ChromaDepth 3D glasses were invented by Richard Steenblik as a way to amplify the very slight chromostereoscopy phenomenon occasionally noticed by people who wear spectacles into a useful display tool. It gives viewers a depth effect when they are wearing the "double prism, refraction glasses."
To quote Erwin Verwichte and Klaus Galsgaard. "The lenses consist of two prisms placed face-to-face with their bases pointing in opposite directions." The two 'prisms' are both relatively low dispersion first order gratings. They shift colors differently. Red appears to be closer to a central line than blue. Where the line of sight converges depends on the color. This provides the optical illusion of seeing a 3D object.
To see the displacement effect of the ChromaDepth 3D glasses, a beam of red laser light was passed through the left and right eye pieces of the glasses. The laser beam appeared to shift to the left for the left eye piece and to the right for the right eye piece. The gratings act like prisms because most of the energy appears in the first order spectrum on one side.
The gratings have a saw-tooth profile with a groove spacing of
32 lines per mm. The
grating is said to be blazed. The ray refracts as it passes
through the plastic, which allows almost all of the energy to
appear in the first order spectrum on one side.
Publicity material from the suppliers contains the following ...
"ChromaDepth 3D is the only holographic 3D image display method ever created that can be applied in a color medium.... These remarkable glasses actually convert the colors in an image into holographic depth! The images are called Cyber Holograms. ChromaDepth 3D optics are water-clear. They incorporate a state-of-the-art system of micro-optics that actually create a holographic image from a single color image. ChromaDepth 3D optics act as a general purpose programmable hologram. A color image acts as a holographic program for the optics. color is the code used to program holographic depth information." (Emphasis added) Ed.
It is clear from the discussion above, that what the ChromaDepth glasses actually do, has nothing to do with holograms. In this sense, ChromaDepth 3D glasses are not "... a holographic 3D image display method."