OPTIKON BIOLINE, Инструкция по установке и эксплуатации, Страница: 13 / 42

BIOLINE Manual for installation and use
OPTIKON 2000
5 GENERAL INFORMATION
The piezoelectric effect in natural crystals was observed for the first time by Pierre
and Jacques Curie in 1880. They showed that certain types of crystals (quarz,
tourmaline), when deformed by mechanical causes, generate an internal electric
field. Vice versa when an electric field is applied to these crystals, mechanical
distortion of the material occurs. Some ceramics, treated in an appropriate way using
a polarisation process, acquire the piezoelectric properties of natural crystals. These
ceramics, obtained using up-to-date technology, are defined as piezoelectric. The
BIOLINE probe contains a piezoelectric ceramic which, when stressed with an
electrical impulse
“
vibrates” at the frequency of 10 megahertz (10 million oscillations
per second). This movement of the ceramic transductor generates an extremely low
energy ultrasound wave which crosses the cornea, aqueous humor and any other
objects or tissues found along the signal propagation pathway. The ultrasound wave
partly crosses the obstacles and is partly reflected by the latter towards the source
(namely the actual transductor). It takes this reflected energy a certain amount of
time to turn towards the transductor and this time is proportional to the distance from
the obstacle. The measurement of this time and the experimental knowledge of the
speed of the echo, allow the distance from the object (the retina for example) from
the emitter (probe tip) to be mathematically calculated. The characteristics of the
return echo are then processed by a fast microprocessor which detects its reliability
for measuring purposes (automatic acquisition).
5.1 SYSTEM DESCRIPTION
The portable BIOLINE - OPTIKON 2000 Biometer – is a portable microprocessor-
based instrument for measuring the axial length of the eye and for calculating the
intraocular lens appropriate for restoring emmetropia, after removing the cataract.
Reliability, versatility, accuracy and simplicity, together with an attractive and
functional design, make this a unique instrument among the various models available
on the world market.
The principal functions are activated by a few dedicated keys. All the other
parameters can be changed by using the four lateral arrows. Presentation of the
echo in real time allows the operator to line up the probe easily even in the most
difficult cases. In order to carry out the measurements more easily it is possible to
select signalling with voice synthesis of standard deviation, in addition to traditional
signalling with acoustic tones. Finally the internal thermal printer provides an
accurate recording of the measurements taken as well as the parameters relating to
the selection of the intraocular lens.
Code 141002EN 5-1 26.10.05 Rev.0