In this case, it is not primarily a matter of supply and demand, though that may enter into it a bit. Just before the quake, the Japanese Yen hit an all time historic high against the rest of the world's currencies. The effect was fairly minimal here, since the Canuck-buck is also very strong at the moment. It hit the US hard, since their greenback is weak. The more ethical stores continued to sell at the prior prices while inventory existed, but had to raise prices when their wholesale prices took substantial jumps upon acquiring new inventory. This is not Nikon-specific nor Sendai specific. All Japanese goods from cameras to cars to consumer electronics are subject to currency fluctuations.
At the moment the the Bank of Japan is "liquefying" the Japanese money supply. Some would say "printing money", in order to have cash to pay for recovery. This should eventually cause inflation, and then the relative value of the Yen should drop. However, monetary dynamics are not necessarily predictable, since every currency in the world is involved. A strengthening or weakening Euro due to Ireland, Spain, Portugal and Greece monetary problems, or France/Germany actions to counteract the situation, could tip the balance substantially and unpredictably. The US is struggling with ongoing recession that began with the economic crisis of 2008, while Canada barely felt the effect in comparison. To a great extent the economic boom in my province, (we have more documented petroleum reserves now just in this province, than Saudi Arabia) has been towing the rest of the country.
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