JP2000207118A - Coordinate input indicator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the operability and handleability of a coordinate input indicator for an optical coordinate input device. SOLUTION: This indicator 4 is provided with a light-emitting means 41A for emitting invisible infrared light and a light-emitting means 41B for emitting visible infrared light as a light-emitting means for irradiating a coordinate input plane with a light spot for an coordinate input, a light emission control part 44, and manual operating switches 43A-43D. The light emission control part 44 selectively emits the light-emitting elements 41A and 41B, corresponding to the operation of the switches 43A and 43B. Thus, the visible light and invisible light can selectively be emitted for the radiation of light spot, and the visible light and invisible light are selectively used as needed, so that the operability and handleability of the coordinate input indicator can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coordinate input pointing device, and more particularly, to a coordinate for pointing an arbitrary position on a coordinate input surface of an optical coordinate input device and irradiating a light spot to input coordinates. It relates to an input pointing device.

[0002]

2. Description of the Related Art The above-mentioned optical coordinate input device is used, for example, in a large-sized display system configured to allow input of coordinates. In this large display system, the display screen of the large display is configured to also serve as a coordinate input surface,
An arbitrary position on the display screen is designated by a coordinate input indicator (hereinafter abbreviated as an indicator) provided with a light emitting means, and a coordinate input is performed by irradiating a light spot by the light emission of the light emitting means to perform external connection. Control your computer,
It is designed to input characters and figures.

As a conventional coordinate input device used in such a large display system, a light spot on a display screen is imaged using a CCD area sensor or a linear sensor.
Image processing such as using barycentric coordinates or pattern matching to calculate and output coordinate values;
Devices using a position detecting element called SD (an analog device that can obtain an output voltage corresponding to the position of a light spot) are known.

[0004] For example, Japanese Patent Publication No. 7-76902 discloses an apparatus for detecting a coordinate by imaging a light spot by a parallel beam of visible light from a light emitting means provided on an indicator with a video camera. . In addition, Japanese Unexamined Patent Publication
Japanese Unexamined Patent Publication No. 274266/1995 discloses an apparatus for performing coordinate detection using a linear CCD sensor and a special optical mask.

The above-described coordinate input device is applied to a front-type or rear-type projection display device having a large screen of about the size of a blackboard, and is used as an input device of a computer to which the projection display device is connected. . That is, the coordinates of the input point, which is the irradiation position of the light spot by the light beam from the pointing device, are detected by the coordinate detecting means, and output to the computer from the coordinate detecting means. A predetermined function, for example, execution of a menu command is performed by the computer based on the output result of the coordinates of the input point. Of course, a cursor can be displayed at the position of the input point. In addition, displaying a point at the position of the input point, or, when the input is made continuously, connecting the input point group detected at a predetermined sampling rate with a line to display the locus of the input point Can also. Furthermore, by identifying and determining the trajectory, recognition of a character or a figure, execution of a gesture command, and the like can be performed. In addition, a switch corresponding to a mouse button is provided on the pointing device, and by operating this switch, the designated menu command or icon can be selected or executed. In this case, various mouse-compatible applications can be operated by the pointing device.

A large-screen projection display device having the above-described coordinate input means is used for a meeting in a conference room, a video conference, or a so-called presentation.

[0007]

However, the above-mentioned conventional coordinate input device has the following problems regarding the usability and operability of the pointing device.

First, when the light emitting means of the pointing device emits visible light, a display screen (coordinate input surface) of the projection display device is used.
There is a problem in that the position of the light spot visible to the user's eyes and the position of the input point detected by the coordinate input device are shifted. The amount of this shift is due to the detection accuracy of the coordinate input device and the distortion of the display screen of the projection display device. The amount of the shift is calibrated by, for example, calibrating a light spot on a predetermined point on the screen. Can be made smaller, but not eliminated. Due to the displacement, the position of the light spot and the position of the cursor displayed on the screen or the position of the locus corresponding thereto are displaced, and the usability becomes extremely poor when selecting or drawing a menu command or icon.

On the other hand, when the light emitting means of the pointing device emits an invisible light ray such as infrared light, the light spot on the display screen due to the light is invisible to the user, so that the above-mentioned problem does not occur. However, in this case, when operating the pointing device at a location more than a predetermined distance from the display screen, a light spot is located outside the display screen, coordinates cannot be detected, and the pointing position of the pointing device is completely unknown. There is a problem that there is. At the distant position as described above, the light spot comes out of the display screen due to a slight difference in the direction of the light beam emitted from the pointing device, so that the operation of the pointing device requires skill. Invites evil.

[0010] Even when the light spot is located in the display screen, if the image information on the screen is large or complicated, or if the cursor displayed corresponding to the light spot is small or inconspicuous, There is a problem that it is difficult to find the position of the cursor and the usability is poor.

An object of the present invention is to provide a coordinate input pointing device of this type which solves the above-described problems and improves operability.
An object of the present invention is to provide a configuration that can improve usability.

[0012]

According to the present invention, an arbitrary position on a coordinate input surface of an optical coordinate input device is designated to irradiate a light spot to input a coordinate. A coordinate input indicator for performing, a first light emitting unit that emits visible light for irradiating the light spot;
A second light source that emits invisible light for irradiating the light spot;
And a light emission control means for selectively causing the first light emission means and the second light emission means to emit light.

The invisible light is, for example, infrared light. The light emission control means selectively emits light from the first light emission means and the second light emission means in response to, for example, an operation of a manual switch.

According to such a configuration, it is possible to selectively emit visible light and invisible light for irradiating a light spot. Operability and usability can be improved.

[0015]

Embodiments of the present invention will be described below with reference to the drawings. Here, an embodiment of a coordinate input indicator of an optical coordinate input device which constitutes a large display system together with a projection display device will be described.

First, FIG. 2 shows the overall configuration of a large display system. The system includes a screen 10 constituting a coordinate input surface together with a display screen, an indicator 4 for pointing an arbitrary position on the screen 10 and irradiating a light spot 5 to input coordinates, and a light spot 5 And a projection type display device 8 for projecting a display image on a screen 10. Note that the coordinate detector 1, the pointing device 4, and the screen 10 constitute a coordinate input device. Hereinafter, the respective configurations of the projection display device 8, the coordinate detector 1, and the pointing device 4 will be described in this order.

<Description of Projection Display 8> The configuration of the projection display 8 will be described with reference to FIG.

In FIG. 2, a projection type 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 computer (not shown) is input.
And a liquid crystal panel 82 controlled thereby to form an image
, Lamp 83, mirror 84, condenser lens 85
, And a projection lens 86 for projecting an image on the liquid crystal panel 82 onto the screen 10. Thus, a desired image can be displayed on the screen 10 which is a large screen.

The screen 10 is irradiated with a light spot 5 by a light beam 45 emitted from the pointing tool 4 (an infrared light beam 45A or a visible light beam 45B as invisible light, which will be described later). The screen 10 has an appropriate light diffusing property in order to widen the observation range of the projected image, and the light beam 45 from the pointing tool 4 is also diffused at the position of the light spot 5. Therefore, light spot 5 on the screen
Part of the light diffused at the position of the light spot 5 enters the coordinate detector 1 irrespective of the position of the light spot 45 and the direction of the light beam 45, and the coordinates of the irradiation position of the light spot 5 can be detected by the coordinate detector 1. It has become.

<Description of Coordinate Detector 1> The configuration of the coordinate detector 1 will be described with reference to FIGS. First, the schematic configuration will be described with reference to FIG.

In FIG. 2, a coordinate detector 1 includes a coordinate detection sensor unit 2, a controller 3 for controlling the sensor unit 2 and calculating coordinates, a light receiving element 6 as a control signal detection sensor, and an output signal thereof. Signal processing unit 7 for detecting a pen down or pen button control signal to be described later
It consists of Then, the coordinates of the light spot 5 on the screen 10 and a control signal corresponding to the state of each switch of the indicator 4 described later are detected, and the controller 3 communicates with an external connection device (not shown) such as a computer. I am trying to do it. This allows the user to freely enter characters and line drawings on the screen 10 and to perform input operations such as button operation and icon selection determination using the indicator 4.

Next, a more detailed configuration of the coordinate detector 1 will be described with reference to FIG. As shown in FIG. 1, 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 a detector 2 for detecting the arrival direction of light by an imaging optical system.
And two linear sensors 20X and 20Y.
The linear sensors 20X and 20Y correspond to the coordinate detection sensor unit 2 in FIG. These are the light beams 45 from the pointing device 4.
Respectively, the diffused light from the light spot 5 irradiated on the screen 10 is received.

The light receiving element 6 is provided with a condenser lens 6a (see FIG. 2) as a condenser optical system.
The light emitting elements 41A, 41A,
The light amount of the emission wavelength of 41B is detected with high sensitivity. 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 on the emission signal by the emission control unit 44 of the indicator 4). Is done. The frequency detector 71 and the control signal detector 72 correspond to the signal processor 7 shown in FIG.
Is configured.

Next, the two linear sensors 20X and 20Y
Will be described with reference to FIGS.

FIG. 3 shows two linear sensors 20X, 20X.
7 shows an arrangement relationship between Y and the imaging optical system. As shown here,
The image of the light spot 5 illuminated on the screen 10 by the pointing tool 4 is converted into cylindrical lenses 90X, 9
0Y, the photosensitive portions 21 of the linear sensors 20X and 20Y
X and 21Y are formed as linear images 91X and 91Y. These two sensors 20X, 20Y and the cylindrical lens 9
By arranging 0X and 90Y exactly at right angles, an output having a peak at a pixel reflecting the X coordinate and the Y coordinate respectively can be obtained. These two sensors are controlled by a sensor control unit 31, and an output signal is sent as a digital signal to a coordinate calculation unit 32 by an AD conversion unit 31 A connected to the sensor control unit 31, where the output coordinate value is calculated. Is done.

The output coordinate value from the coordinate calculation unit 32 and data such as a control signal from the control signal detection unit 72 are input to the communication control unit 33, and are externally controlled by a predetermined communication method such as a computer. It is sent to a device (not shown). Further, in order to perform an unusual operation (for example, setting of a user calibration value) such as adjustment, a mode switching signal is sent from the communication control unit 33 to the sensor control unit 31 and the coordinate calculation unit 32.

The sensor control unit 31 and the AD conversion unit 31
A, the coordinate calculation unit 32, and the communication control unit 33 constitute the controller 3 in FIG.

FIG. 4 shows the linear sensors 20X and 20Y.
2 shows the internal configuration of FIG. These linear sensors 20X, 20Y
Are arranged in an array and can perform a synchronous integration operation. Since the two sensors for the X coordinate and the Y coordinate have the same configuration, the configuration will be described without distinction for the X coordinate and the Y coordinate.

The sensor array 21 serving as a light receiving section is composed of N pixels, and the charge corresponding to the amount of received light is stored in the integrating section 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 integration unit 22 is transferred to the storage unit 23 by applying a pulse voltage to the electrode ST. The storage unit 23 is composed of 2N units, and is H (high level) of the signal LCK synchronized with the blinking of light.
, And L (low level). 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 signal RCL, the charges from the linear CCD unit 25 are sequentially accumulated. The charges thus accumulated are read by the amplifier 29. The amplifier 29 is non-destructive and outputs a voltage proportional to the accumulated charge amount. Actually, the difference between adjacent charge amounts, that is, the charge amount at the time of lighting is subtracted from the charge amount at the time of lighting. The minute value is amplified and output.

<Description of Pointing Tool 4> Next, the configuration of the pointing tool 4 will be described with reference to FIGS.

In FIG. 1, a pointing device 4 includes a light emitting element 41A composed of a semiconductor laser that emits infrared light that is invisible light, and a semiconductor that emits visible light, as a light emitting element for irradiating the light spot 5 described above. A light emitting element 41B made of a laser is provided. Further, the light emitting element 41A
, A light-emitting driver 42B that drives the light-emitting element 41B, and a light-emitting driver 42B that drives the light-emitting element 41B.
2A, 42B, that is, the light emitting elements 41A,
A light emission control unit 44 for controlling light emission of 1B and four manual operation switches 43A to 43D are provided. The light emission control unit 44 controls the light emitting element 4 according to the on / off state by the pressing operation of the four operation switches 43A to 43D.
On / off of light emission of 1A or 41B and light emission control for superimposing a control signal on a light emission signal are performed.

Although not shown, the pointing device 4 is provided with an optical system for collimating or converging the infrared light and the visible light emitted by the light emitting elements 41A and 41B, respectively, to form light beams 45A and 45B (see FIG. 5). And a built-in power supply battery.

FIG. 5 is an external view of the pointing device 4. As shown here, the infrared light beam 4
A light beam 45B of 5A or visible light is emitted. The four operation switches 43A to 43A are provided on the outer periphery near the tip.
3D is arranged.

Table 1 below shows operation switches 43.
The operation modes of the pointing device 4 under the control of the light emission control unit 44 in accordance with the operations of A to 43D are shown. Table 1
The middle switches A, C, and D are operating switches 43A, 4
3C and 43D. In addition, “light emission” of “infrared light emission” corresponds to a light emission signal for light emission (a coordinate signal for coordinate input only), and “pen down” and “pen button” are a pen down and a pen button superimposed on the light emission signal. Corresponding to the control signal. In Table 1, the operation switch 4
Although there is no switch B column corresponding to 3B, if the switch A column is directly replaced with the switch B column, the "infrared light emission" column becomes the "visible light emission" column as it is.

[0036]

[Table 1]

Next, the operation and operation of the pointing device will be described. At the time of inputting coordinates, the operator grasps the pointing tool 4 and turns the tip of the pointing tool toward the screen 10. At this time, the switch 43
A and the switch 43B are arranged at positions where the thumb naturally touches. By pressing the switch 43A, the light emitting element 41A is driven (emitted), and an infrared light beam 45A is emitted. Further, by pressing the switch 43B, the light emitting element 41B is driven to emit a visible light beam 45B. The light spot 5 is irradiated on the screen 10 by these light beams 45A or 45B. This light is emitted as a light emission signal (coordinate signal) modulated by a predetermined method as described later. By pressing the switches 43C and 43D arranged at positions where the forefinger and the middle finger naturally touch, the control signals for pen down and pen button are output as signals superimposed on the light emission signal as shown in Table 1 above. .

<Description of Control Signal Demodulation> Next, an operation of restoring a control signal from an output signal of the light receiving element 6 in the coordinate detector 1 will be described with reference to FIG. FIG. 6 is a timing chart for explaining the operation of restoring the control signal.

When the switch 43A or the switch 43B of the indicator 4 is turned on, light emission is started. Due to the flashing of the light emission, a signal of a reader unit composed of a relatively long continuous pulse train and a signal of a header unit composed of a code (a maker ID or the like) following the leader unit are output first.
A transmission data string including D and a control signal according to the operation of the switch 43C or the switch 43B is sequentially transmitted in a predetermined order and format. In each data bit, the "1" bit is modulated in a modulation format such that it has a double interval with respect to the "0" bit.

The data signal composed of such a bit string is detected by the light receiving element 6 shown in FIG. The light output signal LSG detected by the light receiving element 6 is detected by the frequency detector 71. The frequency detector 71 is tuned to the pulse cycle of the highest first frequency in the optical output signal LSG, and is used in combination with an optical filter so that the modulation signal CMD is not affected by disturbance light. Is demodulated.

This detection method is the same as a widely used infrared remote controller, and is a highly reliable wireless communication system. In the present embodiment, as the first frequency, 60 KHz which is a band higher than that of a generally used infrared remote controller is used, and no malfunction occurs even when used at the same time. Note that the first frequency can be set to the same band as that of a generally used infrared remote controller. In such a case, malfunction can be prevented by identifying the first frequency with an ID or the like.

The modulation signal CMD detected by the frequency detection unit 71 is interpreted as digital data by the control signal detection unit 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 unit 33.

Although various data encoding methods can be used, it is desirable that the average light amount is constant for coordinate detection, and the PLL is tuned as described later. It is desirable that the clock component be sufficiently large. Since the amount of data to be transmitted is not so large, there is no problem even if the redundancy is relatively high. In consideration of these points, in the present embodiment, 6 bits (64 bits) are used.
) Of the 10-bit-length code, the number of 1s and 0s is the same, and the number of consecutive 1s or 0s is 3 or less.
It is encoded by the method of assigning to each code. 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. Such an encoding method is often used in a magnetic recording / reproducing apparatus and the like, and encoding and decoding can be easily realized by a similar method.

The above-mentioned 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, the ID is 11, etc.), and the next two bits are These parities are followed by 16 bits of data and 2
Bit parity is arranged to form one block of data. When such data is encoded by the above-described method, a 40-bit signal is added. A 10-bit sync code is added to the head of the signal. 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 2000 bits / second. 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. 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.

<Description of Linear Sensor Control> Next, control of the linear sensors 20X and 20Y will be described with reference to FIGS.

The code modulation cycle, which is the second frequency included in the modulation signal CMD shown in FIG.
1 is detected. The detected signal is used for controlling the linear sensors 20X and 20Y.

That is, the sensor control section 31 resets at the timing of the header section shown in FIG. 6, and then generates a signal LCK synchronized in phase with the fall of the modulation signal CMD. Based on the generated signal LCK, the sensor control unit 31 has a signal of a constant frequency synchronized with the presence or absence of light emission. 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 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, when the control signal detecting section 72 detects the header section and confirms that the input from the pointing device 4 has been started instead of other equipment or noise, 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. 7 shows a timing chart when the light output signal LSG is lost and a series of restoring operations is completed. Modulated signal CM detected from optical output signal LSG
When D keeps the low level for a certain period of time or more, the signal LON indicating the presence or absence of the light input becomes low level, and the signal CON indicating the validity of the sensor operation also becomes low level. As a result, the coordinates by the linear sensors 20X and 20Y The signal output operation ends.

FIG. 8 is a flowchart showing a series of operations of sensor control of the linear sensors 20X and 20Y by the sensor control section 31. First, the sensor control unit 31 starts a sensor control operation in step S101, and proceeds to step S1.
At 02, the signal CON is monitored. And the signal CO
When N becomes a high level, the flag p is determined in step S103.
On is set to 1 and the counter n is reset to 0. In step S104, it is determined whether or not the peak level PEAK of the sensor output is larger than a predetermined value TH1.

If less than TH1, step S10
At 5, it is determined whether the counter n has exceeded a first predetermined number n0. If it does not exceed, the process proceeds to step S106, and after a time corresponding to one cycle of the signal LCK, the counter n is incremented by 1 and the process returns to step S104. And PE
If the AK value is greater than TH1 or if n exceeds n0, the process proceeds to step S107, where the integration stop signal RON is set to a high level (H), whereby the integration operation is stopped. Then, the coordinate value calculation process by the coordinate calculation unit 32 is started.

Thereafter, step S108 and step S1
When the counter n exceeds the second predetermined number n1 in the loop 09, the integration stop signal RON is set to low level in step S110, and at the same time, the sensor reset signal is output for several times (two times in FIG. 7) the period of the signal LCK. RCL is set to the high level, and the process proceeds to step S112 to determine whether the signal CON is at the high level. This operation is repeated while the signal CON is at the high level, and the coordinate value calculation is performed for each cycle determined by the counter value n1. Done.

Step S111 is provided so that the state is maintained only once even if the signal CON drops due to the influence of dust or the like. If the signal CON is low in step S112, then step S111 is executed. After waiting for one cycle time determined by the counter value n1, the process returns to step S102 to determine whether the signal CON is at a high level.
If the signal CON is at the low level for two consecutive periods, the process proceeds from step S102 to step S113, resets the flag pon to 0, waits for a sync signal, and returns to step S101.

The dropout countermeasure portion can be longer than one cycle, and needless to say, may be eliminated 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.

<Description of integration operation of linear sensor>
The synchronous integration operation of the linear sensors 20X and 20Y will be described with reference to FIG.

FIG. 9 shows an example of output waveforms of the linear sensors 20X and 20Y. The waveform B is a waveform when only the signal when the light emission of the indicator 4 is turned on is read. The waveform of A is a waveform at the time of non-lighting, that is, a waveform of only disturbance light. In the ring CCD section 26 of the linear sensors 20X and 20Y described above with reference to FIG. 4, the charges of the pixels corresponding to the waveforms A and B are arranged adjacent to each other. Thus, the amplifier 29 actually obtains a difference value between the adjacent charge amounts, non-destructively amplifies the difference value, and outputs the result.

The output waveform of the amplifier 29 is a waveform of B-A, whereby the disturbance light component is canceled out, the noise is suppressed, and an image signal of only the blinking light from the indicator 4 can be obtained.

The PFAK shown in step S104 of FIG.
The value signal corresponds to the maximum value of the waveform of B-A. Since the signal is sequentially accumulated in the ring CCD unit 26 and becomes large by repetition of blinking, this level reaches a predetermined value TH1. , It is possible to always obtain an output waveform of a constant quality.

<Description of Coordinate Value Calculation> Next, the coordinate calculation unit 3
2 will be described with reference to FIG.

The output signals (difference signals from the amplifier 29) of the two linear sensors 20X and 20Y obtained as described above are n-bit (8-bit in this embodiment) provided in the sensor control unit 31. The AD converter 31A sends the digital signal to the coordinate calculator 32 as a digital signal to calculate the coordinate value. First, the coordinate values (X coordinates and Y coordinates) are calculated for the output data in each direction on the linear sensor.
1, Y1). The arithmetic processing is the same as X and Y, so only X will be described.

FIG. 10 shows a flow of a coordinate calculation process. In step S201, the process starts, and in step S202, difference data Dx
(1) to Dx (N) are read and stored in the buffer memory.

Next, in step S203, smoothing pre-filtering Dx2 (m) is performed in order to suppress noise and improve S / N. This is a very simple addition well known as the neighborhood operator (1,2,1).

Next, in step S204, the larger value of the maximum value and the pixels before and after the maximum value are searched, and the pixel numbers are set to nx and nx + 1.

Next, in step S205, the exact position between the peak pixels is determined as a type of differential operator (1,
1, 0, -1, -1). In this calculation, the zero cross of the differential waveform is obtained. However, by rearranging a simple equation, the equation has a very simple form shown in step 205.

Then, in step S206, the sum of the inter-pixel coordinate Gx thus obtained and the pixel number nx is obtained as the sensor output coordinate X1 of the X coordinate, and then the process ends in step S207.

<Explanation of the Overall Operation According to the Operation of the Pointing Tool> Next, the operation according to the present invention of the entire large display system of FIG.

When the operator presses the switch 43A of the pointing device 4, the light emitting element 41A emits light at a predetermined cycle, and an infrared light beam 45A is emitted. When the light beam 45A hits the screen 10 and the light spot 5 is irradiated, a part of the diffused light is detected by the light receiving element 6 and the light emitting element 41
A linear sensor 20 according to the predetermined light emission timing of A
X, 20Y are driven, and the diffused light is
It is detected at 20Y. Then, for example, the light spot 5 on the X axis and the Y axis with the origin at the center of the screen 10
Are calculated by the coordinate calculation unit 32 and output to the external connection device via the communication control unit 33.

After the processing by the external connection device, the cursor is displayed at the position of the light spot 5 on the screen 10 by the image signal processing unit 81 controlling the liquid crystal panel 82 in response to the image signal from the external connection device. You. 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.

From this state, when the operator presses the switch 43C, the state becomes a pen-down state, and screen control such as starting input of characters and line drawings and selecting and determining a button can be executed.

By pressing the switch 43D, the state of a pen button corresponding to a mouse button is established, and it is possible to correspond to another function such as a menu call. Thereby, the operator does not operate a keyboard or a mouse of an externally connected device such as a computer,
With only one hand holding the pointing tool 4, a character or figure can be drawn or a button or menu can be selected at an arbitrary position on the screen 10.

In the above operation, the linear sensor 20
The deviation of the squareness between X and 20Y, the detection error of the coordinate input device due to the output error of the linear sensors 20X and 20Y due to noise, the distortion of the projection optical system of the projection display device 8 such as the curvature of field, or the screen 10 The actual position of the light spot 5 of the light beam 45A deviates from the position of the detected light spot 5 due to the distortion of the display screen due to the assembling error of the light beam 45A. There is no concern about the deviation between the light spot 5 and the cursor or the locus displayed corresponding thereto, and an input operation with extremely high operability is realized.

In the above operation, if the operator is located at a position distant from the screen 10, the light beam 45 is emitted even if the tip of the pointing device 4 is intended to face the screen 10.
A comes off the screen 10 and the screen 1
There is a case where a cursor or the like corresponding to the light spot is not displayed on 0. The large-sized display system including the coordinate input device according to the present embodiment is used for a meeting in a conference room or the like, a video conference, or a so-called presentation as described above, and is used frequently by a specific operator at all times. Rather, the light beam 45A is used by an unspecified number of operators as needed, and the light beam 45A often comes off the screen 10 as described above. In addition, when the image displayed on the display screen is a complicated image, it is often difficult to find the position of the cursor or the like even if the light beam 45A hits the screen 10 and the cursor or the like is displayed. .

In such a case, the operator looks for the cursor while looking at the screen while changing the direction of the pointing tool 4, which is inconvenient.
If the cursor or the like cannot be found immediately or the cursor or the like cannot be moved, the operator checks whether the power switch (not shown) of the indicator 4 has been turned off.
Or is the battery of the indicator 4 running out?
Further, if there is concern that any device or system may have failed, the light beam 45A
May not act on the screen 10, but may take an action corresponding to this concern, resulting in extremely poor operability.

On the other hand, in this embodiment, when the cursor or the like is not displayed on the screen of the screen 10 as described above, or when it is difficult to find the cursor or the like even if it is displayed, the operator presses the switch 43B. , Light emitting element 4
1B is emitted, and a visible light beam 45B is emitted,
By irradiating the visible light spot 5 on the screen 10, the device housing near the screen 10, or the interior wall surface behind the screen 10, the indicated position of the indicating tool 4 can be immediately found. In this case, the light emitting element 4
Either 1B may emit light, or both the light emitting elements 41A and 41B may emit light. Also, the light emitting element 41
The light emission of B may be continuous or blink at a predetermined cycle. Further, when the switch 43B is pressed once, the light emitting element 41B may emit light for a predetermined time. In any case, if the operator can recognize the light spot 5, the object can be achieved.

As described above, the light spot is on the screen 1
When the position is outside the range of 0, or when the position of the cursor or the like cannot be found even on the screen 10, the position indicated by the coordinate pointing tool can be immediately identified by using a visible light spot, and good operation can be performed. Can be realized.

Further, in a configuration in which only the visible light is emitted when the switch 43B is pressed, it can be used as a so-called pointer. For this reason, the operator can
Move the cursor on the screen, select a menu or icon, or draw a locus, and simply point the screen at the visible light spot as a pointer,
Various explanations can be made with the same pointing tool, and extremely efficient meetings and presentations can be performed.

<Other Embodiments> In the above embodiment, the coordinate detector 1 and the pointing device 4 transmit signals from the pointing device 4 to the coordinate detector 1 by passing signals in only one direction. However, as shown in FIG. 11 as another embodiment,
The coordinate detector 1 and the pointing device 4 may be connected by a cable 11 and a signal may be transmitted from the coordinate detector 1 to the pointing device 4 to perform bidirectional communication. Alternatively, two-way wireless communication may be performed by using a configuration in which the coordinate detector 1 has a light emitting unit and the pointing device 4 has a light receiving unit, like an infrared remote controller that is widely and generally used.

In this case, if the infrared light beam 45A of the pointing device 4 does not hit the screen 10 and the light receiving element 6 does not detect the diffused light of the infrared light spot 5,
It is assumed that a signal instructing light emission of the visible light emitting element 41B is transmitted from the coordinate detector 1 to the indicator 4 via the cable 11 or the wireless communication means. Then, in response to this signal, the light emission control unit 44 sets the visible light emitting element 41
B automatically emits light.

Thus, while the operator presses the switch 43A to emit the infrared light beam 45A,
Even if the direction of the pointing device 4 is directed to the outside of the screen 10, the visible light beam 45B is automatically emitted without pressing the switch 43B, and the pointing position of the pointing device 4 can be immediately known, and good operability is obtained. Can be realized.

In the above case, the light emission of the light emitting element 41B is similar to that of the previous embodiment.
Only the light emitting element 41A and the light emitting element 41B may emit light. In addition, the light emission of the light emitting element 41B may be blinked continuously or at a predetermined cycle.

Further, in this embodiment, since the signals by operating the switches 43A, 43B, 43C and 43D of the pointing device 4 can be transmitted to the coordinate detector 1 via the cable 11, for example, the light received by the coordinate detector 1 A configuration in which the element 6 is eliminated is also possible. In this case, it is assumed that a synchronization signal of light emission and light reception is transmitted from the coordinate detector 1 to the indicator 4 via the cable 11, and the light emission of the light emitting elements 41A and 41B is controlled by the synchronization signal. It is assumed that the presence or absence of the irradiation of the infrared light beam 45A of the pointing tool 4 on the screen 10 is detected by the linear sensors 20X and 20Y.

In the embodiment described above, a configuration using a linear sensor is used. However, it goes without saying that an area sensor or a PSD may be used. Further, it goes without saying that any image processing such as using barycentric coordinates or pattern matching may be performed in calculating the coordinate values. Further, the projection type display device 8 is of the rear type, but needless to say, may be of the front type.

[0084]

As is apparent from the above description, according to the present invention, an arbitrary position on the coordinate input surface of the optical coordinate input device is designated to irradiate a light spot to input coordinates. In the coordinate input indicator, visible light and invisible light can be selectively emitted for irradiating a light spot, and visible light and invisible light can be selectively used as needed. For example, when the coordinate input device is used in a display system using a coordinate input surface as a display screen, and the light spot is located within the display screen (coordinate input surface), the light spot is formed by using invisible light, Correspondence with a cursor, a locus, or the like displayed on the display screen correspondingly does not matter at all. When the light spot is outside the display screen, or when the cursor or the like displayed corresponding to the light spot cannot be found even within the display screen, the visible light is used to promptly operate the coordinate input indicator. The indicated position is known. In this way, an excellent effect that the operability and usability of the coordinate input pointing device can be improved can be obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a coordinate input indicator and a coordinate detector according to an embodiment of the present invention.

FIG. 2 is a block diagram showing an entire configuration of a large display system including the coordinate input device according to the embodiment.

FIG. 3 is a perspective view showing an arrangement relationship of a linear sensor of the coordinate detector in the embodiment.

FIG. 4 is a block diagram showing an internal configuration of the linear sensor.

FIG. 5 is a side view showing the appearance of the coordinate input pointing device of the embodiment.

FIG. 6 is a timing chart of signal waveforms for explaining an operation of restoring a control signal from an output signal of a light receiving element in the coordinate detector of the embodiment.

FIG. 7 is a timing chart at the end of a series of operations for restoring a control signal from an output signal of the light receiving element.

FIG. 8 is a flowchart showing a control operation of the linear sensor in the embodiment.

FIG. 9 is a waveform chart showing an example of an output waveform of the linear sensor.

FIG. 10 is a flowchart showing a coordinate calculation process in the embodiment.

FIG. 11 is a block diagram illustrating a configuration of a coordinate input indicator and a coordinate detector according to another embodiment.

[Explanation of symbols]

 Reference Signs List 1 coordinate detector 2 coordinate detection sensor unit 3 controller 4 coordinate input indicator 5 light spot 6 light receiving element 7 signal processing unit 8 projection display device 10 screen 11 cable 20X, 20Y linear sensor 31 sensor control unit 32 coordinate calculation unit 41A 41B Light emitting element 42A, 42B Light emission drive unit 43A to 43D Operation switch 44 Light emission control unit 45A Infrared light beam 45B Visible light light beam 71 Frequency detection unit 72 Control signal detection unit

Continued on the front page (72) Inventor Jun Tanaka 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Yuichiro Yoshimura 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Katsuyuki Kobayashi 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Isamu 3-30-2 Shimomaruko 3-chome, Ota-ku, Tokyo Canon Inc. (72) Invention Person Masaaki Kinpu 3-30-2 Shimomaruko, Ota-ku, Tokyo F-term in Canon Inc. (reference) 5B068 AA05 BB18 BC03 BD02 BD09 BD21 CC18 CD05 5B087 AA09 BC03 BC16 BC32 CC09 DD10 DE07

Claims (3)

[Claims] 1. A coordinate input pointing device for inputting coordinates by irradiating a light spot by designating an arbitrary position on a coordinate input surface of an optical coordinate input device, comprising: A first light emitting means for emitting light, and a second light emitting means for emitting invisible light for irradiating the light spot
A light emission control means for selectively emitting light from the first light emission means and the second light emission means. 2. The coordinate input pointing device according to claim 1, wherein the invisible light is infrared light. 3. The coordinate input device according to claim 1, wherein said light emission control means selectively emits light from said first light emission means and said second light emission means in response to an operation of a manual switch. Pointer.