PURPOSE: A liquid crystal element, having the composition in which a specific croconic methine based compound is dissolved in a liquid crystal, and capable of forming optical images corresponding to optical signals given from He-Ne laser, YAG laser, semiconductor laser or Ar laser.
CONSTITUTION: A liquid crystal element containing a liquid crystal composition of a croconic methine based compound and/or squaric methine based compound expressed by formula I [A- is expressed by formula II or III; X1 and X2 are S, O or Ce; Z1 is (substituted) pyrylium, thiapyrylium, selenapyrylium, etc.; Z2 is (substituted) pyran, thiapyran, selenapyran, etc.; R1WR4 are H, alkyl, alkoxyl, etc.; m and n are 1 or 2] in an amount of preferably 1W3wt% dissolved in the phase A or C of preferably a smectic liquid crystal having positive dielectric anisotropy.
USE: Optical disk systems of the recording method forming a large scope display and pit.
OGUCHI YOSHIHIRO
KANBE JIYUNICHIROU
TAKASU YOSHIO
