JPS604209Y2 - Twisted nematic field effect liquid crystal display with illumination device - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a twisted nematic field effect liquid crystal display device with an illumination device.

In twisted nematic field effect liquid crystal display devices, the polarization axes of the upper and lower polarizers are perpendicular to each other, or
Depending on whether they are parallel, two types of display formats (ie, a black display format on a white background and a white display format on a black background) are possible.

When considering the above two types of display formats from the perspective of the viewer's recognition of the display pattern, when there is sufficient ambient light, black display on a white background has a higher recognition level than white display on a black background. On the other hand, when using a lighting device due to insufficient ambient light, displaying white on a black background is more effective in making the most of the lighting device's effects, resulting in a higher degree of recognition.

The present invention has been made in view of the above points, and in a twisted nematic field effect liquid crystal display device with an illumination device, the direction of the polarization axis of the upper and lower polarizing plates is adjusted in conjunction with the on/off operation of the illumination device. When the lighting device is on, the polarization axes of the upper and lower polarizing plates are parallel to each other, and when the lighting device is off, the polarization axes of the upper and lower polarizing plates are perpendicular to each other. By providing a means, a lighting device can always provide a highly recognizable display both when there is sufficient ambient light and when a lighting device is used when ambient light is insufficient. The present invention provides a twisted nematic field effect liquid crystal display device with a device.

Hereinafter, the present invention will be described in detail based on examples.

FIG. 1 is a block diagram showing the structure of an embodiment of the present invention.

In the figure, 1 is the upper polarizing plate, 2 is the upper polarizing plate angle (conductor), 3 is the upper polarizing plate angle handle, 4 is the liquid crystal cell, 5 is the lower polarizing plate, 6 is the light transmitting plate, and 7 is the scattering plate. board, 8 is lamp, 9
10 is a battery, 10 is a chassis (conductor), 11 is an upper polarizing plate angle holding part (insulator), and 12 is a lamp switch part.

One terminal of the lamp 8 is connected to the upper polarizing plate angle 2, the other terminal to the anode of the battery 9, and the cathode of the battery 9 to the chassis 10.

FIG. 2 is a sectional view showing the detailed structure of the lamp switch section 12.

In the figure, 2 is the upper polarizing plate angle (conductor), 3 is the upper polarizing plate angle handle, 10 is the chassis (conductor), 11 is the upper polarizing plate angle holding part (insulator), and 13 is the spring (conductor).
, 14 are balls (conductors).

The upper polarizing plate angle 2, the spring 13, and the ball 14 are electrically and mechanically connected.

3A, 3B and 3C are a plan view, a sectional view and a side view of the upper polarizing plate angle holding portion 11, respectively.

In the figure, reference numeral 15 denotes an opening formed in a part of the side surface of the upper polarizing plate angle holding part 11.

FIG. 4 is a plan view of the chassis 10.

In the figure, reference numeral 16 denotes a hollow portion in which the upper polarizing plate angle grip portion 3 is housed.

FIG. 5 is a diagram showing the relationship between the polarizing axes of the polarizing plate when the lamp is on, and FIG. 6 is a diagram showing the relationship between the polarizing axes of the polarizing plate when the lamp is off.

Hold the upper polarizing plate angle handle 3 and remove the upper polarizing plate angle 2.
, and the ball 14 is attached to the upper polarizing plate angle holding part 11.
When the ball 1 reaches the position of the opening 15 provided in the
4 fits into the opening 15 and comes into contact with the chassis 10.

This turns on the lamp 8.

At this time, the directions of the polarization axes of the upper and lower polarizing plates are parallel to each other as shown in FIG.

Therefore, when the lamp is lit, the display format is white on a black background.

On the other hand, when the lamp 8 is not lit, the state is as shown in FIG. 6, and the directions of the polarization axes of the upper and lower polarizing plates are perpendicular to each other.

Therefore, when there is sufficient ambient light and the lamp is off,
The display format is black on a white background.

In the above embodiment, the lower polarizing plate 5 is fixed and the upper polarizing plate 1 is rotatable, but it goes without saying that the upper polarizing plate 1 may be fixed and the lower polarizing plate 5 is rotatable.

As explained in detail above, according to the present invention, a display with a high degree of recognition is always displayed regardless of whether the ambient light is sufficient or when the ambient light is insufficient and a lighting device is used. Accordingly, it is possible to obtain a twisted nematic field effect type liquid crystal display device with an illumination device that can be used in various applications.

In addition, at least one of the upper and lower polarizing plates is attached to a disc-shaped polarizing plate angle and the polarizing plate angle can be rotated in the plane direction, so that the size and number of polarizing plates can be changed almost without changing from the conventional one. The polarization state can be changed freely without having to prepare a large space for arranging a polarizing plate.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram showing the configuration of an embodiment of the present invention, FIG. 2 is a sectional view showing the detailed configuration of the lamp switch section 12 shown in FIG. 1, and FIGS. 3 a, b, and C are respectively, the first
A plan view, a sectional view, and a side view of the upper polarizing plate angle holding part 11 shown in the figure, and FIG. 4 is a chassis 1 shown in FIG. 1.
5 is a diagram showing the relationship between the polarizing axes of the polarizing plate when the lamp is turned on in the embodiment shown in FIG. 1, and FIG. 6 is a diagram showing the relationship between the polarizing axes of the polarizing plate when the lamp is turned off FIG. Code 1: Upper polarizing plate, 2: Upper polarizing plate angle, 3: Upper polarizing plate angle handle, 4: Liquid crystal cell, 5: Lower polarizing plate, 6:
Light transmission plate, 7: Scattering plate, 8: Lamp, 9: Battery, 10:
Chassis, 11: Upper polarizing plate angle holding part, 12: Lamp switch part, 13: Spring, 14: Ball, 15: Opening part, 16: Hollow part.

Claims (1)

[Claims for Utility Model Registration] Twisted nematic field-effect liquid crystal with an illumination device comprising a twisted nematic liquid crystal cell containing twisted nematic ink liquid crystal, polarizing plates provided above and below, and an illumination body disposed behind it. In the display device, at least one of the polarizing plates is attached to a disc-shaped polarizing plate angle, and the polarizing plate angle is rotatable in a plane direction, and the upper and lower polarizing plates are rotated according to the rotation of the polarizing plate angle. A switch mechanism is provided that turns the illumination body on when the polarization axes are parallel to each other and turns off the illumination body when the polarization axes of the upper and lower polarizing plates are perpendicular to each other, and the illumination body has a white background when the illumination body is turned off and a black background when it is turned on. 1. A twisted nematic field effect liquid crystal display device with an illumination device, characterized in that the device is configured to display a display.