Abstract: A method for producing light-guide optical elements (LOEs) (16, 18, 56, 58) each having a set of mutually-parallel partially-reflecting surfaces (17) located between, and oriented non-parallel to, a pair of major external surfaces, and at least one region (30a, 30b, 30c) without partially-reflecting surfaces. The method includes bonding together parallel-faced plates (4) at interfaces to form a stack (42) of plates with partially-reflecting coatings between them. The stack is cut and polished to form a boundary plane (48, 48a, 48b) intersecting the interfaces, and a block (50, 50a, 50b) of transparent material is bonded to the stack. The resulting precursor structure (52, 52?) is sliced along parallel planes to form slices, each containing a part of the stack for the active region of the LOE and a part of the block.

Abstract: A method and a system for distributing coupons for buying articles enabling a first user to provide a second user with an entitlement to a coupon, enabling the second user to obtain the coupon providing a price reduction for buying an article, and, upon the purchase of the article using the coupon, providing a commission to the first user.