Abstract: With regard to an eyeglass lens that is provided with a plurality of defocus regions on at least one of an object-side surface and an eyeball-side surface, the surface shape is evaluated through measuring the surface shape of the surface of the eyeglass lens that has the plurality of defocus regions, and acquiring three-dimensional data regarding the surface shape; a classifying data groups regarding the plurality of respective defocus regions and a data group regarding a base region, which is a region where the defocus regions are not formed, by performing cluster analysis on the three-dimensional data; combining curved surface shape data obtained by performing curve fitting on each of the classified data groups, and extracting reference shape data regarding the object-side surface; and comparing the three-dimensional data and the reference shape data, and obtaining degrees of deviation of the three-dimensional data from the reference shape data.

Abstract: A foil transfer device includes a first projector projecting light toward a foil film, and a second projector projecting light toward the foil film. The second projector and the first projector are staggered relative to each other.

Abstract: A method and apparatus for optimizing a lens of a virtual reality device and a computer readable storage medium. The method for optimizing a lens of a virtual reality device includes setting an optimization objective and optimization variables for imaging with a lens; and performing optimization processing on the imaging of an object point through the lens by the optimization variables, and obtaining a lens parameter value by which the imaging result is in accordance with the optimization objective, an image surface of the imaging of the object point through the lens being an image surface on which the astigmatism is less than a preset threshold.

Abstract: A curved Fresnel lens is provided. The Fresnel lens includes a grooved surface and a smooth surface. The grooved surface includes a plurality of concentric sloped facets and a plurality of concentric draft facets. Pairs of concentric draft facets and concentric sloped facets form a plurality of concentric grooves in the grooved surface. The concentric sloped facets are configured to focus light toward an eye of a nominal user. At least some of the concentric draft facets are congruent with conical surfaces of respective imaginary light cones that have corresponding vertices that originate from respective focal points, wherein each imaginary light cone extends through the Fresnel lens at an angle based in part on an index of refraction of the Fresnel lens and extends beyond the grooved surface into free space.

Abstract: A backlight unit includes a light source and a lens unit optically coupled to the light source. A surface of the lens unit facing the light source includes areas coated with a reflective material for reflecting light from the light source away from the lens, and a transmissive area for transmitting light from the light source towards ran output surface of the lens. A display device includes a display panel, a light diffuser, the backlight unit and a reflective element, the backlight unit arranged between the light diffuser and the reflective element, and the display panel positioned opposite the backlight unit with respect to the light diffuser.

Abstract: A method for designing an imaging device. The method comprises receiving specification of a final image mapping a three-dimensional environment according to a predefined mapping and an optical unit with an optical aberration. The method further comprises estimating an optical design of the optical unit with the optical aberration. The optical unit is configured for projecting a uncorrected initial image according to the optical aberration. The method further comprises calculating an algorithmic correction for the uncorrected initial image. The algorithmic correction is designed for compensating for the effect of the optical aberration on the uncorrected initial image. The method further comprises manufacturing the imaging device. The manufactured imaging device having the optical design and applying the algorithmic correction on the uncorrected initial image, thereby outputting the final image without the effect produced by said optical aberration and with said predefined mapping.

Abstract: A projection television set includes a body composed of at least two divided upper and lower units, a screen assembly having an integrally formed screen corresponding to the body, and a plurality of bolt and nut assemblies for coupling the divided units together. Each of the upper and lower units has a projector for emitting light rays for forming an image on a screen and a reflector for reflecting the light rays from the projector onto the screen. The projector of the lower unit is arranged below the reflector of the lower unit, and the projector of the upper unit is arranged in an intermediate position between the reflector of the upper unit and the reflector of the lower unit so that setting angles of the two reflectors are different from each other. A screen assembly is mounted on a front face of the body.