Laser Firing Units

Product Description

The Laser Firing Units are lightweight units that provide fiber optic guided infrared radiation pulses to safely and reliably initiate many types of explosive and pyrotechnic output devices—deflagration, detonation, ignition, pressure and gas generators.

Our Laser Firing Units are immune to EMP, EMI and ESD. LFUs have built in test, low power demand and nearly unlimited distance between the fireset and ordnance. In applications where a positive physical barrier is required, initiation energy interruption is also available.

Our existing Laser Initiation systems have an integrated Built-in-Test (BIT) to ensure full end-to-end optical continuity and laser firing unit electrical functionality that is interfaced with flight telemetry. The LFU interfaces directly with the mission/flight computer via the missile system high speed bus.  This system offers significantly reduced weight and volume while offering increased system reliability and lower overall system cost.

Key Features

How Laser Firing Unit Works

Laser firing units (LFUs) are lightweight units that provide a means for safe initiation of ordnance devices. They also provide microwatt level built-in-test signals and detect the return from PSEMC laser initiated ordnance devices. The units are compact and lightweight, and have small power demand.

Ordnance devices can be initiated tens of meters from the LFU, using strong, lightweight fiber optic cables. Typical initiation times are less than 1 millisecond. All parts of the system are highly immune to electrostatic discharge and electromagnetic radiation.

PacSci EMC LFUs use fiber optic-coupled high-power laser diodes, one per initiated device, fully enclosed in a faraday cage. Electric power is transmitted into the faraday cage using patented Radio Frequency Attenuating Couplers (RFACs). Signals are transmitted into and out of the faraday cage using only optocouplers. Firing energy is transmitted to initiated devices via silica optical fibers. As a result, the laser diodes and their switching electronics are extremely well isolated from external electric and magnetic fields.

Built in test (BIT) is implemented by sending a very low power signal (less than 1% of the no-fire power of the ordnance devices) to the attached devices and detecting a partial reflection of that power returned over a separate fiber. A positive BIT indication is a certain evidence of the integrity of the firing fiber and connection to the ordnance device.



PacSci EMC LFUs are currently qualified and used on various missile defense programs. Our Laser Firing Units are currently in production and used on defensive missiles to defeat unfriendly missiles with warheads. LFUs support the critical mission of engaging and destroying in flight, with precision, high-speed ballistic missiles.


  • Firing Power Output
    Minimum 500 milliwatt, typical>1 watt
  • Pulse Duration
    10 to 13 milliseconds
  • Built In Test Power Output
    <100 microwatts
  • Operating Temperature
    -54 °C to +71 °C
  • Applicable Specifications
    Compliant with MIL-STD-1901B


Laser Firing Units may be customized to fit many customer envelopes.

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