JPS6093546A - Handwriting input device - Google Patents

Abstract

PURPOSE:To obtain an inexpensive handwriting device superior in reliability by arranging an electromagnetic induction type opaque tablet under a liquid-crystal display body. CONSTITUTION:The liquid-crystal display body consists of a polarizing plate 1 which is about 200mum thick, glass substrates 2 and 3 are about 0.7mm., and a polarizing plates 4 and a reflecting plate 5 which are about 230mum, thick in total, and lines of magnetic flux generated by an exciting pen 7 are transmitted through the liquid-crystal display body. The tablet 8 is laminated under the liquid-crystal display body in one body. When aluminum foil which is about 15mum thick is used as the reflecting plate 5, the alternating magnetic field produced by the exciting pen 7 generates an eddy current in the aluminum foil and the magnetic field of the exciting pen 7 can not be detected by the opaque tablet 8. For the purpose, the insulating aluminum reflecting plate 5 is vapor-deposited to <=1mum to suppress the generation of the eddy current, and the magnetic field is detected by the tablet 8.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a handwriting input device such as a handwriting tablet that displays handwritten characters and the like on a liquid crystal display.

<Prior Art> A handwriting tablet using a conventional liquid crystal display is constructed as shown in FIG.

That is, a transparent tablet with leads made of a transparent conductive film or leads made of thin wires is formed on a liquid crystal display body consisting of a polarizing plate 1, two glass substrates 2 and 3 containing liquid crystal, a polarizing plate 4' and a reflecting plate 5. By handwriting input using an excitation pen 7 on the transparent tablet 6, the input is displayed on the liquid crystal display and confirmed via the transparent tablet 6. It is now possible to do so.

However, since such conventional handwriting tablets require the above-mentioned transparent tablet, they inevitably lead to higher costs and have problems in terms of reliability.

Purpose of the present invention The present invention has been made in view of the above-mentioned conventional problems, and its purpose is to reduce the cost by arranging an electromagnetic induction type opaque tablet under the liquid crystal display. The present invention aims to provide a handwriting input device with excellent reliability.

<Example> The present invention will be explained in detail below based on the drawings.

FIG. 2 is a side view of the device of the present invention. In the figure, 1 is a polarizing plate, 2 and 3 are glass substrates with liquid crystal sealed therein, 4 is a polarizing plate, and 5 is a reflecting plate, and these constitute a liquid crystal display.

In this liquid crystal display, the polarizing plate 1 has a thickness of about 200 μm, the glass substrates 2 and 3 have a thickness of about 0.7 μm, and the total thickness of the polarizing plate 4 and the reflecting plate is about 230 μm, and the lines of magnetic force caused by the excitation pen 7 have the above-mentioned configuration. It is considered that the light passes through the liquid crystal display.

If an aluminum foil with a thickness of about 15 μm, which is conventionally used in liquid crystal displays, is used as the reflector plate, the lines of magnetic force will not pass through it.
An AJ reflector with a diameter of less than μ is used.

Reference numeral 8 denotes an electromagnetic induction type opaque tablet similar to those conventionally used in personal computer digitizers, etc., and this tablet is laminated and integrated under the above-mentioned liquid crystal display.

In the handwriting tablet having such a configuration, by handwriting input on the liquid crystal display using the excitation pen 7, the input information is displayed on the liquid crystal display, and the magnetic field lines of the excitation pen 7 pass through the liquid crystal display. An electromagnetic induction type opaque tablet 8 is reached, and handwritten input can be made in the same way as with a conventional handwriting tablet.

Effects> As described above, since the handwriting input device of the present invention is constructed by laminating an electromagnetic induction type opaque tablet under the liquid crystal display, there is no need for a conventional transparent tablet, making it inexpensive and reliable. Therefore, it is possible to provide a handwriting input device with excellent performance.

[Brief explanation of drawings]

FIG. 1 is a side view of a conventional device, and FIG. 2 is a side view of the device of the present invention. 1 and 4 are polarizing plates, 2 and 3 are glass substrates, 5 is a reflective plate, 8 is an electromagnetic induction type tablet, agent: patent attorney
Aihiko Fukushi (and 2 others) Figure 1 Figure 2 Procedural amendment August 2Z, 1981 1, 1 (Indication of patent application 1982-201560 2. Name of the invention Handwritten input device 3. Amendment) Relationship with the case of the person who filed the patent application Patent applicant 4 agent address 7-22, Nagaike-cho, Abeno-ku, Osaka-shi, Kumo 545, Voluntary 7 Contents of amendment f+) The entire specification has been amended as shown in the attached sheet. (2) Add and edit Figure 3 as shown in the attached sheet. Description 1, Title of the Invention Handwritten Input Device 2, Claim 1 In an input device capable of inputting handwritten characters, etc. using a liquid crystal display, a magnetic induction type is provided below the electro-liquid crystal display. A handwriting input device characterized in that it is formed by laminating opaque tablets. 2 AI with a thickness of 1 μ or less as a reflective plate of the liquid crystal display
! The handwriting input device according to claim 1, characterized in that a reflective plate is used. 3. Technical field containing detailed description of the invention> The present invention is directed to the use of handwritten characters 9
A handwriting tablet using a conventional liquid crystal display, which can display figures etc. on a computer, etc., and also uses a liquid crystal display constituting an input panel, is constructed as shown in FIG. That is, on a liquid crystal display body consisting of a polarizing plate 1, two glass substrates 2 and 3 completely enclosing liquid crystal, a polarizing plate 4, and a reflecting plate 5, a transparent tablet with leads made of a transparent conductive film or leads made of thin wires is placed. By handwriting input using an excitation pen 7 on the transparent tablet 6, the input is displayed on the liquid crystal display and transmitted through the transparent tablet 6. It is now possible to check. However, conventional handwriting tablets require the above-mentioned transparent tablet, which inevitably leads to high costs, and the thickness of the transparent conductive film is very thin and is vulnerable to impact, so there is a problem in terms of reliability. was there. Purpose of the Invention The present invention is made in view of the above-mentioned conventional problems and is configured to provide a handwriting input device that is inexpensive and has excellent reliability. <Example> The present invention will be described in detail below based on the drawings. FIG. 2 is a side view of the device of the present invention. In the figure, 1 is a polarizing plate, 2 and 3 are glass substrates with liquid crystal sealed therein, 4 is a polarizing plate, and 5 is a reflecting plate, and these constitute a liquid crystal display. In this liquid crystal display, the polarizing plate 1 has a thickness of about 200 μm, the glass substrates 2 and 3 have a thickness of about 0.7 μm, the total thickness of the polarizing plate 4 and the reflecting plate 5 is about 230 μm, and the lines of magnetic force caused by the excitation pen 7 are It is designed to pass through the liquid crystal display of the structure. Reference numeral 8 denotes an electromagnetic induction type opaque tablet similar to those conventionally used in personal computer digitizers, etc., and this tablet is laminated and integrated under the above-mentioned liquid crystal display. If aluminum foil with a thickness of about 15 μm, which is conventionally used for liquid crystal displays, is used as the reflector plate 5, an eddy current will be generated in the aluminum foil by the alternating magnetic field generated from the excitation pen 7, and the opaque tablet 8 will It becomes impossible to detect the magnetism and field of the excitation pen 7. Therefore, in the present invention, by using an insulating A1 reflecting plate 5 formed by vapor deposition and having a thickness of 1 μm or less, the generation of the above-mentioned eddy current is suppressed and detection by the tablet 8 is made possible. Figure 3 shows the relationship between the thickness of the A1 reflector 5 and the transmittance of magnetic lines of force. All electromotive force was measured. In the figure, the mark is a reflector plate with aluminum vapor deposited on the film (002μ
023μ), Δ indicates aluminum vapor deposited on a glass plate (10μ to 2.5μ), and ○ indicates aluminum foil (10μ to 2.5μ).
50μ or more). Moreover, a - d are the frequencies of the rectangular waves applied to the excitation pen 7, and each a=50
KHz, b” 10 (IKI (z%C=200KHz
, d=800KHz k. According to the transmission characteristics of this magnetic field line, the aluminum film thickness is 1.0μ
If the film thickness is larger than , the transmittance (%) of the line of magnetic force tends to decrease significantly as the frequency applied to the excitation pen 7 increases;
It can be seen that with the film thickness below, the lines of magnetic force are transmitted through with virtually no loss. Therefore, according to the handwriting tablet configured as described above, by handwriting directly on the liquid crystal display using the excitation pen 7, the handwritten information can be displayed on the liquid crystal display. The lines of magnetic force pass through this liquid crystal display and reach the electromagnetic induction type opaque couplet (8), so handwritten information can be input in the same way as with conventional handwritten couplets. Note that in the above example, the transmittance of magnetic lines of force is increased by forming the AJ reflective film thinner, but the same effect can be achieved by reducing the electrical conductivity or magnetic permeability of the A1 reflective film. can. 71, QH < z-= 'r <Yu:, [1,・voice>> As described above, the handwriting input device of the present invention is constructed by laminating an electromagnetic induction type opaque tablet under the liquid crystal display. Therefore, the conventional transparent plate is no longer necessary, and an inexpensive and highly reliable handwriting input device can be provided. 4. Brief description of the drawings Figure 1 is a side view of the conventional device, Figure 2 is a side view of the device of the present invention, and Figure 3 is Aj? FIG. 3 is a diagram showing the relationship between the thickness of a reflecting plate and the transmittance of lines of magnetic force.

Claims (1)

[Scope of Claims] 1. An input device capable of inputting handwritten characters, etc. using a liquid crystal display. A handwriting input device comprising an electromagnetic induction type opaque tablet layered under a liquid crystal display. 2. AI with a thickness of about 1μ as a reflection plate of the liquid crystal display
! The handwriting input device according to claim 1, characterized in that a reflective plate is used.