Latent holographic media and method
View Patent ↗A holographic recording medium having a polymer matrix comprising a developer, wherein the holographic recording medium is capable of recording a latent hologram and the developer is capable of developing the latent hologram into a readable hologram by activation of the developer is disclosed. The holographic recording medium is capable of storing large numbers of holograms in the same volume with better signal resolution than previous holographic media by first recording a multitude of latent (or very weak) holograms in the same volume of space, then applying preferably a non-chemical fixing step to develop the latent holograms into readable holograms. The holographic recording medium and method of this invention cause the holograms to increase in diffraction efficiency, thus preventing complications caused during recording of holograms whereby previously recorded holograms interfere with latter recorded holograms in the same volume of space within the media.
1. A medium comprising:
a polymer matrix,
a monomer comprising an attachment functionality to which the developer attaches upon activation,
a photoinitiator, and
a developer,
wherein the medium is capable of recording a latent hologram and the developer is capable of developing the latent hologram into a readable hologram by activation of the developer.
2. The medium of claim 1 , wherein the latent hologram represents less than 10% of the final diffraction efficiency after developing.
3. The medium of claim 1 , wherein the latent hologram represents 10% to 80% of the final diffraction efficiency after developing.
4. The medium of claim 1 , wherein the medium comprises a non-photoactive matrix or a photoactive matrix, and the medium further comprises a material selected from the group consisting of an oligomer, a photoactive chemical and combinations thereof.
5. The medium of claim 1 , wherein the activation of the developer comprises heat, light sonication, or particle radiation.
6. The medium of claim 1 , wherein the activation of the developer is by exposure to light.
7. The medium of claim 6 , wherein the activation of the developer by light is accomplished by a light of a different wavelength than a recording light wavelength.
8. A medium comprising:
a polymer matrix comprising reactive sites,
a photoactive chemical comprising attachment sites, and
a developer,
wherein the photoactive chemical bonds to the matrix reactive sites during recording and the developer bonds to the attachment sites of the photoactive chemical bonded to the polymer matrix during activation of the developer.
9. The medium of claim 8 , wherein the activation of the developer comprises heat, light sonication, or particle radiation.
10. The medium of claim 8 , wherein the activation of the developer is by exposure to light.
11. The medium of claim 10 , wherein the activation of the developer by light is accomplished by a light of a different wavelength than a recording light wavelength.