Holographic display with optical computational Fresnel convolution to broaden distance

Abstract

As a method of near-field diffraction in the condition of the paraxial approximation, the Fresnel convolution (FR-CV) method is widely used in hologram generation and other applications. However, it is applicable to near-field diffraction, and the quality of holographic reconstruction degrades seriously with the increase of diffraction distance. Moreover, its hologram generation speed is limited due to the use of three fast Fourier transforms in the convolution operation. Nevertheless, there are also many application scenarios that need longer distance diffraction. To achieve a holographic display in broadened distance with high generation speed and reconstruction quality, an optical computational Fresnel convolution method is proposed in this paper. Since an optical Fourier lens is used to perform optical calculations for Fourier transforms in our proposed method, the hologram generation speed of the proposed method is approximately 8 times faster than that of the FR-CV method. Moreover, the reconstructed image with our proposed method can be successfully and clearly displayed at both short and longer diffraction distance by changing focal lengths of the Fourier lens. The effectiveness and superiority of the proposed method have been validated by both numerical simulations and optical experiments.

Optimized Iterative Algorithm to Generate Computer-Generated Holograms Based on the Intermediate Angular-Spectrum Method

“…It is obvious that proposed method spends less time generating optimized POHs under the same number of iterations. In addition, proposed method could also be used in optical computational Fresnel convolution method [26], of which the computational complexity is 4N 2 log 2 N in each iteration, to suppress the speckle noise. Moreover, proposed method can achieve high-quality holographic 3D display when combined with layer-based method [21].…”

Multichiral Vortex Beam for High-Quality Information Encryption

“…Optical holography technology, utilizing computer-generated holograms to reconstruct optical fields, has achieved significant success in various application domains such as 3D display, 1−3 optical microscopy, 4−6 optical computation, 7,8 and 3D printing. 9,10 Optical holography technology also plays a huge role in the field of optical encryption.…”

“…Optical holography technology, utilizing computer-generated holograms to reconstruct optical fields, has achieved significant success in various application domains such as 3D display, − optical microscopy, − optical computation, , and 3D printing. , Optical holography technology also plays a huge role in the field of optical encryption. Traditional holographic techniques employ physical dimensions such as polarization, wavelength, and others as multiplexing channels, − yet these channels have limited availability and suffer from significant crosstalk.…”