Ion Optics Inc. of Waltham, Mass., has announced that it is developing a chip-based IR gas sensor that will be manufactured using microelectromechanical systems (MEMS) technology. The company expects that the device, known as SensorChip, will offer competitive sensitivities in a smaller and more economical package. Ion Optics, which presented the SensorChip at the Micromachined Devices and Components conference in Santa Clara, Calif., in September, will initially focus its development efforts on the detection of hydrocarbons, CO2 and H2O. SensorChip is in a prototype evaluation phase.