MANUFACTURING METHOD OF TORSION BAR, VIBRATION ELEMENT, OPTICAL SCANNER, AND IMAGE FORMING APPARATUS AND IMAGE PROJECTION DEVICE USING THE SAME

摘要

PROBLEM TO BE SOLVED: To make a manufacturing time of a torsion bar shorter than before.SOLUTION: A substrate material 500 made of metal or metal alloy is machine worked to form a torsion bar 31. A processing surface 400 of the torsion bar 31 is subjected to surface treatment to be smoothened. The present invention in which the torsion bar 31 is formed by machine work can reduce a manufacturing time of the torsion bar 31 compared to the prior art in which the torsion bar 31 is formed only by etching. Further, since the processing surface 400 of the torsion bar 31 is subjected to surface treatment to be smoothened, roughening that occurs on the processing surface 400 after working processing of metal or metal alloy can be alleviated.