Liquid crystal display device with phase element

A liquid crystal display device comprising:

• a liquid crystal display element including a pair of substrates, a liquid crystal layer interposed between the pair of substrates, and an alignment film formed on a surface of at least one of the pair of substrates facing the liquid crystal layer;
• a pair of polarizers disposed on both surfaces of the liquid crystal element to sandwich the liquid crystal element;
• and
• at least one optical phase element disposed between at least one of the pair of polarizers and the liquid crystal element,
• wherein three principal refractive indices na, nb, and nc of an index ellipsoid of the optical phase element have the relationship of na=nc>nb, a direction of the principal refractive index nb is tilted clockwise or counterclockwise from the normal of a surface of the optical phase element with respect to a direction of one of the principal refractive indices na and nc which is substantially parallel to the surface of the optical phase element as an axis, and a direction of the other principal refractive index nc or na is tilted clockwise or counterclockwise from a direction substantially parallel to the surface of the optical phase element, and
• conditions of the combination of a length of a mean alkyl chain of a liquid crystal material of the liquid crystal layer, a rate of variation of an ordinary refractive index no of the liquid crystal material with respect to a wavelength, and a rate of variation of an extraordinary refractive index ne of the liquid crystal material with respect to a wavelength are set in a range in which viewing angle dependent coloring does not occur on a screen, and
• wherein the length m of the mean alkyl chain (CmH2m+1—) of the liquid crystal material is set in a range of m<3.40, and the rate of variation among extraordinary light refractive indices ne(450), ne(550), and ne(650) for light with wavelengths of 450 nm, 550 nm, and 650 nm, respectively, and the rate of variation among ordinary light refractive indices no(450), no(550), and no(650) for light with wavelengths of 450 nm, 550 nm, and;
• 650 nm, respectively, are set in a range of:
• 1.00≦((no(450)-no(550))/(no(550)-no(650)))/((ne(450)-ne(550))/(ne(550)-ne(650)))≦−0.422 m+2.55.

A liquid crystal display device comprising:

• a liquid crystal display element including a pair of substrates, a liquid crystal layer interposed between the pair of substrates, and an alignment film formed on a surface of at least one of the pair of substrates facing the liquid crystal layer;
• a pair of polarizers disposed on both surfaces of the liquid crystal element to sandwich the liquid crystal element;
• and
• at least one optical phase element disposed between at least one of the pair of polarizers and the liquid crystal element,
• wherein three principal refractive indices na, nb, and nc of an index ellipsoid of the optical phase element have the relationship of na=nc>nb, a direction of the principal refractive index nb is tilted clockwise or counterclockwise from the normal of a surface of the optical phase element with respect to a direction of one of the principal refractive indices na and nc which is substantially parallel to the surface of the optical phase element as an axis, and a direction of the other principal refractive index nc or na is tilted clockwise or counterclockwise from a direction substantially parallel to the surface of the optical phase element, and
• conditions of the combination of a length of a mean alkyl chain of a liquid crystal material of the liquid crystal layer, a rate of variation of an ordinary refractive index no of the liquid crystal material with respect to a wavelength, and a rate of variation of an extraordinary refractive index ne of the liquid crystal material with respect to a wavelength are set in a range in which viewing angle dependent coloring does not occur on a screen, and
• wherein the length m of the mean alkyl chain (CmH2m+1—) of the liquid crystal material is set in a range of 3.40≦m≦3.90, and the rate of variation among extraordinary light refractive indices ne(450), ne(550), and ne(650) for light with wavelengths of 450 nm, 550 nm, and 650 nm, respectively, and the rate of variation among ordinary light refractive indices no(450), no(550), and no(650) for light with wavelengths of 450 nm, 550 nm, and 650 nm, respectively, are set in a range of:
• 0.80≦((no(450)-no(550))/(no(550)-no(650)))/((ne(450)-ne(550))/(ne(550)-ne(650)))≦1.20.

A liquid crystal display device comprising:

• a liquid crystal display element including a pair of substrates, a liquid crystal layer interposed between the pair of substrates, and an alignment film formed on a surface of at least one of the pair of substrates facing the liquid crystal layer;
• a pair of polarizers disposed on both surfaces of the liquid crystal element to sandwich the liquid crystal element;
• and
• at least one optical phase element disposed between at least one of the pair of polarizers and the liquid crystal element,
• wherein three principal refractive indices na, nb, and nc of an index ellipsoid of the optical phase element have the relationship of na=nc>nb, a direction of the principal refractive index nb is tilted clockwise or counterclockwise from the normal of a surface of the optical phase element with respect to a direction of one of the principal refractive indices na and nc which is substantially parallel to the surface of the optical phase element as an axis, and a direction of the other principal refractive index nc or na is tilted clockwise or counterclockwise from a direction substantially parallel to the surface of the optical phase element, and
• conditions of the combination of a length of a mean alkyl chain of a liquid crystal material of the liquid crystal layer, a rate of variation of an ordinary refractive index no of the liquid crystal material with respect to a wavelength, and a rate of variation of an extraordinary refractive index ne of the liquid crystal material with respect to a wavelength are set in a range in which viewing angle dependent coloring does not occur on a screen, and
• wherein the length m of the mean alkyl chain (CmH2m+1—) of the liquid crystal material is set in a range of m>3.90, and the rate of variation among extraordinary light refractive indices ne(450), ne(550), and ne(650) for light with wavelengths of 450 nm, 550 nm, :
• and 650 nm, respectively, and the rate of variation among ordinary light refractive indices no(450), no(550), and no(650) for light with wavelengths of 450 nm, 550 nm, and 650 nm, respectively, are set in a range of:
• −0.422 m+2.55((no(450)-no(550))/(no(550)-
• no(650)))/((ne(450)-ne(550))/(ne(550)-ne(650)))≦1.00.