Waltham, Mass.-based Thermo Electron Corp. announced that the shareholders of its Thermo Vision Corp. and ThermoSpectra Corp. have approved the mergers of the companies into its public subsidiary, Thermo Instrument Systems Inc. Under terms of the agreement, shareholders of Thermo Vision will receive $7 in cash per share, and holders of ThermoSpectra will receive $16 per share. Thermo Vision designs and manufactures optical components, sensors and imaging systems. ThermoSpectra produces instruments for imaging, inspection, measurement and temperature-control applications.