The invention provides a Fresnel lens, a camera light-filing device and a mobile terminal. The Fresnel lens comprises a first face and a second face opposite to the first face, wherein the first faceis a smooth surface, and the second face comprises a grain setting region and a grain non-setting region. By adopting the Fresnel lens with the second face provided with the grain setting region and the grain non-setting region, a problem that the quadrangle uniformity difference is large since the luminescence center of a light-filling lamp and a framing center of the camera is misaligned can becompensated after the Fresnel lens is subsequently applied to the camera light-filling device, therefore, the imaging effect of the shot image is perfected and the quality of the shot image is improved when the camera light-filling device is applied to the mobile terminal and the camera light-filling device is used for performing the front shooting.

Fresnel lens, camera light-filling device and mobile terminal

The invention provides a virtual reality display device, which comprises at least one display and at least one optical module. The display is adapted to provide an image light beam to a left or righteye of a user. The optical module is arranged on a transmission path of the image beam, and is positioned between the display and the left or right eye of the user. The optical module comprises a first Fresnel lens, wherein the first Fresnel lens comprises a plurality of annular structures surrounding an optical axis thereof, each of the annular structures has an effective refracting surface and anon-optical effective surface positioned between the optical axis and the effective refracting surface, and each effective refracting surface is connected with the corresponding non-optical effectivesurface. An average inclination angle of the first Fresnel lens relative to the optical axis on a plurality of non-optical effective surfaces in the central region is smaller than an average inclination angle of the first Fresnel lens relative to the optical axis on a plurality of non-optical effective surfaces in the edge region.

Virtual reality display device

The invention relates to a computer vision and an image processing technology. In order to propose a universal molar grain removing method, the molar grain removing method based on a plurality of pictures of the invention comprises the following steps: step 1, aligning images: converting all images taken on a screen to the same view angle; step 2, selecting a region without or with a slight molarripple to generate a corresponding mask {M1, M2,..., MM}, i.e., the pixel value of the selected region in the image is 1, the pixel value of the other region is 0, and the selected region should haveat least a few pixels overlapped so as to synthesize the whole image in the next step; step 3, image fusion: fusing the respective image regions selected in the previous step into a map IC, the pixelsof the overlapping portion being averaged to mitigate the boundary effect(shown in the specification) where sigma represents the image fusion operation. The invention is mainly applied to image processing occasions.

Moire removing method based on multiple graphs

The invention provides a method for decreasing Moire fringes in a glasses-free 3D directional backlight system. The method comprises: calculating Moire fringes generated on an LCD (liquid crystal display) screen when a Fresnel lens set and the LCD screen are under different angles, distances and cycle ratios, and drawing a graph; finding Fresnel lens set and LCD screen distance and angle optimal values from a visual contrast distribution graph for Moire fringes generated by Fresnel lens set and the LCD screen periodical information in the glasses-free 3D directional backlight system; constructing the 3D directional backlight system according to the found Fresnel lens set and LCD screen distance and angle optimal values. The method can decease Moire fringes without affecting the visual enjoinment from the glasses-free 3D system, and the quality of visual sensory views can be improved greatly.

Method for decreasing Moire fringes in glasses-free 3D directional backlight system

The invention discloses a Fresnel lens and a display device with the Fresnel lens The Fresnel lens comprises an incidence plane and an exitance plane, and the exitance plane is provided with multiple protrusion units, namely, the first protrusion unit, the second protrusion unit and the third protrusion unit The first protrusion unit, the second protrusion unit and the third protrusion unit are connected and distributed in sequence from the center axis of the lens to the emitting direction of the margin of the lens at one side of the center axis of the lens; the first protrusion unit, the second protrusion unit and the third protrusion unit are also connected and distributed in sequence from the center axis of the lens to the emitting direction of the margin of the lens at the other side of the center axis of the lens, and the two sides are distributed symmetrically According to the Fresnel lens and the display device with the Fresnel lens, the problem that the luminance of a Fresnel lens array is not uniform, and the moire fringes and margin luminance ladder problems exist can be solved or partially solved, and thus the purpose of optimizing a viewing effect is achieved

Fresnel lens and display device with Fresnel lens

The invention provides a naked-eye 3D Moire fringe eliminating device and a use method thereof. The device comprises a backlight source, a Fresnel lens array, an optical film layer, a liquid crystal panel and virtual receivers. After light which is emitted from a first light emitting unit and a second light emitting unit is refracted by the Fresnel lens array, focusing light with pseudo-periodicity is formed on an emergence plane of the Fresnel lens array. The focusing light with pseudo-periodicity arrives at the optical film layer. Distribution of light in a local area in which the optical film layer exists is changed, and original pseudo-periodicity is lost. But propagation direction of the light is not changed. Therefore after the optical film layer, the light is changed to the focusing light without pseudo-periodicity. The focusing light without pseudo-periodicity arrives at a sub-pixel grating of the liquid crystal panel and is divided into different colors. A first virtual receiver and a second virtual receiver collects light, and hereon the Moire fringe has been weakened.

Naked-eye 3D Moire fringe eliminating device and use method thereof

An ultra HD, low crosstalk, high luminance uniformity, and wide field of view auto-stereoscopic display is demonstrated with the use of novel free-form surface backlight array (FFSBA) and mix-teeth Fresnel lens (MTFL) technology, in conjunction with a hybrid spatial and temporal control scenario. The luminance uniformity is shown to be higher than 95.3% even within a wide viewing angle, and the minimum achievable crosstalk can be as small as 2.2%. The moire pattern is avoided by an equivalent anisotropic film (EAF).

Xian Yuqiao

Papers

Method for decreasing Moire fringes in glasses-free 3D directional backlight system

Fresnel lens and display device with Fresnel lens

Naked-eye 3D Moire fringe eliminating device and use method thereof

A high performance auto-stereoscopic display based on free-form surface backlight array and mix-teeth Fresnel lens