Method for precision alignment during a blocking process of lens manufacturing

Abstract

A blocking apparatus and a blocking method allow precise alignment of an axis of a button with an axis of a block for a blocking process of lens manufacturing. According to another aspect, the invention provides a blocking apparatus and a blocking method for automatically compensating variations in button geometry without requiring complex adjustments during the blocking process of lens manufacturing. According to yet another aspect, the invention provides a button holder that may adjustably float on a seat stage of a blocking apparatus, where the button holder may include a mechanism to self-align on the seat stage after a block of the blocking apparatus interfaces with the button holder.

1 . A method for aligning a block with a work piece, the method comprising: 
 providing a work-piece holder;    coupling an alignment pin to a block head;    displacing the work-piece holder or the alignment pin along an axis to bring the work-piece holder into engagement with and into alignment with the alignment pin;    placing a work piece in the work-piece holder;    substituting a block for the alignment pin in the block head; and    displacing the work-piece holder or the block along the axis to bring the work-piece into contact with the block and to fix the work piece to the block.    
   
   
       2 . The method of  claim 1 , wherein the work-piece holder is displaceably mounted on a seat stage such that it can be displaced in a plane orthogonal to the axis of displacement of the work-piece holder or alignment pin.  
   
   
       3 . The method of  claim 2 , wherein the work-piece holder is displaced in the plane when the alignment pin engages the work-piece holder as a result of the engagement.  
   
   
       4 . The method of  claim 3 , wherein the plane in which the work-piece holder is displaced is a horizontal plane  
   
   
       5 . The method of  claim 1 , wherein the work piece is placed in a recess of the work-piece holder.  
   
   
       6 . The method of  claim 1 , wherein the work-piece holder is adjustably positioned on a seat stage.  
   
   
       7 . The method of  claim 6 , wherein the work-piece holder is adjustably positioned in a cavity defined by the seat stage.  
   
   
       8 . The method of  claim 1 , wherein the work-piece holder defines an air space, and wherein the method further comprises regulating air pressure inside the air space of the work-piece holder to hold the work piece in place on the work-piece holder.  
   
   
       9 . The method of  claim 1 , wherein the block head is displaced along a vertical axis to displace the block and the alignment pin.  
   
   
       10 . The method of  claim 9 , further comprising controlling the displacement of the block head with a controlling mechanism.  
   
   
       11 . The method of  claim 1 , wherein the work piece is an unprocessed lens.  
   
   
       12 . The method of  claim 1 , wherein the work-piece holder is coupled with the seat stage via one or more fastening mechanisms.  
   
   
       13 . The method of  claim 12 , wherein the fastening mechanisms permit displacement of the work-piece holder on the seat stage.