title: High-resolution photoacoustic imaging with focused laser and ultrasonic beams.
abstract: We report a photoacoustic imager that utilizes a focused laser beam in combination with a 20 MHz ultrasound focusing transducer to obtain micron-resolution tissue images over a long working distance. The imager is based on a ring transducer that combines ultrasonic and laser beams collinearly and confocally in a monolithic element. The combination of focused laser beam and short pulse irradiation led to significant improvement in lateral and axial resolutions compared to the pulse-echo ultrasonic imaging technique or photoacoustic imaging with an unfocused laser. Potential applications include clinical examination of the eye and characterization of thin and superficial tissues.
authors.forename: Fanting
authors.initials: F
authors.lastname: Kong
authors.forename: Y C
authors.initials: YC
authors.lastname: Chen
authors.forename: Harriet O
authors.initials: HO
authors.lastname: Lloyd
authors.forename: Ronald H
authors.initials: RH
authors.lastname: Silverman
authors.forename: Hyung Ham
authors.initials: HH
authors.lastname: Kim
authors.forename: Jonathan M
authors.initials: JM
authors.lastname: Cannata
authors.forename: K Kirk
authors.initials: KK
authors.lastname: Shung