long as it has a hydrophilic group that reduces the surface tension of water and the like.

In the above example, a coordinate input device using a plate wave has been described. However, it is apparent that the present invention is also effective in a coordinate input device using a surface wave, a longitudinal wave, and the like. It is.

In this embodiment, since the sensor 6c is located at the lower side, in FIG. 1, the drip-proof means 20 is provided only for the sensors 6c and 6d. However, it is obvious that the drip-proof mechanism of the various embodiments shown in FIG. 2 can be provided.

Although a part of the vibration isolator 7 is opened (32) for drainage, if the vibration isolator is formed on the rear surface only in this part, the influence of the end face reflection can be eliminated. Of course, when all the vibration damping materials are formed on the back surface, there is no need to provide an opening, and as shown in FIG. 2C, a drain receiver 32 ′ that prevents liquid from entering inside by an exterior or the like is provided. What is necessary is just to provide.

When the vibration transmitting plate has sufficient water repellency or hydrophilicity, only the material different from the surface of the transmitting plate is applied by utilizing the surface characteristics of the vibration transmitting plate. But it is good.

As described above, by alternately configuring regions having different surface states, it becomes possible to configure a drip-proof mechanism that does not affect the transmission of vibration.

[Second Embodiment] In an apparatus for detecting coordinates using vibration propagation, it is not desirable that an obstacle exists on the propagation path. In addition to configuring the drip-proof mechanism that does not affect vibration propagation as in the above-described embodiment, it is also possible to configure so as to have a drip-proof effect without contact.

FIG. 3 shows an example of this drip-proof mechanism. A water droplet guide member (guide plate) 40 that does not directly contact the vibration transmission plate is provided around the sensor 6c. By keeping the gap between the guide plate 40 and the vibration transmission plate 8 at an appropriate distance,
Water droplets can be guided in a direction different from that of the sensor 6c.

The gap distance depends on the size of the water droplet on the transmission plate 8 and is set to a distance at which the water droplet contacts the guide plate 40. A hydrophilic material may be applied to the guide plate 40, or a water-repellent material and a hydrophilic material may be applied alternately as described above. It goes without saying that the same processing may be performed on the transmission plate 8 side.

The water droplets transmitted on the transmission plate 8 come into contact with the guide plate 40, so that the water drops are prevented from traveling in the direction of the sensor 6c, and are guided toward the drain port 42.

With this configuration, it is possible to protect the sensor even if a large amount of water drops is applied.

[Embodiment 3] Instead of a single guide plate,
With a multi-stage configuration, the effect can be enhanced. FIG. 4 shows an example of such a case, and the guide plate includes three guide plates 40a, 40b, and 40c. Water drops
Since the first, second, and third guide plates 40a, 40b, and 40c do not stay in the gaps, they come into contact with one of the drip-proof plates and are more easily drained. Further, by making the gap between each guide plate and the vibration transmission plate 8 different from each other, it is possible to effectively act on water droplets having different sizes. Further, by determining the gap between the guide plates 40a, 40b, and 40c with respect to the diameter of the water droplet, more effective action can be obtained. In this case, of course, each gap may have a different size so as to correspond to various water droplet diameters.

Further, by making the gap between the guide plates narrower in the drainage direction, the guidance of water droplets can be made more effective. The water droplets that have come into contact with the guide plate have a property of flowing to the narrower side of the gap due to the capillary phenomenon. Therefore, by narrowing the width in the drainage direction, it is possible to guide the path of the water droplets in the drainage direction.

[0043]

As described above, according to the present invention,
In a coordinate input device that calculates a coordinate position of a vibration input point based on a delay time until elastic wave vibration input on a vibration transmission plate by a vibration input unit reaches a vibration detection unit,
In the vicinity of the vibration detecting means, a drip-proof means including a first area and a second area having different characteristics with respect to water droplets or a drip-proof means having a gap between the vibration transmission plate is provided. Thus, the vibration detecting means (vibration sensor) can be protected from water droplets or the like without obstructing the propagation of vibration, and a highly stable and highly accurate coordinate input device can be obtained.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing an overall configuration of a coordinate input device.

FIG. 2 is a configuration diagram showing various drip-proof mechanisms used in the coordinate input device.

FIG. 3 is a configuration diagram showing another embodiment of a drip-proof mechanism.

FIG. 4 is a configuration diagram showing still another embodiment of the drip-proof mechanism.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Arithmetic control circuit 2 Vibrator drive circuit 3 Vibration input pen 4 Vibrator 5 Pen tip 6a-6d Vibration sensor 7 Vibration-proof material 8 Vibration transmission board 9 Signal waveform detection circuit 20 Drip-proof mechanism 30 Water drop 40 Water drop guide plate

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hajime Sato 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Katsuyuki Kobayashi 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inside the corporation

Claims (7)

[Claims] 1. A coordinate input device for calculating a coordinate position of a vibration input point based on a delay time until an elastic wave vibration inputted on a vibration transmission plate by a vibration input means reaches a vibration detection means, A coordinate input device, wherein a drip-proof means including a first area and a second area having different characteristics with respect to water droplets is provided near the means. 2. The coordinate input device according to claim 1, wherein the first region is made of a hydrophobic material, and the second region is made of a hydrophilic material. 3. The coordinate input device according to claim 1, wherein a plurality of first and second regions are provided and are alternately arranged adjacent to each other. 4. The coordinate input device according to claim 1, wherein the first and second regions are arranged linearly or concentrically. 5. The coordinate input device according to claim 3, wherein the width of the first and second areas decreases as approaching the vibration detecting means. 6. A coordinate input device for calculating a coordinate position of a vibration input point based on a delay time until an elastic wave vibration input on a vibration transmission plate by a vibration input means reaches a vibration detection means, wherein: A coordinate input device, wherein drip-proof means having a gap between the vibration transmission plate and the vibration transmission plate is provided near the means. 7. The coordinate input device according to claim 6, wherein said drip-proof means comprises one or a plurality of water droplet guiding members.