Final answer:
An Oil droplet cataract typically presents as a round, translucent irregularity that scatters light, causing diffused vision. During an eye surgery involving lasers, parallel light rays are required to focus energy accurately for repairing a tear in the retina.
Step-by-step explanation:
The characteristic appearance of an Oil droplet cataract is a round, translucent irregularity. This particular type of cataract allows some amount of light to pass through but scatters it, leading to diffused vision. In a relaxed normal-vision eye, during procedures like spot-welding the retina to repair a tear, the laser light entering the eye must be parallel to ensure that the energy is precisely focused on the intended area without causing damage to the surrounding tissues.