Second Sight Medical Products Inc. has appointed Will McGuire to become the company’s new chief executive starting Aug. 18. The Sylmar biotech, which makes a system with an implant and camera mounted on eyeglasses to provide sight for blind patients, said its current Chief Executive Robert Greenberg will become chairman of the board, replacing billionaire Alfred Mann, who will become chairman emeritus. Mann, who helped develop the insulin pump and cochlear hearing aid, founded Second Sight in 1998, with Greenberg serving as chief executive since the inception. Mann owns about 33 percent of the stock and Greenberg owns about 3 percent. McGuire joins Second Sight from Volcano Corp., a heart imaging company in San Diego. Volcano was acquired by Royal Philips in February. Previously. McGuire was chief executive at AtheroMed Inc., a venture capital-backed company that developed arterial clearing devices, and chief operating officer at Spectranetics Corp., a publicly traded medical device company. Shares closed down 69 cents or 4.4 percent to $15.04 on the Nasdaq.