Final answer:
The property that an ophthalmic drug or its vehicle should possess in order to maximize drug penetration through the cornea is lipid solubility.
Step-by-step explanation:
The property that an ophthalmic drug or its vehicle should possess in order to maximize drug penetration through the cornea is lipid solubility. Lipid-soluble materials, which are nonpolar, can pass through plasma membranes more easily than polar materials, allowing for faster diffusion. Therefore, a drug or its vehicle with high lipid solubility can more effectively penetrate the cornea and reach its target site.