Twenty-three photonics companies from the Rochester, N.Y., region are exhibiting together in a New York State aisle at SPIE's Defense & Security Symposium (DSS) 2006, being held this week in Orlando. "The conference has doubled in size two years' running, and exhibitors will be waiting to see if the one-month change in timing will increase attendance," said Thomas Battley, executive director of the Rochester Regional Photonics Cluster and New York Photonics. Last year, the symposium was held the last week in March; this year, it is being held during the traditional spring break week. Rochester-area firms make up roughly half of the 45 companies participating from New York, the Rochester Business Journal reported.