We present a high dense views auto-stereoscopic three-dimensional display method with the projectors array and lenticular lens array(LLA) screen. The principle and configuration are demonstrated. This display method utilizes lenticular screen to modulate the information of projectors. To increase the dense of views, we propose a novel arrangement way of projectors array. In the experiment, the viewer can obtain smooth motion parallax and evident stereo feeling at optimal distance. Through analyzing and observation, the maximum display depth is found to be more than 50 cm.
The resolution of the parallax image is inversely proportional to the view number in the horizontal direction for the traditional autostereoscopic display based on a parallax barrier. To balance the resolution in the vertical and horizontal directions, two parallax interleaved barriers are designed. The liquid crystal display panel provides the synthetic image with square pixel units, and the pixels in a unit are distributed to different horizontal views. Two parallax interleaved barriers work together to modulate pixels in vertical and horizontal directions. 3D display with uniform resolution and low crosstalk is demonstrated.
To evaluate the light field display system with a liquid crystal display(LCD) and a holographic functional screen(HFS),the voxel theory based on the ray tracing is used.By analyzing the voxels defined by the cases of corresponding pixels overlapping completely and partially in the image space,the resolution characteristics of the system are discussed.The theoretical model is verified in the reconstruction experiment of a resolution target and compared with the calculation result of the presented system.Finally,we give an optimization method for the display image quality.
Reconstruction the computer generated Fresnel hologram of complex 3D object based on compressive sensing(CS) is presented. The hologram is synthesized from a color image and the depth map of the 3D object. With the depth map, the intensity of the color image can be divided into multiple slices, which satisfy the condition of the sparsity of CS. Thus, the hologram can be reconstructed at different distances with corresponding scene focused using the CS method. The quality of the recovered images can be greatly improved compared with that from the back-propagation method. What's more, with the sub-sampled hologram, the image can be ideally reconstructed by the CS method, which can reduce the data-rate for transmission or storage.
An integrated method based on optical and digital image processing is presented to suppress speckle in digital holography.A spatial light modulator is adopted to introduce random phases to the illuminating beam.Multiple holograms are reconstructed and superimposed,and the intensity is averaged to smooth the noise.The adaptive algorithm based on the nonlocal means is designed to further suppress the speckle.The presented method is compared with other methods.The experimental results show that speckle reduction is improved,and the proposed method is effective and feasible.
