Optical element and optical equipment incorporating the same

Abstract

In order to provide an optical element which prevents fogging of a surface and has an antireflection characteristic and morphological stability, an optical element of the present invention includes: a substrate; and a first water absorption layer containing a water-absorbing polymer and inorganic particles, a high refractive layer, and a second water absorption layer which are formed on a substrate in this order, in which the water absorption layer is made of a material containing a mixture of a water-absorbing polymer and an inorganic substance.

1 . An optical element having an antifog characteristic, comprising: 
 an optical component; and    a first water absorption layer containing a water-absorbing polymer, which is formed on the optical component,    wherein the first water absorption layer contains a mixture of a water-absorbing polymer and an inorganic substance, and    wherein the inorganic substance is inorganic particles, which are mixed in the first water absorption layer in particulate form.    
   
   
       2 . The optical element according to  claim 1 , wherein a rate of the inorganic substance mixed in the first water absorption layer is 5 to 60 w %.  
   
   
       3 . The optical element according to  claim 1 , wherein a rate of the inorganic substance mixed in the first water absorption layer is 15 to 50 w %.  
   
   
       4 . The optical element according to  claim 1 , wherein the inorganic substance is SiO 2 .  
   
   
       5 . The optical element according to  claim 1 , wherein the inorganic particles are contained in the first water absorption layer as particles having a diameter of 5 nm to 20 nm.  
   
   
       6 . The optical element according to  claim 1 , wherein a thickness of the first water absorption layer is 1 μm to 20 μm.  
   
   
       7 . The optical element according to  claim 1 , wherein the optical element is one selected from the group consisting of a filter for a photographic lens or a projection lens, a mirror, and a lens.  
   
   
       8 . The optical element according to  claim 1 , further having an antireflection characteristic.  
   
   
       9 . An optical equipment comprising an optical element as set forth in  claim 1 .  
   
   
       10 . The optical equipment according to  claim 9 , wherein the optical element is exposed to the outside.  
   
   
       11 . The optical equipment according to  claim 9 , wherein the optical equipment is an image pickup apparatus including an image pickup optical system and a finder optical system, the finder optical system including the optical element.  
   
   
       12 . The optical equipment according to  claim 11 , wherein the optical element is an eyepiece of the finder optical system.