Delefilcon A contact lenses with different base curves and diameters worn in Period 1, followed by delefilcon A contact lenses with standard base curves and diameters worn in Period 2. During each period, the contact lenses will be worn bilaterally (in both eyes) for 6 (+2) hours. A one-to-two day washout will separate the wear periods.

Delefilcon A contact lenses with standard base curves and diameters worn in Period 1, followed by delefilcon A contact lenses with different base curves and diameters worn in Period 2. During each period, the contact lenses will be worn bilaterally (in both eyes) for 6 (+2) hours. A one-to-two day washout will separate the wear periods.

Silicone hydrogel contact lenses for the optical correction of refractive ametropia (myopia and hyperopia) in phakic or aphakic persons with non-diseased eyes with up to approximately 1.50 diopters (D) of astigmatism that does not interfere with visual acuity.

Lens movement (overall lens fit) will be evaluated by the investigator using a slit lamp with the eye in primary position. Lens movement (overall lens fit) will be graded on a 5-point scale as follows: -2 = unacceptably tight (reduced movement, unacceptable); -1 = Acceptably tight (reduced movement, acceptable); 0 = Optimal fit / movement; +1 = Acceptably loose (excessive movement, acceptable); +2 = Unacceptably loose (excessive movement, unacceptable).

Lens movement (overall lens fit) will be evaluated by the investigator using a slit lamp with the eye in upward gaze, downward gaze, looking to the left, and looking to the right. Lens movement (overall lens fit) for each gaze will be graded on a 5-point scale as follows: -2 = unacceptably tight (reduced movement, unacceptable); -1 = Acceptably tight (reduced movement, acceptable); 0 = Optimal fit / movement; +1 = Acceptably loose (excessive movement, acceptable); +2 = Unacceptably loose (excessive movement, unacceptable).

Lens position (centration) will be evaluated by the investigator using a slit lamp with the eye in primary position. Lens position (centration) will be graded on a 3-point scale as follows: 0 = Optimal centration; 1 = Acceptable centration; 2 = Unacceptable decentration.