White Papers

The following white papers describe various applications of VBG® technology:

 General White Papers and Product Information

     Overview of a novel WDM (wavelength division multiplexer) filter technology based on PD-LD’s proprietary VBG® technology.

    Describes applications for NIR spectroscopy in assessment of corrosion of concrete in bridges and infrastructure using PD-LD’s proprietary VBG® technology.

Abstract: Concentration of chloride ions was determined with a classical chemical titration method in three types of samples: a cracked concrete core and an undamaged concrete core, both taken from a bridge in Iowa, and also from concrete test samples prepared at Rutgers University. Chloride concentration profiles were obtained. The same samples were the subjected to the near infrared spectrometric determinations of chloride content by two manufacturers of spectrometric instruments. Very good correlation between the chemical and spectrometric measurements was obtained [ R2> 0.96], thus opening the possibility of rapid on-site chloride concentration determination in concrete structures.

    Describes a novel approach for achieving wavelength stabilization and wavelength agility in high-power two-dimensional stacks of high-power laser diodes through the use of VBG gratings with a Bragg period that varies as a function of spacing between the laser diode bars within a stack.  

    This paper, written jointly with MIT’s Lincoln Laboratory, describes a method of scaling power and brightness from diode arrays and stacks by wavelength beam combining (WBC) using a wavelength-chirped volume-Bragg grating (VBG®)

     Description of a wavelength multiplexer design that employs multiple transmission volume Bragg gratings written in the same region of a photosensitive glass having a through channel loss of <0.5dB.

   Describes a method of scaling the spacial brightness from commercial off-the-shelf laser diode stacks through wavelength beam combining, by use of a linearly wavelength-chirped Volume Bragg grating.

   Discusses spectral line narrowing and stabilization of the emission wavelength of multimode high-power laser diodes and arrays by use of volume Bragg gratings fabricatedin high-stability inorganic photorefractive glass. 

    This article provides an introduction to Volume Bragg Grating ®technology, and describes the advantages that VBG®s confer when used to stabilized high-power laser diodes.