3 ms·
It can't actually harm your hearing, by definition. Hearing damage caused by high intensity sound is the result of mechanical transduction of sound waves to ha
by etrautmann 13y ago
It can't actually harm your hearing, by definition. Hearing damage caused by high intensity sound is the result of mechanical transduction of sound waves to hair cells in your inner ear. When the amplitude of a certain frequency is too high, the cells responsible for turning those mechanical vibrations into electrical signals are physically damaged.
Ultrasound is mechanically filtered, so it can't propagate into your cochlea and damage the hair cells. This is in contrast to something like photons, where UV or infrared light can absolutely damage your photoreceptors in your eye.
- marshray 13y agoNo filter has an infinitely steep cutoff slope, it's a question of the 'degree' of attenuation. It may or may not be safe in practice, but if it is it's not "by definition". 50KHz is just two octaves above our normal range of hearing. She's claiming "charge laptop in 3.5 hours" levels of power transferred to a transducer "the size of a flash drive" a useful distance away. Now apply the inverse square law to estimate the necessary output power or assume a focused beam. Now imagine that flash drive is your ear, your eyeballs, or a pregnant lady.