From Dragon Ball Encyclopedia, the ''Dragon Ball'' wiki
Perfect Cell curls his arms and legs together as he charges a purple aura around his body. He then brings them apart and expels a giant barrier around his body, capable of blocking certain attacks similar to the Super Explosive Wave.
Dragon Ball Z
Perfect Cell used this attack in his battle against Son Goku in his Full Power Super Saiyan form. After exchanging blows with Full Power Super Saiyan Goku, Perfect Cell overpowered and punched the Saiyan down into a cliff. Perfect Cell charged after him, but Full Power Super Saiyan Goku emerged from the rubble and attacked Perfect Cell with a powerful barrage of energy blasts. Unable to withstand Full Power Super Saiyan Goku's assault, Perfect Cell activated his Perfect Barrier, blocking Full Power Super Saiyan Goku's energy attacks and leaving them both exhausted.
Perfect Barrier is named in the Budokai Tenkaichi video game series and is Perfect Cell's Ultimate Blast. In Dragon Ball Z: Budokai Tenkaichi and Dragon Ball Z: Budokai Tenkaichi 2, its color was originally green. This was later fixed in Dragon Ball Z: Budokai Tenkaichi 3.
Budokai series and Burst Limit
It is named Energy Field in the Budokai video game series. It functions similarly to the barrier used by Artificial Human No. 17 and Artificial Human No. 18, however, it is slightly larger. Its color remains green from the previous Budokai games. Cell can also use it in his Semi-Perfect form in Dragon Ball Z: Burst Limit. It also has distinction of being the largest energy barrier in the video game since it covers half the screen when used in his Perfect form.