Generation of low-divergence laser beams
Abstract
Apparatus for transforming a conventional beam of coherent light, having a Gaussian energy distribution and relatively high divergence, into a beam in which the energy distribution approximates a single, non-zero-order Bessel function and which therefore has much lower divergence. The apparatus comprises a zone plate having transmitting and reflecting zones defined by the pattern of light interference produced by the combination of a beam of coherent light with a Gaussian energy distribution and one having such a Bessel distribution. The interference pattern between the two beams is a concentric array of multiple annuli, and is preferably recorded as a hologram. The hologram is then used to form the transmitting and reflecting zones by photo-etching portions of a reflecting layer deposited on a plate made of a transmitting material. A Bessel beam, containing approximately 50% of the energy of the incident beam, is produced by passing a Gaussian beam through such a Bessel zone plate. The reflected beam, also containing approximately 50% of the incident beam energy and having a Bessel energy distribution, can be redirected in the same direction and parallel to the transmitted beam. Alternatively, a filter similar to the Bessel zone plate can be placed within the resonatormore »
- Inventors:
-
- 108 Independent Blvd., Aiken, SC 29801
- Issue Date:
- Research Org.:
- Savannah River Site (SRS), Aiken, SC (United States)
- OSTI Identifier:
- 868924
- Patent Number(s):
- 5245619
- Assignee:
- Kronberg, James W. (108 Independent Blvd., Aiken, SC 29801)
- Patent Classifications (CPCs):
-
G - PHYSICS G02 - OPTICS G02B - OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS
H - ELECTRICITY H01 - BASIC ELECTRIC ELEMENTS H01S - DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT
- DOE Contract Number:
- AC09-89SR18035
- Resource Type:
- Patent
- Country of Publication:
- United States
- Language:
- English
- Subject:
- generation; low-divergence; laser; beams; apparatus; transforming; conventional; beam; coherent; light; gaussian; energy; distribution; relatively; divergence; approximates; single; non-zero-order; bessel; function; comprises; zone; plate; transmitting; reflecting; zones; defined; pattern; interference; produced; combination; concentric; array; multiple; annuli; preferably; recorded; hologram; form; photo-etching; portions; layer; deposited; material; containing; approximately; 50; incident; passing; reflected; redirected; direction; parallel; transmitted; alternatively; filter; similar; placed; resonator; cavity; front; mirror; rear; axially; aligned; mirrors; inside; generate; source; interference pattern; axially aligned; laser beams; apparatus comprises; laser beam; light beam; light beams; beam energy; energy distribution; laser source; layer deposited; incident beam; reflected beam; coherent light; resonator cavity; apparatus comprise; gaussian beam; containing approximately; reflecting layer; axially align; low-divergence laser; conventional laser; /372/359/
Citation Formats
Kronberg, James W. Generation of low-divergence laser beams. United States: N. p., 1993.
Web.
Kronberg, James W. Generation of low-divergence laser beams. United States.
Kronberg, James W. Fri .
"Generation of low-divergence laser beams". United States. https://www.osti.gov/servlets/purl/868924.
@article{osti_868924,
title = {Generation of low-divergence laser beams},
author = {Kronberg, James W},
abstractNote = {Apparatus for transforming a conventional beam of coherent light, having a Gaussian energy distribution and relatively high divergence, into a beam in which the energy distribution approximates a single, non-zero-order Bessel function and which therefore has much lower divergence. The apparatus comprises a zone plate having transmitting and reflecting zones defined by the pattern of light interference produced by the combination of a beam of coherent light with a Gaussian energy distribution and one having such a Bessel distribution. The interference pattern between the two beams is a concentric array of multiple annuli, and is preferably recorded as a hologram. The hologram is then used to form the transmitting and reflecting zones by photo-etching portions of a reflecting layer deposited on a plate made of a transmitting material. A Bessel beam, containing approximately 50% of the energy of the incident beam, is produced by passing a Gaussian beam through such a Bessel zone plate. The reflected beam, also containing approximately 50% of the incident beam energy and having a Bessel energy distribution, can be redirected in the same direction and parallel to the transmitted beam. Alternatively, a filter similar to the Bessel zone plate can be placed within the resonator cavity of a conventional laser system having a front mirror and a rear mirror, preferably axially aligned with the mirrors and just inside the front mirror to generate Bessel energy distribution light beams at the laser source.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {1993},
month = {1}
}