Multifocal polarized sunglasses and lenses

Abstract

Polarized sunglasses and lenses, and methods related thereto, are provided that include multifocal segments and which have a total thickness of less than about 5 millimeters.

1 . A method of making a sunglasses lens, comprising: 
 providing an outer lens layer including a bifocal segment; and    combining the outer lens layer with a polarizing layer and an inner lens layer, wherein the combined thickness of the outer lens layer, the inner lens layer, and the polarizing layer is less than 5 millimeters without grinding of any of the layers.    
   
   
       2 . The method of  claim 1 , wherein the inner lens layer and the polarizing layer are combined before combining with the outer lens layer.  
   
   
       3 . The method of  claim 1 , wherein the combined thickness of the outer lens layer, the inner lens layer, and the polarizing layer is less than about 3 millimeters without grinding of any of the layers.  
   
   
       4 . The method of  claim 1 , wherein the sunglasses lens is for use by a wearer having an eye with a lower limbus, the lower limbus having a center at a vertical level, and wherein the bifocal segment has a bifocal top, and further comprising positioning the bifocal segment within the outer lens layer such that, when in use in the sunglasses frame, the bifocal top is at least about 1 millimeter below the vertical level of the center of the lower limbus.  
   
   
       5 . The method of  claim 4 , wherein positioning comprises positioning the bifocal segment within the outer lens layer such that, when in use in the sunglasses frame, the bifocal top is at least about 5 millimeter below the vertical level of the center of the lower limbus.  
   
   
       6 . The method of  claim 4 , wherein the bifocal top of the bifocal segment is a flat top.  
   
   
       7 . The method of  claim 4 , wherein the bifocal top of the bifocal segment is progressive.  
   
   
       8 . The method of  claim 1 , and further comprising forming the bifocal segment as part of the outer lens layer.  
   
   
       9 . The method of  claim 1 , and further comprising attaching the bifocal segment to the outer lens layer.  
   
   
       10 . A process for making sunglasses, comprising: 
 providing a pair of polarized lenses, wherein each of the polarized lenses includes a bifocal segment, and wherein each of the polarized lenses has a thickness of less than 5 millimeters without grinding;    providing a sunglasses frame; and    coupling the polarized lenses to the sunglasses frame.    
   
   
       11 . The process of  claim 10 , wherein each of the polarized lenses has a thickness of less than about 3 millimeters without grinding.  
   
   
       12 . The process of  claim 10 , wherein providing the pair of polarized lenses comprises, for each of the polarized lenses, combining an outer lens layer with an inner lens layer and a polarizing layer to form the polarized lens, wherein the combined thickness of the outer lens layer, the inner lens layer, and the polarizing layer is less than 5 millimeters without grinding of any of the layers.  
   
   
       13 . The process of  claim 12 , and further comprising forming the bifocal segment as part of the outer lens layer.  
   
   
       14 . The process of  claim 12 , and further comprising forming the bifocal segment as part of the inner lens layer.  
   
   
       15 . The process of  claim 12 , and further comprising attaching the bifocal segment to the outer lens layer.  
   
   
       16 . The process of  claim 12 , and further comprising attaching the bifocal segment to the inner lens layer.  
   
   
       17 . The process of  claim 12 , wherein the sunglasses are for use by a wearer having an eye with a lower limbus, the lower limbus having a center at a vertical level, and wherein each bifocal segment has a bifocal top, and wherein the process further comprises, for each of the polarized lenses, positioning the bifocal segment such that, when in use in the sunglasses frame, the bifocal top is at least about 1 millimeter below the vertical level of the center of the lower limbus.  
   
   
       18 . The process of  claim 17 , wherein positioning comprises positioning the bifocal segment such that, when in use in the sunglasses frame, the bifocal top is at least about 5 millimeters below the vertical level of the center of the lower limbus.