JPH067389Y2 - Coordinate input device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a coordinate input device which is mounted on the front surface of a display device and detects a coordinate position on the display surface of the display device and inputs the coordinate position to a computer.

[Conventional technology]

As a coordinate input device for manually inputting into a computer, there are various systems such as an electromagnetic induction system, an electrostatic capacitance system, a transparent electrode system, and a light detection system. Among them, a light detection device that is attached to the front surface of the display device and simply presses an arbitrary point on the display surface of the display device with a finger or the like to block the optical path so that the coordinate position can be specified without contacting the detection device. The system type has attracted attention in terms of reliability and operability.

A conventional example of this photo-detection type coordinate input device is shown in FIGS. FIG. 5 is a perspective view showing a state in which the coordinate input device is mounted on the front surface of the display device, FIG. 6 is a sectional view of an essential part of the light receiving element side of the coordinate input device, and FIG. It is a rear view which shows the internal structure of an apparatus.

In these drawings, the coordinate input device includes a frame body 1 formed in a substantially rectangular shape and having an opening 2 in the center, and the frame body 1
A large number of LEs are arranged in rows on the back surface side of the display device, that is, between the frame 1 and the peripheral portion of the display surface 3a of the display device 3 using a CRT (cathode ray tube) or the like.
The light path 10 is blocked from the combination of the light emitting element 4 such as D and the light receiving element 5 such as a phototransistor, and the light emitting element 4 and the light receiving element 5 located at the corresponding positions through the operation area on the front surface side of the display surface 3a. And a light receiving element array 15 and a light receiving element array 15 that form opposite sides to form a substantially rectangular optical element array 13.

The light emitting element 4 and the light receiving element 5 are arranged to emit light from each other.
And the light receiving section 5a are fixed to the substrate 7 provided inside the frame 1 so as to face each other, and
On the front surface of the light-receiving portion 5a of the light-receiving element 5, a light-shielding plate 8 having a light-transmitting hole 8a having a predetermined area is arranged so that only incident light from the light-emitting element 4 forming a pair can be received. . Further, an infrared filter 9 for selectively transmitting infrared rays as an undesired light excluding filter is attached over the entire circumference on the front surface of the light shielding plate 8 and the front surface of the light emitting element 4, that is, the peripheral portion of the operation area. Therefore, an invisible optical path 10 is formed through the infrared filter 9 in the operation area on the front surface side of the display surface 3a.

Next, the input principle of the coordinate input device having the above configuration will be described. Now, for example, as shown in FIG. 5, when the finger 11 or the like is brought into contact with a position to be input on the display surface 3a, the optical path 10 which should pass through the position is blocked, so that the coordinate position is specified. Is possible. That is, by causing the light emitting elements 4 of the light emitting element array 14 to sequentially emit light and scan the light emitting elements 4, the blocked light path 10 can be detected by the light receiving element 5 in each of the x direction and the y direction. 6, the coordinate position is input to the host computer side (not shown).

In addition, in order to improve the mounting accuracy of the light emitting element 4 and the light receiving element 5 on the substrate 7, a coordinate input device employing a light shielding holder 16 as shown in FIG. 8 has been proposed. The light-shielding holder 16 is a housing in which the light receiving element 5 (or the light emitting element 4) is housed in the housing portion 16a and the light transmitting hole 16b is provided on the front surface of the light receiving portion 5a (or the light emitting portion 4a). When the light-emitting element 4 and the light-receiving element 5 are attached to the substrate 7 using the light-shielding holder 16, compared to an attachment structure in which the terminals of these optical semiconductor elements are cantilevered on the substrate 7,
Since there is no possibility that the light emitting element 4 and the light receiving element 5 are tilted with respect to the substrate 7 during mounting, the positioning accuracy is improved.

In the coordinate input device in which this type of shading holder 16 is incorporated, the shading plates 8 shown in FIGS. 6 and 7 are unnecessary.

[Problems to be solved by the invention]

However, in the above-described conventional coordinate input device, the light shielding plate 8 having the light transmitting hole 8a or the light transmitting hole 1 is provided.
Although the directivity of the light that can be incident on the light receiving portion 5a is secured to some extent by the light shielding holder 16 having 6b, the light transmitting holes 8a and 16b are required to have an area that does not impair the detection efficiency. As shown in FIG. 6, it is not possible to block the external light traveling obliquely from above to the light receiving portion 5a, and there is a risk that such external light may reach the light receiving portion 5a and cause a malfunction. In particular, when a strong external light such as a flash of a camera or sunlight acts, the risk of malfunction increases, and in some cases, the light receiving element 5 may be damaged by the strong light.

Therefore, the storage portion 16a of the light-shielding holder 16 has been used so far.
Attempts have been made to extend the front part in a cylindrical shape to have a light-shielding function, but in this case, external light is reflected by the inner wall surface of the extended part and reaches the light receiving part 5a. Therefore, it is insufficient as a measure for preventing malfunction.

Therefore, it is an object of the present invention to provide a highly reliable coordinate input device that can reliably prevent malfunction due to external light.

[Means for solving problems]

To achieve the above object, the present invention comprises an optical element array configured by arranging a large number of light emitting elements and light receiving elements corresponding to the light emitting elements on a substrate, respectively. To form an optical path on the front side of the display surface of the display device,
In a light detection type coordinate input device that detects a position where the optical path is blocked and inputs a coordinate position on a display surface, a light shielding holder is placed on a substrate on which the light receiving element is arranged, and A housing for holding the light-receiving element, a light-transmitting hole located in front of the light-receiving element, and a light-shielding wall located on the display surface side opposite to the light-transmitting hole and protruding in front of the light-transmitting hole are provided. Further, at least the display surface side of the light shielding holder facing the light shielding wall is opened.

[Action]

According to the above means, the external light traveling obliquely from above to the light receiving portion of the light receiving element is blocked by the light shielding wall of the light shielding holder, and since the portion of the light shielding holder facing the light shielding wall is opened, the external light is prevented. There is no possibility of being reflected and reaching the light receiving portion.

〔Example〕

 Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 and 2 are for explaining one embodiment of the present invention. FIG. 1 is a sectional view of a main part of a coordinate input device, and FIG. 2 is a light shield required for this coordinate input device. FIG. 8 is a perspective view of the holder, and parts corresponding to those in FIGS. 5 to 7 are designated by the same reference numerals.

As shown in FIG. 1, the light receiving element 5 of this coordinate input device
Is fixed to the substrate 7 in a state of being incorporated in a light-shielding holder 20 having an appearance shown in FIG. This shade holder 2
Reference numeral 0 denotes a storage portion 20a that stores the light receiving element 5 to enhance the positioning accuracy with respect to the substrate 7, a light transmission hole 20b formed in a portion of the storage portion 20a that covers the front surface of the light receiving element 5, and
The upper surface of the storage portion 20a, that is, a light shielding wall 20c formed by extending a wall surface on the side opposite to the display surface 3a forward.

Therefore, the external light entering from the obliquely upper direction toward the light receiving section 5a cannot be reached by the light blocking wall 20c of the light blocking holder 20 and reach the light receiving section 5a, and the light blocking wall of the light blocking holder 20 cannot be reached. Since the portion facing 20c is open, there is no concern that external light will be reflected by the light shielding holder 20 and reach the light receiving portion 5a. In other words, the light-shielding holder 20 is provided with a light-shielding side 20c on the incident side with respect to external light coming from obliquely above, which may cause a malfunction, and the portion facing the light-shielding wall 20c is antireflection. Therefore, since it is opened, there is no possibility that external light reaches the light receiving portion 5a of the light receiving element 5 in the storage portion 20a, and it is possible to reliably prevent malfunction due to external light.

FIGS. 3 and 4 are for explaining another embodiment of the present invention. FIG. 3 is a front view of a main part of the coordinate input device, and FIG.
The figure is a perspective view of a light-shielding holder used in this coordinate input device, and parts corresponding to those in FIGS. 1 and 2 are designated by the same reference numerals.

In this embodiment, the light receiving element 5 located at the corner of the optical element array is used.
On the other hand, it differs from the above-described embodiment in that the light shielding holder 20 having the light shielding walls 20c and 20d having an L-shaped cross section is mounted. That is, in addition to the light blocking wall 20c for blocking the external light incident from diagonally above in the light blocking holder 20,
As shown in FIG. 3, a light shielding wall 20d for blocking undesired light reflected by the infrared filter 9 and traveling toward the light receiving portion 5a.
Is provided to prevent malfunction caused by reflected light as well as external light.

In the case of the above embodiment, the light blocking wall 20d must be provided on the side that blocks reflected light that may cause a malfunction.
For example, at the other end of the light-receiving element array including the light-receiving element 5 shown in FIG. 3, the light-shielding holder 20 in which the light-shielding wall 20d is formed in a symmetrical position with respect to FIG.

[Effect of device]

As described above, according to the present invention, external light traveling obliquely from above to the light receiving portion of the light receiving element is blocked by the light blocking wall of the light blocking holder incorporating the light receiving element, and
Since the portion of the light-shielding holder that faces the light-shielding wall is open, there is no risk of external light being reflected and reaching the light-receiving portion.
A malfunction due to external light can be reliably prevented.

[Brief description of drawings]

1 and 2 are for explaining one embodiment of the present invention. FIG. 1 is a sectional view of a main part of a coordinate input device, and FIG. 2 is a perspective view of a light-shielding holder used therein. FIGS. 3 and 4 are for explaining another embodiment of the present invention. FIG. 3 is a front view of a main part of the coordinate input device, and FIG. 4 is a view of a light-shielding holder used therein. FIG. 5 to FIG. 7 are perspective views for explaining a conventional example, and FIG. 5 is a perspective view showing a state in which the coordinate input device is mounted on the front surface of the display device.
FIG. 6 is a sectional view of the main part of the coordinate input device, FIG. 7 is a rear view showing the internal structure of the coordinate input device, and FIG. 8 is a sectional view of the main part of the coordinate input device according to another conventional example. . 3a ... Display surface, 4 ... Light emitting element, 5 ... Light receiving element, 5
a ... light receiving part, 20 ... shading holder, 20a ... storage part, 20b ... light transmitting hole, 20c ... shading wall.

Continuation of the front page (56) Reference JP-A-55-110330 (JP, A) JP-A-55-115167 (JP, A) JP-A-58-211245 (JP, A) Actual development Sho-56-124859 (JP , U)

Claims (1)

[Scope of utility model registration request] 1. An optical element array constituted by arranging a plurality of light emitting elements and light receiving elements corresponding to the light emitting elements on a substrate in rows, wherein the light emitting elements and the light receiving elements are provided on a display surface of a display device. In a light detection type coordinate input device that forms an optical path on the front surface side, detects the position where the optical path is blocked, and inputs the coordinate position on the display surface, a light shielding holder is mounted on the substrate on which the light receiving element is arranged. And a light-transmitting hole that is located in front of the light-receiving element, and a front portion of the light-transmitting hole that is located opposite to the light-transmitting hole. The coordinate input device is characterized in that a light-shielding wall that protrudes to the inside is provided, and at least a display surface side of the light-shielding holder facing the light-shielding wall is opened.