HK1022528A - Watch - Google Patents

Description

Clock and watch

Technical Field

The present invention relates to a timepiece (watch and clock) in which time information such as hour, minute, and second and calendar information such as date, week, and month are displayed on a liquid crystal display panel.

The timepiece includes, in addition to a timepiece that digitally displays time information and calendar information, a combination timepiece that is combined with an analog timepiece that displays time information with hands, and an analog timepiece that occasionally displays hands such as an hour hand, a minute hand, and a second hand by using a liquid crystal display panel to occasionally display scale marks of a dial plate.

Technical Field

Timepieces that digitally display time information such as time, minute, and second and calendar information such as date, week, month, and year on a liquid crystal display panel have been used in many cases in watches and clocks equipped with a quartz oscillation circuit.

In addition, there is also a combination timepiece in which an analog display of time information by hands and a digital display of time information and calendar information by numbers and characters are combined.

Further, there has been proposed an analog timepiece (see, for example, japanese patent laid-open No. s 54-153066) in which various scale patterns are selectively displayed when a dial is formed by a liquid crystal display panel, and hands such as an hour hand, a minute hand, and a second hand are displayed in an analog manner when the dial is formed by a liquid crystal display panel.

In such a timepiece, a conventional liquid crystal display panel for displaying time information and calendar information includes a liquid crystal cell in which liquid crystal is sealed, and an upper polarizing plate and a lower polarizing plate are disposed on both sides of the liquid crystal cell, which is sandwiched between 2 transparent substrates each having electrodes on the inner surfaces thereof facing each other. A voltage is applied between electrodes of a pair of substrates of a liquid crystal cell to generate an electric field, thereby changing optical characteristics of the liquid crystal, partially controlling transmission and absorption of light incident on the liquid crystal display panel, and performing predetermined display.

Either one of the upper and lower polarizing plates is a polarizing plate that absorbs linearly polarized light having a vibration plane perpendicular to the easy transmission axis.

In a timepiece using such a conventional liquid crystal display panel, time information or calendar information is displayed by displaying black on a white background in a general normal white mode.

However, if the time information or the calendar information is displayed only in such a manner that black is displayed on a white background, the appearance is not changed, and the user is not interested in the time information or the calendar information. Therefore, in recent years, the consumption of digital display watches has been drastically reduced. In addition, a combination timepiece is not so popular, and an analog display timepiece using a liquid crystal display panel is not yet popular.

The present invention has been made in view of such a situation, and an object thereof is to provide a timepiece capable of performing digital or analog display with a change in appearance image using a liquid crystal display panel.

Disclosure of the invention

In a timepiece including a liquid crystal display panel for displaying at least one of time information and calendar information, the liquid crystal display panel of the present invention has the following configuration in order to achieve the above object.

An absorption polarizer for absorbing linearly polarized light having a vibration plane perpendicular to an easy transmission axis is disposed on a viewing side of a liquid crystal cell in which liquid crystal is sealed between 2 transparent substrates each having an electrode on an inner surface facing each other, and a reflection polarizer for reflecting linearly polarized light having a vibration plane perpendicular to the easy transmission axis is disposed on an opposite side to the viewing side. A color filter is disposed on the viewing side of the absorptive polarizer or between the absorptive polarizer and the reflective polarizer.

Further, a light absorbing plate may be disposed on the opposite side of the liquid crystal display panel from the viewing side of the reflective polarizing plate. A light scattering plate may be disposed on the viewing side of the absorption polarizing plate. Alternatively, a backlight is disposed on the side opposite to the viewing side of the reflective polarizing plate. In this case, a semi-transmissive plate may be provided between the reflective polarizing plate and the backlight. The semi-transmissive plate may be an absorption polarizer.

In the liquid crystal display panel in which these backlights are arranged, a light scattering plate may be arranged on the viewing side of the absorption-type polarizing plate.

In the above-described various liquid crystal display panels, it is preferable that the easy transmission axis of the absorption polarizer disposed on the viewing side of the liquid crystal cell is parallel to the long axis direction of the viewing side liquid crystal molecules in the liquid crystal layer of the liquid crystal cell, and the easy transmission axis of the reflection polarizer is parallel to or perpendicular to the long axis direction of the viewing side liquid crystal molecules in the liquid crystal layer of the liquid crystal cell.

Alternatively, the easy transmission axis of the absorption polarizer disposed on the viewing side of the liquid crystal cell may be perpendicular to the long axis direction of the liquid crystal molecules on the viewing side in the liquid crystal layer of the liquid crystal cell, and the easy transmission axis of the reflection polarizer may be parallel to or perpendicular to the long axis direction of the liquid crystal molecules on the side opposite to the viewing side in the liquid crystal layer of the liquid crystal cell.

(these conditions are required particularly in the case of using a twisted nematic liquid crystal layer having a twist angle of 90 ℃ in a liquid crystal cell.)

As the color filter of the liquid crystal display panel, the following color filter can be used.

1) A selectively transmissive color filter that substantially transmits only light of a particular wavelength;

2) a color polarizing plate which transmits only light of a specific wavelength and absorbs light of other wavelengths while transmitting all linearly polarized light having a vibration plane perpendicular to the easy transmission axis;

3) and a dielectric multilayer film that reflects light of a specific wavelength among incident lights and transmits light of other wavelengths.

As the liquid crystal layer of the liquid crystal cell, any of a twisted nematic liquid crystal layer, a super twisted nematic liquid crystal layer, or a guest-host liquid crystal layer may be used.

The color filter of the liquid crystal display panel may be disposed on the viewing side of the absorption polarizer, between the absorption polarizer and the liquid crystal cell, or between the liquid crystal cell and the reflective polarizer. Alternatively, the color filter may be provided between a transparent substrate constituting the liquid crystal cell and the liquid crystal layer.

The watch of the present invention changes incident light from a viewing side into linearly polarized light by means of an absorption type polarizing plate, and changes the linearly polarized light into a twisted portion and an untwisted portion when the linearly polarized light is transmitted through a liquid crystal cell in a portion to which a voltage is applied and a portion to which no voltage is applied between liquid crystal cells of the liquid crystal display panel.

Further, since the color filter is provided in the light path, the color is changed. Therefore, the reflected portion is brought into a bright and colored metallic tone or mirror-glossy display state, and the incident light is brought into its ground color (the color of the components inside the timepiece, or any other color such as black or white in the case where a light absorbing plate or a semi-transmissive plate is provided) by the portion of the reflective polarizing plate through which the incident light passes, so that the time information or the calendar information can be brightly displayed in color by the contrast.

Therefore, it is possible to provide a digital display timepiece which is rich in variations in appearance and other various timepieces using a liquid crystal display.

Further, if the light scattering plate is disposed on the viewing side of the absorption polarizer of the liquid crystal display panel, the specular reflection light generated by the reflection polarizer is scattered, so that the display of the colored metallic tone or specular gloss becomes a soft tone and is easy to view, and the viewing angle can be widened.

When the backlight is provided on the viewing side of the reflective polarizing plate, even in a dark environment such as at night, by operating the backlight, half of the light incident on the reflective polarizing plate can be transmitted through the reflective polarizing plate, and can be made linearly polarized and incident on the liquid crystal cell. The linearly polarized light becomes a twisted portion and an untwisted portion depending on the presence or absence of a voltage applied between the electrodes of the liquid crystal cell, and the time information and calendar information can be vividly color-displayed by the light and shade between the portion transmitting through the absorbing type polarizing plate and the portion absorbed there and the colorization by the color filter.

Brief description of the drawings

Fig. 1 is a perspective view showing an example of an external appearance of a digital display type wristwatch according to the present invention, and fig. 2 is a sectional view showing an internal structure thereof.

Fig. 3 is a schematic cross-sectional view showing a 1 st configuration example of a liquid crystal display panel used in a timepiece according to the present invention, and fig. 4 and 5 are schematic cross-sectional views showing modifications thereof, respectively.

Fig. 6 is a schematic cross-sectional view showing the liquid crystal cell of fig. 3, with the middle part being cut away, and fig. 7 and 8 are cross-sectional views similar to fig. 6, each showing a different configuration of the liquid crystal cell provided with a color filter.

Fig. 9 is a schematic cross-sectional view showing a configuration of a liquid crystal display panel using the liquid crystal cell shown in fig. 7 and 8.

Fig. 10 and 11 are explanatory diagrams for explaining the principle of color display by the liquid crystal display panel shown in fig. 3.

Fig. 12 to 18 are schematic cross-sectional views showing configuration examples 2 to 8, respectively, of a liquid crystal display panel used in the timepiece of the invention.

Fig. 19 and 20 are explanatory views for explaining a principle of a 9 th configuration example of a liquid crystal display panel used in a timepiece of the present invention and a color display realized by the configuration example.

Fig. 21 and 22 are explanatory views for explaining a 10 th configuration example of a liquid crystal display panel used in a timepiece of the present invention and a principle of color display realized by using the same.

PREFERRED EMBODIMENTS

Hereinafter, preferred embodiments of the timepiece according to the invention will be described with reference to the drawings.

[ watch embodying the invention ]

First, the external appearance and the internal structure of a digital display type wristwatch according to the present invention will be described with reference to fig. 1 and 2.

The case 20 of the wristwatch is formed by joining a windshield 22 and a back cover 23 to a case 21 made of metal.

The windshield glass 22 is made of a transparent material such as sapphire glass, tempered glass, or a resin material, and is joined to the housing 21 by bonding or packing (packing) by fitting. The rear cover 23 is engaged to the rear side of the housing 21 by screwing or caulking.

This makes the case to have an airtight structure in which dust and moisture cannot intrude into the inside of case 20.

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

On the liquid crystal display panel 10, there are a time display section 10a for displaying time, minutes, and seconds, a calendar display section 10b for displaying month, day, and week, and a mark display section 10c for flashing a colon once per second.

In this way, it is possible to display a normal time display function of 12 hours or 24 hours, a calendar display function of month, day, and week, an alarm clock function, a stop watch function, a timer function, and the like.

The switching of the display function and the timing correction are performed by operating a plurality of operation switches 24 provided on case 21 of wristwatch case 20. The operation switch 24 is provided with a spacer between itself and the case 21 so that dust and moisture cannot intrude into the inside of the case 20.

As shown in fig. 11, the liquid crystal display panel 10 and the circuit board 30 are disposed substantially in parallel in the case 20, and the battery 31 constituting the driving power source is disposed on the rear cover 23 side of the circuit board 30.

A semiconductor integrated circuit 33 is mounted on the circuit substrate 30, and the semiconductor integrated circuit 33 is mounted thereon with: a quartz crystal 32 having an oscillation frequency of 32768Hz, a quartz oscillation circuit and a frequency dividing circuit for oscillating the quartz crystal 32 to generate a predetermined signal, a drive circuit for driving a liquid crystal display panel, and a Central Processing Unit (CPU) for performing overall control of the wristwatch.

The liquid crystal display panel 10 and the circuit board 30 are electrically connected with a zebra (zebra) rubber 34 disposed therebetween. In order to secure the electrical connection between the liquid crystal display panel 10 and the circuit board 30, the zebra rubber 34 is configured to be compressed in the thickness direction thereof.

The zebra rubber 34 is a rubber in which conductive layers containing carbon or metal particles are formed at a constant pitch in a silicone rubber as an insulator, and is electrically connected to adjacent conductive layers through the respective conductive layers in the thickness direction thereof, thereby being insulated from the adjacent conductive layers. The upper and lower conductive portions and the insulating portion formed by the conductive layer of the zebra rubber 34 are alternately arranged, and corresponding to this arrangement, connection terminal patterns are formed on the surfaces of the liquid crystal display panel 10 and the circuit board 30 facing each other at the same pitch size.

The configuration of the liquid crystal display panel 10 is explained in detail as follows.

[ 1 st configuration example of liquid crystal display Panel ]

First, a configuration example 1 of the liquid crystal display panel 10 used in the timepiece as described above according to the present invention will be described with reference to fig. 3 to 11. These drawings show the thickness and the interval of each constituent member in a greatly enlarged manner.

Fig. 3 is a schematic cross-sectional view showing the structure of the liquid crystal display panel 10, and fig. 6 is a schematic cross-sectional view showing the structure of the liquid crystal cell 12, cut at the middle part.

As shown in fig. 3, the liquid crystal display panel 10 includes a liquid crystal cell 12, an absorption polarizer 14 disposed on a side viewed by an observer (upper side in the drawing), a reflection polarizer 16 disposed on a side opposite to the viewing side of the liquid crystal cell 12 (lower side in the drawing), and a color filter 18 disposed between the absorption polarizer 14 and the liquid crystal cell 12.

As shown in fig. 6, the liquid crystal cell 12 is formed by bonding a pair of substrates 1 and 2 each made of a transparent insulating material such as glass to each other, disposing a sealing material 4 around the substrates, and sealing and sandwiching a liquid crystal layer 3 between the substrates. Transparent electrodes 5 and 6 made of Indium Tin Oxide (ITO) are formed on the inner surfaces of the pair of substrates 1 and 2 facing each other, and at least one of the electrodes is formed in a pattern (7-segment character pattern in the case of displaying numerals or the like) necessary for displaying time information or calendar information.

The liquid crystal layer 3 is composed of Twisted Nematic (TN) liquid crystal having a twist angle of 90 °. The side in contact with the liquid crystal layer 3 of each substrate 1, 2 and electrode 5, 6 is treated so that the liquid crystal molecules are aligned in a prescribed direction.

The reflective polarizing plate 16 provided on the side opposite to the viewing side of the liquid crystal cell 12 is a thin plate-like member that transmits linearly polarized light having a plane of vibration parallel to the easy transmission axis and reflects linearly polarized light having a plane of vibration perpendicular to the easy transmission axis. As the reflective polarizing plate 16, for example, an optical film DBEF (trade name) sold by sumitomo 3M co.

The easy transmission axis of the absorption polarizer 14 and the long axis direction of the liquid crystal molecules on the viewing side in the liquid crystal layer 3 of the liquid crystal cell 12 are arranged in parallel to each other.

The easy transmission axis of the reflective polarizer 16 and the long axis direction of the liquid crystal molecules on the side opposite to the viewing side in the liquid crystal layer 3 of the liquid crystal cell 12 are also arranged parallel to each other.

Therefore, the easy transmission axis of the absorption type polarizer 14 and the easy transmission axis of the reflection type polarizer 16 are perpendicular to each other.

In fig. 3, the stripes in the absorption polarizer 14 and the reflection polarizer 16 are oriented in the direction of the easy transmission axis, the horizontal stripes in the absorption polarizer 14 are oriented in the direction parallel to the paper surface, and the vertical stripes in the reflection polarizer 16 are oriented in the direction perpendicular to the paper surface.

The color filter 18 disposed between the absorption polarizer 14 and the liquid crystal cell 12 is a selective color filter (also called an absorption filter) that substantially transmits only light of a specific wavelength and absorbs light of other wavelengths. Therefore, the light transmitted through the color filter is colored to a specific color.

As the color filter of this selective type, for example, a pigment dispersion coating film in which a pigment is dispersed and mixed in an organic resin is used. Since the pigment dispersion coating film can be formed by a coating method or a printing method, a new constituent member is not required, and the pigment dispersion coating film can be coated and formed on one surface (in the example shown in fig. 3, the surface opposite to the viewing side of the absorption polarizing plate 14 or the surface outside the substrate 1 on the viewing side of the liquid crystal cell 12) of an existing constituent member. Of the light incident on the pigment dispersion coating film, only light of a specific wavelength is transmitted, and light of other wavelengths is absorbed.

The color filter 18 is not limited to the position shown in fig. 3, and may be disposed at any position closer to the viewing side than the reflective polarizer 16 constituting the liquid crystal display panel 10.

Therefore, as shown in fig. 4, the liquid crystal cell may be disposed on the viewing side (outside) of the absorption polarizer 14 or, as shown in fig. 5, between the liquid crystal cell 12 and the reflection polarizer 16.

Alternatively, as shown in fig. 7 or 8, the liquid crystal cell 12 may be a color filter-containing liquid crystal cell 12CF, and as shown in fig. 9, the liquid crystal display panel 10 may be configured by arranging only the absorption polarizer 14 and the reflection polarizer 16 on both sides of the color filter-containing liquid crystal cell 12 CF.

In this case, as shown in fig. 7, the color filter 18 may be formed by applying a pigment dispersion coating film to the inner surface of the substrate 1 on the viewing side of the liquid crystal cell 12CF, or as shown in fig. 8, the color filter 18 may be formed by applying a pigment dispersion coating film to the inner surface of the substrate 2 on the side opposite to the viewing side of the liquid crystal cell 12 CF.

Transparent electrodes 5 and 6 are formed on the surfaces of the color filters 18 which are in contact with the liquid crystal layer 3. However, the color filter 18 may be formed over the entire surface in contact with the liquid crystal layer 3 of the substrate 1 on which the electrode 5 is formed or over the entire surface in contact with the liquid crystal layer 3 of the substrate 2 on which the electrode 6 is formed.

The principle of color display by the liquid crystal display panel shown in fig. 3 will be described with reference to fig. 10 and 11.

In these figures, as described in fig. 3, the horizontal stripes in the absorption polarizer 14 and the vertical stripes in the reflection polarizer 16 respectively indicate that the easy transmission axis is parallel to the paper surface and perpendicular to the paper surface, the long solid line with an arrow at the tip end indicates light, the short solid line with an arrow at both ends indicates the direction of the vibration plane of linearly polarized light after passing through each component, the horizontal direction indicates parallel to the paper surface, and the vertical direction indicates perpendicular to the paper surface.

As described above, the liquid crystal layer 3 of the liquid crystal cell 12 is defined to be composed of TN liquid crystal having a twist angle of 90 °. Color filter 18 is defined as a selective transmission type color filter which transmits only yellow light and absorbs light other than yellow light.

Fig. 10 shows a background portion where no voltage (called OFF state) is applied between the electrodes 5, 6 of the liquid crystal cell 12, and in this portion, the vibration plane of the linearly polarized light transmitted through the liquid crystal cell 12 is twisted (phase-modulated) by 90 ° due to the twisting function of the liquid crystal layer 3 (fig. 6).

Fig. 11 shows a display portion of characters or the like in which a voltage (called ON state) is applied between the electrodes 5 and 6 of the liquid crystal cell 12, and in this portion, the liquid crystal layer 3 of the liquid crystal cell 12 does not have a twist function because of the liquid crystal molecules standing up, and linearly polarized light entering is transmitted without being twisted (phase modulation) in the direction of the vibration plane thereof.

Of the light incident on the liquid crystal display panel 10 from the viewing side (upper side in the drawing), half of the light is absorbed by the absorption polarizer 14, and the remaining half is transmitted through the absorption polarizer 14 and then becomes linearly polarized light having a vibration plane in a direction parallel to the paper surface and is incident on the color filter 18.

However, light other than yellow is completely absorbed by the color filter 18 regardless of the state of the liquid crystal cell 12. The yellow light is transmitted through the color filter 8 and then enters the liquid crystal cell 12.

When the liquid crystal cell is in the OFF state shown in fig. 10, the direction of the vibration plane of the yellow linearly polarized light is twisted by 90 ° while passing through the liquid crystal cell 12, and the yellow linearly polarized light is incident on the reflective polarizer 16 in a direction perpendicular to the paper surface. Therefore, the direction of the vibration plane of the yellow linearly polarized light is the same as the direction of the easy transmission axis of the reflective polarizer 16, and as a result, the light passes through the reflective polarizer 16, and the ground color (the color of the internal components if the timepiece is mounted) appears dark when viewed from the viewer side.

ON the other hand, when the liquid crystal cell 12 is in the ON state shown in fig. 11, the yellow linearly polarized light is transmitted through the liquid crystal cell 12 without being distorted, and the direction of the vibration plane is incident ON the reflective polarizer 16 while maintaining the original parallel direction. Therefore, the yellow linearly polarized light is specularly reflected by the reflective polarizer 16 because the direction of the vibration plane is perpendicular to the direction of the easy transmission axis of the reflective polarizer 16. Since the reflected light is emitted to the viewing side through a path opposite to the incident time, a yellow metallic tone appears brightly. This is the same effect as placing the yellow filter on top of the mirror.

Therefore, if a voltage is applied between the electrodes of the liquid crystal cell 12 only to a portion where characters of time information or calendar information are displayed, the characters are brightly displayed with a yellow metallic tone (nearly gold color) in a dark background that can be internally transmitted.

As described above, in the timepiece of the present invention, in the area where the time information or the calendar information is digitally displayed, almost all of the colored light incident on the liquid crystal display panel 10 is reflected, so that the colored metallic tone can be brightly displayed.

On the other hand, in the background of the region where the digital display is performed, the light incident on the liquid crystal display panel 10 passes through the reflective polarizer 16, and as a result, the light passes through the side opposite to the viewing side of the reflective polarizer 16. Therefore, the digital display will become a display that stands out in a colorized metallic tone as a whole.

Further, if the easy transmission axis of the reflective polarizer 16 is arranged to be perpendicular to the long axis direction of the liquid crystal molecules on the side opposite to the viewing side of the liquid crystal layer 3, the easy transmission axis of the absorptive polarizer 14 is parallel to the easy transmission axis of the reflective polarizer 16, and therefore the display state in the above example is reversed, and characters and the like can be displayed in a state of being able to transmit through the inside in a background of yellow metal tone.

When filters of different transmission colors are used as the color filter 18, a display color of a metal tint or a background color of an arbitrary color can be obtained.

Therefore, according to the present invention, it is possible to provide a timepiece which is highly changeable in appearance and interesting in comparison with the conventional timepiece in which time information or calendar information is digitally displayed by a method of displaying black on a white background.

Further, such a liquid crystal display panel may be a dot-matrix display liquid crystal display panel, or a simulation display type timepiece in which a plurality of hand patterns are formed so as to be slightly shifted from each other and the hand patterns of the hour hand, minute hand, second hand, and the like can be simulatively displayed.

It is needless to say that the calendar information may be displayed only digitally, the time information may be displayed by a pointer in an analog manner, or only the time information may be displayed, and various functions for other alarms, stopwatches, and the like may be displayed.

As shown in fig. 4, 5, and 7 to 9, even in the liquid crystal display panel in which the color filters 18 are respectively located at different positions, the positions at which the color filters 18 colorize only the light incident on the liquid crystal display panel are different, and the above-described color display function is the same.

Although the above description has been made of the case where the liquid crystal layer 3 enclosed in the liquid crystal cell 12 is a Twisted Nematic (TN) liquid crystal having a twist angle of 90 °, a TN liquid crystal having a twist angle of less than 90 °, a Super Twisted Nematic (STN) liquid crystal having a twist angle of 180 degrees to 270 degrees, a guest host liquid crystal, or the like may be used.

If a super twisted nematic liquid crystal is used, the steepness of the liquid crystal layer can be improved and the contrast can be increased.

When the liquid crystal cell has a function of phase-modulating the linearly polarized light transmitted through the liquid crystal layer 3 to twist the direction of the vibration plane, the easy transmission axes of the absorption polarizer 14 and the reflection polarizer 16 disposed on both sides of the liquid crystal cell 12 are disposed parallel to each other or intersect at the same angle as the twist angle (the easy transmission axes are perpendicular when the twist angle is 90 degrees).

The guest-host liquid crystal is a mixed liquid crystal in which a 2-color dye is dissolved as a solute in a liquid crystal as a solvent. When the alignment state of the liquid crystal molecules is changed by an electric field, the alignment of the 2-color dye can be controlled according to the movement of the liquid crystal molecules, and modulated display can be performed on the absorption of light incident from a certain direction.

When the guest-host liquid crystal is sealed in the liquid crystal cell 12 of the liquid crystal display panel 10, the background portion can be colored in a display state where the time information such as time minutes and seconds of a digital display timepiece or calendar information with date, week, month and the like is displayed, or the area where the hands are artificially displayed is colored in a colored metallic color.

Here, by selecting the specific wavelength transmitted by the color filter 18 and the absorption wavelength of the 2-color dye dissolved in the guest-host liquid crystal, the combination of colors between the region for displaying characters and the like and the background region thereof can be freely configured.

In the above description, the color filter 18 is described as a transmissive color filter, but a dielectric multilayer film may be used.

The dielectric multilayer film is a multilayer film in which dielectrics having different refractive indexes are laminated, and reflects light of a specific wavelength and transmits light of other wavelengths in incident light.

Therefore, when the color filter 18 made of the dielectric multilayer film is disposed on the viewing side of the absorption polarizer 14, only light of a specific wavelength among light incident on the liquid crystal display panel is reflected by the color filter 18 of the dielectric multilayer film, and light other than the specific wavelength is incident on the absorption polarizer 14. Linearly polarized light parallel to the easy transmission axis of the absorption polarizer 14 enters the liquid crystal cell 12. In the background portion of the display, linearly polarized light of light other than the specific wavelength is subjected to 90-degree phase modulation in the liquid crystal cell 12, and is also transmitted through the reflective polarizer 16. On the other hand, in a display portion of characters or the like, since a voltage is applied between electrodes of the liquid crystal cell 12, linearly polarized light of light other than light of a specific wavelength is transmitted through the liquid crystal cell 12 without phase modulation, and is specularly reflected by the reflective polarizer 16 to return to the viewing side.

Therefore, almost all of the incident light is reflected in the area where the time information, the calendar information, or the like is displayed, and the light becomes bright metallic tone. On the other hand, in the background portion of the display, since only light of a specific wavelength is reflected by the color filter 18 of the dielectric multilayer film, the background can be colored, and a bright metallic tone display is performed therein.

In the case of using the dielectric multilayer film, there is almost no loss of light in its constitution. The specific wavelength to be reflected can be freely set by changing the combination of the refractive indices of the dielectric layers.

Further, a color polarizing plate may be used as the color filter 18, and an embodiment thereof will be described in detail later.

In addition, a reflective color filter which transmits only light of a specific wavelength and reflects light of other wavelengths, a fluorescent color filter which has a function of converting the wavelength of incident light, or the like can be used.

[ example of configuration 2 of liquid Crystal display Panel ]

Next, a 2 nd configuration example of a liquid crystal display panel used for a timepiece of the present invention will be described with reference to fig. 12. Fig. 12 is a schematic cross-sectional view showing the structure of the liquid crystal display panel, and the same portions as those in fig. 3 to 11 are given the same reference numerals and are not described.

In the structure of this liquid crystal display panel, the light absorbing plate 13 is simply disposed on the side opposite to the viewing side of the reflective polarizer 16 (the lower side in the figure) unlike the structure shown in fig. 3. The light absorbing plate 13 may be a black light absorbing film, an absorptive polarizer, an absorptive color filter, or the like. When the absorption-type polarizer is used, the easy transmission axis is arranged to be perpendicular to the easy transmission axis of the reflection-type polarizer 16.

When the light absorbing plate 13 is disposed on the side opposite to the viewing side of the reflective polarizing plate 16, the light transmitted through the reflective polarizing plate 16 can be absorbed by the light absorbing plate 13, and the background portion for displaying time information, calendar information, and the like can be displayed in black or dark, and characters and the like can be clearly displayed in a colored metallic tone.

The contrast of the display will be improved. In the case of the reverse display, the time information or the calendar information may be displayed with good contrast by using black or nearly black characters in a bright metal-colored background.

Other functions and applications of various modifications are the same as those of configuration example 1, and therefore, descriptions thereof are omitted.

[ example 3 of the liquid Crystal display Panel ]

Next, a 3 rd configuration example of a liquid crystal display panel used for a timepiece of the present invention will be described with reference to fig. 13. Fig. 13 is a schematic cross-sectional view showing the structure of the liquid crystal display panel, and the same portions as those in fig. 3 to 11 are given the same reference numerals and are not described.

The liquid crystal display panel is different from the configuration shown in fig. 3 only in that the light diffusion plate 15 is disposed on the viewing side (upper side in the drawing) of the absorption polarizer 14.

The light diffusion plate 15 is formed by coating a mixture of silica particles or acrylic porous glass beads or calcium powder as silicon oxide mixed in a binder on a film-shaped substrate.

When the light diffusion plate 15 is disposed on the viewing side of the absorption polarizer 14, light that is specularly reflected from the reflection polarizer 16 and emitted to the viewing side can be diffusely reflected by the light diffusion plate 15. With this, it is possible to make the color tone of the colored metal such as the display time information and the calendar information soft and easy to view, and to widen the viewing angle.

Although the description has been given of the example in which the light diffusion plate 15 is disposed on the viewing side of the absorption polarizer 14, the light diffusion plate 15 may be disposed between the absorption polarizer 14 and the liquid crystal cell 12, or between the liquid crystal cell 12 and the reflective polarizer 16.

Other functions and applications of various modifications are the same as those of the configuration example 1, and therefore, descriptions thereof are omitted.

[ 4 th configuration example of liquid Crystal display Panel ]

Next, a 4 th configuration example of a liquid crystal display panel used for a timepiece of the present invention will be described with reference to fig. 14. Fig. 14 is a schematic cross-sectional view showing the structure of the liquid crystal display panel, and the same portions as those in fig. 3 to 13 are given the same reference numerals and are not described.

In the structure of this liquid crystal display panel, the difference from the structure shown in fig. 3 is that the light absorbing plate 13 is disposed on the side opposite to the viewing side of the reflective polarizer 16, and the light scattering plate 15 is disposed on the viewing side of the absorptive polarizer 14.

This structure is provided with both the light absorbing plate 13 of the liquid crystal display panel of fig. 12 and the light scattering plate 15 of the liquid crystal display panel of fig. 13, and both the functions and effects can be obtained.

That is, the contrast between the background portion and the character portion of the display time information or the calendar information can be increased, and the color metallic tone displayed can be changed to a soft tone to be easily viewed, and the viewing angle can be widened.

Other functions and applications of various modifications are the same as those of the configuration example 1, and therefore, descriptions thereof are omitted.

[ example 5 of the liquid Crystal display Panel ]

Next, a 5 th configuration example of a liquid crystal display panel used for a timepiece of the present invention will be described with reference to fig. 15. Fig. 15 is a schematic cross-sectional view showing the structure of the liquid crystal display panel, and the same portions as those in fig. 3 to 11 are given the same reference numerals and the description thereof will be omitted.

In the structure of this liquid crystal display panel, the backlight 17 is arranged on the side opposite to the viewing side of the reflective polarizer 16 (the lower side in the figure), which is different from the structure shown in fig. 3.

The backlight 17 uses a light source such as an electroluminescent device, a Light Emitting Diode (LED) array, or a cold cathode tube or a hot cathode tube.

When the backlight 17 is disposed on the side opposite to the viewing side of the reflective polarizer 16, half of the light incident on the reflective polarizer 16 from the backlight 17 is transmitted, becomes linearly polarized light, and enters the liquid crystal cell 12. In the background portion for displaying time information, calendar information, and the like, only light having a specific wavelength is transmitted through the color filter 18 by performing 90-degree phase modulation when the linearly polarized light is transmitted through the liquid crystal cell 12, and the light is colored and then transmitted through the absorption type polarizing plate 14 and is emitted to the viewer side.

In a portion where characters such as time information and calendar information are displayed, since a power source is applied between electrodes of the liquid crystal cell 12, linearly polarized light generated by a backlight incident on the liquid crystal cell 12 is transmitted without being phase-modulated by the liquid crystal layer 3, and the vibration plane thereof is perpendicular to the easy transmission axis of the absorption polarizer 14 and absorbed by the absorption polarizer 14.

Therefore, even in a place where there is no external light or little external light, the time information, calendar information, and the like can be displayed in black or dark in a bright background portion formed by colored transmitted light by emitting light from the backlight 17.

The backlight 17 is illuminated by operating any one of the switches 24 of the timepiece shown in fig. 1 as needed.

When the backlight 17 is not emitting light, the colored metallic tone is maintained when displaying time information, calendar information, or the like.

Other functions and applications of various modifications are the same as those of the configuration example 1, and therefore, descriptions thereof are omitted.

[ 6 th configuration example of liquid Crystal display Panel ]

Next, a 6 th configuration example of a liquid crystal display panel used for a timepiece of the present invention will be described with reference to fig. 16. Fig. 16 is a schematic cross-sectional view showing the structure of the liquid crystal display panel, and the same portions as those in fig. 3 to 15 are given the same reference numerals and the description thereof will be omitted.

The liquid crystal display panel is different from the configuration shown in fig. 15 only in that the semi-transmissive plate 19 is disposed between the reflective polarizer 16 and the backlight 17.

In this example, an absorption-type polarizer is used as the semi-transmissive plate 19, and the angle formed by the easy transmission axis and the easy transmission axis of the reflective polarizer 16 is set to 75 degrees.

When the semi-transmissive plate 19 is disposed between the reflective polarizing plate 16 and the backlight 24, when the backlight 17 is not in operation, half of the light transmitted through the reflective polarizing plate 16 can be absorbed by the semi-transmissive plate 19, and the display of the background portion becomes dark, so that the contrast of the display of time information, calendar information, and the like can be improved.

On the other hand, when the ambient external light is reduced and the backlight 17 emits light, the light transmitted through the semi-transmissive plate 19 brightens the background portion, and the characters such as the display time information and the calendar information are displayed in black and dark.

Therefore, the contrast of the display can be improved even when the backlight 17 emits no light or even when the backlight emits light.

The other functions and the application of various modifications are the same as those in the case of configuration examples 1 and 5, and therefore, the description thereof is omitted.

[ 7 th configuration example of liquid Crystal display Panel ]

Next, a 7 th configuration example of a liquid crystal display panel used for a timepiece of the present invention will be described with reference to fig. 17. Fig. 17 is a schematic cross-sectional view showing the structure of the liquid crystal display panel, and the same portions as those in fig. 3 to 15 are given the same reference numerals and the description thereof is omitted.

In the structure of this liquid crystal display panel, the difference from the structure shown in fig. 15 is that the light diffusion plate 15 is disposed only on the viewing side of the absorption polarizer 14.

When the light scattering plate 15 is disposed on the viewing side of the absorption polarizer 14, the light emitted to the viewing side after being specularly reflected by the absorption polarizer 14 can be diffusely reflected by the light scattering plate 15, so that the colored metallic tone of the characters of the display time information or calendar information can be changed to a soft tone to facilitate viewing, and the viewing angle can be widened.

The other functions and the application of various modifications are the same as those in the case of configuration examples 1 and 5, and therefore, the description thereof is omitted.

[ 8 th configuration example of liquid Crystal display Panel ]

Next, an 8 th configuration example of a liquid crystal display panel used for a timepiece of the present invention will be described with reference to fig. 18. Fig. 18 is a schematic cross-sectional view showing the structure of the liquid crystal display panel, and the same portions as those in fig. 3 to 17 are given the same reference numerals and the description thereof will be omitted.

In the structure of this liquid crystal display panel, the difference from the structure shown in fig. 16 is that the light diffusion plate 15 is disposed only on the viewing side of the absorption polarizer 14.

When the light scattering plate 15 is disposed on the viewing side of the absorption polarizer 14, the light emitted to the viewing side after being specularly reflected by the absorption polarizer 14 can be diffusely reflected by the light scattering plate 15, so that the colored metallic tone of the characters of the display time information or calendar information can be changed to a soft tone to facilitate viewing, and the viewing angle can be widened.

The other functions and the application of various modifications are the same as those in configuration examples 1 and 6, and therefore, the description thereof is omitted.

[ 9 th configuration example of liquid Crystal display Panel ]

Next, a 9 th configuration example of a liquid crystal display panel used for a timepiece of the present invention will be described with reference to fig. 19 and 20. Fig. 19 and 20 are schematic cross-sectional views for explaining the structure of the liquid crystal display panel and the principle of color display, and the same parts as those in fig. 3 to 12 are assigned the same reference numerals and the explanation thereof is omitted. The directions of the stripes in the polarizing plates and the solid lines with arrows in fig. 19 and 20 are the same as those described with reference to fig. 10 and 11.

The structure of the liquid crystal display panel differs from the structure shown in fig. 12 only in that: as the color filter, a color polarizing plate 28 is disposed between the absorption polarizing plate 14 and the liquid crystal cell 12 instead of the transmission type color filter 18.

The color polarizing plate 28 transmits only light of a specific wavelength among linearly polarized light having a vibration plane perpendicular to the easy transmission axis and absorbs light of other wavelengths. And the light transmitting member transmits light of a specific wavelength and other wavelengths to linearly polarized light having a vibration plane parallel to the easy transmission axis.

Here, the color polarizing plate 28 is disposed such that its easy transmission axis is perpendicular to the easy transmission axis of the absorption polarizing plate 14.

In this embodiment, the arrangement is made in the order of the absorption polarizer 14, the color polarizer 28, and the liquid crystal cell 12.

Therefore, since the light transmitted through the absorption polarizer 14 is linearly polarized light having a vibration plane perpendicular to the easy transmission axis of the color polarizer 28, only light having a specific wavelength transmits through the color polarizer 28. The other wavelengths of light that have passed through the transmissive polarizer 14 are absorbed by the color polarizer 28. In the illustrated example, the specific wavelength is the wavelength of yellow light.

Fig. 19 shows a path of light other than yellow in light incident on the liquid crystal display panel from the viewing side, and fig. 20 shows a path of light of yellow. The left half of these figures shows an OFF state in which no voltage is applied between the electrodes of the liquid crystal cell 12, and the right half shows an ON state in which a voltage is applied between the electrodes of the liquid crystal cell 12.

As shown in fig. 19, light other than yellow incident on the liquid crystal display panel from the viewing side is transmitted through the absorption polarizer 14, becomes linearly polarized light having a vibration plane parallel to the easy transmission axis thereof (parallel to the paper surface), and enters the color polarizer 28, but the vibration plane is perpendicular to the easy transmission axis of the color polarizer 28, and is totally absorbed by the color polarizer 28.

Therefore, the display is not affected regardless of the ON/OFF state of the liquid crystal cell 12.

As shown in fig. 20, the yellow light incident on the liquid crystal display panel from the viewing side is transmitted through the absorption polarizer 14 and becomes linearly polarized light having a vibration plane parallel to the easy transmission axis thereof, and the light incident on the color polarizer 28 is the same as the light other than yellow light, but the direction of the vibration plane of the yellow linearly polarized light is perpendicular to the easy transmission axis of the color polarizer 28 and can be transmitted through the color polarizer 28, and thus the yellow linearly polarized light is incident on the liquid crystal cell 12 as it is.

In this way, in the background portion where the liquid crystal cell 12 is in the OFF state, the yellow linearly polarized light incident on the liquid crystal cell 12 undergoes 90-degree phase modulation when passing through the liquid crystal cell 12, and the direction of the vibration plane thereof is changed to a direction parallel to the easy transmission axis of the reflective polarizer 16 (perpendicular to the paper surface), and is absorbed by the light absorbing plate 13 disposed on the rear side thereof after passing through the liquid crystal cell 12. And thus appears black or dark as viewed from the viewing side.

ON the other hand, in a display portion of characters or the like in which the liquid crystal cell 12 is turned ON, yellow linearly polarized light incident ON the liquid crystal cell 12 is transmitted through the liquid crystal cell 12 without phase modulation and is incident ON the reflective polarizer 16. Therefore, since the direction of the vibration plane of the yellow linearly polarized light is perpendicular to the easy transmission axis of the reflective polarizer 16, the yellow linearly polarized light is specularly reflected by the reflective polarizer 16 and is emitted to the viewing side through an opposite path.

Therefore, in the area where characters such as time information and calendar information are displayed, almost all of the yellow light incident on the liquid crystal cell 12 is reflected, and the light is brightly displayed in a colored (yellow) metallic tone in a black or dark background.

Therefore, the timepiece using the liquid crystal display panel is also an interesting timepiece with a varied appearance in comparison with a conventional timepiece in which time information, calendar information, and the like are digitally displayed by displaying black on a white background. If the specific wavelength of the light transmitted through the color polarizing plate 28 is selected, that is, the color of the light is selected, the metallic tone can be displayed in various colors.

[ 10 th configuration example of liquid Crystal display Panel ]

Next, a 10 th configuration example of a liquid crystal display panel used for a timepiece according to the present invention will be described with reference to fig. 21 and 22. Fig. 21 and 22 are schematic cross-sectional views for explaining the structure of the liquid crystal display panel and the principle of color display, and the same parts as those in fig. 3 to 12 are assigned the same reference numerals and the explanation thereof is omitted. The directions of the stripes in the polarizing plates and the solid lines with arrows in fig. 19 and 20 are the same as those described with reference to fig. 10 and 11.

The structure of the liquid crystal display panel is different from the structure shown in fig. 19 and 20 only in that the color polarizer 28 as a color filter is disposed between the liquid crystal cell 12 and the reflective polarizer 16.

The color polarizing plate 28 is also a color polarizing plate that transmits only light of a specific wavelength (yellow in this example) in linearly polarized light having a vibration plane perpendicular to the easy transmission axis, and absorbs the other light.

As shown in fig. 21 and 22, the light other than yellow incident on the liquid crystal display panel from the viewing side is totally transmitted through the absorption polarizer 14, becomes linearly polarized light having a vibration plane parallel to the easy transmission axis thereof (parallel to the paper surface), and is incident on the liquid crystal cell 12. When transmitting through the liquid crystal cell 12, the liquid crystal cell 12 is subjected to 90-degree phase modulation in the left half of the OFF state, and the direction of the vibration plane thereof is changed to linearly polarized light in a direction parallel to the easy transmission axis of the color polarizer 28, and the linearly polarized light is incident on the color polarizer 28.

Therefore, in the background portion where the liquid crystal cell 12 is in the OFF state, light other than yellow light is also transmitted, and as shown in fig. 21 and 22, the light is absorbed by the light-absorbing plate 13 after passing through the color polarizing plate 28 and also passing through the reflective polarizing plate 16 whose easy transmission axis is arranged parallel to the easy transmission axis of the color polarizing plate 28.

In a display region of characters or the like in which the liquid crystal cell 12 is in an ON state, light other than yellow is absorbed by the color polarizing plate 28 as shown in fig. 21. The yellow light is transmitted through the color polarizer 28 and enters the reflective polarizer 16, but the direction of the vibration plane is perpendicular to the easy transmission axis of the reflective polarizer 16, and therefore, the yellow light is specularly reflected by the reflective polarizer 16 and exits to the viewer through the opposite path. For this reason, almost all of the colored light entering the liquid crystal cell 12 is reflected and emitted to the viewer side as a result.

Therefore, even when the liquid crystal display panel is used in a timepiece, time information, calendar information, and the like can be displayed in a dark or dark background with a bright colored metallic tone.

Therefore, the timepiece using the liquid crystal display panel is also an interesting timepiece with a varied appearance in comparison with a conventional timepiece in which time information, calendar information, and the like are digitally displayed by displaying black on a white background.

If the specific wavelength of the light transmitted through the color polarizing plate 28 is selected, that is, the color of the light is selected, the metallic tone can be displayed in various colors.

In the 9 th and 10 th configuration examples, the color polarizer 28 may be provided on the viewing side of the absorption polarizer 14 or on the inner surface side of any one of the substrates in the liquid crystal cell 12, as in the color filter 18 described in the 1 st configuration example.

Various modifications other than color filter 18 described in configuration example 1 can be similarly applied to configuration examples 9 and 10 described above.

Possibility of industrial utilization

As is apparent from the above description, the timepiece of the present invention can display time information and calendar information in bright relief by coloring the metal tone in a dark background and by coloring the colored metal tone in black or dark in contrast, and the display color can be arbitrarily selected.

Therefore, compared with a conventional timepiece in which time information, calendar information, and the like are digitally displayed by displaying black on a white background, it is possible to provide a timepiece which is interesting and has a colorful change in appearance.

Further, the present invention can be applied to a timepiece with a backlight that can be used even in an environment with little or no external light.

The present invention is not limited to a timepiece that digitally displays time information or calendar information, and may be a timepiece of an analog display type in which the liquid crystal display panel is a dot-matrix display, or a plurality of hands are formed so that the hands of an hour hand, a minute hand, a second hand, and the like are displayed in an analog map with a slight angle shift.

It is needless to say that the calendar information may be displayed only digitally and the time information may be displayed by a pointer in an analog manner, or only the time information may be displayed and various functions such as an alarm and a stop watch may be displayed in addition.

Claims (19)

1. A timepiece including a liquid crystal display panel that displays at least either time information or calendar information, the liquid crystal display panel comprising:

a liquid crystal cell in which liquid crystal is sealed between 2 transparent substrates each having electrodes on the inner surfaces thereof facing each other;

an absorption-type polarizing plate disposed on the viewing side of the liquid crystal cell and absorbing linearly polarized light having a vibration plane in a direction perpendicular to the easy transmission axis;

a reflective polarizer disposed on the opposite side of the liquid crystal cell from the viewing side and reflecting linearly polarized light having a vibration plane in a direction perpendicular to the easy transmission axis;

and a color filter disposed on a viewing side of the absorption polarizer or between the absorption polarizer and the reflection polarizer.

2. The timepiece of claim 1, wherein: the light absorbing plate is disposed on a side of the liquid crystal display panel opposite to a viewing side of the reflective polarizing plate.

3. The timepiece of claim 1, wherein: the light scattering plate is disposed on the viewing side of the absorption polarization plate of the liquid crystal display panel.

4. The timepiece of claim 1, wherein: a light scattering plate disposed on a viewing side of the absorption type polarizing plate of the liquid crystal display panel; the light absorbing plate is disposed on a side of the liquid crystal display panel opposite to a viewing side of the reflective polarizing plate.

5. The timepiece of claim 1, wherein: the backlight is disposed on a side of the liquid crystal display panel opposite to a viewing side of the reflective polarizing plate.

6. The timepiece of claim 5, wherein: a semi-transmissive plate is provided between the reflective polarizing plate and the backlight of the liquid crystal display panel.

7. The timepiece of claim 6, wherein: the semi-transmissive plate is an absorption-type polarizing plate.

8. The timepiece of claim 1, wherein: a light scattering plate disposed on a viewing side of the absorption type polarizing plate of the liquid crystal display panel; the backlight is disposed on a side of the liquid crystal display panel opposite to a viewing side of the reflective polarizing plate.

9. The timepiece of claim 8, wherein: a semi-transmissive plate is provided between the reflective polarizing plate and the backlight of the liquid crystal display panel.

10. The timepiece of claim 9, wherein: the semi-transmissive plate is an absorption-type polarizing plate.

11. The timepiece according to any one of claims 1 to 10, characterized in that:

the easy transmission axis of the absorption type polarization plate arranged at the viewing side of the liquid crystal unit is parallel to the long axis direction of the viewing side liquid crystal molecules in the liquid crystal layer of the liquid crystal unit,

the easy transmission axis of the reflective polarizing plate is parallel or perpendicular to the long axis direction of the liquid crystal molecules on the side opposite to the viewing side in the liquid crystal layer of the liquid crystal cell.

12. The timepiece according to any one of claims 1 to 10, characterized in that:

the easy transmission axis of the absorption type polarization plate arranged at the viewing side of the liquid crystal unit is vertical to the long axis direction of the viewing side liquid crystal molecules in the liquid crystal layer of the liquid crystal unit,

the easy transmission axis of the reflective polarizing plate is parallel or perpendicular to the long axis direction of the liquid crystal molecules on the side opposite to the viewing side in the liquid crystal layer of the liquid crystal cell.

13. The timepiece according to any one of claims 1 to 12, wherein: the color filter of the liquid crystal display panel is a selective transmission type color filter which substantially transmits only light of a specific wavelength.

14. The timepiece according to any one of claims 1 to 12, wherein: the color filter of the liquid crystal cell is a color polarizing plate: linearly polarized light having a plane of vibration perpendicular to the easy transmission axis absorbs light of other wavelengths only light of a specific wavelength, while linearly polarized light having a plane of vibration parallel to the easy transmission axis transmits all light.

15. The timepiece according to any one of claims 1 to 12, wherein: the color filter of the liquid crystal display panel is a dielectric multilayer film that reflects light of a specific wavelength among incident lights and transmits light of other wavelengths.

16. The timepiece according to any one of claims 1 to 15, wherein: the liquid crystal layer of the liquid crystal cell is formed of any one of twisted nematic liquid crystal, super twisted nematic liquid crystal, or guest-host liquid crystal.

17. The timepiece according to any one of claims 1 to 16, wherein: the color filter of the liquid crystal display panel is disposed between the absorption polarizer and the liquid crystal cell.

18. The timepiece according to any one of claims 1 to 16, wherein: the color filter of the liquid crystal display panel is disposed between the liquid crystal cell and the reflective polarizer.

19. The timepiece according to any one of claims 1 to 16, wherein: the color filter of the liquid crystal display panel is provided between the transparent substrate and the liquid crystal layer constituting the liquid crystal cell.