JP2000137444A - Light emitting display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to visually recognize a display without lighting a backlight even in a dimly-lit place. SOLUTION: This light emitting display device is provided with a semi-transparent reflective plate 23 which transmits a part of light transmitted through a liquid crystal display panel 16 transmitting ultraviolet rays and reflects the other part of the light, and a fluorescent layer 24 which emits light reacting with ultraviolet rays contained in the light transmitted through the plate 23. Therefore, since, in a bright place, most of the light except a part of external light transmitted through the liquid crystal panel 16 is reflected by the plate 23 and made to exit to the side of an observer, information on the liquid crystal panel 16 can visually be recognized, while, in a darkish place, little light is transmitted through the liquid crystal display panel 16 and reflected by the plate 23, but the light is partly transmitted through the plate 23 and made incident on the fluorescent layer 24, and the fluorescent layer 24 reacts with the ultraviolet rays contained in this partial incident light and emits light, therefore, this makes it possible to illuminate the backside of the liquid crystal display panel 16, and visually recognize the information on the liquid crystal display panel 16 even in the darkish place.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a light-emitting display device used for electronic devices such as watches and telephones.

[0002]

2. Description of the Related Art Conventionally, in a wristwatch, a liquid crystal display panel for displaying information such as time is provided in a wristwatch case.
A backlight device is provided on the back side of the liquid crystal display panel, and by illuminating the backlight device to illuminate the back side of the liquid crystal display panel, it is possible to display on the liquid crystal display panel not only in a dark place but also in a dark place. In some cases, the displayed information can be visually recognized.

[0003]

However, in such a wristwatch, the information displayed on the liquid crystal display panel cannot be visually recognized unless the backlight device is turned on not only in a dark place but also in a dim place. There was an inconvenience.

An object of the present invention is to make it possible to visually recognize a display without turning on a backlight in a dark place.

[0005]

The present invention has the following arrangement to solve the above-mentioned problems. In addition,
Each component is denoted by a reference number of a drawing attached to each element described in the section of each embodiment described later together with parentheses. According to the first aspect of the present invention, as shown in FIGS. 1 to 5, a liquid crystal display panel (16) that transmits ultraviolet light, and a part of light transmitted through the liquid crystal display panel is transmitted. Transflective reflector (23) that reflects other light
And a fluorescent layer (24) that emits light in response to ultraviolet light contained in the partial light transmitted through the transflective plate. According to this invention, in a bright place, among the external light transmitted through the liquid crystal display panel, most of the light excluding a part of the light is reflected by the semi-transmissive reflector and emitted to the observer side, The information displayed on the liquid crystal display panel can be viewed well, and in a dimly lit place, little external light passes through the liquid crystal display panel and little light is reflected by the semi-transmissive reflector. Is transmitted through the semi-transmissive reflection plate and enters the fluorescent layer, and the fluorescent layer reacts to ultraviolet light contained in a part of the incident light to emit light. Can be illuminated, so that the information displayed on the liquid crystal display panel can be visually recognized even in a dim place without using a backlight.

Further, according to a third aspect of the present invention, as shown in FIGS. 6 and 7, a display mark (27
a) a translucent display panel (switch display panel 27) on which a display is printed and a fluorescent layer (4) that emits light in response to ultraviolet light contained in light transmitted through the display panel;
1). According to the invention,
In bright places, external light is absorbed by the printed portion of the display mark on the display panel, and external light is transmitted through the other portions to enter the phosphor layer, and the phosphor layer emits light by the ultraviolet light included in the incident light. In addition, most of the other light is reflected and these lights are emitted to the observer side, so that the display mark can be visually recognized well. The light absorbed by the printed portion of the display mark and the light transmitted through other portions and incident on the fluorescent layer are small, but the fluorescent layer reacts to the ultraviolet light contained in the light incident on the fluorescent layer. Since it emits light, it is possible to illuminate the back side of the display panel by the emission of the fluorescent layer, thereby using a backlight without using a backlight even in a dim place.
The display mark on the display panel can be visually recognized.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [First Embodiment] A first embodiment in which a light-emitting display device of the present invention is applied to a wristwatch will be described below with reference to FIGS. FIG. 1 is a front view of a wristwatch, and FIG. 2 is a sectional view taken along line AA of FIG. This watch is
A watch case 1 is provided. This watch case 1
As shown in FIG. 1, the whole is formed in a substantially rectangular shape, and almost half of the 6 o'clock side is inclined obliquely downward (downward left in FIG. 2) as shown in FIG. A plurality of pushbutton switches 2 for mode switching, time adjustment, and the like are provided on the outer peripheral surface of the wristwatch case 1 on the 12 o'clock side. A watch band 3 is attached. As shown in FIG. 2, a watch glass 4 is mounted on the upper part on the 12 side of the watch case 1, and a watch module 5 is stored in the watch case 1 corresponding to the watch glass 4. . A key input section 6 is provided on the upper surface of the wristwatch case 1 on the 6 o'clock side.
Is provided. A back cover 7 is attached to the lower surface of the watch case 1 with screws 9 via a waterproof packing 8 from the end at 12 o'clock to the end at 6 o'clock.

[0008] The watch module 5 in the watch case 1
As shown in FIGS. 2 to 4, an upper housing 10 and a lower housing 11 are provided, a circuit board 12 is disposed therebetween, a ground plate 13 is disposed on a lower surface of the lower housing 11, and an outer peripheral portion of the ground plate 13 is provided. The hook portion 13a extending upward from the upper housing 10 is locked by a locking projection 10a provided on the outer peripheral surface of the upper housing 10 as shown in FIG. It has a mounted configuration. In this case, the circuit board 12 is provided with an electronic component 14 such as an LSI. A battery 15 is housed in the lower housing 11. On the other hand, as shown in FIG. 4, a liquid crystal display panel 16 is held in an upper part in the upper housing 10 in a state of being electrically connected to the circuit board 12 by an interconnector 17. This liquid crystal display panel 16
Liquid crystal (not shown) between a pair of upper and lower glass substrates 18 and 19
, An upper polarizing plate 21 provided on the upper surface of the liquid crystal cell 20, and a lower polarizing plate 22 provided on the lower surface of the liquid crystal cell 20. Liquid crystal cell 20
Is configured such that transparent electrodes (not shown) are formed on opposing surfaces of a pair of glass substrates 18 and 19, respectively, and an electric field is applied between the transparent electrodes to control the light transmission state of the liquid crystal layer. ing. Further, the upper polarizing plate 21 and the lower polarizing plate 22 are arranged with their transmission axes facing each other at a predetermined angle so as to transmit light when the electric field is not applied to the liquid crystal cell 20 and block light when the electric field is applied. In addition, it is configured to transmit not only visible light but also ultraviolet light having a wavelength of 340 to 400 nm. The liquid crystal display panel 16 is of a positive type that blocks light when an electric field is applied and transmits light when a non-electric field is applied.

A transflective plate 23, a fluorescent layer 24, and an EL (electroluminescence) element 25, which is a backlight element, are arranged below the liquid crystal display panel 16 in the upper housing 10 from the top. They are arranged in a stacked state. The transflective plate 23 is configured to transmit a part of the light transmitted through the liquid crystal display panel 16 and reflect the other light.
The fluorescent layer 24 emits light by ultraviolet light included in the light transmitted through the transflective plate 23, and is printed on the lower surface of the transflective plate 23. That is, the fluorescent layer 24 is composed of a crystal matrix such as a metal oxide or a sulfide, and an activator or a co-activator such as a rare earth or a metal.
When ultraviolet light of 00 nm is irradiated, light is absorbed and reflected at the same time by the crystal base, and activator and light are also absorbed by the co-activator, becoming a kind of dispersion medium, stimulating the crystal base,
It is configured to emit fluorescence when excited without generating heat. The matrix of the crystal such as a metal oxide or a sulfide is Y ₂ O ₂ S, BaMgAl ₁₄ or the like, and the activator such as a rare earth or a metal is Eu, Mn or the like. The emission colors of the fluorescent layer 24 are basically three colors of red, green and blue.
By combining the colors, eight colors of white, yellow, orange, pink and violet are obtained. EL
The element 25 is an electroluminescent element in which an organic or inorganic EL layer which emits light by application of an electric field is provided between electrodes.
The emitted light is transmitted through the fluorescent layer 24 and the transflective plate 23 to illuminate the lower surface side of the liquid crystal display panel 16.

The key input section 6 provided on the upper surface of the wristwatch case 1 on the 6 o'clock side is provided with a decorative plate 26 and a switch display panel 27 in order from the top as shown in FIGS. 1, 2 and 5. , And the planar switch 28 are arranged in a stacked state. The decorative plate 26 is made of a metal plate, and has openings 26a arranged vertically and horizontally. The switch display panel 27 is made of a transparent or translucent flexible sheet having a light-transmitting property, and is arranged on the lower surface of the decorative plate 26. On the upper surface of the switch display panel 27, a key top 27a is formed so as to protrude upward through each opening 26a of the decorative board 26, and on the lower surface thereof,
The display mark 27b such as a number or a symbol is a key top 27a.
Is printed in correspondence with. In addition, this display mark 27
A flat switch 28 is adhered via a double-sided adhesive tape 29 to the lower surface of the switch display panel 27 on which b is printed. The flat switch 28 has a configuration in which the conductive sheet 30 and the contact sheet 31 are arranged so as to be separated from each other via a spacer 32 so as to be able to contact and separate. In this case, a pair of comb-shaped contacts 31 a are formed on the contact sheet 31 corresponding to the key tops 27 a of the switch display panel 27, and one end of the contact sheet 31 extends to the watch module 5. And is electrically connected to the circuit board 12. In the flat switch 28, when the key top 27a of the switch display panel 27 is pressed, the conductive sheet 30 at a position corresponding to the pressed key top 27a is connected to the pair of contacts 31a of the contact sheet 31 at the corresponding position. Contact, thereby outputting a switch signal.

In such a wristwatch, information such as the time is usually displayed on the liquid crystal display panel 16, and the displayed information can be viewed. That is, in a bright place, most of the external light transmitted through the liquid crystal display panel 16 except for a part of the light is reflected by the semi-transmissive reflection plate 23 and emitted to the observer side. The information displayed on the panel 16 can be viewed well. In a dimly lit place, the amount of external light transmitted through the liquid crystal display panel 16 is small and the amount of light reflected by the transflective plate 23 is small. 24, the fluorescent layer 24 emits light in response to ultraviolet light contained in a part of the incident light, so that the lower surface side of the liquid crystal display panel 16 can be illuminated by the emission of the fluorescent layer 24. This allows the EL element 25 to be used in a dark place.
The information displayed on the liquid crystal display panel 16 can be visually recognized without turning on. In a dark place where no ultraviolet light can be obtained, the EL element 25 is turned on,
The light from the EL element 25 is transmitted to the fluorescent layer 24 and the
Illuminates the lower surface side of the liquid crystal display panel 16 by transmitting light, so that the liquid crystal display panel
Can be visually recognized.

[Second Embodiment] Next, a second embodiment in which the light emitting display device of the present invention is applied to a wristwatch will be described with reference to FIGS. The same parts as those in the first embodiment shown in FIGS. 1 to 5 are denoted by the same reference numerals, and description thereof will be omitted. This wristwatch has the same configuration as the first embodiment except that a fluorescent layer 41 is provided in the key input unit 40. That is, the key input unit 40 includes, in order from the top, the decorative board 26, the switch display panel 27, and the fluorescent layer 4
1 and the planar switch 28 are stacked. The fluorescent layer 41 emits light by ultraviolet light included in light transmitted through the switch display panel 27,
It is printed on the lower surface of the switch display panel 27 so as to cover the display mark 27b. Like the fluorescent layer 24 of the first embodiment, the fluorescent layer 41 includes a crystal matrix such as a metal oxide or a sulfide, and an activator or a co-activator such as a rare earth or a metal. When irradiated, light is absorbed and reflected at the same time by the crystal matrix, and is also absorbed by the activator and co-activator, forming a kind of dispersion medium that stimulates the crystal matrix and is excited without heat to generate fluorescence. Is configured to emit. The flat switch 28 is adhered to the lower surface of the fluorescent layer 41 via a double-sided adhesive tape 29.

In the key input section 40 of such a wristwatch,
When the key top 27a of the switch display panel 27 is pressed, the switch display panel 27 at the location of the key top 27a bends, and the conductive sheet 30 corresponding to the bent location.
Correspond to a pair of contacts 3 of the contact sheet 31 at a corresponding position.
The switch signal is output by touching the switch 1a, whereby an input operation is performed. When such an input operation is performed in a bright place, external light is absorbed by the display mark 27b of the switch display panel 27, passes through the other portions, enters the fluorescent layer 41, and is included in the incident light. The fluorescent layer 41 emits light by the ultraviolet rays, and most of the other incident light is reflected, and these lights are emitted to the observer side.
The display mark 27b can be visually recognized well. In a dark place, the amount of external light is small, and the amount of light absorbed by the display mark 27b of the switch display panel 27 and the amount of light transmitted through other portions and entering the fluorescent layer 41 are small. Since the fluorescent layer 41 emits light in response to the ultraviolet light included in the light thus emitted, the lower surface side of the switch display panel 27 can be illuminated by the light emission of the fluorescent layer 41. The 27 display marks 27b can be visually recognized.

In the first and second embodiments, the case where the liquid crystal display panel 16 is of the positive type, which blocks light when an electric field is applied and transmits light when a non-electric field is applied, is not limited to this. For example, the present invention can be applied to a negative-type liquid crystal display panel that blocks light when no electric field is applied and transmits light when an electric field is applied. In the first and second embodiments, the case where the display mark 27b such as a number or a symbol is printed on the lower surface of the switch display panel 27 has been described. However, the present invention is not limited to this. A configuration may be adopted in which display marks 27b such as numbers and symbols are displayed in a transparent white state by printing on portions other than the portions. In addition, the first and second
In the embodiment, the case where the present invention is applied to a liquid crystal display unit or a key input unit of a wristwatch is described. However, the present invention is not limited to this. It can be widely applied to key input units and the like.

[0015]

As described above, according to the first aspect of the present invention, a part of the light transmitted through the liquid crystal display panel that transmits ultraviolet light is transmitted and the other light is reflected. And a fluorescent layer that emits light in response to ultraviolet light contained in a part of the light transmitted through the semi-transmissive reflective plate, so that the light transmitted through the liquid crystal display panel in a bright place. Of the external light, most of the light excluding a part of the light is reflected by the semi-transmissive reflection plate and emitted to the observer side, so that the information displayed on the liquid crystal display panel can be visually recognized well. In a dimly lit place, less external light passes through the liquid crystal display panel and less light is reflected by the transflector, but some of the light passes through the transflector and enters the fluorescent layer. And the ultraviolet light contained in some of the incident light When the fluorescent layer reacts to emit light, the light emitted from the fluorescent layer can illuminate the back side of the liquid crystal display panel, thereby displaying the image on the liquid crystal display panel without using a backlight even in a dim place. Information can be viewed.

According to the third aspect of the present invention, there is provided a translucent display panel on which display marks such as characters and symbols are displayed and printed, and an ultraviolet ray included in light transmitted through the display panel. Since it has a fluorescent layer that emits light in response, in a bright place, external light is absorbed by the printed portion of the display mark of the display panel, and the external light is transmitted through the other portion and enters the fluorescent layer, The fluorescent layer emits light due to the ultraviolet light contained in the incident light, and most of the other light is reflected, and the light is emitted toward the observer, so that the display mark can be visually recognized well. In a dimly lit place, there is little external light, and little light is absorbed by the printed part of the display mark of the display panel and light that passes through other parts and enters the fluorescent layer is small. Contained in the light By fluorescent layer emits light in response to external, this by emission of the fluorescent layer can illuminate the back surface of the display panel, it is possible to view the display mark of the display panel thereby also dim place.

[Brief description of the drawings]

FIG. 1 is an enlarged front view showing a first embodiment in which a light-emitting display device according to the present invention is applied to a wristwatch;

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is an enlarged front view of the timepiece module of FIG. 2;

FIG. 4 is a sectional view taken along line BB of FIG. 3;

FIG. 5 is an enlarged sectional view of a main part of FIG. 2;

FIG. 6 is an enlarged sectional view showing a second embodiment in which the light emitting display device of the present invention is applied to a wristwatch.

FIG. 7 is an enlarged sectional view of a main part of FIG. 6;

[Explanation of symbols]

 Reference Signs List 16 liquid crystal display panel 23 transflector 24, 41 fluorescent layer 25 EL element 27 switch display panel 27a key top 27b display mark 28 flat switch

Continued on the front page F-term (reference) 2F002 AA06 AB02 AB03 AB04 BA02 BA26 EA01 EA04 EB03 EF01 EF02 2H088 EA27 HA21 HA28 MA01 5G435 AA01 AA03 BB12 BB15 BB16 CC12 DD09 EE03 EE04 EE36 FF03 GG25 HH02H05

Claims (4)

[Claims] 1. A liquid crystal display panel that transmits ultraviolet light, a transflective plate that transmits a part of the light transmitted through the liquid crystal display panel and reflects other light, A light emitting display device comprising: a fluorescent layer that emits light in response to ultraviolet light contained in the partial light transmitted through the reflecting plate. 2. A backlight element for illuminating the rear surface of the display panel through the fluorescent layer and the transflective plate on the back side of the fluorescent layer. 2. The light-emitting display device according to 1. 3. A light-transmitting display panel on which display marks such as characters and symbols are displayed and printed, and a fluorescent layer which emits light in response to ultraviolet light contained in light transmitted through the display panel. A light-emitting display device, characterized in that: 4. The display panel has a plurality of key tops, and a flat switch in which a plurality of switch contacts are arranged corresponding to the plurality of key tops is provided on a back side of the fluorescent layer. The light-emitting display device according to claim 3, wherein: