JPH02220576A - Liquid crystal display device - Google Patents

Abstract

PURPOSE:To set an optimum visual angle freely by adjusting the visual angle in the best condition through a variable resistor of a variable range setting means in response to the reclining angle of a reclining sheet and controlling a voltage applied to the display device. CONSTITUTION:Variable resistors VR5, VR6 of a control circuit 10 are adjusted so that the visual angle is optimized at the maximum and minimum tilt angle positions on a reclining sheet. Thus, a prescribed bias voltage is applied to transistors(TRs) Q1, Q2 and a DC voltage is outputted at a connecting point among emitters of the TRs Q1 and Q2 and resistors R7 and R8. Since a rotary shaft of a reclining sheet is fitted to the variable resistor VR3, its slider is moved in response to the tilt angle, the DC voltage is extracted and fed to a video chroma processing circuit 1, which varies the brightness of the liquid crystal display device 2.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a liquid crystal display device suitable for being disposed on reclining seats of airplanes, passenger trains, etc.

[Summary of the invention]

The present invention relates to a liquid crystal display device suitable for being installed on a reclining seat of an airplane, a passenger train, etc. The present invention relates to a liquid crystal display device that is suitable for being installed on a reclining seat of an airplane, a passenger train, etc. control means for supplying a reclining angle detection signal to the liquid crystal display to change the applied voltage; variable range determining means for determining a variable range of the applied voltage supplied to the liquid crystal display; disposed within the control means; This allows the amount of change in angle to be set freely.

[Conventional technology]

Conventionally, display systems have been proposed in passenger transport aircraft, in which a flat display is attached to the back of the seat of an airplane, passenger train, etc., so that passengers in the rear seats can enjoy TV images or obtain necessary information. There is. A liquid crystal display is generally used as this flat display.

As is well known, this liquid crystal display has a permissible viewing angle range (
(directivity) is narrow, and image quality deteriorates significantly when the screen is viewed from an angular position outside the permissible viewing angle range. Since the front seat backrest is usually reclining, the viewing angle of the screen for rear seat passengers changes depending on the reclining angle of the front seat, which inevitably degrades the image quality.

In order to eliminate such disadvantages, the present applicant has previously disclosed Japanese Patent Application Laid-open No. 634
Japanese Patent No. 42387 proposed a liquid crystal display control circuit that can always provide a good image even if the inclination angle of a reclining seat changes.

This liquid crystal display control circuit will be briefly explained with reference to FIG. In Figure 4, the input color video signal is luminance/
Processed by the chroma processing circuit (1), the three primary colors red (R),
After being decoded into green (G) and blue (B) signals, they are supplied to the liquid crystal display (2). The brightness/chroma processing circuit (1) has control terminals TI and T2 for a brightness control input and a contrast control input. The outputs of the volumes VRI and VR2 connected to the brightness adjustment knob and contrast adjustment knob are sent to the brightness/chroma processing circuit (1) through adders (3) and (4). 11 terminals Tl and T2. Therefore, brightness and contrast can be adjusted by operating each knob.

The reclining angle signal that is the output of the reclining angle detection volume VR3 is sent to an adder (3).

(4) to the brightness and contrast control terminals TI and T2 in the brightness/chroma processing circuit (1).

As a result, even if the screen viewing angle changes depending on the reclining angle, the directivity of the liquid crystal display (2) can be automatically corrected according to the angle, so that the image quality does not deteriorate significantly. In addition, brightness adjustment knob and contrast) II
The addition ratio of each control by the adjustment knob and the control by reclining angle detection is determined by the resistors R1 and R2 and R3 and R.
4.

The above-mentioned reclining angle detection volume VR.

The beam is attached to the rotating shaft for reclining, and the liquid crystal display is attached to the backrest of the reclining seat. The configuration of this reclining angle detection means is shown in FIG. In Figure 5, a gear (6) is fitted onto the reclining rotating shaft (5), and a gear (7) meshing with this gear (6) is shown.
) to the reclining angle detection volume VR, axis (8
). Rotating shaft for Imasu Kleinink (5)
When rotates in the direction of the arrow, the gears (6) and (7) rotate, rotating the rotor of the reclining angle detection volume VR, and transmitting an electrical output corresponding to the inclination angle of the reclining seat to the reclining angle detection volume VR. , so this output voltage is connected to the resistor R
By supplying the light to the adders (3) and (4) via 2+R4, the brightness and contrast can be adjusted according to the reclining angle of inclination.

[Problem to be solved by the invention]

According to the conventional configuration explained in FIGS. 4 and 5 above,
This results in the following drawbacks.

(b) When setting the amount of change in the viewing angle with respect to the reclining angle, the operating angle of the volume VR must be mechanically changed.The amount of change in the viewing angle with respect to the reclining angle can be freely set. I can't do that.

(b) Depending on the type of liquid crystal display, for example, if a narrow viewing angle is obtained, the amount of change in the applied voltage must be increased, and variations in the viewing angle of the liquid crystal display cannot be sufficiently covered.

(d) The setting can be made for liquid crystal displays of the same model or a single liquid crystal display, but the maximum and minimum values of the volume VR3 differ for different types of liquid crystal displays, making it impossible to obtain a versatile detection means.

The present invention was developed in view of the drawbacks of soft soil, and its purpose is to freely set the amount of change in the viewing angle by setting the optimal viewing angle at the maximum when the reclining seat is raised or reclined. The purpose of the present invention is to obtain a liquid crystal display device that can be used.

[Means to solve the problem]

The liquid crystal display device of the present invention, as shown in FIG. ,
and a control means (10) for supplying the reclining angle detection signal from the detection means VR to the liquid crystal display (2) to change the applied voltage, and a variable range of the applied voltage supplied to the liquid crystal display (2). Variable range determining means VR, , VR, for determining the variable range determination means VR, , VR, are disposed within the control means (10).

[Effect]

According to the liquid crystal display device of the present invention, the control means (10
) The viewing angle of the liquid crystal display when the reclining seat is reclined and raised is adjusted to the best using the variable range setting means V Rs, V Rb's volumes VR, , VR&, and this adjusted range is used for reclining angle detection. The volume VR, and the volume VR, depending on the clinching.

Since it is designed to move within the voltage difference range of VR, you can view the liquid crystal display in the optimal state at any reclining angle.

〔Example〕

A first embodiment of the liquid crystal display device of the present invention will be described below.
A description will be given of FIGS. 3 to 3.

FIG. 1 shows the control circuit of the liquid crystal display device of this example, and corresponding parts to those in FIG. 4 are given the same reference numerals and redundant explanation will be omitted.

In Figure 1, the video/chroma processing circuit (1) used in this example is configured so that the brightness changes depending on the DC voltage, and the contrast can be adjusted in the same way. The description will be made assuming that it has only the terminal TI.

The volume VR is disposed near the liquid crystal display (2) so that the user can directly rotate it to finely adjust the brightness, that is, the viewing angle. One end of the stator of this volume VR is connected to a voltage source Vcc,
The other end is connected to ground potential via a resistor R11. The movable element of this volume R4 is grounded through a series circuit of resistor R3, volume VR, and resistor R1, and is also grounded through a series circuit of resistor Rq, volume VR, and resistor R5. Also this volume VR4
The movable elements of transistors Q and Q! , and the bases of the transistors Q and Q are connected to the movable elements of the volumes V Rs and V Rb described above. The respective emitters of the second class transistors Q and Q2 are grounded via resistors R1 and R, and a volume v for reclining angle detection is connected between both emitters.
Connect one end and the other end of R3, respectively, and set the volume VR
The movable element No. 3 is connected to the brightness control terminal T1 of the video/chroma processing circuit (1). The volume VR for detecting the reclining angle is the reclining sea shown in Fig. 3).
(19) is attached to the reclining rotating shaft (5). As shown in Figure 3, the reclining seat (1
On the back of the backrest (20) of 9) is a liquid crystal display (
2) is fixed. In FIG. 3, when the reclining handle (21) is moved upward in the direction of the arrow, the reclining lever (22) rotates clockwise about the fulcrum (23) against the biasing force of the spring (24). The gear (25) disposed at the tip of the reclining lever disengages from the gear (26) fitted to the reclining rotation shaft (5), and the backrest (20) of the reclining seat (19) is always held in place. If the person sitting on this seat adjusts the reclining handle (21) to a predetermined angle with their back against the spring (27) biased in the direction of arrow E, the backrest will tilt to a predetermined angle and the gear (25) ) and gear (
26) are engaged and fixed. This reclining seat has a volume VR for reclining angle detection,
Although not shown, a volume VR may be attached in relation to this reclining rotation axis (5). Various mounting methods are conceivable; for example, it may be mounted as shown in FIG.

The operation of the liquid crystal display device of this example shown above is explained in the second example.
This will be explained using figures. Figure 2 is a liquid crystal display (2)
This figure shows a driving waveform for AC driving the counter electrode of the liquid crystal panel. Color video signals are alternately applied to opposing electrodes of the liquid crystal panel with opposite polarity at predetermined intervals around a reference line (11) of the AC signal, but only the driving waveform in the positive direction is shown in FIG. Color video signal (1
The brightness of the liquid crystal display (2) is changed by varying the level of the pedestal (13) in 2) with the volume VRs. First, volume VR, and volume V
R.

This is to adjust the viewing angle to the best condition when the beam-clining seat (19) is raised to the maximum and when it is folded down, and varies depending on the type of liquid crystal display (2).
For example, when the reclining seat is folded down, the brightness should be dimmed, and when it is raised up, the brightness should be brightened.Of course, the angle of inclination varies depending on the type of reclining seat, so the viewing angle will vary at the maximum and minimum inclination angle positions. When the position of the movable element with respect to the volumes VR, , VR is set in this way, a predetermined bias voltage is applied to the bases of the transistors QI and Qt, and the transistor Q is adjusted.

A DC voltage is output to each connection point between the emitter of Q2 and each of the resistors R, R1. As explained earlier, the volume VR3 is attached to the reclining rotation shaft (5) of the reclining seat (19), so
Volume VR according to the inclination angle of the reclining seat
, moves to the side of the DC voltage generated at the emitter of transistor Q or Q2, and within the range of the emitter voltage difference between transistors Q1 and Q, the DC voltage is taken out from the volume VR and used for video/chroma processing. The voltage is supplied to the control terminal T1 of the circuit (1), and the pedestal level (13) is varied by a voltage corresponding to the movement of the volume VR□, thereby changing the brightness of the liquid crystal display (2). The volume VR, is for fine adjustment of the viewing angle (brightness) for the user to make adjustments, and is usually located at the center position, but the maximum voltage value determined by the volume VR, and the minimum voltage value determined by the volume VR, are determined. Since the reclining angle can be shifted up and down while maintaining the same value, the viewing angle can be adjusted without changing the voltage range of the volume VR for reclining angle detection.

Since the liquid crystal display device of this example is configured and operates as described above, the optimal viewing angle can be set for each reclining seat when the reclining seat is raised and reclined, and the viewing angle can be adjusted according to the reclining within the voltage variable range. Since it is adjustable, you can view the image on the LCD display in the optimal condition at any reclining angle. In addition, since the user can set the standard value of the optimal viewing angle without changing the amount of change in the viewing angle with respect to the reclining angle, the image on the liquid crystal display (2) can be viewed in the optimal condition regardless of the sitting height. I can do it.

Incidentally, the present invention is not limited to the embodiments on the ridges, and can be modified in various ways without departing from the gist of the present invention.

You get what you can get.

[Brief explanation of the drawing]

Fig. 1 is a configuration diagram of a control circuit of the liquid crystal display of the present invention, Fig. 2 is a waveform explanatory diagram of the liquid crystal display of the present invention, Fig. 3 is a side view of main parts of the reclining seat of the present invention, and Fig. 4 is a conventional FIG. 5 is a block diagram of a conventional reclining angle detection means. (1) is a video/chroma processing circuit, (2) is a liquid crystal display, (5) is a rotating shaft for reclining, (10) is a control circuit, and (19) is a reclining seat. 〔Effect of the invention〕

Claims (1)

[Scope of Claims] A liquid crystal display disposed on the backrest of the reclining seat, a detection means for detecting the reclining angle of the reclining seat, and a reclining angle detection signal from the detection means being supplied to the liquid crystal display to apply a voltage. A liquid crystal display device comprising: a control means for changing the applied voltage; and a variable range determining means for determining a variable range of the applied voltage supplied to the liquid crystal display.