An intraocular pressure (IOP) includes a transmission film component, which is in direct contact with intraocular aqueous humor and configured to sense pressure fluctuations in the intraocular aqueous humor; a reflective film component set on an inner side of the transmission film component; and an adhesion layer component set on an inner layer of the reflective film component and configured to connect to an attachment device. An enclosed space formed by the reflective film component and the transmission film component constitutes a resonance chamber, which is filled with a filling medium. When a pressure in the intraocular aqueous humor is changed, the transmission film component is deformed, resulting in a change in a near-infrared (NIR) spectrum reflected by the reflective film component; the TOP is detected according to the change of the NIR spectrum.