Examples where “vision” (optasia) denotes a physical and supernatural event abound. In the New Testament, it is more often physical than not, where the term (optasia) is used these five times in total:
Given that this vision (optasia) is a reference to Jesus's appearing, it is also, inevitably, a physical appearance since the author of Acts is clear in reporting that Paul said it was physical. He said in the immediate context that the light shone all around them and that “we had all fallen to the ground” (in verse 13). This is relevant because if Paul and the author of Acts are competent users of Greek, then we can expect that a physical appearance like this can be properly called an optasia.