The suitability for low-coherence interferometry of a high-power, semiconductor laser line source operated at a forward bias current below threshold is demonstrated. Measurements of the important characteristics of the source are presented. For example, the source produces an output power of 1.3 mW and a spatially uniform coherence length of 16 mum at a bias current of 86% of threshold (250 mA) at 20 degreesC. The usefulness of the source is verified by measurement of the Line profile of a contact lens. (C) 2001 Optical Society of America. OCIS codes: 140.2010, 120.3180, 110.1650, 120.6650.