Sony shows four-layer Micro-Reflector holographic recording technique
Sony looks to be quite serious with its achievements with holographic recording. Now, they have managed to get data reading/writing on a medium alike to four-layer disc, thanks to the Micro-Reflector recording technique. The company claims that this new method will prevent any sort of signal reading errors as the expansion/contraction of photopolymer due to heat will have negligible effect on the whole process.
The recording density per layer is 1.25 GB in terms of a 12 cm-disk capacity thereby offering a total of 5 GB for four layers. In the process, a light emanated from a blue-violet semiconductor laser diode (405 nm wavelength) is split into two in order to irradiate the recording medium on both sides. The number of recording layers was increased by adding optical parts to vary the focal point depth
But, a major problem in this technique is that the reproduction signal gets weaker in the deeper layer that could result in slower data transfer speeds. Sony needs to address this problem if they really wish to accomplish 500 GB recording density with twenty layers each of 25 GB density.
Via: techon
