Following Collier et all* that probably would not run. Let us take ideal material, which has exact fourier-shape layers of diffraction picture. There is finite (i.e. >0) bandwidth of the reflected spectrum. It depends upon bragg's angle, refraction index of the plate, thickness of the holographic layer and laser wavelength (also depends upon your experiment scheme, details are in chapter 17.6 of the mentioned book). For example 7 nm for 633 nm. laser and 80 degrees bragg angle. It is not extinct. So, if the tunable laser has minimal step LESS than this criteria, you may get cross modulation effect.unixboy wrote:Martin wrote: Let's daydream a little bit for fun. We could have a theoretical ideal holographic recording medium, which is panchromatic sensitive and has zero absorption in whole visible spectrum and we have a tunable wavelength (400nm-760nm) SLM laser. We make 180 layers of such emulsion, which is 10 micron thickness per layer and we make (760-400)/2=180 laser exposures (2nm step of laser wavelengths), then we stack them all together, the total thickness is 10micron * 180=1800 micron=1.8 mm. Such 1.8mm thick multi-layer-multi-wavelength hologram should give us: high brightness and high color saturation as the real objects. That's the real virtual reality.
*R.J.Collier, C.B.Burckhardt, L.H.Lin "Optical Holography", 1971 edition, chapter 17.6
Vladimir B.