Coherent Inc., a developer of photonics technology for the commercial and scientific research markets, has added Lawrence Tomlinson, former senior vice president and treasurer of Hewlett-Packard Co., to its board of directors. He is currently a director of Salesforce.com.   . . .   DALSA Corp. has received an order for high-performance digital cameras totaling more than $1.5 million. The cameras are expected to be delivered to the customer this year, with the potential for additional orders in 2004. The order was placed by a producer of capital equipment for the semiconductor manufacturing industry; DALSA said the cameras will be the "electronic eyes" in inspection systems and will help wafer manufacturers maintain better process quality and control, improve yield and lower costs.   . . .   Precision optics manufacturer Nikon Instruments Inc. has entered into a cooperative marketing agreement with Solent Scientific, manufacturers of full-enclosure incubation chambers for microscopes. Nikon said its US dealers will offer the Nikon Eclipse TE2000 inverted research microscope and Solent Scientific's 37-degree incubation chamber as a complete live cell microscopy solution.