JPH0337071Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an optical touch panel, and more particularly to an optical touch panel that optically detects a touch input point on a display screen of a cathode ray tube display device.

[Conventional technology]

Conventionally, as a touch panel for detecting touch input points on the display screen of a cathode ray tube (CRT) display device, light emitting elements are arranged along one of two opposing sides of the screen, and each light emitting element is arranged along the other side. An optical touch panel is used that detects a touch input point by arranging light receiving elements that form a pair with the element and detecting a place where light emitted from a light emitting element is blocked when a touch input is made. In conventional optical touch panels for CRT display devices, two pairs of a light-emitting array in which light-emitting elements are arranged in a linear row and a light-receiving array in which light-receiving elements are arranged in a linear row are placed opposite each other. They are provided along the periphery of the display screen in orthogonal directions, and the abscissa and ordinate coordinates of the touch input location are detected by detecting the light-blocking locations in each pair.

[Problem that the invention attempts to solve]

In the above-mentioned conventional optical touch panel for a CRT display device, since the display screen of a normal CRT is curved in a spherical or cylindrical shape, light is emitted from each light emitting element and received by the light receiving element facing it. The distance between the optical path traveled by the camera and the display screen varies depending on the location. In order to minimize the distance between this optical path and the display screen, in conventional optical touch panels, the light emitting array and light receiving array are arranged so that the optical path is parallel to the tangential plane at the center of the display screen. be. However, even with such an arrangement, it is inevitable that the distance between the optical path and the display screen increases as one approaches the periphery of the display screen. On the other hand, the pointing direction during touch input is not necessarily perpendicular to the plane formed by both the vertical and horizontal optical paths, and touch input is often performed in a considerably inclined pointing direction. As a result, there is a problem in that the deviation between the touch input location on the display screen and the light-shielded location due to the touch input increases, particularly as the touch approaches the periphery of the display screen, and erroneous detection of the input location is likely to occur.

The purpose of this invention is to solve the above-mentioned problems and to reduce the deviation from the touch input point on the display screen when performing touch input in an inclined pointing direction, thereby preventing erroneous detection of the input point. The purpose of the present invention is to provide an optical touch panel.

[Means for solving problems]

The touch panel of the present invention has an array of light emitting elements disposed on a pair of opposite sides in front of a display screen whose surface has a curved cross-section and at least one of its longitudinal cross-sections. and an array of light receiving elements disposed on the other side of the pair of sides, wherein the pair of sides facing perpendicularly to the curved cross section has the display A light emitting element array is placed on the first side of the pair of sides on the second side so as to transmit and receive a luminous flux passing close to one of two areas obtained by dividing the screen in the center by an assumed line parallel to the pair of sides. A light emitting element array is disposed on the second side of the first light transmitting/receiving pair on which a light receiving element array is disposed, and a light emitting element array is disposed on the first side so as to transmit and receive a luminous flux that passes close to the other one of the two areas. and the second light transmitting/receiving pair in which a light receiving element array is arranged.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

Figures 1a and 1b are a perspective view and a cross-sectional view, respectively, showing an embodiment of the present invention. In Figure a, a display screen 3 of a cathode ray tube (CRT) of a display device 2 is curved into a spherical shape. A frame 1 provided around the display screen 3 is a frame plate on which light emitting elements 10 and light receiving elements 11 are arranged and attached. On the inner surface of the frame 1 on the right side when viewed from the front of the display screen 3, there is a light receiving element 1 on the side closer to the display screen 3.
A light-receiving array in which light-emitting elements 10 are arranged in a linear row is provided, and a light-emitting array in which light-emitting elements 10 are arranged in a linear row is provided outside the light-receiving array. Also on the inner surface of the left side of the frame 1, a light receiving array is provided on the side closer to the display screen 3, and a light emitting array is provided on the outside thereof. When the light emitting element 10 on the right side of the frame 1 emits light, the emitted light passes close to the display screen 3 in the left half of the display screen 3, as shown by the broken line arrow A, and enters the light receiving element 11 on the left side of the frame 1. . Also, frame 1
When the light emitting element 10 on the left side emits light, the emitted light passes close to the right half of the display screen 3, as shown by the broken line arrow B, and enters the light receiving element 11 on the right side of the frame 1. The two-dot chain line S indicates the projection line of the optical path indicated by the dashed arrow A or B onto the display screen 3, and FIG. 1b shows a top view of a cross section taken along this projection line. As mentioned above, for example, display screen 3
As seen from the front, the light path emitted from the light emitting element 10 on the right side and entering the light receiving element 11 on the left side is parallel to the tangent at the center of the left half of the display screen 3 (as seen from the front), as shown by the broken line arrow A. The arrangement positions of the light emitting element 10 and the light receiving element 11 are set so that the light emitting element 10 and the light receiving element 11 are oriented in the same direction and close to the display screen 3. Similarly, one row of light emitting arrays and one row of light receiving arrays are provided on each inner surface of the upper and lower sides of the frame 1, so that an optical path passes close to the upper half of the display screen 3 and an optical path passes close to the lower half of the display screen 3. It is designed so that you can get the following.

In this way, in this embodiment, two pairs of light-emitting arrays and two light-receiving arrays are provided in each of the horizontal and vertical directions, and the luminous flux obtained from these two pairs is curved into a spherical shape for the display screen. 3
It is designed to pass close to the screen in an area divided into two. During touch input, two pairs of light beams are sequentially blocked in both the horizontal and vertical directions at the pointing point of the input, so the one of the two pairs of light beams that is blocked later, that is, the display screen 3 By detecting the shading point of the luminous flux closer to
The touched location on the display screen 3 can be detected more accurately than before.

If one row of light-emitting arrays and one row of light-receiving arrays are provided on each side as in this embodiment, the directions of the two pairs of light beams are opposite to each other, so even if both light beams are generated at the same time, they will not be emitted from the light-emitting array on one side. This has the advantage that there is no risk of false detection due to simultaneous reception of light by the light receiving arrays on both sides.

Note that when the display screen 3 is curved in the shape of a cylindrical surface, only one pair of light beams is required in the generatrix direction of the curved surface. That is, it is clear that the light emitting array and the light receiving array corresponding to the generatrix direction can each be arranged in one row.

[Effect of idea]

As explained above, the present invention has the effect of realizing an optical touch panel that can reduce the detection error of the input point caused by the tilt of the pointing direction during touch input compared to the conventional one.

[Brief explanation of the drawing]

Figures 1a and 1b are a perspective view and a cross-sectional view, respectively, showing an embodiment of the present invention. 1... Frame, 2... Display device, 3... Display screen, 10... Light emitting element, 11... Light receiving element.

Claims (1)

[Claims for Utility Model Registration] A light-emitting element disposed on one side of a pair of sides facing each other in front of a display screen in which at least one of the cross-sectional and longitudinal cross-sections of the surface is curved. In an optical touch panel provided with a light transmitting/receiving pair having an array of and an array of light receiving elements arranged on the other side of the pair of sides, the pair of sides oriented perpendicular to the curved cross section, A second light emitting element array is arranged on the first side of the pair of sides so as to transmit and receive a light flux passing close to one of two areas obtained by dividing the display screen in the center by an assumed line parallel to the pair of sides. The first light transmitting/receiving pair has a light receiving element array arranged on its side, and the first light transmitting/receiving pair has a light emitting element array arranged on its second side so as to transmit and receive a light flux passing close to the other one of the two areas. An optical touch panel characterized in that a second light transmitting/receiving pair having a light receiving element array arranged on one side thereof is provided.