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Updated: Aug 9, 2025

Subsurface Defect Localization by Structured Heating Using Laser Projected Photothermal Thermography
Published on: May 15, 2017
Simple high-precision diode laser system with digital control
Abstract:
A simple wavelength tunable diode laser system has been designed and fabricated for laboratory use. Both the current and temperature controllers are based on an AVR microcontroller, and the experimental controls have been implemented with the help of daemon programs running in a message passing interface environment, which allows the users to run the control server and client programs on separate computers. The stability of the controllers has been tested using a distributed feedback (DFB) diode laser with a central wavelength of 852.3 nm. A noise spectral analysis of the current controller with and without the use of the diode laser as the active load has been demonstrated. The absorption spectra of 6S 1/2→6P 3/2 transition of 133 C s, as recorded by using the DFB laser system developed, are also presented.

