Sojiro Hagihara

Title: Sojiro Hagihara: Innovator in Plasma Display Technology

Introduction

Sojiro Hagihara is a notable inventor based in Yokohama, Japan. He has made significant contributions to the field of plasma display technology, holding three patents that showcase his innovative approach to improving display apparatuses.

Latest Patents

Hagihara's latest patents include a plasma display apparatus and a method of driving the same. This patent describes a PDP apparatus featuring a driving circuit that incorporates a circuit for applying a rising-slope waveform during a reset period, a circuit for applying a falling-slope waveform, and a clamp circuit designed to generate a falling waveform with a dulled transition between the two waveforms. The clamp circuit utilizes a bidirectional switch with two FETs, and a gate feedback circuit is connected to the gate portion of the FET at the panel side. This innovation effectively reduces current noise in the sustain electrode across the panel, addressing issues such as increased radiation and stress on components like FETs.

Another significant patent is for a plasma display device that includes connecting means for linking the X/Y electrodes of the plasma display panel with the X/Y electrode drive circuits. In this design, the current path connecting the center electrodes of the plasma display panel to the drive circuits is longer than that connecting the peripheral electrodes. The current paths are arranged in a U-shape, folded at the upper and lower parts of the plasma display panel, ensuring efficient connectivity.

Career Highlights

Hagihara has worked with prominent companies in the technology sector, including Fujitsu Hitachi Plasma Display Limited and Hitachi, Ltd. His experience in these organizations has allowed him to refine his expertise in plasma display technology and contribute to advancements in the field.

Collaborations

Throughout his career, Hagihara has collaborated with notable colleagues such as Akihiro Machida and Takashi Shiizaki. These partnerships have fostered a creative environment that has led to innovative solutions in plasma display technology.

Conclusion

Sojiro Hagihara's contributions to plasma display technology through his patents and collaborations highlight his role as a key innovator in the field. His work continues to influence advancements in display technology, showcasing the importance of innovation in this rapidly evolving industry.