Calibration
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12
SBOU155B – October 2015 – Revised February 2017
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OPT8241 Evaluation Module
5
Calibration
The CDK is factory-calibrated. The calibration on the CDK is for demonstration purposes only and is not
meant to be treated as the most accurate calibration possible. Since the CDK can be configured
dynamically using the software, the CDK goes out of calibration whenever a critical parameter is changed.
Three default profiles are provided in the hardware to serve as templates.
Table 6
lists the default
calibration profiles.
(1)
Since Long range profile derives from lens calibration profile, lens calibration is not redone in long range profile.
(2)
Profiles that have a parent derive all the calibrations from the parent. Calibrations in a child override the calibrations derived from
the parent.
Table 6. Calibration Profiles
Parameter
Long Range
Short Range
High Ambient
Parent Profile
Lens Only
Long Range
Long Range
Frame rate (fps)
30
60
30
Sub-Frames
4
2
4
Quads
6
6
6
Integration Duty Cycle (%)
30
10
5
De-aliasing
Enabled
Enabled
Enabled
Illumination Power (%)
100
40
100
Unambiguous Range (m)
10
5
5
Base Frequency (MHz)
60
60
60
De-aliasing Frequency (MHz)
40
40
40
Usable Range
4 m
1.5 m
1.5 m
Calibrations performed
Temperature, Common
phase offset, Pixel to
Pixel, Pixel cross-talk
(1)
Common phase
offset
(2)
Common phase
offset
(2)
Calibration is very sensitive to system parameter changes. Any change in a parameter value could put the
CDK in a non-calibrated state. The most common parameter changes that mandate re-calibration are
listed in
Table 7
.
Table 7. Calibration Sensitivity Table
Parameter Changed
Re-Calibration Required?
Common phase offset
Pixel-to-Pixel
Differences
Non-Linearity Calibration,
Pixel Cross-Talk
Calibration
Unambiguous range (any change in
modulation frequency)
Yes
Yes
Yes
Frame rate, number of quads,
number of sub-frames (any change
in quad timing)
Yes, but to a small extent
No
No
Integration duty cycle
Yes, but to a small extent
No
No
Illumination power
Yes
No
No
