Retroreflective sensor beam size, Wiring diagrams – Banner PicoDot PD Series User Manual
Page 4

Retroreflective Sensor Beam Size
Unlike conventional retroreflective sensors, the
retroreflective laser has the ability to sense relatively small
profiles. The figures demonstrate the diameter of the
smallest opaque rod that reliably breaks the laser beam at
several sensor-to-object distances. These values assume an
excess gain of about 10×. Flooding effects are possible
when the gain is much higher (reduce sensor gain in this
situation in order to reliably detect minimum object sizes).
Note the shape of the beam is elliptical and its size
increases as the distance from the sensor increases.
Minimum object detection sizes are dependent on both the
object’s distance from the sensor, and the direction (with
respect to the beam’s X and Y axes) in which the object
crosses the beam.
LASER LIGHT
DO NOT STARE INTO BEAM
CLASS 2 LASER PRODUCT
Avoid exposure - laser light
emitted from this aperture
PEAK POWER 2 mW
20KHz 10% DUTY CYCLE
660 - 680 nm
COMPLIES TO 21 CFR PART
1040.10 AND EN60825-1:1994
Sensing Distance = X
Approx.
0.5 m rad = 0.029º
Approx. 2 mm
W = 2 mm + 2X(tan 0.029º) = 2 mm + X(0.001)
W
Laser Emitter
Figure 2. Beam divergence at 25ºC (beam size vs. distance)
LASER
LIGHT
DO NOT ST
ARE INT
O BEAM
CLASS 2 LASER
PRODUCT
Avoid exposure - laser light
emitted from this aperture
PEAK
POWER 2 mW
20KHz 10% DUTY
CYCLE
660 - 680 nm
COMPLIES T
O 21 CFR
PART
1040.10 AND EN60825-1:1994
Y
Beam divergence
approximately 1 milliradian
X
Beam size and shape
at aperture
Figure 3. Minimum object detection size vs. distance
Distance from
Sensor to Object
Minimum Detection size
X
Y
0.3 m (1 ft)
1.78 mm (0.07 in)
3.30 mm (0.13 in)
1.5 m (5 ft)
2.03 mm (0.08 in)
4.06 mm (0.16 in)
3 m (10 ft)
3.05 mm (0.12 in)
5.08 mm (0.20 in)
9 m (30 ft)
5.08 mm (0.20 in)
8.13 mm (0.32 in)
15 m (50 ft)
9.65 mm (0.38 in)
12.7 mm (0.50 in)
18 m (60 ft)
12.7 mm (0.50 in)
19.05 mm (0.75 in)
Installation Notes - Class 2 Laser Safety Notes
Low-power lasers are, by definition, incapable of causing eye injury within the duration
of a blink (aversion response) of 0.25 seconds. They also must emit only visible
wavelengths (400 to 700 nm). Therefore, an ocular hazard may exist only if individuals
overcome their natural aversion to bright light and stare directly into the laser beam.
•
Do not stare at the laser.
•
Do not point the laser at a person’s eye.
•
Mount open laser beam paths either above or below eye level, where practical.
•
Terminate the beam emitted by the laser product at the end of its useful path.
LASER LIGHT
DO NOT STARE INTO BEAM
CLASS 2 LASER PRODUCT
Avoid exposure - laser light
emitted from this aperture
PEAK POWER 2 mW
20KHz 10% DUTY CYCLE
660 - 680 nm
COMPLIES TO 21 CFR PART
1040.10 AND EN60825-1:1994
CAUTION: Use of controls adjustments or performance of procedures other than those specified herein
may result in hazardous radiation exposure; per EN 60825. Do not attempt to disassemble this sensor
for repair. A defective unit must be returned to the manufacturer.
Wiring Diagrams
Quick disconnect wiring is functionally the same.
PD49 Series Ruggedized PicoDot
®
4
www.bannerengineering.com - tel: 763-544-3164
P/N 67450 Rev. B