JPH1195199A - Liquid crystal display device with condensing mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the need for a light source, to reduce the electric power consumption and the size of a display device and to obtain a display device having good visibility while maintaining brightness by providing a liquid crystal display device with a beam-condensing function. SOLUTION: A lighting section consists of at least a light transmission part 2 corresponding to the display section 1 of the liquid crystal display device and a beam-condensing part 3 of an approximately semicircular shape in a longitudinal section connecting the light transmission part 2 and an optical path. The liquid crystal display device is irradiated with the light condensed by the beam-condensing part 3 from the light transmission part 2. Namely, the light transmission part 2 consists of an acrylic plate and the end thereof is formed as the beam-condensing part 3 constituted by processing the end to a lens of the approximately semicircular shape in the longitudinal section. A reflection plate 2a is formed on the rear surface side of the light transmission part 2 and a diffusion plate 2b is formed on the exit surface side thereof. These components are housed in an outside frame 10 and are united. More particularly the beam-condensing part 3 is exposed outside from a window bored at the outside frame 20 so that the external light is taken in. Then, the need for a light source is eliminated. In addition, the lighting is simultaneously executed for the purpose of visualization of a display screen while facing the display screen.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display (LCD) for performing display utilizing the electro-optical anisotropy of liquid crystal.
In particular, the present invention relates to a liquid crystal display device with a light-collecting mechanism, which has a light-collecting mechanism to reduce power consumption of a backlight.

[0002]

2. Description of the Related Art An LCD is constructed by sealing liquid crystal between electrode substrates having transparent electrodes formed on a transparent substrate. Since the liquid crystal has electro-optical anisotropy, by applying a desired voltage between the electrodes to form an electric field in the liquid crystal, the liquid crystal exhibits optical characteristics according to the electric field intensity. Therefore, by controlling the voltage for each pixel, a display image is created as an aggregate of pixels exhibiting a desired luminance. As described above, in the LCD, a display image is created by voltage control, and the LCD is small-sized,
It has advantages such as thinness and low power consumption, and has been put to practical use in fields such as OA equipment and AV equipment.

FIG. 10 shows the configuration of an LCD. (1) is an LCD panel, (11) is a light source, (12) is a light guide plate,
(13) is a reflection plate, (14) is a diffusion plate, and (15) is an outer frame holding these units. The light source (11) uses a fluorescent lamp or the like, and the light guide plate (12) uses an acrylic resin or the like. The light source (11), the light guide plate (12), the reflection plate (13), and the diffusion plate (14) constitute a backlight. Light emitted from the light source (11) is transmitted to the light guide plate (12), reflected by the reflector (13), and emitted to the LCD (1) as uniform plane light by the diffuser (14).

[0004]

Since a display screen created by the LCD (1) cannot be observed as an image by itself, as shown in FIG. 10, it is used integrally with a backlight. It is actually visualized in the form of the intensity distribution of the transmitted light. Therefore, the power used for the backlight is large, and the advantage of the low power consumption of the LCD itself has not been fully utilized.

[0005]

SUMMARY OF THE INVENTION The present invention has been made to solve this problem, and a liquid crystal is sealed between a pair of electrode substrates each having a predetermined electrode formed on a transparent substrate. A liquid crystal display device whose distribution is controlled so that the display screen is in a recognizable front state, and an illumination that is mostly installed behind the liquid crystal display device and collects ambient light to irradiate the liquid crystal display device with light. A liquid crystal display device with a light-collecting mechanism, in which a display screen in a front state recognizable by the liquid crystal display device is visualized, wherein the illuminating unit is a light guide corresponding to at least a display unit of the liquid crystal display device. A light section, a light collecting section having a substantially semicircular longitudinal section connecting the light guiding section and the light path, and the light condensed by the light collecting section is transmitted from the light guiding section to the liquid crystal display device. It is a configuration to be irradiated.

[0006] Since the light is collected by the condensing portion and the light is irradiated from the light guide portion to the liquid crystal display device, a light source is not required.
Power consumption is greatly reduced. In particular, the light condensing portion is configured to protrude in a plane from behind the liquid crystal display device. As a result, the light condensing portion that protrudes from the liquid crystal display device in a planar manner condenses the external light, so that the light is simultaneously emitted toward the display screen for visualization of the display screen.

In particular, the light condensing portion is formed in a lens shape by a light guiding material integrated with the light guiding portion. Accordingly, the light collecting unit and the light guide unit are integrally processed, and light loss between the light collecting unit and the light guide unit is eliminated, so that the light use efficiency is improved. In particular, the illuminator is separated from the liquid crystal display device, and ambient light incident on the gap is taken in by the illuminator.

Accordingly, not only the light condensing portion provided at the end of the illuminating portion but also the external light is directly incident on the light guiding portion, so that the amount of collected light is increased and a bright display screen is obtained. In particular, the illuminating section is configured to include a light source that connects the light guide section and an optical path. As a result, when a sufficiently bright display screen cannot be obtained only by condensing external light, a sufficiently bright display screen can be obtained by using a light source in combination.

[0009] In particular, the illuminating section is constituted by a light guide plate, and a mirror surface formed on the entire outer peripheral inner surface of the light guide plate except for the light exit surface and the light introducing section which is the light condensing section. Thus, the light incident on the light guide plate is held by the reflection inside the light guide plate, and is efficiently emitted from the irradiation surface. Further, a condensing portion formed by exposing the light guide plate is formed outside the liquid crystal display in a plan view.

In particular, the illuminating portion also serves as one of the electrode substrates of the liquid crystal display device, a portion corresponding to a display surface of the electrode substrate is the light guiding portion, and an end portion of the illuminating portion is processed with a lens to form the light collecting portion. The configuration is an optical unit. As a result, since the electrode substrate of the liquid crystal display device and the illuminating portion are also used,
Costs are reduced.

[0011]

FIG. 1 is a side sectional view of an LCD with a light collecting mechanism according to a first embodiment of the present invention. (1)
Denotes an LCD display unit, (2) denotes a light guide unit, and (3) denotes a light collecting unit. In the LCD (1), liquid crystal is sealed between a pair of electrode substrates each having a predetermined electrode formed on a transparent substrate, the transmittance is adjusted for each pixel by voltage control, a display image is created, and the display image is formed. It is in the state prepared in the previous stage. The light guide section (2) is made of an acrylic plate, and an end portion of the light guide section (3) is a condensing section (3) whose longitudinal section is lens-processed into a substantially semicircular shape. A reflection plate (2a) is formed on the back side of the light guide section (2), and a diffusion plate (2b) is formed on the emission surface side. These components are housed in an outer frame (10) and are unitized. In particular, the light-collecting unit (3) includes an outer frame (1).
It is configured to be exposed to the outside through a window opened in 0) and to take in external light.

Further, the light collecting part (3) may be a light collecting lens, and an optical path may be connected to the light guide part (2). Light collecting part (3)
The light collected in the step (1) is introduced into the light guide section (2), and is made into a uniform surface light source by reflection on the reflection plate (2a) and diffusion on the diffusion plate (2b). Irradiated, LC
The display image created in D (1) is made visible.

As described above, the LCD with the light condensing mechanism does not require a light source for the backlight, and the power consumption of the entire display device is greatly reduced. In particular, in order to obtain a brighter screen, the light from the sun behind the observer or indoor fluorescent lamps is collected by providing the light converging section (3) so as to protrude from the plane of the LCD (1). Therefore, it becomes possible for the observer to take light while heading to the LCD (1), and the display screen is visually recognized.

FIG. 2 is a side sectional view of an LCD with a light collecting mechanism according to a second embodiment of the present invention. In the present embodiment, a light source (4) is attached to the light guide section (2) together with the light collecting section (3). As the light source (4), a fluorescent lamp, EL, LED, N night light or the like is used. The light guide (2), the light collector (3) and the light source (4) are connected to an optical path. Accordingly, when the amount of light collected by the light-collecting unit (3) is not sufficient, such as when the light is cloudy outside the room or when the lighting is dark inside the room, the light source (4) is turned on to compensate for the irradiation light amount. Thus, a sufficiently bright display screen can be obtained. In addition, since the light source (4) is used supplementarily or only temporarily, power consumption can be reduced.

FIG. 3 is a side sectional view of an LCD with a light collecting mechanism according to a third embodiment of the present invention. In the present embodiment, the light source (5) such as a sheet-like EL lamp is used as the light guide (2).
Is formed entirely on the back surface of the substrate, and the irradiation light amount is increased. FIG. 4 is a side sectional view of an LCD with a light collecting mechanism according to a fourth embodiment of the present invention. In the present embodiment, the illuminating unit including the light guiding unit (2) and the condensing unit (3) is an LCD unit.
It is arranged away from (1). These LCDs
The space (10) is located between (1) and the illumination units (2, 3).
a) is secured and supported by the outer frame (10),
The outer frame (10) is a window (10b) leading to the space (10a) except for the supporting portion of the housing, and allows external light to enter the light guide (2). For this reason, since the light is directly collected by the light guide section (2), the amount of irradiation light is larger than in the case where the light is collected only by the light collecting section (3), and a brighter display screen is obtained. Further, the display screen can be observed even in a darker place.

FIG. 5 is a side sectional view of an LCD with a light collecting mechanism according to a fifth embodiment of the present invention. (6) is one electrode substrate of the LCD which also serves as a light guide portion, (7) is a light-collecting portion formed by processing an end of the electrode substrate (6), and (8) is opposed to the electrode substrate (6). This is a counter electrode substrate of the arranged LCD, and these electrode substrates are bonded together with a gap not shown in the figure, and a liquid crystal is sealed inside. The electrode substrate (6) is a glass substrate having a thickness of about 5 mm, and a reflection plate (9) whose inner surface on the back surface is processed into a mirror surface for irregular reflection is disposed. The counter electrode substrate (8) is a glass substrate of about 0.5 to 1 mm as in the related art.

In the present embodiment, the electrode substrate (6) is thick and also serves as a light guide plate, and the portion of the end protruding from the LCD section is processed into a lens to form a light collecting section (2). I have. That is, the electrode substrate, the light guide plate, and the condensing portion of the LCD are integrally formed on the same glass substrate, so that the cost is very low.

[0018]

FIG. 6 is a perspective view of an LCD with a light collecting mechanism according to a first embodiment of the present invention. Behind the LCD (1) (or the opposing electrode substrate (8)), an illuminating unit including a light guiding unit (2 (6)) and a light collecting unit (3 (7)) is provided. The illuminating part has a larger plane outer dimension by the condensing part (3 (7)), and protrudes around the display surface of the LCD (1 (8)), so that light from the observer side can be collected. It has been. That is, the light behind the observer, such as sunlight, indoor lighting, etc., is taken in the observation state, and the light is transmitted to the LCD (1).
And the display image created on the LCD (1) is visually recognized.

FIG. 7 is a perspective view of an LCD with a light collecting mechanism according to a second embodiment of the present invention. Light collector (3 (7))
Is the 4th of the LCD (1) (or the counter electrode substrate (8)).
And the outer dimensions of the illuminating portion (or the electrode substrate (6)) corresponding to the LCD (1) in four directions.
(8)). For this reason, the lighting area increases, the irradiation light amount increases, and a brighter display screen can be obtained.

FIG. 8 is a perspective view of an LCD with a light collecting mechanism according to a third embodiment of the present invention. The light condensing part (3 (7)) and the light source (4) are provided on four sides of the LCD (1) (or the counter electrode substrate (8)), and the light emitting part (or the electrode substrate (6)) is correspondingly provided. The external dimensions of the plane are
(7)) LCD (1)
(8)). For this reason, the lighting area becomes large and the light from the light source (4)
Since the irradiation light amount is further increased, a brighter display screen can be obtained.

In this embodiment, among the four sides of the LCD (1 (8)), one to three sides are used as a light source. Therefore, it is brighter than the case where only the light condensing mechanism is used, or the influence of environmental conditions is relatively small, and the power consumption is smaller than when only the light source is used. In addition, since the outer dimensions of the side where the light source (4) is provided do not increase, it is possible to prevent the entire apparatus from being enlarged.

FIG. 9 is a perspective view of an LCD with a light-gathering mechanism according to a fourth embodiment of the present invention. A condensing unit (3) and a light source (4) are provided on two opposite sides of the LCD (1). In this embodiment, the light-collecting unit (3) is provided on one side and the light source (4) is provided on another side, and the light-collecting unit (3 (7)) or the light source (4) is provided on four sides. LCD than
The width protruding from (1) is reduced, the external dimensions are reduced, and downsizing is realized. Further, since both the light condensing part (3) and the light source (4) are used, the amount of illumination light is large and a bright display screen can be obtained.

The present invention is not limited to the above-described embodiment, but includes one to four light-collecting portions (3) or a light-collecting portion on the same surface as the display surface of the LCD (1). It is characterized in that one to four (3) and one to three light sources (4) are provided. Accordingly, the power consumption is reduced by the light collecting mechanism, and the brightness is maintained by the light source. Thus, both low power consumption and brightness are achieved.

[0024]

As is apparent from the above description, the provision of the light condensing mechanism in the liquid crystal display device eliminates the need for a light source and reduces power consumption. In addition, by using a light-gathering mechanism and a light source together, brightness is maintained while reducing power consumption, and the light-gathering mechanism is prevented from becoming large, which prevents the device from being downsized. Was. Accordingly, low power consumption, miniaturization, and brightness of the display device were all realized, and a display device with extremely high visibility was obtained.

[Brief description of the drawings]

FIG. 1 is a side sectional view of an LCD with a light collecting mechanism according to a first embodiment of the present invention.

FIG. 2 is a side sectional view of an LCD with a light collecting mechanism according to a second embodiment of the present invention.

FIG. 3 is a side sectional view of an LCD with a light collecting mechanism according to a third embodiment of the present invention.

FIG. 4 is a side sectional view of an LCD with a light collecting mechanism according to a fourth embodiment of the present invention.

FIG. 5 is a side sectional view of an LCD with a light collecting mechanism according to a fifth embodiment of the present invention.

FIG. 6 is an LC with a light collecting mechanism according to the first embodiment of the present invention.
It is a perspective view of D.

FIG. 7 is an LC with a light collecting mechanism according to a second embodiment of the present invention.
It is a perspective view of D.

FIG. 8 is an LC with a light collecting mechanism according to a third embodiment of the present invention.
It is a perspective view of D.

FIG. 9 is an LC with a light collecting mechanism according to a fourth embodiment of the present invention.
It is a perspective view of D.

FIG. 10 is a configuration diagram of a conventional LCD.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 LCD 2 Light guide part 3,7 Condenser part 4,5 Light source 6 Electrode board and light guide part

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Atsushi Tanioka 2-5-5 Keihanhondori, Moriguchi-shi, Osaka Sanyo Electric Co., Ltd. (72) Makoto Shimizu 2-chome Keihanhondori, Moriguchi-shi, Osaka 5-5 Sanyo Electric Co., Ltd. (72) Yoshinori Kurahashi 2-5-5 Keihan Hondori, Moriguchi-shi, Osaka 2-5 Sanyo Electric Co., Ltd. (72) Inventor Tokuo Koma Keihanmoto, Moriguchi-shi, Osaka 2-5-5, Sanyo Electric Co., Ltd. (72) Inventor Ryuji Nishikawa 2-5-5, Keihanhondori, Moriguchi-shi, Osaka Sanyo Electric Co., Ltd.

Claims (7)

[Claims] 1. A liquid crystal display in which a liquid crystal is sealed between a pair of electrode substrates each having a predetermined electrode formed on a transparent substrate, the transmittance distribution of the liquid crystal is controlled, and the display screen is brought to a recognizable front state. A liquid crystal display device, which is mostly installed behind the liquid crystal display device, and has an illuminating unit that collects ambient light and irradiates the liquid crystal display device with light, and is placed in a front state recognizable by the liquid crystal display device. In the liquid crystal display device with a light condensing mechanism in which the display screen is visualized, the illuminating portion has a light guide portion corresponding to at least a display portion of the liquid crystal display device, and a longitudinal section connecting the light guide portion and an optical path is substantially half. A liquid crystal display device with a light-collecting mechanism, comprising a circular light-collecting portion, wherein the light condensed by the light-collecting portion is applied to the liquid crystal display device from the light guide portion. 2. The liquid crystal display device with a light condensing mechanism according to claim 1, wherein the light condensing portion protrudes from the back of the liquid crystal display device. 3. The liquid crystal display device with a light-condensing mechanism according to claim 1, wherein the light-condensing portion is formed in a lens shape by a light-guiding material integrated with the light-guiding portion. . 4. The collection according to claim 1, wherein the illuminating section is separated from the liquid crystal display device, and ambient light incident on the gap is taken in by the illuminating section. Liquid crystal display with light mechanism. 5. The liquid crystal display device with a light-collecting mechanism according to claim 1, wherein the illuminating unit has a light source connecting the light guide unit and an optical path. 6. The illumination unit according to claim 1, wherein the illuminating unit includes a light guide plate, and a mirror surface formed on an entire outer peripheral inner surface of the light guide plate except for a light exit surface and a light introduction unit serving as the light collecting unit. 3. The liquid crystal display device with a light collecting mechanism according to claim 1 or 2. 7. The illuminating section also serves as one electrode substrate of the liquid crystal display device, a portion corresponding to a display surface of the electrode substrate serves as the light guide section, and an end portion is formed in a lens shape. The liquid crystal display device with a light-condensing mechanism according to claim 1 or 2, wherein the liquid-crystal display device is a light-condensing portion.