Liquid crystal display device in which the heights of the reflection plate projections are less than half the thicknesses of the two aligning films together

Claim 1

A liquid crystal display device which uses a phase transition type guest-host mode, the device comprising: a pair of substrates with at least one substrate being a transparent substrate and having in the following order a transparent electrode and a first aligning film formed thereon, the other substrate located opposite to the transparent substrate with a liquid crystal composition disposed therebetween, said other substrate having in the following order an insulating film, a reflection plate, and a second aligning film formed thereon; the reflection plate having projections at the surface thereof which is formed through the intermediary of the insulating film having projections at the surface thereof on the substrate; the aligning films being subjected to a vertical aligning treatment relative to the respective substrates; and the liquid crystal composition comprising a nematic liquid crystal, a chiral additive and a two-tone pigment; wherein a helical pitch (P o ) of the liquid crystal composition and the cell thickness (d) of the liquid crystal display device satisfy the relation of 1.5<d/P o <4; wherein a height (d 1 ) of a projection of the reflection plate and a depth (d s ) of the surface layer formed by adding the thickness of the two aligning films on the pair of the substrates subjected to the aligning treatment satisfy the condition of d 1 <d s /2.