منابع مشابه
A programmable Fresnel transform pulse shaper.
We demonstrate the first reprogrammable Fresnel transform pulse shaper based on a modified direct space-to-time pulse shaping apparatus. In our approach, the pulse shaping lens and mask are implemented by a dual-layer liquid crystal spatial light modulator. The input mask subsequently undergoes a free-space Fresnel transform which causes quadratic dispersion of the output temporal waveform. Whe...
متن کاملDiscrete Fresnel Transform and Its Circular Convolution
Abstract—Discrete trigonometric transformations, such as the discrete Fourier and cosine/sine transforms, are important in a variety of applications due to their useful properties. For example, one well-known property is the convolution theorem for Fourier transform. In this letter, we derive a discrete Fresnel transform (DFnT) from the infinitely periodic optical gratings, as a linear trigon...
متن کاملOptical Image Encryption Based on Joint Fresnel Transform Correlator
Optical verification systems can make image hide in high-security phase key through the phase retrieval operation Conventionally, optical verification systems based on the joint transform correlator usually use Fourier transform. In this paper we propose the joint Fresnel transform architecture and use the methods of the projection onto constraint set and nonlinear transform to determine the p...
متن کاملFresnel diffraction effects in Fourier-transform arrayed waveguide grating spectrometer.
We present an analysis of Fourier-transform arrayed waveguide gratings in the Fresnel diffraction regime. We report a distinct spatial modulation of the interference pattern referred to as the Moiré-Talbot effect. The effect and its influence in a FT AWG device is explained by deriving an original analytical expression for the modulated field, and is also confirmed by numerical simulations usin...
متن کاملFourier Transform Spectroscopy
T he difficulties that always plague an experimental spectroscopist are those associated with resolving power, light-gathering ability, and wavelength and photometric accuracy. He sees a spectrum, such as that of atmospheric water vapor shown in Fig. 1, and deduces from it information about the atoms or molecules which gave rise to it. Such spectrograms can be taken at wavelengths from the far ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Physics Letters
سال: 1965
ISSN: 0031-9163
DOI: 10.1016/0031-9163(65)90580-9