JPH01113823A - Touch panel type keyboard - Google Patents

Abstract

PURPOSE:To prevent misdecision by deciding a key input when both the contact time for key input and the contact area exceed each reference level. CONSTITUTION:When the number of detecting points (contact area) are counted by a counter 7, the output (high level) of a comparator 5 is supplied to an AND gate 8 together with a time clock S2 for measurement of time. This clock S2 itself is delivered from the output of the gate 8 and the finger touch time is counted by a counter 9. The values of both counters 7 and 9 are compared with each reference level by comparators 10 and 11 respectively. Then high levels are delivered from counters 7 and 9 when their count values exceed each reference level. Under such conditions, the outputs of both comparators 10 and 11 are set at high levels. At the same time, a high level is also outputted from an AND gate 12. Thus judged that a key is inputted and also discriminated from a misinput.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a touch panel keyboard such as an input device.

(Prior technology) In order to prevent erroneous inputs caused by momentarily touching the keyboard panel with a finger or the like when the user does not intend to input, a conventional process for touch panel keyboards is that the panel is not considered to be input unless the panel is touched for a certain period of time. It had become.

However, this process has a problem in that if a part of the fingertip or the like touches the object for a certain period of time or more, it is considered an input, and erroneous input cannot be completely prevented.

(Problems to be Solved by the Invention) Conventional touch panel keyboards have a problem in that touching the keyboard for a certain period of time is considered an input, and erroneous input cannot be completely prevented.

Therefore, an object of the present invention is to eliminate this problem and provide a keyboard panel that does not cause erroneous judgments.

[Structure of the Invention] (Means for Solving the Problems) The touch panel type keyboard of the present invention includes means for detecting the ratio of the contact area of a contact object to the key input area and the contact time, and detecting the area, The object is quickly accomplished by providing a means for determining whether the time and time exceed a certain reference value and determining that a key input has been made only when both conditions are satisfied.

(Function) In the present invention, the ratio of the contact area of the contact object to the key input area and the contact time are detected using a pair of scanning lines and reception lines that subdivide the key input area, and the area and time are determined as respective standards. When the value is greater than or equal to the value, it is determined that the input is a key input, thereby distinguishing it from an erroneous input.

(Example) Next, this embodiment will be described with reference to the drawings.

1, 2, and 3 show an embodiment of the device according to the present invention. In FIG. 1, 1 is a capacitive touch panel for input, and this touch panel 1 is transparent. It is assumed that a key input area is displayed below. 2
3 is a scanning line for detecting a contact position of a finger or the like, and 3 is a receiving line for detecting a change in voltage. FIG. 2 is an enlarged view of a part of the touch panel 1, and 4 is a key input area (the area surrounded by a thick line is the input area for one key). Figure 3 shows a circuit that counts the contact time and the number of detection points, and 5 is the detection voltage VD output from the receiving line 3.
A comparator that becomes IIGH level when there is a difference between the voltage and the reference voltage ■s. 6 is an AN that outputs a pulse of shift clock S1 only when a difference is detected by comparator 5.
D gate 7 is a counter for counting the number of pulses output from AND gate 6. 8 is an AND gate for outputting a timer clock S2 for measuring time only when a difference is detected by the comparator 5 (a finger or the like is in contact). 9 is determined by the output signal of AND gate 8,
This is a counter to actually measure the contact time. io
, il is a comparator for comparing whether the outputs of the counters 7 and 9 are each higher than the reference value. 1
2 is HIGH only when the contact area and contact time satisfy the conditions by the output signals of comparators 10 and 11.
This is an AND gate for outputting a level.

Next, the present invention will be explained in detail.

Detection of the touch position on the touch panel is performed as follows. First, voltage is applied to the scanning lines 2 built into the touch panel in order from one end to the other. At this time, a certain voltage is detected from the receiving line 3 paired with the scanning line 2. The scan line 2
When the finger is in contact with the receiving line 3, the capacity I between the two lines is
This is different from the capacitance C2 when C1 is not in contact. Therefore, the detected voltage V is expressed as [C1/(Co+C1)] V□ (V□ is the voltage applied to the scanning line 2), assuming that the capacitance between the reception line 3 and GND is co (always constant). It will be done. On the other hand, the voltage vs detected when the finger is not in contact is [C2/(C□ +
02)] is given by V□ and is always constant, and this voltage is used as the reference voltage. Therefore, the detection voltage V0 is the standard voltage V
By comparing , with the comparator 5, it is possible to detect whether or not the finger is in contact, and its position can be determined by whether the finger is detected at the lock position of the shift clock S1 for scanning the scanning line 2.

Next, when there is a difference between the detection voltage ■ and the reference voltage V, the comparator 5 outputs a HIGH level, and by ANDing it with the shift clock S1,
The AND gate 6 outputs the shift clock S1 itself. On the other hand, if there is no difference, the comparator 5 outputs a LOW level, and the output of the AND gate 6 is fixed at the LOW level. Therefore, counter 7
Now, the number of detection points (contact area) will be counted.

At this time, the output of the comparator 5 (H
IGH level) and the time clock S2 for time measurement are input, so the output of the AND gate 8 is the time clock S? for time measurement. The output is output, and the time that a finger or the like is in contact with it is measured by a counter 9. The value of the counter 7.9 is compared with each reference value by comparators io and 1i, and if the value exceeds the reference value, a HIGH level is output from the comparator 10°'11. And when both are above the standard value, 10 and 1
1 becomes HIGH level, AND gate 12 also outputs HIGH level, and it can be determined that a key input has been made.

[Effects of the Invention] As explained above, when both the contact time and contact area for key input exceed respective reference values, it is determined as a key input, thereby preventing erroneous determination. - Qi 2 Qi 1

[Brief explanation of the drawing]

FIG. 1 is an external view of a touch panel showing an embodiment of the touch panel type keyboard of the present invention, FIG. 2 is a diagram of its key input area, and FIG. 3 is a block diagram of a counting circuit. 1...Touch panel 2...Scanning line 3...Receiving line 4...Key input area'l in 11.
...] Lupa I number (3, 7, 12...AND gate V□...detection voltage V3...Pawn voltage S1.S2
... Clock Pulse Agent Patent Attorney Nori Chika Yuki Sanno - Figure 2

Claims (1)

[Claims] In a touch panel keyboard, there is a means for detecting the ratio of the contact area of a contact object to the key input area and the contact time, and this means determines whether or not both the area and the time exceed a certain reference value, and the method determines whether both the area and the time exceed a certain standard value. A touch panel type keyboard characterized by comprising means for determining that a key input has been made only when the following conditions are satisfied.