| 摘要 |
<p>The present invention relates to a miniature transducer which is particularly suitable for use in opthalmic measurements and more specifically in the measurement of intra-ocular pressure in vivo. To this end, the miniature pressure transducer of the present invention comprises a container having a concave surface for fitting on the eyeball of a patient and a central aperture is formed in the concave surface through which one end of a permeable core extends. A first coil is fixed to the other end of the core interiorly of the container and a second coil is fixed to the container between the concave surface and the first coil. Resilient means normally urges the first coil and core to a rest position whereat the first and second coils abut one another and the first end of the core projects through the aperture to be acted upon by pressure in the eyeball with which the transducer is associated. Thus, the core and the first coil are moved by pressure of the eyeball such that the resonant frequency of the coils is changed in a manner directly proportional to the intra-ocular pressure. In use, it is not necessary for any external connections to be made to the transducer and it is merely necessary to bring a device such as a grid dip oscillator into proximity with the transducer for coupling with the resonant frequency of the coils in the container. Accordingly, the device of the invention is exceptionally simple in construction and reliable in operation and does not require any external connections or fittings for use to make measurements of the intra-ocular pressure of the eyeball. On the other hand, devices of the prior art require external fittings with resultant problems to the wearer.</p> |
