Soft lenses are the most common type of lens and are what you normally relate to when you talk about lenses. A soft lens has a predetermined length of life, from one day to a year. The soft lens is almost always instantly comfortable but a rigid lens takes some getting use to, from a couple of days up to a month. After the breaking in time the rigid lens will also be comfortable. A rigid lens doesn�t have any predetermined length of life. Instead it's the condition of the lens that determines when it's time to change the lens.