公开(公告)号：US10890791B2

公开(公告)日：2021-01-12

申请号：US16526197

申请日：2019-07-30

Applicant: TOPPAN PRINTING CO., LTD.

Inventor： Hiroshi Takahashi

IPC: G02F1/133 ,  H02M1/08 ,  H03K17/687

Abstract: A light control device includes: a light control element including a first layer stack and a second layer stack which include electrodes provided on base members, respectively, and a liquid crystal layer sandwiched between the first and second layer stacks; a switching element connected between an AC power supply and the light control element; a comparator that detects whether or not the AC power supply is higher than a first voltage that is higher than 0 V and is lower than a maximum value of the AC power supply; and a control circuit that performs PWM control or PFM control on the switching element if the AC power supply is higher than the first voltage.

公开(公告)号：US10971106B2

公开(公告)日：2021-04-06

申请号：US16599760

申请日：2019-10-11

Applicant: TOPPAN PRINTING CO., LTD.

Inventor： Hiroshi Takahashi

IPC: G09G3/36

Abstract: There is provided a liquid crystal optical modulation device which performs light control drive for a liquid crystal panel, the device including a voltage limiting section that limits a power supply voltage, which is applied to the liquid crystal panel from a commercial AC source, and a control section that controls a voltage applied to the liquid crystal panel through the voltage limiting section in accordance with a phase of the power supply voltage of the commercial AC source.

公开(公告)号：US20190353945A1

公开(公告)日：2019-11-21

申请号：US16526197

申请日：2019-07-30

Applicant: TOPPAN PRINTING CO., LTD.

Inventor： Hiroshi Takahashi

IPC: G02F1/133 ,  H03K17/687 ,  H02M1/08

Abstract: A light control device includes: a light control element including a first layer stack and a second layer stack which include electrodes provided on base members, respectively, and a liquid crystal layer sandwiched between the first and second layer stacks; a switching element connected between an AC power supply and the light control element; a comparator that detects whether or not the AC power supply is higher than a first voltage that is higher than 0 V and is lower than a maximum value of the AC power supply; and a control circuit that performs PWM control or PFM control on the switching element if the AC power supply is higher than the first voltage.