Processing apparatus and optical member manufacturing method

Abstract

There is provided a processing apparatus and an optical member manufacturing method that can improve the figure accuracy and the waviness accuracy, and can highly and precisely process an optical element surface. A processing apparatus generates a pressure between a polishing member and a workpiece and relatively moves the polishing member and the workpiece to process a workpiece. The processing apparatus includes a support member that can perform oscillating movement, and a processing portion that is rotatably attached to the support member. The processing portion includes one or more pressure generation units to generate different pressures between the polishing member and the workpiece.

1 . A processing apparatus that generates a pressure between a polishing member and a workpiece and relatively moves the polishing member and the workpiece to process a workpiece, the processing apparatus comprising:
 a support member that can perform oscillating movement; and   a processing portion that is rotatably attached to the support member,   wherein the processing portion includes a plurality of pressure generation units to generate different pressures between the polishing member and the workpiece.   
     
     
         2 . The processing apparatus according to  claim 1 , wherein
 the processing portion is attached to the support member through a frame,   a supporting member is attached to a surface of the frame opposite the workpiece, and   the frame is placed to generate a pressure between the supporting member and the workpiece.   
     
     
         3 . The processing apparatus according to  claim 1 , wherein a plurality of polishing members are provided for each of the pressure generation units. 
     
     
         4 . The processing apparatus according to  claim 1 , wherein the supporting member is provided to surround the polishing member. 
     
     
         5 . The processing apparatus according to  claim 1 , wherein the supporting member is provided between the polishing members. 
     
     
         6 . The processing apparatus according to  claim 1 , wherein a tool unit is formed for each of the pressure generation units and the tool unit includes a central processing unit (CPU) to control the pressure generation unit. 
     
     
         7 . An optical member manufacturing method that generates a pressure between a polishing member and a workpiece and relatively moves the polishing member and the workpiece to process a workpiece, wherein a plurality of pressure generation units is provided to generate different pressures between the polishing member and the workpiece, the method comprising:
 determining a targeted removal quantity at each position on the workpiece from a workpiece shape before processing acquired by measuring the workpiece and a shape of the targeted workpiece, and   processing the workpiece by varying a pressure generated between the polishing member and the workpiece according to a targeted removal quantity at each position on the workpiece.   
     
     
         8 . The optical member manufacturing method according to  claim 7 , wherein a pressure generated from the pressure generation unit is determined by generating a reference pressure from each of the pressure generation units, determining a reference removal quantity at each position on the workpiece during processing for a specified time, determining a pressure correction coefficient at each position on the workpiece from a targeted removal quantity for the workpiece and a reference removal quantity for the workpiece, and correcting a pressure from the pressure generation unit to multiply the reference pressure by the pressure correction coefficient when the pressure generation unit is positioned at each position on the workpiece. 
     
     
         9 . The optical member manufacturing method according to  claim 7 , wherein
 a supporting member is provided around the polishing member, and   a pressure generated between the supporting member and the workpiece compensates a moment occurring according to a change in a pressure generated between the polishing member and the workpiece.