Optical system design of direct detection short-pulsed laser proximity sensor

Date

2017

Author

Korkmaz, Emrah

Metadata

Show full item record

Item Usage Stats

10
views

4
downloads

In this study, we designed a Laser Proximity Sensor system that measures the distance by analyzing the echo signal reflected from object using time-of-flight principle. The sensor makes a direct-detection using a short-pulsed laser and is capable of detecting objects and measuring distances in a range between 0.5 m and 10 m far from the system. Reflectivities of objects are assumed to lie between 20% and 90% and obeying to Lambertian BSDF (Bi-Directional Scatter Distribution Function). A mathematical model for the laser propagation in the atmosphere was developed. Receiver and transmitter optical system design were performed using a ray tracing software (Zemax). Laser central wavelength was measured for the temperature region of interest (i.e. 0 – 70 C). A bandpass optical filter was designed to block the background light having a wavelength ranging outside of the laser’s emission spectrum at its all operation temperatures. Various signal-processing algorithms were developed to extract the echo signal buried in noise. Finally, laser diode driver, high-speed receiver amplifier and time to digital converter circuit board were designed.

Subject Keywords

Lasers., PIN diodes., Photodiodes., Optical detectors.

URI

http://etd.lib.metu.edu.tr/upload/12621700/index.pdf
https://hdl.handle.net/11511/27038

Collections

Graduate School of Natural and Applied Sciences, Thesis