JPS58210982A - Liquid crystal display apparatus - Google Patents

Abstract

PURPOSE:A liquid crystal display apparatus, prepared by using a liquid crystal material containing a specific amount of a compound expressed by a specific structural formula, capable of maintaining well the opration margin even at a low voltage, and suitable for the time-sharing driving at the low voltage. CONSTITUTION:A liquid crystal display apparatus for driving at <=2V effective voltage prepared by using a liquid crystal material containing 2-15% compound expressed by the formula (the number of carbon atoms in R is 2-7). EFFECT:The liquid crystal display apparatus has improved display quality. USE:Dot matrixes, graphic display or TVs, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a liquid crystal display device for time-division driving, and particularly to a liquid crystal display device using a liquid crystal material suitable for low-voltage time-division driving.

Conventionally, static driving has been used as a driving method for liquid crystal display devices, but now time-division driving has become mainstream in order to accommodate a large amount of information. However, when time-division driving is performed, unlike static driving, driving must be performed within a certain range (hereinafter referred to as a margin). This margin becomes smaller as the time division becomes higher, resulting in poorer display quality. but,
Due to the large amount of information in dot matrix, graphics, television, etc., 1/16 duty,
It is necessary to drive at high time divisions such as 1/32 duty and 1/64 duty.

On the other hand, when looking at the liquid crystal material that determines most of the characteristics of a liquid crystal display device, assuming that it is driven at a certain constant voltage, the higher the duty, the lower the monthly charge for the voltage will be required. However, it is known that the lower the voltage of the material, the lower the margin, the higher the viscosity, and the slower the response speed. The factors that determine the margin include the voltage rise characteristic (γ), the voltage viewing angle characteristic (/\φ), and the temperature dependence of the voltage (MUT), but here we will consider the margin at a constant temperature, so we will focus on the temperature characteristic. I decide not to think about it.

Next, an example of margin reduction in a conventional liquid crystal display device will be described.

The characteristics and voltage when 30 inches are used are shown in Table 1 below.

The closer to 1 both γ and Δφ in Table 1 are, the better the characteristics are, so the closer this 15φ/γ is to 1, the better the characteristics are.
In this way, the lower the voltage, the more the characteristics deteriorate significantly.

In view of the above situation, an object of the present invention is to provide a liquid crystal display device using a liquid crystal material system that can reduce the decrease in margin at low voltages compared to the conventional one and can maintain sufficient margins even at low voltages. 5%, 10th person, 15%,
2 (The data for 1 hour with the addition of l is shown in the following table. The relationship between voltage and /Sφ/γ is shown in the second table. In the figure, a is the characteristic of Table 1, and b is the table of the present invention. This is the second characteristic.

In this way, when a material containing R<◇coo4CN is used, there is little deterioration in characteristics at low voltages, making it an effective material for use in time-division driving, and liquid crystal display devices using this material have a high operating margin. This has the effect of improving display quality.

BRIEF DESCRIPTION OF THE DRAWINGS The figure is a diagram showing the relationship between voltage and Δφ/γ in one embodiment of the present invention.

Claims (1)

[Claims] 1. A liquid crystal display device using a liquid crystal material containing 2 to 15 compounds having a prime number of 2 to 7.