Device having reflective and transmissive properties
View Patent ↗A device which simultaneously maximizes light reflectivity from one side of the device while maximizing light tansmmissivity from the opposite side of the device. The device is configured with distinct regions of transparency and reflectivity including a plurality of reflective structures. The structures generally smaller towards a light transmitting side of the device and larger towards a light reflective side of the device.
1. A device having transmissive and reflective properties produced by the process comprising the steps of:
providing a transparent photosensitive film;
providing a reflective metal layer on a surface of the photosensitive film;
removing the reflective metal layer in a predetermined region to expose the photosensitive film in the predetermined region; and
changing the optical characteristics of the photosensitive film in the predetermined region to alter the index of refraction of the photosensitive film in the predetermined region to thereby form an altered refractive index area.
2. The device of claim 1 , wherein an unchanged portion of the photosensitive film comprises an unaltered refractive index area.
3. The device of claim 2 , wherein the altered refractive index structure has a higher index of refraction than the unaltered refractive index area.
4. The device of claim 3 , wherein the ablating and changing steps occur in a plurality of predetermined regions thereby forming a plurality of altered refractive index areas.
5. The device of claim 4 , wherein the unchanged portion of the photosensitive film comprises a plurality of unaltered refractive index areas.
6. The device of claim 5 , wherein the unaltered refractive index areas are triangular cross-section structures each having a base, a height, and a pair of sidewalls each having an outside surface, the base is associated with said reflective metal layer, each sidewall is at an angle relative to said base.
7. The device of claim 1 , wherein said reflective metal layer has a desired reflectivity percentage.
8. A device having transmissive and reflective properties produced by the process comprising the steps of:
providing a photosensitive film having a first surface and a second surface;
forming a photoresist layer on the first surface of the photosensitive film;
changing the optical characteristics of the photosensitive film in a predetermined region by exposing the predetermined region of the film to a light source to alter the index of refraction of the film in the predetermined region to thereby form an altered refractive index area and to expose the photoresist layer in the predetermined region to the light source;
removing the exposed photoresist layer in the predetermined region using a suitable etchant creating an opening;
depositing a reflective metal layer in the opening previously occupied by the exposed photoresist layer; and
removing the remaining photoresist layer.
9. The device of claim 8 , wherein the light source is facing the second surface of the photosensitive film.
10. The device of claim 9 , wherein an unchanged portion of the photosensitive film comprises an unaltered refractive index area.
11. The device of claim 10 , wherein the altered refractive index area has a lower index of refraction than the unaltered refractive index area.
12. The device of claim 11 , wherein the changing step occurs in a plurality of predetermined regions thereby forming a plurality of altered refractive index areas.
13. The device of claim 12 , wherein the unchanged portion of the photosensitive film comprises a plurality of unaltered refractive index areas.
14. The device of claim 13 , wherein the unaltered refractive index areas are triangular cross-section structures each having a base, a height, and a pair of sidewalls, the base is associated with said reflective metal layer, each sidewall is at an angle relative to said base.
15. The device of claim 8 , wherein said reflective metal layer has a desired reflectivity percentage.