26th Annual Student Research Conference
Analysis of Normal Mode Patterns Using Holograms
Aric Pearson
Dr. Ian Lindevald, Faculty Mentor
A hologram is the result of interference of beams of light from a coherent light source that results in the production of a 3- dimensional image. Holographic Interferometry expands upon this idea, allowing for the visual analysis of vibrating systems. By analyzing the development of the holographic process, including non-vibrating holograms, the effects of coherence length and vibration, and correction for airflow and errors in reflective surfaces, we established a baseline for further experiments. Using both a 15mW and 30mW HeNe laser, we investigated the production of two-beam transmission holograms of objects vibrating at resonance frequencies. We produced holograms of objects using both time-averaged and real-time methods. Such holograms reveal normal mode shapes of the vibrating objects. The ultimate goal is to use these holographic techniques to image standing waves in air columns.
Keywords: laser, hologram, vibration, normal mode, interference, standing waves
Topic(s):Physics
Presentation Type: Oral Paper
Session: 206-5
Location: MG 1096
Time: 10:30