Method for control of electrochromic device

• US 9,335,602 B2
• Filed: 07/25/2014
• Issued: 05/10/2016
• Est. Priority Date: 07/25/2014
• Status: Active Grant

• Current Assignee: Redoxlens Company Limited
• Original Assignee: Tintable Kibing Co., Ltd.
• Inventors: Lai, Chien-He, Chung, Yi-Wen
• Primary Examiner(s): CHOI, WILLIAM C
• Application Number:
  US14/340,672
• Publication Number:
  US 20160026059A1
• Time in Patent Office: 655 Days
• Field of Search: 359265-275, 359/603, 359/604
• US Class Current: 1/1
• CPC Class Codes: B60R 1/088 using a cell of electrically changeable optical characteristic, e.g. liquid-crystal or electrochromic mirrors
• CPC Class Codes: C09K 9/00 Tenebrescent materials, i.e. materials for which the range of wavelengths for energy absorption is changed as a result of excitation by some form of energy
• CPC Class Codes: G02F 1/155 Electrodes
• CPC Class Codes: G02F 1/163 Operation of electrochromic cells, e.g. electrodeposition cells; Circuit arrangements therefor

Abstract

A method for control of electrochromic devices is revealed. First a duty cycle of PWM is changed to a preset Q value according to a signal detected by a detector while the electrochromic device is switched to the colored state. The Q value represents electric charge that corresponds to colored-state transmittance. Then turn off the PWM. Thus the response time for coloration and the transmittance of the electrochromic device are maintained within a preset range, without being affected by ambient temperature, setting time and aging of the materials used. Thus the electrochromic device is more convenient to use and having more practical value.

Claims

1. A method for control of electrochromic devices comprising the steps of:

changing a duty cycle of PWM to a preset Q value according to a signal detected by a detector while the electrochromic device is switched to colored state and the Q value represents electric charge corresponding to colored-state transmittance; and

turning off the PWM;

thereby response time for coloration and transmittance of the electrochromic device are maintained within a preset range;

wherein the Q value is calculated according to the following equation;

2. The method as claimed in claim 1, wherein the signal detected by the detector is selected from the group consisting of system temperature, current magnitude, and terminal voltage.