Optical profilometer with a standalone scanning sensor head

The use of compact disc (CD) pickups as distance sensors in optical profilometry is a well-established practice. The novelty of our device is the use of the built-in objective lens-tracking actuator of the pickup to perform a 1-D beam scanning of the sample. The profilometer prototype presented in this paper is made up of a standalone sensor-actuator optical head that can be easily positioned on samples of complex shapes with every orientation and can be operated by a remote control system. When 2-D scanning is unnecessary or even impossible, as for surface quality inspection of bulky mechanical pieces, a device that uses a CID pickup as both the sensor and the actuator is cheaper, faster, lighter, more compact, and more versatile than standard object-scanning setups that use xy translation stages. A lateral scan range of 800 mum and a vertical scan range of 160 mum are achieved. (C) 2001 Society of Photo-Optical Instrumentation Engineers.