JPS5836757B2 - densid cay - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a display system for an electronic timepiece that displays information using a display element having an electro-optical effect such as liquid crystal or electrochromism.

FIG. 1 shows an embodiment of the configuration of the present invention.

1112 is a transparent glass plate on which electrodes are deposited, 13 is a spacer, and 14 is a liquid crystal.

The liquid crystal has a structure in which it is sandwiched between transparent glass plates via electrodes.

15 is one electrode that applies a voltage to the liquid crystal, and 16 is the other electrode corresponding to 15 that also applies a voltage.

The block displayed by electrodes 15 and 16 is 1-a.
This is the part.

Reference numeral 17 denotes an electrode that is deposited on the transparent glass plate 12 and is made at a different location from the electrode 15. Reference numeral 18 denotes an electrode that is deposited on the transparent glass plate 11 corresponding to 17.

The block displayed by electrodes 17 and 18 is part 1-b.

In the display panel having the above structure, a display portion corresponding to each independent electrode of the group of electrodes 16 in block 1-a is defined as one display element.

First, the block 1-a in FIG. 1 will be explained.

There are display elements with the number of independent electrodes shown as 16, and the electrodes 15 on one side of the group of display elements are all connected in common.

At this time, a certain type of information corresponding to the number of display elements is displayed in the block 1-a.

In the block 1-b, the display elements are connected in a different way from the block 1-a, and the electrodes 17 are one electrode for each group of display elements, so that the number of electrodes 17 varies depending on the number of groups. It has a number of electrodes.

Further, the electrode 1B is an electrode connected to each display element of another group for one display element of a certain group.
It has a number of electrodes equal to the maximum number of display elements included in one group.

For each block constructed using different electrode connection methods as described above, display driving conditions suitable for each block are selected, and each block is displayed under different driving conditions.

The display method that is generally used in current liquid crystal display watches by connecting electrodes is a so-called static display.

In the static display method, the plane electrode covering one group of display elements is a common electrode for all groups, but the other electrode of each display element is an independent segment electrode, which increases the amount of information displayed. This inevitably increases the number of electrodes, which is unfavorable in terms of implementation.

Furthermore, since the number of drive circuits increases, the chip area of the IC also increases, leading to an increase in cost.

However, in the static display method, each display element is displayed in a waveform with a duty of nearly 100, so the display contrast is generally good.

In the static display method, display information is calculated using static drive or dynamic drive.

On the other hand, a matrix display method using electrode connections is a preferable display method in terms of implementation because it requires fewer electrodes than a static display by configuring each display element in a matrix.

In particular, as watches become more multi-functional, it is preferable that the amount of information displayed increases.

However, when a matrix display is performed using a material such as a liquid crystal, a crosstalk phenomenon occurs, and since each display element is displayed using a drive waveform with a duty smaller than 100 degrees, it is inevitable that The display contrast decreases.

As described above, both the static display method and the matrix display method have advantages and disadvantages, so depending on the information to be displayed, the optimal display system for a watch can be obtained by using either of the two display methods.

When there is a lot of information to be displayed, the present invention allows some information to be displayed statically and some information to be displayed in a matrix.
The purpose is to reduce the number of electrodes, drive circuits, and other clock hardware by the amount of matrix display.

FIG. 2 shows an example of a clock display panel.

21 represents the entire display panel, 22 is a display element group that displays hours and minutes, and 23 is a display element group that displays information other than hours and minutes.

Hour and minute information such as 22 is the most important information for a watch's functions, and it is necessary to maintain clear display contrast at all times.

Group 23 is a group that displays optional information on the watch, such as seconds, day of the week, internal status of the watch, and chronograph.The number of display elements increases as watches become more multifunctional. In order to reduce the number of wires in the drive circuit, it is convenient to configure the display elements in a matrix.

That is, the 22nd group performs static display with good display contrast, and the 23rd group performs matrix display.

In FIG. 2, for example, one segment, ie, 221, making up the 220-character type f'', and one part, ie, 231, making up 23 are one display element.

The correspondence between FIG. 1 and FIG. 2 will be explained.

The block in FIG. 1-a is statically arranged, so to speak, and displays minute information at 22 in FIG.

Blocks i-b in FIG. 1 are constructed in a matrix, so to speak, and display information other than the hours and minutes at 23 in FIG.

As described above, in one clock display panel, two blocks with different electrode connection methods are created, and which block is used to display information is determined depending on the type of information to be displayed.

If the electrodes are connected in different ways, the two blocks cannot be driven under the same driving conditions.

Therefore, an optimal drive waveform is created for each block and displayed under optimal conditions.

FIG. 3 shows a block diagram of the present invention.

31 is an oscillator such as a crystal oscillator, 32 is a frequency divider, 33 is a logic mechanism 1, 34 is a logic mechanism 2, 35 is a clock display panel, and 36 is a display element block 1 that displays information calculated by the logic mechanism 1. , 37 are display element blocks 2 that display information calculated by the logic mechanism 2.

The electrodes of the display element blocks 1 and 2 are connected in different ways, and the logic mechanisms are different depending on the display blocks.

In relation to FIG. 2, display element block 1 36 displays 220 hour and minute information, and display element block 2 37 displays information other than hours and minutes.

Although it is preferable in terms of implementation to display all the display elements included in the display panel in a matrix, as the amount of information to be displayed increases, it becomes difficult in terms of display contrast. When desired, a static display is used, and when optional information is displayed, a matrix display is used to provide each display with optimal driving conditions to create an optimal display system.

FIGS. 4a and 4b show configuration diagrams of each group of display elements in FIG. 2.

FIG. 4a shows the display groups of FIG. 23 arranged in a matrix.

D1 and D2 are lines that serve as common electrodes for each display group, and a-
g is a line serving as a segment electrode.

For example, the display element group D0 is a 10 second unit signal? information and AM/PM information can be displayed, and the display element group D2 can be made to display day of the week information.

For example, D1・a is O~9 seconds, D・d is 30~39 seconds, D
1.g is AM/PM information, D2.a is Sunday, D2.d
displays information such as Wednesday.

Note that although dotted segments are illustrated here, each segment may be used alone or a plurality of segments may be combined to represent characters and figures.

FIG. 4b shows a static configuration of display elements for displaying minute information in the case of FIG. 22.

It consists of a common electrode that covers the entire display element and a segment electrode line for each display element as shown.

In FIG. 3, the logic mechanism 33 creates a drive waveform for static display.

FIG. 5 shows an example of a typical waveform created by the logic mechanism 1.

FIG. 5a shows an input signal, and b shows a signal constantly applied to the common electrode, for example, a signal of 32 Hz.

C is a signal obtained by converting the signal of a into a state to be displayed.

d is the signal actually applied to the liquid crystal. In this way, in static display, the duty is close to 100%, and the contrast is good.

However, as the amount of information to be displayed increases, the hardware scale of the logic mechanism 1 and the hardware scale of the display elements increase.

The logic mechanism 34 creates a drive waveform for matrix display.

FIG. 6 shows an example of a typical waveform created by the logic mechanism 34.

In FIG. 6, a, b, and c are signals applied to each digit.

d is a signal applied to a certain segment.

e, f, g are inter-electrode voltage waveform diagrams of the liquid crystal.

In e, f, and g, e is in the display state, and f and g are in the non-display state.

In this way, in matrix display, different from static display, it is necessary to prepare various voltage levels in order to prevent crosstalk.

Therefore, the driving voltage level of the logic mechanism 33 and the driving voltage level of the logic mechanism 34 must be different.

FIG. 7 shows a block diagram when a display group for matrix display is provided with another voltage conversion mechanism for display.

Reference numeral 71 denotes a clock power source for driving the oscillator 31 and branch unit 32.

The voltage level of the logic mechanism 33 is converted by the boost mechanism 72, and the display block 36 is statically displayed.

The voltage level of the logic mechanism 34 is converted by the voltage conversion mechanism 2 73, and a matrix display 37 is performed.

In this way, the display becomes clear by providing another voltage conversion mechanism for the matrix display group whose display becomes unclear depending on the driving conditions.

The voltage converting mechanism at this time can perform not only voltage boosting but also voltage dropping in accordance with the threshold voltage of the display element.

As a function of the clock, it is not necessary to display information all the time, and it may be necessary to display it only when you want to know it.

Generally, the matrix display method consumes more power than the static display method, so if only the display elements are prepared and the display is performed only when desired, the power consumption will not increase significantly.

That is, it is sufficient to operate the voltage conversion mechanism shown in FIG. 7 intermittently only at arbitrary times.

FIG. 8 shows a block diagram for intermittently operating the voltage conversion mechanism.

Reference numeral 81 denotes an arbitrary operating mechanism, and when the operating mechanism is in an OFF state, the display element block 37 is only subjected to logic calculations and is not displayed.

On the other hand, the group in display 36 is displayed.

When the operating mechanism is turned on, the voltage converting mechanism 73 operates, and the blocks on the display 37 are displayed.

In this way, an increase in power consumption O in matrix display is prevented.

It is effective to vary the driving and display force formulas depending on the frequency of the information to be displayed next.

Since seconds information and hour information differ greatly in information frequency1)3, hour information with a low frequency is displayed in a different display method than minutes and seconds, that is, static display, and second and minute information are displayed in matrix. It is also effective to configure each group in the form of a matrix display.

As watches become more multi-functional and the amount of information displayed increases, it becomes necessary to select information suitable for matrix display and static display. Optimal clock system.

FIG. 9 shows a drive waveform diagram of the display group of FIG. 4a.

Since this is an example in which AM/PM information is not displayed, D
1.g is not always displayed.

The case where the D1 digit is selected and seconds information is displayed will now be described.

Figure 9a shows the D1 signal created by the branching unit.

b is a signal obtained by boosting the D1 signal to four times the voltage level and shifting the level.

That is, it is a drive signal for the selected display digit.

At this time, no signal is applied to the D2 digit, which is at ground level.

C, d are lO second signals produced by the seconds counter.

For example, C is a signal representing 0 to 9 seconds, and d is a signal representing 10 to 19 seconds.

A total of six types of such signals are generated by ring counters, etc., but the second signal will be omitted from the explanation below.

e is a signal obtained by calculating the C signal and the a signal, boosting the voltage twice and level-shifting the signal, and f is a signal obtained by calculating the level-shifting signal d and the a signal.

A signal that has been subjected to such calculation and level shift is a segment drive signal.

When the signals c and d are at the L level, they are converted into signals synchronized with the signal a, and when the signals c and d are at the H level, they are converted into signals whose phases are inverted.

When the above signals are applied to the display element, the liquid crystal displays g,
A voltage as shown in h appears.

In g and h, the voltage at the level is hidden,
A voltage of ±3■o level is the display level.

At this time, the liquid crystal threshold voltage VTR is ■.

If the value is smaller than , crosstalk will not occur and will not be displayed in the non-selected state, and will be displayed as 3■o.

At this time, no signal is applied to the common electrode of the unselected D2 digit, but since the segment signal is AC,
Since no DC component is added and the lifespan of the liquid crystal is not shortened, and the signal is at a low level, D2
Digits are not displayed.

When displaying the D2 digit, a digit drive signal is input to the D2 digit, but the same waveform as described above is obtained, only that the period of the segment signal shown in C and d becomes longer.

The above example was shown for liquid crystal, but the same way of changing the electrode connection can be applied to other devices other than liquid crystal, such as electrochromism,
The same applies to PLZT and the like, and the drive method for display is different for each display block depending on the drive method that is optimal for each element.

As explained in the example above, when the amount of information increases, in order to reduce the scale of watch hardware and reduce watch costs, static display and matrix display blocks are used on a single display panel. and display under the optimal driving conditions for each block.

[Brief explanation of drawings]

FIG. 1 is a block diagram according to the present invention, FIG. 2 is a diagram showing a clock display panel, FIG. 3 is a drive and display block diagram, FIG. 4 a is a matrix configuration diagram, and FIG. 4 b is a static configuration diagram.
FIG. 5 is a static display drive waveform diagram, FIG. 6 is a matrix display drive waveform diagram, and FIG. 7 is a block diagram of the present invention.
FIG. 8 is a block diagram of the present invention, and FIG. 9 is a second/day display drive waveform diagram. 15...Common electrode 1, 16...Common electrode 2, 33...Logic mechanism 1, 34...
Logic mechanism 2, 35... Clock display panel, 72... Boost mechanism 1, 73... Voltage conversion mechanism 2, 81... Operation mechanism.

Claims (1)

[Claims] 1. In an electronic watch having an electro-optical display device such as a liquid crystal, electrochromism, light emitting diode, etc., the electro-optical display device is statically driven from a numeral display block and a matrix. Furthermore, the number display block is configured to display time information consisting of at least hours and minutes, and the second display block is configured to display time information other than hours and minutes. An electronic clock characterized in that it is configured in a manner that it displays information on the screen.