Note: Intensity control of a phase-shift based laser scanner for reducing distance errors caused by varying surface...

Area of Science:

• Optics
• Metrology
• Signal Processing

Background:

• Phase-shift measurement methods determine distance using the phase difference between reference and measured light signals.
• Variations in object color cause significant changes in measured signal intensity, even at constant distances.
• This intensity variation leads to phase delay errors due to wide dynamic range inputs in signal processing circuits.

Purpose of the Study:

• To propose and evaluate an intensity control method for phase-shift distance measurement.
• To mitigate phase delay errors caused by signal intensity fluctuations.
• To enhance the accuracy of distance measurements for objects with different colors.

Main Methods:

• Development of a novel intensity control algorithm for optical measurement systems.
• Integration of the control method into a standard phase-shift measurement setup.
• Experimental validation using targets with varying spectral reflectivity.

Main Results:

• The proposed intensity control method effectively stabilizes the measured signal intensity.
• Significant reduction in phase delay errors was observed across different object colors.
• Improved distance measurement accuracy was demonstrated compared to conventional methods.

Conclusions:

• The intensity control method is a viable solution for overcoming signal intensity variations in phase-shift measurements.
• This approach enhances the robustness and accuracy of optical distance sensing, particularly for diverse target surfaces.
• The findings have implications for applications requiring precise distance determination in dynamic or variable lighting conditions.