Active-Matrix Addressed VFD Kanji Character Display

Abstract

A Kanji character display was investigated with 5mm square character size.
The display's active substrate is designed by C-MOS technology to introduce the inverter structure as the driver. This structure requires a resistive-sea to prevent surface charging, however, it achieved normal phosphor lighting and relieved the transistor from severe off-current.
The pull-down voltage value was determined by deliberating the turn-off characteristic of active-matrix addressed VFD, which in turn suggested that no exclusive power supply is required.
The device is accessed only with 43-pins by incorporating S-RAM and direct-acess-driving.
The C-MOS structure consumes less power and performs about 3000 cd/m² with a 25V drive. The variation degree of its brightness versus ambient temperature is half that of conventional VFDs.
A hybrid display representing Kanji character and fixed pattern was realized by die-bonding the silicon chip, in addition to fixing the phosphor pattern.