High‐performance acoustic microscope

Atalar, Abdullah
Hoppe, Marion
A commercial scanning acoustic microscope operating in the frequency range of 50–2000 MHz is described. It has a stable scan mechanism suitable for the high‐frequency end to give high‐resolution images and modes to allow for material characterization at the low‐frequency end. The high‐frequency electronics permitting a wideband operation with a variety of acoustic lenses are described. Microprocessors control many parts of the the instrument to release the user from the routine adjustments, resulting in a user‐friendly interface. Images are presented to show the resolution and penetration abilities of the instrument at several frequencies, along with comparative optical images
Review of Scientific Instruments


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High power microsecond fiber laser at 1.5 μm
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© 2020 Optical Society of America.In this work, we demonstrate a single frequency, high power fiber-laser system, operating at 1550 nm, generating controllable rectangular-shape μs pulses. In order to control the amplified spontaneous emission content, and overcome the undesirable pulse steepening during the amplification, a new method with two seed sources operating at 1550 nm and 1560 nm are used in this system. The output power is about 35 W in CW mode, and the peak power is around 32 W in the pulsed mod...
Citation Formats
A. Atalar and M. Hoppe, “High‐performance acoustic microscope,” Review of Scientific Instruments, pp. 2568–2576, 1986, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/52050.