JP2000347806A - Coordinate input pen - Google Patents

Abstract

PROBLEM TO BE SOLVED: To maintain a stable light emitting state for a long time by providing a light emitting means built in a pointer for emitting light and light transmissive members, which cover the light emitting means, detachable from the pointer. SOLUTION: A pointer 4 is composed of a light emitting element 41 such as semiconductor laser for emitting a light beam or LED for emitting infrared light, a light emission control part 42 for driving and controlling that light emission, a power source part 44 and a cap composed of detachable light transmissive members for covering the light emitting element 41 or the like. The light transmissive member is provided with the first light transmissive member having a concave lens for scattering on a coordinate input picture at least and the second light transmissive member having convex lens characteristics for convergence on the coordinate input picture and a zoom lens mechanism is composed of the respective first and second light transmissive members. Besides, concerning the pointer 4, the light emitting element 41 is covered with the cap composed of the respective first and second light transmissive members. Thus, the coordinate input of high resolution and high performance is enabled.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a coordinate input pen for generating a light spot by irradiating a predetermined position on a coordinate input screen with light and inputting coordinates corresponding to the light spot.

[0002]

2. Description of the Related Art A CCD area sensor is used as a coordinate input device used to control a computer connected externally or to write characters, figures, etc. by directly inputting coordinates on a large display screen with a pointing tool. An image of a light spot on the screen using an image sensor or a linear sensor, image processing such as using barycentric coordinates or pattern matching is performed, and a coordinate value is calculated and output. Devices using an analog device that can obtain an output voltage corresponding to a position) are known.

[0003] For example, Japanese Patent Publication No. 7-76902 discloses an apparatus for detecting a coordinate by imaging a light spot formed by a parallel beam of visible light with a video camera and simultaneously transmitting and receiving a control signal using infrared diffused light. ing. In addition, Japanese Unexamined Patent Publication No.
Japanese Patent Publication No. 274266 discloses an apparatus for detecting coordinates using a linear CCD sensor and a special optical mask.

On the other hand, Japanese Patent No. 2503182 discloses that PS
Regarding an apparatus using D, a configuration and a method of correcting output coordinates are disclosed.

[0005]

In a pointing device of a conventional coordinate input device, a light emitting element of a light emitting portion, for example, LE
D, There is no particular provision regarding the structure around components such as a semiconductor laser, and the light-emitting component emits light, directly projects on the projection screen without passing through other members, or the screen surface which is directly the input screen , And inputting instructions. However, especially when inputting coordinates by bringing the pointing tool into contact with the screen surface, a light emitting element such as LE
D transparent sealing resin wears due to friction with the screen,
A change in the amount of light emitted from the LED due to a change in the shape of the lens and a change in the light emission distribution have caused inconveniences such as a reduction in coordinate detection accuracy. Conventionally, a configuration in which a light-emitting portion is provided with a filter has been proposed.However, the filter itself is a part of a light-emitting element as a light-emitting member, which is an optical component that is not allowed to be damaged. Not disclosed. Further, when the wear has progressed, it is necessary to replace the light emitting member such as the LED or the filter, and further, the entire indicator.

At the same time, repetition of contact in a worn and damaged state causes damage to the screen.

On the other hand, for presentation purposes,
It is often used as a large input device in combination with a large display device or alone, and there are different use modes for directly touching the input screen and inputting instructions as a pen, and for remotely pointing as a pointer. In addition, it is necessary to change the light emission irradiation state of the pointing device so as to generate an optimum light spot in each mode.

The present invention has been made in view of the above problems, and maintains a stable light emitting state for a long time.
An object of the present invention is to provide a coordinate input pen that enables high-resolution and high-performance coordinate input.

[0009]

A coordinate input pen according to the present invention for achieving the above object has the following arrangement.
That is, a coordinate input pen for generating a light spot by irradiating light to a predetermined position on a coordinate input screen and inputting a coordinate corresponding to the light spot, wherein the light emitting means is built in the pointing device and emits light. And a translucent member that covers the light emitting means and is detachable from the pointing device.

Preferably, the light-transmitting member is made of P
It is composed of a transparent resin material containing at least one of MMA (methacrylic resin), AS (styrene, acrylonitrile copolymer), PS (polystyrene), PC (polycarbonate), and epoxy resin.

Preferably, the light-transmitting member has a substantially hemispherical dome shape having a constant thickness.

[0012] Preferably, the translucent member is a translucent member having a concave lens that diffuses to the coordinate input screen.

Preferably, the light-transmitting member is a light-transmitting member having a convex lens characteristic for condensing light on the coordinate input screen.

Preferably, the light-transmitting member has a first light-transmitting member having a concave lens that diffuses to the coordinate input screen, and a second light-transmitting member having a convex lens characteristic for condensing light on the coordinate input screen. A light-transmitting member, wherein the first light-transmitting member has a substantially hemispherical dome shape, and the second light-transmitting member has a cylindrical shape, and is attached to the light emitting means. The second light-transmitting member is mounted on the first light-transmitting member.

Preferably, the light-transmitting member has a first light-transmitting member having at least a concave lens that diffuses to the coordinate input screen, and a second light-transmitting member having a convex lens characteristic for condensing light on the coordinate input screen. A light transmitting member, wherein the first light transmitting member and the second light transmitting member constitute a zoom lens mechanism.

Preferably, the translucent member is composed of a plurality of exchangeable translucent members having different irradiation optical characteristics.

[0017]

Embodiments of the present invention will be described below in detail with reference to the drawings.

First, a schematic configuration of an optical coordinate input device according to the present invention will be described with reference to FIG.

FIG. 1 is a diagram showing a schematic configuration of a coordinate input device according to the present embodiment.

The coordinate input device is roughly divided into an indicator 4 for forming a light spot 5 on a screen 10 as a coordinate input surface, and a coordinate detector 1 for detecting the position coordinates of the light spot 5 on the screen 10 and the like. Consists of FIG. 1 shows a screen 10 as an output device together with those configurations.
2 shows a projection display 8 for displaying an image, position coordinates, and the like.

The coordinate detector 1 includes a coordinate detection sensor unit 2 and
The controller 3 includes a controller 3 for controlling the coordinate detection sensor unit 2 and calculating coordinates, a light receiving element 6, and a signal processing unit 7. The controller 3 detects the coordinate position of the light spot 5 on the screen 10 and a control signal corresponding to the state of each switch of the pointing tool 4 described later, and communicates the information to an external connection device (not shown) by the controller 3. ing.

The projection display device 8 includes an image signal processing section 81 to which an image signal from a display signal source, which is an external connection device such as a host computer (not shown), is input, a liquid crystal panel 82 controlled by the image signal processing section 81, Lamp 83, mirror 8
4. An illumination optical system including a condenser lens 85, and a projection lens 86 for projecting an image of the liquid crystal panel 82 onto the screen 10,
Can be displayed. Since the screen 10 has an appropriate light diffusing property in order to widen the observation range of the projected image, the light beam emitted from the pointing tool 4 is also diffused at the position of the light spot 5, and the position on the screen and A part of the light diffused at the position of the light spot 5 enters the coordinate detector 1 irrespective of the direction of the light beam.

With such a configuration, by inputting character information and line drawing information on the screen 10 by the pointing tool 4 and displaying the information on the projection display device 8, it is as if "paper and pencil". In addition to enabling input / output of information in a relationship, it is configured such that input operations such as button operation and icon selection can be freely performed. <Detailed Description of Pointing Tool 4> FIG. 2 is a diagram showing a detailed configuration of the pointing tool of the present embodiment.

The pointing tool 4 is a light emitting element 4 such as a semiconductor laser that emits a light beam or an LED that emits infrared light.
1, a light emission control unit 42 for driving and controlling the light emission, a power supply unit 44, operation switches 43A to 43D, a power supply unit 44 such as a battery, and a cap 46 made of a detachable translucent member that covers the light emitting element 41. And built-in. The light emission control unit 42 changes the state of the operation switches 43A to 43D.
Light emission control in which a control signal is superimposed is performed by ON (ON) / OFF (OFF) of light emission and a modulation method described later.
The cap 46 is a main cylinder of the present invention, and will be described later in detail with reference to FIG.

FIG. 3 is a diagram showing an operation mode of the pointing device of the present embodiment.

The switches A to D correspond to the switch 43A of FIG.
~ 43D. In FIG. 3, “light emission” corresponds to a light emission signal (coordinate signal), and “pen down” and “pen button” correspond to control signals.

The operator holds the pointing device 4 and holds the screen 1
Point its tip at zero. At this time, the switch 43A is arranged at a position where the thumb naturally touches, and when pressed, the light beam 45 is emitted. As a result, the light spot 5 is generated on the screen 10, and the coordinate signal starts to be output by a predetermined process. However, in this state, the pen down and pen button control signals are OFF. For this reason, on the screen 10, only the indication of the position indicated to the operator by the movement of the cursor or the switching of the highlight of the button is performed.

By pressing switches 43C and 43D arranged at positions where the forefinger and the middle finger naturally touch, the pen down and pen button control signals become signals superimposed on the light emission signal as shown in FIG. . That is, by pressing the switch 43C, a pen-down state is established, and screen control such as starting input of characters and line drawings and selecting and determining a button can be executed. Switch 43
By pressing D, the state of the pen button is established, and it is possible to correspond to another function such as calling a menu. This allows the operator to quickly and accurately draw characters and figures at any position on the screen 10 with one hand,
By selecting buttons and menus, it can be operated lightly.

A switch 4 is provided at the tip of the pointing device 4.
A switch 3B is provided and operates when the pointing tool 4 is pressed against the screen 10. The operator grips the pointing device 4 and touches the tip of the pointing device on the screen 10.
, A pen-down state is established, so that a natural pen input operation can be performed without performing extra button operations.

In the present invention, the portion of the switch 43B that comes into contact with the screen 10 is formed by a cap 46. The switch 43A has a role of a pen button. Of course, if the switch 43A is pressed without pressing the screen, only the cursor can be moved. Actually, the operability and accuracy are much better when the characters and graphics are input directly from the screen than when the characters or figures are input from the screen. In the present embodiment, even if the user is away from the screen by using the four switches, or immediately before, a natural and comfortable operation can be performed, and the user can use the switch depending on the case. I have. Furthermore, if it is used only for direct input (not used as a pointer), a diffused light source may be used instead of a light beam. Therefore, it is possible to use an LED which is cheaper and has a longer life than a semiconductor laser. However, when the tip of the pointing device 4 is used so as to directly contact the screen 10, the problem to be considered is a problem related to abrasion due to friction between the tip of the pointing device 4 and the screen 10. In addition, the projection characteristic of light from the pointing device 4 differs between the case where the pointer is used away from the screen and the case where input is performed by directly touching the screen. This will be described later in the description of the cap 46.

In addition, when two types of pointing tools 4 for proximity and remote use are used as described above, two or more operators simultaneously operate, or a plurality of pointing tools 4 having different attributes such as colors and thicknesses are used. For this reason, the light emission control unit 42 is set to transmit a unique ID number together with a control signal. In accordance with the transmitted ID number, attributes such as the thickness and color of the drawn line are determined by software on the external connection device side, and the setting can be changed by a button or menu on the screen 10. Can be. For this operation, an operation button or the like may be separately provided on the indicating tool 4 to transmit a change instruction signal. For these settings, the state is maintained in the indicating tool 4 or the coordinate detector 1. It is also possible to configure so that attribute information, instead of the ID number, is transmitted to the externally connected device.

Further, such additional operation buttons can be set so that other functions such as blinking of a display device, switching of a signal source, operation of a recording device, and the like can be performed.
Further, by providing pressure detection means in one or both of the switches 43A and 43B, pen pressure detection is performed, and various useful signals such as transmission of this pen pressure data together with a control signal can be transmitted. is there.

When the switch 43A or the switch 43B of the indicator 4 is turned on, light emission starts, and the light emission signal is a header consisting of a reader unit composed of a relatively long continuous pulse train, followed by a code (such as a maker ID). The information is output first in accordance with a predetermined order and format of a transmission data string including a pen ID and a control signal (see FIG. 9, LSG signal).

In the embodiment of the present invention, in each data bit, a "1" bit is formed in a modulation format having an interval twice as long as a "0" bit. Various ones can be used. However, as will be described later, it is desirable that the average amount of light is constant for coordinate detection, and that the clock component is sufficiently large for tuning the PLL. Considering that there is no problem even if is relatively high, in the present embodiment, 6 bits (64 bits) are used.
Is encoded by a method of allocating to 108 codes having the same number of 1s and 0s and a continuous number of 1s or 0s of 3 or less among 10-bit length codes. By employing such an encoding method, the average power becomes constant and a sufficient clock component is included, so that a stable synchronization signal can be easily generated at the time of demodulation.

As described above, the pen down and pen button control signals are 2 bits, but other long data such as an ID must also be transmitted. Therefore,
In this embodiment, the first two bits are a control signal, the next two bits are a content identification code (for example, the pen pressure signal is 00, the ID is 11, etc.), and the next two bits are these bits. Parity, and subsequently, 16-bit data and 2-bit parity are arranged to form one block of data. When such data is encoded by the method described above, a signal having a length of 40 bits is obtained.
A 10-bit sync code is added to the head of the code. This sync code is distinguished from a data word by using a special code of 4 0s, 5 consecutive 1s, or an inverted pattern thereof (switching depending on whether the end of the previous block is 1 or 0). It is easy to identify the position even in the middle of the data string and restore the data. Therefore, one block becomes a transmission signal having a length of 50 bits, which means that the control signal and data such as a 16-bit ID or writing pressure are transmitted.

In this embodiment, the first frequency is 60 kHz.
The second frequency is 7.5 kHz, which is 1/8 of the above.
Since the above-described coding method is employed, the average transmission bit rate is 2/3 of 5 kHz. Furthermore, since one block is 50 bits, 100 Hz is 1 bit.
This means that 24-bit data is transmitted in the block. Therefore, the effective bit rate excluding parity is 2
000 bits / sec. Although the redundancy is high,
This method can prevent erroneous detection and facilitate synchronization with a very simple configuration. In addition, by using a phase synchronization signal for sensor control described later and a check for a repetition period of a sync code, even if a short dropout occurs in the signal, the signal can be followed. The discrimination from the case where a quick operation such as double tap is performed can be surely performed by the presence or absence of the header signal. <Detailed Description of Cap Made of Translucent Member Covering Light-Emitting Element> FIG. 4 is a diagram showing a detailed configuration of the cap of the present embodiment.

In the pointing tool 4, as shown in FIG.
The light-emitting element 41 is covered with a cap 46 made of a translucent member. FIG. 1 shows a configuration in which the cap 46 is a part of the operation switch 43B. However, if the configuration is such that the cap 46 covers the light emitting element 41, it is not always necessary to configure a switch. The basic configuration of the cap 46 with the portion omitted is shown (the pen down function in this case may be provided to a switch provided in another portion of the pointing tool 4).

The cap 46 is a member that comes into contact with the screen 10 when the coordinates of the tip of the pointing tool 4 are directly input in the mode of touching the screen 10. With this configuration, the light emitting element 41 such as an LED directly contacts the screen. No contact with 10. Further, since the light-emitting element 41 is spatially separated from the light-emitting element 41, no external force is exerted on the light-emitting element 41 by directly pressing the light-emitting element 41 on the screen 10. Therefore, the light emitting element 41 is not worn or scratched by friction with the screen 10 and does not affect the light emitting state.

The cap 46 is required to have a light-transmitting property for transmitting light in order to project the light from the light emitting element 41 onto the screen 10 with little attenuation.
Transparent resin materials such as A (methacrylic resin), AS (styrene and acrylonitrile copolymer), PS (polystyrene), PC (polycarbonate), and epoxy resin are used. Of course, other materials may be used as long as the material has the light-transmitting property, or they may be colored. The cap 46 is
As shown in FIG. 4, a substantially hemispherical dome having a constant thickness is mounted so as to be present in a range in contact with the screen 10 and can cope with inputting coordinates by tilting the indicator 4 as shown in FIG. It has a shape. Although not shown in FIG. 4, when a filter member is attached to the light emitting element 41, a cap 46 is further formed so as to cover the filter member.

As described above, the pointing tool 4 shown in FIG. 4 has a structure in which a space is provided between the light emitting element 41 and the cap 46 that covers the light emitting element 41. 41 is not added. Further, the cap 46 is configured to be detachable from the holder portion 47 of the pointing tool 4.

In the portion shown in FIG. 4A, the projection of the cap 46 and the dent of the holder 47 are fitted and fitted substantially, so that the cap 46 is stably fixed even when inputting by directly pressing the screen 10. You. On the other hand, the cap 46 can be removed from the main body 47 of the pointing tool 4 by pulling it out in the direction of the arrow in FIG. This pointing device 4
With the configuration described above, if the cap 46 becomes inconvenient for coordinate detection due to damage or the like, it can be easily replaced with a new cap 46. As described above, by exchanging the cap 46 without any inconvenience such as a scratch on the light emitting element 41, it is possible to always perform high-precision coordinate detection in a good state, and to extend the life of the present apparatus. The mechanism for attaching and detaching the cap 46 is shown in FIG. 4 as a simple structure to be attached to the main body 47. However, if the mechanism has good stability at the time of inputting coordinates and good operability at the time of replacement, the light-emitting element 41 may be provided with a transparent cushioning material. Needless to say, a configuration in which the sensor is mounted and attached via an intermediary or the like, or another configuration may be used.

FIG. 5 is a diagram showing another detailed configuration of the cap according to the present embodiment.

FIG. 5 shows an embodiment in which the detachable light-transmitting cap has lens characteristics. The cap 461 has an optically concave lens characteristic, and the cap 462 has an optically convex lens characteristic.
As mentioned above, in the case of direct input, a diffuse light source is sufficient,
An inexpensive LED is sufficient as a light emitting element.
In itself, the transparent encapsulating resin is provided with a condenser lens characteristic.
In this case, the diffusion is insufficient, and the indicator 4
Is input to the screen 10 which is the coordinate input surface while lying down, there is a case where the light amount is insufficient for the coordinate detector 1.

Therefore, in the case of direct input, by mounting the cap 461 having the concave lens characteristic,
Even when the pointing tool 4 is used at a wider angle with respect to the screen 10, a sufficient amount of light can be obtained, and operability is improved. On the other hand, when used as a pointer, by attaching and using a cap 462 having a convex lens characteristic, even if a light beam is emitted from a place further away from the screen 10, a light spot 5 with a sufficient light amount is generated. be able to.

The concave lens portion of the cap 461 should be designed optimally in consideration of the input angle used by the indicator 4 and the light quantity, the restrictions on the arrangement such as the distance from the light emitting element 41, and the directivity of the light emitting element 41. Is desirable. The same applies to the convex lens portion of the cap 462, and it is preferable to design an optimal optical design so as to be a parallel light beam in consideration of the distance from the screen 10, the light amount, the characteristics of the light emitting element, and the like.

FIG. 6 is a diagram showing another detailed configuration of the cap according to the present embodiment.

FIG. 6 shows an embodiment in which the cap shown in FIG. 5 is integrated with the cap for further convenience. Reference numeral 463 denotes a cap having an optically concave lens characteristic, and reference numeral 464 denotes a cap formed of a lens portion having an optically convex lens characteristic and a cylindrical member attached to the holder 47 of the pointer 4. Direct screen 10
In case of inputting by touching, the cap 464 is removed and the cap 463 is mounted.

Accordingly, the concave lens characteristics of the cap 463 are the same as those of the cap 461. On the other hand, when it is used as a pointer, the cap 463 is mounted and the cap 464 is mounted so as to cover it. Regarding the convex lens of the cap 464, an optical design such as reducing the curvature is performed so that the parallel rays are sufficiently formed even through the concave lens of the cap 463. Also,
Since the cap 464 does not come into direct contact with the screen 10, it is not necessary to adopt a tip shape in consideration of the contact as shown in FIG. 6, and the peripheral cylindrical members other than the light projection unit are translucent members. No need.

With this configuration, the attachment / detachment of the pen cap in the input mode may be performed only for the cap 464, and the complexity is further reduced. Also, if it becomes inconvenient for coordinate detection due to damage due to use of direct input, etc.,
It goes without saying that the cap 463 can be easily replaced with a new one. Although not particularly shown in the drawings, in the case of the cap shown in FIGS. 5 and 6, in order to adjust the state of the spot 5 generated on the screen 10 and the amount of light detected by the coordinate detector 1, A configuration that can move the position back and forth may be provided. Further, a plurality of lenses may be configured by performing aberration design.

Further, a cap 465 provided with a simple zoom lens mechanism as shown in FIG. 7 may be used to reduce the complexity of attaching and detaching the pen cap in the input mode.
In the change of the relative positions of the zoom lens groups, it is not necessary to keep a balance over a wide range, and it is sufficient to design the optical system only at least for the telephoto for the pointer and the wide arrangement for the direct input. FIG. 7 shows four zoom lens groups. However, two zoom lens groups can be configured, and another configuration may be used.

According to this configuration, the position of the lens is zoom-adjusted without the trouble of attaching and detaching the cap every time the input mode is switched, so that the pointing tool 4 can optimize the screen 10 as the coordinate input surface according to the input mode. Light spot can be formed. Of course, when the relationship between the zoom lens groups is changed, if the design is such that the balance is achieved over a wide range, an optimal light spot can be formed according to the distance from the screen 10 in the pointer mode. Further, in the case where it becomes inconvenient for coordinate detection due to damage due to use of direct input or the like, the entire cap 465 or only the tip portion can be replaced. <Detailed Description of Coordinate Detector 1> FIG. 8 is a diagram showing a detailed configuration of the coordinate detector of the present embodiment.

The coordinate detector 1 includes a light receiving element 6 for detecting the amount of light with high sensitivity by a condensing optical system, and two linear sensors 20 for detecting the direction of arrival of light by an imaging optical system.
X and 20Y are provided. Then, the light beam from the light emitting element 41 incorporated in the pointing device 4 receives the diffused light from the light spot 5 generated on the screen 10. <Explanation of Operation of Light-Condensing Optical System> The light-receiving element 6 is provided with a light-collecting lens 6a as a light-condensing optical system, and detects a light amount of a predetermined wavelength with high sensitivity from the entire range on the screen 10. This detection output is detected by the frequency detection unit 71, and then demodulated by the control signal detection unit 72 into a digital signal including data such as a control signal (a signal superimposed by the light emission control unit 42 of the indicator 4).

A timing chart in the control signal restoring operation will be described with reference to FIG.

FIG. 9 is a timing chart in the control signal restoring operation of the present embodiment.

The data signal composed of the bit string as described above is detected by the light receiving element 6 as a light output signal LSG.
The frequency is detected by the frequency detector 71. The frequency detection unit 71
The optical output signal LSG is configured to be tuned to the pulse period of the highest first frequency in the optical output signal LSG. When used in combination with an optical filter, it is not affected by disturbance light.
The modulation signal CMD is demodulated. This detection method is similar to a widely used infrared remote controller, and is a highly reliable wireless communication method.

In this embodiment, the first frequency is set to 60 kHz which is higher than that of a generally used infrared remote controller, and the first frequency is configured so as not to malfunction even when used at the same time. The first frequency can be set to the same band as a generally used infrared remote controller. In such a case, malfunction is prevented by identifying the first frequency with an ID or the like.

The modulated signal CMD detected by the frequency detector 71 is interpreted as digital data by the control signal detector 72, and the above-described control signals such as pen-down and pen-button are restored. The restored control signal is sent to the communication control unit 33. The modulation signal C
The code modulation cycle, which is the second frequency included in the MD, is detected by the sensor control unit 31, and this signal controls the linear sensors 20X and 20Y. That is, the sensor control unit 31 resets at the timing of the header shown in FIG.
A signal LCK synchronized with the falling edge of MD is generated.

Therefore, the generated signal LCK is a signal of a constant frequency synchronized with the presence / absence of light emission of the indicator 4. Further, from the modulation signal CMD, a signal LON indicating presence / absence of light input and a sensor reset signal RCL activated by the signal LON are generated. While the sensor reset signal RCL is at the high level, the two linear sensors 20X and 20Y are reset, and a synchronous integration operation described later is started at the falling timing of the sensor reset signal RCL synchronized with the rising of the signal LCK.

On the other hand, the control signal detecting section 72 detects the header section and confirms that the input from the pointing device 4 has been started, not other equipment or noise, and a signal indicating this confirmation is transmitted to the communication control section 33. Is transmitted to the sensor control unit 31, the signal CON indicating the validity of the operation of the linear sensors 20X and 20Y is set to a high level, and the operation of the coordinate calculation unit 32 is started.

FIG. 10 shows that the light output signal LSG is lost,
4 shows a timing chart at the end of a series of operations.
When the modulation signal CMD detected from the optical output signal LSG keeps the low level for a certain period of time or more, the signal LON indicating the presence or absence of the optical input goes low, and the signal CON indicating the validity of the sensor operation also goes low. As a result, the output operation of the coordinates by the linear sensors 20X and 20Y ends. <Explanation of Operation of Imaging Optical System> FIG. 11 is a diagram showing an arrangement relationship between the linear sensors 20X and 20Y of the present embodiment.

In FIG. 11, the image of the light spot 5 is linearly formed on the photosensitive portions 21X and 21Y of the linear sensors 20X and 20Y by the cylindrical lenses 90X and 90Y as the image forming optical system. By arranging these linear sensors 20X and 20Y exactly at right angles, each of them has an X coordinate,
An output having a peak at a pixel reflecting the Y coordinate is obtained.

The two linear sensors 20
X and 20Y are controlled by a sensor control unit 31, and output signals are output from an AD conversion unit 31 connected to the sensor control unit 31.
A sends it to the coordinate calculation unit 32 as a digital signal. The coordinate calculation unit 32 calculates an output coordinate value from the input digital signal, and outputs the calculation result to the control signal detection unit 72.
The data is transmitted to an external control device (not shown) by a predetermined communication method through the communication control unit 33 together with data such as a control signal from the control unit. When performing an unusual operation (for example, setting a user calibration value) such as at the time of adjustment, the communication control unit 33
Sends a mode switching signal to the sensor control unit 31 and the coordinate calculation unit 32.

In the present invention, the focus is adjusted so that the image of the light spot 5 has an image width several times as large as the pixels of the linear sensors 20X and 20Y, and blur is intentionally caused. 1.5mm diameter plastic cylindrical lens, pixel pitch about 15μm, effective 64 pixels linear CCD, infrared LE
According to the experiment using D, when the sharpest image is formed, the image width becomes 15 μm or less over the entire angle of view of about 40 degrees. In such a state, it has been found that the result of the inter-pixel division calculation is distorted stepwise. Therefore, if the image width is 3
When the position of the lens was adjusted to be about 0 to 60 μm, very smooth coordinate data was obtained. Of course, if the image is largely blurred, the peak level will be reduced. Therefore, an image width of about several pixels is optimal. Using a CCD with a small number of pixels and a moderately blurred optical system
It is one of the points of the present invention. By using such a combination, a coordinate input device with a small amount of calculation data, a very high resolution, a high accuracy, a high speed and a low cost can be realized with a small sensor and an optical system. it can.

The X-coordinate detecting linear sensor 20X and the Y-coordinate detecting linear sensor 20Y arranged in an array have the same configuration, and the detailed configuration will be described with reference to FIG.

FIG. 12 is a diagram showing a detailed configuration of the linear sensor of this embodiment.

The sensor array 21 serving as a light receiving section is composed of N pixels (64 pixels in the present embodiment), and charges corresponding to the amount of received light are stored in the integrating section 22. The integrator 22 calculates N
It can be reset by applying a voltage to the gate ICG, so that an electronic shutter operation is possible.
The electric charge stored in the integration unit 22 is transferred to the storage unit 23 by applying a pulse voltage to the electrode ST. The storage section 23 is composed of 2N pieces, and charges are separately stored corresponding to H (high level) and L (low level) of the IRCLK signal synchronized with the light emission timing of the indicator 4. Thereafter, the charges separately accumulated in synchronization with the blinking of the light are transferred to the 2N linear CCD units 25 via the 2N shift units 24 provided for simplifying the transfer clock. Is done.

Thus, the linear CCD section 25 has N
The electric charges corresponding to the blinking of the light output from the sensor output of the pixel are stored adjacent to each other. These linear CCDs
The charges arranged in the part 25 are 2N ring CCs.
The data is sequentially transferred to the D unit 26. This ring CCD 26
After being emptied by the CLR unit 27 by the CLR signal, the charges from the linear CCD unit 25 are sequentially accumulated.

The charges thus accumulated are read out by the amplifier 29. The amplifier 29 is non-destructive and outputs a voltage proportional to the amount of accumulated charge. Actually, the difference between the adjacent charge amounts, that is, the light emitting element 4
A value obtained by subtracting the charge amount at the time of non-lighting from the charge amount at the time of lighting 1 is amplified and output.

At this time, the obtained linear sensors 20X, 2
An example of the output waveform of 0Y will be described with reference to FIG.

FIG. 13 is a diagram showing an example of the output waveform of the linear sensor according to the present embodiment.

In FIG. 13, the waveform B is a waveform when only the signal when the light emitting element 41 is turned on is read out, and the waveform A is a waveform when the light emitting element 41 is not turned on, that is, only the disturbance light. As shown in FIG. 12, charges of pixels corresponding to the waveforms of A and B are arranged adjacent to each other on the ring CCD 26). The amplifier 29 non-destructively amplifies and outputs the difference value (the waveform of B-A) between the adjacent charge amounts. As a result, it is possible to obtain a signal of only the light from the indicator 4. It is possible to input coordinates stably without being affected by disturbance light (noise).

If the maximum value of the waveform B-A shown in FIG. 13 is defined as the PEAK value, if the accumulation time during which each of the linear sensors 20X and 20Y functions for light is increased, The PEAK value increases with the time. In other words, if the time corresponding to one cycle of the IRCLK signal is defined as a unit accumulation time and the number of accumulations n is defined using the unit as the unit, the PEAK value increases by increasing the number of accumulations n. Then, by detecting that the PEAK value has reached the predetermined magnitude TH1, it is possible to always obtain an output waveform of a constant quality.

On the other hand, when the disturbance light is very strong, the ring CC is required before the peak of the differential waveform BA becomes sufficiently large.
The transfer charge of D26 may be saturated. In consideration of such a case, each linear sensor of the linear sensors 20X and 20Y is provided with an SKIM unit 28 having a skim function. The SKIM unit 28 monitors the level of the non-lighting signal. In FIG. 14, when the signal level exceeds a predetermined value at the n-th An (in FIG. 14, a dashed line in FIG. 14), a certain amount of electric charges A, B From each pixel.
As a result, in the next (n + 1) -th time, a waveform as shown in An + 1 is obtained, and by repeating this, even if there is extremely strong disturbance light, signal charges can be accumulated without being saturated.

Therefore, even if the light quantity of the blinking light from the pointing device 4 is weak, by continuing the integration operation many times, it is possible to obtain a sufficiently large signal waveform.
In particular, when a light source in the visible light range is used for the indicator 4, the display image signal is superimposed. Therefore, by using the above-described skim function and difference output, it is possible to obtain a sharp waveform with very little noise. Becomes

Next, operation control of the linear sensors 20X and 20Y will be described with reference to FIG.

FIG. 15 is a flowchart showing the operation control of the linear sensor of this embodiment. When the sensor control section 31 starts the sensor control operation, the signal CON is monitored in step S102. If the signal CON is at the high level (YES in step S102), the process proceeds to step S103, and the number of accumulations n is reset to zero.
Then, in step S104, the PE of the sensor output is output.
It is determined whether the AK value (peak level) is greater than a predetermined value TH1.

If the PEAK value is less than the predetermined value TH1 (NO in step S104), it is determined in step S105 whether the number of accumulations n is greater than a first predetermined number n0. If the number of accumulations n is less than the first predetermined number of times n0 (NO in step S105), the process proceeds to step S106, where the number of accumulations n is incremented by one, and step S1 is performed.
Return to 04. On the other hand, when the PEAK value is larger than the predetermined value TH1 (YES in step S104), or when the accumulation number n is larger than the first predetermined number n0 (step S1).
(05, YES), the process proceeds to step S107, where the integration stop signal RON becomes high level (H), and the integration operation is stopped. Then, the coordinate value calculation process by the coordinate calculation unit 32 is started.

Thereafter, in step S108, it is determined whether the number of accumulations n is greater than a second predetermined number n1. When the number of accumulations n is less than the first predetermined number of times n1 (NO in step S108), the process proceeds to step S109, the number of accumulations n is incremented by 1, and the process returns to step S108. On the other hand, if the accumulation number n is larger than the first predetermined number n1 (YES in step S105), step S110
, The integration stop signal RON goes low, and at the same time, the sensor reset signal RCL goes high for several times (two times in FIG. 10) the period of the signal LCK. Next, in step S112, the signal CON is monitored. When the signal CON is at a high level (Y in step S112)
ES), and proceed to step S103. On the other hand, if the signal CON is at the low level (NO in step S112), the process proceeds to step S111 and waits for one processing cycle.

That is, while the signal CON is at the high level, this operation is repeated, and the coordinate value calculation is performed at intervals determined by the predetermined number n1. Also, under the influence of garbage,
Step S111 is provided so that the state is maintained only once even if the signal CON drops. if,
If the signal CON is at the low level for two consecutive periods (NO in step S102), the process proceeds to step S113, where the flag pon is reset to 0, a state waiting for a sync signal is returned, and the state returns to the initial state.

The drop-out countermeasure portion can be longer than one cycle, and it goes without saying that it can be shortened if the disturbance is small. Note that the same operation can be performed by setting one cycle here as a natural number multiple of the above-described data block cycle and matching the sync code timing, and using a sync code detection signal instead of the signal CON.

The light of the indicator 4 reaching the coordinate detector varies due to the consumption of the power supply (battery) 44 built in the indicator 4 and also varies depending on the attitude of the indicator 4. In particular, when the light diffusing property of the screen 10 is small, the front luminance of the displayed image is improved, but the fluctuation of the amount of light input to the sensor due to the posture of the pointing tool 4 is increased. However, in the present invention, even in such a case, since the number of integrations automatically follows and an output signal that is always stable can be obtained, an excellent effect of enabling stable coordinate detection can be obtained. . Further, when light is incident on the sensor without being scattered as much as a pointer, considerably intense light enters, but it is clear that even in such a case, stable coordinate detection can be performed.

Further, the LE used by directly touching the screen is used.
When a pen using D and a pointer are used together, LEDs having a larger light amount can be used.
The first predetermined number of times n0 and the second predetermined number of times n1, which are the number of integrations shown in FIG. 5, are discriminated as a pen or a pointer based on the ID signal, and switching is performed. It is also possible. Actually, it is impossible to draw a delicate drawing operation like a character input with a pointer. Rather, it is more convenient to draw a smooth line by low-speed sampling, and it is effective to provide such switching.

As described above, a high-frequency carrier is added to the blinking light, and the timing of the integration operation is controlled by a demodulated signal having a predetermined period obtained by frequency-detecting the carrier. The image unit and the image unit can be synchronized cordlessly, and an easy-to-use coordinate input device can be realized. Further, by using a laser beam, there is obtained an excellent advantage that it is possible to easily work at a position away from the screen. Further, since the integration control means for detecting that the peak level in the difference signal from the integration section exceeds a predetermined level and stopping the integration operation is provided, the signal of the light spot image having a substantially constant level even when the light amount changes. Can be created, whereby a stable and high-resolution coordinate calculation result can always be obtained. <Coordinate Value Calculation> Next, the coordinate calculation process in the coordinate calculation unit 32 will be described with reference to FIG.

FIG. 16 is a flowchart showing a coordinate calculation process in the coordinate calculation unit of this embodiment.

The output signals (difference signals from the amplifier 29) of the two linear sensors 20X and 20Y obtained as described above are converted into digital signals by an AD conversion unit 31A provided in the sensor control unit 31 as a coordinate calculation unit. 32,
Coordinate values are calculated. First, the coordinate values are calculated using the X coordinate,
For output data in each direction of the Y coordinate, coordinate values (X1, Y1) on the sensor are obtained. Note that the calculation processing is X,
Since it is the same as Y, only X will be described.

First, in step S202, difference data Dx which is a difference signal of each pixel at an arbitrary coordinate input point (a predetermined point whose coordinates are known in a reference point setting mode to be described later).
(N) (the number of pixels n = 64 in this embodiment) is read and stored in a buffer memory (not shown). Next, in step S203, a preset threshold V
And calculates a data value Ex (n) that is equal to or larger than the threshold value.
Using this data value Ex (n), a coordinate X1 on the sensor is calculated in step S204. In the present embodiment, the center of gravity of the output data is calculated by the center of gravity method.
It goes without saying that there are a plurality of calculation methods such as a method of obtaining the peak value of the data value Ex (n) (for example, by a differentiation method).

In step S205, the mode of the coordinate calculation process is determined. In order to calculate coordinates from the center of gravity X1 of the output data, it is necessary to obtain a predetermined value in advance, and a method of deriving the predetermined value (reference point setting mode) will be described.

Similarly, if only the X direction is described,
A point (α1,
In .beta.1), and ([alpha] 2, .beta.2), located a pointing device 4, respectively perform the steps S202 to S204, the centroid value of the X-direction sensor obtained at each point, calculated as X1 _1, X1 _2, the The values and the known coordinate values α1 and α2 are stored in step 210. At the time of ordinary coordinate calculation using this stored value, the X coordinate of the coordinate input point to be calculated can be calculated in step S206. In step S207, coordinate values are corrected as needed (for example, the distortion is corrected by a software operation to correct the lens aberration of the optical system) in order to provide a higher-performance coordinate input device. Etc.) to determine the coordinate values.

It is needless to say that the determined coordinates can be output as it is in real time, or data can be thinned out according to the purpose (for example, only one data is output for every ten determined coordinates). However, it is important when the following specifications are assumed.

The stability of the user's hand differs between when the pointing tool 4 is used like a pen and when it is used away from the screen as a pointer. When used as a pointer, the cursor on the screen will tremble finely, so it is easier to use such a fine movement. On the other hand, when used like a pen, it is required to follow as quickly as possible. In particular, when writing a character, if a small quick operation cannot be performed, the input cannot be performed correctly.

In this embodiment, since the ID is transmitted by the control signal, it is possible to determine whether or not the pointer is pressed, that is, whether or not the tip switch is pressed. You can determine whether you are using it. If it is a pointer, for example,
The output coordinate values (X-1, Y-1) and (X
If the current output coordinate value (X, Y) is calculated by calculating a moving average using (−2, Y-2), a configuration with less blur and good operability is obtained. In addition, although a simple moving average is used, other functions used for such a smoothing process include a non-linear compression of the absolute difference value according to the magnitude, and a prediction value based on the moving average. Various methods, such as non-linearly compressing the difference of, can be used.

In other words, when the pointer is used as a pointer, it is possible to increase the level of smoothing, otherwise, it is possible to switch the level to a lower level by the control signal. In this respect, the effect of the present invention is great. Further, in the present invention, when the dedicated caps for the pointer and the pen are replaced as described above, means for discriminating the respective caps are provided on the main body of the cap and the pen 4, whereby the pointer or the pen is used. You may determine whether you are using it.

Note that, as described above, when the coordinate sampling frequency is 100 Hz, these arithmetic
The processing may be completed within sec, and the original data is 64 pixels × 2
The (x and y) × AD conversion unit is as small as 8 bits and does not require any convergence operation, so that a low-speed 8-bit 1-chip microprocessor can perform sufficient processing. This is advantageous not only in terms of cost but also in that specifications can be easily changed, development time can be shortened, and development of various derivative products can be facilitated. In particular, there is no need to develop a dedicated LSI for performing high-speed image data processing as in the case of using an area sensor, and the advantages such as development cost and development period are very large.

The data signal indicating the coordinate value (X, Y) calculated by the above-described arithmetic processing is supplied to the coordinate arithmetic unit 32.
Is sent to the communication control unit 33 from. The data signal and the control signal from the control signal detection unit 72 are input to the communication control unit 33. The data signal and the control signal are both converted into a communication signal of a predetermined format,
It is sent to an external display control device. Thus, various operations such as input of a cursor, a menu, characters and line drawings on the screen 10 can be performed. As mentioned above, 6
Even when a 4-pixel sensor is used, a resolution of more than 1000 and sufficient accuracy can be obtained, and both the sensor and the optical system are small,
It is possible to obtain a coordinate input device that can have a low-cost configuration and can have a very small configuration of an arithmetic circuit.

When the sensor is configured as an area sensor, doubling the resolution requires four times the number of pixels and calculation data. On the other hand, when the sensor is configured as a linear sensor, Only needs to double the number of pixels in each of the X and Y coordinates. Therefore, it is easy to increase the number of pixels to achieve higher resolution.

As described above, according to the present embodiment, the indicator is provided with the detachable light-transmitting member that covers the light emitting element, so that the light emitting element itself is not affected at the time of coordinate input. , And a decrease in the amount of light emission due to wear,
When a change in the light emission distribution causes a problem with light irradiation, the translucent member can be replaced with a new member, so that light can always be emitted in a good state and a stable light emission state is maintained for a long period of time. In addition, a high-resolution and high-performance coordinate input device can be provided.

Further, the translucent member may include a plurality of exchangeable translucent members having different irradiation optical characteristics. Thereby, it is possible to provide an optimal emission function of the indicator according to the application.

The present invention can be applied to a system including a plurality of devices (for example, a host computer, an interface device, a reader, a printer, etc.), but can be applied to a single device (for example, a copying machine or a facsimile machine). Etc.).

Further, an object of the present invention is to provide a storage medium storing a program code of software for realizing the functions of the above-described embodiments to a system or an apparatus, and a computer (or CPU) of the system or apparatus.
And MPU) read and execute the program code stored in the storage medium.

In this case, the program code itself read from the storage medium realizes the functions of the above-described embodiment, and the storage medium storing the program code constitutes the present invention.

As a storage medium for supplying the program code, for example, a floppy disk, hard disk, optical disk, magneto-optical disk, CD-ROM, CD
-R, a magnetic tape, a nonvolatile memory card, a ROM, or the like can be used.

The functions of the above-described embodiments are implemented when the computer executes the readout program codes, and the OS (Operating System) running on the computer is executed based on the instructions of the program codes. ) May perform some or all of the actual processing, and the processing may realize the functions of the above-described embodiments.

Further, after the program code read from the storage medium is written into a memory provided in a function expansion board inserted into the computer or a function expansion unit connected to the computer, based on the instruction of the program code, It goes without saying that the CPU included in the function expansion board or the function expansion unit performs part or all of the actual processing, and the processing realizes the functions of the above-described embodiments.

[0104]

As described above, according to the present invention,
It is possible to provide a coordinate input pen that maintains a stable light emitting state for a long time and enables high-resolution and high-performance coordinate input.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a schematic configuration of a coordinate input device according to an embodiment.

FIG. 2 is a diagram showing a detailed configuration of a pointing device of the embodiment.

FIG. 3 is a diagram illustrating an operation mode of the pointing device according to the embodiment.

FIG. 4 is a diagram showing a detailed configuration of a cap according to the embodiment.

FIG. 5 is a diagram showing another detailed configuration of the cap according to the embodiment.

FIG. 6 is a diagram showing another detailed configuration of the cap according to the embodiment.

FIG. 7 is a diagram showing another detailed configuration of the cap according to the embodiment.

FIG. 8 is a diagram illustrating a detailed configuration of a coordinate detector according to the present embodiment.

FIG. 9 is a timing chart in a control signal restoring operation of the embodiment.

FIG. 10 is a diagram showing an example of an output waveform for explaining a skim operation of the linear sensor according to the embodiment.

FIG. 11 is a diagram showing an arrangement relationship between the linear sensors 20X and 20Y of the present embodiment.

FIG. 12 is a diagram illustrating a detailed configuration of a linear sensor according to the present embodiment.

FIG. 13 is a diagram illustrating an example of an output waveform of the linear sensor according to the embodiment.

FIG. 14 is a diagram schematically showing an output of a linear sensor.

FIG. 15 is a flowchart illustrating operation control of the linear sensor according to the present embodiment.

FIG. 16 is a flowchart illustrating a coordinate calculation process in a coordinate calculation unit according to the present embodiment.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 coordinate detector 2 coordinate detection sensor unit 3 controller 4 indicator 5 light spot 6 light receiving element 6 a condenser lens 7 signal processing unit 8 projection display device 81 image signal processing unit 82 liquid crystal panel 83 lamp 84 mirror 85 condenser lens 86 projection Lens 20X, 20Y Linear sensor 21 Sensor array 22 Integrator 23 Shift unit 24 Storage unit 25 Linear CCD 26 Ring CCD 27 Clear unit 28 Skim unit 29 Amplifier 31 Sensor control unit 31A AD conversion unit 32 Coordinate calculation unit 33 Communication control unit

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Katsuyuki Kobayashi, Inventor 3-30-2 Shimomaruko, Ota-ku, Tokyo Within Canon Inc. (72) Inventor Jun Tanaka 3-30-2, Shimomaruko, Ota-ku, Tokyo Canon Inside the Company (72) Inventor Isao Kobayashi Within Canon Inc. 3- 30-2 Shimomaruko, Ota-ku, Tokyo Inside (72) Inventor Masaaki Kinpu Inside 30-3-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. F term (reference) 5B068 AA01 AA11 BC03 BD02 BD04 BD09 BD20 BD21 CC17 CC18 5B087 AA04 AB02 AE03 BC03 BC11 BC17 BC19 BC22 BC32 CC09 CC26 CC33

Claims (8)

[Claims] 1. A coordinate input pen that irradiates a predetermined position on a coordinate input screen with light to generate a light spot and inputs coordinates corresponding to the light spot, wherein: a light emitting unit that emits light; And a translucent member that covers the means and is detachable from the coordinate input pen. 2. The light-transmitting member is made of a transparent resin material containing at least one of PMMA (methacrylic resin), AS (styrene, acrylonitrile copolymer), PS (polystyrene), PC (polycarbonate), and epoxy resin. The coordinate input pen according to claim 1, wherein the pen is configured. 3. The light-transmitting member has a substantially hemispherical dome shape having a constant thickness.
The coordinate input pen described in. 4. The coordinate input pen according to claim 1, wherein the translucent member is a translucent member having a concave lens that diffuses to the coordinate input screen. 5. The coordinate input pen according to claim 1, wherein the translucent member is a translucent member having a convex lens characteristic for converging light on the coordinate input screen. 6. The light-transmitting member has a first light-transmitting member having a concave lens that diffuses to the coordinate input screen, and a second light-transmitting member having a convex lens characteristic for condensing light on the coordinate input screen. Wherein the first light-transmitting member has a substantially hemispherical dome shape, the second light-transmitting member has a cylindrical shape, and the first light-transmitting member is attached to the light-emitting means. The coordinate input pen according to claim 1, wherein the second light-transmitting member is mounted on the light-transmitting member. 7. The light-transmitting member has a first light-transmitting member having at least a concave lens that diffuses to the coordinate input screen, and a second light-transmitting member having a convex lens characteristic for condensing light on the coordinate input screen. The coordinate input pen according to claim 1, further comprising a member, wherein the first light-transmitting member and the second light-transmitting member constitute a zoom lens mechanism. 8. The coordinate input pen according to claim 1, wherein the translucent member is constituted by a plurality of exchangeable translucent members having different irradiation optical characteristics.