The wafer-level manufacturing method makes possible to manufacture ultrathin optical devices such as opto-electronic modules. A clear encapsulation is applied to an initial wafer including active optical components and a wafer-size substrate, thereon, a photostructurable opaque coating is produced which includes apertures. Then, trenches are produced which extend through the clear encapsulation and establish side walls of intermediate products. Then, an opaque encapsulation is applied to the intermediate products, thus filling the trenches. Cutting through the opaque encapsulation material present in the trenches, singulated optical modules are produced, wherein side walls of the intermediate products are covered by the opaque encapsulation material.