METHOD OF PRODUCTION OF OPTICAL PIECES WITH ASPHERIC SURFACES Russian patent published in 2005 - IPC

FIELD: opto-mechanical industry; production of optical component parts with aspheric surfaces in optical instrument-making field.

SUBSTANCE: the invention is dealt with the field of optical instrumentation technologies, in particular, the method may be used in an opto-mechanical industry for production of optical component parts with aspheric surfaces for devices of different assignment. The technical result is provision of a capability to form external and internal aspheric surfaces of optical component parts by pressing through layers of a glass, increased accuracy of manufacturing of aspheric surfaces, improvement of their optical qualities and reproducibility of results. Substance of the invention: the method provides for accommodation of a glass billet in the press mould consisting of the puncheon and a lower die, its warming up to the softening temperature, a deformation of glass billet by the puncheon under load and consequent machining. Deformation of the glass bullet is exercised by its pressing into a hollow lower die by the puncheon with an aspheric surface in depth of H = (0.05-0.4) D, where D is a diameter of the glass billet. The lower die is produced in the form of a bush with an internal diameter of ( 0.7-0.9 )D. An aspheric surface of the puncheon is defined with allowance for difference of coefficients of thermal expansion of the glass billet and the material of the puncheon, and also with regard to distribution of thickness of glass billet D₃ (r) formed after pressing along radial coordinate (r). The distribution is determined by the following formula: D₃(r) =t_bil· {K₀ + (1-K)/h(D/2) · h(r)},where h(r) - a required shape of the aspheric surface; h(D/2) - the depth aspheric shape at r=D/2; K₀ - factor of change of thickness in the center of the glass billet equal to_{to / tbil; where: tbil - thickness of the glass billet in the center of the billet before pressing; to - thickness of glass billet in the center after pressing.}

EFFECT: the invention ensures production of external and internal aspherical surfaces of optical components, increased accuracy of aspherical surfaces manufacture, improvement of their optical qualities and reproducibility of results.

5 cl, 1 dwg