Obscuring bus bars in electrochromic glass structures
Embodiments described include bus bars for electrochromic or other optical state changing devices. The bus bars are configured to color match and/or provide minimal optical contrast with their surrounding environment in the optical device. Such bus bars may be transparent bus bars.
1. An electrochromic window comprising:
a transparent substrate including a surface upon which an electrochromic device is disposed, the electrochromic device comprising a plurality of layers, the plurality of layers including a transparent conductive layer sandwiched between the transparent substrate and the remainder of the plurality of layers;
a bus bar disposed on the transparent conductive layer; and
an obscuration layer between the transparent conductive layer and the transparent substrate, the obscuration layer at least registered with the bus bar so as to obscure the bus bar from view through the transparent substrate.
2. The electrochromic window of claim 1 , wherein the obscuration layer is opaque.
3. The electrochromic window of claim 1 , wherein the obscuration layer has an area on the transparent substrate that is larger than that of the bus bar.
4. The electrochromic window of claim 1 , wherein the obscuration layer is between about 1 nm and 500 nm thick.
5. The electrochromic window of claim 1 , wherein the obscuration layer is between about 1 nm and 100 nm thick.
6. The electrochromic window of claim 1 , wherein the obscuration layer is between about 1 nm and 10 nm thick.
7. The electrochromic window of claim 1 , wherein the obscuration layer comprises a material having the same or similar color to a sealant between the transparent substrate and a spacer of an insulated glass unit comprising the electrochromic window.
8. The electrochromic window of claim 1 , further comprising a diffusion barrier disposed between the transparent substrate and the transparent conductive layer.
9. The electrochromic window of claim 1 , wherein the obscuration layer comprises a metal oxide or a metal material.
10. The electrochromic window of claim 9 , wherein the obscuration layer is sputter-deposited.
11. The electrochromic window of claim 1 , wherein the transparent conductive layer is indium tin oxide.
12. The electrochromic window of claim 8 , wherein the obscuration layer is between the diffusion barrier and the transparent substrate.
13. The electrochromic window of claim 1 , wherein the obscuration layer is wider than the bus bar.
14. The electrochromic window of claim 1 , wherein the obscuration layer is a tinted coating.
15. The electrochromic window of claim 1 , wherein the obscuration layer is selectively applied to an area within the area of the transparent substrate.
16. The electrochromic window of claim 1 , wherein the obscuration layer is applied to the transparent substrate and selectively removed from areas of the transparent substrate thereafter.
17. The electrochromic window of claim 16 , wherein selective removal comprises using a laser or a plasma.