초록 ▼

A method for making optical preforms of optical elements without residual stress or distortion is provided. In this method, an optical material is supplied between upper and lower molds. The upper mold has a plurality of recesses arranged in a predetermined pitch, and each recess corresponds to a fi

A method for making optical preforms of optical elements without residual stress or distortion is provided. In this method, an optical material is supplied between upper and lower molds. The upper mold has a plurality of recesses arranged in a predetermined pitch, and each recess corresponds to a first surface shape of the optical element. The lower mold has a plurality of recesses facing the recesses of the upper mold and each recess of the lower mold corresponds to a second surface shape of the optical element. The supplied optical material is pressed between the upper and lower molds to be a set of optical preforms. The set of optical preforms is processed by die punching or tool cutting to separate each optical preform from the set of optical preforms. Each optical preform is used for producing an optical element by further pressing. Alternatively, optical element can be formed directly by the press molding process.

대표청구항 ▼

[ What is claimed is:] [1.] A method for making optical preforms of optical elements by processing an optical material, the method comprising steps of:supplying said optical material made of a plastic material between upper and lower molds, said upper mold having a plurality of recesses arranged in

[ What is claimed is:] [1.] A method for making optical preforms of optical elements by processing an optical material, the method comprising steps of:supplying said optical material made of a plastic material between upper and lower molds, said upper mold having a plurality of recesses arranged in a predetermined pitch, each recess corresponding to a first surface shape of said optical element, said lower mold having a plurality of recesses facing said recesses of the upper mold, each recess of the lower mold corresponding to a second surface shape of said optical element;pressing said optical material to form a set of optical preforms; andseparating each optical preform from said set of optical preforms.