Paper
16 November 1999 Generation and industrial applications of hollow light cylinders
German Da Costa, Jose Cataldo, Rafael Guarga, Gabriel Usera, Arturo Lezama, Felix Mosqueda
Author Affiliations +
Abstract
A light beam structured as a hollow cone is obtained by oblique illumination of a cylindrical surface with a laser beam. The cylindrical surface may be a metallic needle or the core of an optical fiber. In the first case a speckle pattern appears around the light cone. The direction and mean length of light speckles are studied in the text. In the second case the light intensity distribution around the light cone presents bright and dark regions resulting from interference between light rays reflected from and passing through the fiber core. The hollow light cone is transformed into a hollow light cylinder (HLC) by means of a lens whose focus coincides with the cone vertex. The HLC is used to explore the cylindrical layer placed in the neighborhood of the internal wall of a combustion chamber model. Due to the large diameter of the model a Fresnel lens is used to transform the light cone into a light cylinder. This introduces additional optical noise in the system. The HLC is collected again by another Fresnel lens at the model output. A photodetector placed at the focus of the collected beam produces an electrical output showing pulses whenever residual particles pass through the explored region. A quantitative experimental analysis of the performance of the combustion chamber is thus performed.
© (1999) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
German Da Costa, Jose Cataldo, Rafael Guarga, Gabriel Usera, Arturo Lezama, and Felix Mosqueda "Generation and industrial applications of hollow light cylinders", Proc. SPIE 3835, Three-Dimensional Imaging, Optical Metrology, and Inspection V, (16 November 1999); https://doi.org/10.1117/12.370254
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Combustion

Light scattering

Scattering

Laser scattering

Fresnel lenses

Particles

Chemical elements

Back to Top