Method for forming multiply patterned optical articles
View Patent ↗The present invention provides a solution to the needs described above through a method for forming multiply patterned optical articles. The method comprises providing a micromold having a pre-patterned surface structure, disposing a photorecording medium comprising a matrix precursor and a photoactive monomer on a holder surface, moving the micromold to the photorecording medium on the holder surface such that the pre-patterned surface structure contacts the photorecording medium, wherein the photorecording medium conforms to the pre-patterned surface structure of the micromold, at least partially curing the photorecording medium adherent while the micromold pre-patterned surface structure contacts the photorecording medium, and further patterning the photorecording medium by irradiating the photorecording medium with laser light to polymerize the photoactive monomer.
1. A method for forming an optical article comprising: providing a micromold having a pre-patterned surface structure;
disposing a photorecording medium comprising a matrix precursor and a photoactive monomer on a holder surface;
moving the micromold to the photorecording medium on the holder surface such that the pre-patterned surface structure contacts the photorecording medium, wherein the photorecording medium conforms to the pre-patterned surface structure of the micromold;
at least partially curing the photorecording medium adherent while the micromold pre-patterned surface structure contacts the photorecording medium;
further patterning the photorecording medium by irradiating the photorecording medium with laser light to polymerize the photoactive monomer.
2. The method of claim 1 , wherein irradiating the photorecording medium with laser light to polymerize the photoactive monomer comprises recording regions of interference fringes of volume phase hologram diffraction gratings.
3. The method of claim 1 , wherein the micromold pre-patterned surface structure forms an optical waveguide structure on the photorecording medium when the photorecording medium conforms to the pre-patterned surface structure of the micromold.
4. The method of claim 1 , further comprising disposing an optical phase grating adjacent to the photorecording medium and applying the laser light through the optical phase grating to the photorecording medium.
5. The method of claim 4 , wherein the optical phase grating comprises a surface relief structure fabricated in a high quality diffractive optic transparent to the laser beam.
6. The method of claim 1 , further comprising interfering multiple optical laser beams through the photorecording medium.
7. The method of claim 1 wherein the resulting structure is an optical filter, multiplexer, demultiplexer, holographic lens, or other phase structure embedded within an optical waveguide.
8. The method of claim 1 , wherein the polymer matrix comprises a polyether backbone.
9. The method of claim 1 , wherein the photoactive monomer is selected from vinyl aromatic compounds.
10. The method of claim 1 , wherein the photoactive monomer is at least one of styrene, bromostyrene, divinyl benzene, and 4-methylthio-1-vinylnaphth-alene.
11. The method of claim 1 , wherein a photoinitiator is mixed with the matrix precursor and photoactive monomer.
12. The method of claim 1 , further comprising removing the micromold prior to further patterning the photorecording medium by irradiating the photorecording medium with laser light.
13. The method of claim 1 , wherein one or more photoactive monomers comprises a moiety, other than the monomer functional group, that is substantially absent from the polymer matrix.