JP2002244814A - Multi-display system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multi-display system capable of correcting a deviation in optical axis caused by temperature or another disturbance and achieving stable performance by actively adjusting the optical axis of a laser beam emitted from a detector unit using a laser diode, a retroreflection film and a PSD for position detection. SOLUTION: The multi-display system has a shaft 10 for rotating position detector units 2 and 3 upward/downward to be driven and controlled by a motor 12. The shaft 10 is located coaxially with the axis including the emitting point of the laser beam L from the laser diode 5. The emitting direction of the laser beam L is adjusted by actively moving the position detector units 2 and 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a multi-display system using contact coordinate detection.

[0002]

2. Description of the Related Art A multi-touch panel type multi-touch panel for detecting a touch position in a panel using two detection units using a laser diode, a retroreflective film and a PSD for position detection. In the display system, the housing of the detection unit is slightly deformed due to the heat of the laser diode and changes in the ambient temperature, so that the laser does not hit the retroreflective film at the correct position, and the output power is thereby reduced. Changes,
There is a problem that the touched position is difficult to detect or cannot be detected, and a solution has been desired.

[0003]

According to a first aspect of the present invention, there is provided a multi-display system comprising two detection units each using a laser diode, a retroreflective film, and a PSD for position detection. In a multi-display system with a touch panel capable of detecting the touch position in the panel using the detection unit, the detection unit includes:
It has an adjusting means for automatically adjusting the mounting position.

In order to achieve the above object, the multi-display system according to claim 2 is characterized in that, in the multi-display system according to claim 1, the adjusting means automatically performs the adjustment when power is turned on. And

[0005] In order to achieve the above object, the multi-display system according to the third aspect is the first or second aspect.
In the multi-display system, the detection unit has a temperature detecting means for detecting a temperature, based on the temperature detected by the temperature detecting means and a preset correction table, the adjusting means, the mounting position of the mounting position Automatic adjustment is performed.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view (A) showing an embodiment of a multimedia display system according to the present invention, and an enlarged perspective view (B) of a main part. In the figure, reference numeral 1 denotes a panel, which often uses a plasma display or an LCD. In the case of this example, an LCD projector is built in the main body 13 and is a type that projects onto the panel 1 from the back. In the figure, reference numerals 2 and 3 denote position detection units which detect the position of the panel 1 when touched with a finger or a pen, and serve as a mouse or the like in a computer, for example.

FIG. 2 is a diagram showing the principle of position detection in the apparatus shown in FIG. From one detection unit 2, 3, the angle θ
Is irradiated with the laser light L in the range of. The angle θ is set so as to cover the corner of the panel 1 as a matter of course.

When a shielding object such as a finger is placed at the position a on the panel 1, the laser beam L at that portion is blocked, and a shadow is created at the position a '. In the figure, reference numeral 4 denotes a retroreflective film on which a sheet having the property of reflecting light in the incident direction of the light is adhered. The laser beam reflected at the position a 'returns to the position detecting unit 2, The position is detected by the PSD inside. The position a can be calculated by arranging two such position detection units at adjacent corners of the panel 1 as shown in FIG.

FIG. 3 is a perspective view showing the internal structure of the position detecting units 2 and 3. 5 is a laser diode in the figure.
The laser light L emitted from this is spread in the horizontal direction by the lens 6 and has the above angle θ. Further, the lens 6 has a curvature for converting it into parallel light in the vertical direction, and the laser light L does not diffuse in the vertical direction. In the drawing, reference numeral 7 denotes a half mirror, which transmits the emitted light, reflects the light from the reflection film, and condenses the light on the PSD 8.

FIG. 4 is a plan view of FIG. 3 as viewed from above, and FIG. 5 is a side view of the same. FIG. 6 is an external view of the position detection units 2 and 3 in which the above-described configuration is housed in a housing and unitized. In the figure, reference numeral 14 denotes a color filter which is installed to block disturbance light and the like.

The laser light L emitted from the position detection units 2 and 3 is projected on a retroreflective film 4. This is shown in FIG. FIG. 7 is an enlarged view of left corner portion A of panel 1 shown in FIG. The laser beam L spread in a flat fan shape is condensed on the retroreflective film 4 in a straight line as indicated by an arrow 9 in the figure. At this time, as shown in FIG. 8A, light runs parallel to the surface of panel 1 and hits retroreflective film 4. At this time, the smaller the value of dimension H, the better. This is because if the dimension H is large, the panel 1 is detected before touching the panel 1 with a finger or the like, and the sense of touch and detection is shifted.

Experimentally, the dimension H is a reasonable value of about 1 to 3 mm. However, when the laser diodes are turned on in the position detection units 2 and 3, the heat thereof may slightly deform the housing of the position detection unit, causing a shift in the above-described condensing point. That is, as shown in FIGS. 8B and 8C, the retroreflective film 4 comes off. In this case, a regular output cannot be obtained, and the possibility of erroneous detection increases. This phenomenon becomes more conspicuous as the size of the panel 1 increases. This is because the farther the light condensing position is, the larger the deflection at the tip becomes. A similar problem appears even when the ambient temperature changes. It is a big problem.

Therefore, as shown in FIG. 1 (B), in this embodiment, a shaft 10 is provided so that the position detecting units 2 and 3 can be turned up and down, and the drive is controlled by a motor 12. Having a configuration. The axis 10 is desirably coaxial with the axis including the emission point of the laser light L from the laser diode 5. In the figure, reference numeral 11 denotes a reduction gear. The emission direction of the laser light L is adjusted by positively moving the position detection units 2 and 3. That is, FIG.
The emission direction of the laser light L is moved from the state (B) to the state (C), the optical axis is calculated from the output of the PSD, the optical axis is stopped at a proper position, and the deviation of the optical axis is corrected. Note that the above adjustment may be automatically performed when the power of the system is turned on.
A temperature sensor may be provided in each of the position detection units 2 and 3, and the above-described automatic adjustment may be performed based on the detected temperature and a preset correction table.

[0014]

As described above, according to the multi-display system of the first aspect of the present invention, the light of the laser beam emitted from the detection unit using the laser diode, the retroreflective film and the PSD for position detection. By positively adjusting the axis, the deviation of the optical axis due to temperature and other disturbances can be corrected, and there is an effect that stable performance can be obtained.

[0015] In the multi-display system according to the second aspect of the present invention, as described above, the adjusting means includes:
Since the above-mentioned adjustment is automatically performed when the power is turned on, there is an effect that, in addition to the above-mentioned common effects, a deviation due to some cause when not in use can be corrected.

As described above, the multi-display system according to the third aspect of the present invention detects the temperature in the detection unit and, based on the pre-installed correction data of the deformation amount of the housing at that temperature. Since the correction is made immediately, in addition to the above-mentioned common effects, there is an effect that the deviation due to the temperature change due to long-term use is also corrected, and the use can always be performed in an optimum state.

[Brief description of the drawings]

FIG. 1A is a perspective view showing an embodiment of a multimedia display system according to the present invention, and FIG.

FIG. 2 is a diagram showing a principle of position detection in the apparatus of FIG.

FIG. 3 is a perspective view showing an internal configuration of a position detection unit.

FIG. 4 is a plan view of FIG. 3 as viewed from above.

FIG. 5 is a side view of the same.

FIG. 6 is an external view of a unitized position detection unit.

FIG. 7 is a perspective view showing a state in which laser light emitted from a position detection unit is projected on a retroreflective film.

FIG. 8 is a sectional view of the same.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Panel 2, 3 Position detection unit 4 Retroreflective film 5 Laser diode 6 Lens 7 Half mirror 8 PSD 10 Position detection unit axis 11 Gear for deceleration 12 Motor 13 Main body 14 Color filter L Laser light

Claims (3)

[Claims] 1. A multi-display system with a touch panel capable of detecting a touch position in a panel by using two detection units using a laser diode, a retroreflective film and a PSD for position detection, wherein the detection unit is A multi-display system having an adjusting means for automatically adjusting its mounting position. 2. The multi-display system according to claim 1, wherein said adjusting means automatically performs said adjustment when power is turned on. 3. The multi-display system according to claim 1, further comprising a temperature detecting means for detecting a temperature in said detecting unit, based on the temperature detected by said temperature detecting means and a preset correction table. Wherein the adjusting means automatically adjusts the mounting position.