Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Experiment Video

Updated: Jun 16, 2026

Simultaneous Label-Free Autofluorescence Multi-Harmonic Microscopy
09:19

Simultaneous Label-Free Autofluorescence Multi-Harmonic Microscopy

Published on: August 29, 2025

Active autofocusing using an apertured Gaussian beam.

A Erteza

    Applied Optics
    |February 19, 2010
    PubMed
    Summary
    This summary is machine-generated.

    This study presents a novel autofocusing method for obscured Gaussian beams. The technique leverages spectral analysis of a dithered focus to achieve precise beam alignment on target.

    Related Concept Videos

    Atomic Force Microscopy01:08

    Atomic Force Microscopy

    Atomic force microscopy (AFM) is a type of scanning probe microscopy that can analyze topographic details of various specimens like ceramics, glass, polymers, and biological samples. AFM offers over 1000 times more resolution than the optical imaging system. Images generated from AFM are three-dimensional surface profiles, offering an advantage over the flat, two-dimensional images from other imaging techniques.
    The AFM Probe
    The probe is regarded as the heart of any AFM setup and comprises the...

    You might also read

    Related Articles

    Articles linked to this work by shared authors, journal, and citation graph.

    Sort by
    Same author

    Sparkle phenomenon.

    Applied optics·2010
    Same author

    Depth of convergence of a sharpness index autofocus system.

    Applied optics·2010
    Same author

    Boresighting a Gaussian beam on a specular target point: a method using conical scan.

    Applied optics·2010
    Same author

    Sharpness index and its application to focus control.

    Applied optics·2010
    Same author

    Numerical processing of dynamic subaperture testing measurements.

    Applied optics·1986
    Same author

    Pulsed laser beam control by hot spot tracking.

    Applied optics·1983

    Area of Science:

    • Optics and Photonics
    • Beam Control Systems
    • Metrology

    Background:

    • Accurate focusing of laser beams is critical for applications like material processing and optical sensing.
    • Obscurations in the beam path can degrade focusing performance and complicate alignment.
    • Traditional autofocusing methods may struggle with complex beam profiles or dynamic environments.

    Purpose of the Study:

    • To develop and present a robust method for autofocusing a Gaussian beam with obscuration onto a target.
    • To utilize the temporal spectra of a dithered focus for precise beam-target alignment.
    • To establish a closed-loop control strategy based on spectral properties of the reflected signal.

    Main Methods:

    • Employing a Gaussian beam source with a sinusoidally time-varying focus (dither).

    More Related Videos

    The Generation of Higher-order Laguerre-Gauss Optical Beams for High-precision Interferometry
    12:14

    The Generation of Higher-order Laguerre-Gauss Optical Beams for High-precision Interferometry

    Published on: August 12, 2013

    Femtosecond Laser Filaments for Use in Sub-Diffraction-Limited Imaging and Remote Sensing
    06:16

    Femtosecond Laser Filaments for Use in Sub-Diffraction-Limited Imaging and Remote Sensing

    Published on: April 25, 2019

    Related Experiment Videos

    Last Updated: Jun 16, 2026

    Simultaneous Label-Free Autofluorescence Multi-Harmonic Microscopy
    09:19

    Simultaneous Label-Free Autofluorescence Multi-Harmonic Microscopy

    Published on: August 29, 2025

    The Generation of Higher-order Laguerre-Gauss Optical Beams for High-precision Interferometry
    12:14

    The Generation of Higher-order Laguerre-Gauss Optical Beams for High-precision Interferometry

    Published on: August 12, 2013

    Femtosecond Laser Filaments for Use in Sub-Diffraction-Limited Imaging and Remote Sensing
    06:16

    Femtosecond Laser Filaments for Use in Sub-Diffraction-Limited Imaging and Remote Sensing

    Published on: April 25, 2019

  • Calculating the temporal spectra of the reflected signal under Fresnel approximations.
  • Analyzing phase and amplitude changes of specific spectral components near true focus.

    • Main Results:

    • Accurate calculation of temporal spectra is achievable for ranges validating Fresnel approximations.
    • Significant spectral component changes indicate passage through true focus.
    • Demonstrated feasibility of a closed-loop control strategy derived from spectral properties.

    Conclusions:

    • The presented method enables precise autofocusing of obscured Gaussian beams.
    • Spectral analysis of dithered focus provides a robust mechanism for beam alignment.
    • The derived closed-loop control strategy offers accurate and reliable beam focusing.