Instruction Manual Easygraph
Page 7
4
Description of the Unit and its Functions
The OCULUS Easygraph belongs to the most
modern generation of precision topographic
measuring instruments. It combines keratometric and
topographic measuring methods in a single unit.
Measurement of the corneal surface is carried out
through a system of rings which are reflected at the
cornea. The resulting data are evaluated by the
computer.
Technical Principle:
A illumination system with a special reflector
illuminates a transparent calotte or "skullcap" with
concentric circles from behind.
The image of this "cap" is reflected from the
examinee's eye, which is opposite to it.
This virtual image is captured by a precision lens and
a tandem-arranged CCD camera.
All distortions found in the radii of curvature of the
examinee's eye thus become available for use by the
measuring process.
The image is then processed by the measuring unit
for evaluation, i.e. it is made available to the PC in
digitized and compressed form for further
processing.
After receiving appropriate data from a screen
diagram, the PC uses this information to develop a
topographic image of the cornea.
It then shows the measurement results on the screen
not only in color but also in the form of a diagram
and a 3-dimensional image.
5
Appropriate Use / Intended Application
The OCULUS Easygraph is a measuring instrument
which is intended for eye examinations and only for
the uses described in this Instruction Manual.
The unit is used for measuring corneal topography
and has been designed for use in fitting contact
lenses.
It may therefore be used only by persons who have
been instructed in its use and whose professional
training, knowledge, and practical experience ensure
that they will work with the unit appropriately.
The OCULUS Easygraph has been designed for use
in the examination rooms of practicing
ophthalmologists, for hospital departments, opticians
and optometrists. It may be used only at locations
specifically designated for it or when attached to an
examination unit.
The OCULUS Easygraph may be used only with
original parts and accessories delivered by us and in
a technically flawless condition.
Electric power must be supplied by the special power
pack (cf. the electrical equipment specifications).
Other types of connection are not permissible.
Please also observe the safety precautions described
above!
6 Start-up
6.1
Directions for Transport and Storage
Should you transport the unit to another location,
please do so very carefully.
Avoid the vicinity of heating units and humidity both
during use of the instrument and when it is stored.
Check the unit for damage after each relocation.
Under no circumstances should you put a damaged
unit into operation; rather, please get in contact with
our service department.
The optic components in the unit may become
covered by condensation if you store the unit in a
cold room or in a vehicle during the cold part of the
year or if there are wide changes from cold to warm
in the ambient temperature.
Please give the unit time to acclimatize to its new
surroundings before using it for the first time.
The conditions set by IEC-Norm No. 601-1 for
transport and storage are:
Ambient temperature: -40°C to +70°C
Relative Humidity:
10 % to 100%
including
condensation
Air pressure:
500 hPa...1060hPa
(7.3 psi...15.3 psi)
These levels apply for a period of 15 weeks at most
if the unit is kept in an appropriate case.