There isn't a right or a wrong Passive Infrared
technology, there's just the option that suits a specific lighting situation.
The solution you choose all depends on what you want it to do.
PIR sensors
in theory
Infrared sensors receive heat radiated from the human body. Segment
lenses divide the detection zone into passive and active zones. This way, the
highly sensitive sensors can detect persons or warm objects moving between the
zones as a change in voltage. Even the smallest of movements are registered. The
quality is governed by resolution (number of detection zones), design and the
software.
PIR sensors
in practice
Movements at right angles to the sensor (tangential movement) can be
detected particularly well by passive infrared sensors. With radial movements,
reach is usually shortened because detecting a change in temperature in this walking
direction is more difficult. The point at which sensors are positioned should
ensure they are not disturbed or distracted by
PIR sensors
from STEINEL Professional
While developing our IR systems, we pay attention to precision and
reliability, we pay attention to precision and reliability. Technological
advances, such as multi-lens and multi-sensor technology, permit tremendous
accuracy in reach settings and detection spectrum. Working with an
exceptionally high number of switching zones, our IR Technology ensures sensors
ensure precision and reliability.
What are infrared rays?
Any object with a temperature that lies above
absolute zero (- 273° C), gives offelectromagnetic radiation. Heat radiation is
well suited as automatic remote control.
How does a PIR motion detector work?
The surrounding heat radiation
is grouped by a segment lens and guided to the pyro-detector.If a heat source
moves in the detection area, the heat radiation changes and thepyrosensor
releases a voltage. This voltage is assessed by the downstream electronics.
Benefits of
PIR
• Very good tangential detection
• Detection reach and angle of coverage can be set with precision
• High number of switching zones
• Also suitable for outdoors as only heat radiation is detected
• Twilight threshold and light 'ON' duration and detection zone can be set
to suit individual needs
• Electronic temperature compensation to avoid differences between winter
and summer detection quality outdoors
TODAY, LIGHT HAS BECOME A
KEY ISSUE.
A MODERN, ENVIRONMENTALLY FRIENDLY AND THEREFORE ENERGY SAVING LIGHT WITH
VARIOUS APPLICATIONS.
•
Light
for seeing - for optimum illumination
•
Light
to be seen - that creates highlights
•
Light
to see - as decorative element
•
Light
for saving - for energy-conscious illumination
•
Light
for safety - as deterrence
WITH THE STEINEL MOTION DETECTORS LIGHT CAN BE DIRECTLY TARGETED AND
CONSCIOUSLY UTILISED
The detectors automatically
switch the light depending on the respective environment brightness and
presence of persons. The passive infrared technology makes this possible, i.e.
built-in IR sensors record thermal radiation and convert the same to a
measurable electric signal. Bodies, such as the human body, emit thermal
radiation; such thermal radiation lies within the so-called infrared range and
is invisible to the human eye.
The heart of passive
infrared (PIR) sensor technology is the lens. As the “eyes” of the sensor, it
collects the infrared energy data generated by matter in space. Moving energy
sources, such as humans, will emit radiant heat that is then collected by the
lens. These data are passed to the sensor circuitry for interpretation; based
on this, a signal is transmitted to switch lighting in the area. Because
appropriate signals depend on the collection of comprehensive and accurate
data, the quality and design of the lens is critical.
Fresnel
Lens Technology
The lens technology most commonly used in passive infrared
occupancy sensors today is based on the Fresnel principle, which is that the
contour of the refracting surface of a lens defines its focusing properties. A
non-spherical surface contour (also referred to as “aspheric”) will minimize
optical aberrations and refract a higher percentage of the light energy being
collected in the desired direction. This aspheric surface consists of grooves
that can be varied in depth and thickness.
Advanced
Lens Technology
While Fresnel lens technology is the foundation for the lenses
used in The STEINEL PIR sensors, there are important differences between common
Fresnel lens and the advanced types found in our products. Most importantly,
Steinel utilizes lenses that have been specifically developed for use in our
sensors.
Structure of a Fresnel lens
Combination of single lenses,arranged in a circular segmentMaximum
horizontalangle of coverage of 180° with a Sneak-by protection:STEINEL Fresnel
lenses havea second optical window underthe main detection zone.
The radiation under the sensoris therefore also detected.
This involves an exclusive specification and lens design process,
during which a prototype lens is crafted by hand and tested for effectiveness.
Once the lens has passed this rigorous testing stage, the manufacturing process
can begin, utilizing advanced plastics materials to customize lenses with
excellent infrared optical properties. This process is applied for each sensor
product to ensure that the specific capabilities intended for each sensor type
are obtained.
Another significant difference between Steinel patented lenses and
common Fresnel lenses is the use of multiple lens segments and tiers. This
unique design is accomplished by identifying and selecting specific segments or
“cells” of a common Fresnel lens design that have exceptional optical
properties for a specific range. These cells are then pieced together with
other segments. The effect, rather like a patchwork quilt, is illustrated in
the [image below], which represents a lens surface. Lastly, these segments are arranged
in levels, or tiers, to achieve multi-dimensional coverage.
Experts in the field of optics have developed
different designs or patterns, each of which is protected by its own patent, to
provide different coverage capabilities.
OPERATION OF A MULTI LENS WITH 1, 2 OR 3 PYRO DETECTORS
