Abstract:
Most of the whole-field optical methods for vibration measurement have low sensitivity when the points of the studied surface vibrate with the same amplitude. Those techniques also usually require complex and/or expensive solutions which are difficult to implement in engineering processes when the vibration amplitudes are relatively high. In order to overcome those limitations we propose a method for out-of-plane vibration measurement which uses structured light projection. The vibrating surface is obliquely illuminated by straight and parallel interference fringes produced by a Twyman Green interferometer with a 532-nm laser as light source. In order to enable fringe visualization two techniques were employed, namely, the phase modulation of the fringe pattern by using a vibrating mirror in the interferometer, and a stroboscopic illumination by using a Fabry-Perot etalon amplitude modulator. We demonstrated the technique by measuring the vibration amplitudes of small objects in the millimeter and submillimeter range.
Referência:
DIB, Luiz Felipe Gonçalves; HENRIQUE, Marlene Correa; SAITA, Marcelo Tadao. Vibration measurement by projection of phase-modulated and amplitude-modulated strucutred light. Journal of Applied Research and Technology, v.21, n.1, p.1-11, 2023.
Acesso ao artigo no site do Periódico:
https://jart.icat.unam.mx/index.php/jart/article/view/1076/950
