A double-sided polishing method for an optical lens belongs to the technical field of ultra-precision machining. In the double-sided polishing method, upper and lower surfaces of the lens are polished simultaneously by arranging abrasive tools on upper and lower positions of the lens, making the abrasive tools close to the upper and lower surfaces of the lens to swing back and forth in the polishing process, producing relative motion and removing the surface materials. In the present invention, in order to eliminate a problem of removal ununiformity, a method for swing machining of abrasive tools and methods for turning over and polishing of workpieces are adopted in a polishing process, which can realize the high efficiency double-sided high-precision machining for a nonplanar lens, and the method can be applied to the double-sided polishing for different types of lenses.

A double-sided polishing method for an optical lens belongs to the technical field of ultra-precision machining. In the double-sided polishing method, upper and lower surfaces of the lens are polished simultaneously by arranging abrasive tools on upper and lower positions of the lens, making the abrasive tools close to the upper and lower surfaces of the lens to swing back and forth in the polishing process, producing relative motion and removing the surface materials. In the present invention, in order to eliminate a problem of removal ununiformity, a method for swing machining of abrasive tools and methods for turning over and polishing of workpieces are adopted in a polishing process, which can realize the high efficiency double-sided high-precision machining for a nonplanar lens, and the method can be applied to the double-sided polishing for different types of lenses.

A workpiece processing apparatus including a control unit that is provided with a storage medium on which a polishing load measured when an upper turn table is moved downward to a fixed position in a state wherein the workpiece is properly held in holding hole of the carrier is recorded in advance, calculates a difference between a polishing load measured when upper turn table is moved downward to the fixed position in a state wherein the workpiece is held in holding hole of the carrier and the polishing load recorded on the storage medium, and judges the occurrence of abnormal holding of the workpiece if the calculated difference exceeds a threshold value. As a result, it becomes possible to detect abnormal holding of a workpiece in a short time with a high degree of precision before the workpiece is processed and prevent breakages of the workpiece and the processing apparatus.

A workpiece processing apparatus including a control unit that is provided with a storage medium on which a polishing load measured when an upper turn table is moved downward to a fixed position in a state wherein the workpiece is properly held in holding hole of the carrier is recorded in advance, calculates a difference between a polishing load measured when upper turn table is moved downward to the fixed position in a state wherein the workpiece is held in holding hole of the carrier and the polishing load recorded on the storage medium, and judges the occurrence of abnormal holding of the workpiece if the calculated difference exceeds a threshold value. As a result, it becomes possible to detect abnormal holding of a workpiece in a short time with a high degree of precision before the workpiece is processed and prevent breakages of the workpiece and the processing apparatus.

A method for processing a wafer including; surface-grinding front surface of the wafer and back surface opposite to the front surface with a grindstone having a size of 10000 or more and, double-side polishing both sides of the wafer that has been surface-ground so that removal on the back surface is ? or less than that on the front surface. This method can also process a wafer capable of selectively roughening the back surface of a wafer and suppressing warpage of the wafer due to stress, and a wafer having a sufficiently roughened back surface and having a small warpage.

A method for processing a wafer including; surface-grinding front surface of the wafer and back surface opposite to the front surface with a grindstone having a size of 10000 or more and, double-side polishing both sides of the wafer that has been surface-ground so that removal on the back surface is ? or less than that on the front surface. This method can also process a wafer capable of selectively roughening the back surface of a wafer and suppressing warpage of the wafer due to stress, and a wafer having a sufficiently roughened back surface and having a small warpage.

The present invention provides an optical member including an organic polymer. This optical member includes a surface A which has an area of 1 mm.sup.2 or more, and in which the flatness of a region having an area of 1 mm.sup.2, as measured by a non-contact type optical flatness meter, is 80 ?m or less.

The present invention provides an optical member including an organic polymer. This optical member includes a surface A which has an area of 1 mm.sup.2 or more, and in which the flatness of a region having an area of 1 mm.sup.2, as measured by a non-contact type optical flatness meter, is 80 ?m or less.

A method for producing a glass article is provided. The method for producing a glass article, the method including preparing a glass to be processed, the glass comprising a glass bulk and a low-refractive surface layer disposed on the glass bulk, and etching away the low-refractive surface layer to form an etched glass, wherein the etching away the low-refractive surface layer comprises: cleaning the low-refractive surface layer with an acid solution; and cleaning the low-refractive surface layer with a base solution after the cleaning it with the acid solution.

An inner-periphery-side cutoff part where a polishing surface of an upper plate inclines upward toward an inner periphery part of the upper plate and an inner-periphery-side cutoff part where a polishing surface of a lower plate inclines downward toward an inner periphery part of the lower plate are respectively formed on the respective inner periphery parts of the upper plate and the lower plate, or an outer-periphery-side cutoff part where the polishing surface of the upper plate inclines upward toward an outer periphery part of the upper plate and an outer-periphery-side cutoff part where the polishing surface of the lower plate inclines downward toward an outer periphery part of the lower plate are respectively formed on the respective outer periphery parts of the upper plate and the lower plate, or all of them are formed thereon.