in this case the monobloc obtained previously must be strengthened by laminating one or more layers of a stronger plastic to it a first option consists in adding fig4 f a sheet 16 and 19 of strong plastic on each side in a second option fig5 d a single layer 16 of strong plastic is added plastics of softening points greater than 150 u00b0 c such as polycarbonate pc or polyethylene terephthalate pet provide the necessary mechanical strength increasing the strength to 15 000 bending cycles instead of the 1 000 bending cycles generally encountered with a traditional prelaminated assembly a second mode of realisation of the invention is illustrated on fig4 a 4b 4 c 4 d 4 e and 4 f a cavity 20 is machined in a first support 10 fig4 a this cavity 20 is large enough to insert a module 11 a second support 16 is positioned under the first support and a drop of resin 17 is deposited in the cavity formed by the first and second supports as an alternative the cavity machined in support 10 can be a blind hole the drop of resin then being deposited at the bottom of this hole after depositing the resin 17 module 11 is positioned in the cavity fig4 c the.