Ann Arbor, Mich., -based Kaiser Optical Systems Inc., a maker of volume phase holographic (VPH) diffraction gratings, announced that it has developed a proprietary high throughput (HT) process for VPH gratings for telecommunications and other industries which the company says will enable customers to design more compact, efficient and better performing systems. The gratings can be used for reconfigurable add/drop multiplexers (ROADMs) and wavelength selective switches as well as for multiplexers/demultiplexers, optical spectrum analyzers, optical channel monitors and tunable lasers.    . . .    Electronic Sensor Technology Inc., a provider of homeland security solutions based in Newbury Park, Calif., has appointed Beijing R&D Technology, based in China, as its exclusive distributor for zNose in that country. The zNose is an electronic sensor device that the company says can capture and analyze nearly any odor, fragrance or chemical vapor within 10 seconds. To date, Beijing R&D has placed five orders for the product for environmental and homeland security applications.    . . .    Precision Photonics Corp., a Boulder, Colo., -based manufacturer of optics with 1-nm tolerances for use in semiconductor manufacturing and the telecommunications, aerospace and biomedical fields, has received certification for the ISO 9001:2000 quality standard for its optical components and laser instrumentation. . . .    VisEn Medical, a developer of optical molecular imaging, today announced that Ed Kania, managing partner and chairman of Flagship Ventures, a venture capital firm, has joined its board of directors. Both companies are located in Cambridge, Mass. VisEn also announced that it has raised $4 million of additional venture capital financing, which it intends to use to support the commercial launch of its initial products later this year, and to develop additional applications of its technologies. VisEn's core technology platforms are designed to harness the power of optical imaging in vivo. The company's fluorescent molecular tomography system and optical probe portfolio use near infrared light to produce molecular maps of disease activities deep within the body and have applications in the areas of oncology, inflammation and cardiovascular disease in small animals used in research and preclinical studies.