Continuous-relief diffractive microlenses for laser beam focusing

Diffractive beam splitter for laser Doppler velocimetry.

A miniaturized sensor head for the optical measurement of velocities of fluids based on laser Doppler velocimetry is demonstrated. Holographic optical elements mounted on a glass substrate are used for beam splitting and deflection. Volume holograms in dichromated gelatin exhibit good optical efficiency (75% transmission of a cascade of two holographic optical elements). With diffractive device...

Diffractive nanoslit lenses for subwavelength focusing

Laser Beam Hazard for flight personnel

Lasers can produce a beam of light of such intensity that permanent damage to human tissue, in particular the retina of the eye, can be caused instantaneously, even at distances of over 10 km. At lower intensities, laser beams can seriously affect visual performance without causing physical damage to the eyes; causing transient damage or causing sensation and loss of focus. Laser illumination o...

Photonic-based laser driven electron beam deflection and focusing structures

We propose a dielectric photonic structure for ultrafast deflection and focusing of relativistic charged particle beams. The structure is designed to transform a free-space laser beam into a deflection force that acts on the free particles with the same optical phase over a distance of travel that is much greater than the laser wavelength. The proposed structure has a two-dimensional geometry a...

Focusing System Based on Chalcogenide Microlenses Attached to Optical Fibers

Arsenic chalcogenide microlenses (As2S3) produced by an original procedure have been used for focusing the red – infrared laser light direct through an optical fiber. The microlenses with diameter in the range 150 – 400 m were glued on the optical single-mode fiber ends by Canada balm under optical microscope. The focusing effect of the microlenses was investigated in a stereomicroscope, and th...