Evanescent Lens

Description
This lens allows the wearer to see through a 3x3x1 wall even if the other side is blocked. Certain objects such as chests and the like cannot be seen through and are instead opaque.

Thaumonomicon Entry
"'Light cannot penetrate most forms of matter, but magic is not so easily stopped. You have designed a lens capable of 'pulling' light short distances through the thaumic field, allowing you to see through a 3x3 square of blocks.""Unfortunately, the light waves suffer decoherence when passing through certain complex objects and so such blocks will remain opaque.'"