Electro-optical light modulation element, display and medium

Abstract

The present invention relates to an electro-optical light modulation element and to electro-optical displays and display systems, such as television screens and computer monitors, containing elements of this type. The light modulation elements according to the invention contain a mesogenic modulation medium which is in the isotropic phase during operation of the light modulation elements and are particularly distinguished by very short response times in addition to good contrast and low viewing-angle dependence. The mesogenic modulation media used in the electro-optical light modulation elements are likewise a subject-matter of the present invention.

1 . Electro-optical light modulation element comprising
 an electrode arrangement,   at least one element for polarisation of the light, and   a mesogenic modulation medium, characterised in that the light modulation element   is operated at a temperature at which the mesogenic modulation medium in the unaddressed state is in the isotropic phase.   
   
   
       2 . Light modulation element according to  claim 1 , characterised in that
 the electrode arrangement is able to generate an electric field having a significant component parallel to the surface of the mesogenic modulation medium.   
   
   
       3 . Light modulation element according to at least one of  claims 1  and  2 , characterised in that
 the mesogenic modulation medium has a nematic phase.   
   
   
       4 . Light modulation element according to at least one of  claims 1  to  3 , characterised in that
 the electrode arrangement during operation of the light modulation element generates an electric field having a significant component parallel to the plane of the mesogenic modulation medium.   
   
   
       5 . Light modulation element according to at least one of  claims 1  to  4 , characterised in that
 the light during passage through the light modulation element in each case passes through at least one element for polarisation of the light before passing through the mesogenic modulation medium and after passing through the mesogenic modulation medium.   
   
   
       6 . Light modulation element according to at least one of  claims 1  to  5 , characterised in that
 the electrode arrangement is located on one side of the layer of the mesogenic modulation medium.   
   
   
       7 . Light modulation element according to at least one of  claims 1  to  6 , characterised in that
 it contains an additional birefringent layer.   
   
   
       8 . Electro-optical display containing one or more light modulation elements according to at least one of  claims 1  to  7 . 
   
   
       9 . Electro-optical display according to  claim 8 , characterised in that the display is addressed by means of an active matrix. 
   
   
       10 . Electro-optical display system containing one or more electro-optical displays according to at least one of  claims 8  and  9 . 
   
   
       11 . Electro-optical display system according to  claim 10 , characterised in that it can be used as a television monitor and/or as a computer monitor. 
   
   
       12 . Use of a light modulation element according to at least one of  claims 1  to  6  for the display of information. 
   
   
       13 . Use of an electro-optical display according to at least one of  claims 8  and  9  in an electro-optical display system. 
   
   
       14 . Use of an electro-optical display system according to at least one of  claims 10  and  11  for the display of video signals. 
   
   
       15 . Mesogenic modulation medium, characterised in that it comprises at least one compound of the formula I as described in the text. 
   
   
       16 . Mesogenic modulation medium according to  claim 15  for use in a light modulation element according to at least one of  claims 1  to  6 . 
   
   
       17 . Use of a mesogenic modulation medium according to  claim 15  in an electro-optical light modulation element.