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MicroCloud Hologram Develops Multiple Algorithms for CGH Technology to Generate 3D Holographic Digital Content

MicroCloud Hologram Inc., a Hologram Digital Twins Technology provider, announced that it develops multiple algorithms for generating 3D holographic digital content based on computer imaging technology. These algorithms result from the Company’s independent research and development, which are conducive to further improving the Company’s intellectual property protection system, maintaining its technological leadership, and enhancing its core competitiveness.

According to the various technical issues faced by the current CGH technology, especially efficiency, HOLO develops and applies multiple algorithms in CGH technology and optimizes them to improve the efficiency and quality of 3D holographic digital images. CGH technology decomposes 3D objects into multiple basic units, then edits them with depth-of-field data and synthetically superimposes all basic unit data to obtain holographic digital images. Therefore, the vast computation involved in CGH is a great challenge for realizing real-time dynamic holographic 3D displays, especially in the case of complex 3D objects and large sizes of holographic digital images. HOLO applies three algorithms, namely dot matrix-based algorithm, polygon-based algorithm, and layered-based algorithm, to improve the computational efficiency and apply the optimized algorithm to CGH.

The CGH technology developed by HOLO based on the dot matrix-based algorithm represents 3D holographic objects by millions of dot matrixes, where each pixel of the object is represented by a dot that irradiates the spherical wave of the holographic digital content. The complex amplitude distribution of the holographic digital content can be obtained by superimposing all the target points. The computational burden can be significantly reduced by calculating the points of all possible objects in advance and storing them in the computer’s advance judgment. HOLO’s dot matrix-based algorithm can be optimized online and offline, and the 3D holographic digital dot matrix data can be pre-computed and stored in tables offline, thus speeding up the generation of holograms.

In addition, to reduce the internal memory occupation of 3D holographic digital content, the dot matrix-based algorithm can divide the 3D holographic objects into multiple 2D slice planes along the axial direction. And the center object point of each slice plane is dominant, the other target points’ can be calculated according to the relative position relationship in spatial coordinates by computing dot matrix shift in the same plane, and the result is obtained by adding the offset of all target points multiplying the corresponding amplitude. This enables a significant reduction in both computation and memory usage. HOLO’s dot matrix-based algorithm for CGH not only preserves the complete phase and depth of field data of the holographic digital image but also improves the overall computational efficiency.

Another way to speed up the computation in HOLO’s dot matrix-based algorithm for CGH is to reduce the computation area of each object point. For example, when high-precision holographic digital image content with millions of points of data is not required or when high-precision is not required for certain areas of the same layer or frame, polygon-based holographic digital content algorithms can be adopted. HOLO’s polygon-based algorithm treats 3D holographic objects as thousands of polygons instead of millions of points. In this way, the number of computational units is significantly reduced. The algorithm treats each polygon as a polygon aperture, and CGH is created by adding diffraction maps of all polygon apertures. In addition, combined with computer graphics rendering algorithms, the polygon-based algorithm can easily add textures and shadows to 3D scenes. The core problem of the polygon-based algorithm is the diffraction calculation between the tilted plane and the holographic plane. In the algorithm, 3D holographic objects are divided into thousands of tilted polygons that are not parallel to the planar layers. The polygon-based algorithm defines the base polygons with amplitude and phase functions in the local coordinate system and calculates their spectra, then computes the core parameters in the 3D transformation matrix from the vertex vectors of the base and tilted polygons using a matrix. The 3D holographic transform contains translation, rotation, and scaling transformations in 3D space, so the core parameters in the 3D transformation matrix can be used to calculate the CGH, thus saving polygon depiction, reducing diffusion calculations, and having no depth limitations. A polygon-based fully resolved algorithm is applied to speed up the computation, which can explicitly represent the resolved spectrum from the base polygon; the global angular spectrum of any polygon in the holographic plane can be computed using the resolved spectrum of the transformation matrix of the base polygon and the tilted polygon.

The dot matrix-based and polygon-based algorithms can provide accurate geometric information of 3D scenes, but they are still computationally intensive. HOLO also develops layered-based algorithms to reduce the number of computational units and speed up the computation. The layered-based algorithm divides the 3D holographic object into several layers parallel to the holographic plane, and each layer is considered a separate computational unit. The algorithm uses diffraction to calculate the sub-holograms of each layer and then obtains the CGH by superimposing all the sub-holograms. Because of the limited resolution of human eyes, the layered-based algorithm has smaller computational units than the dot-based or polygon-based algorithm. HOLO’s CGH technology also uses the angular spectrum method, which avoids the near-axis approximation, calculates the exact diffraction field, and optimizes computational speed.

HOLO’s dot-based algorithm, polygon-based algorithm, and layered-based algorithm can be applied to different 3D holographic digital content or the same 3D holographic digital content production according to the varying needs of customers and scenes. These three algorithms are designed to optimize the calculation method and improve the efficiency of the calculation, which can quickly generate holographic digital content. They have a very positive contribution in real estate, e-commerce, education, and other industries that are making content towards 3D holographic today. Various industries need 3D holographic content or lightweight product display services to speed up the terminal’s response efficiency. The 3D holographic digital content algorithm developed by HOLO can effectively improve computational efficiency, so it has fundamental industry significance and application value.