TRK-3 Conformance to Standards for Tonometers

Inclusion Criteria: 1. Age at least 22 years at the time of the informed consent 2. Provide voluntary written consent for participation in the study Exclusion Criteria: 1. Have only one functional eye 2. Have difficulty in ocular fixation or eccentric fixation in either eye 3. Have corneal scar or have a history of corneal surgery such as corneal laser surgery (cataract surgery is acceptable) 4. Have microphthalmia 5. Have buphthalmos 6. Wear contact lens (have used soft contact lenses within the last 3 months and/or hard contact lenses within the last 6 months) 7. Have dry eyes and taking prescription medication or using artificial tears daily 8. Have blepharospasm 9. Have nystagmus 10. Have keratoconus 11. Have corneal or conjunctival lesions or infections 12. Have a central corneal thickness of \<500μm or \>600μm 13. Have corneal astigmatism \>3D 14. Have known allergy to ophthalmic anesthetics 15. Have known allergy to sodium fluorescein