MIDDLEFIELD, Conn. (AP) ¿ Zygo Corp., maker of optical components and fiber optic network modules, reported Thursday that it suffered a $47.4 million fiscal 2009 fourth-quarter loss, compared with a small year-ago profit, as revenue plunged 50 percent. The loss in the quarter was equivalent to $2.81 a share, compared with a profit of $1.1 million, or 6 cents a share, a year earlier. The loss included charges related to asset impairment, write-downs and reserves on various other balance sheet items. Zygo cited the economic downturn, recent changes in its business strategy and operations, and the resulting revaluation of some of the company's assets. Revenue in the quarter fell to $24.2 million from $48.5 million in the same period a year earlier. Analysts surveyed by Thomson Reuters, who generally exclude one-time items from their estimates, were expecting a loss of 17 cents a share. Zygo shares rose 1 cent to $6.39 in Thursday trading during the regular session. Its shares fell 70 cents, or 11 percent, to $5.69 in after-market extended trading.