Manufacturing of a toroidal mold to elaborate polymeric lenses

Agustin Santiago-Alvarado¹Fermín Salomón Granados-Agustin²Oliver Carranza-Huerta^3*Víctor M Cruz-Martínez¹Jorge Alvarado-Martínez²Maximino Avendaño-Alejo³

• ¹División de Estudios de posgrado, Technological University of the Mixteca, Huajuapán de León, Mexico
• ²Instituto Nacional de Astrofisica Optica y Electronica, Puebla, Mexico
• ³Universidad Nacional Autonoma de Mexico, Mexico City, Mexico

The manufacture of optical molds to generate optical components in continuous or batch production, has become a great challenge since freeform components have been increasingly required. New manufacturing techniques have emerged to cope with such technological demands, however, freeform optics presents previously unseen manufacturing challenges, as traditional optical workshops are designed for producing components with spherical shape. The mold technique is widely used for batch production, but the main challenge is mold manufacturing. That is why the manufacturing process of a toroidal 6061 aluminum optical mold is presented, using a CNC milling machine. To evaluate the finish of the toroidal surface, null screen tests and coordinate measurement were used, since these tests allow to measure changes of slopes on the entire surface with a single evaluation, which with other tests is not possible. The results obtained show that it is feasible to implement it at a reduced cost, with errors of PV of 0.1806 mm and an RMS of 0.0402 mm in the surface finish, which can be reduced by taking the polishing stage as a guide.