Development of an optical system calibration and alignment methodology using Shack-Hartmann wavefront sensor

Adil, Fatime Zehra
Shack-Hartmann wavefront sensors are commonly used in optical alignment, ophthalmology, astronomy, adaptive optics and commercial optical testing. Wavefront error measurement yields Zernike polynomials which provide useful data for alignment correction calculations. In this thesis a practical alignment method of a helmet visor is proposed based on the wavefront error measurements. The optical system is modeled in Zemax software in order to collect the Zernike polynomial data necessary to relate the error measurements to the positioning of the visor. An artificial neural network based computer program is designed and trained with the data obtained from Zernike simulation in Zemax software and then the program is able to find how to invert the misalignments in the system. The performance of this alignment correction method is compared with the optical test setup measurements.


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High precision is the dominant advantage that resonant sensors have over other types of analog sensors (sensors with a subsequent analog-to-digital converter). The resolution of these precise sensors is determined by both frequency resolution and sensitivity of the sensor. The sensitivity is highly related to the sensitivity of the MEMS resonator. However, the frequency resolution is dominantly defined by the closed-loop circuitry if noise contribution of the resonator is assumed to be smaller than that of ...
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This thesis work covers the numerical analysis and design of infrared photon detectors with a focus of HgCdTe based devices. An in-house numerical tool is utilized for the design and characterization process, where the Poisson, current and continuity equations are solved numerically with the high precision in electrical and optical properties. A high operating temperature alternative substrate mid-wave HgCdTe detector is designed benefiting from the generation-recombination dark current suppression. The adv...
Citation Formats
F. Z. Adil, “Development of an optical system calibration and alignment methodology using Shack-Hartmann wavefront sensor,” M.S. - Master of Science, Middle East Technical University, 2013.