Comparative Study of Non-contact Tonometers for Intraocular Pressure and Corneal Cell Thickness Measurements

Inclusion Criteria: * At least 18 years of age of either sex and any race or ethnicity; * Willing and able to provide written informed consent prior to any study procedures being performed; * Willing and able to follow all instructions and attend all study visits; * Best Spectacle Corrected Visual Acuity (BSCVA) of 0.3 logMAR (20/40 Snellen equivalent) or better in both eyes as measured using an ETDRS chart. Exclusion Criteria: * Only one functional eye; * Poor or eccentric fixation; * Corneal scarring or have had corneal surgery, including corneal laser surgery; * Microphthalmos; * Buphthalmos; * Contact lens wearer, meaning having worn soft contact lenses within the past 3 months and/or rigid permeable gas lenses within the past 6 months; * Dry eyes, meaning having been diagnoses by a physician with dry eyes and currently using a prescribed medication; * Lid squeezer - blepharospasm; * Nystagmus; * Keratoconus; * Any other corneal or conjunctival pathology or infection; * Condition or a situation, which in the Investigator's opinion, may put the subject at increased risk, confound study data, or interfere significantly with the subject's study participation.