Process of producing optical element and optical element

Abstract

A liquid crystal layer is formed on an alignment substrate 13 by the use of a photo-curing chiral nematic liquid crystal having cholesteric regularity, or the like, and liquid crystalline molecules in the liquid crystal layer are aligned by the alignment-regulating action of the alignment substrate 13 . A predetermined amount of radiation 20 is applied to the liquid crystal layer formed on the alignment substrate 13 to three-dimensionally cross-link and cure the liquid crystal layer, thereby forming a cholesteric layer 12 in the semi-cured state. Thereafter, the semi-cured cholesteric layer 12 formed on the alignment substrate 13 is brought into contact with an organic solvent 21 under the specific conditions. There is thus finally obtained an optical element 10 comprising the cholesteric layer 12 formed on the alignment substrate 13.

1 . A process of producing an optical element, comprising: 
 the first step of forming a radiation-curing liquid crystal layer having cholesteric regularity on an alignment substrate having an aligning function;    the second step of applying a predetermined amount of radiation to the liquid crystal layer formed on the alignment substrate to cure the liquid crystal layer, thereby forming a cholesteric layer in the semi-cured state; and    the third step of bringing the semi-cured cholesteric layer formed on the alignment substrate into contact with an organic solvent;    wherein the amount of radiation to be applied to the liquid crystal layer in the second step is changed to control a selective reflection wave range of the cholesteric layer.    
   
   
       2 . The process according to  claim 1 , wherein the radiation is applied, in the second step, in different amounts to different regions on the surface of the liquid crystal layer so that these regions can have different selective reflection wave ranges.  
   
   
       3 . The process according to  claim 1 , wherein the radiation to be applied to the liquid crystal layer in the second step is light selected from the group consisting of ultraviolet light, an electron beam, visible light and infrared light.  
   
   
       4 . The process according to  claim 1 , wherein the liquid crystal layer formed in the first step comprises a chiral nematic liquid crystal obtained by adding a chiral agent to a nematic liquid crystal.  
   
   
       5 . A process of producing an optical element, comprising: 
 the first step of forming a first radiation-curing liquid crystal layer having cholesteric regularity on an alignment substrate having an aligning function;    the second step of applying a predetermined amount of radiation to the first liquid crystal layer formed on the alignment substrate to cure the first liquid crystal layer, thereby forming a first cholesteric film in the semi-cured state;    the third step of bringing the semi-cured first cholesteric film formed on the alignment substrate into contact with an organic solvent;    the fourth step of forming a second radiation-curing liquid crystal layer having cholesteric regularity on the first cholesteric film that has been brought into contact with the organic solvent;    the fifth step of applying a predetermined amount of radiation to the second liquid crystal layer formed on the first cholesteric film to cure the second liquid crystal layer, thereby forming a second cholesteric film in the semi-cured state; and    the sixth step of bringing the semi-cured second cholesteric film formed on the first cholesteric film into contact with an organic solvent;    wherein the amount of radiation to be applied to the first or second liquid crystal layer in the second or fifth step is changed to control a selective reflection wave range of the first or second cholesteric film.    
   
   
       6 . The process according to  claim 5 , wherein the radiation to be applied to the first and second liquid crystal layer in the second and fifth steps is light selected from the group consisting of ultraviolet light, an electron beam, visible light and infrared light.  
   
   
       7 . The process according to  claim 5 , wherein the first and second liquid crystal layers formed in the first and fourth steps comprise a chiral nematic liquid crystal obtained by adding a chiral agent to a nematic liquid crystal.