Currently the diode laser is widely used in the field of optoelectronics, especially in precise measurement based on laser-interferometry. Laser wavelength stability is a property that critical to the measurement. Since the laser wavelength is easy to be influenced by the environment and drive current, real-time monitoring and calibration of diode laser wavelength is extraordinary important for interferometry. In this paper, a real-time wavelength monitoring and calibration system for diode laser based interference measurement were developed. The experiment system was built and conducted to verify the feasibility of the system.
In this paper, a structural illumination based technology for microscopic surface topography measurement is investigated, in which only one shot structural illumination image is grabbed and a more efficient optical sectioned image reconstruction algorithm based on Hilbert transform was proposed. Compared with other methods, the technology can avoid strip artefacts problems of in-focus images resulting from the sinusoidal phases mismatch in spatial domain in conventional three-step phase-shifting since the phase-shifting steps decreases from three to one, and the measurement time is decreased effectively. The experimental testing is carried out to verify the feasibility and its measurement accuracy.