A deep neural network with differential architecture is proposed to reconstruct turbulence phases from single-shot intensity images of extended targets, and a phase spatial modulator (SLM) is used for wavefront correction. The neural network takes the inputs of an aberrated intensity image and a background image and separates the turbulence phase from the target structure by comparing the high-dimensional features of the two inputs. The SLM is used to simulate atmospheric turbulence in the optical path and for correction of the external turbulent field. This method is verified in the optical path with the flame field.
Diffractive optical element (DOE) has special dispersion and temperature characteristics, which makes them widely used in optical systems that require both athermalization and achromatic aberrations correction. The multi-layer DOE (MLDOE) can improve the diffraction efficiency overall the broad waveband, but its diffraction efficiency decreases with ambient temperature changing. When the ambient temperature changes, the micro-structure heights and the refractive index of the substrate materials of MLDOE change, ultimately affecting the optical transform function (OTF). In this paper, the influence of ambient temperature on the diffraction efficiency of MLDOE is proposed and its relationship is derived, a computational imaging method that combines optical design and image restoration is proposed. Finally, a mid-infrared waveband infrared optical system with athermalization and achromatic aberrations corrected based on this method is designed. Results show that this method can effectively improve the imaging quality of refractive-diffractive hybrid optical systems.
In this dissertation, the mathematical model of effect of manufacturing errors including microstructure relative height error and relative width error on diffraction efficiency for the harmonic diffractive optical elements (HDEs) is set up. According to the expression of the phase delay and diffraction efficiency of the HDEs, the expression of diffraction efficiency of refraction and diffractive optical element with the microstructure height and periodic width errors in fabrication process is presented in this paper. Furthermore, the effect of manufacturing errors on diffraction efficiency for the harmonic diffractive optical elements is studied, and diffraction efficiency change is analyzed as the relative microstructure height-error in the same and in the opposite sign as well as relative width-error in the same and in the opposite sign. Example including infrared wavelength with materials GE has been discussed in this paper. Two kinds of manufacturing errors applied in 3.7~4.3um middle infrared and 8.7-11.5um far infrared optical system which results in diffraction efficiency and PIDE of HDEs are studied. The analysis results can be used for manufacturing error control in micro-structure height and periodic width. Results can be used for HDEs processing.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.