Comparative Study of the Topcon Tonometers CT-800 and TRK-2P and the Haag-Streit Goldmann Manual Tonometer and Topcon SP-1P

Inclusion Criteria: 1. be at least 18 years of age of either sex and any race or ethnicity; 2. be willing and able to provide written informed consent prior to any study procedures being performed; 3. be willing and able to follow all instructions and attend all study visits; Exclusion Criteria: 1. have only one functional eye; 2. have poor or eccentric fixation in either eye; 3. have corneal scarring or have had corneal surgery, including corneal laser surgery in either eye; 4. have microphthalmos in either eye; 5. have buphthalmos in either eye; 6. be a 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; 7. have dry eyes, meaning having been diagnosed by a physician with dry eyes and currently using a prescribed medication or daily use of an artificial tear; 8. be a lid squeezer - blepharospasm; 9. have nystagmus in either eye; 10. have keratoconus in either eye; 11. have any other corneal or conjunctival pathology or infection in either eye; 12. have a 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.