Berkeley Nucleonics Corporation 1-800-234-7858 The Use of Digital Delay Generators in Laser Induced Breakdown Spectroscopy Applications

Berkeley Nucleonics Corporationwww.berkeleynucleonics.com1-800-234-7858

The Use of Digital Delay Generators in Laser Induced

Breakdown Spectroscopy Applications


Digital Delay Generator

• Digital Delay Generator - a key component for LIBS applications– Precise timing between the laser and detector– Sets the duration of the detector gate– Sets the time between lasers – dual pulse– Determine the rate and number of pulses – multiple

pulse

Timing is a variable in every LIBS application and proper timing can greatly enhance the efficacy of a system.


Digital Delay Generator – What Does It Do?


Digital Delay Generator – What Does It Do?

It provides several different sets of timing pulses – each synchronized to one another


DDG Features

• The pulses:– Trigger and synchronize lasers– Delay and gate ICCDs– Delay and gate cameras and imaging

equipment


LIBS Applications

• The dynamics of the laser plume/plasma in LIBS determines the optimal time to take measurements1. The vapor plume expands after the laser, then2. Two shockwaves – in the background gas region and in

the vapor plume occur, then3. From a few µS to tens of µS, the plume experiences

radiative heat loss.• Dynamic changes occur with time• Bottom line – wavelength, type of sample, laser

energy, laser width, your detector configuration – all affect the optimal time to take a measurement


LIBS Applications

• One needs to adjust delays and gates to find the optimal settings – this is what a delay generator gives you


The Role of the Delay Generator

• Dual pulse methods have improved the limits of detection for many LIBS applications– Orthogonal and collinear methods have been

discussed in the literature– Differing energy levels for each laser is

indicated– In all cases the time between lasers is

adjusted for optimal results


Multi-pulse LIBS

• Multiple pulses from one laser or firing of several lasers – Low energy multiple pulses via a DDG burst– Sequencing several lasers with a single

detector via a multi-channel DDG


Berkeley Nucleonics Corporation

• BNC makes inexpensive delay generators that– Delay and gate ICCDs– Control the time between dual pulses and then delay

and gate the ICCD– Provide single triggers to multiple lasers– Provide multiple triggers to a single laser

• BNC has been making digital delay generators since 1973

Documents

Berkeley Nucleonics Corporation 1-800-234-7858 The Use of Digital Delay Generators in Laser Induced Breakdown Spectroscopy Applications