PASADENA, Calif., Nov. 10 -- SpectraSensors Inc. has received $4 million in equity financing from Forrest, Binkley & Brown, a venture capital firm based in Newport Beach, Calif. and The United Company, located in Bristol, Va. The funds will be used for expanding the manufacturing and marketing of our gas sensor products and to develop an absolute wavelength reference product and a widely tunable laser for optical communications, said Randy May, co-founder of SpectraSensors.The company's technology is used to enhance dense wavelength division multiplexing systems, which bundle multiple wavelengths into a single fiber, by providing a variety of wavelengths from a single laser and thereby eliminating the need for inventories of specific wavelength lasers, the company said. The wavelength reference product allows the widely tunable laser to be set to a specific communications channel.