The human ear is one of the most sophisticated sound and vibration amplification systems. State-of-the-art laser doppler vibrometers reveal the vibrational characteristics of hearing mechanics. They provide ease of use and unsurpassed accuracy and resolution, revealing new dimensions in our understanding of hearing mechanics. Laser vibrometry is indispensable to those actively involved in the design, development, quality control, calibration and certification of middle ear implants.

The vibrational response of the tympanic membrane gives direct insight into the important causes of hearing loss, like stapes fixation or sclerotic changes in the ossicular chain. Laser doppler vibrometry allows for quick measurement of the frequency response providing excellent data to the audiologist.

Intensive medical, molecular and biomechanical research activities have provided much insight into the function of signal processing inside the ear. However, we are still far from a comprehensive understanding of hearing mechanisms. Current research deals with the details of electromechanical signal transduction occurring in the cochlea of the inner ear. For investigation of inner ear biomechanics, laser-doppler vibrometers have proven to be highly sensitive sensors that don’t affect the specimen.

Recently, finite element (FE) methods have been used in biomechanics to investigate and model components for medical applications. For example, to assist with bone surgery, various approaches to generating realistic bone models from computer tomography data are being  evaluated. A Polytec 3-D Scanning Vibrometer was used to determine for the first time the modal parameters of a pelvic bone and provided spatial vibration modes with an accuracy and resolution that was not possible before.

Laser-doppler vibrometers are widely used in industrial and engineering applications but their use for measuring system-level physiology is fairly recent. However, a large variety of internal sounds, pulses and vibrations can be detected simply by directing the laser beam at the body.