PURPOSE: To precisely perform alignment in the visual line direction of an eye to be inspected and perform measurement in an appropriate operating distance state.

CONSTITUTION: The eye E to be inspected is irradiated with luminous flux from a light source 7 for measurement, and reflected light is converged on an alignment light receiving part 15 via an objective lens 4, etc. When a testee depresses a measurement start button 34, a motor 27 with gear is driven, and an objective unit 10 reciprocates by a specific moving stroke in the visual line direction of the eye E to be inspected, then, the optimum alignment position can be detected by the alignment light receiving part 15. A rotary solenoid 23 is driven at that position, and compressed air is sprayed on the cornea Ec of the eye E to be inspected from a nozzle 1, then, the cornea Ec is deformed. Such deformed state is detected by a deformation detection light receiving part 18, and the internal pressure of an air chamber 5 at that time is ready by a pressure sensor 36, then, it is converted to an intraocular tension value.