JP3170991B2 - Angle control method for optical touch panel - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical touch panel comprising a light emitting element on two sides adjacent to a rectangular display screen of an image display means and a plurality of light receiving elements on the other two sides. Further, the present invention relates to an angle control method for an optical touch panel that variably controls the angle of a display screen.

[0002]

2. Description of the Related Art Conventionally, there are optical touch panels described in Japanese Utility Model Laid-Open No. 63-31439 and Japanese Utility Model Laid-Open No. 3-103536. It has a configuration.

That is, a plurality of light emitting elements 3 are arranged on each side of a rectangular display screen 2 of an image display means 1 comprising a liquid crystal display (hereinafter referred to as LCD) housed in a case (not shown). An element array is formed, a plurality of light receiving elements 4 are arranged on each of the remaining vertical and horizontal sides to form a light receiving element array, and a matrix-like optical path is formed between the opposing light emitting and light receiving elements 3 and 4. By touching the display screen 2 with the finger 5, the path of light from each light emitting element 3 to the light receiving element 4 at the opposing position is blocked, and the blocked light emission,
The position of the set of the light receiving elements 3 and 4 is derived, and the coordinates of the position touched by the finger 5 on the display screen 2 are calculated.

When this type of optical touch panel is applied to, for example, a car navigation system, the environment is susceptible to disturbance light, and the disturbance light enters the light receiving element 4 and emits light from the light emitting element 3. Is not accepted, and even if the driver blocks light from the light emitting element 3 with the finger 5, light (disturbance light) constantly enters the light receiving element 4, and the coordinates on the display screen 2 touched by the finger 5 are displayed. When the conventional optical touch panel is used in an environment that is susceptible to disturbance light, it is conceivable to prevent the influence of disturbance light as shown in FIG. Have been.

Since the light from the light emitting element 3 is normally a pulse light, if the light receiving element 4 receives the pulse light, the output signal has a pulse waveform. Since the waveform of the output signal of the light receiving element 4 shows a substantially constant level when the disturbance light having a higher level than the peak level is received, the high level of the disturbance light is received by monitoring the output signal of the light receiving element 4. 8, the light emitting element 3 can be detected based on the output signal of the light receiving element 4 as shown in FIG.
It is determined whether or not it is in a state of receiving disturbance light having a higher level than the pulse light from (step S1), and if the determination result is YES, the switch function of the touch panel is canceled (step S2), and the determination result Is NO, the light emitting elements 3 are sequentially driven (step S3), and after the output signal of the light receiving element 4 facing each light emitting element 3 is detected (step S4), all the light emitting and light receiving elements 3 , 4
It is determined whether or not the driving and detection have been completed (step S5). If this determination is NO, the process returns to step S1, and if the determination is YES, step S6 is performed.
Then, the coordinates of the position touched by the finger 5 on the display screen 2 are calculated based on the output signal of each light receiving element 4 (step S6), and the operation ends after the processing of step S2.

[0006]

However, in this case, once the switch function of the touch panel is canceled, the vehicle or the like must be moved until the influence of disturbance light disappears, which is very troublesome. .

On the other hand, in order to eliminate the inconvenience as described above, for example, as described in JP-A-64-44180 and Japanese Utility Model Laid-Open Publication No. 5-74996, an eaves for disturbing light is provided near the display. It is considered that such an eaves is provided. However, if the eaves is provided in this way, in the case of an automobile, the design of the interior of the vehicle may be damaged, and furthermore, there is a fear that the switch operation of other electronic devices may be hindered.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has as its object to eliminate the influence of disturbance light without providing a conventional eave or the like.

[0009]

According to the first aspect of the present invention,
A case accommodates image display means, and a plurality of light emitting elements are arranged around two adjacent sides of a rectangular display screen exposed at the opening of the case to form a light emitting element row, and the remaining two sides are formed. A plurality of light receiving elements that receive light from each of the light emitting elements are arranged in the periphery to form a light receiving element row, and a matrix light path is formed between each of the light emitting elements and each of the light receiving elements. An optical touch panel for detecting a blocking position when the optical path is blocked by a blocking object such as a finger, wherein each of the ends of the image display means is rotatable in the front-rear direction on the case. A display means is attached, and a rotation means for rotating each end of the image display means in the front-rear direction is provided, and each light receiving element is separated from each light emitting element by the influence of disturbance light based on an output signal of each light receiving element. The light of The control means detects whether or not the light can not be received, and controls the driving means for driving the rotating means by the control means when each of the light receiving elements is under the influence of disturbance light. Is characterized in that the rotating means is driven so that a predetermined end of the image display means is rotated so as not to be affected by disturbance light, and the angle of the display screen is variably controlled.

According to a second aspect of the present invention, the output signal of each of the light receiving elements is monitored while each end of the image display means is sequentially rotated by the rotating means, and each of the light receiving elements is disturbed. It is determined whether or not the light receiving element is not affected by light, and the respective light receiving elements are not affected by disturbance light while the end of the image display means is rotated to a predetermined angle by the rotating means. If not, the rotation means rotates the next end of the image display means, and while the rotation means rotates the end of the image display means to a predetermined angle, each of the light receiving elements When it is determined that the image display means is not affected by disturbance light, the rotation of the end of the image display means by the rotation means may be stopped.

[0011]

According to the present invention, the control means detects whether or not each light receiving element cannot receive light from each light emitting element due to the influence of disturbance light based on the output signal of each light receiving element. When each light receiving element is under the influence of disturbance light, the control means controls the driving means to drive the rotation means so that each light receiving element is not affected by the disturbance light. In order to rotate the predetermined end of the display means and control its angle, it is not necessary to move the entire optical touch panel until it is in a state where it is not affected by disturbance light as usual, without providing an eaves, etc. The influence of disturbance light can be easily eliminated.

The output signal of each light receiving element is monitored while sequentially rotating each end of the image display means by the rotating means, and each light receiving element receives light from each light emitting element under the influence of disturbance light. Judge whether or not it is not possible, while rotating the end of the image display means to a predetermined angle by the rotation means,
When each light receiving element does not become unaffected by the disturbance light, the rotation means rotates the next end of the image display means, and the rotation means rotates the end of the image display means to a predetermined angle. While moving, at the time when it is determined that each light receiving element is not affected by disturbance light, by stopping the rotation of the end of the image display means by the rotation means,
It is possible to reliably eliminate the influence of disturbance light.

[0013]

FIG. 1 is a flowchart for explaining the operation of an embodiment of the present invention, FIG. 2 is a block diagram of an applied apparatus, and FIG.
2 is an external perspective view of the apparatus in FIG. 2, and FIGS. 4 and 5 are operation explanatory diagrams. However, since the external configuration of the optical touch panel is the same as in FIGS. 6 and 7, these drawings will also be referred to in the following description.

First, the structure of the device will be described. As shown in FIG. 2, the light emitting element driving circuit 11 and the light receiving element driving circuit 12 are controlled by the CPU 13, and the light emitting elements 3 are sequentially turned on by the light emitting element driving circuit 11. While being driven, each light receiving element 4 is driven by the light receiving element driving circuit 12, and the level of the output signal of the light receiving element 4 is
4, a signal corresponding to the detected signal level is output to the CPU 13, and the CPU 13 determines whether the light received by the light receiving element 4 is disturbance light. The control means is constituted by.

Further, based on the output signal of the light receiving element 4,
The drive control unit 15 operates to end the driving of the light receiving element 4 and drive the next light receiving element 4, and the CPU 13 controls the light receiving element driving circuit 12 based on the output of the drive control unit 15. From the first light receiving element 4 to the last n-th light receiving element 4.

An up / down motor 17 as a rotating means for rotating the upper and lower ends and the left and right ends of the image display means 1 backward by predetermined angles respectively in a case not shown in FIG. , A left and right motor 18 and a rotating mechanism, and a first and second motor driving circuit 1 as driving means for driving these motors 17, 18, respectively.
When the CPU 13 determines that the light receiving element 4 is receiving disturbance light, both motor driving circuits 19 and 20 operate according to a control signal from the CPU 13 to operate both motors 17 and 18 respectively. Is driven, and each end of the image display means 1 is rotated in the front-rear direction so that the angle of the image display means 1 is variably controlled so as not to be affected by disturbance light. In this case, a cancel signal is output from the CPU 13 and the detection of the blocking position by the finger 5 is stopped.

At this time, as shown in FIG. 3, the image display means 1 moves the upper end, lower end, left end, right end, upper left end, upper right end, lower left end, lower right end of the case 21 with respect to the case 21. Each end is turned backward as shown by an arrow to an angle set in advance, but the output of the light receiving element 4 is sequentially turned at each end of the image display means 1. If the level of the signal is monitored by the level detection unit 14 and the light receiving element 4 is still affected by disturbance light even if the end of the image display means 1 is rotated backward to the set angle,
After the rotation of the end is stopped and the image display means 1 returns to the reference state before the rotation, the next end is rotated, and the end of the image display means 1 is moved backward to the set angle. When the light receiving element 4 is not affected by disturbance light while being rotated, the rotation of the end is stopped at that position, and the image display means 1 is not affected by disturbance light. Is held.

Further, as an example of such a rotating mechanism of the image display means 1, a vertical rotation axis and a left and right rotation axis passing substantially at the center of the image display means 1 are provided. The shaft is connected to the rotation shafts of the motors 17 and 18 via a gear mechanism or the like, and the rotation of each of the motors 17 and 18 is transmitted so that each end of the image display means 1 rotates backward. ing.

When this optical touch panel is applied to an on-vehicle navigation system, as shown in FIG. 4, the driver's viewpoint is P, and the center point of the optical touch panel is O. The straight line connecting to the point O is in the direction of the angle φ1 to the left and further below the angle φ2 with respect to the front direction from the viewpoint P, and is usually of an optical type so as to directly face the driver's viewpoint P in this positional relationship. A touch panel is arranged.

In general, in a display, CR
In the case of T, the viewing angle range is very wide, and practically, image distortion can be used to the extent that it can be perceptually tolerated. On the other hand, in the case of LCD, the viewing angle range is determined by its properties,
When viewing the LCD panel from outside the viewing angle range, there is a disadvantage that the contrast ratio of the screen is extremely reduced and the display on the screen is completely invisible.

That is, as shown in FIG. 5, the viewing angle range of the LCD is such that the contrast ratio at which the LCD screen can be sufficiently read with reference to the normal direction at the center point of the display screen 2 of the image display means 1 is used as a reference. The angles Δθ11, Δθ12, and Δθ2 as shown in the drawing, which are equal to or greater than “10”, are defined. The viewing angle range of the LCD varies depending on the specification, but as an example, each angle range of a typical LCD is shown in Table 1.

[0022]

[Table 1]

Based on this, the present invention variably controls the angle of the image display means 1 without causing a decrease in the contrast ratio of the image display means 1 when the influence of disturbance light occurs. The rotation angle of each end of the image display means 1 is controlled within the viewing angle range from the state in which the display means 1 faces the driver.

Next, a series of operations will be described with reference to the flowchart of FIG.

First, as shown in FIG. 1, in order to represent the first light receiving element 4 as an initial setting, the light receiving element number m is set to 1 (step T1), and the CPU 13 sets the m-th light receiving element number to m.
After only the light receiving element 4 is driven (step T
2) The light emitting element 3 is controlled by the level detector 14 and the CPU 13.
It is determined whether or not disturbance light having a higher level than the pulse light from the camera is received (step T3). If the determination result is NO, "1" is added to the light receiving element number m (step T3). T4) It is determined whether or not this light receiving element number m is equal to or greater than the total number n of light receiving elements (step T5). If the determination result is NO, the process returns to step T2.

On the other hand, if the decision result in the step T5 is YES, each light emitting element 3 is driven sequentially (step T5).
6), the output signal of the light receiving element 4 is detected (step T)
7) It is determined whether or not the driving of all the sets of light emitting and light receiving elements 3 and 4 has been completed (step T8). If this determination is NO, the process returns to step T6, and the determination is Y.
If ES, the output signal data of all light receiving elements 4 is
The coordinates on the display screen 2 of the set of the light-emitting and light-receiving elements 3 and 4 whose optical path is interrupted by the finger after being captured by the finger 13 are calculated (step T9), and then the process returns to the start.

If the decision result in the step T3 is YES, an angle adjusting process of the image display means 1 is performed (step T10), and the level detecting unit 14 and the CPU 13 set the level higher than the pulse light from the light emitting element 3. It is determined whether or not the disturbance light is still received (step T1).
1) If the result of the determination is NO, the process returns to step T2, and if the result of the determination is YES, a determination is made as to whether or not the adjustment of all the ends of the image display means 1 to be adjusted is completed (step 1). (Step T12), if this determination is NO, the process returns to Step T10; if the determination is YES, C is reached.
A cancel signal is output from the PU 13 to stop the detection of the cutoff position by the finger (step T13), and thereafter, the process returns to the start.

By the way, the angle adjustment processing in step T10 will be described in detail. The upper end of the image display means 1 is first displayed by the up / down motor 17 with the state in which the image display means 1 faces the driver as a reference state. 1 is rotated to a predetermined angle within the viewing angle range shown in FIG.
If U13 does not receive the disturbance light at a higher level than the light from the light emitting element 3 and it is determined that the disturbance light is not affected, the rotation of the upper end portion is stopped at that time, and the rotation to the predetermined angle is performed. If it is still determined that the light is affected by disturbance light, after the image display means 1 is returned to the reference state,
This time, the lower end of the image display means 1 is rotated by the up / down motor 17 to a predetermined angle within the viewing angle range shown in Table 1, and during this rotation, the output signal of the light receiving element 4 is monitored. If the CPU 13 determines that it is not affected by the disturbance light, the rotation of the lower end is stopped at that time. The display means 1 is returned to the reference state.

Then, the left end of the image display means 1 is rotated by the left and right motors 18 to a predetermined angle within the viewing angle range shown in Table 1. During this rotation, the output signal of the light receiving element 4 is monitored, and the level is detected. If the unit 14 and the CPU 13 determine that the disturbance light is not received, the rotation of the left end is stopped at that time, and it is determined that the rotation of the left end is still affected by the disturbance light even if the unit is rotated to a predetermined angle. Sometimes, after the image display means 1 is returned to the reference state, the right end of the image display means 1 is rotated by the left and right motor 18 to a predetermined angle within the viewing angle range shown in Table 1, and this rotation is performed. The output signal of the light receiving element 4 is monitored, and if the level detector 14 and the CPU 13 determine that the signal is not affected by disturbance light, the rotation of the right end is stopped at that point, and even if the rotation is performed to a predetermined angle. In addition, it is affected by disturbance light. When it is determined that the image display means 1 is returned to the state of the reference.

Next, after the upper end of the image display means 1 is rotated to the upper limit angle by the up / down motor 17 and stopped at that position, the left end of the image display means 1 is moved by the left / right motor 18 in this state. It is rotated to a predetermined angle within the viewing angle range shown in Table 1, and during this rotation, the output signal of the light receiving element 4 is monitored. At this time, the rotation of the left end is stopped, and when it is determined that the light is still affected by disturbance light even if the upper end is rotated to the predetermined angle, the left and right ends are rotated to the upper limit angle. The right end of the image display means 1 is rotated by the motor 18 to a predetermined angle within the viewing angle range shown in Table 1. During this rotation, the output signal of the light receiving element 4 is monitored. Affected by If it is determined that there is no influence, the rotation of the right end portion is stopped at that point in time. After the lower end is rotated to the upper limit angle and stopped at that position, the same operation is performed in that state.

Therefore, when each light receiving element 4 is under the influence of disturbance light having a higher level than the light from the light emitting element 3, both driving circuits 19 and 20 are controlled by the CPU 13 so that each light receiving element 4 is controlled. The motors 17 and 18 are driven so as not to be affected by disturbance light, and the output signals of the light receiving elements 4 are monitored while sequentially rotating the respective ends of the image display means 1 to monitor the light receiving elements. It is determined whether or not each light receiving element 4 is not affected by disturbance light, and even if the end of the image display means 1 is rotated to a predetermined angle, each light receiving element 4 is not in a state not affected by disturbance light. In some cases, the rotation of the next end of the image display means 1 is performed, and each light receiving element 4 is not affected by disturbance light while the end of the image display means 1 is rotated to a predetermined angle. Is determined, the rotation of the end of the image display means 1 is stopped. To stop, move each optical touch panel until a conventional state that is not affected by the disturbance light as it no providing the eaves like, it is possible to reliably eliminate the effect of disturbance light.

Incidentally, each means is not limited to the structure shown in the above embodiment, but may be any structure which can achieve the desired functions.

[0033]

As described above, according to the first aspect of the present invention, when each light receiving element is under the influence of disturbance light having a higher level than the light from the light emitting element, it is driven by the control means. Conventionally, the rotating means is driven so that each light receiving element is not affected by disturbance light by controlling the means, and a predetermined end of the image display means is rotated to control its angle. As described above, there is no need to move the entire optical touch panel until it is not affected by disturbance light, and it is not necessary to provide eaves, etc. It is suitable for a system used in an environment that is easily affected.

In addition, the output signal of each light receiving element is monitored while sequentially rotating each end of the image display means by the rotating means, and each light receiving element is influenced by disturbance light. It is determined whether or not each light receiving element is not affected by disturbance light while the end of the image display means is rotated to a predetermined angle by the rotation means. When the next end of the image display means is rotated, and each light receiving element is not affected by disturbance light while the end of the image display means is rotated to a predetermined angle by the rotation means. By stopping the rotation of the image display unit by the rotation unit at the time of the determination, it is possible to more reliably eliminate the influence of disturbance light.

[Brief description of the drawings]

FIG. 1 is a flowchart for explaining the operation of an embodiment of the present invention.

FIG. 2 is a block diagram of an apparatus to which the present invention is applied.

FIG. 3 is an external perspective view of the apparatus shown in FIG.

FIG. 4 is an operation explanatory diagram of the device shown in FIG. 2;

FIG. 5 is an operation explanatory diagram of the device shown in FIG. 2;

FIG. 6 is a plan view schematically showing a general optical touch panel.

FIG. 7 is a cutaway front view of FIG. 6;

FIG. 8 is a flowchart for explaining the operation of the conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Image display means 2 Display screen 3 Light emitting element 4 Light receiving element 13 CPU 14 Level detector 17 Vertical motor 18 Left / right motor 19 First motor drive circuit 20 Second motor drive circuit 21 Case

Claims (2)

(57) [Claims] An image display means is accommodated in a case, and a plurality of light emitting elements are arranged around two adjacent sides of a rectangular display screen exposed at an opening of the case to form a light emitting element row. A plurality of light receiving elements for receiving light from each of the light emitting elements are arranged around the remaining two sides to form a light receiving element row, and a matrix is formed between each of the light emitting elements and each of the light receiving elements. An optical touch panel that forms a light path in a shape of a circle, and detects a blocking position when the light path is blocked by a blocking object such as a finger, and rotates each end of the image display means in the case in the front-rear direction. The image display means is movably attached, and a rotation means is provided for rotating each end of the image display means in the front-rear direction. Each light receiving element is affected by disturbance light based on an output signal of each light receiving element. Each light emission The control means detects whether or not the light from the child cannot be received, and controls the driving means for driving the rotating means by the control means when each of the light receiving elements is under the influence of disturbance light. Driving the rotating means to rotate a predetermined end of the image display means so that the light receiving elements are not affected by disturbance light, and variably controlling the angle of the display screen. An angle control method for an optical touch panel, comprising: 2. The angle control method for an optical touch panel according to claim 1, wherein the output signal of each of the light receiving elements is monitored while sequentially rotating each end of the image display means by the rotating means. It is determined whether or not each of the light receiving elements is in a state where the light receiving elements are not affected by the disturbance light. When the state is not affected, the rotation means rotates the next end of the image display means, and the rotation means rotates the end of the image display means to a predetermined angle. An optical touch panel, wherein the rotation of the end of the image display means by the rotation means is stopped when it is determined that the light receiving elements are not affected by disturbance light. Angle control method.