From Light to Sound

Researchers from the University of Michigan have created a device that can convert light waves to sound for better imaging. The device can open up new avenues with regards to terahertz range; the last frontier of the electromagnetic spectrum. Better known as T-rays, its frequencies can only be detected by specialized tools.

What researchers essentially did was convert light wave into ultrasound waves with the help of a newly developed transducer (device that converts light to sound). The terahertz gap falls in between the microwave frequencies we use for cooking food or phone signals and infrared bands of the electromagnetic spectrum which enable heat vision and colour the world. When the terahertz light hits the transducer, the nanotubes in it absorb the light and convert it into heat which then expands and creates an outgoing pressure wave or ultrasound wave.

The transducer is sensitive, compact and works at room temperature unlike current tools that need to be kept cold to operate. Scientists state that the speed and efficiency of the system could make it useful in the areas of weapon detection, security checks, studying solar system and imaging body tissues.