JPS6279313A - Liquid crystal display apparatus - Google Patents

Abstract

PURPOSE:To ensure positive visual observation on the basis of novel monitor display, by providing a liquid crystal display panel consisting of a plurality of NCAP type liquid crystal display elements and a display circuit controlling the voltage applied to the display objective element. CONSTITUTION:A water level detection terminal 15 detects the water level of a basin 16 and inputs the water level signal 16 to a water level selection circuit 17 to select at what position of allotted water level L1-L6 the water level is while a liquid display circuit 7 selects a NCAP type liquid crystal display panel 5 to display said water level. Six display elements 5 and six switches 9 corresponding to the water level L are turned ON and the parts of the elements 5-1-5-3 on the display panel becomes transparent when the water level is L3 and the color of the back surface of the panel 5 becomes viewable from the front surface thereof. Therefore, positive visual observation can be performed on the basis of novel monitor display using a NCAP type liquid crystal.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a liquid crystal monitoring device, particularly a nematic linear aligned feeder (NEMAT).
ICCURVILINEARALIGNED PIIA
SE), abbreviated as NCAP).

[Background of the invention]

In water and sewage processes, monitoring panels are installed so that monitoring operators can understand the main flow of water and sewage processes (general pond configuration and water flow) and measured values at a glance, and can control anything. Set up. The main flow described above is called the graphic panel and colors it. Alternatively, zitong displays a combination of colored mosaics.

On the other hand, major process measurements currently use magnetic display elements called magsigns. An example is shown in FIG. Magsigns 2 are provided in a matrix on a top plate 1. This mag sign is a magnetic element whose front and back sides are painted in different colors. A magnetic material 4 is provided for each element, a coil 3 is wound around this magnetic material 4, and when a current is passed through the coil 3 and Control is performed so that the mag sign 2 becomes the front side 2A or the back side 2B depending on the case where there is no mag sign 2. FIG. 1 shows a diagram in which a 4×4 matrix is controlled so that the lower half 2×4 is 2B and the upper half 2×4 is 28. This combination of front and back allows the necessary display.

In this conventional example, it was not easy to control each magsign, and the cost was 1L.

On the other hand, the six types of liquid crystals that may be considered for use include the twisted nematic (TV) type and the nematic curved aligned phase (NCAP) type ("Liquid Crystal Display Technology of Tarik Co., Ltd.") 19
May 1985. (Published by Click).

TN-type displays utilize the characteristic that the polarization axis of incident light is twisted (dispersed) by the way the liquid crystals are arranged, and the basic structure is that the liquid crystal is sealed between two glass substrates, and two more glass substrates are placed between them. It is sandwiched between two polarizing plates. There are transparent electrode layers on the inner surfaces of the upper and lower glass substrates, and grooves are formed so that liquid crystal molecules are aligned in one direction. At this time, since the alignment directions of the upper and lower substrates are relatively shifted by 90@, the orientation of the liquid crystal molecules is twisted (twisted) by 906 between the substrates.

The polarization axes of the upper and lower polarizing plates are also rotated by 90° in accordance with the arrangement direction of the upper and lower glass substrates.

In the "OF F" state (no-voltage state S), light is polarized in one direction by the polarizing plate, passes through the glass substrate, and enters the liquid crystal layer. In the liquid crystal layer, the plane of polarization of the light is rotated by 90 degrees according to the alignment of the liquid crystal molecules, and the light is transmitted through the lower glass substrate and polarizing plate. Typically, there is a reflector behind the display, and the light is reflected back through the display. When viewed from the front side (incident light side), the display appears gray in this state (it appears relatively dark because more than 50% of the incident light is absorbed by the polarizing plate).

When an electric field is applied, the liquid crystal becomes erect. The electric field is generated by applying a voltage to the transparent conductive electrodes (transparent conductive thin films) attached to the inner surfaces of both glass substrates. In this state, the liquid crystal molecules change their alignment in the direction of the electric field, and the light is not rotated. Therefore, the light is directed toward the incident side. The light is polarized by the polarizing plate, passes through the liquid crystal layer without being rotated, and is completely blocked by the polarizing plate on the output side, whose polarization axis has been rotated by 90 degrees, so the display appears black.

The thickness of the liquid crystal layer has a large effect on the image quality of the display. If the liquid crystal layer is too thick, the response speed, viewing angle, contrast, etc. will be poor, and if it is too thin, unnecessary or undesirable miscellaneous colors will appear (this is caused by RAINBOW EFFE).
CT = called the rainbow effect).

Since TN type displays are sensitive to the thickness of the liquid crystal layer, it is difficult to produce large-sized displays of 5 to 100 square meters or more. This is because as the size of the display increases, it becomes difficult to make the thickness of the liquid crystal uniform over the entire display, and the possibility of forming a glass substrate also increases.

Furthermore, because of the glass structure of the TN type display, it is relatively heavy and is easily broken, and it is difficult to manufacture displays other than flat types such as curved displays, which is not cost-effective. Another disadvantage of TN type displays is the need for polarizers. Polarizing plates absorb light, darkening the screen and narrowing the viewing angle. This is especially noticeable in modern televisions and computer displays that use liquid crystals.

On the other hand, the NCAP type liquid crystal has a fundamentally different structure from the conventional TN type. That is, the liquid crystal is encapsulated in a transparent polymer and sandwiched between two plastic films with transparent electrode layers on the inside. ” OF
In the F'' state, the liquid crystals are arranged irregularly due to the compressive force of the capsule wall and disperse light. In this state, the liquid crystals are translucent and white, but colors can be added using dyes or colored light.

When a voltage is applied to the transparent electrode (transparent conductive thin layer) on the inner surface of the plastic film, an electric field is generated, and this force becomes greater than the surface force of the polymer capsule, causing the liquid crystal molecules to "stand up." In this state, light remains as it is. Because it passes through, the liquid crystal becomes transparent and the back side is visible.By placing a black back on the back side of the liquid crystal layer, a black and white display can be obtained (white display on a black background or black display on a white background).You can change the color of the back or use dyes. Colorization can be achieved by changing the color of the liquid crystal using colored light.

Conventionally, it has not been considered to apply such an NCAP type liquid crystal to a monitoring device.

[Purpose of the invention]

An object of the present invention is to provide a liquid crystal monitoring device using an NCAP type liquid crystal.

[Summary of the invention]

An object of the present invention is to use an NCAP type liquid crystal, and by applying a voltage, make the NCAP type liquid crystal transparent so that the color of the back side can be seen from the front of the panel, or to display using the property that when it is made opaque, it becomes white. Ta. At this time, a plurality of NCAP type liquid crystals were provided and their selection was controlled.

[Embodiments of the invention]

FIG. 2 shows an embodiment of a water level monitoring and display device for a pond (eg, a water treatment pond, a rock formation pond, etc.) in a water supply and sewage system. The pond 6 has assigned water levels L1 to L6, and a monitoring display device is installed for the purpose of displaying and monitoring which assigned water level the current water level is at.

A water level detection terminal 15 is provided in the pond 6, and a detection signal 16 from this terminal 15 is received by a water level selection circuit 17.

Select which position of the assigned water levels L1 to L6 the current water level is at.

The liquid crystal display circuit 7 takes in a signal 18 indicating the selection result, and sends an NCAP signal 18 to display the position indicating the selection result.
Select the type liquid crystal display board 5 to display the image.

The liquid crystal display board 5 has six display elements 5-1 to 5-6 corresponding to the assigned water levels L1 to L6. Display elements 5-1 to 5
-6 can be individually applied with the voltage of the power source 8. The selection means is the switch 9.

The liquid crystal display circuit 7 selects the switches 9 and turns on the switches 9 at the locations to be displayed.

FIG. 3 shows an example of a display on the liquid crystal display board 5. LCD display board 5
Under the condition that no voltage is applied, in which none of the elements 5-1 to 5-6 is selected, the color is white (opaque) as shown in the left figure. If the water level is now at L3, then the cables 5-1 to 5-3
, turn on the switches 9 for these three elements,
Apply voltage.

As a result, only the elements 5-1 to 5-3 are selected and made transparent, as shown in the right figure. This causes the water level to
It can be seen that it is in position 3.

When transparent, there are some ugly spots, so when it becomes transparent,
Just make it a special color. An example is shown in FIG. A painted plate 12 (a color plate may be used) painted with a special color is supported on the back surface of a display board 5 of a display device 10 by a support stand 11. When the elements of the display board 5 become transparent, the color of the painted board 12 can be seen from the front, allowing reliable visual inspection.

Each of the liquid crystal display elements 5-1 to 5-6 has a structure in which a transparent conductive plastic substrate is used as two electrodes, and a liquid crystal body made of liquid crystal encapsulated in a transparent polymer is sandwiched between them. Become.

A liquid crystal display element can display a single character if it is shaped like a character.

〔Effect of the invention〕

According to the present invention, a new monitoring display has become possible by using an NCAP type liquid crystal.

[Brief explanation of drawings]

FIG. 1 shows an embodiment of the present invention, FIG. 2 shows an example of its display, FIG. 3 shows an embodiment of the display device, and FIG. 4 shows a conventional example. 5... NCAP type liquid crystal display board, 6... Pond.

Claims (1)

[Claims] 1. A liquid crystal monitor consisting of a liquid crystal display board made up of a plurality of NCAP type liquid crystal display elements, and a display circuit that controls the application of voltage to the display target elements of the display elements of the display board. Device. 2. The liquid crystal monitoring device according to claim 1, further comprising a colored plate provided at a position opposite to the viewing side of the display element.