Process for producing microlens

A process for producing an image sensor, comprising, at least:

• a lens material film formation step in which a lens material is applied to a primary layer supported on a substrate to form a lens material film;
• a removed ditch formation step in which removed ditches are formed in the lens material film;
• a trench formation step in which etching is performed on the lens material film by using the lens material film having the removed ditches formed therein as a pattern mask to thereby form in the primary layer trenches corresponding to the removed ditches;
• and
• a microlens formation step in which portions of the lens material film supported on elevations, the elevations being portions of the primary layer in which the removed ditches are not formed, are melted by heat so that part of the lens material film flows along side walls of the trenches into the trenches to change a shape of the portions of the lens material film supported on the elevations and thereby form microlenses.