JP3525363B2 - Object detection means in touchless panel switch - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an object detecting means in a touchless panel switch, and more particularly to a touchless panel switch using a capacitance type proximity sensor (switch). The present invention relates to a finger detection device. 2. Description of the Related Art One of the inventors of the present invention has previously invented and proposed a device which is a touchless panel switch (hereinafter referred to as a touchless panel) (Japanese Patent Application No. Hei. −
333727). FIG. 3 is a schematic perspective view of a touchless panel and a conventional object detecting means. This is an input / output terminal device comprising a display 1, a gradient index lens element 3, and an object detecting means 13. A display screen 2 (object surface) is brought into the air by the gradient index lens element 3. The switch input operation is performed by transmitting and selecting the image plane 4 displayed in the air with a finger, that is, detecting that the finger has entered a predetermined area near the image plane 4 displayed in the air. . The object detecting means 13 which is a component of the touchless panel is a member for detecting whether or not an object, that is, a finger of an operator of the device has entered a detection range without contact. The configuration is a matter of design choice for a person skilled in the art and is free. Therefore, if the object detection means 13 of the touchless panel is to be realized by the conventional technique, it is necessary to install a sensor for detecting intrusion of a finger around both surfaces transmitted in the air, that is, around the image plane 4 first. Considered as a matter of course. In this case, an optical sensor, for example, a phototransistor as a light receiving element and a light emitting diode as a light emitting (light emitting) element can be used as the sensor. Also,
As a method of arranging the optical sensors, it is conceivable to form a matrix of light scanning lines as is often used in a touch panel. In FIG. 3, a matrix of light scanning lines is formed by a light emitting element array 11a and a light receiving element array (not shown) for scanning in the X-axis direction and a light emitting element array (not shown) for scanning in the Y-axis direction. 3) and an arrangement method of an optical sensor configured by combining the light receiving element rows 12b. When a sensor is provided around the image plane 4, an optical sensor other than the light emitting diode and the phototransistor and a sensor other than the optical sensor such as an ultrasonic sensor may be used as the sensor. In the configuration in which the detecting means (sensor) is installed around the image plane 4 displayed in the air, regardless of which sensor and which detection method is used, the sensor is mounted at a predetermined position around the image plane 4. A member such as a frame was required. In FIG. 3, the sensor mounting frame 10 is the member. If the conventional technique is to constitute a finger detection means for a touchless panel, this sensor mounting frame 1
Since a member equivalent to 0 is required, the size of the entire touchless panel tends to be large.
There is a problem that the sensor mounting frame 10 and a member (not shown) that supports the sensor mounting frame 10 become an obstacle when selecting with a finger. SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and an object of the present invention is to provide a touchless panel with an image plane 4. It is an object of the present invention to provide an object detecting means capable of detecting a finger that has entered the vicinity of the image plane 4 without installing a member such as the sensor mounting frame 10 around the camera. The object detecting means in the touchless panel according to the present invention has attained the above-mentioned object and is as follows. At a predetermined position between the gradient index lens element and the image plane, a detection electrode of a capacitance type proximity sensor is provided, and the detection electrode includes
Uses transparent material. How many detection electrodes are provided between the gradient index lens element and the image plane is a matter of design choice by those skilled in the art, and is determined by the number of keys (switches) displayed on the display screen. Just fine. The object detecting means in the touchless panel according to the present invention comprises a detecting electrode made of a transparent material of a capacitance type proximity sensor, that is, a transparent electrode, between the image plane and the gradient index lens element. Although a predetermined number is provided, the operation of each capacitance type proximity sensor is the same, so that the operation will be described using one capacitance type proximity sensor as a representative. When an operator of a device enters a finger into an arbitrary area of the image plane, the finger is moved to a transparent electrode of a capacitance type proximity sensor which is in charge of detecting the finger that has entered the area. You have approached. The capacitance type proximity sensor is a sensor that utilizes the fact that the capacitance between an object and the sensor is inversely proportional to the distance between the two. An oscillation circuit is connected to an electrode for detecting the object,
An object is detected by starting or stopping the oscillation of the oscillation circuit or changing the oscillation frequency. When the distance between the finger and the transparent electrode becomes smaller than a predetermined distance, the capacitance-type proximity sensor changes its state, such as starting or stopping oscillation. Can be detected as having entered a predetermined area. In the present invention, since the detection electrode of the capacitance type proximity sensor is a transparent electrode, the screen of the display is transmitted to the image surface via the transparent electrode by the refractive index distribution type lens element. You. Therefore, even if the transparent electrode is present between the image plane and the distributed refractive lens element, the touchless panel does not hinder transmission of the screen of the display to the image plane. FIG. 1 and FIG. 2 are diagrams schematically showing one embodiment of the present invention. The display 1 and the gradient index lens element 3 are installed such that the display screen 2 is transmitted to the image plane 4 by the gradient index lens element 3. The method of holding the gradient index lens element 3 is a matter of design choice by a person skilled in the art and is free. The number, shape and size of keys (switches) displayed on the image plane 4 in the air are a matter of design choice by those skilled in the art and are free. In FIGS. 1 and 2, two keys are displayed in the left-right direction on the paper. The capacitance type proximity sensor 5 comprises a transparent electrode 6 and a detection circuit section 9 and is provided at least one for each key displayed on the image plane 4 or for each predetermined detection area. In order to reliably detect a finger that has entered the image plane 4 and the space above and below it, one detection area (or key)
It is advantageous to provide a plurality of capacitance type proximity sensors for
If there is one capacitance type proximity sensor 5 for each, it is possible in principle to detect a finger. The following description of the embodiment is based on an example in which one capacitance type proximity sensor is provided for each key. When a finger (not shown) enters the image plane 4, the capacitance between the transparent electrode 6 of the capacitance type proximity sensor 5 and the finger to be detected changes, and oscillation occurs. The oscillation frequency of the circuit 7 changes. The switching circuit 8 detects the change of the oscillation frequency as ON / OFF of the built-in switching element. Although FIGS. 1 and 2 show that the detection circuit section 9 is provided with an oscillation circuit 7 and a switching circuit 8, the detection circuit section 9 and its constituent oscillation circuit 7 The specific configuration of the switching circuit 8 is a matter of design choice by a person skilled in the art, and can be sufficiently made by a known technique relating to a capacitance type proximity sensor. A transparent material is used for an electrode of the capacitance type proximity sensor 5 for detecting an object. The position where the transparent electrode 6 is provided may be anywhere between the image plane 4 and the gradient index lens element 3. It may be provided at an intermediate position between the image plane 4 and the gradient index lens element 3 as shown in FIG. 1, or may be arranged close to the gradient index lens element 3 as shown in FIG. In any case, it is clear that the object detecting means in the touchless panel according to the present invention does not need to provide a member such as a frame for holding the transparent electrode 6 around the image plane 4. is there. As described above, in the present invention, the sensor mounting frame and the members supporting the sensor mounting frame do not exist around the image plane 4, and the transparent electrode 6 is supported and fixed below the image plane 4. When the image plane 4 is selected by a finger, these members do not interfere. Since the present invention is configured as described above, it has the following effects. The transparent electrode 6 of the capacitance type proximity sensor 5 is disposed between the image plane 4 and the gradient index lens element 3 to detect an object entering a predetermined space including the image plane 4. Since the detection is performed by the capacitance type proximity sensor 5, it is not necessary to provide a member such as a sensor mounting frame around the image plane 4, and it is possible to provide an object detection unit in a touchless panel.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram showing one embodiment of the present invention. FIG. 2 is a schematic diagram showing one embodiment of the present invention. FIG. 3 is a diagram showing a touchless panel and a conventional object detecting means thereof. Schematic perspective view [Description of reference numerals] 1 Display 2 Display screen 3 Refractive index distribution type lens element 4 Image surface 5 Capacitive proximity sensor 6 Transparent electrode 7 Oscillation circuit 8 Opening / closing circuit 9 Detection circuit unit 10 Sensor mounting frame 11a Light emitting element array 12b Light receiving element array 13 Object detecting means

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-6-348404 (JP, A) JP-A-6-348817 (JP, A) JP-A-6-51906 (JP, A) JP-A-7-348 114866 (JP, A) JP-A-3-46724 (JP, A) JP-A-2-66825 (JP, A) JP-A-5-127828 (JP, A) JP-A-63-45625 (JP, A) JP-A-63-175146 (JP, A) JP-A-4-35950 (JP, U) JP-A-61-12138 (JP, U) JP-B-61-45252 (JP, B2) (58) (Int.Cl. ⁷ , DB name) H01H 35/00-36/00 G06F 3/033

Claims (1)

(57) A touchless panel switch for transmitting a screen of a display to an image plane in the air by a gradient index lens element, wherein the gradient index lens element and the image plane are transmitted. A detection electrode of the capacitance type proximity sensor is provided at a predetermined position between the two, and a transparent material is used for the detection electrode.