ChromaDepth

Chromadepth is a patented system from the company Chromatek (a subsidiary of American Paper Optics since 2002) that produces a stereoscopic effect based upon differences in the diffraction of color through a special prism-like holographic film fitted into glasses. Chromadepth glasses purposely exacerbate chromatic aberration and give the illusion of colors taking up different positions in space, with red being in front, and blue being in back. This works particularly well with the sky, sea or grass as a background, and redder objects in the foreground.

With computer-controlled etching, the technology to create thin plastic sheets with thousands of microscopic ‘prism’ lenses that can magnify or diffract light can be made. Since violet light has more energy than red, and bends more when refracted, some lenses can distort an image if they don’t focus all of the colors at the same point. This distortion is called chromatic aberration.

One type of film etching creates lenses that deliberately exaggerate this aberration, separating the colors of an image into different convergence points in the visual field. It’s a patented process called ChromaDepth™. Glasses with ChromaDepth™ diffraction lenses create an artificial visual depth. “Warm” colors, toward the infrared end of the spectrum, appear closer, and ‘cool” colors toward the violet end appear further away.

Any media piece can be given a 3D effect as long as the color spectrum is put into use with the foreground being in red, and the background in blue. From front to back the scheme follows the visible light spectrum, from red to orange, yellow, green and blue. This means any color is associated in a fixed fashion with a certain depth when viewing. As a result, ChromaDepth works best with artificially produced or enhanced pictures, since the color indicates the depth.
(Natural images diminish the ChromaDepth™ effect because they reflect colors across the full spectrum, creating imaginary contours without explicit contrast. Artificially constructed or deliberately enhanced images exploit the forced color separation.)

Unlike anaglyph images or polarization, creating real-life ChromaDepth pictures without manual enhancement is practically impossible, since cameras cannot portray true depth; most other 3D schemes use the concept of stereopsis. However, this also gives ChromaDepth images a distinct advantage: unlike stereopsis-based schemes that require two images, ChromaDepth contains depth information in one image, which eliminates the ghosting seen in other schemes when one attempts to view them without 3D glasses. Thus, ChromaDepth images can be viewed comfortably and legibly without glasses, even though the 3D effect will not be perceivable without them.

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Wikipedia