Answer : Using Opthalmic Sponges.
Explanation : Collecting tears with the trivial methods is often not possible as to avoid the tear reflex is a different problem. Tear collection with glass capillaries are the most widely used method for taking samples and is considered to be the best method for avoiding tear reflex.
To collect tears are from elderly people or small children's who had difficulties with glass capillaries; for them ophthalmic sponges was used.
This kind of opthalmic sponges proved to be well tolerated by the patient, especially in small children's, and also enabled standardization of the tear collection in terms of volume.