We demonstrate the use of a binary diffractive optical element in a very simple setup to convert the multilobed beam from a low fill factor array of coherent laser diodes into a quasi-Gaussian beam. The phase profile of the grating is determined with a phase retrieval algorithm. Experimentally, the conversion efficiency reaches more than 44%. We also establish that this setup can be used to mak...

1 EVTUHOV, v., and SIFGMAN, A. E.: ‘A “twisted-mode” technique for obtaining axially uniform energy density in a laser cavity’, Appl. Opt., 1965,4, pp. 142-143 2 DRAEGERT, D. A,: ‘Efficient single-longitudinal-mode Nd : YAG laser’, IEEE J . Quantum Electron., 1972, QE-8. pp. 235-239 3 SIP& D. L.: ‘Highly eflicient Nd : YAG laser end pumped by a semiconductor laser array’, Appl. Phys. Lett., 198...

A novel lens-array based illumination design for a compact co-registered photoacoustic/ultrasound transvaginal probe has been demonstrated. The lens array consists of four cylindrical lenses that couple the laser beams into four 1-mm-core multi-mode optical fibers with optical coupling efficiency of ~87%. The feasibility of our lens array was investigated by simulating the lenses and laser beam...

Nanoscale functional structures are indispensable elements in many fields of modern science. In this paper, nanopillar array with a pillar diameter far smaller than Abbe's diffraction limit is realized by a new kind of continuous wave (CW) laser direct lithography technology. With atomic force microscopy technology, the average diameter of nanopillars on thin OIR906 photoresist film is about 65...

Compared with single-focus optical-resolution photoacoustic microscopy (OR-PAM), multifocal OR-PAM utilizes both multifocal optical illumination and an ultrasonic array transducer, significantly increasing the imaging speed. A reflection-mode multifocal OR-PAM system based on a microlens array that provides multiple foci as well as an ultrasonic array transducer that receives the excited photoa...

There are a number of military and commercial applications for high-power laser systems in the mid-to-long-infrared wavelength range. By virtue of their demonstrated watt-level performance and wavelength diversity, quantum cascade laser (QCL) and amplifier devices are an excellent choice of emitter for those applications. To realize the power levels of interest, beam combining of arrays of thes...

We report the first experimental realization of four-channel DFB laser array with equivalent phase shift (EPS) based on the reconstruction-equivalent-chirp (REC) technique for CWDM systems. OCIS codes: (140.0140) Lasers and laser optics; (140.5960) Semiconductor lasers

A high-power multistripe diode-laser array has been used to pump miniature zigzag slab oscillators of Nd:YAG and Nd:glass. With Nd:YAG we have demonstrated output at 1.06 microm of 70-kW peak power and 585-mW average power with an electrical-to-optical efficiency of 4%. In this experiment the Nd:glass lasers were limited to 160-mW average power and less efficiency than the Nd:YAG. The differenc...