Lens Blocking and Deblocking Method and Related Device

Abstract

A method for blocking and/or deblocking an optical lens ( 100 ) on a heat conducting holding unit ( 200 ) comprising an upper assembling surface ( 210 ) comprising the steps of: a) providing first layer consisting of an adhesive tape ( 330 ) on the upper assembling surface ( 210 ) of the holding unit; b) providing a second layer consisting of a layer ( 310 comprising a thermoplastic material arranged on said adhesive tape ( 330 ); c) providing the optical lens ( 100 ) with a third layer consisting of an adhesive tape ( 320 ) arranged on the bottom surface ( 120 ) of said optical lens; d) placing the optical lens ( 100 ) with the third layer ( 320 ) on the second layer ( 310 ) consisting of a layer comprising a thermoplastic material when the thermoplastic material is soften or melted. A method for deblocking said optical lens ( 100 ) thanks to heating the holding unit ( 200 ).

1 . A method for blocking an optical lens on a heat conducting holding unit comprising a bottom part to be inserted and fixed in a lens machining tool and an upper part comprising an upper assembling surface, wherein the method comprises the steps of:
 a) providing first layer having an adhesive tape on the upper assembling surface of the holding unit;   b) providing a second layer having a layer comprising a thermoplastic material arranged on said adhesive tape;   c) providing the optical lens with a third layer having an adhesive tape arranged on the bottom surface of said optical lens; and   d) placing the optical lens with the third layer on the second layer having a layer comprising a thermoplastic material when the thermoplastic material is soften or melted.   
     
     
         2 . An optical lens blocking device comprising:
 a heat conducting holding unit comprising a bottom part to be inserted and fixed in a lens machining tool and an upper part comprising an upper assembling surface;   a first layer having an adhesive tape placed on the upper assembling surface of the holding unit;   a second layer having a layer comprising a thermoplastic material stacked on the first layer; and   a third layer having an adhesive tape stacked on the second layer   
     
     
         3 . The optical lens blocking device of  claim 2 , wherein the upper assembling surface of the holding unit is a spherical surface. 
     
     
         4 . The optical lens blocking device of  claim 2 , wherein the melting or softening point of the thermoplastic material of the second layer is between 45° C. and 75° C. 
     
     
         5 . The optical lens blocking device of  claim 2 , wherein the adhesive tapes have a pressure-sensitive adhesive surface arranged to contact a bottom surface of an optical lens on the upper assembling surface of the holding unit and a tack-free adhesion promoting surface arranged to contact the surfaces of the second layer. 
     
     
         6 . The optical lens blocking device of  claim 2 , wherein the thickness of the second layer is between 0.5 mm and 2 mm. 
     
     
         7 . A method for deblocking an optical lens comprising a bottom surface, which bottom surface is secured on an optical lens blocking device according to  claim 2  comprising the steps of:
 a) heating the holding unit so as to soften or melt the thermoplastic material of the second layer; 
 b) separating the bottom surface of the second layer from the upper surface of the adhesive tape of the first layer; and 
 c) separating the bottom surface of the optical lens from the upper surface of the adhesive tape of the third layer. 
 
     
     
         8 . The deblocking method of  claim 7 , further comprising the steps of:
 d) separating the bottom surface of the adhesive tape of the third layer from the upper surface of the second layer; and   e) separating the bottom surface of the adhesive tape of the first layer from the upper assembling surface of the holding unit.   
     
     
         9 . The deblocking method of  claim 7 , wherein step a) of the deblocking method consists in heating only the bottom part of the holding unit. 
     
     
         10 . A method of machining an optical lens having a bottom surface comprising the steps of:
 blocking the bottom surface of the optical lens on the optical lens blocking device of  claim 2 ;   inserting and fixing the bottom part of the holding unit in a lens machining tool;   machining the upper surface of the optical lens and/or edging said optical lens; and   deblocking the machined optical lens the bottom surface of which is secured on said optical lens blocking device, comprising the steps of:   a) heating the holding unit so as to soften or melt the thermoplastic material of the second layer;   b) separating the bottom surface of the second layer from the upper surface of the adhesive tape of the first layer; and   c) separating the bottom surface of the optical lens from the upper surface of the adhesive tape of the third layer.   
     
     
         11 . A method for deblocking an optical lens which bottom surface is blocked according to  claim 1  comprising the steps of:
 a) heating the holding unit so as to soften or melt the thermoplastic material of the second layer; 
 b) separating the bottom surface of the second layer from the upper surface of the adhesive tape of the first layer; 
 c) separating the bottom surface of the optical lens from the upper surface of the adhesive tape of the third layer. 
 
     
     
         12 . A method of machining an optical lens having a bottom surface comprising the steps of:
 blocking the bottom surface of the optical lens according to  claim 1 ;   inserting and fixing the bottom part of the holding unit in a lens machining tool;   machining the upper surface of the optical lens and/or edging said optical lens; and   deblocking the machined optical lens according to the steps of:
 a) heating the holding unit so as to soften or melt the thermoplastic material of the second layer; 
 b) separating the bottom surface of the second layer from the upper surface of the adhesive tape of the first layer; and 
 c) separating the bottom surface of the optical lens from the upper surface of the adhesive tape of the third layer. 
   
     
     
         13 . The optical lens blocking device of  claim 6 , wherein the thickness of the second layer is equal to or less than 1 mm.