SPATIAL DEPOSITION OF RESINS WITH DIFFERENT FUNCTIONALITY
Techniques disclosed herein relate to optical devices. Resins with different optical properties can be deposited in different areas to provide increased optical functionality. It can be difficult to design a single photopolymer material that meets several technical requirements. Different resins can be deposited on the same substrate to make a single film with spatially varying properties. Different resins can also be applied to different substrates in a stack. By using different resins, an optical component can be made that meets several technical requirements.
1 . A device comprising:
a first holographic recording material disposed on a substrate, wherein the first holographic recording material comprises a first optical element;
a second holographic recording material disposed on the substrate, wherein:
the second holographic recording material comprises a second optical element; and
the second optical element is smaller in size than the first optical element based on a property of the second holographic recording material compared to a property of the first holographic recording material.
2 . The device of claim 1 , wherein a refractive index of the first holographic recording material is substantially the same as a refractive index of the second holographic recording material.
3 . The device of claim 1 , wherein the first optical element and the second optical element are volume Bragg gratings.
4 . The device of claim 3 , wherein the second optical element is smaller in size than the first optical element by having a smaller pitch than the first optical element.
5 . The device of claim 1 , wherein the first holographic recording material is disposed on the substrate in a first pattern that at least partially overlaps a second pattern of the second holographic recording material disposed on the substrate.
6 . A method comprising:
depositing a first material on a substrate, wherein the first material forms a first pattern on the substrate;
depositing a second material on the substrate, wherein:
the second material forms a second pattern on the substrate; and
the first pattern at least partially overlaps the second pattern; and
exposing the first material and the second material to light to form a first optical element in the first material and a second optical element in the second material, wherein the second optical element is smaller than the first optical element.
7 . The method of claim 6 , wherein a refractive index of the first material is substantially the same as a refractive index of the second material.
8 . The method of claim 6 , wherein:
the first material has a first diffusion coefficient;
the second material has a second diffusion coefficient; and
the first diffusion coefficient is greater than the second diffusion coefficient.
9 . The method of claim 6 , wherein the first optical element and the second optical element are holographic Bragg gratings.
10 . The method of claim 6 , wherein the first material has a different spatial frequency response than the second material.
11 . A method comprising:
applying a first material to a substrate, wherein:
the first material comprises a first matrix, a first monomer, and a first photoinitiator;
the first monomer is a writing monomer configured to polymerize based on a reaction with the first photoinitiator; and
the first material is characterized by a first diffusion coefficient of the first monomer in the first matrix;
applying a second material to the substrate, wherein:
the second material comprises a second matrix, a second monomer, and a second photoinitiator;
the second monomer is a writing monomer configured to polymerize based on a reaction with the second photoinitiator;
the second material is characterized by a second diffusion coefficient of the second monomer in the second matrix; and
the second diffusion coefficient is less than the first diffusion coefficient; and
exposing the first material and the second material to light to form optical elements in the first material and in the second material.
12 . The method of claim 11 , wherein:
the first matrix has a first refractive index;
the second matrix has a second refractive index; and
the first refractive index is substantially the same as the second refractive index.
13 . The method of claim 12 , wherein there is less than a 0.001 difference between the first refractive index and the second refractive index.
14 . The method of claim 11 , wherein the optical elements comprise a first grating in the first material, the first grating having a first pitch, and a second grating in the second material, the second grating having a second pitch.
15 . The method of claim 14 , wherein the first pitch is larger than the second pitch based on the first diffusion coefficient being greater than the second diffusion coefficient.
16 . The method of claim 11 , wherein the first matrix and the second matrix are resins while applied to the substrate.
17 . The method of claim 11 , further comprising depositing the first material and the second material with an ink-jet dispenser.
18 . The method of claim 11 , further comprising depositing the first material and the second material on the substrate to form a concentration gradient of the first material and the second material.
19 . The method of claim 11 , wherein
the first material and the second material are holographic recording materials; and
the optical elements form a volume Bragg grating.
20 . The method of claim 11 , wherein:
the optical elements comprise a first optical element in the first material and a second optical element in the second material; and
the second optical element is smaller in size than the first optical element.