Acuity AP820 Laser Scanners
Rev. 3.3
29
9.
Description of the control commands
9.1
Exposure control
This register is for the manual control of the sensor's exposure. It only has an effect
when the register exposure control mode is set to 1 for manual.
Register
Bit No.
Meaning
Reg.1
6 to 0
value Bit 6 to 0
0x000 = maximum exposure time
and brightness.
0x3FF = minimum exposure time
and brightness.
Reg.2
2 to 0
value Bit 9 to 7
9.2
Calculation of the Exposure Time
The sensor works with 200 half images per second. This is a 5.0 msec period.
The maximum exposure time is 1.0 msec. The exposure time can be keyed in 1024
steps.
Based on this, the minimum exposure time can be calculated as:
maximum exposure time/1024=1 µsec
To identify from which position on the exposure was carried out, it is required that a
position encoder is plugged to the scanner. The position will be saved at the end of an
image.
5.0
msec period
9.3 Limiting the Range Z
- Exposure time -
Store
Position
encoder data
The registers for limiting the range Z define the area in which the sensor is being read
out. A profile cannot be generated outside of a defined window.
With this function, it is possible to put a measurement “window” in front of the sensor, in
order to reduce the Z-measurement range at the front and back.
9.4
Amplification
The amplification of the sensor signal can be influenced. In cases of very dark and
reflecting surfaces, the value can be increased here.
Register
Bit No.
Meaning
Reg.1
6 to 0
value Bit 6 to 0
0x000 = minimum amplification.
0x3FF = maximum amplification.
Reg.2
2 to 0
value Bit 9 to 7
