Ultrasound generation from an optical fiber, based on the photoacoustic principle, could have broad applications, such as
ultrasound nondestructive test (NDT) and biomedical ultrasound imaging. There are many advantages of these fiber-optic
ultrasonic transducers, such as small size, light weight, ease of use, and immunity to electromagnetic interference.
This paper will demonstrate a novel structure which the ultrasound signal is generated on the sidewall of the fiber. Two
experimental configurations of the fiber-optic sidewall ultrasonic transducer are discussed. One is that a photoacoustic
material is directly coated on the sidewall of the optical fiber. The other one is that the photoacoustic material is directly
coated on an aluminum plate and the sidewall fiber is buried in the material. By using this novel sidewall ultrasound
generator, we can effectively generate ultrasound signal at multiple, particular locations along one fiber.