Carl W. Hull is resigning as CEO of Applied Imaging Corp., a San Jose, Calif., supplier of automated imaging and image analysis systems used in genetics and pathology laboratories for the analysis of chromosomes and molecular markers. His resignation will be effective Dec. 31. Robin C. Stracey, president and COO, will become president and CEO effective Jan. 1. Hull will remain on the board of directors. Stracey joined the company in 2003. Before that, he was vice president and general manager of a chromatography and mass spectrometry business unit at Thermo Electron Corp.    . . .    IPG Photonics Corp., of Oxford, Mass., announced today that Multitorch GmbH is using its one-kw fiber laser for deep penetration welding of spark plugs into its production line. Multitorch, of Sinsheim, Germany, has welded more than 25,000 spark plugs since it began using the high-power laser several months ago. The fiber laser achieved a penetration depth of more than 2.5 mm in highly alloyed steel at 1-kW output power with a 100-µm fiber. Multitorch's prechamber spark plug is a new approach to improving lean burn gas engine operation. The ignition electrode is arranged inside a small prechamber with five orifices. After spark ignition, a rapid combustion in the prechamber generates five torch jets, which boost the main combustion process of the engine with high power; the spark plug acts as an amplifier of ignition energy.    . . .    RPMC Lasers, an O'Fallon, Missouri-based distributor of multimode laser diode products, has been selected as the North American distributor for Bright Solutions, an Italian maker of nanosecond and red/green/blue CW OEM diode-pumped lasers and OEM fiber-coupled laser diode products. RPMC will demonstrate Bright Solutions products at Photonics West, Jan. 25-27 in San Jose, Calif. The company also sells LDX Optronics laser diodes, is the North American manufacturer's representative for Lumera Lasers picosecond lasers and handles sales and marketing for JP Innovations LLC, a manufacturer of custom solid-state laser systems.