What a weak dollar means to photonics
The conventional wisdom is that a falling dollar makes U.S. goods and services cheaper abroad, and foreign goods and services more expensive in the U.S. That is, it makes U.S. goods more competitive, and it deflates U.S. debt owed others as counted in foreign currency.
But many companies don't sell directly to companies abroad. A more complete downstream product may be exported by the customer's customer, but either way, the effect may be minimal--or at least obscure--to the photonics manufacturer.
Second, companies commonly import subcomponents from all over the world. A lower dollar then raises the cost to manufacture, erasing some or all of the advantages when it exports the complete product.
And, a lot of companies manufacture in the destination markets. This can help hedge against changes in currencies, among other things. In the example of Japanese blue-violet diode lasers, it changes the average prices and overall value, in dollars, that we assign to a market. But that can seem rather artificial when most of the Blu-Ray players are assembled in Asia anyway.
More often, the gains and losses from a falling dollar amount mostly to changes in market share: U.S. companies vs. non-U.S. companies, and U.S. importers vs. U.S. exporters.
For an explanation how a falling dollar is unlikely to create many new jobs in the U.S., read this article. It cites the reasons above, and notes that much of U.S. manufacturing is capital intensive, not labor-intensive. And, many manufacturers are small and not likely to ramp up hiring dramatically even if sales do improve.
Just the same, every little bit helps, especially if it means tipping a business from the red to the black or deeper into the black.