JPH0354616A - Electromagnetic induction tablet - Google Patents

Abstract

PURPOSE:To reduce full scan as far as possible and to increase read speed at that rate by reading the indicated position of a position indicator by performing the full scan of a driving line group and a sense line group when a first read operation is performed and performing a following speed operation based on the position. CONSTITUTION:An initial read operation, and a current read operation which defines a small area including the indicated position read based on the initial read operation and reads the indicated position of the position indicator 6 by operating the driving line group 1 and the sense line group 2 in the area are provided. Extension read operation which extends the small area defined when no prescribed voltage signal is induced in the current read operation and re- defines the area so as to extend gradually, and operates the driving line group 1 and the sense line group 2 in an extension area and reads the indicated position of the position indicator 6 is provided, and a processing circuit 51 which executes whose operations corresponding to a prescribed program is provided. In such a way, overall read speed can be increased by reducing the operations of all the driving lines and sense lines, respectively as far as possible.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an electromagnetic induction tablet, and in particular,
The present invention relates to an electromagnetic induction tablay in which a large number of grid conductors are selectively switched and connected.

[Conventional technology]

Figure 2 shows the patent application filed earlier by the applicant in 1983-19.
FIG. 6 is a front view showing the structure of the device described in No. 6 2 5 2.

This device consists of a drive line group 1 consisting of a large number of folded grid conductors disposed on a reading surface, a sense line group 2 consisting of a large number of folded grid conductors disposed orthogonally to the drive line group 1, and a sense line group 2 consisting of a large number of folded grid conductors arranged perpendicular to the drive line group 1. It has a position indicator 6 which is positioned on the reading surface and gradually indicates power coordinates.

Each of the drive lines in the drive line group I is sequentially selected by the drive line scanner 3 and supplied with a predetermined alternating current. During the period when a predetermined alternating current is being supplied to each drive line, the sense line scanner 4 operates and sequentially switches and connects each sense line of the sense line group 2, and the sense lines are guided to the sense lines. Obtain the voltage signal.

For example, if the position indicator 6 is connected to the drive line 1 (
i), drive lines 1 (i-1), 1 (i), 1 (i+1)
When alternating current is supplied to each of the coils 61 of the position indicator 6, a predetermined voltage is induced in the coil 61 of the position indicator 6.
An alternating magnetic field is generated from the This AC magnetic field acts on the sense line group 2 and induces a predetermined voltage to the sense lines in the vicinity thereof. Assume that an alternating current is now being supplied to the drive line 1(i). The sense line scanner 4 sequentially switches and connects the sense line group 2 during this period to acquire the voltage signal induced in each sense line. In the example shown in FIG. 2, the sense lines 2 (i), 2 (i+1), 2 (i
+2), a predetermined voltage signal is obtained. This voltage signal is input to the processing circuit 51 and the coordinate position is determined.

[Problem that the invention seeks to solve]

By the way, in a normal device of this kind, for example, the second
By acquiring the above-mentioned data regarding the area (symbol A) surrounded by the dashed line in the figure, it is possible to accurately and gradually determine the position indicated by the position indicator 6. This can be done by increasing the reading speed by using some method to gradually change the indicated position of the position indicator 6 so that the data acquisition operation is performed only for the small area A as shown in FIG. be able to.

The present invention has been made with the object of improving the overall reading speed by minimizing the number of operations of all drive lines or all sense lines.

[Means for solving problems]

For this reason, the present invention includes an initial reading operation in which the drive line group and the sense line group are operated over the entire area during the first reading operation, and the first indicated position of the position indicator is gradually read. A small area including the indicated position read based on is defined, and the drive line group and sense line group in this area are operated to gradually read the defined small area, and during this current reading operation, a processing circuit that operates a drive line group and a sense line group in the defined enlarged area to gradually enlarge and read the defined small area, and executes each of these operations according to a predetermined program; It is set up.

It is set up.

[Effect]

During the first read operation, the driving line group and the sense line group are scanned over the entire surface, a defined small area is read, and a subsequent read operation is performed based on this read position. Therefore, compared to conventional devices, the number of full-plane scans can be minimized, and the reading speed can be increased accordingly.

〔Example〕

FIG. 1 is a schematic diagram for explaining the reading operation of the apparatus according to the present invention. The configuration of the present invention can be realized by having the configuration shown in FIG. 2 hold a predetermined operation program.

Hereinafter, with reference to FIGS. 1 and 2, 1 of the operations of the apparatus of the present invention will be explained.
Explain an example.

(1) First, let us consider, for example, when the electromagnetic induction tablet shown in FIG. 2 is powered on and starts position reading.

The drive line scanner 3 shown in FIG. 2 is controlled by a processing circuit 51 to select, for example, every other drive line and supply a predetermined alternating current. While alternating current is being supplied to each drive line, under the control of the processing circuit 51, the sense line scanner 4 selectively connects, for example, every other sense line to detect whether or not a voltage signal is induced. .

By sequentially performing such scanning over the entire reading surface, the approximate shield position where the position indicator 6 is present can be determined. In this way, it is recognized that the position indicator 6 is positioned near the intersection of the drive line Hi) and the sense line 2 (i+1).

(2) Next, the processing circuit 51 of the device shown in FIG. 2 defines a small area including the approximate position of the position indicator 6 determined in (2) above, according to the operation program. This small area includes at least three drive lines 1 (i-1), 1 (i), 1 (i+1) and sense lines 2 (iL2 (i+1), 2 ( i+2)
is defined to include.

(2) When this definition is completed, the drive line scanner 3 and the sense line scanner 4 respectively scan the drive lines and sense lines in the small area under the control of the processing circuit 5l.

First, the drive line scanner 3 is connected to the drive line 1 (i-1) and supplies a predetermined alternating current. While this alternating current is being supplied, the sense line scanner 4 detects the sense line 2 (i
), 2 (i+1), and 2 (i+2) to obtain a voltage signal, which is then sent to the processing circuit 5 via the sense circuit 54.
1 is temporarily stored in a memory (not shown). Next, the drive line scanner 3 connects to the drive line 1(i) and supplies alternating current to this drive line for a predetermined period of time. Also at this stage, the sense line scanner 4 scans the sense lines 2(i) and 2(i+1).
, 2(i+2) to obtain a voltage signal and store it in a memory (not shown) of the processing circuit 51. Similarly,
Sense line 2 (i), 2 for drive line 1 (i+1)
The acquired data of (i+1) and 2 (i+2) are also stored in the memory of the processing circuit 51.

These data are held in the processing circuit 52 as follows.

Sense line 2 (i) 2 (i+1) 2 (i+2) Hi-1) Di D2 D3 drive 1 (i) D4 D5 D6 line 1 (i+1) D7 D8 D9 The processing circuit 51 processes data D2, D5 and 2nd from D8
The positions in the vertical axis direction of the figure are calculated, D4, D5 and D6
From this, the position in the horizontal axis direction in FIG. The absolute position of is determined. In this way, according to this method, the coordinate position can be determined by obtaining data of five points.

■ The above operation (■) is repeatedly performed in a loop. Now, let us consider a case where the operator specifies another position and this specified position is located ζ outside the small area. In this case, even if the same operation as above (2) is performed, a voltage signal exceeding a predetermined level will not be induced in the sense line group, so the processing circuit 51 will be able to detect the position indicator 6 within this small area. I know it doesn't exist.

Processing circuit 51 defines a new area. This area is
The new area is set to be expanded based on the reading position immediately before the state in which the new area is to be defined. This work will be completed after some expansion.

In this case, as shown in FIG. 1, the area creation method is to select, for example, two reading positions (P2) immediately before the temporarily enlarged areas (codes B and C) are created.
, P3). In addition, in this figure, the position is read in one step of P1, P2, and P3, and the next designated position to be gradually designated is P4.
The case where the image is expanded to area C is shown.

Further, in this case, if the temporarily enlarged area is enlarged beyond a predetermined area, the operation described in (2) is performed again.

Furthermore, as an operation different from the above-mentioned operation, the position indicator 6
When performing the position determining operation, the general position determining operation and the precise position determining operation of the position indicator 6 can be configured to be performed without fail. For example, when the position indicator 6 is located outside the small area, an area is defined that is expanded to a certain extent, and for scanning in that area, both the drive line group and the sense line group are set, for example, every other line. A scanning operation is performed, and the precise position determination operation shown in (3) above is performed based on the obtained approximate position.

FIG. 3 is a flowchart of the above position determination operation.

〔Effect of the invention〕

As described above, according to the present invention, the scanning operation of scanning the entire area of the tablet can be minimized, so that the position reading operation can be improved overall.

[Brief explanation of drawings]

1 to 3 are explanatory diagrams showing embodiments of the present invention, and FIG. 1 is a schematic diagram showing an example of the reading operation of the device of the present invention,
FIG. 2 is a front view showing an embodiment of the device of the present invention and the general structure of this type of electromagnetic induction tablet, and FIG. 3 is a flowchart showing the operation of the device of the present invention. I.1 Drive line group 2- Sense line group 51 --- Processing circuit

Claims (1)

[Scope of Claims] A drive line group in which a large number of drive lines are arranged in a first direction; a sense line group in which a large number of sense lines are arranged in a second direction perpendicular to the first direction; a drive line scanner that selectively connects to a large number of drive lines in the drive line group to supply alternating current; a position indicator that generates an operating magnetic field by the action of the alternating current flowing through the drive lines; a sense line scanner that is selectively connected to the sense line to obtain a voltage signal induced by the action magnetic field of the position indicator of the sense line; and a sense line scanner that receives the voltage signal from the sense line scanner and determines the indicated position of the position indicator. and a processing circuit configured to determine and control said means, said processing circuit controlling said drive line group and said sense line group over their entire area during a first reading operation. Define an initial read operation to read the first indicated position of the position indicator, define a small area including the indicated position read based on this initial read operation, and define the drive line group and sense line group within this area. and a current reading operation of scanning and reading the indicated position of the position indicator, and gradually expanding the defined small area when a predetermined voltage signal is not induced in the sense line group during this current reading operation. and an enlarged reading operation in which the driving line group and the sense line group in the enlarged area are redefined to read the indicated position of the position indicator, and each of these operations is executed according to a predetermined program. An electromagnetic induction tablet.