JPH0429473Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to an optical panel switch with a flat touch surface for various control devices such as electronic equipment.

[Conventional technology and problems]

Conventionally, in order to improve the operability of various AV equipment such as televisions, video decks, VD (video disc) players, CD (compact disc) players, tuners, and cassette decks, wireless remote control devices have generally been adopted. This allows various operations such as power on/off, volume increase/decrease, channel switching, start/stop, fast forward/rewind, etc., but it does not affect other devices. In addition, infrared type devices are often used because the device configuration is relatively simple.

However, in order to enable a variety of operations, this type of infrared remote control device has a large number of switches corresponding to each function arranged on its panel surface. In some cases, it becomes difficult to determine which switch to operate, and even though these infrared remote control devices were adopted to improve the operability of various AV devices, they actually make operation more cumbersome. There was a problem with this.

For this reason, for example, if light rays are irradiated vertically and horizontally in a matrix on the surface of the liquid crystal display element that makes up the display panel surface, and when the display area shown on the surface of the liquid crystal display element is touched with a finger, the light beams will appear vertically and horizontally as described above. There is an optical switch type panel switch in which the touch position can be recognized by blocking the irradiated light beam and detecting this by the light receiving element receiving the light beam, but in this case, the light path is in a matrix shape. Since the panel surface is arranged on a flat surface, a wall section is required for arranging the light emitting element and the light receiving element on the side of the panel surface that is touched by the fingers, which makes it impossible to form the panel surface flat. Ta.

In addition, a panel switch using transparent electrodes is also known, for example, from Utility Model Publication No. 16301/1983.
In this case, the transparent electrodes were visible, resulting in an unsightly appearance.

In order to solve these problems, the present applicant proposed in Utility Application No. 109913/1987 a light emitting element that emits light of a predetermined wavelength at the bottom of a display panel consisting of a flat display element, and a light emitting element that emits light of a predetermined wavelength. A light receiving element is arranged to receive the reflected light when it is reflected by an object above the display panel and convert it into an electrical signal.
A panel switch is disclosed that controls a controlled device using the electrical signal.

This technology is preferable because the touch surface of the panel becomes flat and it can exhibit an excellent appearance, but in this panel switch, there are many infrared light emitting elements that normally emit infrared light as light emitting elements. When a liquid crystal display element is used as a flat display element, the liquid crystal display element itself and the polarizing plate attached to it have a transmittance of about 90%, but the transmittance of the liquid crystal display element itself and the polarizing plate attached to it is about 90%. The transmittance of the reflector or transmissive plate for infrared light is extremely low, less than 10%, so when you touch your finger in a predetermined position, the amount of infrared light that enters the light receiving element is small, making it difficult to detect. is difficult and tends to be unstable. Therefore, it is necessary to increase the sensitivity of the light-receiving element and the amount of light emitted by the light-emitting element.
Touch detection becomes uncertain and unstable, resulting in an increase in malfunctions, and if you try to increase the amount of light emitted by the light emitting element, power consumption increases and battery life is shortened. Nakatsuta.

[Purpose of invention]

In view of the above points, the present invention is a reflective panel switch using a display panel made of a liquid crystal display element, which can perform touch detection reliably and stably even in the case of infrared light. is intended to provide.

[Means and actions for solving problems]

The above object, according to the present invention, includes a display panel consisting of a liquid crystal display element having at least one display part, and one display panel arranged for each display part of the liquid crystal display element in the lower part of the display panel. The infrared light emitted from the infrared light emitting elements that emit infrared light and the paired infrared light emitting elements arranged one for each infrared light emitting element at the bottom of the display panel is used to display the above display. It includes an infrared light receiving element that receives the reflected light and converts it into an electrical signal when it is reflected by an object above the panel, and a controlled device that is controlled by the electrical signal from each light receiving element. A reflective plate or a transmissive plate disposed on the back surface of a liquid crystal display element constituting a panel has a transparent part in a region facing each display part of the liquid crystal display element through which the infrared light should pass. The light-transmitting part of this reflective plate or transmissive plate is formed by a large number of mesh-shaped holes, or is formed by printing a predetermined pattern in multiple colors on a transparent plate material. This is achieved by a panel switch that is formed by leaving a predetermined portion of the plate transparent in a mesh-like manner without applying the above-described printing.

According to this invention, various displays on the panel switch are performed by each display section of the liquid crystal display element according to its driving state, so a larger display can be obtained compared to conventional ones, and the display can be displayed on the reflector or transmissive plate. Since the provided transparent part is formed in a mesh shape,
The infrared light-emitting element and the infrared light-receiving element are difficult to see through the liquid crystal display element, so the display panel section provides an extremely highly visible display. , the infrared light emitted from the light emitting element passes through the transparent part provided on the reflective plate or transmissive plate of the display panel section, passes through the liquid crystal display element, is reflected by a reflective object, for example, the surface of a finger, and is reflected again on the liquid crystal display. By transmitting through the element and reaching the light receiving element without much reduction in the amount of light, the light receiving element can reliably and stably detect the touch of the finger, and thus the switch operation can be performed easily. Further, by switching the driving state of the display unit in accordance with this detection operation, a display can be performed in accordance with the switch operation. Moreover, this allows the amount of light emitted by the light-emitting element to be relatively small and the sensitivity of the light-receiving element to be relatively low, which reduces power consumption and extends battery life, especially in the case of battery-powered equipment. A panel switch suitable for handheld word processors, handheld personal computers, various remote control devices, etc. can be provided.

〔Example〕

The present invention will be described below based on embodiments shown in the drawings.

FIG. 1 shows an embodiment of a panel switch according to the present invention, and this panel switch 10 includes a liquid crystal display element 11 constituting a display panel, a protective transparent panel 12 provided on its upper surface, and It includes a transparent plate 13 disposed on the lower surface of the liquid crystal display element 11.

The liquid crystal display element 11 has at least one display section 1
1a, and for example, as shown in Figure 2, the lower level is equipped with a television, video deck, FM tuner,
Symbols related to AM tuners, CD players, VD players, etc. TV, VTR, FM, AM, CD, and VD are displayed, and the middle row shows a mark indicating the operation of the video deck, and the upper row shows the TV channel. A plurality of display units 11 are provided to display various characters and symbols such as numbers 1, 3, 4, 6, 8, and 10.
a is formed. Furthermore, the liquid crystal display element 1
A pair of infrared light emitting diodes (hereinafter referred to as infrared LEDs) 15 are mounted below the transparent plate 13 for each display section 11a of 1, respectively, on a substrate 14.
and infrared photodiode (hereinafter referred to as infrared PD)
16 are arranged.

The transparent plate 13 covers each display section 1 of the liquid crystal display element 11.
1a is provided with a mesh-shaped transparent part 13a having an appropriate shape and size for passing infrared light from each infrared LED 15 and infrared light incident on each infrared PD 16 as described later. (See Figure 3).

Here, a certain display section 11a of the liquid crystal display element 11
Referring to FIG. 4A, which shows the display section 11a,
111, which is always off (light shielded); an always-on (blank) section 112, which indicates the switch area; and a display section 113, which indicates a function that is turned on or off depending on the driving state (in the illustrated case, tape rewind display). The display pattern is composed of a display pattern having the following. On the other hand, in the case of the transparent plate 13 shown in FIG. 4B,
In the liquid crystal display element 11, a portion 132 corresponding to the display portion 112 of the display portion 11a is colored white, a portion 133 corresponding to the display portion 113 is colored green, and the other portion 131 is colored black to increase the contrast ratio. In addition, the infrared light from the infrared LED 15 and the reflected infrared PD
In the region through which the infrared light incident on 16 passes,
The light-transmitting portion 13a is formed by a large number of holes distributed in a mesh-like manner.

Note that the light-transmitting portion 13a does not have to be the holes distributed in the mesh shape as described above. For example, the light-transmitting plate 13 may be made of a transparent plate material, and the area of the light-transmitting portion 13a may be printed with multicolor printing as described above. Alternatively, it may be formed so as to remain transparent in a mesh shape.

Each infrared LED 15 is supplied with power from a power supply 17, and thereby each infrared LED 15 emits infrared light upward in the drawing of FIG. The light passes through the portion 13a and passes through each display portion 11a of the liquid crystal display element 11 and the transparent panel 12. Each infrared PD 16 converts the infrared light into an electrical signal when it receives light, and this electrical signal is input to a device to be controlled (not shown) via a sense amplifier 18, and is also input to a liquid crystal display element. The voltage is applied to drive each of the 11 display sections 11a.

Further, below the infrared LED 15 and the infrared PD 16 is an illumination light source 1 for back illumination of the liquid crystal display element 11.
The illumination light source 19 is a small one such as a fluorescent lamp or a cold cathode tube, and the illumination light source 19 is a small one such as a fluorescent lamp or a cold cathode tube, and irradiates light outside the infrared wavelength region and diffuses it through the transmissive plate 13. A liquid crystal display element 11 is back-illuminated uniformly.

The panel switch according to the present invention is constructed as described above, and the infrared light from the infrared LED 15 is
It passes through the mesh-shaped light-transmitting part 13a of the transmissive plate 13, passes through the corresponding display part 11a of the liquid crystal display element 11 and the transparent panel 12, and is irradiated upward, and although it does not normally return to the infrared PD 16, it is visible to the operator. However, the desired display portion 11a of the liquid crystal display element 11 is connected to the transparent panel 12.
For example, when a touch is made from above with a finger F, the infrared light from the infrared LED 15 corresponding to the display section 11a is reflected by the finger F and passes through the transparent panel 12 and the display section 11a of the liquid crystal display element 11 again. The light then passes through the transparent portion 13a of the transmissive plate 13 and enters the corresponding infrared PD 16.

At this time, the operator's finger F may be in contact with the transparent panel 12 as shown in the figure, but the infrared light
If an optical path is formed such that the infrared light from the LED 15 is reflected by the finger F and enters the infrared PD 16,
It does not necessarily have to be in contact with the transparent panel 12.

In this way, when the infrared light reflected by the finger F enters the infrared PD 16, it is converted into an electrical signal, and this electrical signal is amplified by the sense amplifier 18 and then supplied to the liquid crystal display element 11, for example, as shown in FIG. At this point, symbols such as TV and VTR indicating the type of object to be controlled are displayed on the lower display section 11a of the liquid crystal display element 11. In this state, for example, if you touch the surface of the transparent panel 12 where the VTR symbol is displayed with your finger F, the infrared light reflected by the finger F will enter the infrared PD 16 corresponding to the display section 11a. From this infrared PD16,
Electrical signals corresponding to the VTR are input to a video deck (not shown) and also to the liquid crystal display element 11, so that marks representing operations of the video deck are displayed on each display section 11a at the middle stage of the liquid crystal display element 11. Here, when playing the video deck, the display section 11a on which the play symbol is displayed
By touching the surface of the transparent panel 12 again, infrared light is incident on the corresponding infrared PD 16, and the video deck starts playing by the electric signal from this infrared PD 16. .

For example, in FIG. 2, the liquid crystal surface element 11
If you touch the surface of the transparent panel 12 in the part where the TV symbol is displayed in the lower display part 11a with your finger F, the electricity corresponding to TV from the infrared PD 16 corresponding to the display part 11a will be transmitted in the same way. When the signal is input to the TV, the liquid crystal display element 1
The upper display section 11a of 1 displays all the numbers 1, 3, 4, 6, 8, and 10 indicating channels, and the surface of the display section 11a that displays the number of the channel to be selected is a transparent panel 12. When you touch it from above, infrared light enters the corresponding infrared PD 16, and by converting the electrical signal from this infrared PD 16 into a remote control signal, the TV is tuned to the desired channel. .

[Effect of idea]

As described above, according to the present invention, an infrared light emitting element that emits a predetermined infrared light is disposed at the bottom of a display panel consisting of a liquid crystal display element having at least one display section, and When the infrared light emitted from the light emitting element is reflected by an object above the display panel, an infrared light emitting element receives the reflected light and converts it into an electrical signal, and an infrared light emitting element is controlled by the electrical signal from the light receiving element. A reflective plate or a transparent plate disposed on the back side of the liquid crystal display element constituting the display panel displays the red light in an area facing each display part of the liquid crystal display element. A light-transmitting part is provided in a portion through which external light should pass, and the light-transmitting part of this reflecting plate or transmissive plate is formed by a large number of holes provided in a meushu shape, or by forming a predetermined pattern on a transparent plate material. Since the panel switch is constructed in such a way that a predetermined portion of the reflective plate or transmissive plate is formed by multicolor printing and is held transparent in a mesh shape without applying the above printing, the panel switch is Various displays are performed by each display section of the liquid crystal display element depending on its driving state, so a larger display can be obtained compared to conventional ones, and the transparent section provided on the reflective plate or transmissive plate can be used as a mesh. Since the infrared light emitting element and the infrared light receiving element are difficult to see through the liquid crystal display element, the display panel section provides an extremely highly visible display, and each display section of the liquid crystal display element By simply touching the screen with your finger, the infrared light emitted from the light emitting element passes through the reflective plate or transmissive plate of the display panel, passes through the transparent part, passes through the liquid crystal display element, and is reflected on the surface of your finger. The light then passes through the liquid crystal display element again and reaches the light receiving element without much reduction in the amount of light. Therefore, the touch of a finger can be detected reliably and stably by the light-receiving element, and thus a switch operation can be performed easily.

Furthermore, by switching the driving state of the display section in accordance with the above-mentioned detection operation, it is possible to perform a display in accordance with the switch operation. Moreover, this allows the amount of light emitted by the light emitting element to be relatively small and the sensitivity of the light receiving element to be relatively low, so that power consumption can be reduced.

Therefore, according to the present invention, it is possible to provide a panel switch which has a long battery life, especially in the case of battery-powered equipment, and is suitable for handheld word processors, handheld personal computers, various remote control devices, and the like.

[Brief explanation of the drawing]

Fig. 1 is a schematic sectional view showing an embodiment of the panel switch according to the present invention, Fig. 2 is a plan view of a liquid crystal display element, Fig. 3 is an exploded perspective view showing a part of the panel switch, and Fig. 4A is a FIG. 4B is a partial plan view showing an example of the display pattern of one display section of the liquid crystal display element, and FIG. 4B is a partial plan view showing an example of the pattern of the transparent plate. 10...Panel switch, 11...Liquid crystal display element, 11a...Display section, 12...Transparent panel, 1
3...Transparent plate, 13a...Transparent part, 14...Substrate, 15...Infrared LED, 16...Infrared PD, 17
...Power source, 18...Sense amplifier, 19...Illumination light source, F...Finger.

Claims (1)

[Claims for Utility Model Registration] (1) A display panel consisting of a liquid crystal display element having at least one display part, and one display panel arranged for each display part of the liquid crystal display element at the bottom of the display panel. Infrared light emitted from an infrared light emitting element that emits a predetermined infrared light and a pair of infrared light emitting elements arranged one for each infrared light emitting element at the bottom of the display panel. It includes an infrared light receiving element that receives the reflected light and converts it into an electrical signal when it is reflected by an object above the display panel, and a controlled device that is controlled by the electrical signal from each light receiving element, and the above-mentioned A reflective plate or a transparent plate disposed on the back surface of the liquid crystal display element constituting the display panel has a mesh-like transparent plate in the area where the infrared light should pass in the area facing each display part of the liquid crystal display element. A panel switch characterized by being equipped with a light section. (2) The panel switch according to claim 1 of the utility model registration claim, wherein the light-transmitting portion of the reflector or transmissive plate is formed by a large number of mesh-shaped holes. . (3) The reflective plate or transmissive plate is constructed by printing a predetermined pattern in multiple colors on a transparent plate material, and the transparent part is kept transparent in a mesh shape without applying the above printing. A panel switch according to claim 1 of the utility model registration, characterized in that: