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April 30

Tokyo Toilet smart glass defect

Hi all! I was looking through a machine translation of this press release PDF, which seems to indicate that the smart glass used for the walls of one of the toilet designs for the Tokyo Toilet project is locked into the opaque state during months where there's a drop in temperature. This document includes the word "Defects" in the URL, which I assume refers to this design only being operational during certain times of the year as a solution to some unspecified problem, but I'm struggling to find out why/how exactly the temperature affects this toilet's smart glass functionality. It's specifically tricky because trying to perform a cursory search on how temperature affects smart glass seems to mainly pull up info about passive thermochromic smart glass, but other articles and footage of the switch toggle have led me to believe that this is an active and electrically switchable smart glass setup, so unless I'm mistaken, that thermochromic info wouldn't be relevant here. Basically, I'm just looking for any leads as to what's going on here lol thanks! ~Helicopter Llama~ 16:14, 30 April 2024 (UTC)[reply]

Sounds like it's a cholesteric liquid crystal panel or something similar. These were briefly fashionable for electrically switchable opaque/transparent wall panels back in the 1990's. The company I worked for had it on one floor of their high rise head office. They were notorious for not working at low temperatures (< 10 C) and failing completely at high temperatures (> 35 C)

Another possibility is the method used in auto-switching variable darkening welding helmets - I don't know how they work, other than knowing they are battery powered and are controlled by a light sensor. ```` Dionne Court (talk) 02:12, 1 May 2024 (UTC)[reply]