Method of manufacturing a microlens substrate, an opposed substrate for a liquid crystal panel, a liquid crystal panel and a projection type display apparatus

A method of manufacturing a microlens substrate, the microlens substrate being provided with a plurality of microlenses, the method comprising the steps of:

• preparing a concavity substrate, the concavity substrate having first and second major surfaces, the first major surface having a plurality of concave portions formed therein, each of the plurality of concave portions having a shape corresponding to that of each of the plurality of microlenses;
• preparing a base material substrate mainly formed of a thermoplastic resin material in a state where all of the monomers constituting the thermoplastic resin material have not reacted so that the thermoplastic resin material is not completely hardened, the base material substrate having third and fourth major surfaces, the third major surface being opposite to the fourth major surface, the third major surface facing the first major surface;
• and subjecting the first major surface of the concavity substrate on which the plurality of concave portions are formed to surface treatment for improving adhesion to the resin material, wherein the surface treatment is a vapor process using 3-glycidoxypropyltrimethoxysilane or 3-aminopropyltrimethoxysilane;
• pressure-joining the concavity substrate to the base material substrate in a state that the concavity substrate and the base material substrate are being heated under a pressure of 10 Pa or less while the fourth major surface of the base material substrate is simultaneously being cooled, wherein in the pressure-joining step, the concavity substrate is joined to the base material substrate so that the plurality of concave portions are filled with the resin material of the base material substrate which is melted by the heat.