Simply to give an idea of the status of Canon manufacturing plants in Japan, I share with you the press release from the red-branded company: No manufacturing is planned in the Canon plants on March 14th. There will probably be some production starts in the week, but several plants (including the one in Fukushima Prefecture) will not restart before several days.
Reasons are not precisely described but the local priorities are certainly elsewhere, with the gigantic issues of rescue, transportation and logistics that are filling the minds and using the energy of everybody in this part of the world.
Source: Canon.
Update:
Very similar announcement have also been made by Nikon which is still evaluating the possibility to restart its plants and the long-term rationing of electricity from this week.
Source : Nikon.