Noblex aspherilux midi LED Instrucciones Para El Uso página 17

at possibly low temperatures. Besides, it should be recharged once every
twelve months at least.
Brightness Control
A special feature of the circuit enables the brightness to be kept at a widely
high level even if battery voltage decreases considerably. To this effect, a
down controller is implemented in the circuit. Even if the batteries are ap-
proaching the final discharge voltage and, thus, the end of operation, there
will be no decrease in brightness. Therefore, a warning will be released
when the end comes near or when a warning has already been given and no
recharging done yet.
In terms of circuit technology, this down controller is especially adapted to
this case of application and features both a degree of efficiency and linearity
of the characteristic curve that have not been achieved by means of commer-
cially available DC/DC converters so far.
Aspheric Lens System
The lens system consists of three single lenses being arranged such that an
optimum focussing is reached from the very outset. Hence, no adjustment
option is provided for. The use of aspheres offers great advantages in the
correction of image distortions. The aspheric lens surface, as opposed to a
spherical one, has no spherical shape but is formed by a more complicated
surface shape such as a paraboloid, an ellipsoid or a rotationally sym-
metrical free-form surface the contour of which is described by technical
parameters precisely. As a result, improved possibilities for the design of an
efficient illumination system are opening up.
Working range
Because there is no common definition of the luminous range we prefer the
specification of a working range of portable light sources. This is done by the
following criteria:
•
Shortest working distance: The spot has a diameter of 25 cm and covers
half a sheet of paper in letter format.
• Longest working distance: The spot has over the whole area a bright-
ness of at least 0,25 lux and exceed therewith the illumination of the full
moon.
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