RFQ/Demo
Application Brief

Laser Q-Switch & Pockels Cell Timing

Precise gate and delay timing for flashlamp, Q-switch, and Pockels cell sequencing in pulsed and ultrafast laser systems.

Application Brief · Pulse & Delay Generators
Model 575 pulse/delay generator benchtop front panel

The Mission

A pulsed solid-state laser is a sequence of timed events. The flashlamp or pump diodes fire, the gain medium builds up energy, and then the Q-switch opens to dump that energy into a short, high-peak-power pulse. Adding a Pockels cell for pulse picking or cavity dumping adds another gate that has to open and close on a tight schedule. Get the delays right and the laser runs clean. Get them wrong and you lose energy, stability, or the pulse entirely.

A pulse and delay generator owns that schedule. It sets the lamp-to-Q-switch delay, gates the Pockels cell driver, and triggers diagnostics and cameras, all referenced to one start pulse.

The Challenge

Timing here spans a wide range. The lamp-to-Q-switch delay sits in the tens to hundreds of microseconds, while the Pockels cell gate that picks a single pulse from a train can be only a few nanoseconds wide and has to land in a fixed window every shot. Low jitter keeps pulse energy repeatable. A fast, clean edge matters because the Pockels cell driver and Q-switch electronics trigger on that edge, and overshoot or ringing can cause a false or early gate.

Many labs also need adjustable-amplitude outputs to drive a specific trigger threshold, optical outputs to cross ground potentials in a high-voltage cage, and the ability to insert or remove a channel without re-cabling.

Q-switched laser timing sequence driven by one pulse and delay generator Timing diagram, not to scale. A single start trigger fires the flashlamp on channel A. After a programmed lamp-to-Q-switch delay of tens to hundreds of microseconds, channel B opens the Q-switch and the giant optical pulse is emitted. Channel C gates the Pockels cell pulse picker for a few nanoseconds around the output pulse. Start trigger (T₀) One start pulse references every delay Flashlamp drive · Ch A Channel A fires the flashlamp or pump diodes at T0 Q-switch gate · Ch B Channel B opens the Q-switch after the programmed lamp-to-Q-switch delay Pockels pick gate · Ch C Channel C gates the Pockels cell driver for a few nanoseconds Laser output The stored energy leaves as one short, high-peak-power pulse just after the Q-switch opens lamp-to-Q-switch delay: tens to hundreds of µs pick gate: a few ns wide time (not to scale)
Representative Q-switched laser sequence, with every delay referenced to one start trigger. Delays are illustrative and set per laser.

Recommended Berkeley Nucleonics Solutions

The Model 575 is built for exactly this work. It offers 2, 4, or 8 channels with 250 ps resolution and the deepest mix of output modules in the line, including TTL, adjustable high-voltage, and optical inputs and outputs, so you can gate a Pockels driver on one channel and fire a flashlamp on another while crossing potentials over fiber. The Model 577 covers the same ground in a full-featured 4 or 8 channel benchtop with rep rates to 20 MHz and channel-to-channel jitter below 50 ps RMS.

When the Pockels or pulse-picking gate has to be genuinely fast, the Model 765 delivers a 70 ps rise time (20 to 80 percent), 300 ps minimum width, 10 ps delay and width resolution, and around 4 ps RMS jitter, with adjustable amplitude up to 5 Vpp and an adjustable baseline offset. That edge speed drives a Pockels cell trigger with margin to spare. For a compact, lower-cost setup or a portable rig, the Model 525 packs six independent channels into a USB-powered, book-sized unit with 4 ns resolution.

Why It Works

These generators separate the slow and fast halves of the laser schedule onto independent channels referenced to one trigger, so the lamp-to-Q-switch delay and the nanosecond Pockels gate stay locked together shot after shot. Adjustable amplitude meets the trigger threshold of real driver electronics, optical I/O on the 575 keeps timing clean across high-voltage boundaries, and the 765 supplies the fast, low-overshoot edge a Pockels cell wants.

Getting Started

Berkeley Nucleonics application engineers help match channel count, edge speed, jitter budget, and output module to your timing diagram before you order. Send a block diagram or a short description of the events you need to synchronize, and we will return a configuration recommendation.

Email info@berkeleynucleonics.com or call 800-234-7858. Browse the full Pulse & Delay Generator documentation for datasheets, manuals, and ordering guides.