Isolating high-frequency vibrations in an improvised optical table using recycled tire interior

Abstract

Vibration isolation is essential for precision optical experiments, yet commercial optical tables remain prohibitively expensive for many institutions in developing regions. Here, we investigate the high-frequency vibrational response of a low-cost steel optical table mounted on a wooden support base, evaluating its suitability for laboratory use. Vibrations are induced using a speaker driven by sinusoidal signals sweeping from 200 Hz to 1580 Hz. The system's response is optically detected using a laser beam partially obstructed by a pinhole, with transmitted intensity measured by a photodetector and recorded via an oscilloscope. Analysis of the root mean square (RMS) voltage reveals distinct resonance peaks at 360 Hz, 780 Hz, 1160 Hz, and 1400 Hz, corresponding to structural modes of the complete system. Spectral mapping across the excitation sweep further indicates the presence of sidebands and modal coupling in the undamped configuration, suggesting complex vibrational behavior. To mitigate these effects, a recycled bicycle tire interior is introduced between the steel table and the wooden base as a passive damping element. Results show that the tire interior substantially reduces vibrational amplitudes and suppresses spectral complexity, leading to improved mechanical stability across the tested frequency range. This approach offers a practical and cost-effective vibration isolation strategy for resource-limited laboratories.