Citizen Watch Company, Ltd.

Kouhei Kawanobe

Hiroshi Ogawa

Minoru Natori

Toshikazu Hatuse

Fukuo Sekiya

Toshikazu Shimazaki

Heihachiro Ebihara

Katsuo Nishimura

Singo Ichikawa

Toshiaki Oguchi

Tadahiko Nakagiri

Misao Uchino

Hisao Yamagata

Ryo Namiki

Yoshinobu Kashima

Kunihiro Daigo

An electronic calculator watch which comprises timekeeping means composed of an oscillator, a frequency divider connected to the oscillator, a counter circuit connected to the frequency divider, and a driver circuit connected to the counter circuit for providing an output signal indicative of time information, and calculating means composed of an oscillator circuit and a calculation circuit responsive to perform calculations under control of numerical inputs furnished by external operation device provided on a watch case. The watch also comprises a display including a first display section connected to the driver circuit of the timekeeping means to display the output signal delivered therefrom, and a second display section connected to the calculating means to display the result of calculations, each of the first and second display sections having a plurality of digit electrodes and a plurality of segment electrodes arranged in a matrix configuration.

Electronic calculator watch

A switch structure for an analog quartz crystal timepiece having a watchglass plate, a time dial to display time in an analog mode, and a digital display device, which switch structure comprises a plurality of transparent electrically conductive electrode films provided on the watchglass plate at positions corresponding to numerical display indicia on the time dial to permit generation of input signals corresponding to the numerical display indicia, respectively.

Switch structure for electronic timepiece

A driver circuit for an electrochromic display device which includes segment electrodes and a common electrode. The driver circuit has a power source, switching means connected between the power source and the segment electrodes, and circuit means disposed between the common electrode and the power source. The circuit means is operative to couple the common electrode to either a positive terminal or a negative terminal of the power source, whereby an electric current will flow through the segment electrodes in bleaching and coloring directions with the use of a single power source.

Driver circuit for electrochromic display device

A method and apparatus for driving an electrochromic display device in which an electric current is applied only to one of display elements for which non-coincidence exists between an initially applied display information signal and a subsequently applied display information signal. In one preferred embodiment, a driver circuit comprises a latch circuit for storing a display information signal, a non-coincidence detection circuit for detecting non-coincidence between a subsequently applied display information signal and an initially applied display information signal stored in the latch circuit, and a signal generating circuit responsive to a non-coincidence signal from the detection circuit for generating an output signal for a display element for which non-coincidence is detected. In another preferred embodiment, a driver circuit comprises a latch circuit for generating an output at the instant delayed from a display information signal, and gate means for generating an output signal in response to the display information signal and the output from the latch circuit.

Method and apparatus for driving electrochromic display device

Growing community of inventors

Kawagoe, Japan

Kouhei Kawanobe