Clifford Brockmyre has resigned as president and CEO of Infinite Group Inc., a developer of laser material processing, advanced manufacturing and laser and photonic technology. Brockmyre will remain as chairman of the board of directors and will focus on the management of Laser Fare Inc., the company's wholly owned subsidiary. Michael Smith was appointed interim president and CEO. Infinite also announced it will move its corporate headquarters from Rhode Island to Rochester, N.Y. Laser Fare's offices and operations will remain in Smithfield, R.I. . . .   Jonathan Mann has joined DRS Technologies Inc. as corporate counsel at its Parsippany, N.J., headquarters.