JPH07302152A - Coordinate detecting method for coordinate input device - Google Patents

Abstract

PURPOSE:To provide a coordinate detecting device of a coordinate input device which can increase the moving speed of an input pointing device and also can improve the working efficiency. CONSTITUTION:In reference to the coordinate input method of a coordinate input device, the maximum voltage induced at the tablet side by a magnetic field generated by an input pointing device is calculated together with a detection loop that shows the maximum induced voltage value. Then the maximum induced voltage value is compared with the induced voltage value of the detection loop formed at one of both sides adjacent to the detection loop showing the maximum induced voltage value. If no difference is confirmed through the comparison and the relation is reversed between both induced voltage value compared with each other and the induced voltage value of the detection loop of the other side adjacent to the detection loop showing the maximum induced voltage value, the coordinates of the pointing device are decided based on both induced voltage value compared with each other and the induced voltage value of the detection loop following the compared one.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coordinate detecting method for an electromagnetic induction type coordinate input device.

[0002]

2. Description of the Related Art A conventional technique will be described with reference to FIGS.
◆ FIG. 4A schematically shows the configuration of an electromagnetic induction type coordinate input device. In the figure, 1 to 7 are detection loops, which are wired on the tablet 8 at equal intervals. Reference numeral 9 is an input indicator having an excitation circuit. 10 is an induced voltage measuring unit. 11
Is a control unit that performs storage and comparison operations. Then, when the input indicator 9 is placed on the tablet 8, the detection loops 1 to 7 are generated by the magnetic field formed by the excitation circuit of the input indicator 9.
The induced voltage generated in the
Find the coordinates of. Hereinafter, the input indicator 9 is used as the detection loop 4
In the above case, the coordinate detection procedure will be further described with reference to FIG. 5 showing the flowchart of the whole scan process and FIG. 6 showing the flowchart of the follow-up scan process. When the input indicator 9 is placed in the detection loop 4, an induced voltage as shown in FIG. 4B is generated in the detection loops 1 to 7. Here, the number of data used for performing the above-mentioned comparison calculation processing is three, and the detection loop which generates the maximum induced voltage, that is, the detection loop 4 closest to the input indicator 9 is used.
And the value of the induced voltage of the detection loops 3 and 5 located on both sides of the induced voltage. Therefore, first, the entire scan, that is, the detection loop 1 to the detection loop 7 is scanned (S
100), and the presence or absence of induced voltage is confirmed (S110). When the induced voltage is generated, the number n (n = 4 in this case) of the detection loop n (hereinafter referred to as the detection center loop n) having the maximum induced voltage is stored in the memory A of the control unit 11. (S120) and shifts to the follow-up scan. ◆
In the following scan, first, the induced voltage value VA _n of the detection center loop n is stored in the memory C (S200). Subsequently, the induced voltage value VA _n-1 of the detection loop n- ₁ is stored in the memory D,
The induced voltage value VA _{n + 1} of the detection loop n + 1 is stored in the memory E (S210, S220), and the values of the memory C and the memory D are compared (S230). Then, if VA _n > VA _n−1 , the voltage values of the memory C and the memory E are continuously compared (S240), and if VA _n > VA _{n + 1} , the coordinate value is calculated by the comparison calculation process ( S250) and returns to S200.
◆ If VA _n ≤VA _n-1 in S230, _n-1 of the detection center loop n-1 is set as n again in the memory A.
(S260) and returns to S200. In addition, S24
If VA _n ≦ VA _{n + 1} at 0, the detection center loop n
+1 is again stored in the memory A as n (S270),
Return to S200. ◆ The induced voltage value VA _n detection center loop n, an accurate coordinate values from three data of the induced voltage value VA n _{+ 1} of the induced voltage in the detection loop n-1 value VA _n-1 and the detection loop n + 1 decide.

[0003]

However, if the input indicator is moved fast, the follow-up scan continues to be repeated and three pieces of data cannot be determined. Therefore, it is necessary to set a limit on the moving speed of the input indicator. there were. An object of the present invention is to solve the above-mentioned problems, and to provide a coordinate detection method for a coordinate input device that can increase the moving speed of the input indicator and improve work efficiency.

[0004]

Means for Solving the Problems The above-mentioned problems are caused by the maximum induced voltage value of the induced voltage values induced on the tablet side by the magnetic field formed by the input indicator and both sides of the detection loop having the maximum induced voltage value. In the coordinate detection method of the coordinate input device that determines the coordinates of the input indicator from the induced voltage value of the detection loop located at, first find the maximum induced voltage value and the detection loop that becomes the maximum induced voltage value, and then Compare the magnitude relationship between the induced voltage value and the induced voltage value of the detection loop on one side located next to the detection loop that becomes the maximum induced voltage value,
When the magnitude relationship does not change, from the two induced voltage values compared with the induced voltage value of the detection loop on the other side located next to the detection loop having the maximum induced voltage value, when the magnitude relationship is reversed, This is solved by determining the coordinates of the input indicator from the two induced voltage values compared and the induced voltage value of the next detection loop on the side of the detected loop compared.

[0005]

The data to be newly detected may be a single data whose detection loop number is uniquely determined, and since the state of repeating the follow-up scan does not continue, the detection time can be shortened.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A case in which an input indicator 9 is in a detection loop 4 as in the case of the above-mentioned conventional technique will be described below as an example with reference to FIG. 1 showing a follow-up scan of the present invention.
The configuration of the coordinate input device is substantially the same as that of the conventional coordinate input device described above, and the flowchart of the whole scan is the same as that of the conventional coordinate input device described above. Then, it is assumed that the number 4 of the detection center loop n is stored in the memory A by the whole scan. ◆
First, the induced voltage value VA _n of the detection center loop _n is stored in the memory C
(S300), and subsequently, the induced voltage value VA _n-1 of the detection loop n-1 is stored in the memory D (S310).
Then, the values of the memory C and the memory D are compared (S32
0). Here, if VA _n > VA _n−1 , the detection center loop n has not changed, and therefore the detection loop n +
The induced voltage value VA _{n + 1} of ₁ is stored in the memory E (S33).
0). Then, the voltage values of the memory C and the memory E are compared (S340), and if VA _n > VA _{n + 1} , the coordinate value is calculated by the comparison calculation process (S350), and the process returns to S300. ◆ If VA _n ≤VA _n-1 in S320, n-1 is stored again in the memory A as n (S36).
0). In this case, the input indicator 9 moves in the direction shown in FIG. 2A, and the induced voltage value is generated as shown in FIG. Therefore, the contents of the memory C are moved to the memory E (S370), and then the contents of the memory D are moved to the memory C (S380). Then, the induced voltage value VA _n-1 of the detection center loop n−1, that is, VA ₂ is newly stored in the memory D (S390), and the coordinate value is calculated (S350).
Return to S300. ◆ Again, VA in S340
_{If n} ≦ VA _{n + 1} , n + 1 is stored again in the memory A as n (S400). In this case, the input indicator 9 moves in the direction shown in FIG. 3A, and the induced voltage value is shown in FIG.
Is happening like. Therefore, the contents of the memory C are moved to the memory D (S410), and then the contents of the memory E are moved to the memory C (S420). Then, a new induced voltage value VA _{n + 1} of the detection center loop n + 1, that is, V
A ₆ is stored in the memory E (S430), the coordinate value is calculated (S350), and the process returns to S300. ◆

[0007]

As described above, according to the present invention,
First, find the maximum induced voltage value and the detection loop that gives the maximum induced voltage value, and then find the maximum induced voltage value and the induced voltage value of the detection loop on one side that is located next to the detection loop that gives the maximum induced voltage value. The magnitude relationship is compared, and when the magnitude relationship does not change, the magnitude relationship is determined from the two induced voltage values compared and the induced voltage value of the detection loop on the other side located next to the detection loop with the maximum induced voltage value. When reversing, the coordinate of the input indicator is determined from the two induced voltage values compared and the induced voltage value of the next detection loop on the side of the detected loop that is compared. Just enough.
◆ As a result, the detection time is shortened, and the input indicator can be moved in a short time, so that the working efficiency can be improved.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of the present invention.

FIG. 2 is a level of an induced voltage induced when an input indicator moves to a detection loop 3.

FIG. 3 is a level of an induced voltage induced when the input indicator moves to the detection loop 5.

FIG. 4 is a level of an induced voltage induced when the input indicator is in the detection loop 4.

FIG. 5 is a flowchart of a whole scan.

FIG. 6 is a diagram illustrating a conventional technique.

[Explanation of symbols]

 1 to 7 detection loop 8 tablet 9 indicator for input 10 induced voltage measurement unit 11 control unit

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoshihisa Osaka 2100 Kamiimaizumi, Ebina, Kanagawa Hitachi Seiko Co., Ltd.

Claims (1)

[Claims] 1. A maximum induced voltage value among induced voltage values induced on a tablet side by a magnetic field formed by an input indicator and an induced voltage value of detection loops located on both sides of the detection loop having the maximum induced voltage value. In the coordinate detection method of the coordinate input device for determining the coordinates of the input indicator from and, first obtain the maximum induced voltage value and the detection loop that becomes the maximum induced voltage value,
Next, the magnitude relationship between the maximum induced voltage value and the induced voltage value of the detection loop on one side located next to the detection loop with the maximum induced voltage value is compared, and if the magnitude relationship does not change, the two induced comparisons are compared. When the magnitude relationship is reversed from the voltage value and the induced voltage value of the detection loop on the other side located next to the detection loop that is the maximum induced voltage value, the detected value compared with the two induced voltage values compared A coordinate detecting method for a coordinate input device, wherein the coordinate of the input indicator is determined from the induced voltage value of the next detection loop on the loop side.