High refractive index and highly birefringent solid organic materials
An organic thin film includes an organic solid crystal material and has mutually orthogonal refractive indices, n x , n y , and n z each having a value at 589 nm of between approximately 1.5 and approximately 2.6, where n x ≠n y ≠n z . The organic thin film may be birefringent, and may be configured as a single layer thin film, or plural organic thin films may be stacked to form a multilayer that may be incorporated into an optical element, such as a reflective polarizer.
1. An organic thin film comprising an organic solid crystal material, the organic thin film having mutually orthogonal refractive indices (n x , n y , n z ), wherein n x , n y , and n z each have a value at 589 nm of between approximately 1.5 and approximately 2.6, and n x ≠n y ≠n z , wherein the organic solid crystal material comprises an organic molecule selected from the group consisting of 1,2,3-trichlorobenzene, 1,2-diphenylethyne, phenazine, terphenyl, 1,2-bis(4-(methylthio)phenyl)ethyne, and anthracene.
2. The organic thin film of claim 1 , wherein the organic solid crystal material comprises a single crystal material or a polycrystalline material.
3. The organic thin film of claim 1 , wherein the organic solid crystal material comprises a glassy material having molecules aligned along predetermined directions.
4. The organic thin film of claim 1 , wherein Δn xy =Δn xz <Δn yz or Δn xy =Δn yz <Δn xz .
5. The organic thin film of claim 1 , wherein n z is at least approximately 1.8 and the organic thin film has an out-of-plane birefringence of at least approximately 0.2.
6. The organic thin film of claim 1 , wherein the organic solid crystal material is at least approximately 80% crystalline.
7. The organic thin film of claim 1 , wherein a surface of the thin film comprises a profile selected from the group consisting of planar, convex, and concave.
8. An optoelectronic device comprising an organic multilayer thin film, wherein each layer in the organic multilayer thin film comprises the organic thin film of claim 1 .