A new triangular-shape designed tool as a cathode in microelectromechanical etching process is a precision nanoscale production of a reclamation system of Indium tin oxide (ITO) thin-films defects removal from optoelectronic flat panel displays’ color filter surface is demonstrated in the current study. Through the ultra-precise removal of the thin-film nanostructure, the optoelectronic semiconductor industry can effectively reclaim defective products, reducing production costs. In the current experiment, a large size triangular shape cathode is accompanied by a small gap-width between the cathode and the workpiece takes less time for the same amount of ITO removal. A higher feed rate of displays’ color filter or a small end radius of the cathode combined with enough electric power produces fast machining. Pulsed direct current can improve the effect of dregs discharge and is advantageous in association with a fast workpiece feed rate. However, it raises the current rating. A large flow rate of the electrolyte corresponds to a higher removal rate for the ITO nanostructure. The electrochemical etching just needs a short time to make the ITO remove removal easy and clean.