Process for producing microlens array, array master, electrolytic solution and microlens array resin material therefor and apparatus for producing master

A process for producing a microlens array comprising the steps of:

• arranging a master substrate having an insulating substrate, an electroconductive thin film and a photosemiconductor thin film in this order;
• preparing an aqueous electrolytic solution containing a film forming material having a solubility or dispersibility in an aqueous liquid creasing upon changing pH;
• forming a microlens array master by contacting the photosemiconductor thin film and the electroconductive thin film with the aqueous electrolytic solution and irradiating the photosemiconductor thin film with a light so as to induce the pH change of the electrolyic solution enough to selectively deposit the film forming material on the master substrate;
• forming a layer of a template resin material on a surface of the master and releasing the layer therefrom to produce a template;
• and
• forming a layer of a microlens army resin material having a controlled refractive index on the template and releasing the template therefrom to produce a microlens array.

An apparatus for producing a microlens array master comprising:

• an exposure system comprising at least a light source for irradiating with light and an image formation optical system;
• a counter electrode;
• a unit capable of applying a bias voltage;
• and
• an electrodeposition bath having an electrolytic solution contained therein,
• wherein a substrate for forming a microlens array master is arranged in the electrodeposition bath to make at least the photosemiconductor thin film thereof in contact with the electrolytic solution.

An apparatus for producing a microlens array master comprising:

• a laser exposure system;
• a counter electrode;
• a unit capable of applying a bias voltage;
• and
• an electrodeposition bath having an electrolytic solution contained therein,
• wherein a substrate for forming a microlens array master is arranged in the electrodeposition bath to make at least the photosemiconductor thin film thereof in contact with the electrolytic solution.

A process for producing a microlens array forming master comprising the steps of:

• arranging a master substrate having an insulating substrate, an electroconductive thin film and a photosemiconductor thin film in this order;
• preparing an aqueous electrolytic solution containing a film forming material having a solubility or dispersibility in an aqueous liquid decreasing upon changing pH;
• and
• forming a microlens array master by contacting the semiconductor with the aqueous electrolytic solution and irradiating the photosemiconductor thin film with a light so as to induce the pH change of the electrolyic solution to selectively deposit the film forming material on the master substrate.