JPH03217822A - Back light type liquid crystal display device - Google Patents

Abstract

PURPOSE:To suppress wasteful electric power consumption and to effectively utilize light energy by integrating a reflecting plate which irregularly reflects the light from a back light source as a solar battery and storing the resulted electric energy in a charging cell. CONSTITUTION:Fluorescent tubes 14a, 14b are lighted to irradiate a screen 12 of the liquid crystal element from behind the screen and simultaneously display data is displayed on the screen 12 through a liquid crystal display driver 13 when the power source of a lap top computer mounted with the back light type liquid crystal display device 11 is turned on. The light energy at the time of the lighting of the fluorescent tubes 14a, 14b is converted to the electric energy by the reflecting plate 15 of the solar battery at all times and is stored in the charging cell 17. The fluorescent tubes 14a, 14b are put out and simultaneously the action to accumulate the energy in the charging cell 17 is stopped when the power source of the computer is turned off. The electric energy accumulated in the storage battery 17 is in turn utilized as the back up power source, etc., for the internal data of RAMs.

Description

[Detailed Description of the Invention] [Objective of the Invention] (Industrial Application Field) The present invention is directed to a backlight that is used as a display section of laptop-type office automation equipment, for example, and is a combination of a transmissive liquid crystal display section and a light source. type liquid crystal display device.

(Prior Art) Recently, backlight type liquid crystal display devices have been used as display units in various office automation equipment, including laptop personal computers and personal word processors.

This backlight type liquid crystal display device has a light source such as a fluorescent tube placed behind a transmissive liquid crystal display screen, and illuminates the display screen from behind so that the characters on the liquid crystal display appear clearly. In this backlight type liquid crystal display device, a diffused reflection plate is further arranged behind the light source so that light is uniformly irradiated over the entire surface of the liquid crystal display screen. It is configured as follows.

Here, the illuminance required by the above light source is on the rise as display screens become larger or color liquid crystals become available.
The power supply capacity for backlights is increasing.

(Problem 8 to be solved by the invention) However, if high illuminance or multiple light sources are provided just for the above-mentioned liquid crystal display screen, power consumption will not only increase, but also dispersion. It is not possible to make full use of the light energy.

The present invention was made in view of the above-mentioned problems, and it is an object of the present invention to fully utilize energy without wasting power consumption even when a high-intensity light source is installed as a backlight for a liquid crystal display screen, for example. The purpose of the present invention is to provide a backlight type liquid crystal display device that enables.

[Structure of the Invention] (Means for Solving the Problems) A backlight type liquid crystal display device according to the present invention includes a transmissive liquid crystal display section, a light source disposed behind the display screen of the liquid crystal display section, and a light source disposed behind the display screen of the liquid crystal display section. a solar cell reflecting plate disposed on a side of the light source opposite to the liquid crystal display section, which diffusely reflects the light from the light source in the direction of the liquid crystal display section and converts the light energy obtained from the light source into electric energy; , and a rechargeable battery that stores the electrical energy obtained by the solar cell reflector.

(Function) In other words, the reflector that diffusely reflects the light from the light source is integrated as a solar cell, and the electrical energy obtained thereby is stored in a rechargeable battery, which can be used as a back-up power source for internal memory, for example. It can be used.

(Example) An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows the side configuration of a backlight type liquid crystal display device. This backlight type liquid crystal display device is used, for example, in a laptop display section of a laptop computer, and includes a flat liquid crystal display section 11. ing. This liquid crystal display section 11 is composed of a transmissive liquid crystal element screen 12 constituting its display screen, and a liquid crystal display driver 13 that drives this liquid crystal element screen 12 according to the display data. Behind the liquid crystal element screen 12, two fluorescent tubes 14a, 1 are installed along the liquid crystal screen 12.
4b is arranged. These fluorescent tubes 14a, 14b illuminate the liquid crystal element screen 12 from behind and display the liquid crystal display characters on the screen 12 clearly. A solar cell reflecting plate 15 is disposed on the opposite side to the side.

The solar cell reflector 15 is integrally constructed using solar cells, and includes the fluorescent tubes 14a, . light 16a from 14b,
16b. ... uniformly and diffusely reflected in the direction of the liquid crystal element screen 12, and converts the light energy obtained from the fluorescent tubes 14a and 14b into electrical energy, and the photoelectric conversion action of the solar cell reflecting plate 15 The electrical energy obtained is supplied to and stored in the rechargeable battery 17. and,
The electrical energy stored in the rechargeable battery 17 is used as a backup power source for a memory such as a RAM.

That is, when the power is turned on to a computer equipped with a bar-nocrite type liquid crystal display device according to an embodiment of the present invention, the fluorescent tubes 14a and 14b of the liquid crystal display section 11 light up, and the liquid crystal micro-screen 12 is illuminated behind it. At the same time as irradiating from
Display data is displayed on the liquid crystal element screen 12 through a liquid crystal display driver 13. In this case, the fluorescent tubes 14a, 1
Light from 4b 16a. 16b is irradiated uniformly from the rear of the liquid crystal element screen 12 directly and diffusely reflected by the solar cell reflector 15, so that the characters displayed on the liquid crystal element screen 12 are clearly displayed on the entire surface thereof.

On the other hand, when the fluorescent tubes 14a and 14b are turned on when the laptop computer is powered on, the energy is constantly converted into electrical energy by the solar cell reflector 15 and stored in the rechargeable battery 17.

Then, when the power of the computer is turned off, the fluorescent tubes 14a and 14b turn off, and at the same time, the solar cell reflector 1
5, the storage of electrical energy to the rechargeable battery 17 is stopped, and the electrical energy stored by the rechargeable battery 17 is instead used as a backup power source for internal data for the RAM or as a power source for the CPU during standby. Become.

Therefore, according to the backlight type liquid crystal display device having the above configuration, the light from the fluorescent tubes 14a and 14b is not only used as a backlight for the liquid crystal element screen 12, but also converted into electrical energy by the solar cell reflector 15. Convert to rechargeable battery 1
7 and used as a backup power source for memory when the power is cut off, this is especially important as the display screen becomes larger and more colored.
If a larger number of fluorescent tubes 14a, 14b, .

[Effects of the Invention] As described above, according to the present invention, a transmissive liquid crystal display section,
A light source disposed behind the display screen of the liquid crystal display section, and a light source disposed on the opposite side of the light source from the liquid display section, which diffusely reflects the light from the light source toward the liquid crystal display section, and the light source A solar cell reflector that converts light energy obtained from the solar cell reflector into electrical energy, and a rechargeable battery that stores the electrical energy obtained by the solar cell reflector, and the electrical energy stored in the rechargeable battery is For example, by using it as a backup power source for the internal memory, even if a high-intensity fluorescent tube is installed as the light source, there will be no unnecessary power consumption, and the energy can be fully utilized. become.

[Brief explanation of drawings]

FIG. 1 is a side view of a backlight type liquid crystal display device according to an embodiment of the present invention.
...Liquid crystal display driver, 14a, 14b...fluorescent tube, 15...solar cell reflector, 16a, 16...light,
17... Rechargeable battery.

Claims (1)

[Scope of Claims] A transmissive liquid crystal display section, a light source disposed behind the display screen of the liquid crystal display section, and a light source disposed on the opposite side of the light source from the liquid crystal display section, which emits light from the light source. comprising a solar cell reflector that diffusely reflects light in the direction of the liquid crystal display and converts light energy obtained from the light source into electrical energy, and a rechargeable battery that stores the electrical energy obtained by the solar cell reflector; A backlight type liquid crystal display device characterized in that the above-mentioned reflector is integrated as a solar cell.