JPH01147418A - Optical non-contact keyboard - Google Patents

Abstract

PURPOSE:To prevent the generation of time aging and a contact failure by providing a light cut-off object for cutting off a light beam by depressing a button, radiating the light beam to each button from three directions and detecting the depressed button, based on a result of its photodetecting. CONSTITUTION:Plural light emitting body groups 1a-1c and light receiving body groups 2a-2c which have been arranged in one line so as to correspond to a key array are positioned in three directions against a button group which has been arranged in a matrix shape, respectively, and light beams a-c are radiated from three directions to one button 3 and photodetected. To a button axis, a light cut-off object 4 is attached, and usually, the light beam passes through a transparent part of the button axis, and when the button 3 is depressed, the light cut-off object 4 cuts off the light beam. Therefore, by executing a scan from three directions to each button, the depressed button can be easily detected. In such a way, since there is no mechanical contact, a contact failure caused by time again does not occur, and also, deterioration caused by dust, moisture, etc., is not generated.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to a button operation board (keyboard) used for data input, and in particular, a plurality of buttons are arranged in a matrix, and the pressed state of each button can be detected optically. The present invention relates to an optical contactless keyboard that can be detected visually.

[Prior Art] Conventionally, this type of keyboard has been configured with key switches having mechanical contacts, and a key depression IE has been detected by detecting on/off of each individual switch.

[Problems to be Solved by the Invention] However, since the above-mentioned conventional keyboard has mechanical contacts, it is prone to poor contact due to aging or excessive use, and deterioration due to dust, moisture, etc. There were drawbacks.

[Means for Solving the Problems] In order to achieve the above object, the optical contactless keyboard according to the present invention is attached to each button on an operation board in which a plurality of buttons are arranged in a matrix. A light shielding object that blocks the light beam when the button is pressed, a light emitter that irradiates light beams from three directions to each button, and a photoreceptor that receives the light beam from the light emitter are provided. Based on this, the pressed button can be detected.

[Example] Next, an example of the present invention will be described with reference to the drawings.

FIG. 1 is a diagram showing the configuration of an optical contactless keyboard according to an embodiment of the present invention.

In the figure, la, lb, and lc are a plurality of light emitting bodies arranged in a line corresponding to the key arrangement. Each group of light emitters is positioned in three directions with respect to the button group arranged in a matrix.
and la, lb in Figure 2.

As shown in lc, the structure is such that one button is irradiated with light beams a, b, and c from three directions, and each button has three light emitters corresponding to a plurality of buttons.

2a, 2b, and 2c are a group of photoreceptors that correspond to the light emitters and receive light beams on a one-to-one basis. This is also the luminous body group 1a, l
Like b and lc, they are located in three directions.

3 is a group of buttons arranged in a matrix 0
The shaft of each button is transparent, and a spring 5 is connected to the lower end of the shaft. A light blocker 4 is attached to this button shaft as shown in Fig. 2. Normally, the light beam passes through the transparent part of the button shaft, and when the button is pressed, the light blocker 4 blocks the light beam. The structure is such that

Next, the operation of this embodiment will be explained with reference to FIG.

FIG. 3 is a diagram showing a method for detecting pressed buttons when two buttons are pressed at the same time.

First, when buttons A1 and A2 are pressed, the press of button A1 is detected by the photoreceptors All, A21 . A3
1 indicates no light reception, O mark in the figure indicates no light reception, and X mark indicates light reception), and press detection of button A2 is performed by light receptors A12. A22. A32 is performed without receiving any light.

Next, when buttons Bl and B2 are pressed, the press of button B1 is detected by the photoreceptor Bll.

B21. B31 is detected when no light is received, and the press of the button B2 is detected by the photoreceptor B12. B22. B32 is performed without receiving light.

Further, the broken line buttons in the figure indicate buttons that are erroneously detected when pressed button detection is performed using light beams from two directions. In this way, when a pressed button is detected by scanning from two directions, false detection occurs, but by scanning each button from three directions as in this embodiment, it is easy to detect the pressed button. Detection becomes possible.

[Effects of the Invention] As explained above, the present invention provides each button with a light blocking object that blocks light when the button is pressed, irradiates the button with light rays from three directions, and directs the irradiated light to the photoreceptor. By receiving light at the sensor, the press of the button can be detected with a single function, resulting in the following effects.

■Extremely long lifespan as it has no mechanical contacts.

■Since there are no mechanical contacts, there is no contact failure due to aging.

■No deterioration due to dust, moisture, etc., and is resistant to environmental conditions.

■Key matrix scanning is performed optically, reducing the number of parts, simplifying the structure, and lowering costs.

[Brief explanation of the drawing]

FIG. 1 shows the structure of an optical contactless keyboard according to an embodiment of the present invention, FIG. 2 shows the structure of the buttons of the optical contactless keyboard, and FIG. 3 shows the buttons of the optical contactless keyboard. FIG. 3 is an explanatory diagram of a pressed state detection method. la, lb, lc: light emitter group 2a, 2b, 2c: photoreceptor group 3: button group 4: light blocker 5: spring

Claims (1)

[Claims] In an operation board in which a plurality of buttons are arranged in a matrix, a light blocking object is attached to each button and blocks a light beam when the button is pressed, and a light beam is directed to each button from three directions. An optical contactless keyboard comprising: a light emitter that emits light; and a light receiver that receives light from the light emitter, and can detect a pressed button based on a result of light reception by the light receiver.