title: Development of a Fiber Laser with Independently Adjustable Properties for Optical Resolution Photoacoustic Microscopy.
abstract: Photoacoustic imaging is based on the detection of generated acoustic waves through thermal expansion of tissue illuminated by short laser pulses. Fiber lasers as an excitation source for photoacoustic imaging have recently been preferred for their high repetition frequencies. Here, we report a unique fiber laser developed specifically for multiwavelength photoacoustic microscopy system. The laser is custom-made for maximum flexibility in adjustment of its parameters; pulse duration (5-10 ns), pulse energy (up to 10 μJ) and repetition frequency (up to 1 MHz) independently from each other and covers a broad spectral region from 450 to 1100 nm and also can emit wavelengths of 532, 355, and 266 nm. The laser system consists of a master oscillator power amplifier, seeding two stages; supercontinuum and harmonic generation units. The laser is outstanding since the oscillator, amplifier and supercontinuum generation parts are all-fiber integrated with custom-developed electronics and software. To demonstrate the feasibility of the system, the images of several elements of standardized resolution test chart are acquired at multiple wavelengths. The lateral resolution of optical resolution photoacoustic microscopy system is determined as 2.68 μm. The developed system may pave the way for spectroscopic photoacoustic microscopy applications via widely tunable fiber laser technologies.
authors.affiliation: Department of Physics, Bogazici University, 34342, Istanbul, Turkey.
authors.forename: Esra
authors.initials: E
authors.lastname: Aytac-Kipergil
authors.affiliation: Department of Physics, Bogazici University, 34342, Istanbul, Turkey.
authors.forename: Aytac
authors.initials: A
authors.lastname: Demirkiran
authors.affiliation: Department of Physics, Bogazici University, 34342, Istanbul, Turkey.
authors.forename: Nasire
authors.initials: N
authors.lastname: Uluc
authors.affiliation: Institute of Materials Science and Nanotechnology, Bilkent University, 06800, Ankara, Turkey.|FiberLAST, Inc., 06800, Ankara, Turkey.
authors.forename: Seydi
authors.initials: S
authors.lastname: Yavas
authors.affiliation: Department of Physics, Bogazici University, 34342, Istanbul, Turkey.
authors.forename: Tunc
authors.initials: T
authors.lastname: Kayikcioglu
authors.affiliation: FiberLAST, Inc., 06800, Ankara, Turkey.
authors.forename: Sarper
authors.initials: S
authors.lastname: Salman
authors.affiliation: Department of Electrical and Electronics Engineering, Bilkent University, 06800, Ankara, Turkey.|Lumos Laser, Ltd., 06500, Ankara, Turkey.
authors.forename: Sohret Gorkem
authors.initials: SG
authors.lastname: Karamuk
authors.affiliation: Department of Electrical and Electronics Engineering, Bilkent University, 06800, Ankara, Turkey.|Department of Physics, Bilkent University, Ultrafast Optics and Lasers Group, 06800, Ankara, Turkey.
authors.forename: Fatih Omer
authors.initials: FO
authors.lastname: Ilday
authors.affiliation: Department of Physics, Bogazici University, 34342, Istanbul, Turkey.
authors.forename: Mehmet Burcin
authors.initials: MB
authors.lastname: Unlu