Generation of nearly nondiffracting Bessel beams with a Fabry–Perot interferometer

A new concept for generating zero-order Bessel beams was studied theoretically. The spatial intensity distribution was calculated numerically using a wave optics model. Approximate analytical expressions were derived to describe the radial intensity distribution in planes perpendicular to the optical axis of an imaging lens.Texas InstrumentsNational Science FoundationOTKA Foundation of the Hungarian Academy of Science

Work report - CIF and GooSBA projects

During the 10-week period in the IT-CERT team at CERN, two main projects were assigned and completed. The objective of the first project was to investigate the CIF (Collective Intelligence Framework) and decide how the functionality it provides could benefit the CERN infrastructure. The second project involved developing a tool for identifying potentially malicious HTTP and DNS traffic through URL verification using Google Safe Browsing API database. Both projects were completed on time and the results were submited to the supervisor, Remi Mollon

Classification of some protozoa found in Wilkinson\u27s swampages

The Department of Biological Sciences at Northern Illinois State Teachers College has made extensive use of Wilkinson\u27s Swamp for instruc­tional purposes. However, to date, little has been done in an attempt to identify the fauna of this area. There ere no available records regarding the protozoan population in this area. Preliminary observations indicated that protozoa were found in great abundance in the swamp. Identification of a all of the unicellular animals in the time allowed seemed impossible. However, It was felt that an attempt to classify as many of the protozoa as possible could be a challenging problem and might well serve as an im­petus for future study. The author has limited his work to the classifi­cation of nineteen species found in the swamp. The problem was carried out in five parts and will be discussed in this order. I. Location, History and Description of Swamp, II, Collecting the Protozoa, III. Culturing Protozoa, IV. Classifying Protozoa by Morphological and Physiological Characteristics, and V. Photographing those forms identi­fied

M2 Parameter of Multimode Laser Diode Beam Transformation in Real Asymmetric Optical Systems

Generalization of M2 parameter on the case of asymmetric, multimode laser beam and array of laser beams is proposed. The geometrical method of propagation of beams of this type in real asymmetric optical systems, not restricted to paraxial approximation, is presented. The quality of lens design destined to transform of this type beam is discussed and the appropriate criterion based on transformation of M2 parameter is proposed. The examples of application of this method to the problem of diode laser beam formation are presented and discussed.</jats:p

Bessel-Gauss Coherently Combined Beams

The application of a conical wavefront in the near field of the tiled aperture coherent beam combination (CBC) produces a “star-like” Bessel-Gauss irradiance pattern i.e. BG-CBC, in the far field. The properties of such a structured optical field were numerically investigated. In contrast to that for the classical CBC, the power diffracted beyond the first few BG-CBC rings is nearly homogenously distributed. Additionally, shaping the segmented conical wavefront can result in a significantly increased caustic length