Can a computer screen cause ocular migrane?

Yes: Yes, but so can many other non-visual stimuli. Migraines are thought to be due to altered blood flow in blood vessels in the brain. Exactly what causes the altered flow and what symptoms arise because of it are often unique to an individual. So for you the computer screen may be the trigger--for someone else it might be sunlight, or exercise, or certain foods.

Yes: Ocular migraines are a particular subset of migraines so if you're prone to getting them then almost anything case cause them.

Migraine events occur due to neurotransmitter sensitivity to "triggers" of many causes, and computer screen blue light is one of many. This may respond to blue light blocker eye glasses, but preventative migraine meds may also work well. See a neurologist and evaluate various preventive approaches.