Manufacturing method of compound aspheric lens

1. A method of manufacturing a compound aspheric lens, comprising the steps of:

supplying nitrogen gas into a syringe for storing ultraviolet-curable resin fluid, and dropping the ultraviolet-curable resin fluid purged with the nitrogen gas onto an aspheric face of a metallic mold set horizontally, said aspheric face having a desired concave face;

bringing a convex lens to constitute the base of the aspheric lens close to the metallic mold and stopping the movement of the lens just before it comes into contact with the ultraviolet-curable resin fluid;

inclining the metallic mold and the lens together to cause the ultraviolet-curable resin fluid to flux;

after bringing the lens into contact with this fluxed and swelled ultraviolet-curable resin fluid in a narrow range, moving the lens to a prescribed position relative to the metallic mold to place the ultraviolet-curable resin fluid between the lens and the metallic mold;

returning the lens and the metallic mold together, with the ultraviolet-curable resin fluid held between them, from the inclined state to the horizontal state;

irradiating the ultraviolet-curable resin fluid with ultraviolet rays to cure the resin fluid; and

separating the molded resin layer that has been cured from its interface with the metallic mold.

2. The method of manufacturing a compound aspheric lens, as set forth in claim 1 , wherein an overall angle of inclination of said lens and metallic mold together is 30 to 40 degrees.

3. The method of manufacturing a compound aspheric lens, as set forth in claim 1 or 2 , wherein the aspheric face of said metallic mold is plated with nickel.

4. The method of manufacturing a compound aspheric lens, as set forth in claim 1 or 2 , wherein said ultraviolet-curable resin fluid is a photopolymeric acrylate-based ultraviolet-curable resin fluid that is cured by a radical polymeric reaction to irradiation with ultraviolet rays.

5. The method of manufacturing a compound aspheric lens, as set forth in claim 1 or 2 , wherein a viscosity of said ultraviolet-curable resin fluid is 1000 to 2500 cps.

6. A method of manufacturing a compound aspheric lens, comprising the steps of:

supplying nitrogen gas into a syringe for storing ultraviolet-curable resin fluid, and dropping the ultraviolet-curable resin fluid purged with the nitrogen gas onto a concave face of a concave lens which is to constitute the base of an aspheric lens set horizontally;

dropping the ultraviolet-curable resin fluid purged with said nitrogen gas onto a central part of an aspheric face of a metallic mold, the mold having a desired convex aspheric face, the face being directed upward, and the fluid being dropped in a quantity small enough not to drop off when the mold is inverted;

turning the metallic mold upside down and placing it over said lens;

bringing the resin fluid on the concave face of the lens and the tip of the resin fluid on the aspheric face of the metallic mold close enough to come into contact with each other;

narrowing the gap between the lens and the metallic mold to a prescribed extent to place the resin fluid between them;

curing the resin fluid between the lens and the metallic mold by irradiation with ultraviolet rays; and

separating the molded resin layer that has been cured from its interface with the metallic mold.

7. The method of manufacturing a compound aspheric lens, as set forth in claim 6 , wherein the quantity of the ultraviolet-curable resin fluid 10 dropped onto the side to be turned upside down is about 1 to 2 mm per drop and one drop thereof is dripped.

8. The method of manufacturing a compound aspheric lens, as set forth in claim 6 or 7 , wherein said ultraviolet-curable resin fluid is a photopolymeric acrylate-based ultraviolet-curable resin fluid that is cured by a radical polymeric reaction to irradiation with ultraviolet rays.

9. The method of manufacturing a compound aspheric lens, as set forth in claim 6 or 7 , wherein a viscosity of said ultraviolet-curable resin fluid is 1000 to 2500 cps.