JP2000181627A - Indicating tool for coordinate input and coordinate input device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce friction accompanying movement on a screen where an indication is made, to suppress the influence of disturbing light, and to input high-resolution, high-performance coordinate information by equipping the indicating tool with a spherical lens atop rotatably on the optical path of light emitted by a light emitting element. SOLUTION: The indicating tool 4 internally has the light emitting element 41, such as a semiconductor laser or LED, which emits a light beam, a light emission control means 42 which drives and controls its light emission, plural switch means 43 for operation which are equipped with switches 43A to 43D, and a power source means 44 such as a battery. The light emission control means 42 turns ON and OFF the light emission according to the states of the switches 43 for operation and performs light emission control while a control signal is superposed. On the tip part of the indicating tool 4, the rotatable transparent spherical lens 11 is mounted so as to prevent the indicating tool 4 and screen 10 from being rubbed frictionally against each other when characters, etc., are written by pressing the indicating tool 4 against the screen 10 and also to form a light spot 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coordinate input indicator for inputting a coordinate position by irradiating light emitted from a light emitting element onto a coordinate input screen, and to detect light emitted from the indicator. A coordinate input device for determining a coordinate input position.

[0002]

2. Description of the Related Art As a conventional coordinate input device, a light spot on a screen is imaged using a CCD area sensor or a linear sensor, and image processing such as using barycentric coordinates or pattern matching is performed to calculate coordinate values. And a device using a position detecting element called PSD (an analog device that can obtain an output voltage corresponding to the position of the spot) are known.

[0003] For example, Japanese Patent Publication No. 7-76902 discloses an apparatus for detecting a coordinate by imaging a light spot with a parallel beam of visible light with a video camera and simultaneously transmitting and receiving a control signal with infrared diffused light. ing. Japanese Patent Application Laid-Open No. 6-274266 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 recent years, the brightness of the screen of a large-screen display has been improved, and it has become possible to use it even in a brightly illuminated environment, and the demand is expanding. The coordinate input device is increasingly required to be resistant to disturbance light so that it can be used in an environment combined with such a large-screen display.

In recent years, devices using infrared rays have been increasing as wireless communication means. Since disturbance light has been increasing in both infrared and visible light, it is important for a device to be strong against disturbance light. One of the characteristics.

However, the aforementioned Japanese Patent Publication No. 7-76902
As can be seen from JP-A-6-274266 and JP-A-6-274266, in a device using a conventional CCD sensor, disturbance light can be suppressed only by an optical filter.

On the other hand, Japanese Patent No.
As shown in the figure, in the device using the PSD, the light intensity is frequency-modulated and the modulated wave is synchronously detected, so that the influence of the disturbance light can be suppressed. Has strong characteristics.

[0009] In addition, the resolution of the large-screen display has been increased as well as the brightness. For this reason, it is necessary to improve the resolution of the coordinate input device, but there is a problem in this respect in a device using a PSD that is strong against disturbance light.

That is, since the dynamic range of the sensor output voltage directly corresponds to the input range, for example, when the whole is decomposed into 1000 coordinates, at least 6
Since an S / N ratio of 0 dB or more is required, and digital correction of linearity error is indispensable, as described in the above-mentioned Patent No. 2503182, a high-precision analog circuit and a multi-bit AD converter are required. And an arithmetic circuit are required.

Further, since the S / N ratio of the sensor output signal depends on the amount of light and the sharpness of the light spot, suppression of disturbance light alone is not sufficient, and a bright and highly accurate optical system is also required. For this reason, the device itself is very expensive and large.

Further, as a technique for increasing the resolution by using a CCD sensor, Japanese Patent Publication No. 7-76902 discloses that a plurality of video cameras are used at the same time. become. Also,
In the case of a single video camera having a large number of pixels, the size and cost are further increased as compared with the case of using a plurality of cameras.

Further, in order to achieve a resolution higher than the number of pixels by image processing, high-speed processing of enormous image data is required, and it is very large and expensive for real-time operation. .

In Japanese Patent Application Laid-Open No. Hei 6-274266, a high resolution is obtained by a special optical mask and signal processing.
If the N ratio can be secured, high resolution can be achieved.

However, in actuality, the linear sensor forms an image in a linear manner and cannot separate the light from disturbance light in a plane as compared with an area sensor that forms a point image. There is a problem that it is practical only in a special environment with little light.

The present invention has been made in order to solve the above-mentioned problems, and the present invention uses a rotatable spherical lens at the tip, which is a light-emitting portion of a pointing tool, to move on a screen for pointing. By providing a small-sized, low-cost pointing device and a coordinate input device for inputting high-resolution and high-performance coordinate information, which can reduce friction due to and reduce the influence of disturbance light and can input high-performance coordinate information. is there.

[0017]

According to a first aspect of the present invention, a light emitted from a light emitting element (light emitting element 41 shown in FIG. 2) is irradiated on a coordinate input screen (screen 10 shown in FIG. 2). A pointing device (a pointing device 4 shown in FIG. 2) for inputting a coordinate position, wherein the pointing device is provided on the optical path of light emitted from the light emitting element and at the tip of the pointing device. And a rotatable spherical lens (lens 11 shown in FIG. 2) for forming spot light.

According to a second aspect of the present invention, the rotatable spherical lens is provided at an isolated position without directly contacting the light emitting element.

According to a third aspect of the present invention, a plurality of switches (switches 43A, 43B, 43C, 43D shown in FIG. 2) for inputting a plurality of different pieces of information are provided at predetermined positions.

According to a fourth aspect of the present invention, there is provided a coordinate input device for detecting a spot light emitted from an indicator passing through a coordinate input screen (the screen 10 shown in FIG. 2) to determine coordinate input information, Detecting means (linear sensor 20 shown in FIG. 4) for detecting a spot light indicating the coordinate input screen
X, 20Y) and arithmetic means (Sensor control means 31, AD conversion means 3 shown in FIG. 4) for performing predetermined arithmetic processing on the position information detected by the detection means to calculate the coordinate position.
1A, coordinate calculation means 32), and a control means (communication control means 33 shown in FIG. 4) for reflecting the coordinate position calculated by the calculation means in an instruction on the coordinate input screen.

[0021]

FIG. 1 is a schematic view for explaining the configuration of a coordinate input device according to an embodiment of the present invention. Broadly, a light spot is formed on a screen 10 which is a coordinate input surface. Pointer 4 and screen 1 of light spot 5
And a coordinate detector 1 for detecting the position coordinates on 0.
As an output device, a projection display device 8 that displays an image or the above-described position information on a screen 10 is described.

Referring to FIG. 1, a coordinate detector 1 includes a coordinate detection sensor unit 2, a controller 3 for controlling the sensor unit and calculating coordinates, a control signal detection sensor 6, and a signal processing unit 7. The coordinate position of the light spot 5 of the indicator 4 on the screen 10 and a control signal corresponding to the state of each switch of the indicator 4 to be described later are detected, and the controller 3 sends the information to an external connection device (not shown). To communicate.

The projection type display device 8 includes an image signal processing unit 81 to which an image signal from a display signal source which is an external connection device such as a computer (not shown) is input, a liquid crystal panel 82 controlled by the image signal processing unit 81, An illumination optical system including a lamp 83, a mirror 84, and a condenser lens 85, and a projection lens 86 for projecting an image of the liquid crystal panel 82 onto the screen 10.
The desired image information can be displayed on the screen 10. 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 is incident on the coordinate detector 1 irrespective of the direction of the light beam.

FIG. 2 is a cross-sectional configuration diagram for explaining details of the pointing tool 4 shown in FIG. 1, and the same components as those in FIG. 1 are denoted by the same reference numerals.

In the figure, a pointing tool 4 includes a semiconductor laser for emitting a light beam or a light emitting element 41 such as an LED,
It incorporates a light emission control means 42 for driving and controlling the light emission, a plurality of operation switch means 43 including switches 43A to 43D described later, and a power supply means 44 such as a battery. The light emission control means 42 performs light emission control in which a control signal is superimposed by ON (ON) / OFF (OFF) of light emission and a modulation method described later according to the state of the operation switch 43.
When writing the characters by pressing the indicator 4 against the screen 10 at the tip of the indicator 4, the indicator 4 and the screen 1 are used.
0 is a rotatable transparent spherical lens 11 so as not to be rubbed by friction and for the purpose of forming the light spot 5.
Is installed.

With such a configuration, character information and line drawing information are inputted on the screen 10 by the pointing tool 4 and the information is displayed on the projection display device 8, so that it is as if a "paper and pencil". In addition to enabling input / output of information in a relationship, input operations such as button operations and icon selection decisions can be freely performed.

FIG. 3 is a diagram showing an operation mode of the pointing tool 4 shown in FIG. 2, and the switches A to D correspond to the switches 43A to 43D in FIG.

In the figure, "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 this switch is pressed, the light beam 45 is emitted. Thereby, a light spot 5 (see FIG. 1) is generated on the screen 10, and
The coordinate signal starts to be output by a predetermined process. In this state, the pen down and pen button control signals are “OF”.
F ". For this reason, on the screen 10,
Only the indication of the designated position 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 index finger and the middle finger naturally touch, the control signals of "pen down" and "pen button" are superimposed on the light emission signal as shown in FIG. Signal.
That is, by pressing the switch 43C, the state becomes “pen down”, and input of characters and line drawings is started,
Screen control such as selecting and deciding a button can be executed.

Similarly, when the switch 43D is pressed, the state becomes a "pen button", and it is possible to correspond to another function such as calling a menu. Thus, the operator can operate lightly and quickly by drawing a character or a figure or selecting a button or a menu at an arbitrary position on the screen 10 with one hand.

The switch 43A has a role of an on button. Of course switch 43A without pressing on the screen
By pressing, only the cursor on the screen 10 can be moved. Actually, the operability and accuracy are better when directly touching the screen than when inputting characters and figures away from the screen.

In the present embodiment, natural and comfortable operation can be performed even when the user is away from the screen or immediately before using the four switches, and can be used properly depending on the case. It is configured. Moreover,
If it is only for direct input (not used as a pointer), it is possible to use a diffused light source instead of a light beam, and it is possible to use an LED which is cheaper and longer in life than a semiconductor laser.

Further, when two kinds of pointing tools 4 for proximity and remote use are used as described above, two or more people operate simultaneously, or a plurality of pointing tools 4 having different attributes such as color and thickness are used. Therefore, the light emission control means 42 is set to transmit a unique ID number together with a control signal.

Then, corresponding to the transmitted ID number,
Attributes such as the thickness and color of the line to be drawn are determined by software or the like on the externally connected device, and the settings can be changed using buttons or menus on the screen 10. For this operation, an operation button or the like may be separately provided on the indicating tool 4 to transmit a change instruction signal, and these settings may be 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 a pressure detecting means in one or both of the switches 43A and 43B, pen pressure detection is performed, and various useful signals such as transmitting this pen pressure data together with a control signal can be transmitted. is there.

When the switch 43A or the switch 43B of the pointing device 4 is turned "ON", light emission is started, and the light emission signal is composed of a reader unit composed of a relatively long continuous pulse train and a code (such as a manufacturer ID) following the reader unit. Is output first, and then the information is sequentially output according to a predefined order and format of a transmission data string including a pen ID and a control signal (LS shown in FIG. 5 described later).
G signal).

In this embodiment, in each data bit, the "1" bit is formed in a modulation format having an interval twice as long as the "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 the redundancy is relatively high,
Six bits (64 pieces) of data are allocated to 108 codes of the same number of “1” and “0” and 10 or less consecutive “1” or “0” among 10-bit length codes. Encoding by the method.

By adopting 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, a pen pressure signal is “00”, an ID is “11”, etc.), with 24 bits as one block,
The next two bits are composed of these parities, and subsequently, 16-bit data and 2-bit parities are arranged to form one block of data.

When such data is encoded by the above-described method, a signal having a length of 40 bits is obtained. A 10-bit sync code is added to the head of the code. In this sync code, four “0” s and five “1s” continue or an inverted pattern thereof (the end of the immediately preceding block is
Using a special code of "1" or "0"), it is easy to identify the data word, and it is possible to reliably identify the position and restore the data even in the middle of the data string. Has become.

Therefore, one block is a transmission signal having a length of 50 bits, and a control signal and 16-bit data such as ID or writing pressure are transmitted. In this embodiment,
7.5 kHz of 1/8 of the first frequency of 60 kHz is used as the second frequency.
The average transmission bit rate is 2/3, that is, 5 kHz because the above-described encoding method is adopted. Further, since one block is 50 bits, 24 bits of data are transmitted at 100 Hz.

Therefore, the effective bit rate excluding the parity is 2000 bits / sec. As described above, although the redundancy is high, it is a method that can prevent erroneous detection and facilitate synchronization with a very simple configuration.

Also, by using a phase synchronization signal for sensor control described later and checking the repetition period of the 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 pen-up or double tap is performed can be surely performed by the presence or absence of the header signal.

FIG. 4 is a block diagram showing the internal configuration of the coordinate detector 1 shown in FIG. 1, and the same components as those in FIG. 1 are denoted by the same reference numerals. The operation of each unit will be described below with reference to the timing charts shown in FIGS.

In the figure, a 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 20X and 2OY for detecting an arrival direction of light by an imaging optical system. Is provided, and receives the diffused light from the light spot 5 generated on the screen 10 by the light beam from the light emitting element 41 built in the pointing tool 4.

The light receiving element 6 is provided with a condenser lens 6a (see FIG. 1) as a condenser optical system, and detects a light amount of a predetermined wavelength with high sensitivity from the entire range on the screen 10. After the detection output is detected by the frequency detection unit 71, the control signal detection unit 72 demodulates a digital signal including data such as a control signal (a signal superimposed by the light emission control unit 42 of the indicator 4).

FIGS. 5 and 6 show the coordinate detector 1 shown in FIG.
5 is a timing chart for explaining the operation of the control signal, and particularly corresponds to a timing chart of the operation of restoring the control signal.

In FIG. 5, a data signal composed of a bit string as described above is converted into a light output signal LSG by a light receiving element 6.
And detected by the frequency detecting means 71. The frequency detecting means 71 is configured to tune to the pulse cycle of the highest first frequency in the optical output signal LSG,
By using it together with an optical filter, the modulation signal CMD is demodulated without being affected by disturbance light.

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

The modulated signal CMD detected by the frequency detecting means 71 is interpreted as digital data by the control signal detecting means 72, and the above-described control signals such as pen-down and pen buttons are restored. The restored control signal is sent to the communication control means 33.

The code modulation cycle, which is the second frequency included in the modulation signal CMD, is detected by the sensor control means 31, and the signal is used to detect the period of the linear modulation.
X and 20Y are controlled.

That is, in the sensor control means 31, FIG.
Is reset at the timing of the header section (HEADER) shown in FIG. 1, and then a signal LCK synchronized with the falling edge of the modulation signal CMD is generated. Therefore, the generated signal LCK is a signal of a constant frequency synchronized with the presence or absence of light emission of the pointing device 4.

From the modulation signal CMD, a signal LON indicating the presence or 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 a 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 means 72 detects the header section and confirms that the input from the pointing device 4 has started, not other equipment or noise, and sends a signal indicating this confirmation to the communication control means 33. Is transmitted to the sensor control means 31 and 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 means 32 is started.

FIG. 6 is a timing chart at the end of the series of operations when the light output signal LSG disappears. When the modulation signal CMD detected from the light output signal LSG keeps the low level for a certain period of time, the presence or absence of light input is determined. Becomes low level, and the signal CON showing validity of the sensor operation also becomes low level. As a result, the output operation of the coordinates by the linear sensors 20X and 20Y ends.

FIG. 7 is a perspective view showing an arrangement relationship between two linear sensors 20X and 20Y provided in the coordinate detector 1 shown in FIG. 4, and the same components as those in FIGS. The code is attached.

In the figure, the image of the light spot 5 is formed as linear images 91X and 91Y on the photosensitive portions 21X and 21Y of the sensors by the cylindrical lenses 90X and 90Y as the image forming optical system.

By arranging these two sensors at right angles at right angles, an output having a peak at a pixel reflecting the X coordinate and the Y coordinate is obtained. And these 2
The four sensors are controlled by a sensor control unit 31 shown in FIG. 4, and an output signal is sent to a coordinate calculation unit 32 as a digital signal by an AD conversion unit 31A connected to the sensor control unit 31 to calculate an output coordinate value. The result is transmitted to an external control device (not shown) by a predetermined communication method via the communication control means 33 together with data such as a control signal from the control signal detection means 72.

In order to perform an unusual operation (for example, setting of a user calibration value) such as adjustment, the communication control unit 33 sends the sensor control unit 31 and the coordinate calculation unit 3.
A mode switching signal is sent to 2.

In the present embodiment, the focus is adjusted so that the image of the light spot 5 has an image width several times as large as the pixel of each sensor, and blur is intentionally caused. 1.5mm diameter
Plastic cylindrical lens and pixel pitch of about 15μ
According to experiments using a linear CCD with an effective pixel of 64 pixels and an infrared LED, the sharpest image was about 4
The image width becomes 15 μm or less over the entire angle of view of 0 °,
In such a state, it has been found that the pixel division calculation result is distorted in a stepwise manner.

Therefore, the image width is changed from “30” to “60” μm.
When the position of the lens was adjusted to the degree, 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.

Further, the use of a CCD having a small number of pixels and an appropriately blurred optical system is one of the points of the present embodiment. By using such a combination, the amount of operation data is small and small. An extremely high-resolution, high-accuracy, high-speed and low-cost coordinate input device can be realized by using a sensor and an optical system.

The linear sensor 20X for detecting the X coordinate and the linear sensor 20Y for detecting the Y coordinate, which are arranged in an array, have the same configuration, and the internal configuration is shown in FIG.

FIG. 8 is a block diagram illustrating the configuration of the linear sensor 20X for detecting the X coordinate and the linear sensor 20Y for detecting the Y coordinate shown in FIG.

In the figure, a sensor array 2 as a light receiving section
1 is composed of N pixels (64 pixels in this embodiment),
The charge corresponding to the amount of received light is stored in the integration unit 22. The N integrating units 22 can be reset by applying a voltage to the gate ICG, so that the electronic shutter operation can be performed. The electric charge stored in the integrating section 22 is applied to the electrode S
By applying a pulse voltage to T, the signal is transferred to the storage unit 23.

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 signal LCK synchronized with the light emission timing of the indicator 4. .

Thereafter, the electric charges separately accumulated in synchronism with the blinking of the light are transferred to the 2N linear CCD sections via the 2N shift sections 24 provided for simplifying the transfer clock. 25.

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 signal RCL, 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 accumulated charge amount. In practice, 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.

The linear sensors 20X, 20 obtained at this time
An example of the Y output waveform is shown in FIGS.

FIGS. 9 and 10 are characteristic diagrams showing an example of output waveforms of the linear sensors 20X and 20Y shown in FIGS. 4 and 7, wherein the vertical axis indicates the output level.

In FIG. 9, the waveform B is a waveform when only the signal when the light emitting element 41 is turned on is read, 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. 8, the charges of the 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 (B-A waveform) of the adjacent charge amount, thereby obtaining the signal of only the light from the indicator 4. And stable coordinate input can be performed without being affected by disturbance light (noise).

If the maximum value of the waveform B-A shown in FIG. 9 is defined as a PEAK value, if the accumulation time during which the sensor functions for light is increased, the PEAK value is changed according to the time.
The value increases.

In other words, if the time corresponding to one cycle of the signal LCK is defined as a unit accumulation time, and the number of accumulations n is defined in units of the accumulation time, the PEAK value increases by increasing the number of accumulations n, and this PEAK value increases. By detecting that a predetermined magnitude (threshold value TH1 to be described later) has been reached, 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, the sensor is provided with a skim portion 28 having a skim function.

The skim unit 28 monitors the level of the non-lighting signal. In FIG. 10, when the signal level exceeds a predetermined value at the n-th An (in FIG. 10, a dashed line in the figure), a predetermined amount of electric charge is generated. A pixel is extracted from each of A and B pixels.

As a result, at the next (n + 1) -th time, An +
The waveform shown in FIG. 1 is obtained. By repeating this waveform, signal charges can be continuously stored without saturation even when extremely strong disturbance light is present.

Therefore, even if the amount of blinking light is weak,
By continuing the integration operation many times, a sufficiently large signal waveform can be obtained.

In particular, when a light emitting source in the visible light range is used for the indicator 4, a signal of a display image is superimposed. Therefore, by using the above-described skim function and difference output, a sharp waveform with very little noise is obtained. It becomes possible.

FIG. 11 is a flowchart showing an example of a first data processing procedure in the coordinate input device according to the present embodiment.
This corresponds to a series of operation procedures of sensor control of 0X and 20Y. Note that (1) to (11) indicate each step.

When the sensor control means 31 starts the sensor control operation, in step (1), the signal CO shown in FIG.
Monitor N. When the signal CON goes high, the flag pon is set to "1" in step (2), the number of accumulations n is reset to "0", and step (3)
It is determined whether or not the PEAK value (peak level) of the sensor output is larger than a predetermined value (threshold value TH1). If it is smaller than the threshold value TH1, it is determined in step (4) that the number of accumulations n Is determined to have exceeded the first predetermined number n0. If it is determined that the number has not exceeded the predetermined number n0, the process proceeds to step (5), the number of accumulations n is incremented by "1", and the process returns to step (3).

On the other hand, in step (3), when the PEAK value is T
If it is determined that it is larger than H1, and if it is determined in step (4) that the number of accumulations n exceeds the first predetermined number of times n0, the process proceeds to step (6) and the integration stop signal RON is set to the high level (H ), The integration operation is stopped. Then, the coordinate value calculation processing by the coordinate calculation means 32 is started.

Thereafter, step (7) and step (8)
If it is determined that the second predetermined number of times n1 has been exceeded in the loop of (2), in step (9), the integration stop signal RON goes low, and at the same time, several times the period of the signal LCK (the example in FIG. 6). In this case, the sensor reset signal RCL becomes high level, the process proceeds to step (10), and the signal CON is reset.
Are determined to be at the high level, the operations of steps (2) to (10) are repeated, and the coordinate value calculation is performed at intervals determined by the predetermined number n1.

On the other hand, if it is determined in step (10) that the signal CON is at low level, the state is maintained only once even if the signal CON drops due to the influence of dust or the like. In step (11), the process waits for one cycle time and returns to step (1). If it is determined that the signal CON is at the low level for two consecutive periods, the process returns from step (1). Proceed to step (12)
The flag pon is reset to “0”, the state is set to a wait state for a sync signal, and the process returns to step (1).

As shown in step (1), this dropout countermeasure portion can be longer than one cycle, and needless to say, may be eliminated if there is little disturbance.

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 1 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 this embodiment, even in such a case, the number of integrations automatically follows, and a stable output signal can always be obtained, so that an excellent coordinate detection becomes possible. The effect is obtained.

When the beam of the laser pointer is incident on the sensor without being scattered much, considerably intense light enters, but it is clear that stable coordinates can be detected even in such a case. is there.

Further, the LE used by directly contacting the screen is used.
When a pen type using D and a laser pointer are used together, LEDs with a larger light amount can be used. Therefore, the number of integrations n0 and n1 shown in FIG. It is also possible to switch the sampling speed in the case of a pen and the sampling speed in the case of a pointer.

Actually, a delicate drawing operation like character input is impossible 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. And the imaging 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 an operation can be easily performed 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 means has exceeded a predetermined level and stopping the integration operation is provided, the signal of the light spot image having a substantially constant level even if the light amount changes. Can be created, whereby a stable and high-resolution coordinate calculation result can always be obtained.

Hereinafter, a coordinate calculation process in the coordinate calculation means 32 shown in FIG. 4 will be described.

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 the AD conversion means 31A provided in the sensor control means 31, and are used as coordinate calculation means. 32, and the coordinate values are calculated. First, the calculation of the coordinate value is performed by X
Coordinate values (X1, Y1) on the sensor are obtained for output data in each direction of the coordinate and the Y coordinate. The arithmetic processing is the same as X and Y, so only X will be described.

FIG. 12 is a flowchart showing an example of a second data processing procedure in the coordinate input device according to the present embodiment, and corresponds to a coordinate calculation processing procedure in the coordinate input device 32. Note that (1) to (10) indicate each step.

First, in step (1), the counter con
t is initialized to “0”, and in step (2), 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 described later).
(N) (the number of pixels n = 64 in the present embodiment) is read and stored in, for example, a buffer memory (not shown) in the coordinate calculation means 32.

Next, in step (3), a data value Ex (n) that is equal to or larger than the threshold value is derived by comparing with a threshold value V set in advance. Using this data, the coordinates X1 on the sensor are calculated in step (4).

In this embodiment, the centroid of the output data is calculated by the centroid method, but the output data Ex (n)
Needless to say, there are a plurality of calculation methods such as a method of obtaining the peak value of (for example, by a differentiation method).

Next, in step (5), it is determined whether or not the mode of the coordinate calculation processing is the reference point setting mode, and if YES, the counter cont is determined in step (8).
Is incremented by “1”, and in step (9), it is determined whether the content of the counter cont is “2” or more.
If YES, the process ends.

On the other hand, if NO is determined in step (9), in step (10), the center of gravity value of the X-direction sensor obtained at each point is calculated as X11 and X12. , Known coordinate values α1 and α2 are stored in the buffer, and the process returns to step (2).

On the other hand, if it is determined in step (5) that the mode is not the reference point setting mode, in step (6), in step (10), the value should be derived using the value stored in the buffer. The X coordinate of the coordinate input point is calculated based on the following equation (1). And step (7)
In order to provide a high-performance coordinate input device, coordinate values are calibrated as needed (for example, the distortion is corrected by a software operation to correct the lens aberration of the optical system). , Determine the coordinate value, output the coordinate value,
The process ends.

Hereinafter, in order to calculate the 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 using the X direction as an example.

First, the pointing tool 4 is positioned at points (α1, β1) and (α2, β2) on the screen 10 where the X coordinate and the Y coordinate are known, and the above-described steps (2) to (4) are performed. The respective processes are performed, the barycentric values of the X-direction sensor obtained at each point are derived as X11 and X12, and the values and the known coordinate values α1 and α2 are stored in step (10).
At the time of ordinary coordinate calculation using the stored values, the X coordinate of the coordinate input point is calculated based on the following equation (1).

[0108]

X = (X1−X1 ₁ ) (α ₂ −α ₁ ) / (X1 ₂ −X1 ₁ ) + α ₁ (1) In step (7), a higher-performance coordinate input device is provided. For this purpose, the coordinate values are corrected as necessary (for example, the distortion is corrected by a software operation to correct the lens aberration of the optical system), and the coordinate values are determined.

Note that it is possible to output the determined coordinates as they are in real time, or to thin out data according to the purpose (for example, to output only one data for every ten determined coordinates). Needless to say, this is important when the following specifications are assumed.

The stability of the user's hand is different between the case where the pointing tool 4 is used like a pen and the case where the pointing tool 4 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 necessary to follow as fast and faithfully as possible. Especially when writing characters, if a small quick operation is not possible, it becomes impossible to input correctly.

In the present embodiment, since the ID is transmitted by the control signal, it is possible to determine whether or not the pointer is of the pointer type and whether or not the tip switch is pressed. Can be determined.

If the pointer is a pointer, for example, the output coordinate values (X-1, Y-1), (X-2, Y
By calculating the moving average by using -2) and obtaining the current output coordinate values (X, Y), a configuration with less blur and good operability can be obtained.

In the present embodiment, a simple moving average is used, but the function used for such smoothing processing is as follows.
In addition, various methods such as non-linear compression of the absolute value of the difference according to the magnitude, and non-linear compression of the difference from the predicted value by the moving average using the predicted value can be used. In short, when using as a pointer, it is possible to increase the level of smoothing, otherwise switch to a level of weakness by using a control signal. However, the effect of the present invention is great.

Note that, as described above, when the coordinate sampling frequency is 100 Hz, these calculation
msec, the original data is 64 pixels x
Since 2 (x and y) × AD conversion means are as small as 8 bits and no convergence operation is required, a low-speed 8-bit one-chip microprocessor can sufficiently perform 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, unlike the case of using an area sensor, there is no need to develop a dedicated LSI for performing high-speed image data processing, and the advantages such as development cost and development period are very large.

The data signal indicating the coordinate value (X, Y) obtained by the above-described arithmetic processing is supplied to the coordinate arithmetic means 32.
Is sent to the communication control means 33. This communication control means 3
3, the data signal and the control signal from the control signal detecting means 72 are input. The data signal and the control signal are both converted into a communication signal of a predetermined format and sent to an external display control device. This allows
Various operations such as input of a cursor and menu on the screen 10 and input of characters and line drawings can be performed. As described above, even when a sensor with 64 pixels is used, a resolution of more than 1000 and sufficient accuracy can be obtained, and both the sensor and the optical system can be configured in a small and low-cost configuration, and the arithmetic circuit is very small. A coordinate input device that can have a large-scale configuration can be obtained.

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 configuring the sensor 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 embodiment,
Signals of the light spot blinking at a predetermined cycle by the indicator 4 at the time of lighting and at the time of non-lighting are separately integrated to obtain a difference signal,
Since the position of the peak pixel was determined with high accuracy,
A highly accurate and high-resolution coordinate value can be obtained, and furthermore, the influence of disturbance light can be suppressed, and a compact, lightweight, and low-cost coordinate input device can be realized.

According to the above-described embodiment, by attaching the rotatable transparent spherical lens 11 to the tip of the pointing tool 4, the pointing tool 4 is pressed against the screen 10 to write characters and lines. Friction between the screen and the screen 10 can be reduced, and a smooth pen input operation can be performed without scratching the tip of the pointing tool 4 or the surface of the screen 10.

Hereinafter, the configuration of a data processing program that can be read by a storage medium provided in the coordinate input device according to the present invention will be described with reference to a memory map shown in FIG.

FIG. 13 is a diagram for explaining a memory map of a storage medium for storing various data processing programs readable by the coordinate input device according to the present invention.

Although not shown, information for managing a group of programs stored in a storage medium, for example, version information, a creator, etc., is also stored, and information dependent on an OS or the like on the program reading side, for example, a program is stored. An icon or the like for identification display may also be stored.

Further, data dependent on various programs is also managed in the directory. Also, a program for installing various programs on a computer, and a program for decompressing a program to be installed when the program to be installed is compressed, may be stored in some cases.

The functions shown in FIGS. 11 and 12 in this embodiment may be performed by a host computer by a program installed from the outside.
In this case, the present invention is applied even when a group of information including a program is supplied to the output device from a storage medium such as a CD-ROM, a flash memory, or an FD, or from an external storage medium via a network. Things.

As described above, the storage medium storing the program codes of the software for realizing the functions of the above-described embodiments is supplied to the system or the apparatus, and the computer (or CPU or MP) of the system or the apparatus is supplied.
It goes without saying that the object of the present invention is also achieved when U) reads and executes the program code stored in the storage medium.

In this case, the program code itself read from the storage medium realizes the novel function of the present invention, 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, C
DR, magnetic tape, nonvolatile memory card, RO
M, EEPROM and the like can be used.

When the computer executes the readout program code, not only the functions of the above-described embodiment are realized, but also the OS (Operating System) running on the computer based on the instruction of the program code. ) And the like perform part or all of the actual processing, and the processing realizes 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, The CPU provided in the function expansion board or function expansion unit performs part or all of the actual processing,
It goes without saying that a case where the function of the above-described embodiment is realized by the processing is also included.

[0130]

As described above, the first embodiment according to the present invention is described.
According to the invention, a coordinate input indicator for irradiating light emitted from the light emitting element on the coordinate input screen and inputting the coordinate position, on the optical path of the light emitted from the light emitting element, In addition, since a spherical lens for forming a spot light with the light is rotatably provided at the tip of the pointing tool, the pointing tool is smoothly moved without any trouble even when the spherical lens is brought into contact with the coordinate input screen. Thus, the coordinate position intended by the user can be indicated.

According to the second aspect, the rotatable spherical lens is provided at an isolated position without directly contacting the light emitting element, so that the light emitting element is not damaged by the rotation of the lens, and Thus, the scattered spot light can be reliably emitted without being affected by the angle between the pointing tool and the coordinate input screen.

In the third invention according to the present invention, since a plurality of switches for inputting a plurality of different pieces of information are provided at predetermined positions, various information can be operated by pressing the scattered spot light and each switch. You can type well.

A fourth invention according to the present invention is a coordinate input device for determining coordinate input information by detecting a spot light emitted from a pointing tool penetrating a coordinate input screen, wherein the spot input device specifies the coordinate input screen. Detecting means for detecting light; calculating means for performing a predetermined calculating process on the position information detected by the detecting means to calculate the coordinate position; and displaying the coordinate position calculated by the calculating means on the coordinate input screen. Control means for reflecting the light in the instruction, so that the spot light is detected from the indicator without being influenced by external light, and is not affected by disturbance light, and the spot light emitted from the indicator is The position can be specified reliably.

Therefore, even in a use environment that is susceptible to disturbance light, friction caused by movement on the designated screen is reduced, and the influence of disturbance light is suppressed. It is possible to provide a small-sized and low-cost pointing device and a coordinate input device for inputting coordinates, which can input information.

[Brief description of the drawings]

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

FIG. 2 is a cross-sectional configuration diagram illustrating details of the pointing device shown in FIG. 1;

FIG. 3 is a view showing an operation mode of the pointing device shown in FIG. 2;

FIG. 4 is a block diagram showing an internal configuration of the coordinate detector shown in FIG.

FIG. 5 is a timing chart for explaining the operation of the coordinate detector shown in FIG. 4;

FIG. 6 is a timing chart for explaining the operation of the coordinate detector shown in FIG. 4;

FIG. 7 is a perspective view showing an arrangement relationship between two linear sensors provided in the coordinate detector shown in FIG. 4;

8 shows a linear sensor for detecting the X coordinate shown in FIG. 7, Y
FIG. 3 is a block diagram illustrating a configuration of a linear sensor for detecting coordinates.

FIG. 9 is a characteristic diagram showing an example of an output waveform of the linear sensor shown in FIGS. 4 and 7;

FIG. 10 is a characteristic diagram showing an example of an output waveform of the linear sensor shown in FIGS. 4 and 7;

FIG. 11 illustrates a first example of the coordinate input device according to the present embodiment.
9 is a flowchart illustrating an example of a data processing procedure.

FIG. 12 illustrates a second example of the coordinate input device according to the embodiment.
9 is a flowchart illustrating an example of a data processing procedure.

FIG. 13 is a diagram illustrating a memory map of a storage medium that stores various data processing programs that can be read by the coordinate input device according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Coordinate detector 2 Coordinate detection sensor part 3 Controller 4 Indicator 5 Light spot 6 Light receiving element 7 Signal processing part 8 Projection display device 10 Screen 11 Spherical lens 20X, 20Y Linear sensor 21 Sensor array 22 Integrator 25 Linear CCD part 26 Ring CCD unit 27 CLR unit 28 Skim unit 29 Amplifier 31 Sensor control unit 32 Coordinate calculation unit 33 Communication control unit 41 Light emitting element 42 Light emission control unit 43 Operation switch 44 Power supply unit 45 Light beam 71 Frequency detection unit 72 Control signal detection unit 81 Image Signal processing unit 82 Liquid crystal panel 83 Lamp 84 Mirror 85 Condenser lens 86 Projection lens

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Katsuhide Hasegawa, Inventor 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Katsuyuki Kobayashi 3-30-2, Shimomaruko, Ota-ku, Tokyo Canon Inside (72) Inventor Atsushi Tanaka 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Masaaki Kinpu 3-30-2, Shimomaruko 3-chome, Ota-ku, Tokyo Inside Canon Inc. F term (reference) 5B087 AA02 AC09 AE03 BC03 BC13 BC17 BC32 CC09 CC20 CC21 CC26 CC33 DD03

Claims (4)

[Claims] 1. A coordinate input indicator for inputting a coordinate position by irradiating light emitted from a light emitting element onto a coordinate input screen, and on a light path of light emitted from the light emitting element, and A pointing tool for inputting coordinates, wherein a spherical lens for forming a spotlight by the light is rotatably provided at a tip of the pointing tool. 2. The pointing tool for inputting coordinates according to claim 1, wherein the rotatable spherical lens is provided at a position separated from the light emitting element without directly contacting the light emitting element. 3. The pointing device according to claim 1, wherein a plurality of switches for inputting a plurality of different pieces of information are provided at predetermined positions. 4. A coordinate input device for detecting spot light emitted from a pointing tool penetrating a coordinate input screen to determine coordinate input information, comprising: detecting means for detecting a spot light indicating the coordinate input screen; A calculating means for performing a predetermined calculating process on the position information detected by the detecting means to calculate a coordinate position; a controlling means for reflecting the coordinate position calculated by the calculating means on an instruction on the coordinate input screen; A coordinate input device comprising: