HK1022191B - Liquid crystal display - Google Patents

Description

Liquid crystal display device having a plurality of pixel electrodes

Technical Field

The present invention relates to a liquid crystal display device used as a display screen of various electronic devices such as a timepiece and a portable information device.

Background

Conventionally, timepieces that digitally display time information such as hour, minute, and second, and calendar information such as date, week, month, and year, by using a liquid crystal display, are mostly used for watches and clocks equipped with a quartz oscillation circuit.

There is also a combination timepiece in which an analog display for displaying time information by hands and a digital display for displaying time information or calendar information numerically or in characters are combined.

Further, an analog timepiece has been devised which has a dial constituted by a liquid crystal display panel, selectively displays various scale patterns, and analog-displays hands such as hour, minute, and second hands (see, for example, japanese patent laid-open No. 54-153066).

In addition to a timepiece, a small-sized reflection-type liquid crystal display device which consumes extremely small power is widely used as a display screen for displaying necessary information (character information or image information) in a mobile phone, a desktop computer, a portable game machine, and other various electronic devices.

A conventional liquid crystal display panel as such a liquid crystal display device is one in which a liquid crystal cell in which liquid crystal is sealed is sandwiched between two transparent substrates having electrodes on their respective inner surfaces, and an upper polarizing plate and a lower polarizing plate are disposed on both sides of the liquid crystal cell. Then, a voltage is applied between electrodes on a pair of substrates of the liquid crystal cell, and if an electric field is applied, the optical characteristics of the liquid crystal are changed, and the transmission and absorption of light incident on the liquid crystal display panel are partially controlled, thereby performing predetermined display.

The upper and lower polarizing plates are polarizing plates that absorb arbitrary linearly polarized light having a vibration plane orthogonal to the light transmission axis.

In a timepiece using such a conventional liquid crystal display, time information and calendar information are displayed in black on a white background in a normal white state.

However, the time information and the calendar information are displayed only on a white (bright) background in black (dark) as described above, and there is no change in the pattern, and the user is not interested in the time information and the calendar information. Therefore, in recent years, the consumption of digital display timepieces has decreased. In addition, a combination timepiece is not so popular, and an analog display timepiece using a liquid crystal display is not popular.

In other electronic devices, as well as liquid crystal displays, various kinds of information are generally displayed in black characters or images on a white background, and although there are also liquid crystal displays that display black and white in a reverse manner, they are still lacking in variety and lack in interest.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a liquid crystal display device which has a change in pattern and which can display information in various electronic devices such as a watch brightly and easily.

Disclosure of the invention

In order to achieve the above object, a liquid crystal display device according to the present invention includes: a liquid crystal cell in which liquid crystal is sealed between two transparent substrates having electrodes on opposite inner surfaces thereof; a first reflective polarizer disposed on an observation side of the liquid crystal cell; a second reflective polarizer disposed on an opposite side thereof; and a light absorbing sheet disposed on the opposite side of the liquid crystal cell with respect to the second reflective polarizing plate, wherein the first and second reflective polarizing plates reflect linearly polarized light having a plane of vibration orthogonal to the transmission axis.

In addition, a backlight may be provided instead of the light absorbing sheet. In this case, the transflective sheet may be disposed between the backlight and the second reflective polarizer.

Alternatively, a first reflection type polarizing plate may be disposed on the observation side of the liquid crystal cell, a second reflection type polarizing plate may be disposed on the opposite side, and an absorption type polarizing plate may be disposed on the observation side of the first reflection type polarizing plate, the absorption type polarizing plate being a polarizing plate that absorbs linearly polarized light having a vibration plane orthogonal to the transmission axis, the direction of the transmission axis being made to coincide with the direction of the transmission axis of the first reflection type polarizing plate.

In this case, the absorption polarizer may be a color polarizer that mainly absorbs light of a specific wavelength from linearly polarized light having a vibration plane perpendicular to the light transmission axis.

In addition, a light diffusion layer (light diffusion sheet) may be provided instead of the absorption-type polarizing plate.

In these liquid crystal display devices, the light absorbing sheet or the backlight may be disposed on the side opposite to the liquid crystal cell with respect to the second reflective polarizing plate.

In the case where a backlight is disposed, the transflective sheet may be disposed between the backlight and the second reflective polarizing plate.

In each of the above liquid crystal display devices, the first reflection type polarizing plate and the second reflection type polarizing plate are preferably arranged so that transmission axes thereof are perpendicular or parallel to each other.

The liquid crystal cell is sealed with liquid crystal for phase-modulating or intensity-modulating the transmitted linearly polarized light. The liquid crystal to be phase-modulated is a twisted nematic liquid crystal or a super twisted nematic liquid crystal, and the liquid crystal to be intensity-modulated is a guest-host liquid crystal.

In addition, the first reflection type polarizing plate is preferably disposed so that a transmission axis thereof is parallel to or perpendicular to a long axis direction of liquid crystal molecules on an observation side of the liquid crystal cell.

The liquid crystal display device of the present invention thus constituted can cause half of incident light from the observation side to be reflected by the first reflection type polarizing plate and the remaining half to be incident on the liquid crystal cell after passing through the first reflection type polarizing plate, and this part of light partially changes optical characteristics when passing through the liquid crystal cell, and a part totally reflected by the second reflection type polarizing plate and a part passing through it are formed, and metallic display can be performed.

By making the transmission axes of the first and second reflective polarizers at both sides of the liquid crystal cell perpendicular or parallel, or making the transmission axis of the first reflective polarizer parallel or perpendicular to the long axis direction of the liquid crystal molecules at the observation side of the liquid crystal cell, or by changing the kind of liquid crystal or the method of applying a voltage, it is possible to display the background portion and the displayed arbitrary portion with a metallic color by total reflection, display other portions with a dark color or an arbitrary color by the light absorbing sheet, display in a transparent state (the structure inside the device can be seen), or display with the color of the backlight or the like.

For example, the operation of a liquid crystal cell in which twisted nematic liquid crystal having a twist angle of 90 degrees is sealed is described by arranging first and second polarizers arranged above and below the liquid crystal cell so that their transmission axes are parallel to each other.

Half of the light incident from the viewing side (upper side) of the liquid crystal cell is reflected by the first reflective polarizer. The remaining half of the light enters the liquid crystal cell and passes through the liquid crystal cell, but the transmitted light is rotated by 90 degrees in the background portion where no voltage is applied to the liquid crystal of the liquid crystal cell, and therefore, the linearly polarized light having a vibration plane orthogonal to the transmission axis of the second reflection type polarizing plate is formed, and almost all of the linearly polarized light is reflected by the reflection type polarizing plate. Therefore, the background portion appears in a metallic tone (mirror-like).

On the other hand, since a voltage is applied to the liquid crystal of the display block portion of the liquid crystal cell, which displays various information such as time information and calendar information, the light transmitted through the liquid crystal cell does not rotate, and becomes linearly polarized light having a plane of vibration in the same direction as the transmission axis of the second reflection type polarizing plate, and is absorbed by the light absorbing sheet after passing through the reflection type polarizing plate. Therefore, the display block portion shows a dark color. However, if a colored light-absorbing sheet is used, only light of a specific color is reflected, and therefore, the light exits to the observation side along a path opposite to the above-described path, and is displayed in the color of the light-absorbing sheet. However, half of the incident light is reflected by the upper polarizing plate, so that the entire surface of the liquid crystal display panel is slightly in a metallic tone.

In addition, as described above, the display is reversed, the background portion can be displayed with the color of the light absorbing sheet, and the display block portion can be displayed with the metallic color.

Therefore, the liquid crystal display device of the present invention can display character information and image information in black on a white background with a more interesting display with a change in pattern.

In the liquid crystal display device of the present invention, since a backlight is disposed instead of the light absorbing sheet, it is possible to perform transmission type display at night or in a dark place.

If the semi-transmissive and semi-absorptive sheet is provided between the backlight and the polarizing plate adjacent thereto, it is possible to easily view both the transmissive display by the backlight and the reflective display by the external light.

Further, by disposing an absorption-type polarizing plate on the observation side of the first reflection-type polarizing plate disposed on the observation side of the liquid crystal cell of the liquid crystal display device and making the direction of the transmission axis of the absorption-type polarizing plate substantially coincide with the direction of the transmission axis of the first reflection-type polarizing plate, the amount of light emitted from the first reflection-type polarizing plate to the observation side and reflected from the entire surface can be reduced, the metallic feeling (gloss) of the entire surface can be suppressed, the display can be easily seen, and the viewing angle characteristics can be improved.

In this case, if a color polarizer that mainly absorbs light of a specific wavelength from linearly polarized light having a plane of vibration perpendicular to the light transmission axis is used as the absorption-type polarizer, the metallic feeling on the entire surface can be suppressed without much reduction in brightness.

Alternatively, a light scattering layer (light scattering sheet) may be provided outside the first reflection type polarizing plate, and instead of the absorption type polarizing plate, the light reflected from the entire surface of the first reflection type polarizing plate and the mirror-like reflected light of the information display portion by the second reflection type polarizing plate may be scattered, thereby suppressing a metallic feeling, enabling a soft display of a white color tone, facilitating a visual perception, and improving the viewing angle characteristics.

Brief description of the drawings

Fig. 1 is a schematic cross-sectional view showing the structure of a first embodiment of a liquid crystal display device of the present invention, and fig. 2 is an enlarged cross-sectional view showing the structure of a liquid crystal cell thereof.

Fig. 3 to 8 are schematic cross-sectional views showing the structures of second to seventh embodiments of the liquid crystal display device of the present invention, respectively.

Fig. 9 is an external perspective view of a quartz timepiece showing an application example of the liquid crystal display device of the present invention, and fig. 10 is a sectional view showing an internal structure thereof.

Best mode for carrying out the invention

Hereinafter, preferred embodiments of the liquid crystal display device according to the present invention will be described with reference to the drawings.

[ first embodiment: FIG. 1 and FIG. 2

First, a first embodiment of a liquid crystal display device according to the present invention will be described with reference to fig. 1 and 2.

Fig. 1 is a schematic cross-sectional view showing the structure of a liquid crystal display panel as the liquid crystal display device, in which the thicknesses and the intervals between the liquid crystal cell and each polarizing plate are enlarged.

The liquid crystal display panel 10 shown in fig. 1 is composed of a liquid crystal cell 11, a first reflection type polarizing plate 12 provided on the observation side (upper side in the figure) thereof, and a second reflection type polarizing plate 13 and a light absorbing sheet 14 provided on the side (lower side in the figure) opposite to the observation side of the liquid crystal cell 11.

As shown in fig. 2, a liquid crystal cell 11 hermetically seals a liquid crystal 3 between two glass substrates 1 and 2 with a sealing material 4, and the liquid crystal 3 uses, for example, a Twisted Nematic (TN) liquid crystal having a twist angle of 90 degrees or less.

Transparent electrodes 5 and 6 made of Indium Tin Oxide (ITO) are formed on the surfaces of the two glass substrates 1 and 2 that are in contact with the liquid crystal 3, respectively, and the surfaces in contact with the liquid crystal 3 are subjected to an alignment treatment so that the liquid crystal molecules are aligned in a predetermined direction.

By applying a voltage between the electrodes 5 and 6 of the liquid crystal cell 11, the alignment state of the liquid crystal 3 between the electrodes 5 and 6 is changed, and various information is displayed digitally or graphically.

The first reflection type polarizing plate 12 and the second reflection type polarizing plate 13 arranged vertically with the liquid crystal cell 11 interposed therebetween are arranged so that transmission axes thereof are parallel to each other.

The transmission axis of the first reflection type polarizer 12 is aligned (parallel) with the long axis direction of the liquid crystal molecules on the observation side of the liquid crystal cell 11.

The first and second reflective polarizers 12 and 13 are polarizers (reflective polarizers) that reflect arbitrary linearly polarized light having a vibration plane orthogonal to the light transmission axis. As such a reflective polarizer, for example, an optical film DBEF (trade name) manufactured by ミネソタマイニングアンドマニユフアクチヤリングカンパニ -et al of America is used. Available in japan from sumitomo スリ - エム.

The reflection type polarizing plate is developed by the above-mentioned manufacturing company, and is described in detail in Japanese patent application laid-open No. Hei 9-507308 (International publication No. WO95/17691) and Japanese patent application laid-open No. Hei 9-511844 (International publication No. WO 95/27919).

If the liquid crystal display panel of this embodiment is used, in fig. 1, half of the light incident from above the liquid crystal display panel 10 is reflected by the first reflective polarizer 12 and the other half is transmitted. Then, in the background portion for displaying character information or image information, since a voltage is not applied to the liquid crystal 3 of the liquid crystal cell 11, half of the transmitted light is rotated by 90 degrees when passing through the liquid crystal cell 11, becomes linearly polarized light having a vibration plane orthogonal to the transmission axis of the second reflection type polarizing plate 13, and is reflected by the second reflection type polarizing plate 13.

Therefore, almost all of the incident light is reflected at the background portion of the display information, and a metal-tone (mirror-like) display is obtained.

In the voltage applied display block portion of the liquid crystal cell 11 for displaying character information or image information, the light transmitted through the first reflection type polarizing plate 12 does not rotate when passing through the liquid crystal cell 11, and becomes linearly polarized light having a plane of vibration in the same direction as the transmission axis of the second reflection type polarizing plate 13, and therefore, the light passes through the second reflection type polarizing plate 13 and is absorbed by the light absorption sheet 14, and thus, black (dark) display is performed.

Further, if the light absorbing sheet 14 is colored so as to reflect only light components of a specific wavelength, various information can be displayed in an arbitrary color.

Therefore, compared with the conventional liquid crystal display panel in which time information, calendar information, and the like are digitally displayed in black (or dark) on a white (gray) background or various information is displayed, the liquid crystal display panel of the present invention can display an arbitrary color tone on a background of a metallic color tone, and therefore, can change a pattern, and can provide a fresh feeling and increase interest.

Further, if the first and second reflective polarizers 12 and 13 arranged vertically with the liquid crystal cell 11 interposed therebetween are arranged so that the transmission axes thereof are perpendicular to each other so as to match the twist angle of the liquid crystal 3, the light and shade of the background portion and the display block portion can be reversed, and various information can be displayed in the background portion of an arbitrary color tone with a mirror-like metallic color.

The light absorbing sheet 14 in fig. 1 is omitted, and the display block portion or the background portion which transmits half of the incident light can be made transparent, so that the internal structure of an electronic device such as a timepiece in which the liquid crystal display is mounted can be easily seen.

The present invention is not limited to application to a liquid crystal display panel in which electrodes 5 and 6 of liquid crystal cell 11 are formed on a plurality of partial patterns such as a partial pattern for digital display to perform digital display, and can be applied to a liquid crystal display panel in which electrodes 5 and 6 of liquid crystal cell 11 are formed in a dot matrix form to display various characters and patterns.

The liquid crystal sealed in the liquid crystal cell 11 is described by taking as an example the case of a Twisted Nematic (TN) liquid crystal that phase-modulates transmitted linearly polarized light, but a Super Twisted Nematic (STN) liquid crystal, a liquid crystal that intensity-modulates transmitted linearly polarized light, or the like may be used.

The guest-host liquid crystal is a mixed liquid crystal in which a liquid crystal is dissolved as a solvent and a dichroic dye is dissolved as a solute. Further, if an electric field is applied to the liquid crystal molecules to change the alignment state thereof, the alignment of the dichroic dye can be controlled along with the movement of the liquid crystal molecules, and the absorption of light incident from a certain direction can be modulated to perform display.

Therefore, if this guest-host liquid crystal is used as the liquid crystal 3 of the liquid crystal cell 11 in the liquid crystal display panel described above, the display portion in the background of the metallic tone can be easily colored.

Second to seventh embodiments: FIG. 3 to FIG. 8

Next, second to seventh ninth embodiments of the liquid crystal display device according to the present invention will be described with reference to fig. 3 and 8.

These drawings are schematic cross-sectional views similar to fig. 1 showing different structural examples of the liquid crystal display panel of the present invention, and the same parts as those in fig. 1 are denoted by the same reference numerals, and their description will be omitted.

Fig. 3 shows a structure of a liquid crystal display panel as a second embodiment of the liquid crystal display device of the present invention. In this liquid crystal display panel, as in the liquid crystal display panel 10 shown in fig. 1, a first reflection type polarizing plate 12 and a second reflection type polarizing plate 13, which are reflection type polarizing plates, are arranged vertically with a liquid crystal cell 11 interposed therebetween, but a backlight 15 is provided below the second reflection type polarizing plate 13 instead of the light absorption sheet 14.

As the backlight 15, an Electroluminescence (EL) element, a Light Emitting Diode (LED) element, a cold cathode tube, a hot cathode tube, or the like is used.

The display function of the liquid crystal display panel by external light is the same as that of the liquid crystal display panel 10 described above, but the light-transmitting portion can display by the surface color of the backlight 15 instead of the color of the light-absorbing sheet 14.

In addition, if the backlight 15 is caused to emit light when the external light is insufficient, the light is emitted to the observation side (upper side in fig. 3) through the light transmitting portion, and therefore, the display block portion and the background portion can be brightly displayed with the color emitted by the backlight 15.

Therefore, if a member capable of emitting red, green, yellow, or other color light is used for the backlight 15, or a member emitting white light and a color filter are used in combination, various color displays can be performed.

Fig. 4 shows a structure of a liquid crystal display panel as a third embodiment of the liquid crystal display device of the present invention. The liquid crystal display panel has the semi-transmissive and semi-absorptive sheet 16 disposed between the backlight 15 and the second reflective polarizer 13 adjacent thereto in the liquid crystal display panel shown in fig. 3.

With this configuration, the reflection display by the external light can be easily seen by the color of the scattered light of the semi-transmissive and semi-absorptive sheet 16. In the transmissive display by the backlight, the light emitted from the backlight 15 is diffused and softened when passing through the semi-transmissive and semi-absorptive sheet 16, and therefore, a display which is easy to see can be performed with the softened light.

Fig. 5 shows a structure of a liquid crystal display panel as a fourth embodiment of the liquid crystal display device of the present invention. In this liquid crystal display panel, an absorption-type polarizing plate 17 is disposed on the observation side of a first reflection-type polarizing plate 12 of a liquid crystal display panel 10 shown in fig. 1.

The absorption-type polarizing plate 17 is a normal polarizing plate that absorbs linearly polarized light having a plane of vibration perpendicular to the transmission axis, and is disposed so that the direction of the transmission axis thereof substantially coincides with the direction of the transmission axis of the first reflection-type polarizing plate 12.

If this liquid crystal display panel is used, since half of the incident external light is absorbed by the absorption-type polarizing plate 17 and the remaining half becomes linearly polarized light having a vibration plane in the same direction as the transmission axis thereof and is incident on the first reflection-type polarizing plate 12, most of it is not reflected but transmitted and is incident on the liquid crystal cell 11.

Then, since the light transmitted through the liquid crystal cell 11 in the portion rotated by 90 degrees is reflected by the second reflection type polarizing plate 13 and is emitted to the observation side along the path opposite to the above, the display can be made in a metallic tone, and the light transmitted through the liquid crystal cell 11 in the portion rotated (display block portion) is transmitted through the second reflection type polarizing plate 13.

Most of the light transmitted through the second reflective polarizer 13 is absorbed by the light absorbing sheet 14 (either a layer or a sheet) disposed below the second reflective polarizer and is not reflected to the observation side, so that the display block portion can be displayed in black or dark.

However, the light absorbing sheet 14 may be omitted, and in this case, the display block portion is transparent, so that the internal structure of the electronic device in which the liquid crystal display panel is mounted can be seen, and an interesting display can be performed. Alternatively, the light absorbing sheet may be provided on the side of the electronic device. Further, if a white sheet, a gray sheet, various coloring sheets (layers or sheets), or the like is disposed instead of the light absorbing sheet, information can be brightly displayed in full color in white, gray, or an arbitrary color clearly distinguished from the metal color of the background portion due to the diffuse reflection thereof.

In this embodiment, most of the light is reflected by the first reflective polarizing plate 12, so that the display becomes slightly darker, but the metallic feeling (gloss) of the entire surface of the display portion is suppressed, and the display can be easily seen, and the viewing angle characteristics can be improved.

Further, if a color polarizer that mainly absorbs light of a specific wavelength out of linearly polarized light having a plane of vibration perpendicular to the light transmission axis is used as the absorption-type polarizing plate 17, the metallic feeling (gloss) of the entire plane of the display portion can be suppressed without reducing the display luminance so much, display that is easy to see can be performed, and the viewing angle characteristics can be improved.

Fig. 6 shows a structure of a liquid crystal display panel as a fifth embodiment of the liquid crystal display device of the present invention. In this liquid crystal display panel, the light diffusion sheet 18 is provided on the observation side of the first reflection type polarizing plate 12 of the liquid crystal display panel shown in fig. 5 as a light diffusion (diffusion) layer in place of the absorption type polarizing plate 17.

The light diffusion sheet 18 is formed by: silica particles, which are silica particles, acrylic hollow particles, or calcium powder, is mixed into the binder, and the mixture is coated on a transparent film-like substrate. Or embossing the surface of the transparent film. The light scattering layer can also be formed by directly bonding such a film to the upper surface of the absorption-type polarizing plate 12 or by applying a light scattering agent.

With this configuration, the total reflection light by the first reflection type polarizing plate 12 and the specular reflection light by the second reflection type polarizing plate 13 can be scattered, the metallic feeling can be suppressed, soft and good display can be performed, and the viewing angle characteristic can be improved. However, the contrast of the display is somewhat reduced. Except for this, the same display function as that of the liquid crystal display panel shown in fig. 5 is provided.

In this liquid crystal display panel, as in the case of the fourth embodiment, the light absorbing sheet 14 may be omitted or provided on the electronic device side, and instead of the light absorbing sheet, a white sheet, a gray sheet, various coloring sheets (layers or sheets), or the like may be provided.

Fig. 7 shows a structure of a liquid crystal display panel as a sixth embodiment of the liquid crystal display device of the present invention. In this liquid crystal display panel, the semi-transmissive and semi-absorptive sheet 16 and the backlight 15 are provided on the side opposite to the observation side of the second reflective polarizing plate 13 (lower side in the figure) instead of the light-absorbing sheet 14 of the liquid crystal display panel shown in fig. 5. The transflective sheet 16 and the backlight 15 have the same structure as that described in the third embodiment shown in fig. 4.

With this configuration, it is possible to perform a reflective display by external light and a transmissive display by light emitted from the backlight 15, which are easy to see.

In addition, the transflective absorbing sheet 16 disposed between the backlight 15 and the second reflective polarizer 13 can be omitted.

Fig. 8 shows a structure of a liquid crystal display panel as a seventh embodiment of the liquid crystal display device of the present invention. In this liquid crystal display panel, as in the liquid crystal display panel shown in fig. 7, a semi-transmissive and semi-absorptive sheet 16 and a backlight 15 are provided on the side opposite to the viewing side of the second reflective polarizing plate 13 (lower side in the figure) instead of the light-absorptive sheet 14 of the liquid crystal display panel shown in fig. 6, and the display function is the same as that of the liquid crystal display panel shown in fig. 7.

Even in this case, the semi-transmissive and semi-absorptive sheet 16 disposed between the backlight 15 and the second reflective polarizing plate 13 can be omitted.

In these embodiments, various modifications described with respect to the first embodiment can be applied as well.

[ application example of liquid Crystal display device of the present invention ]

Here, an example of a quartz timepiece of a digital display system is shown, to which the liquid crystal display device of the present invention described above, i.e., the liquid crystal display screen is applied.

Fig. 9 is an external perspective view showing the quartz timepiece, and fig. 10 is a sectional view showing an internal structure thereof.

The quartz timepiece case 20 is constituted by joining a metal tube 21, a windshield glass 22, and a back cover 23.

The windshield glass 22 is made of a transparent material such as sapphire glass or a resin material, and is bonded to or fitted to the rear surface side of the tubular portion 21 with a spacer. Thus, the inside of the timepiece case 20 becomes an airtight structure into which dust and moisture do not enter.

A reflective liquid crystal display panel (liquid crystal display device) 10 of the present invention is provided on the windshield glass 22 side in the timepiece case 20 as a display portion for displaying time and the like.

On the liquid crystal display panel 10, there are a time display section 10a for displaying time, minute, and second, a calendar display section 10b for displaying month, day, and week, and a sign display section 10c for displaying a colon flashing once per second. These display portions are formed by block patterns of transparent electrodes 5, 6 formed on the inner surfaces of glass substrates 1, 2 of a liquid crystal cell 11 shown in fig. 2.

Further, the display of the ordinary time display function of 12 hours or 24 hours, the alarm function, the stopwatch function, the timer function, and the like can be performed.

The display function is switched and the time is corrected by operating a plurality of operation switches 24 provided on the cylindrical portion 21 of the timepiece case 20. A spacer is provided between the operation switch 24 and the cylindrical portion 21, and dust and moisture can be prevented from entering the inside of the timepiece case 20.

As shown in fig. 10, the quartz timepiece interior is configured such that the liquid crystal display 10 and the circuit board 30 are disposed substantially in parallel in the timepiece case 20, and the battery 31 constituting the driving power source thereof is disposed on the rear cover 23 side of the circuit board 30.

A quartz resonator 32 having an oscillation frequency of 32.768Hz is mounted on the circuit board 30; and a semiconductor integrated circuit 33, on which a quartz oscillation circuit and a frequency dividing circuit for generating a predetermined signal by oscillating the quartz resonator are mounted, are mounted on the semiconductor integrated circuit 33; a drive circuit for driving the liquid crystal display panel 10; a Central Processing Unit (CPU) for overall control of the quartz timepiece, and the like.

The liquid crystal display panel 10 and the circuit board 30 are electrically connected by the zebra rubber 34 disposed therebetween. Further, in order to secure the conductive connection between the liquid crystal display panel 10 and the circuit substrate 30, the zebra rubber 34 is compressed in the thickness direction thereof.

The zebra rubber 34 is formed by forming conductive layers containing carbon or metal particles at a predetermined interval in a silicon rubber as an insulator, and each conductive layer is electrically connected in the thickness direction thereof and is insulated from an adjacent conductive layer. Connection terminal patterns are formed on the opposite surfaces of the liquid crystal display panel 10 and the circuit substrate 30 at the same pitch size, respectively, so that the upper and lower conductive portions and the insulating portion formed of the conductive layer of the zebra rubber 34 are alternately arranged correspondingly.

When this timepiece is used, external light enters from the windshield glass 22 side (viewing side), and the reflective liquid crystal display panel 10 can digitally display time information such as hour, minute, second, and the like, calendar information such as date, week, month, and year, and the like, in various states (dark, white, various colors, a state in which the internal structure of the timepiece can be seen through, and the like) inside the metal-colored background.

Alternatively, the time information, calendar information, and the like can be displayed in metallic tone by reversing the display states of the background portion and the information display portion.

Any of the liquid crystal displays described in the first to seventh embodiments above can be applied to the liquid crystal display 10.

However, when a liquid crystal display panel provided with the backlight 15 is mounted, the backlight can be turned on and transmission type display can be performed by pressing the operation switch 24.

Possibility of industrial utilization

As described above, the liquid crystal display device of the present invention can display various information in various states such as dark, white, various colors, and a state in which the internal structure of the timepiece can be seen through in the background portion of the mirror-like or softened metallic tone by the incidence of external light. The liquid crystal display device provided with the backlight can also perform transmission type display in a dark place.

Further, characters, numerals, figures, and the like representing various information can be displayed in metallic tone by reversing the display states of the background portion and the information display portion.

Therefore, the liquid crystal display device of the present invention can be applied to a digital display quartz clock and a display panel of various electronic devices such as a portable electronic device, and thus a novel and interesting electronic device having a graphic change can be provided.

Claims (19)

1. A liquid crystal display device characterized by comprising:

a liquid crystal cell in which liquid crystal is sealed between two transparent substrates having electrodes on opposite inner surfaces thereof; a first reflective polarizer disposed on an observation side of the liquid crystal cell; a second reflection type polarizing plate disposed on the side opposite to the observation side of the liquid crystal cell; and a light absorbing sheet disposed on the opposite side of the second reflection type polarizing plate from the liquid crystal cell

The first and second reflective polarizers are polarizers that reflect linearly polarized light having a plane of vibration perpendicular to the transmission axis.

2. The liquid crystal display device according to claim 1, wherein:

the first and second reflective polarizers are arranged such that transmission axes thereof are perpendicular to each other.

3. The liquid crystal display device according to claim 1, wherein:

the first and second reflective polarizers are arranged such that transmission axes thereof are parallel to each other.

4. The liquid crystal display device according to claim 1, wherein:

the liquid crystal cell is filled with liquid crystal for phase modulation or intensity modulation of transmitted linearly polarized light.

5. The liquid crystal display device according to claim 4, wherein:

the liquid crystal is a twisted nematic liquid crystal.

6. The liquid crystal display device according to claim 4, wherein:

the liquid crystal is a super twisted nematic liquid crystal.

7. The liquid crystal display device according to claim 4, wherein:

the liquid crystal is a guest-host type liquid crystal.

8. The liquid crystal display device according to claim 1, wherein:

the first reflection type polarizing plate is disposed so that a transmission axis thereof is parallel to or perpendicular to a long axis direction of liquid crystal molecules on an observation side of the liquid crystal cell.

9. A liquid crystal display device characterized by comprising:

a liquid crystal cell in which liquid crystal is sealed between two transparent substrates having electrodes on opposite inner surfaces thereof; a first reflective polarizer disposed on an observation side of the liquid crystal cell; a second reflection type polarizing plate disposed on the side opposite to the observation side of the liquid crystal cell; and a backlight disposed on the opposite side of the second reflection type polarizing plate from the liquid crystal cell

The first and second reflective polarizers are polarizers that reflect linearly polarized light having a plane of vibration perpendicular to the transmission axis.

10. The liquid crystal display device according to claim 9, wherein:

a semi-transmissive and semi-absorptive sheet is provided between the backlight and the second reflective polarizer.

11. A liquid crystal display device characterized by comprising:

a liquid crystal cell in which liquid crystal is sealed between two transparent substrates having electrodes on opposite inner surfaces thereof; a first reflective polarizer disposed on an observation side of the liquid crystal cell; a second reflection type polarizing plate disposed on the side opposite to the observation side of the liquid crystal cell; and an absorption-type polarizing plate disposed on the observation side of the first reflection-type polarizing plate, and

the first and second reflection type polarizers are polarizers which reflect linearly polarized light having a vibration plane orthogonal to the transmission axis,

the absorption-type polarizing plate is a polarizing plate that absorbs linearly polarized light having a vibration plane orthogonal to the light transmission axis, and is used for absorbing linearly polarized light

The direction of the transmission axis of the absorption-type polarizer is substantially coincident with the direction of the transmission axis of the first reflection-type polarizer.

12. The liquid crystal display device according to claim 11, wherein:

the absorption-type polarizing plate is a color polarizing plate that mainly absorbs light of a specific wavelength from linearly polarized light having a vibration plane perpendicular to a light transmission axis.

13. The liquid crystal display device according to claim 12, wherein:

the light absorbing sheet is disposed on the opposite side of the second reflection type polarizing plate from the liquid crystal cell.

14. The liquid crystal display device according to claim 12, wherein the dry:

the backlight is disposed on the opposite side of the second reflection type polarizing plate from the liquid crystal cell.

15. The liquid crystal display device according to claim 14, wherein:

a semi-transmissive and semi-absorptive sheet is provided between the backlight and the second reflective polarizer.

16. The liquid crystal display device according to claim 11, wherein:

the light absorbing sheet is disposed on the opposite side of the second reflection type polarizing plate from the liquid crystal cell.

17. The liquid crystal display device according to claim 11, wherein:

the backlight is disposed on the opposite side of the second reflection type polarizing plate from the liquid crystal cell.

18. The liquid crystal display device according to claim 17, wherein:

a semi-transmissive and semi-absorptive sheet is provided between the backlight and the second reflective polarizer.

19. A liquid crystal display device characterized by comprising:

a liquid crystal cell in which liquid crystal is sealed between two transparent substrates having electrodes on opposite inner surfaces thereof; a first reflective polarizer disposed on an observation side of the liquid crystal cell; a second reflection type polarizing plate disposed on the side opposite to the observation side of the liquid crystal cell; and a light diffusion layer disposed on the observation side of the first reflection type polarizer

The first and second reflective polarizers are polarizers that reflect linearly polarized light having a plane of vibration perpendicular to the transmission axis.