Maskless plating has been achieved through a new technique that utilizes a cw or pulsed laser, focused onto an electrode in an electroplating bath. In the region of optical absorption on the cathode, plating enhancement rates on the order of 103 occur for optical power densities on the order of 104 W/cm2. Laser scanning produces a plating pattern along the scanning path. A qualitative theory based on convective mass transport is used to explain the results.

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Repetitive pulses from lasers with pulse widths 5–10 nsec or a current generator with 10–25-nsec widths have been used to launch acoustic waves by thermoelastic expansions. For the laser case, when transparent media such as quartz plates are used to acoustically constrain the energy absorbing surface, an increase of up to 46 dB at 20 MHz was observed over that generated from a free surface. An experiment using a scannable laser to generate elastic waves for flaw detection in a metallic sample is described.

Calorimetric and acoustic studies of the mechanism of pulsed laser ablation of a polymer at the wavelengths of 193, 248, and 308 nm are reported. The results are mutually consistent and provide insight into the ablation mechanism.