Z-90 hardlight shield
From Halopedia, the Halo wiki
The Z-90 Photonic Coalescence Emitter/Aegis (Z-90 PCE/A) more commonly known as the Hardlight Shield, is a Forerunner anti-personnel shielding system. Like other examples of hard light technology, it works by using a photon emitter to fuse light particles into a dissipative barrier.
Hardlight shields are frequently employed by the ground forces of the mechanical Prometheans, with Watchers providing different types of shield for Knight and Crawlers in combat, and Promethean Soldiers using them on their own. This technology has been adapted for use with the MJOLNIR Powered Assault Armor, allowing Spartans to use the shield to protect themselves from incoming fire. While using the Hardlight Shield, a Spartan is unable to use weapons, and the MJOLNIR's energy shields are prevented from recharging until the Hardlight Shield dissipates.
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