JPH04180475A - Liquid crystal view finder device - Google Patents

Abstract

PURPOSE:To save power consumption by detecting that a liquid crystal view finder device is not observed by a sensor and interrupting the power source of the driving circuit system of a liquid crystal panel or a back light system. CONSTITUTION:When a liquid crystal view finder device is used, it is necessary to put an eye 8 to a hood 1 of it and to observe it. Then, it is sensed by a sensor 9 with a ultrasonic wave, etc., that the eye of a human being is approaching. A power source control part 10 is actuated so that a liquid crystal panel 3 or a driving circuit system 5 of a back light system 4 may be actuated normally and an image within the view finder device is observed. Besides, when the eye of the human being is separated from the hood 1 and stops observation, the power source control part 10 interrupts a power source or switching- controls to a power saving circuit.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a liquid crystal viewfinder device ilK using a liquid crystal panel.

Conventional technologyLiquid crystal display devices (LCDs) have traditionally been used mainly in Fi watches and calculators, but new fields of application in the future include television receivers, video monitors, video projection systems, and viewfinder devices. Demand is increasing in the field of video displays, and in the field of large-capacity displays, such as larger screens and higher densities, such as display devices for computer terminals and laptop computers. In response to these demands, the so-called active matrix method, in which a nonlinear element (such as a thin film transistor) is installed for each element, is used as a liquid crystal driving method to achieve high definition, full color, and
The dormitory is equipped with high-quality liquid crystal display panels.

In the first case, the color LCD viewfinder is equipped with the above-mentioned active matrix method.It solves the problems that prevented the conventional CRT-type color viewfinder device from becoming widespread (for example, poor focus adjustment due to resolution). However, by taking advantage of the characteristics of liquid crystal panels, such as being smaller and lighter, ultra-compact high-density liquid crystal panels of approximately 1 inch in size have been developed and are beginning to be supplied to the market for use in video movies.

Hereinafter, an example of the conventional liquid crystal viewfinder device described above will be explained with reference to the drawings.

FIG. 2 is a sectional view of a conventional liquid crystal viewfinder device. In Figure 2, 1 is a hood for looking into, 2
Lens thread for Fi magnification observation, 3 liquid crystal panel, 4
A backlight system including a Fi light source and a drive circuit thread for driving the 5Fi liquid crystal spring A/3 are installed in the liquid crystal viewfinder-tortoise cabinet 6. 7 is a power supply/signal wiring for connecting the liquid crystal viewfinder device il to, for example, a video movie main body in which this device is installed.

TI with LCD viewfinder anodized as above
The operation of It will be explained below.

The light beam emitted from the light source of the backlight system 4 is condensed and transmitted through the liquid crystal display panel 3.

Multiple video signals and control signals are supplied to this transmitted light Fi drive circuit system 5, and an image is displayed on the liquid crystal panel 3 under the control of three liquid crystal V-types of each element in the liquid crystal spring. In order to observe the OF2 image in a magnified manner, it can be seen through the lens thread 2 and the lens thread 1 (for adjusting the focal length of the observing human eye B).

Problems to be Solved by the Invention However, in the above configuration, even when the LCD viewfinder device N is not in use, for example, when the video movie main unit is powered on, the backlight system 4 and the LCD panel remain unchanged. 3 and the drive circuit system 5 remain powered on. This is due to the fact that the conventional CRT type viewfinder device W could not display an image immediately after the power was turned on, so it was impossible to use it.

Currently, in LCD viewfinder devices, the backlight system consumes approximately 1 watt of power, and the sliding part of the LCD panel consumes approximately 0.1 watt of power; most of the power is consumed by the backlight system. There is. In addition to these power consumptions, the fP4 power consumption of the video movie itself ranges from about 3 watts during playback to about 6 watts during camera shooting, so it can be said that it accounts for a large portion of the power consumption of the LCD viewfinder device. . Moreover, since the viewfinder device is not always being looked into, it has the disadvantage that the usable time as a portable device is sacrificed due to the limited power supply.

The present invention is intended to solve these problems, and aims to reduce the power consumption of a liquid crystal viewfinder device depending on the usage situation.

Means to Solve the Problems In order to solve the above problems, the present invention includes an LCD viewfinder device wIFI, an LCD panel drive circuit and a backlight system, and a fine crystal viewfinder device &. This is because a sensor is provided to detect whether or not the drive circuit is off, and a control system is provided to turn off at least one of the drive circuit wt system and the backlight system, or to switch to a power save power circuit.

Operation The present invention has the nine configurations described above, and when the LCD viewfinder device is not looked into, the sensor detects this state and turns off the power of the LCD panel drive or backlight system or reduces power consumption. When you switch to the circuit that reduces the amount of light and look into the LCD viewfinder device, the sensor detects this state and switches to the regular display, allowing the backlight system and LCD panel to immediately display the image. , it becomes possible to reduce the power consumption to the minimum necessary depending on the usage situation.

EXAMPLE Below, 112fiA will be explained based on FIG. 131 regarding the most outstanding liquid crystal viewfinder device of the present invention.

In the figure, members #'i that are the same as those of the conventional hook are designated by the same reference numerals, and detailed explanations thereof will be omitted.

In Fig. 1, the sensor attached to the Slt hood l,
Reference numeral 10 denotes a power source for controlling the power switches of the driving circuit system 5 of the liquid crystal panel 3 and the backlight system 4.The operation of the liquid crystal viewfinder device configured as described above will be explained below.

When using a liquid crystal viewfinder device, it is necessary to put 18 on the hood l for observation. At that time, a sensor 9 uses ultrasound to detect that the human eye is approaching.
is detected and the power supply control 51 (
1 operation, and the image in the viewfinder device is observed. Furthermore, when the human eye stops observing the hood properly, the power control SLO turns off the power or switches to the power save mode #&.

Book 9 as above! According to the embodiment, the driving of the liquid crystal panel 3
It is equipped with a J circuit system 5 and a backlight system 4, and includes a liquid crystal viewfinder device [t-sensor that detects whether someone is looking into the camera or not. -9, and at least one of the drive circuit system 5 and the backlight system 4 is provided with a control system that switches to a power-saving power supply circuit or a power-saving power supply circuit that turns off the electric power switch. This makes it possible to reduce power consumption to .

In addition, in the above sudden collapse, in addition to the sensor 9 butterfly ultrasonic sensor 7, the infrared sensor that detects the presence of humans is also used as a food Kl! It may also be a contact sensor that detects touch.

Effects of the Invention As described above, according to the present invention, a drive circuit system and a backlight system for a liquid crystal panel are provided, a sensor is provided to detect not looking into the liquid crystal viewfinder device L#r, and the drive circuit system At least one of the backlight system and the backlight system should be switched to a sub-III system or a power-saving power supply circuit where the power switch can be turned off.ll1lIi
By providing the IL system, it is possible to reduce power consumption to the minimum necessary level depending on the usage situation.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a liquid crystal viewfinder device according to the present invention, and FIG. 2 is a IIIrr# diagram of a conventional liquid crystal viewfinder device. l...Hood, 2...Lens thread, 3--Liquid crystal panel, 4--Backlight system, 5...M11 winding thread, 6-'Fff Bi17), 9-* Sensor 110-
[#ill1millS. 9 Sensor Diagram 2

Claims (1)

[Claims] 1. A control system that is equipped with a drive circuit system and a backlight system for the liquid crystal panel, is provided with a sensor that detects when the LCD viewfinder device is not looked into, and that at least one of the drive circuit system and the backlight system can be turned off with a power switch. Alternatively, a liquid crystal viewfinder device characterized by having a control system that switches to a power-saving power supply circuit.