A GaAlAs diode laser [ 780 nm , 30 mW continuous wave ( CW ) , 0.785 cm ( 2 ) , 38.2 mW/cm ( 2 ) ] was applied in contact with four points perpendicularly to the skin over the carpal tunnel area for 90 sec per point ( 2.7 J , 3.4 J/cm ( 2 ) / point ) .