The photonic shield encloses the Vantelegary in a protective bubble of energy. The shield will last for a limited period of time as illustrated below by the white radial progress bar around it:
The shield protects the Vantelegary from almost all enemy fire. The exception are beam based weapons that cut through the photonic shield. The Vantelegary can carry up to 3 shields at any given time.
The shield may also be used as an offensive tool, by ramming enemy ships with it. This is demonstrated in the image below:
As you can see the Vantelegary is essentially turned into a ram, hitting and destroying enemy ships. The danger when doing this is that if you hit ships that are larger than the Vantelegary, you usually get wrecked. Also, mines cannot be destroyed like this.
NOTE: When ramming enemies with the photonic shield, pay attention to the progress bar showing you how much the shield lasts, hitting ships without the shield usually results in getting wrecked.
Damage: N/A.
Accuracy: N/A.
Reload method: Powerup pickup.
Use: pressing "Q" key.