We propose a technique for one-step micropatterning of as-grown carbon-nanotube films on a plastic substrate with sub-10 mu m resolution on the basis of the dry transfer process. By utilizing this technique, we demonstrated the novel high-performance flexible carbon-nanotube transparent conductive film with a microgrid structure, which enabled improvement of the performance over the trade-off between the sheet resistance and transmittance of a conventional uniform carbon-nanotube film. The sheet resistance was reduced by 46% at its maximum by adding the microgrid, leading to a value of 53 Omega/sq at a transmittance of 80%. We also demonstrated easy fabrication of multitouch projected capacitive sensors with 12 x 12 electrodes. The technique is quite promising for energy-saving production of transparent conductor devices with 100% material utilization.